gdb

[deliverable/binutils-gdb.git] / gdb / dwarf2read.c

/* DWARF 2 debugging format support for GDB.

   Copyright (C) 1994, 1995, 1996, 1997, 1998, 1999, 2000, 2001, 2002, 2003,
                 2004, 2005, 2006, 2007, 2008, 2009, 2010
                 Free Software Foundation, Inc.

   Adapted by Gary Funck (gary@intrepid.com), Intrepid Technology,
   Inc.  with support from Florida State University (under contract
   with the Ada Joint Program Office), and Silicon Graphics, Inc.
   Initial contribution by Brent Benson, Harris Computer Systems, Inc.,
   based on Fred Fish's (Cygnus Support) implementation of DWARF 1
   support.

   This file is part of GDB.

   This program is free software; you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
   the Free Software Foundation; either version 3 of the License, or
   (at your option) any later version.

   This program is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   GNU General Public License for more details.

   You should have received a copy of the GNU General Public License
   along with this program.  If not, see <http://www.gnu.org/licenses/>.  */

#include "defs.h"
#include "bfd.h"
#include "symtab.h"
#include "gdbtypes.h"
#include "objfiles.h"
#include "dwarf2.h"
#include "buildsym.h"
#include "demangle.h"
#include "expression.h"
#include "filenames.h"  /* for DOSish file names */
#include "macrotab.h"
#include "language.h"
#include "complaints.h"
#include "bcache.h"
#include "dwarf2expr.h"
#include "dwarf2loc.h"
#include "cp-support.h"
#include "hashtab.h"
#include "command.h"
#include "gdbcmd.h"
#include "block.h"
#include "addrmap.h"
#include "typeprint.h"
#include "jv-lang.h"
#include "psympriv.h"
#include "exceptions.h"
#include "gdb_stat.h"

#include <fcntl.h>
#include "gdb_string.h"
#include "gdb_assert.h"
#include <sys/types.h>
#ifdef HAVE_ZLIB_H
#include <zlib.h>
#endif
#ifdef HAVE_MMAP
#include <sys/mman.h>
#ifndef MAP_FAILED
#define MAP_FAILED ((void *) -1)
#endif
#endif

#if 0
/* .debug_info header for a compilation unit
   Because of alignment constraints, this structure has padding and cannot
   be mapped directly onto the beginning of the .debug_info section.  */
typedef struct comp_unit_header
  {
    unsigned int length;        /* length of the .debug_info
                                   contribution */
    unsigned short version;     /* version number -- 2 for DWARF
                                   version 2 */
    unsigned int abbrev_offset; /* offset into .debug_abbrev section */
    unsigned char addr_size;    /* byte size of an address -- 4 */
  }
_COMP_UNIT_HEADER;
#define _ACTUAL_COMP_UNIT_HEADER_SIZE 11
#endif

/* .debug_line statement program prologue
   Because of alignment constraints, this structure has padding and cannot
   be mapped directly onto the beginning of the .debug_info section.  */
typedef struct statement_prologue
  {
    unsigned int total_length;  /* byte length of the statement
                                   information */
    unsigned short version;     /* version number -- 2 for DWARF
                                   version 2 */
    unsigned int prologue_length;       /* # bytes between prologue &
                                           stmt program */
    unsigned char minimum_instruction_length;   /* byte size of
                                                   smallest instr */
    unsigned char default_is_stmt;      /* initial value of is_stmt
                                           register */
    char line_base;
    unsigned char line_range;
    unsigned char opcode_base;  /* number assigned to first special
                                   opcode */
    unsigned char *standard_opcode_lengths;
  }
_STATEMENT_PROLOGUE;

/* When non-zero, dump DIEs after they are read in.  */
static int dwarf2_die_debug = 0;

static int pagesize;

/* When set, the file that we're processing is known to have debugging
   info for C++ namespaces.  GCC 3.3.x did not produce this information,
   but later versions do.  */

static int processing_has_namespace_info;

static const struct objfile_data *dwarf2_objfile_data_key;

struct dwarf2_section_info
{
  asection *asection;
  gdb_byte *buffer;
  bfd_size_type size;
  int was_mmapped;
  /* True if we have tried to read this section.  */
  int readin;
};

/* All offsets in the index are of this type.  It must be
   architecture-independent.  */
typedef uint32_t offset_type;

DEF_VEC_I (offset_type);

/* A description of the mapped index.  The file format is described in
   a comment by the code that writes the index.  */
struct mapped_index
{
  /* The total length of the buffer.  */
  off_t total_size;
  /* A pointer to the address table data.  */
  const gdb_byte *address_table;
  /* Size of the address table data in bytes.  */
  offset_type address_table_size;
  /* The hash table.  */
  const offset_type *index_table;
  /* Size in slots, each slot is 2 offset_types.  */
  offset_type index_table_slots;
  /* A pointer to the constant pool.  */
  const char *constant_pool;
};

typedef struct dwarf2_per_cu_data *dwarf2_per_cu_data_ptr;
DEF_VEC_P (dwarf2_per_cu_data_ptr);

struct dwarf2_per_objfile
{
  struct dwarf2_section_info info;
  struct dwarf2_section_info abbrev;
  struct dwarf2_section_info line;
  struct dwarf2_section_info loc;
  struct dwarf2_section_info macinfo;
  struct dwarf2_section_info str;
  struct dwarf2_section_info ranges;
  struct dwarf2_section_info types;
  struct dwarf2_section_info frame;
  struct dwarf2_section_info eh_frame;
  struct dwarf2_section_info gdb_index;

  /* Back link.  */
  struct objfile *objfile;

  /* A list of all the compilation units.  This is used to locate
     the target compilation unit of a particular reference.  */
  struct dwarf2_per_cu_data **all_comp_units;

  /* The number of compilation units in ALL_COMP_UNITS.  */
  int n_comp_units;

  /* A chain of compilation units that are currently read in, so that
     they can be freed later.  */
  struct dwarf2_per_cu_data *read_in_chain;

  /* A table mapping .debug_types signatures to its signatured_type entry.
     This is NULL if the .debug_types section hasn't been read in yet.  */
  htab_t signatured_types;

  /* A flag indicating wether this objfile has a section loaded at a
     VMA of 0.  */
  int has_section_at_zero;

  /* True if we are using the mapped index.  */
  unsigned char using_index;

  /* The mapped index.  */
  struct mapped_index *index_table;
};

static struct dwarf2_per_objfile *dwarf2_per_objfile;

/* names of the debugging sections */

/* Note that if the debugging section has been compressed, it might
   have a name like .zdebug_info.  */

#define INFO_SECTION     "debug_info"
#define ABBREV_SECTION   "debug_abbrev"
#define LINE_SECTION     "debug_line"
#define LOC_SECTION      "debug_loc"
#define MACINFO_SECTION  "debug_macinfo"
#define STR_SECTION      "debug_str"
#define RANGES_SECTION   "debug_ranges"
#define TYPES_SECTION    "debug_types"
#define FRAME_SECTION    "debug_frame"
#define EH_FRAME_SECTION "eh_frame"
#define GDB_INDEX_SECTION "gdb_index"

/* local data types */

/* We hold several abbreviation tables in memory at the same time. */
#ifndef ABBREV_HASH_SIZE
#define ABBREV_HASH_SIZE 121
#endif

/* The data in a compilation unit header, after target2host
   translation, looks like this.  */
struct comp_unit_head
{
  unsigned int length;
  short version;
  unsigned char addr_size;
  unsigned char signed_addr_p;
  unsigned int abbrev_offset;

  /* Size of file offsets; either 4 or 8.  */
  unsigned int offset_size;

  /* Size of the length field; either 4 or 12.  */
  unsigned int initial_length_size;

  /* Offset to the first byte of this compilation unit header in the
     .debug_info section, for resolving relative reference dies.  */
  unsigned int offset;

  /* Offset to first die in this cu from the start of the cu.
     This will be the first byte following the compilation unit header.  */
  unsigned int first_die_offset;
};

/* Internal state when decoding a particular compilation unit.  */
struct dwarf2_cu
{
  /* The objfile containing this compilation unit.  */
  struct objfile *objfile;

  /* The header of the compilation unit.  */
  struct comp_unit_head header;

  /* Base address of this compilation unit.  */
  CORE_ADDR base_address;

  /* Non-zero if base_address has been set.  */
  int base_known;

  struct function_range *first_fn, *last_fn, *cached_fn;

  /* The language we are debugging.  */
  enum language language;
  const struct language_defn *language_defn;

  const char *producer;

  /* The generic symbol table building routines have separate lists for
     file scope symbols and all all other scopes (local scopes).  So
     we need to select the right one to pass to add_symbol_to_list().
     We do it by keeping a pointer to the correct list in list_in_scope.

     FIXME: The original dwarf code just treated the file scope as the
     first local scope, and all other local scopes as nested local
     scopes, and worked fine.  Check to see if we really need to
     distinguish these in buildsym.c.  */
  struct pending **list_in_scope;

  /* DWARF abbreviation table associated with this compilation unit.  */
  struct abbrev_info **dwarf2_abbrevs;

  /* Storage for the abbrev table.  */
  struct obstack abbrev_obstack;

  /* Hash table holding all the loaded partial DIEs.  */
  htab_t partial_dies;

  /* Storage for things with the same lifetime as this read-in compilation
     unit, including partial DIEs.  */
  struct obstack comp_unit_obstack;

  /* When multiple dwarf2_cu structures are living in memory, this field
     chains them all together, so that they can be released efficiently.
     We will probably also want a generation counter so that most-recently-used
     compilation units are cached...  */
  struct dwarf2_per_cu_data *read_in_chain;

  /* Backchain to our per_cu entry if the tree has been built.  */
  struct dwarf2_per_cu_data *per_cu;

  /* Pointer to the die -> type map.  Although it is stored
     permanently in per_cu, we copy it here to avoid double
     indirection.  */
  htab_t type_hash;

  /* How many compilation units ago was this CU last referenced?  */
  int last_used;

  /* A hash table of die offsets for following references.  */
  htab_t die_hash;

  /* Full DIEs if read in.  */
  struct die_info *dies;

  /* A set of pointers to dwarf2_per_cu_data objects for compilation
     units referenced by this one.  Only set during full symbol processing;
     partial symbol tables do not have dependencies.  */
  htab_t dependencies;

  /* Header data from the line table, during full symbol processing.  */
  struct line_header *line_header;

  /* Mark used when releasing cached dies.  */
  unsigned int mark : 1;

  /* This flag will be set if this compilation unit might include
     inter-compilation-unit references.  */
  unsigned int has_form_ref_addr : 1;

  /* This flag will be set if this compilation unit includes any
     DW_TAG_namespace DIEs.  If we know that there are explicit
     DIEs for namespaces, we don't need to try to infer them
     from mangled names.  */
  unsigned int has_namespace_info : 1;
};

/* When using the index (and thus not using psymtabs), each CU has an
   object of this type.  This is used to hold information needed by
   the various "quick" methods.  */
struct dwarf2_per_cu_quick_data
{
  /* The line table.  This can be NULL if there was no line table.  */
  struct line_header *lines;

  /* The file names from the line table.  */
  const char **file_names;
  /* The file names from the line table after being run through
     gdb_realpath.  */
  const char **full_names;

  /* The corresponding symbol table.  This is NULL if symbols for this
     CU have not yet been read.  */
  struct symtab *symtab;

  /* A temporary mark bit used when iterating over all CUs in
     expand_symtabs_matching.  */
  unsigned int mark : 1;

  /* True if we've tried to read the line table.  */
  unsigned int read_lines : 1;
};

/* Persistent data held for a compilation unit, even when not
   processing it.  We put a pointer to this structure in the
   read_symtab_private field of the psymtab.  If we encounter
   inter-compilation-unit references, we also maintain a sorted
   list of all compilation units.  */

struct dwarf2_per_cu_data
{
  /* The start offset and length of this compilation unit.  2**29-1
     bytes should suffice to store the length of any compilation unit
     - if it doesn't, GDB will fall over anyway.
     NOTE: Unlike comp_unit_head.length, this length includes
     initial_length_size.  */
  unsigned int offset;
  unsigned int length : 29;

  /* Flag indicating this compilation unit will be read in before
     any of the current compilation units are processed.  */
  unsigned int queued : 1;

  /* This flag will be set if we need to load absolutely all DIEs
     for this compilation unit, instead of just the ones we think
     are interesting.  It gets set if we look for a DIE in the
     hash table and don't find it.  */
  unsigned int load_all_dies : 1;

  /* Non-zero if this CU is from .debug_types.
     Otherwise it's from .debug_info.  */
  unsigned int from_debug_types : 1;

  /* Set to non-NULL iff this CU is currently loaded.  When it gets freed out
     of the CU cache it gets reset to NULL again.  */
  struct dwarf2_cu *cu;

  /* If full symbols for this CU have been read in, then this field
     holds a map of DIE offsets to types.  It isn't always possible
     to reconstruct this information later, so we have to preserve
     it.  */
  htab_t type_hash;

  /* The corresponding objfile.  */
  struct objfile *objfile;

  /* When using partial symbol tables, the 'psymtab' field is active.
     Otherwise the 'quick' field is active.  */
  union
  {
    /* The partial symbol table associated with this compilation unit,
       or NULL for partial units (which do not have an associated
       symtab).  */
    struct partial_symtab *psymtab;

    /* Data needed by the "quick" functions.  */
    struct dwarf2_per_cu_quick_data *quick;
  } v;
};

/* Entry in the signatured_types hash table.  */

struct signatured_type
{
  ULONGEST signature;

  /* Offset in .debug_types of the TU (type_unit) for this type.  */
  unsigned int offset;

  /* Offset in .debug_types of the type defined by this TU.  */
  unsigned int type_offset;

  /* The CU(/TU) of this type.  */
  struct dwarf2_per_cu_data per_cu;
};

/* Struct used to pass misc. parameters to read_die_and_children, et. al.
   which are used for both .debug_info and .debug_types dies.
   All parameters here are unchanging for the life of the call.
   This struct exists to abstract away the constant parameters of
   die reading.  */

struct die_reader_specs
{
  /* The bfd of this objfile.  */
  bfd* abfd;

  /* The CU of the DIE we are parsing.  */
  struct dwarf2_cu *cu;

  /* Pointer to start of section buffer.
     This is either the start of .debug_info or .debug_types.  */
  const gdb_byte *buffer;
};

/* The line number information for a compilation unit (found in the
   .debug_line section) begins with a "statement program header",
   which contains the following information.  */
struct line_header
{
  unsigned int total_length;
  unsigned short version;
  unsigned int header_length;
  unsigned char minimum_instruction_length;
  unsigned char maximum_ops_per_instruction;
  unsigned char default_is_stmt;
  int line_base;
  unsigned char line_range;
  unsigned char opcode_base;

  /* standard_opcode_lengths[i] is the number of operands for the
     standard opcode whose value is i.  This means that
     standard_opcode_lengths[0] is unused, and the last meaningful
     element is standard_opcode_lengths[opcode_base - 1].  */
  unsigned char *standard_opcode_lengths;

  /* The include_directories table.  NOTE!  These strings are not
     allocated with xmalloc; instead, they are pointers into
     debug_line_buffer.  If you try to free them, `free' will get
     indigestion.  */
  unsigned int num_include_dirs, include_dirs_size;
  char **include_dirs;

  /* The file_names table.  NOTE!  These strings are not allocated
     with xmalloc; instead, they are pointers into debug_line_buffer.
     Don't try to free them directly.  */
  unsigned int num_file_names, file_names_size;
  struct file_entry
  {
    char *name;
    unsigned int dir_index;
    unsigned int mod_time;
    unsigned int length;
    int included_p; /* Non-zero if referenced by the Line Number Program.  */
    struct symtab *symtab; /* The associated symbol table, if any.  */
  } *file_names;

  /* The start and end of the statement program following this
     header.  These point into dwarf2_per_objfile->line_buffer.  */
  gdb_byte *statement_program_start, *statement_program_end;
};

/* When we construct a partial symbol table entry we only
   need this much information. */
struct partial_die_info
  {
    /* Offset of this DIE.  */
    unsigned int offset;

    /* DWARF-2 tag for this DIE.  */
    ENUM_BITFIELD(dwarf_tag) tag : 16;

    /* Assorted flags describing the data found in this DIE.  */
    unsigned int has_children : 1;
    unsigned int is_external : 1;
    unsigned int is_declaration : 1;
    unsigned int has_type : 1;
    unsigned int has_specification : 1;
    unsigned int has_pc_info : 1;

    /* Flag set if the SCOPE field of this structure has been
       computed.  */
    unsigned int scope_set : 1;

    /* Flag set if the DIE has a byte_size attribute.  */
    unsigned int has_byte_size : 1;

    /* The name of this DIE.  Normally the value of DW_AT_name, but
       sometimes a default name for unnamed DIEs.  */
    char *name;

    /* The scope to prepend to our children.  This is generally
       allocated on the comp_unit_obstack, so will disappear
       when this compilation unit leaves the cache.  */
    char *scope;

    /* The location description associated with this DIE, if any.  */
    struct dwarf_block *locdesc;

    /* If HAS_PC_INFO, the PC range associated with this DIE.  */
    CORE_ADDR lowpc;
    CORE_ADDR highpc;

    /* Pointer into the info_buffer (or types_buffer) pointing at the target of
       DW_AT_sibling, if any.  */
    gdb_byte *sibling;

    /* If HAS_SPECIFICATION, the offset of the DIE referred to by
       DW_AT_specification (or DW_AT_abstract_origin or
       DW_AT_extension).  */
    unsigned int spec_offset;

    /* Pointers to this DIE's parent, first child, and next sibling,
       if any.  */
    struct partial_die_info *die_parent, *die_child, *die_sibling;
  };

/* This data structure holds the information of an abbrev. */
struct abbrev_info
  {
    unsigned int number;        /* number identifying abbrev */
    enum dwarf_tag tag;         /* dwarf tag */
    unsigned short has_children;                /* boolean */
    unsigned short num_attrs;   /* number of attributes */
    struct attr_abbrev *attrs;  /* an array of attribute descriptions */
    struct abbrev_info *next;   /* next in chain */
  };

struct attr_abbrev
  {
    ENUM_BITFIELD(dwarf_attribute) name : 16;
    ENUM_BITFIELD(dwarf_form) form : 16;
  };

/* Attributes have a name and a value */
struct attribute
  {
    ENUM_BITFIELD(dwarf_attribute) name : 16;
    ENUM_BITFIELD(dwarf_form) form : 15;

    /* Has DW_STRING already been updated by dwarf2_canonicalize_name?  This
       field should be in u.str (existing only for DW_STRING) but it is kept
       here for better struct attribute alignment.  */
    unsigned int string_is_canonical : 1;

    union
      {
        char *str;
        struct dwarf_block *blk;
        ULONGEST unsnd;
        LONGEST snd;
        CORE_ADDR addr;
        struct signatured_type *signatured_type;
      }
    u;
  };

/* This data structure holds a complete die structure. */
struct die_info
  {
    /* DWARF-2 tag for this DIE.  */
    ENUM_BITFIELD(dwarf_tag) tag : 16;

    /* Number of attributes */
    unsigned short num_attrs;

    /* Abbrev number */
    unsigned int abbrev;

    /* Offset in .debug_info or .debug_types section.  */
    unsigned int offset;

    /* The dies in a compilation unit form an n-ary tree.  PARENT
       points to this die's parent; CHILD points to the first child of
       this node; and all the children of a given node are chained
       together via their SIBLING fields, terminated by a die whose
       tag is zero.  */
    struct die_info *child;     /* Its first child, if any.  */
    struct die_info *sibling;   /* Its next sibling, if any.  */
    struct die_info *parent;    /* Its parent, if any.  */

    /* An array of attributes, with NUM_ATTRS elements.  There may be
       zero, but it's not common and zero-sized arrays are not
       sufficiently portable C.  */
    struct attribute attrs[1];
  };

struct function_range
{
  const char *name;
  CORE_ADDR lowpc, highpc;
  int seen_line;
  struct function_range *next;
};

/* Get at parts of an attribute structure */

#define DW_STRING(attr)    ((attr)->u.str)
#define DW_STRING_IS_CANONICAL(attr) ((attr)->string_is_canonical)
#define DW_UNSND(attr)     ((attr)->u.unsnd)
#define DW_BLOCK(attr)     ((attr)->u.blk)
#define DW_SND(attr)       ((attr)->u.snd)
#define DW_ADDR(attr)      ((attr)->u.addr)
#define DW_SIGNATURED_TYPE(attr) ((attr)->u.signatured_type)

/* Blocks are a bunch of untyped bytes. */
struct dwarf_block
  {
    unsigned int size;
    gdb_byte *data;
  };

#ifndef ATTR_ALLOC_CHUNK
#define ATTR_ALLOC_CHUNK 4
#endif

/* Allocate fields for structs, unions and enums in this size.  */
#ifndef DW_FIELD_ALLOC_CHUNK
#define DW_FIELD_ALLOC_CHUNK 4
#endif

/* FIXME: We might want to set this from BFD via bfd_arch_bits_per_byte,
   but this would require a corresponding change in unpack_field_as_long
   and friends.  */
static int bits_per_byte = 8;

/* The routines that read and process dies for a C struct or C++ class
   pass lists of data member fields and lists of member function fields
   in an instance of a field_info structure, as defined below.  */
struct field_info
  {
    /* List of data member and baseclasses fields. */
    struct nextfield
      {
        struct nextfield *next;
        int accessibility;
        int virtuality;
        struct field field;
      }
     *fields, *baseclasses;

    /* Number of fields (including baseclasses).  */
    int nfields;

    /* Number of baseclasses.  */
    int nbaseclasses;

    /* Set if the accesibility of one of the fields is not public.  */
    int non_public_fields;

    /* Member function fields array, entries are allocated in the order they
       are encountered in the object file.  */
    struct nextfnfield
      {
        struct nextfnfield *next;
        struct fn_field fnfield;
      }
     *fnfields;

    /* Member function fieldlist array, contains name of possibly overloaded
       member function, number of overloaded member functions and a pointer
       to the head of the member function field chain.  */
    struct fnfieldlist
      {
        char *name;
        int length;
        struct nextfnfield *head;
      }
     *fnfieldlists;

    /* Number of entries in the fnfieldlists array.  */
    int nfnfields;

    /* typedefs defined inside this class.  TYPEDEF_FIELD_LIST contains head of
       a NULL terminated list of TYPEDEF_FIELD_LIST_COUNT elements.  */
    struct typedef_field_list
      {
        struct typedef_field field;
        struct typedef_field_list *next;
      }
    *typedef_field_list;
    unsigned typedef_field_list_count;
  };

/* One item on the queue of compilation units to read in full symbols
   for.  */
struct dwarf2_queue_item
{
  struct dwarf2_per_cu_data *per_cu;
  struct dwarf2_queue_item *next;
};

/* The current queue.  */
static struct dwarf2_queue_item *dwarf2_queue, *dwarf2_queue_tail;

/* Loaded secondary compilation units are kept in memory until they
   have not been referenced for the processing of this many
   compilation units.  Set this to zero to disable caching.  Cache
   sizes of up to at least twenty will improve startup time for
   typical inter-CU-reference binaries, at an obvious memory cost.  */
static int dwarf2_max_cache_age = 5;
static void
show_dwarf2_max_cache_age (struct ui_file *file, int from_tty,
                           struct cmd_list_element *c, const char *value)
{
  fprintf_filtered (file, _("\
The upper bound on the age of cached dwarf2 compilation units is %s.\n"),
                    value);
}


/* Various complaints about symbol reading that don't abort the process */

static void
dwarf2_statement_list_fits_in_line_number_section_complaint (void)
{
  complaint (&symfile_complaints,
             _("statement list doesn't fit in .debug_line section"));
}

static void
dwarf2_debug_line_missing_file_complaint (void)
{
  complaint (&symfile_complaints,
             _(".debug_line section has line data without a file"));
}

static void
dwarf2_debug_line_missing_end_sequence_complaint (void)
{
  complaint (&symfile_complaints,
             _(".debug_line section has line program sequence without an end"));
}

static void
dwarf2_complex_location_expr_complaint (void)
{
  complaint (&symfile_complaints, _("location expression too complex"));
}

static void
dwarf2_const_value_length_mismatch_complaint (const char *arg1, int arg2,
                                              int arg3)
{
  complaint (&symfile_complaints,
             _("const value length mismatch for '%s', got %d, expected %d"), arg1,
             arg2, arg3);
}

static void
dwarf2_macros_too_long_complaint (void)
{
  complaint (&symfile_complaints,
             _("macro info runs off end of `.debug_macinfo' section"));
}

static void
dwarf2_macro_malformed_definition_complaint (const char *arg1)
{
  complaint (&symfile_complaints,
             _("macro debug info contains a malformed macro definition:\n`%s'"),
             arg1);
}

static void
dwarf2_invalid_attrib_class_complaint (const char *arg1, const char *arg2)
{
  complaint (&symfile_complaints,
             _("invalid attribute class or form for '%s' in '%s'"), arg1, arg2);
}

/* local function prototypes */

static void dwarf2_locate_sections (bfd *, asection *, void *);

static void dwarf2_create_include_psymtab (char *, struct partial_symtab *,
                                           struct objfile *);

static void dwarf2_build_include_psymtabs (struct dwarf2_cu *,
                                           struct die_info *,
                                           struct partial_symtab *);

static void dwarf2_build_psymtabs_hard (struct objfile *);

static void scan_partial_symbols (struct partial_die_info *,
                                  CORE_ADDR *, CORE_ADDR *,
                                  int, struct dwarf2_cu *);

static void add_partial_symbol (struct partial_die_info *,
                                struct dwarf2_cu *);

static void add_partial_namespace (struct partial_die_info *pdi,
                                   CORE_ADDR *lowpc, CORE_ADDR *highpc,
                                   int need_pc, struct dwarf2_cu *cu);

static void add_partial_module (struct partial_die_info *pdi, CORE_ADDR *lowpc,
                                CORE_ADDR *highpc, int need_pc,
                                struct dwarf2_cu *cu);

static void add_partial_enumeration (struct partial_die_info *enum_pdi,
                                     struct dwarf2_cu *cu);

static void add_partial_subprogram (struct partial_die_info *pdi,
                                    CORE_ADDR *lowpc, CORE_ADDR *highpc,
                                    int need_pc, struct dwarf2_cu *cu);

static gdb_byte *locate_pdi_sibling (struct partial_die_info *orig_pdi,
                                     gdb_byte *buffer, gdb_byte *info_ptr,
                                     bfd *abfd, struct dwarf2_cu *cu);

static void dwarf2_psymtab_to_symtab (struct partial_symtab *);

static void psymtab_to_symtab_1 (struct partial_symtab *);

static void dwarf2_read_abbrevs (bfd *abfd, struct dwarf2_cu *cu);

static void dwarf2_free_abbrev_table (void *);

static struct abbrev_info *peek_die_abbrev (gdb_byte *, unsigned int *,
                                            struct dwarf2_cu *);

static struct abbrev_info *dwarf2_lookup_abbrev (unsigned int,
                                                 struct dwarf2_cu *);

static struct partial_die_info *load_partial_dies (bfd *,
                                                   gdb_byte *, gdb_byte *,
                                                   int, struct dwarf2_cu *);

static gdb_byte *read_partial_die (struct partial_die_info *,
                                   struct abbrev_info *abbrev,
                                   unsigned int, bfd *,
                                   gdb_byte *, gdb_byte *,
                                   struct dwarf2_cu *);

static struct partial_die_info *find_partial_die (unsigned int,
                                                  struct dwarf2_cu *);

static void fixup_partial_die (struct partial_die_info *,
                               struct dwarf2_cu *);

static gdb_byte *read_attribute (struct attribute *, struct attr_abbrev *,
                                 bfd *, gdb_byte *, struct dwarf2_cu *);

static gdb_byte *read_attribute_value (struct attribute *, unsigned,
                                       bfd *, gdb_byte *, struct dwarf2_cu *);

static unsigned int read_1_byte (bfd *, gdb_byte *);

static int read_1_signed_byte (bfd *, gdb_byte *);

static unsigned int read_2_bytes (bfd *, gdb_byte *);

static unsigned int read_4_bytes (bfd *, gdb_byte *);

static ULONGEST read_8_bytes (bfd *, gdb_byte *);

static CORE_ADDR read_address (bfd *, gdb_byte *ptr, struct dwarf2_cu *,
                               unsigned int *);

static LONGEST read_initial_length (bfd *, gdb_byte *, unsigned int *);

static LONGEST read_checked_initial_length_and_offset
  (bfd *, gdb_byte *, const struct comp_unit_head *,
   unsigned int *, unsigned int *);

static LONGEST read_offset (bfd *, gdb_byte *, const struct comp_unit_head *,
                            unsigned int *);

static LONGEST read_offset_1 (bfd *, gdb_byte *, unsigned int);

static gdb_byte *read_n_bytes (bfd *, gdb_byte *, unsigned int);

static char *read_string (bfd *, gdb_byte *, unsigned int *);

static char *read_indirect_string (bfd *, gdb_byte *,
                                   const struct comp_unit_head *,
                                   unsigned int *);

static unsigned long read_unsigned_leb128 (bfd *, gdb_byte *, unsigned int *);

static long read_signed_leb128 (bfd *, gdb_byte *, unsigned int *);

static gdb_byte *skip_leb128 (bfd *, gdb_byte *);

static void set_cu_language (unsigned int, struct dwarf2_cu *);

static struct attribute *dwarf2_attr (struct die_info *, unsigned int,
                                      struct dwarf2_cu *);

static struct attribute *dwarf2_attr_no_follow (struct die_info *,
                                                unsigned int,
                                                struct dwarf2_cu *);

static int dwarf2_flag_true_p (struct die_info *die, unsigned name,
                               struct dwarf2_cu *cu);

static int die_is_declaration (struct die_info *, struct dwarf2_cu *cu);

static struct die_info *die_specification (struct die_info *die,
                                           struct dwarf2_cu **);

static void free_line_header (struct line_header *lh);

static void add_file_name (struct line_header *, char *, unsigned int,
                           unsigned int, unsigned int);

static struct line_header *(dwarf_decode_line_header
                            (unsigned int offset,
                             bfd *abfd, struct dwarf2_cu *cu));

static void dwarf_decode_lines (struct line_header *, char *, bfd *,
                                struct dwarf2_cu *, struct partial_symtab *);

static void dwarf2_start_subfile (char *, char *, char *);

static struct symbol *new_symbol (struct die_info *, struct type *,
                                  struct dwarf2_cu *);

static void dwarf2_const_value (struct attribute *, struct symbol *,
                                struct dwarf2_cu *);

static void dwarf2_const_value_data (struct attribute *attr,
                                     struct symbol *sym,
                                     int bits);

static struct type *die_type (struct die_info *, struct dwarf2_cu *);

static int need_gnat_info (struct dwarf2_cu *);

static struct type *die_descriptive_type (struct die_info *, struct dwarf2_cu *);

static void set_descriptive_type (struct type *, struct die_info *,
                                  struct dwarf2_cu *);

static struct type *die_containing_type (struct die_info *,
                                         struct dwarf2_cu *);

static struct type *tag_type_to_type (struct die_info *, struct dwarf2_cu *);

static struct type *read_type_die (struct die_info *, struct dwarf2_cu *);

static char *determine_prefix (struct die_info *die, struct dwarf2_cu *);

static char *typename_concat (struct obstack *obs, const char *prefix,
                              const char *suffix, int physname,
                              struct dwarf2_cu *cu);

static void read_file_scope (struct die_info *, struct dwarf2_cu *);

static void read_type_unit_scope (struct die_info *, struct dwarf2_cu *);

static void read_func_scope (struct die_info *, struct dwarf2_cu *);

static void read_lexical_block_scope (struct die_info *, struct dwarf2_cu *);

static int dwarf2_ranges_read (unsigned, CORE_ADDR *, CORE_ADDR *,
                               struct dwarf2_cu *, struct partial_symtab *);

static int dwarf2_get_pc_bounds (struct die_info *,
                                 CORE_ADDR *, CORE_ADDR *, struct dwarf2_cu *,
                                 struct partial_symtab *);

static void get_scope_pc_bounds (struct die_info *,
                                 CORE_ADDR *, CORE_ADDR *,
                                 struct dwarf2_cu *);

static void dwarf2_record_block_ranges (struct die_info *, struct block *,
                                        CORE_ADDR, struct dwarf2_cu *);

static void dwarf2_add_field (struct field_info *, struct die_info *,
                              struct dwarf2_cu *);

static void dwarf2_attach_fields_to_type (struct field_info *,
                                          struct type *, struct dwarf2_cu *);

static void dwarf2_add_member_fn (struct field_info *,
                                  struct die_info *, struct type *,
                                  struct dwarf2_cu *);

static void dwarf2_attach_fn_fields_to_type (struct field_info *,
                                             struct type *, struct dwarf2_cu *);

static void process_structure_scope (struct die_info *, struct dwarf2_cu *);

static void read_common_block (struct die_info *, struct dwarf2_cu *);

static void read_namespace (struct die_info *die, struct dwarf2_cu *);

static void read_module (struct die_info *die, struct dwarf2_cu *cu);

static void read_import_statement (struct die_info *die, struct dwarf2_cu *);

static struct type *read_module_type (struct die_info *die,
                                      struct dwarf2_cu *cu);

static const char *namespace_name (struct die_info *die,
                                   int *is_anonymous, struct dwarf2_cu *);

static void process_enumeration_scope (struct die_info *, struct dwarf2_cu *);

static CORE_ADDR decode_locdesc (struct dwarf_block *, struct dwarf2_cu *);

static enum dwarf_array_dim_ordering read_array_order (struct die_info *,
                                                       struct dwarf2_cu *);

static struct die_info *read_comp_unit (gdb_byte *, struct dwarf2_cu *);

static struct die_info *read_die_and_children_1 (const struct die_reader_specs *reader,
                                                 gdb_byte *info_ptr,
                                                 gdb_byte **new_info_ptr,
                                                 struct die_info *parent);

static struct die_info *read_die_and_children (const struct die_reader_specs *reader,
                                               gdb_byte *info_ptr,
                                               gdb_byte **new_info_ptr,
                                               struct die_info *parent);

static struct die_info *read_die_and_siblings (const struct die_reader_specs *reader,
                                               gdb_byte *info_ptr,
                                               gdb_byte **new_info_ptr,
                                               struct die_info *parent);

static gdb_byte *read_full_die (const struct die_reader_specs *reader,
                                struct die_info **, gdb_byte *,
                                int *);

static void process_die (struct die_info *, struct dwarf2_cu *);

static char *dwarf2_canonicalize_name (char *, struct dwarf2_cu *,
                                       struct obstack *);

static char *dwarf2_name (struct die_info *die, struct dwarf2_cu *);

static struct die_info *dwarf2_extension (struct die_info *die,
                                          struct dwarf2_cu **);

static char *dwarf_tag_name (unsigned int);

static char *dwarf_attr_name (unsigned int);

static char *dwarf_form_name (unsigned int);

static char *dwarf_bool_name (unsigned int);

static char *dwarf_type_encoding_name (unsigned int);

#if 0
static char *dwarf_cfi_name (unsigned int);
#endif

static struct die_info *sibling_die (struct die_info *);

static void dump_die_shallow (struct ui_file *, int indent, struct die_info *);

static void dump_die_for_error (struct die_info *);

static void dump_die_1 (struct ui_file *, int level, int max_level,
                        struct die_info *);

/*static*/ void dump_die (struct die_info *, int max_level);

static void store_in_ref_table (struct die_info *,
                                struct dwarf2_cu *);

static int is_ref_attr (struct attribute *);

static unsigned int dwarf2_get_ref_die_offset (struct attribute *);

static LONGEST dwarf2_get_attr_constant_value (struct attribute *, int);

static struct die_info *follow_die_ref_or_sig (struct die_info *,
                                               struct attribute *,
                                               struct dwarf2_cu **);

static struct die_info *follow_die_ref (struct die_info *,
                                        struct attribute *,
                                        struct dwarf2_cu **);

static struct die_info *follow_die_sig (struct die_info *,
                                        struct attribute *,
                                        struct dwarf2_cu **);

static void read_signatured_type_at_offset (struct objfile *objfile,
                                            unsigned int offset);

static void read_signatured_type (struct objfile *,
                                  struct signatured_type *type_sig);

/* memory allocation interface */

static struct dwarf_block *dwarf_alloc_block (struct dwarf2_cu *);

static struct abbrev_info *dwarf_alloc_abbrev (struct dwarf2_cu *);

static struct die_info *dwarf_alloc_die (struct dwarf2_cu *, int);

static void initialize_cu_func_list (struct dwarf2_cu *);

static void add_to_cu_func_list (const char *, CORE_ADDR, CORE_ADDR,
                                 struct dwarf2_cu *);

static void dwarf_decode_macros (struct line_header *, unsigned int,
                                 char *, bfd *, struct dwarf2_cu *);

static int attr_form_is_block (struct attribute *);

static int attr_form_is_section_offset (struct attribute *);

static int attr_form_is_constant (struct attribute *);

static void dwarf2_symbol_mark_computed (struct attribute *attr,
                                         struct symbol *sym,
                                         struct dwarf2_cu *cu);

static gdb_byte *skip_one_die (gdb_byte *buffer, gdb_byte *info_ptr,
                               struct abbrev_info *abbrev,
                               struct dwarf2_cu *cu);

static void free_stack_comp_unit (void *);

static hashval_t partial_die_hash (const void *item);

static int partial_die_eq (const void *item_lhs, const void *item_rhs);

static struct dwarf2_per_cu_data *dwarf2_find_containing_comp_unit
  (unsigned int offset, struct objfile *objfile);

static struct dwarf2_per_cu_data *dwarf2_find_comp_unit
  (unsigned int offset, struct objfile *objfile);

static struct dwarf2_cu *alloc_one_comp_unit (struct objfile *objfile);

static void free_one_comp_unit (void *);

static void free_cached_comp_units (void *);

static void age_cached_comp_units (void);

static void free_one_cached_comp_unit (void *);

static struct type *set_die_type (struct die_info *, struct type *,
                                  struct dwarf2_cu *);

static void create_all_comp_units (struct objfile *);

static void load_full_comp_unit (struct dwarf2_per_cu_data *,
                                 struct objfile *);

static void process_full_comp_unit (struct dwarf2_per_cu_data *);

static void dwarf2_add_dependence (struct dwarf2_cu *,
                                   struct dwarf2_per_cu_data *);

static void dwarf2_mark (struct dwarf2_cu *);

static void dwarf2_clear_marks (struct dwarf2_per_cu_data *);

static struct type *get_die_type (struct die_info *die, struct dwarf2_cu *cu);

static void dwarf2_release_queue (void *dummy);

static void queue_comp_unit (struct dwarf2_per_cu_data *per_cu,
                             struct objfile *objfile);

static void process_queue (struct objfile *objfile);

static void find_file_and_directory (struct die_info *die,
                                     struct dwarf2_cu *cu,
                                     char **name, char **comp_dir);

static char *file_full_name (int file, struct line_header *lh,
                             const char *comp_dir);

static gdb_byte *partial_read_comp_unit_head (struct comp_unit_head *header,
                                              gdb_byte *info_ptr,
                                              gdb_byte *buffer,
                                              unsigned int buffer_size,
                                              bfd *abfd);

static void init_cu_die_reader (struct die_reader_specs *reader,
                                struct dwarf2_cu *cu);

#if WORDS_BIGENDIAN

/* Convert VALUE between big- and little-endian.  */
static offset_type
byte_swap (offset_type value)
{
  offset_type result;

  result = (value & 0xff) << 24;
  result |= (value & 0xff00) << 8;
  result |= (value & 0xff0000) >> 8;
  result |= (value & 0xff000000) >> 24;
  return result;
}

#define MAYBE_SWAP(V)  byte_swap (V)

#else
#define MAYBE_SWAP(V) (V)
#endif /* WORDS_BIGENDIAN */

/* The suffix for an index file.  */
#define INDEX_SUFFIX ".gdb-index"

/* Try to locate the sections we need for DWARF 2 debugging
   information and return true if we have enough to do something.  */

int
dwarf2_has_info (struct objfile *objfile)
{
  dwarf2_per_objfile = objfile_data (objfile, dwarf2_objfile_data_key);
  if (!dwarf2_per_objfile)
    {
      /* Initialize per-objfile state.  */
      struct dwarf2_per_objfile *data
        = obstack_alloc (&objfile->objfile_obstack, sizeof (*data));

      memset (data, 0, sizeof (*data));
      set_objfile_data (objfile, dwarf2_objfile_data_key, data);
      dwarf2_per_objfile = data;

      bfd_map_over_sections (objfile->obfd, dwarf2_locate_sections, NULL);
      dwarf2_per_objfile->objfile = objfile;
    }
  return (dwarf2_per_objfile->info.asection != NULL
          && dwarf2_per_objfile->abbrev.asection != NULL);
}

/* When loading sections, we can either look for ".<name>", or for
 * ".z<name>", which indicates a compressed section.  */

static int
section_is_p (const char *section_name, const char *name)
{
  return (section_name[0] == '.'
          && (strcmp (section_name + 1, name) == 0
              || (section_name[1] == 'z'
                  && strcmp (section_name + 2, name) == 0)));
}

/* This function is mapped across the sections and remembers the
   offset and size of each of the debugging sections we are interested
   in.  */

static void
dwarf2_locate_sections (bfd *abfd, asection *sectp, void *ignore_ptr)
{
  if (section_is_p (sectp->name, INFO_SECTION))
    {
      dwarf2_per_objfile->info.asection = sectp;
      dwarf2_per_objfile->info.size = bfd_get_section_size (sectp);
    }
  else if (section_is_p (sectp->name, ABBREV_SECTION))
    {
      dwarf2_per_objfile->abbrev.asection = sectp;
      dwarf2_per_objfile->abbrev.size = bfd_get_section_size (sectp);
    }
  else if (section_is_p (sectp->name, LINE_SECTION))
    {
      dwarf2_per_objfile->line.asection = sectp;
      dwarf2_per_objfile->line.size = bfd_get_section_size (sectp);
    }
  else if (section_is_p (sectp->name, LOC_SECTION))
    {
      dwarf2_per_objfile->loc.asection = sectp;
      dwarf2_per_objfile->loc.size = bfd_get_section_size (sectp);
    }
  else if (section_is_p (sectp->name, MACINFO_SECTION))
    {
      dwarf2_per_objfile->macinfo.asection = sectp;
      dwarf2_per_objfile->macinfo.size = bfd_get_section_size (sectp);
    }
  else if (section_is_p (sectp->name, STR_SECTION))
    {
      dwarf2_per_objfile->str.asection = sectp;
      dwarf2_per_objfile->str.size = bfd_get_section_size (sectp);
    }
  else if (section_is_p (sectp->name, FRAME_SECTION))
    {
      dwarf2_per_objfile->frame.asection = sectp;
      dwarf2_per_objfile->frame.size = bfd_get_section_size (sectp);
    }
  else if (section_is_p (sectp->name, EH_FRAME_SECTION))
    {
      flagword aflag = bfd_get_section_flags (ignore_abfd, sectp);

      if (aflag & SEC_HAS_CONTENTS)
        {
          dwarf2_per_objfile->eh_frame.asection = sectp;
          dwarf2_per_objfile->eh_frame.size = bfd_get_section_size (sectp);
        }
    }
  else if (section_is_p (sectp->name, RANGES_SECTION))
    {
      dwarf2_per_objfile->ranges.asection = sectp;
      dwarf2_per_objfile->ranges.size = bfd_get_section_size (sectp);
    }
  else if (section_is_p (sectp->name, TYPES_SECTION))
    {
      dwarf2_per_objfile->types.asection = sectp;
      dwarf2_per_objfile->types.size = bfd_get_section_size (sectp);
    }
  else if (section_is_p (sectp->name, GDB_INDEX_SECTION))
    {
      dwarf2_per_objfile->gdb_index.asection = sectp;
      dwarf2_per_objfile->gdb_index.size = bfd_get_section_size (sectp);
    }

  if ((bfd_get_section_flags (abfd, sectp) & SEC_LOAD)
      && bfd_section_vma (abfd, sectp) == 0)
    dwarf2_per_objfile->has_section_at_zero = 1;
}

/* Decompress a section that was compressed using zlib.  Store the
   decompressed buffer, and its size, in OUTBUF and OUTSIZE.  */

static void
zlib_decompress_section (struct objfile *objfile, asection *sectp,
                         gdb_byte **outbuf, bfd_size_type *outsize)
{
  bfd *abfd = objfile->obfd;
#ifndef HAVE_ZLIB_H
  error (_("Support for zlib-compressed DWARF data (from '%s') "
           "is disabled in this copy of GDB"),
         bfd_get_filename (abfd));
#else
  bfd_size_type compressed_size = bfd_get_section_size (sectp);
  gdb_byte *compressed_buffer = xmalloc (compressed_size);
  struct cleanup *cleanup = make_cleanup (xfree, compressed_buffer);
  bfd_size_type uncompressed_size;
  gdb_byte *uncompressed_buffer;
  z_stream strm;
  int rc;
  int header_size = 12;

  if (bfd_seek (abfd, sectp->filepos, SEEK_SET) != 0
      || bfd_bread (compressed_buffer, compressed_size, abfd) != compressed_size)
    error (_("Dwarf Error: Can't read DWARF data from '%s'"),
           bfd_get_filename (abfd));

  /* Read the zlib header.  In this case, it should be "ZLIB" followed
     by the uncompressed section size, 8 bytes in big-endian order.  */
  if (compressed_size < header_size
      || strncmp (compressed_buffer, "ZLIB", 4) != 0)
    error (_("Dwarf Error: Corrupt DWARF ZLIB header from '%s'"),
           bfd_get_filename (abfd));
  uncompressed_size = compressed_buffer[4]; uncompressed_size <<= 8;
  uncompressed_size += compressed_buffer[5]; uncompressed_size <<= 8;
  uncompressed_size += compressed_buffer[6]; uncompressed_size <<= 8;
  uncompressed_size += compressed_buffer[7]; uncompressed_size <<= 8;
  uncompressed_size += compressed_buffer[8]; uncompressed_size <<= 8;
  uncompressed_size += compressed_buffer[9]; uncompressed_size <<= 8;
  uncompressed_size += compressed_buffer[10]; uncompressed_size <<= 8;
  uncompressed_size += compressed_buffer[11];

  /* It is possible the section consists of several compressed
     buffers concatenated together, so we uncompress in a loop.  */
  strm.zalloc = NULL;
  strm.zfree = NULL;
  strm.opaque = NULL;
  strm.avail_in = compressed_size - header_size;
  strm.next_in = (Bytef*) compressed_buffer + header_size;
  strm.avail_out = uncompressed_size;
  uncompressed_buffer = obstack_alloc (&objfile->objfile_obstack,
                                       uncompressed_size);
  rc = inflateInit (&strm);
  while (strm.avail_in > 0)
    {
      if (rc != Z_OK)
        error (_("Dwarf Error: setting up DWARF uncompression in '%s': %d"),
               bfd_get_filename (abfd), rc);
      strm.next_out = ((Bytef*) uncompressed_buffer
                       + (uncompressed_size - strm.avail_out));
      rc = inflate (&strm, Z_FINISH);
      if (rc != Z_STREAM_END)
        error (_("Dwarf Error: zlib error uncompressing from '%s': %d"),
               bfd_get_filename (abfd), rc);
      rc = inflateReset (&strm);
    }
  rc = inflateEnd (&strm);
  if (rc != Z_OK
      || strm.avail_out != 0)
    error (_("Dwarf Error: concluding DWARF uncompression in '%s': %d"),
           bfd_get_filename (abfd), rc);

  do_cleanups (cleanup);
  *outbuf = uncompressed_buffer;
  *outsize = uncompressed_size;
#endif
}

/* Read the contents of the section SECTP from object file specified by
   OBJFILE, store info about the section into INFO.
   If the section is compressed, uncompress it before returning.  */

static void
dwarf2_read_section (struct objfile *objfile, struct dwarf2_section_info *info)
{
  bfd *abfd = objfile->obfd;
  asection *sectp = info->asection;
  gdb_byte *buf, *retbuf;
  unsigned char header[4];

  if (info->readin)
    return;
  info->buffer = NULL;
  info->was_mmapped = 0;
  info->readin = 1;

  if (info->asection == NULL || info->size == 0)
    return;

  /* Check if the file has a 4-byte header indicating compression.  */
  if (info->size > sizeof (header)
      && bfd_seek (abfd, sectp->filepos, SEEK_SET) == 0
      && bfd_bread (header, sizeof (header), abfd) == sizeof (header))
    {
      /* Upon decompression, update the buffer and its size.  */
      if (strncmp (header, "ZLIB", sizeof (header)) == 0)
        {
          zlib_decompress_section (objfile, sectp, &info->buffer,
                                   &info->size);
          return;
        }
    }

#ifdef HAVE_MMAP
  if (pagesize == 0)
    pagesize = getpagesize ();

  /* Only try to mmap sections which are large enough: we don't want to
     waste space due to fragmentation.  Also, only try mmap for sections
     without relocations.  */

  if (info->size > 4 * pagesize && (sectp->flags & SEC_RELOC) == 0)
    {
      off_t pg_offset = sectp->filepos & ~(pagesize - 1);
      size_t map_length = info->size + sectp->filepos - pg_offset;
      caddr_t retbuf = bfd_mmap (abfd, 0, map_length, PROT_READ,
                                 MAP_PRIVATE, pg_offset);

      if (retbuf != MAP_FAILED)
        {
          info->was_mmapped = 1;
          info->buffer = retbuf + (sectp->filepos & (pagesize - 1)) ;
#if HAVE_POSIX_MADVISE
          posix_madvise (retbuf, map_length, POSIX_MADV_WILLNEED);
#endif
          return;
        }
    }
#endif

  /* If we get here, we are a normal, not-compressed section.  */
  info->buffer = buf
    = obstack_alloc (&objfile->objfile_obstack, info->size);

  /* When debugging .o files, we may need to apply relocations; see
     http://sourceware.org/ml/gdb-patches/2002-04/msg00136.html .
     We never compress sections in .o files, so we only need to
     try this when the section is not compressed.  */
  retbuf = symfile_relocate_debug_section (objfile, sectp, buf);
  if (retbuf != NULL)
    {
      info->buffer = retbuf;
      return;
    }

  if (bfd_seek (abfd, sectp->filepos, SEEK_SET) != 0
      || bfd_bread (buf, info->size, abfd) != info->size)
    error (_("Dwarf Error: Can't read DWARF data from '%s'"),
           bfd_get_filename (abfd));
}

/* Fill in SECTP, BUFP and SIZEP with section info, given OBJFILE and
   SECTION_NAME. */

void
dwarf2_get_section_info (struct objfile *objfile, const char *section_name,
                         asection **sectp, gdb_byte **bufp,
                         bfd_size_type *sizep)
{
  struct dwarf2_per_objfile *data
    = objfile_data (objfile, dwarf2_objfile_data_key);
  struct dwarf2_section_info *info;

  /* We may see an objfile without any DWARF, in which case we just
     return nothing.  */
  if (data == NULL)
    {
      *sectp = NULL;
      *bufp = NULL;
      *sizep = 0;
      return;
    }
  if (section_is_p (section_name, EH_FRAME_SECTION))
    info = &data->eh_frame;
  else if (section_is_p (section_name, FRAME_SECTION))
    info = &data->frame;
  else
    gdb_assert (0);

  if (info->asection != NULL && info->size != 0 && info->buffer == NULL)
    /* We haven't read this section in yet.  Do it now.  */
    dwarf2_read_section (objfile, info);

  *sectp = info->asection;
  *bufp = info->buffer;
  *sizep = info->size;
}

\f

/* Read in the symbols for PER_CU.  OBJFILE is the objfile from which
   this CU came.  */
static void
dw2_do_instantiate_symtab (struct objfile *objfile,
                           struct dwarf2_per_cu_data *per_cu)
{
  struct cleanup *back_to;

  back_to = make_cleanup (dwarf2_release_queue, NULL);

  queue_comp_unit (per_cu, objfile);

  if (per_cu->from_debug_types)
    read_signatured_type_at_offset (objfile, per_cu->offset);
  else
    load_full_comp_unit (per_cu, objfile);

  process_queue (objfile);

  /* Age the cache, releasing compilation units that have not
     been used recently.  */
  age_cached_comp_units ();

  do_cleanups (back_to);
}

/* Ensure that the symbols for PER_CU have been read in.  OBJFILE is
   the objfile from which this CU came.  Returns the resulting symbol
   table.  */
static struct symtab *
dw2_instantiate_symtab (struct objfile *objfile,
                        struct dwarf2_per_cu_data *per_cu)
{
  if (!per_cu->v.quick->symtab)
    {
      struct cleanup *back_to = make_cleanup (free_cached_comp_units, NULL);
      increment_reading_symtab ();
      dw2_do_instantiate_symtab (objfile, per_cu);
      do_cleanups (back_to);
    }
  return per_cu->v.quick->symtab;
}

/* A helper function that knows how to read a 64-bit value in a way
   that doesn't make gdb die.  Returns 1 if the conversion went ok, 0
   otherwise.  */
static int
extract_cu_value (const char *bytes, ULONGEST *result)
{
  if (sizeof (ULONGEST) < 8)
    {
      int i;

      /* Ignore the upper 4 bytes if they are all zero.  */
      for (i = 0; i < 4; ++i)
        if (bytes[i + 4] != 0)
          return 0;

      *result = extract_unsigned_integer (bytes, 4, BFD_ENDIAN_LITTLE);
    }
  else
    *result = extract_unsigned_integer (bytes, 8, BFD_ENDIAN_LITTLE);
  return 1;
}

/* Read the CU list from the mapped index, and use it to create all
   the CU objects for this objfile.  Return 0 if something went wrong,
   1 if everything went ok.  */
static int
create_cus_from_index (struct objfile *objfile, struct mapped_index *index,
                       const gdb_byte *cu_list, offset_type cu_list_elements)
{
  offset_type i;
  const char *entry;

  dwarf2_per_objfile->n_comp_units = cu_list_elements / 2;
  dwarf2_per_objfile->all_comp_units
    = obstack_alloc (&objfile->objfile_obstack,
                     dwarf2_per_objfile->n_comp_units
                     * sizeof (struct dwarf2_per_cu_data *));

  for (i = 0; i < cu_list_elements; i += 2)
    {
      struct dwarf2_per_cu_data *the_cu;
      ULONGEST offset, length;

      if (!extract_cu_value (cu_list, &offset)
          || !extract_cu_value (cu_list + 8, &length))
        return 0;
      cu_list += 2 * 8;

      the_cu = OBSTACK_ZALLOC (&objfile->objfile_obstack,
                               struct dwarf2_per_cu_data);
      the_cu->offset = offset;
      the_cu->length = length;
      the_cu->objfile = objfile;
      the_cu->v.quick = OBSTACK_ZALLOC (&objfile->objfile_obstack,
                                        struct dwarf2_per_cu_quick_data);
      dwarf2_per_objfile->all_comp_units[i / 2] = the_cu;
    }

  return 1;
}

/* Read the address map data from the mapped index, and use it to
   populate the objfile's psymtabs_addrmap.  */
static void
create_addrmap_from_index (struct objfile *objfile, struct mapped_index *index)
{
  const gdb_byte *iter, *end;
  struct obstack temp_obstack;
  struct addrmap *mutable_map;
  struct cleanup *cleanup;
  CORE_ADDR baseaddr;

  obstack_init (&temp_obstack);
  cleanup = make_cleanup_obstack_free (&temp_obstack);
  mutable_map = addrmap_create_mutable (&temp_obstack);

  iter = index->address_table;
  end = iter + index->address_table_size;

  baseaddr = ANOFFSET (objfile->section_offsets, SECT_OFF_TEXT (objfile));

  while (iter < end)
    {
      ULONGEST hi, lo, cu_index;
      lo = extract_unsigned_integer (iter, 8, BFD_ENDIAN_LITTLE);
      iter += 8;
      hi = extract_unsigned_integer (iter, 8, BFD_ENDIAN_LITTLE);
      iter += 8;
      cu_index = extract_unsigned_integer (iter, 4, BFD_ENDIAN_LITTLE);
      iter += 4;
      
      addrmap_set_empty (mutable_map, lo + baseaddr, hi + baseaddr - 1,
                         dwarf2_per_objfile->all_comp_units[cu_index]);
    }

  objfile->psymtabs_addrmap = addrmap_create_fixed (mutable_map,
                                                    &objfile->objfile_obstack);
  do_cleanups (cleanup);
}

/* The hash function for strings in the mapped index.  This is the
   same as the hashtab.c hash function, but we keep a separate copy to
   maintain control over the implementation.  This is necessary
   because the hash function is tied to the format of the mapped index
   file.  */
static hashval_t
mapped_index_string_hash (const void *p)
{
  const unsigned char *str = (const unsigned char *) p;
  hashval_t r = 0;
  unsigned char c;

  while ((c = *str++) != 0)
    r = r * 67 + c - 113;

  return r;
}

/* Find a slot in the mapped index INDEX for the object named NAME.
   If NAME is found, set *VEC_OUT to point to the CU vector in the
   constant pool and return 1.  If NAME cannot be found, return 0.  */
static int
find_slot_in_mapped_hash (struct mapped_index *index, const char *name,
                          offset_type **vec_out)
{
  offset_type hash = mapped_index_string_hash (name);
  offset_type slot, step;

  slot = hash & (index->index_table_slots - 1);
  step = ((hash * 17) & (index->index_table_slots - 1)) | 1;

  for (;;)
    {
      /* Convert a slot number to an offset into the table.  */
      offset_type i = 2 * slot;
      const char *str;
      if (index->index_table[i] == 0 && index->index_table[i + 1] == 0)
        return 0;

      str = index->constant_pool + MAYBE_SWAP (index->index_table[i]);
      if (!strcmp (name, str))
        {
          *vec_out = (offset_type *) (index->constant_pool
                                      + MAYBE_SWAP (index->index_table[i + 1]));
          return 1;
        }

      slot = (slot + step) & (index->index_table_slots - 1);
    }
}

/* Read the index file.  If everything went ok, initialize the "quick"
   elements of all the CUs and return 1.  Otherwise, return 0.  */
static int
dwarf2_read_index (struct objfile *objfile)
{
  struct stat st, obstat;
  int fd;
  char *addr;
  struct mapped_index *map;
  offset_type val, *metadata;
  char buf1[8], buf2[8];
  const gdb_byte *cu_list;
  offset_type cu_list_elements;

  if (dwarf2_per_objfile->gdb_index.asection == NULL
      || dwarf2_per_objfile->gdb_index.size == 0)
    return 0;
  dwarf2_read_section (objfile, &dwarf2_per_objfile->gdb_index);

  addr = dwarf2_per_objfile->gdb_index.buffer;
  /* Version check.  */
  if (MAYBE_SWAP (*(offset_type *) addr) != 1)
    return 0;

  map = OBSTACK_ZALLOC (&objfile->objfile_obstack, struct mapped_index);
  map->total_size = st.st_size;

  metadata = (offset_type *) (addr + sizeof (offset_type));
  cu_list = addr + MAYBE_SWAP (metadata[0]);
  cu_list_elements = ((MAYBE_SWAP (metadata[1]) - MAYBE_SWAP (metadata[0]))
                      / 8);
  map->address_table = addr + MAYBE_SWAP (metadata[1]);
  map->address_table_size = (MAYBE_SWAP (metadata[2])
                             - MAYBE_SWAP (metadata[1]));
  map->index_table = (offset_type *) (addr + MAYBE_SWAP (metadata[2]));
  map->index_table_slots = ((MAYBE_SWAP (metadata[3])
                             - MAYBE_SWAP (metadata[2]))
                            / (2 * sizeof (offset_type)));
  map->constant_pool = addr + MAYBE_SWAP (metadata[3]);

  if (!create_cus_from_index (objfile, map, cu_list, cu_list_elements))
    return 0;

  create_addrmap_from_index (objfile, map);

  dwarf2_per_objfile->index_table = map;
  dwarf2_per_objfile->using_index = 1;

  return 1;
}

/* A helper for the "quick" functions which sets the global
   dwarf2_per_objfile according to OBJFILE.  */
static void
dw2_setup (struct objfile *objfile)
{
  dwarf2_per_objfile = objfile_data (objfile, dwarf2_objfile_data_key);
  gdb_assert (dwarf2_per_objfile);
}

/* A helper for the "quick" functions which attempts to read the line
   table for THIS_CU.  */
static void
dw2_require_line_header (struct objfile *objfile,
                         struct dwarf2_per_cu_data *this_cu)
{
  bfd *abfd = objfile->obfd;
  struct line_header *lh = NULL;
  struct attribute *attr;
  struct cleanup *cleanups;
  struct die_info *comp_unit_die;
  gdb_byte *beg_of_comp_unit, *info_ptr, *buffer;
  int has_children, i;
  struct dwarf2_cu cu;
  unsigned int bytes_read, buffer_size;
  struct die_reader_specs reader_specs;
  char *name, *comp_dir;

  if (this_cu->v.quick->read_lines)
    return;
  this_cu->v.quick->read_lines = 1;

  memset (&cu, 0, sizeof (cu));
  cu.objfile = objfile;
  obstack_init (&cu.comp_unit_obstack);

  cleanups = make_cleanup (free_stack_comp_unit, &cu);

  dwarf2_read_section (objfile, &dwarf2_per_objfile->info);
  buffer_size = dwarf2_per_objfile->info.size;
  buffer = dwarf2_per_objfile->info.buffer;
  info_ptr = buffer + this_cu->offset;
  beg_of_comp_unit = info_ptr;

  info_ptr = partial_read_comp_unit_head (&cu.header, info_ptr,
                                          buffer, buffer_size,
                                          abfd);

  /* Complete the cu_header.  */
  cu.header.offset = beg_of_comp_unit - buffer;
  cu.header.first_die_offset = info_ptr - beg_of_comp_unit;

  this_cu->cu = &cu;
  cu.per_cu = this_cu;

  dwarf2_read_abbrevs (abfd, &cu);
  make_cleanup (dwarf2_free_abbrev_table, &cu);

  if (this_cu->from_debug_types)
    info_ptr += 8 /*signature*/ + cu.header.offset_size;
  init_cu_die_reader (&reader_specs, &cu);
  info_ptr = read_full_die (&reader_specs, &comp_unit_die, info_ptr,
                            &has_children);

  attr = dwarf2_attr (comp_unit_die, DW_AT_stmt_list, &cu);
  if (attr)
    {
      unsigned int line_offset = DW_UNSND (attr);
      lh = dwarf_decode_line_header (line_offset, abfd, &cu);
    }
  if (lh == NULL)
    {
      do_cleanups (cleanups);
      return;
    }

  find_file_and_directory (comp_unit_die, &cu, &name, &comp_dir);

  this_cu->v.quick->lines = lh;

  this_cu->v.quick->file_names
    = obstack_alloc (&objfile->objfile_obstack,
                     lh->num_file_names * sizeof (char *));
  for (i = 0; i < lh->num_file_names; ++i)
    this_cu->v.quick->file_names[i] = file_full_name (i + 1, lh, comp_dir);

  do_cleanups (cleanups);
}

/* A helper for the "quick" functions which computes and caches the
   real path for a given file name from the line table.
   dw2_require_line_header must have been called before this is
   invoked.  */
static const char *
dw2_require_full_path (struct objfile *objfile,
                       struct dwarf2_per_cu_data *cu,
                       int index)
{
  if (!cu->v.quick->full_names)
    cu->v.quick->full_names
      = OBSTACK_CALLOC (&objfile->objfile_obstack,
                        cu->v.quick->lines->num_file_names,
                        sizeof (char *));

  if (!cu->v.quick->full_names[index])
    cu->v.quick->full_names[index]
      = gdb_realpath (cu->v.quick->file_names[index]);

  return cu->v.quick->full_names[index];
}

static struct symtab *
dw2_find_last_source_symtab (struct objfile *objfile)
{
  int index;
  dw2_setup (objfile);
  index = dwarf2_per_objfile->n_comp_units - 1;
  return dw2_instantiate_symtab (objfile,
                                 dwarf2_per_objfile->all_comp_units[index]);
}

static void
dw2_forget_cached_source_info (struct objfile *objfile)
{
  int i;

  dw2_setup (objfile);
  for (i = 0; i < dwarf2_per_objfile->n_comp_units; ++i)
    {
      struct dwarf2_per_cu_data *cu = dwarf2_per_objfile->all_comp_units[i];

      if (cu->v.quick->full_names)
        {
          int j;

          for (j = 0; j < cu->v.quick->lines->num_file_names; ++j)
            xfree ((void *) cu->v.quick->full_names[j]);
        }
    }
}

static int
dw2_lookup_symtab (struct objfile *objfile, const char *name,
                   const char *full_path, const char *real_path,
                   struct symtab **result)
{
  int i;
  int check_basename = lbasename (name) == name;
  struct dwarf2_per_cu_data *base_cu = NULL;

  dw2_setup (objfile);
  for (i = 0; i < dwarf2_per_objfile->n_comp_units; ++i)
    {
      int j;
      struct dwarf2_per_cu_data *cu = dwarf2_per_objfile->all_comp_units[i];

      if (cu->v.quick->symtab)
        continue;

      dw2_require_line_header (objfile, cu);
      if (!cu->v.quick->lines)
        continue;

      for (j = 0; j < cu->v.quick->lines->num_file_names; ++j)
        {
          const char *this_name = cu->v.quick->file_names[j];

          if (FILENAME_CMP (name, this_name) == 0)
            {
              *result = dw2_instantiate_symtab (objfile, cu);
              return 1;
            }

          if (check_basename && ! base_cu
              && FILENAME_CMP (lbasename (this_name), name) == 0)
            base_cu = cu;

          if (full_path != NULL)
            {
              const char *this_full_name = dw2_require_full_path (objfile,
                                                                  cu, j);

              if (this_full_name
                  && FILENAME_CMP (full_path, this_full_name) == 0)
                {
                  *result = dw2_instantiate_symtab (objfile, cu);
                  return 1;
                }
            }

          if (real_path != NULL)
            {
              const char *this_full_name = dw2_require_full_path (objfile,
                                                                  cu, j);

              if (this_full_name != NULL)
                {
                  char *rp = gdb_realpath (this_full_name);
                  if (rp != NULL && FILENAME_CMP (real_path, rp) == 0)
                    {
                      xfree (rp);
                      *result = dw2_instantiate_symtab (objfile, cu);
                      return 1;
                    }
                  xfree (rp);
                }
            }
        }
    }

  if (base_cu)
    {
      *result = dw2_instantiate_symtab (objfile, base_cu);
      return 1;
    }

  return 0;
}

static struct symtab *
dw2_lookup_symbol (struct objfile *objfile, int block_index,
                   const char *name, domain_enum domain)
{
  /* We do all the work in the pre_expand_symtabs_matching hook
     instead.  */
  return NULL;
}

/* A helper function that expands all symtabs that hold an object
   named NAME.  */
static void
dw2_do_expand_symtabs_matching (struct objfile *objfile, const char *name)
{
  dw2_setup (objfile);

  if (dwarf2_per_objfile->index_table)
    {
      offset_type *vec;

      if (find_slot_in_mapped_hash (dwarf2_per_objfile->index_table,
                                    name, &vec))
        {
          offset_type i, len = MAYBE_SWAP (*vec);
          for (i = 0; i < len; ++i)
            {
              offset_type cu_index = MAYBE_SWAP (vec[i + 1]);
              struct dwarf2_per_cu_data *cu;
              cu = dwarf2_per_objfile->all_comp_units[cu_index];
              dw2_instantiate_symtab (objfile, cu);
            }
        }
    }
}

static void
dw2_pre_expand_symtabs_matching (struct objfile *objfile,
                                 int kind, const char *name,
                                 domain_enum domain)
{
  dw2_do_expand_symtabs_matching (objfile, name);
}

static void
dw2_print_stats (struct objfile *objfile)
{
  int i, count;

  dw2_setup (objfile);
  count = 0;
  for (i = 0; i < dwarf2_per_objfile->n_comp_units; ++i)
    {
      struct dwarf2_per_cu_data *cu = dwarf2_per_objfile->all_comp_units[i];

      if (!cu->v.quick->symtab)
        ++count;
    }
  printf_filtered (_("  Number of unread CUs: %d\n"), count);
}

static void
dw2_dump (struct objfile *objfile)
{
  /* Nothing worth printing.  */
}

static void
dw2_relocate (struct objfile *objfile, struct section_offsets *new_offsets,
              struct section_offsets *delta)
{
  /* There's nothing to relocate here.  */
}

static void
dw2_expand_symtabs_for_function (struct objfile *objfile,
                                 const char *func_name)
{
  dw2_do_expand_symtabs_matching (objfile, func_name);
}

static void
dw2_expand_all_symtabs (struct objfile *objfile)
{
  int i;

  dw2_setup (objfile);
  for (i = 0; i < dwarf2_per_objfile->n_comp_units; ++i)
    {
      struct dwarf2_per_cu_data *cu = dwarf2_per_objfile->all_comp_units[i];

      dw2_instantiate_symtab (objfile, cu);
    }
}

static void
dw2_expand_symtabs_with_filename (struct objfile *objfile,
                                  const char *filename)
{
  int i;

  dw2_setup (objfile);
  for (i = 0; i < dwarf2_per_objfile->n_comp_units; ++i)
    {
      int j;
      struct dwarf2_per_cu_data *cu = dwarf2_per_objfile->all_comp_units[i];

      if (cu->v.quick->symtab)
        continue;

      dw2_require_line_header (objfile, cu);
      if (!cu->v.quick->lines)
        continue;

      for (j = 0; j < cu->v.quick->lines->num_file_names; ++j)
        {
          const char *this_name = cu->v.quick->file_names[j];
          if (strcmp (this_name, filename) == 0)
            {
              dw2_instantiate_symtab (objfile, cu);
              break;
            }
        }
    }
}

static char *
dw2_find_symbol_file (struct objfile *objfile, const char *name)
{
  struct dwarf2_per_cu_data *cu;
  offset_type *vec;

  dw2_setup (objfile);

  if (!dwarf2_per_objfile->index_table)
    return NULL;

  if (!find_slot_in_mapped_hash (dwarf2_per_objfile->index_table,
                                 name, &vec))
    return NULL;

  /* Note that this just looks at the very first one named NAME -- but
     actually we are looking for a function.  find_main_filename
     should be rewritten so that it doesn't require a custom hook.  It
     could just use the ordinary symbol tables.  */
  /* vec[0] is the length, which must always be >0.  */
  cu = dwarf2_per_objfile->all_comp_units[MAYBE_SWAP (vec[1])];

  dw2_require_line_header (objfile, cu);
  if (!cu->v.quick->lines)
    return NULL;

  return (char *) cu->v.quick->file_names[cu->v.quick->lines->num_file_names
                                          - 1];
}

static void
dw2_map_ada_symtabs (struct objfile *objfile,
                     int (*wild_match) (const char *, int, const char *),
                     int (*is_name_suffix) (const char *),
                     void (*callback) (struct objfile *,
                                       struct symtab *, void *),
                     const char *name, int global,
                     domain_enum namespace, int wild,
                     void *data)
{
  /* For now, we don't support Ada, so this function can't be
     reached.  */
  internal_error (__FILE__, __LINE__,
                  _("map_ada_symtabs called via index method"));
}

static void
dw2_expand_symtabs_matching (struct objfile *objfile,
                             int (*file_matcher) (const char *, void *),
                             int (*name_matcher) (const char *, void *),
                             domain_enum kind,
                             void *data)
{
  int i;
  offset_type iter;

  dw2_setup (objfile);
  if (!dwarf2_per_objfile->index_table)
    return;

  for (i = 0; i < dwarf2_per_objfile->n_comp_units; ++i)
    {
      int j;
      struct dwarf2_per_cu_data *cu = dwarf2_per_objfile->all_comp_units[i];

      cu->v.quick->mark = 0;
      if (cu->v.quick->symtab)
        continue;

      dw2_require_line_header (objfile, cu);
      if (!cu->v.quick->lines)
        continue;

      for (j = 0; j < cu->v.quick->lines->num_file_names; ++j)
        {
          if (file_matcher (cu->v.quick->file_names[j], data))
            {
              cu->v.quick->mark = 1;
              break;
            }
        }
    }

  for (iter = 0;
       iter < dwarf2_per_objfile->index_table->index_table_slots;
       ++iter)
    {
      offset_type idx = 2 * iter;
      const char *name;
      offset_type *vec, vec_len, vec_idx;

      if (dwarf2_per_objfile->index_table->index_table[idx] == 0
          && dwarf2_per_objfile->index_table->index_table[idx + 1] == 0)
        continue;

      name = (dwarf2_per_objfile->index_table->constant_pool
              + dwarf2_per_objfile->index_table->index_table[idx]);

      if (! (*name_matcher) (name, data))
        continue;

      /* The name was matched, now expand corresponding CUs that were
         marked.  */
      vec = (offset_type *) (dwarf2_per_objfile->index_table->constant_pool
                             + dwarf2_per_objfile->index_table->index_table[idx + 1]);
      vec_len = MAYBE_SWAP (vec[0]);
      for (vec_idx = 0; vec_idx < vec_len; ++vec_idx)
        {
          struct dwarf2_per_cu_data *cu
            = dwarf2_per_objfile->all_comp_units[MAYBE_SWAP (vec[vec_idx + 1])];
          if (cu->v.quick->mark)
            dw2_instantiate_symtab (objfile, cu);
        }
    }
}

static struct symtab *
dw2_find_pc_sect_symtab (struct objfile *objfile,
                         struct minimal_symbol *msymbol,
                         CORE_ADDR pc,
                         struct obj_section *section,
                         int warn_if_readin)
{
  struct dwarf2_per_cu_data *data;

  dw2_setup (objfile);

  if (!objfile->psymtabs_addrmap)
    return NULL;

  data = addrmap_find (objfile->psymtabs_addrmap, pc);
  if (!data)
    return NULL;

  if (warn_if_readin && data->v.quick->symtab)
    warning (_("(Internal error: pc %s in read in CU, but not in symtab.)\n"),
             paddress (get_objfile_arch (objfile), pc));

  return dw2_instantiate_symtab (objfile, data);
}

static void
dw2_map_symbol_names (struct objfile *objfile,
                      void (*fun) (const char *, void *),
                      void *data)
{
  offset_type iter;
  dw2_setup (objfile);

  if (!dwarf2_per_objfile->index_table)
    return;

  for (iter = 0;
       iter < dwarf2_per_objfile->index_table->index_table_slots;
       ++iter)
    {
      offset_type idx = 2 * iter;
      const char *name;
      offset_type *vec, vec_len, vec_idx;

      if (dwarf2_per_objfile->index_table->index_table[idx] == 0
          && dwarf2_per_objfile->index_table->index_table[idx + 1] == 0)
        continue;

      name = (dwarf2_per_objfile->index_table->constant_pool
              + dwarf2_per_objfile->index_table->index_table[idx]);

      (*fun) (name, data);
    }
}

static void
dw2_map_symbol_filenames (struct objfile *objfile,
                          void (*fun) (const char *, const char *, void *),
                          void *data)
{
  int i;

  dw2_setup (objfile);
  for (i = 0; i < dwarf2_per_objfile->n_comp_units; ++i)
    {
      int j;
      struct dwarf2_per_cu_data *cu = dwarf2_per_objfile->all_comp_units[i];

      if (cu->v.quick->symtab)
        continue;

      dw2_require_line_header (objfile, cu);
      if (!cu->v.quick->lines)
        continue;

      for (j = 0; j < cu->v.quick->lines->num_file_names; ++j)
        {
          const char *this_full_name = dw2_require_full_path (objfile, cu, j);
          (*fun) (cu->v.quick->file_names[j], this_full_name, data);
        }
    }
}

static int
dw2_has_symbols (struct objfile *objfile)
{
  return 1;
}

const struct quick_symbol_functions dwarf2_gdb_index_functions =
{
  dw2_has_symbols,
  dw2_find_last_source_symtab,
  dw2_forget_cached_source_info,
  dw2_lookup_symtab,
  dw2_lookup_symbol,
  dw2_pre_expand_symtabs_matching,
  dw2_print_stats,
  dw2_dump,
  dw2_relocate,
  dw2_expand_symtabs_for_function,
  dw2_expand_all_symtabs,
  dw2_expand_symtabs_with_filename,
  dw2_find_symbol_file,
  dw2_map_ada_symtabs,
  dw2_expand_symtabs_matching,
  dw2_find_pc_sect_symtab,
  dw2_map_symbol_names,
  dw2_map_symbol_filenames
};

/* Initialize for reading DWARF for this objfile.  Return 0 if this
   file will use psymtabs, or 1 if using the GNU index.  */

int
dwarf2_initialize_objfile (struct objfile *objfile)
{
  /* If we're about to read full symbols, don't bother with the
     indices.  In this case we also don't care if some other debug
     format is making psymtabs, because they are all about to be
     expanded anyway.  */
  if ((objfile->flags & OBJF_READNOW))
    {
      int i;

      dwarf2_per_objfile->using_index = 1;
      create_all_comp_units (objfile);

      for (i = 0; i < dwarf2_per_objfile->n_comp_units; ++i)
        {
          struct dwarf2_per_cu_data *cu = dwarf2_per_objfile->all_comp_units[i];

          cu->v.quick = OBSTACK_ZALLOC (&objfile->objfile_obstack,
                                        struct dwarf2_per_cu_quick_data);
        }

      /* Return 1 so that gdb sees the "quick" functions.  However,
         these functions will be no-ops because we will have expanded
         all symtabs.  */
      return 1;
    }

  if (dwarf2_read_index (objfile))
    return 1;

  dwarf2_build_psymtabs (objfile);
  return 0;
}

\f

/* Build a partial symbol table.  */

void
dwarf2_build_psymtabs (struct objfile *objfile)
{
  if (objfile->global_psymbols.size == 0 && objfile->static_psymbols.size == 0)
    {
      init_psymbol_list (objfile, 1024);
    }

  dwarf2_build_psymtabs_hard (objfile);
}

/* Return TRUE if OFFSET is within CU_HEADER.  */

static inline int
offset_in_cu_p (const struct comp_unit_head *cu_header, unsigned int offset)
{
  unsigned int bottom = cu_header->offset;
  unsigned int top = (cu_header->offset
                      + cu_header->length
                      + cu_header->initial_length_size);

  return (offset >= bottom && offset < top);
}

/* Read in the comp unit header information from the debug_info at info_ptr.
   NOTE: This leaves members offset, first_die_offset to be filled in
   by the caller.  */

static gdb_byte *
read_comp_unit_head (struct comp_unit_head *cu_header,
                     gdb_byte *info_ptr, bfd *abfd)
{
  int signed_addr;
  unsigned int bytes_read;

  cu_header->length = read_initial_length (abfd, info_ptr, &bytes_read);
  cu_header->initial_length_size = bytes_read;
  cu_header->offset_size = (bytes_read == 4) ? 4 : 8;
  info_ptr += bytes_read;
  cu_header->version = read_2_bytes (abfd, info_ptr);
  info_ptr += 2;
  cu_header->abbrev_offset = read_offset (abfd, info_ptr, cu_header,
                                          &bytes_read);
  info_ptr += bytes_read;
  cu_header->addr_size = read_1_byte (abfd, info_ptr);
  info_ptr += 1;
  signed_addr = bfd_get_sign_extend_vma (abfd);
  if (signed_addr < 0)
    internal_error (__FILE__, __LINE__,
                    _("read_comp_unit_head: dwarf from non elf file"));
  cu_header->signed_addr_p = signed_addr;

  return info_ptr;
}

static gdb_byte *
partial_read_comp_unit_head (struct comp_unit_head *header, gdb_byte *info_ptr,
                             gdb_byte *buffer, unsigned int buffer_size,
                             bfd *abfd)
{
  gdb_byte *beg_of_comp_unit = info_ptr;

  info_ptr = read_comp_unit_head (header, info_ptr, abfd);

  if (header->version != 2 && header->version != 3 && header->version != 4)
    error (_("Dwarf Error: wrong version in compilation unit header "
           "(is %d, should be 2, 3, or 4) [in module %s]"), header->version,
           bfd_get_filename (abfd));

  if (header->abbrev_offset >= dwarf2_per_objfile->abbrev.size)
    error (_("Dwarf Error: bad offset (0x%lx) in compilation unit header "
           "(offset 0x%lx + 6) [in module %s]"),
           (long) header->abbrev_offset,
           (long) (beg_of_comp_unit - buffer),
           bfd_get_filename (abfd));

  if (beg_of_comp_unit + header->length + header->initial_length_size
      > buffer + buffer_size)
    error (_("Dwarf Error: bad length (0x%lx) in compilation unit header "
           "(offset 0x%lx + 0) [in module %s]"),
           (long) header->length,
           (long) (beg_of_comp_unit - buffer),
           bfd_get_filename (abfd));

  return info_ptr;
}

/* Read in the types comp unit header information from .debug_types entry at
   types_ptr.  The result is a pointer to one past the end of the header.  */

static gdb_byte *
read_type_comp_unit_head (struct comp_unit_head *cu_header,
                          ULONGEST *signature,
                          gdb_byte *types_ptr, bfd *abfd)
{
  gdb_byte *initial_types_ptr = types_ptr;

  dwarf2_read_section (dwarf2_per_objfile->objfile,
                       &dwarf2_per_objfile->types);
  cu_header->offset = types_ptr - dwarf2_per_objfile->types.buffer;

  types_ptr = read_comp_unit_head (cu_header, types_ptr, abfd);

  *signature = read_8_bytes (abfd, types_ptr);
  types_ptr += 8;
  types_ptr += cu_header->offset_size;
  cu_header->first_die_offset = types_ptr - initial_types_ptr;

  return types_ptr;
}

/* Allocate a new partial symtab for file named NAME and mark this new
   partial symtab as being an include of PST.  */

static void
dwarf2_create_include_psymtab (char *name, struct partial_symtab *pst,
                               struct objfile *objfile)
{
  struct partial_symtab *subpst = allocate_psymtab (name, objfile);

  subpst->section_offsets = pst->section_offsets;
  subpst->textlow = 0;
  subpst->texthigh = 0;

  subpst->dependencies = (struct partial_symtab **)
    obstack_alloc (&objfile->objfile_obstack,
                   sizeof (struct partial_symtab *));
  subpst->dependencies[0] = pst;
  subpst->number_of_dependencies = 1;

  subpst->globals_offset = 0;
  subpst->n_global_syms = 0;
  subpst->statics_offset = 0;
  subpst->n_static_syms = 0;
  subpst->symtab = NULL;
  subpst->read_symtab = pst->read_symtab;
  subpst->readin = 0;

  /* No private part is necessary for include psymtabs.  This property
     can be used to differentiate between such include psymtabs and
     the regular ones.  */
  subpst->read_symtab_private = NULL;
}

/* Read the Line Number Program data and extract the list of files
   included by the source file represented by PST.  Build an include
   partial symtab for each of these included files.  */

static void
dwarf2_build_include_psymtabs (struct dwarf2_cu *cu,
                               struct die_info *die,
                               struct partial_symtab *pst)
{
  struct objfile *objfile = cu->objfile;
  bfd *abfd = objfile->obfd;
  struct line_header *lh = NULL;
  struct attribute *attr;

  attr = dwarf2_attr (die, DW_AT_stmt_list, cu);
  if (attr)
    {
      unsigned int line_offset = DW_UNSND (attr);

      lh = dwarf_decode_line_header (line_offset, abfd, cu);
    }
  if (lh == NULL)
    return;  /* No linetable, so no includes.  */

  dwarf_decode_lines (lh, NULL, abfd, cu, pst);

  free_line_header (lh);
}

static hashval_t
hash_type_signature (const void *item)
{
  const struct signatured_type *type_sig = item;

  /* This drops the top 32 bits of the signature, but is ok for a hash.  */
  return type_sig->signature;
}

static int
eq_type_signature (const void *item_lhs, const void *item_rhs)
{
  const struct signatured_type *lhs = item_lhs;
  const struct signatured_type *rhs = item_rhs;

  return lhs->signature == rhs->signature;
}

/* Create the hash table of all entries in the .debug_types section.
   The result is zero if there is an error (e.g. missing .debug_types section),
   otherwise non-zero.  */

static int
create_debug_types_hash_table (struct objfile *objfile)
{
  gdb_byte *info_ptr;
  htab_t types_htab;

  dwarf2_read_section (objfile, &dwarf2_per_objfile->types);
  info_ptr = dwarf2_per_objfile->types.buffer;

  if (info_ptr == NULL)
    {
      dwarf2_per_objfile->signatured_types = NULL;
      return 0;
    }

  types_htab = htab_create_alloc_ex (41,
                                     hash_type_signature,
                                     eq_type_signature,
                                     NULL,
                                     &objfile->objfile_obstack,
                                     hashtab_obstack_allocate,
                                     dummy_obstack_deallocate);

  if (dwarf2_die_debug)
    fprintf_unfiltered (gdb_stdlog, "Signatured types:\n");

  while (info_ptr < dwarf2_per_objfile->types.buffer + dwarf2_per_objfile->types.size)
    {
      unsigned int offset;
      unsigned int offset_size;
      unsigned int type_offset;
      unsigned int length, initial_length_size;
      unsigned short version;
      ULONGEST signature;
      struct signatured_type *type_sig;
      void **slot;
      gdb_byte *ptr = info_ptr;

      offset = ptr - dwarf2_per_objfile->types.buffer;

      /* We need to read the type's signature in order to build the hash
         table, but we don't need to read anything else just yet.  */

      /* Sanity check to ensure entire cu is present.  */
      length = read_initial_length (objfile->obfd, ptr, &initial_length_size);
      if (ptr + length + initial_length_size
          > dwarf2_per_objfile->types.buffer + dwarf2_per_objfile->types.size)
        {
          complaint (&symfile_complaints,
                     _("debug type entry runs off end of `.debug_types' section, ignored"));
          break;
        }

      offset_size = initial_length_size == 4 ? 4 : 8;
      ptr += initial_length_size;
      version = bfd_get_16 (objfile->obfd, ptr);
      ptr += 2;
      ptr += offset_size; /* abbrev offset */
      ptr += 1; /* address size */
      signature = bfd_get_64 (objfile->obfd, ptr);
      ptr += 8;
      type_offset = read_offset_1 (objfile->obfd, ptr, offset_size);

      type_sig = obstack_alloc (&objfile->objfile_obstack, sizeof (*type_sig));
      memset (type_sig, 0, sizeof (*type_sig));
      type_sig->signature = signature;
      type_sig->offset = offset;
      type_sig->type_offset = type_offset;

      slot = htab_find_slot (types_htab, type_sig, INSERT);
      gdb_assert (slot != NULL);
      *slot = type_sig;

      if (dwarf2_die_debug)
        fprintf_unfiltered (gdb_stdlog, "  offset 0x%x, signature 0x%s\n",
                            offset, phex (signature, sizeof (signature)));

      info_ptr = info_ptr + initial_length_size + length;
    }

  dwarf2_per_objfile->signatured_types = types_htab;

  return 1;
}

/* Lookup a signature based type.
   Returns NULL if SIG is not present in the table.  */

static struct signatured_type *
lookup_signatured_type (struct objfile *objfile, ULONGEST sig)
{
  struct signatured_type find_entry, *entry;

  if (dwarf2_per_objfile->signatured_types == NULL)
    {
      complaint (&symfile_complaints,
                 _("missing `.debug_types' section for DW_FORM_sig8 die"));
      return 0;
    }

  find_entry.signature = sig;
  entry = htab_find (dwarf2_per_objfile->signatured_types, &find_entry);
  return entry;
}

/* Initialize a die_reader_specs struct from a dwarf2_cu struct.  */

static void
init_cu_die_reader (struct die_reader_specs *reader,
                    struct dwarf2_cu *cu)
{
  reader->abfd = cu->objfile->obfd;
  reader->cu = cu;
  if (cu->per_cu->from_debug_types)
    {
      gdb_assert (dwarf2_per_objfile->types.readin);
      reader->buffer = dwarf2_per_objfile->types.buffer;
    }
  else
    {
      gdb_assert (dwarf2_per_objfile->info.readin);
      reader->buffer = dwarf2_per_objfile->info.buffer;
    }
}

/* Find the base address of the compilation unit for range lists and
   location lists.  It will normally be specified by DW_AT_low_pc.
   In DWARF-3 draft 4, the base address could be overridden by
   DW_AT_entry_pc.  It's been removed, but GCC still uses this for
   compilation units with discontinuous ranges.  */

static void
dwarf2_find_base_address (struct die_info *die, struct dwarf2_cu *cu)
{
  struct attribute *attr;

  cu->base_known = 0;
  cu->base_address = 0;

  attr = dwarf2_attr (die, DW_AT_entry_pc, cu);
  if (attr)
    {
      cu->base_address = DW_ADDR (attr);
      cu->base_known = 1;
    }
  else
    {
      attr = dwarf2_attr (die, DW_AT_low_pc, cu);
      if (attr)
        {
          cu->base_address = DW_ADDR (attr);
          cu->base_known = 1;
        }
    }
}

/* Subroutine of process_type_comp_unit and dwarf2_build_psymtabs_hard
   to combine the common parts.
   Process a compilation unit for a psymtab.
   BUFFER is a pointer to the beginning of the dwarf section buffer,
   either .debug_info or debug_types.
   INFO_PTR is a pointer to the start of the CU.
   Returns a pointer to the next CU.  */

static gdb_byte *
process_psymtab_comp_unit (struct objfile *objfile,
                           struct dwarf2_per_cu_data *this_cu,
                           gdb_byte *buffer, gdb_byte *info_ptr,
                           unsigned int buffer_size)
{
  bfd *abfd = objfile->obfd;
  gdb_byte *beg_of_comp_unit = info_ptr;
  struct die_info *comp_unit_die;
  struct partial_symtab *pst;
  CORE_ADDR baseaddr;
  struct cleanup *back_to_inner;
  struct dwarf2_cu cu;
  int has_children, has_pc_info;
  struct attribute *attr;
  CORE_ADDR best_lowpc = 0, best_highpc = 0;
  struct die_reader_specs reader_specs;

  memset (&cu, 0, sizeof (cu));
  cu.objfile = objfile;
  obstack_init (&cu.comp_unit_obstack);

  back_to_inner = make_cleanup (free_stack_comp_unit, &cu);

  info_ptr = partial_read_comp_unit_head (&cu.header, info_ptr,
                                          buffer, buffer_size,
                                          abfd);

  /* Complete the cu_header.  */
  cu.header.offset = beg_of_comp_unit - buffer;
  cu.header.first_die_offset = info_ptr - beg_of_comp_unit;

  cu.list_in_scope = &file_symbols;

  /* If this compilation unit was already read in, free the
     cached copy in order to read it in again.  This is
     necessary because we skipped some symbols when we first
     read in the compilation unit (see load_partial_dies).
     This problem could be avoided, but the benefit is
     unclear.  */
  if (this_cu->cu != NULL)
    free_one_cached_comp_unit (this_cu->cu);

  /* Note that this is a pointer to our stack frame, being
     added to a global data structure.  It will be cleaned up
     in free_stack_comp_unit when we finish with this
     compilation unit.  */
  this_cu->cu = &cu;
  cu.per_cu = this_cu;

  /* Read the abbrevs for this compilation unit into a table.  */
  dwarf2_read_abbrevs (abfd, &cu);
  make_cleanup (dwarf2_free_abbrev_table, &cu);

  /* Read the compilation unit die.  */
  if (this_cu->from_debug_types)
    info_ptr += 8 /*signature*/ + cu.header.offset_size;
  init_cu_die_reader (&reader_specs, &cu);
  info_ptr = read_full_die (&reader_specs, &comp_unit_die, info_ptr,
                            &has_children);

  if (this_cu->from_debug_types)
    {
      /* offset,length haven't been set yet for type units.  */
      this_cu->offset = cu.header.offset;
      this_cu->length = cu.header.length + cu.header.initial_length_size;
    }
  else if (comp_unit_die->tag == DW_TAG_partial_unit)
    {
      info_ptr = (beg_of_comp_unit + cu.header.length
                  + cu.header.initial_length_size);
      do_cleanups (back_to_inner);
      return info_ptr;
    }

  /* Set the language we're debugging.  */
  attr = dwarf2_attr (comp_unit_die, DW_AT_language, &cu);
  if (attr)
    set_cu_language (DW_UNSND (attr), &cu);
  else
    set_cu_language (language_minimal, &cu);

  /* Allocate a new partial symbol table structure.  */
  attr = dwarf2_attr (comp_unit_die, DW_AT_name, &cu);
  pst = start_psymtab_common (objfile, objfile->section_offsets,
                              (attr != NULL) ? DW_STRING (attr) : "",
                              /* TEXTLOW and TEXTHIGH are set below.  */
                              0,
                              objfile->global_psymbols.next,
                              objfile->static_psymbols.next);

  attr = dwarf2_attr (comp_unit_die, DW_AT_comp_dir, &cu);
  if (attr != NULL)
    pst->dirname = DW_STRING (attr);

  pst->read_symtab_private = this_cu;

  baseaddr = ANOFFSET (objfile->section_offsets, SECT_OFF_TEXT (objfile));

  /* Store the function that reads in the rest of the symbol table */
  pst->read_symtab = dwarf2_psymtab_to_symtab;

  this_cu->v.psymtab = pst;

  dwarf2_find_base_address (comp_unit_die, &cu);

  /* Possibly set the default values of LOWPC and HIGHPC from
     `DW_AT_ranges'.  */
  has_pc_info = dwarf2_get_pc_bounds (comp_unit_die, &best_lowpc,
                                      &best_highpc, &cu, pst);
  if (has_pc_info == 1 && best_lowpc < best_highpc)
    /* Store the contiguous range if it is not empty; it can be empty for
       CUs with no code.  */
    addrmap_set_empty (objfile->psymtabs_addrmap,
                       best_lowpc + baseaddr,
                       best_highpc + baseaddr - 1, pst);

  /* Check if comp unit has_children.
     If so, read the rest of the partial symbols from this comp unit.
     If not, there's no more debug_info for this comp unit. */
  if (has_children)
    {
      struct partial_die_info *first_die;
      CORE_ADDR lowpc, highpc;

      lowpc = ((CORE_ADDR) -1);
      highpc = ((CORE_ADDR) 0);

      first_die = load_partial_dies (abfd, buffer, info_ptr, 1, &cu);

      scan_partial_symbols (first_die, &lowpc, &highpc,
                            ! has_pc_info, &cu);

      /* If we didn't find a lowpc, set it to highpc to avoid
         complaints from `maint check'.  */
      if (lowpc == ((CORE_ADDR) -1))
        lowpc = highpc;

      /* If the compilation unit didn't have an explicit address range,
         then use the information extracted from its child dies.  */
      if (! has_pc_info)
        {
          best_lowpc = lowpc;
          best_highpc = highpc;
        }
    }
  pst->textlow = best_lowpc + baseaddr;
  pst->texthigh = best_highpc + baseaddr;

  pst->n_global_syms = objfile->global_psymbols.next -
    (objfile->global_psymbols.list + pst->globals_offset);
  pst->n_static_syms = objfile->static_psymbols.next -
    (objfile->static_psymbols.list + pst->statics_offset);
  sort_pst_symbols (pst);

  info_ptr = (beg_of_comp_unit + cu.header.length
              + cu.header.initial_length_size);

  if (this_cu->from_debug_types)
    {
      /* It's not clear we want to do anything with stmt lists here.
         Waiting to see what gcc ultimately does.  */
    }
  else
    {
      /* Get the list of files included in the current compilation unit,
         and build a psymtab for each of them.  */
      dwarf2_build_include_psymtabs (&cu, comp_unit_die, pst);
    }

  do_cleanups (back_to_inner);

  return info_ptr;
}

/* Traversal function for htab_traverse_noresize.
   Process one .debug_types comp-unit.  */

static int
process_type_comp_unit (void **slot, void *info)
{
  struct signatured_type *entry = (struct signatured_type *) *slot;
  struct objfile *objfile = (struct objfile *) info;
  struct dwarf2_per_cu_data *this_cu;

  this_cu = &entry->per_cu;
  this_cu->from_debug_types = 1;

  gdb_assert (dwarf2_per_objfile->types.readin);
  process_psymtab_comp_unit (objfile, this_cu,
                             dwarf2_per_objfile->types.buffer,
                             dwarf2_per_objfile->types.buffer + entry->offset,
                             dwarf2_per_objfile->types.size);

  return 1;
}

/* Subroutine of dwarf2_build_psymtabs_hard to simplify it.
   Build partial symbol tables for the .debug_types comp-units.  */

static void
build_type_psymtabs (struct objfile *objfile)
{
  if (! create_debug_types_hash_table (objfile))
    return;

  htab_traverse_noresize (dwarf2_per_objfile->signatured_types,
                          process_type_comp_unit, objfile);
}

/* A cleanup function that clears objfile's psymtabs_addrmap field.  */

static void
psymtabs_addrmap_cleanup (void *o)
{
  struct objfile *objfile = o;

  objfile->psymtabs_addrmap = NULL;
}

/* Build the partial symbol table by doing a quick pass through the
   .debug_info and .debug_abbrev sections.  */

static void
dwarf2_build_psymtabs_hard (struct objfile *objfile)
{
  gdb_byte *info_ptr;
  struct cleanup *back_to, *addrmap_cleanup;
  struct obstack temp_obstack;

  dwarf2_read_section (objfile, &dwarf2_per_objfile->info);
  info_ptr = dwarf2_per_objfile->info.buffer;

  /* Any cached compilation units will be linked by the per-objfile
     read_in_chain.  Make sure to free them when we're done.  */
  back_to = make_cleanup (free_cached_comp_units, NULL);

  build_type_psymtabs (objfile);

  create_all_comp_units (objfile);

  /* Create a temporary address map on a temporary obstack.  We later
     copy this to the final obstack.  */
  obstack_init (&temp_obstack);
  make_cleanup_obstack_free (&temp_obstack);
  objfile->psymtabs_addrmap = addrmap_create_mutable (&temp_obstack);
  addrmap_cleanup = make_cleanup (psymtabs_addrmap_cleanup, objfile);

  /* Since the objects we're extracting from .debug_info vary in
     length, only the individual functions to extract them (like
     read_comp_unit_head and load_partial_die) can really know whether
     the buffer is large enough to hold another complete object.

     At the moment, they don't actually check that.  If .debug_info
     holds just one extra byte after the last compilation unit's dies,
     then read_comp_unit_head will happily read off the end of the
     buffer.  read_partial_die is similarly casual.  Those functions
     should be fixed.

     For this loop condition, simply checking whether there's any data
     left at all should be sufficient.  */

  while (info_ptr < (dwarf2_per_objfile->info.buffer
                     + dwarf2_per_objfile->info.size))
    {
      struct dwarf2_per_cu_data *this_cu;

      this_cu = dwarf2_find_comp_unit (info_ptr - dwarf2_per_objfile->info.buffer,
                                       objfile);

      info_ptr = process_psymtab_comp_unit (objfile, this_cu,
                                            dwarf2_per_objfile->info.buffer,
                                            info_ptr,
                                            dwarf2_per_objfile->info.size);
    }

  objfile->psymtabs_addrmap = addrmap_create_fixed (objfile->psymtabs_addrmap,
                                                    &objfile->objfile_obstack);
  discard_cleanups (addrmap_cleanup);

  do_cleanups (back_to);
}

/* Load the partial DIEs for a secondary CU into memory.  */

static void
load_partial_comp_unit (struct dwarf2_per_cu_data *this_cu,
                        struct objfile *objfile)
{
  bfd *abfd = objfile->obfd;
  gdb_byte *info_ptr, *beg_of_comp_unit;
  struct die_info *comp_unit_die;
  struct dwarf2_cu *cu;
  struct cleanup *back_to;
  struct attribute *attr;
  int has_children;
  struct die_reader_specs reader_specs;

  gdb_assert (! this_cu->from_debug_types);

  gdb_assert (dwarf2_per_objfile->info.readin);
  info_ptr = dwarf2_per_objfile->info.buffer + this_cu->offset;
  beg_of_comp_unit = info_ptr;

  cu = alloc_one_comp_unit (objfile);

  /* ??? Missing cleanup for CU?  */

  /* Link this compilation unit into the compilation unit tree.  */
  this_cu->cu = cu;
  cu->per_cu = this_cu;
  cu->type_hash = this_cu->type_hash;

  info_ptr = partial_read_comp_unit_head (&cu->header, info_ptr,
                                          dwarf2_per_objfile->info.buffer,
                                          dwarf2_per_objfile->info.size,
                                          abfd);

  /* Complete the cu_header.  */
  cu->header.offset = this_cu->offset;
  cu->header.first_die_offset = info_ptr - beg_of_comp_unit;

  /* Read the abbrevs for this compilation unit into a table.  */
  dwarf2_read_abbrevs (abfd, cu);
  back_to = make_cleanup (dwarf2_free_abbrev_table, cu);

  /* Read the compilation unit die.  */
  init_cu_die_reader (&reader_specs, cu);
  info_ptr = read_full_die (&reader_specs, &comp_unit_die, info_ptr,
                            &has_children);

  /* Set the language we're debugging.  */
  attr = dwarf2_attr (comp_unit_die, DW_AT_language, cu);
  if (attr)
    set_cu_language (DW_UNSND (attr), cu);
  else
    set_cu_language (language_minimal, cu);

  /* Check if comp unit has_children.
     If so, read the rest of the partial symbols from this comp unit.
     If not, there's no more debug_info for this comp unit. */
  if (has_children)
    load_partial_dies (abfd, dwarf2_per_objfile->info.buffer, info_ptr, 0, cu);

  do_cleanups (back_to);
}

/* Create a list of all compilation units in OBJFILE.  We do this only
   if an inter-comp-unit reference is found; presumably if there is one,
   there will be many, and one will occur early in the .debug_info section.
   So there's no point in building this list incrementally.  */

static void
create_all_comp_units (struct objfile *objfile)
{
  int n_allocated;
  int n_comp_units;
  struct dwarf2_per_cu_data **all_comp_units;
  gdb_byte *info_ptr;

  dwarf2_read_section (objfile, &dwarf2_per_objfile->info);
  info_ptr = dwarf2_per_objfile->info.buffer;

  n_comp_units = 0;
  n_allocated = 10;
  all_comp_units = xmalloc (n_allocated
                            * sizeof (struct dwarf2_per_cu_data *));

  while (info_ptr < dwarf2_per_objfile->info.buffer + dwarf2_per_objfile->info.size)
    {
      unsigned int length, initial_length_size;
      struct dwarf2_per_cu_data *this_cu;
      unsigned int offset;

      offset = info_ptr - dwarf2_per_objfile->info.buffer;

      /* Read just enough information to find out where the next
         compilation unit is.  */
      length = read_initial_length (objfile->obfd, info_ptr,
                                    &initial_length_size);

      /* Save the compilation unit for later lookup.  */
      this_cu = obstack_alloc (&objfile->objfile_obstack,
                               sizeof (struct dwarf2_per_cu_data));
      memset (this_cu, 0, sizeof (*this_cu));
      this_cu->offset = offset;
      this_cu->length = length + initial_length_size;
      this_cu->objfile = objfile;

      if (n_comp_units == n_allocated)
        {
          n_allocated *= 2;
          all_comp_units = xrealloc (all_comp_units,
                                     n_allocated
                                     * sizeof (struct dwarf2_per_cu_data *));
        }
      all_comp_units[n_comp_units++] = this_cu;

      info_ptr = info_ptr + this_cu->length;
    }

  dwarf2_per_objfile->all_comp_units
    = obstack_alloc (&objfile->objfile_obstack,
                     n_comp_units * sizeof (struct dwarf2_per_cu_data *));
  memcpy (dwarf2_per_objfile->all_comp_units, all_comp_units,
          n_comp_units * sizeof (struct dwarf2_per_cu_data *));
  xfree (all_comp_units);
  dwarf2_per_objfile->n_comp_units = n_comp_units;
}

/* Process all loaded DIEs for compilation unit CU, starting at
   FIRST_DIE.  The caller should pass NEED_PC == 1 if the compilation
   unit DIE did not have PC info (DW_AT_low_pc and DW_AT_high_pc, or
   DW_AT_ranges).  If NEED_PC is set, then this function will set
   *LOWPC and *HIGHPC to the lowest and highest PC values found in CU
   and record the covered ranges in the addrmap.  */

static void
scan_partial_symbols (struct partial_die_info *first_die, CORE_ADDR *lowpc,
                      CORE_ADDR *highpc, int need_pc, struct dwarf2_cu *cu)
{
  struct partial_die_info *pdi;

  /* Now, march along the PDI's, descending into ones which have
     interesting children but skipping the children of the other ones,
     until we reach the end of the compilation unit.  */

  pdi = first_die;

  while (pdi != NULL)
    {
      fixup_partial_die (pdi, cu);

      /* Anonymous namespaces or modules have no name but have interesting
         children, so we need to look at them.  Ditto for anonymous
         enums.  */

      if (pdi->name != NULL || pdi->tag == DW_TAG_namespace
          || pdi->tag == DW_TAG_module || pdi->tag == DW_TAG_enumeration_type)
        {
          switch (pdi->tag)
            {
            case DW_TAG_subprogram:
              add_partial_subprogram (pdi, lowpc, highpc, need_pc, cu);
              break;
            case DW_TAG_variable:
            case DW_TAG_typedef:
            case DW_TAG_union_type:
              if (!pdi->is_declaration)
                {
                  add_partial_symbol (pdi, cu);
                }
              break;
            case DW_TAG_class_type:
            case DW_TAG_interface_type:
            case DW_TAG_structure_type:
              if (!pdi->is_declaration)
                {
                  add_partial_symbol (pdi, cu);
                }
              break;
            case DW_TAG_enumeration_type:
              if (!pdi->is_declaration)
                add_partial_enumeration (pdi, cu);
              break;
            case DW_TAG_base_type:
            case DW_TAG_subrange_type:
              /* File scope base type definitions are added to the partial
                 symbol table.  */
              add_partial_symbol (pdi, cu);
              break;
            case DW_TAG_namespace:
              add_partial_namespace (pdi, lowpc, highpc, need_pc, cu);
              break;
            case DW_TAG_module:
              add_partial_module (pdi, lowpc, highpc, need_pc, cu);
              break;
            default:
              break;
            }
        }

      /* If the die has a sibling, skip to the sibling.  */

      pdi = pdi->die_sibling;
    }
}

/* Functions used to compute the fully scoped name of a partial DIE.

   Normally, this is simple.  For C++, the parent DIE's fully scoped
   name is concatenated with "::" and the partial DIE's name.  For
   Java, the same thing occurs except that "." is used instead of "::".
   Enumerators are an exception; they use the scope of their parent
   enumeration type, i.e. the name of the enumeration type is not
   prepended to the enumerator.

   There are two complexities.  One is DW_AT_specification; in this
   case "parent" means the parent of the target of the specification,
   instead of the direct parent of the DIE.  The other is compilers
   which do not emit DW_TAG_namespace; in this case we try to guess
   the fully qualified name of structure types from their members'
   linkage names.  This must be done using the DIE's children rather
   than the children of any DW_AT_specification target.  We only need
   to do this for structures at the top level, i.e. if the target of
   any DW_AT_specification (if any; otherwise the DIE itself) does not
   have a parent.  */

/* Compute the scope prefix associated with PDI's parent, in
   compilation unit CU.  The result will be allocated on CU's
   comp_unit_obstack, or a copy of the already allocated PDI->NAME
   field.  NULL is returned if no prefix is necessary.  */
static char *
partial_die_parent_scope (struct partial_die_info *pdi,
                          struct dwarf2_cu *cu)
{
  char *grandparent_scope;
  struct partial_die_info *parent, *real_pdi;

  /* We need to look at our parent DIE; if we have a DW_AT_specification,
     then this means the parent of the specification DIE.  */

  real_pdi = pdi;
  while (real_pdi->has_specification)
    real_pdi = find_partial_die (real_pdi->spec_offset, cu);

  parent = real_pdi->die_parent;
  if (parent == NULL)
    return NULL;

  if (parent->scope_set)
    return parent->scope;

  fixup_partial_die (parent, cu);

  grandparent_scope = partial_die_parent_scope (parent, cu);

  /* GCC 4.0 and 4.1 had a bug (PR c++/28460) where they generated bogus
     DW_TAG_namespace DIEs with a name of "::" for the global namespace.
     Work around this problem here.  */
  if (cu->language == language_cplus
      && parent->tag == DW_TAG_namespace
      && strcmp (parent->name, "::") == 0
      && grandparent_scope == NULL)
    {
      parent->scope = NULL;
      parent->scope_set = 1;
      return NULL;
    }

  if (parent->tag == DW_TAG_namespace
      || parent->tag == DW_TAG_module
      || parent->tag == DW_TAG_structure_type
      || parent->tag == DW_TAG_class_type
      || parent->tag == DW_TAG_interface_type
      || parent->tag == DW_TAG_union_type
      || parent->tag == DW_TAG_enumeration_type)
    {
      if (grandparent_scope == NULL)
        parent->scope = parent->name;
      else
        parent->scope = typename_concat (&cu->comp_unit_obstack, grandparent_scope,
                                         parent->name, 0, cu);
    }
  else if (parent->tag == DW_TAG_enumerator)
    /* Enumerators should not get the name of the enumeration as a prefix.  */
    parent->scope = grandparent_scope;
  else
    {
      /* FIXME drow/2004-04-01: What should we be doing with
         function-local names?  For partial symbols, we should probably be
         ignoring them.  */
      complaint (&symfile_complaints,
                 _("unhandled containing DIE tag %d for DIE at %d"),
                 parent->tag, pdi->offset);
      parent->scope = grandparent_scope;
    }

  parent->scope_set = 1;
  return parent->scope;
}

/* Return the fully scoped name associated with PDI, from compilation unit
   CU.  The result will be allocated with malloc.  */
static char *
partial_die_full_name (struct partial_die_info *pdi,
                       struct dwarf2_cu *cu)
{
  char *parent_scope;

  parent_scope = partial_die_parent_scope (pdi, cu);
  if (parent_scope == NULL)
    return NULL;
  else
    return typename_concat (NULL, parent_scope, pdi->name, 0, cu);
}

static void
add_partial_symbol (struct partial_die_info *pdi, struct dwarf2_cu *cu)
{
  struct objfile *objfile = cu->objfile;
  CORE_ADDR addr = 0;
  char *actual_name = NULL;
  const struct partial_symbol *psym = NULL;
  CORE_ADDR baseaddr;
  int built_actual_name = 0;

  baseaddr = ANOFFSET (objfile->section_offsets, SECT_OFF_TEXT (objfile));

  actual_name = partial_die_full_name (pdi, cu);
  if (actual_name)
    built_actual_name = 1;

  if (actual_name == NULL)
    actual_name = pdi->name;

  switch (pdi->tag)
    {
    case DW_TAG_subprogram:
      if (pdi->is_external || cu->language == language_ada)
        {
          /* brobecker/2007-12-26: Normally, only "external" DIEs are part
             of the global scope.  But in Ada, we want to be able to access
             nested procedures globally.  So all Ada subprograms are stored
             in the global scope.  */
          /*prim_record_minimal_symbol (actual_name, pdi->lowpc + baseaddr,
             mst_text, objfile); */
          psym = add_psymbol_to_list (actual_name, strlen (actual_name),
                                      built_actual_name,
                                      VAR_DOMAIN, LOC_BLOCK,
                                      &objfile->global_psymbols,
                                      0, pdi->lowpc + baseaddr,
                                      cu->language, objfile);
        }
      else
        {
          /*prim_record_minimal_symbol (actual_name, pdi->lowpc + baseaddr,
             mst_file_text, objfile); */
          psym = add_psymbol_to_list (actual_name, strlen (actual_name),
                                      built_actual_name,
                                      VAR_DOMAIN, LOC_BLOCK,
                                      &objfile->static_psymbols,
                                      0, pdi->lowpc + baseaddr,
                                      cu->language, objfile);
        }
      break;
    case DW_TAG_variable:
      if (pdi->is_external)
        {
          /* Global Variable.
             Don't enter into the minimal symbol tables as there is
             a minimal symbol table entry from the ELF symbols already.
             Enter into partial symbol table if it has a location
             descriptor or a type.
             If the location descriptor is missing, new_symbol will create
             a LOC_UNRESOLVED symbol, the address of the variable will then
             be determined from the minimal symbol table whenever the variable
             is referenced.
             The address for the partial symbol table entry is not
             used by GDB, but it comes in handy for debugging partial symbol
             table building.  */

          if (pdi->locdesc)
            addr = decode_locdesc (pdi->locdesc, cu);
          if (pdi->locdesc || pdi->has_type)
            psym = add_psymbol_to_list (actual_name, strlen (actual_name),
                                        built_actual_name,
                                        VAR_DOMAIN, LOC_STATIC,
                                        &objfile->global_psymbols,
                                        0, addr + baseaddr,
                                        cu->language, objfile);
        }
      else
        {
          /* Static Variable. Skip symbols without location descriptors.  */
          if (pdi->locdesc == NULL)
            {
              if (built_actual_name)
                xfree (actual_name);
              return;
            }
          addr = decode_locdesc (pdi->locdesc, cu);
          /*prim_record_minimal_symbol (actual_name, addr + baseaddr,
             mst_file_data, objfile); */
          psym = add_psymbol_to_list (actual_name, strlen (actual_name),
                                      built_actual_name,
                                      VAR_DOMAIN, LOC_STATIC,
                                      &objfile->static_psymbols,
                                      0, addr + baseaddr,
                                      cu->language, objfile);
        }
      break;
    case DW_TAG_typedef:
    case DW_TAG_base_type:
    case DW_TAG_subrange_type:
      add_psymbol_to_list (actual_name, strlen (actual_name),
                           built_actual_name,
                           VAR_DOMAIN, LOC_TYPEDEF,
                           &objfile->static_psymbols,
                           0, (CORE_ADDR) 0, cu->language, objfile);
      break;
    case DW_TAG_namespace:
      add_psymbol_to_list (actual_name, strlen (actual_name),
                           built_actual_name,
                           VAR_DOMAIN, LOC_TYPEDEF,
                           &objfile->global_psymbols,
                           0, (CORE_ADDR) 0, cu->language, objfile);
      break;
    case DW_TAG_class_type:
    case DW_TAG_interface_type:
    case DW_TAG_structure_type:
    case DW_TAG_union_type:
    case DW_TAG_enumeration_type:
      /* Skip external references.  The DWARF standard says in the section
         about "Structure, Union, and Class Type Entries": "An incomplete
         structure, union or class type is represented by a structure,
         union or class entry that does not have a byte size attribute
         and that has a DW_AT_declaration attribute."  */
      if (!pdi->has_byte_size && pdi->is_declaration)
        {
          if (built_actual_name)
            xfree (actual_name);
          return;
        }

      /* NOTE: carlton/2003-10-07: See comment in new_symbol about
         static vs. global.  */
      add_psymbol_to_list (actual_name, strlen (actual_name),
                           built_actual_name,
                           STRUCT_DOMAIN, LOC_TYPEDEF,
                           (cu->language == language_cplus
                            || cu->language == language_java)
                           ? &objfile->global_psymbols
                           : &objfile->static_psymbols,
                           0, (CORE_ADDR) 0, cu->language, objfile);

      break;
    case DW_TAG_enumerator:
      add_psymbol_to_list (actual_name, strlen (actual_name),
                           built_actual_name,
                           VAR_DOMAIN, LOC_CONST,
                           (cu->language == language_cplus
                            || cu->language == language_java)
                           ? &objfile->global_psymbols
                           : &objfile->static_psymbols,
                           0, (CORE_ADDR) 0, cu->language, objfile);
      break;
    default:
      break;
    }

  if (built_actual_name)
    xfree (actual_name);
}

/* Read a partial die corresponding to a namespace; also, add a symbol
   corresponding to that namespace to the symbol table.  NAMESPACE is
   the name of the enclosing namespace.  */

static void
add_partial_namespace (struct partial_die_info *pdi,
                       CORE_ADDR *lowpc, CORE_ADDR *highpc,
                       int need_pc, struct dwarf2_cu *cu)
{
  /* Add a symbol for the namespace.  */

  add_partial_symbol (pdi, cu);

  /* Now scan partial symbols in that namespace.  */

  if (pdi->has_children)
    scan_partial_symbols (pdi->die_child, lowpc, highpc, need_pc, cu);
}

/* Read a partial die corresponding to a Fortran module.  */

static void
add_partial_module (struct partial_die_info *pdi, CORE_ADDR *lowpc,
                    CORE_ADDR *highpc, int need_pc, struct dwarf2_cu *cu)
{
  /* Now scan partial symbols in that module.  */

  if (pdi->has_children)
    scan_partial_symbols (pdi->die_child, lowpc, highpc, need_pc, cu);
}

/* Read a partial die corresponding to a subprogram and create a partial
   symbol for that subprogram.  When the CU language allows it, this
   routine also defines a partial symbol for each nested subprogram
   that this subprogram contains.

   DIE my also be a lexical block, in which case we simply search
   recursively for suprograms defined inside that lexical block.
   Again, this is only performed when the CU language allows this
   type of definitions.  */

static void
add_partial_subprogram (struct partial_die_info *pdi,
                        CORE_ADDR *lowpc, CORE_ADDR *highpc,
                        int need_pc, struct dwarf2_cu *cu)
{
  if (pdi->tag == DW_TAG_subprogram)
    {
      if (pdi->has_pc_info)
        {
          if (pdi->lowpc < *lowpc)
            *lowpc = pdi->lowpc;
          if (pdi->highpc > *highpc)
            *highpc = pdi->highpc;
          if (need_pc)
            {
              CORE_ADDR baseaddr;
              struct objfile *objfile = cu->objfile;

              baseaddr = ANOFFSET (objfile->section_offsets,
                                   SECT_OFF_TEXT (objfile));
              addrmap_set_empty (objfile->psymtabs_addrmap,
                                 pdi->lowpc + baseaddr,
                                 pdi->highpc - 1 + baseaddr,
                                 cu->per_cu->v.psymtab);
            }
          if (!pdi->is_declaration)
            /* Ignore subprogram DIEs that do not have a name, they are
               illegal.  Do not emit a complaint at this point, we will
               do so when we convert this psymtab into a symtab.  */
            if (pdi->name)
              add_partial_symbol (pdi, cu);
        }
    }

  if (! pdi->has_children)
    return;

  if (cu->language == language_ada)
    {
      pdi = pdi->die_child;
      while (pdi != NULL)
        {
          fixup_partial_die (pdi, cu);
          if (pdi->tag == DW_TAG_subprogram
              || pdi->tag == DW_TAG_lexical_block)
            add_partial_subprogram (pdi, lowpc, highpc, need_pc, cu);
          pdi = pdi->die_sibling;
        }
    }
}

/* See if we can figure out if the class lives in a namespace.  We do
   this by looking for a member function; its demangled name will
   contain namespace info, if there is any.  */

static void
guess_structure_name (struct partial_die_info *struct_pdi,
                      struct dwarf2_cu *cu)
{
  if ((cu->language == language_cplus
       || cu->language == language_java)
      && cu->has_namespace_info == 0
      && struct_pdi->has_children)
    {
      /* NOTE: carlton/2003-10-07: Getting the info this way changes
         what template types look like, because the demangler
         frequently doesn't give the same name as the debug info.  We
         could fix this by only using the demangled name to get the
         prefix (but see comment in read_structure_type).  */

      struct partial_die_info *real_pdi;

      /* If this DIE (this DIE's specification, if any) has a parent, then
         we should not do this.  We'll prepend the parent's fully qualified
         name when we create the partial symbol.  */

      real_pdi = struct_pdi;
      while (real_pdi->has_specification)
        real_pdi = find_partial_die (real_pdi->spec_offset, cu);

      if (real_pdi->die_parent != NULL)
        return;
    }
}

/* Read a partial die corresponding to an enumeration type.  */

static void
add_partial_enumeration (struct partial_die_info *enum_pdi,
                         struct dwarf2_cu *cu)
{
  struct partial_die_info *pdi;

  if (enum_pdi->name != NULL)
    add_partial_symbol (enum_pdi, cu);

  pdi = enum_pdi->die_child;
  while (pdi)
    {
      if (pdi->tag != DW_TAG_enumerator || pdi->name == NULL)
        complaint (&symfile_complaints, _("malformed enumerator DIE ignored"));
      else
        add_partial_symbol (pdi, cu);
      pdi = pdi->die_sibling;
    }
}

/* Read the initial uleb128 in the die at INFO_PTR in compilation unit CU.
   Return the corresponding abbrev, or NULL if the number is zero (indicating
   an empty DIE).  In either case *BYTES_READ will be set to the length of
   the initial number.  */

static struct abbrev_info *
peek_die_abbrev (gdb_byte *info_ptr, unsigned int *bytes_read,
                 struct dwarf2_cu *cu)
{
  bfd *abfd = cu->objfile->obfd;
  unsigned int abbrev_number;
  struct abbrev_info *abbrev;

  abbrev_number = read_unsigned_leb128 (abfd, info_ptr, bytes_read);

  if (abbrev_number == 0)
    return NULL;

  abbrev = dwarf2_lookup_abbrev (abbrev_number, cu);
  if (!abbrev)
    {
      error (_("Dwarf Error: Could not find abbrev number %d [in module %s]"), abbrev_number,
                      bfd_get_filename (abfd));
    }

  return abbrev;
}

/* Scan the debug information for CU starting at INFO_PTR in buffer BUFFER.
   Returns a pointer to the end of a series of DIEs, terminated by an empty
   DIE.  Any children of the skipped DIEs will also be skipped.  */

static gdb_byte *
skip_children (gdb_byte *buffer, gdb_byte *info_ptr, struct dwarf2_cu *cu)
{
  struct abbrev_info *abbrev;
  unsigned int bytes_read;

  while (1)
    {
      abbrev = peek_die_abbrev (info_ptr, &bytes_read, cu);
      if (abbrev == NULL)
        return info_ptr + bytes_read;
      else
        info_ptr = skip_one_die (buffer, info_ptr + bytes_read, abbrev, cu);
    }
}

/* Scan the debug information for CU starting at INFO_PTR in buffer BUFFER.
   INFO_PTR should point just after the initial uleb128 of a DIE, and the
   abbrev corresponding to that skipped uleb128 should be passed in
   ABBREV.  Returns a pointer to this DIE's sibling, skipping any
   children.  */

static gdb_byte *
skip_one_die (gdb_byte *buffer, gdb_byte *info_ptr,
              struct abbrev_info *abbrev, struct dwarf2_cu *cu)
{
  unsigned int bytes_read;
  struct attribute attr;
  bfd *abfd = cu->objfile->obfd;
  unsigned int form, i;

  for (i = 0; i < abbrev->num_attrs; i++)
    {
      /* The only abbrev we care about is DW_AT_sibling.  */
      if (abbrev->attrs[i].name == DW_AT_sibling)
        {
          read_attribute (&attr, &abbrev->attrs[i],
                          abfd, info_ptr, cu);
          if (attr.form == DW_FORM_ref_addr)
            complaint (&symfile_complaints, _("ignoring absolute DW_AT_sibling"));
          else
            return buffer + dwarf2_get_ref_die_offset (&attr);
        }

      /* If it isn't DW_AT_sibling, skip this attribute.  */
      form = abbrev->attrs[i].form;
    skip_attribute:
      switch (form)
        {
        case DW_FORM_ref_addr:
          /* In DWARF 2, DW_FORM_ref_addr is address sized; in DWARF 3
             and later it is offset sized.  */
          if (cu->header.version == 2)
            info_ptr += cu->header.addr_size;
          else
            info_ptr += cu->header.offset_size;
          break;
        case DW_FORM_addr:
          info_ptr += cu->header.addr_size;
          break;
        case DW_FORM_data1:
        case DW_FORM_ref1:
        case DW_FORM_flag:
          info_ptr += 1;
          break;
        case DW_FORM_flag_present:
          break;
        case DW_FORM_data2:
        case DW_FORM_ref2:
          info_ptr += 2;
          break;
        case DW_FORM_data4:
        case DW_FORM_ref4:
          info_ptr += 4;
          break;
        case DW_FORM_data8:
        case DW_FORM_ref8:
        case DW_FORM_sig8:
          info_ptr += 8;
          break;
        case DW_FORM_string:
          read_string (abfd, info_ptr, &bytes_read);
          info_ptr += bytes_read;
          break;
        case DW_FORM_sec_offset:
        case DW_FORM_strp:
          info_ptr += cu->header.offset_size;
          break;
        case DW_FORM_exprloc:
        case DW_FORM_block:
          info_ptr += read_unsigned_leb128 (abfd, info_ptr, &bytes_read);
          info_ptr += bytes_read;
          break;
        case DW_FORM_block1:
          info_ptr += 1 + read_1_byte (abfd, info_ptr);
          break;
        case DW_FORM_block2:
          info_ptr += 2 + read_2_bytes (abfd, info_ptr);
          break;
        case DW_FORM_block4:
          info_ptr += 4 + read_4_bytes (abfd, info_ptr);
          break;
        case DW_FORM_sdata:
        case DW_FORM_udata:
        case DW_FORM_ref_udata:
          info_ptr = skip_leb128 (abfd, info_ptr);
          break;
        case DW_FORM_indirect:
          form = read_unsigned_leb128 (abfd, info_ptr, &bytes_read);
          info_ptr += bytes_read;
          /* We need to continue parsing from here, so just go back to
             the top.  */
          goto skip_attribute;

        default:
          error (_("Dwarf Error: Cannot handle %s in DWARF reader [in module %s]"),
                 dwarf_form_name (form),
                 bfd_get_filename (abfd));
        }
    }

  if (abbrev->has_children)
    return skip_children (buffer, info_ptr, cu);
  else
    return info_ptr;
}

/* Locate ORIG_PDI's sibling.
   INFO_PTR should point to the start of the next DIE after ORIG_PDI
   in BUFFER.  */

static gdb_byte *
locate_pdi_sibling (struct partial_die_info *orig_pdi,
                    gdb_byte *buffer, gdb_byte *info_ptr,
                    bfd *abfd, struct dwarf2_cu *cu)
{
  /* Do we know the sibling already?  */

  if (orig_pdi->sibling)
    return orig_pdi->sibling;

  /* Are there any children to deal with?  */

  if (!orig_pdi->has_children)
    return info_ptr;

  /* Skip the children the long way.  */

  return skip_children (buffer, info_ptr, cu);
}

/* Expand this partial symbol table into a full symbol table.  */

static void
dwarf2_psymtab_to_symtab (struct partial_symtab *pst)
{
  if (pst != NULL)
    {
      if (pst->readin)
        {
          warning (_("bug: psymtab for %s is already read in."), pst->filename);
        }
      else
        {
          if (info_verbose)
            {
              printf_filtered (_("Reading in symbols for %s..."), pst->filename);
              gdb_flush (gdb_stdout);
            }

          /* Restore our global data.  */
          dwarf2_per_objfile = objfile_data (pst->objfile,
                                             dwarf2_objfile_data_key);

          /* If this psymtab is constructed from a debug-only objfile, the
             has_section_at_zero flag will not necessarily be correct.  We
             can get the correct value for this flag by looking at the data
             associated with the (presumably stripped) associated objfile.  */
          if (pst->objfile->separate_debug_objfile_backlink)
            {
              struct dwarf2_per_objfile *dpo_backlink
                = objfile_data (pst->objfile->separate_debug_objfile_backlink,
                                dwarf2_objfile_data_key);

              dwarf2_per_objfile->has_section_at_zero
                = dpo_backlink->has_section_at_zero;
            }

          psymtab_to_symtab_1 (pst);

          /* Finish up the debug error message.  */
          if (info_verbose)
            printf_filtered (_("done.\n"));
        }
    }
}

/* Add PER_CU to the queue.  */

static void
queue_comp_unit (struct dwarf2_per_cu_data *per_cu, struct objfile *objfile)
{
  struct dwarf2_queue_item *item;

  per_cu->queued = 1;
  item = xmalloc (sizeof (*item));
  item->per_cu = per_cu;
  item->next = NULL;

  if (dwarf2_queue == NULL)
    dwarf2_queue = item;
  else
    dwarf2_queue_tail->next = item;

  dwarf2_queue_tail = item;
}

/* Process the queue.  */

static void
process_queue (struct objfile *objfile)
{
  struct dwarf2_queue_item *item, *next_item;

  /* The queue starts out with one item, but following a DIE reference
     may load a new CU, adding it to the end of the queue.  */
  for (item = dwarf2_queue; item != NULL; dwarf2_queue = item = next_item)
    {
      if (dwarf2_per_objfile->using_index
          ? !item->per_cu->v.quick->symtab
          : (item->per_cu->v.psymtab && !item->per_cu->v.psymtab->readin))
        process_full_comp_unit (item->per_cu);

      item->per_cu->queued = 0;
      next_item = item->next;
      xfree (item);
    }

  dwarf2_queue_tail = NULL;
}

/* Free all allocated queue entries.  This function only releases anything if
   an error was thrown; if the queue was processed then it would have been
   freed as we went along.  */

static void
dwarf2_release_queue (void *dummy)
{
  struct dwarf2_queue_item *item, *last;

  item = dwarf2_queue;
  while (item)
    {
      /* Anything still marked queued is likely to be in an
         inconsistent state, so discard it.  */
      if (item->per_cu->queued)
        {
          if (item->per_cu->cu != NULL)
            free_one_cached_comp_unit (item->per_cu->cu);
          item->per_cu->queued = 0;
        }

      last = item;
      item = item->next;
      xfree (last);
    }

  dwarf2_queue = dwarf2_queue_tail = NULL;
}

/* Read in full symbols for PST, and anything it depends on.  */

static void
psymtab_to_symtab_1 (struct partial_symtab *pst)
{
  struct dwarf2_per_cu_data *per_cu;
  struct cleanup *back_to;
  int i;

  for (i = 0; i < pst->number_of_dependencies; i++)
    if (!pst->dependencies[i]->readin)
      {
        /* Inform about additional files that need to be read in.  */
        if (info_verbose)
          {
            /* FIXME: i18n: Need to make this a single string.  */
            fputs_filtered (" ", gdb_stdout);
            wrap_here ("");
            fputs_filtered ("and ", gdb_stdout);
            wrap_here ("");
            printf_filtered ("%s...", pst->dependencies[i]->filename);
            wrap_here ("");     /* Flush output */
            gdb_flush (gdb_stdout);
          }
        psymtab_to_symtab_1 (pst->dependencies[i]);
      }

  per_cu = pst->read_symtab_private;

  if (per_cu == NULL)
    {
      /* It's an include file, no symbols to read for it.
         Everything is in the parent symtab.  */
      pst->readin = 1;
      return;
    }

  dw2_do_instantiate_symtab (pst->objfile, per_cu);
}

/* Load the DIEs associated with PER_CU into memory.  */

static void
load_full_comp_unit (struct dwarf2_per_cu_data *per_cu, struct objfile *objfile)
{
  bfd *abfd = objfile->obfd;
  struct dwarf2_cu *cu;
  unsigned int offset;
  gdb_byte *info_ptr, *beg_of_comp_unit;
  struct cleanup *back_to, *free_cu_cleanup;
  struct attribute *attr;

  gdb_assert (! per_cu->from_debug_types);

  /* Set local variables from the partial symbol table info.  */
  offset = per_cu->offset;

  dwarf2_read_section (objfile, &dwarf2_per_objfile->info);
  info_ptr = dwarf2_per_objfile->info.buffer + offset;
  beg_of_comp_unit = info_ptr;

  cu = alloc_one_comp_unit (objfile);

  /* If an error occurs while loading, release our storage.  */
  free_cu_cleanup = make_cleanup (free_one_comp_unit, cu);

  /* Read in the comp_unit header.  */
  info_ptr = read_comp_unit_head (&cu->header, info_ptr, abfd);

  /* Complete the cu_header.  */
  cu->header.offset = offset;
  cu->header.first_die_offset = info_ptr - beg_of_comp_unit;

  /* Read the abbrevs for this compilation unit.  */
  dwarf2_read_abbrevs (abfd, cu);
  back_to = make_cleanup (dwarf2_free_abbrev_table, cu);

  /* Link this compilation unit into the compilation unit tree.  */
  per_cu->cu = cu;
  cu->per_cu = per_cu;
  cu->type_hash = per_cu->type_hash;

  cu->dies = read_comp_unit (info_ptr, cu);

  /* We try not to read any attributes in this function, because not
     all objfiles needed for references have been loaded yet, and symbol
     table processing isn't initialized.  But we have to set the CU language,
     or we won't be able to build types correctly.  */
  attr = dwarf2_attr (cu->dies, DW_AT_language, cu);
  if (attr)
    set_cu_language (DW_UNSND (attr), cu);
  else
    set_cu_language (language_minimal, cu);

  /* Similarly, if we do not read the producer, we can not apply
     producer-specific interpretation.  */
  attr = dwarf2_attr (cu->dies, DW_AT_producer, cu);
  if (attr)
    cu->producer = DW_STRING (attr);

  /* Link this CU into read_in_chain.  */
  per_cu->cu->read_in_chain = dwarf2_per_objfile->read_in_chain;
  dwarf2_per_objfile->read_in_chain = per_cu;

  do_cleanups (back_to);

  /* We've successfully allocated this compilation unit.  Let our caller
     clean it up when finished with it.  */
  discard_cleanups (free_cu_cleanup);
}

/* Generate full symbol information for PST and CU, whose DIEs have
   already been loaded into memory.  */

static void
process_full_comp_unit (struct dwarf2_per_cu_data *per_cu)
{
  struct dwarf2_cu *cu = per_cu->cu;
  struct objfile *objfile = per_cu->objfile;
  CORE_ADDR lowpc, highpc;
  struct symtab *symtab;
  struct cleanup *back_to;
  CORE_ADDR baseaddr;

  baseaddr = ANOFFSET (objfile->section_offsets, SECT_OFF_TEXT (objfile));

  buildsym_init ();
  back_to = make_cleanup (really_free_pendings, NULL);

  cu->list_in_scope = &file_symbols;

  dwarf2_find_base_address (cu->dies, cu);

  /* Do line number decoding in read_file_scope () */
  process_die (cu->dies, cu);

  /* Some compilers don't define a DW_AT_high_pc attribute for the
     compilation unit.  If the DW_AT_high_pc is missing, synthesize
     it, by scanning the DIE's below the compilation unit.  */
  get_scope_pc_bounds (cu->dies, &lowpc, &highpc, cu);

  symtab = end_symtab (highpc + baseaddr, objfile, SECT_OFF_TEXT (objfile));

  /* Set symtab language to language from DW_AT_language.
     If the compilation is from a C file generated by language preprocessors,
     do not set the language if it was already deduced by start_subfile.  */
  if (symtab != NULL
      && !(cu->language == language_c && symtab->language != language_c))
    {
      symtab->language = cu->language;
    }

  if (dwarf2_per_objfile->using_index)
    per_cu->v.quick->symtab = symtab;
  else
    {
      struct partial_symtab *pst = per_cu->v.psymtab;
      pst->symtab = symtab;
      pst->readin = 1;
    }

  do_cleanups (back_to);
}

/* Process a die and its children.  */

static void
process_die (struct die_info *die, struct dwarf2_cu *cu)
{
  switch (die->tag)
    {
    case DW_TAG_padding:
      break;
    case DW_TAG_compile_unit:
      read_file_scope (die, cu);
      break;
    case DW_TAG_type_unit:
      read_type_unit_scope (die, cu);
      break;
    case DW_TAG_subprogram:
    case DW_TAG_inlined_subroutine:
      read_func_scope (die, cu);
      break;
    case DW_TAG_lexical_block:
    case DW_TAG_try_block:
    case DW_TAG_catch_block:
      read_lexical_block_scope (die, cu);
      break;
    case DW_TAG_class_type:
    case DW_TAG_interface_type:
    case DW_TAG_structure_type:
    case DW_TAG_union_type:
      process_structure_scope (die, cu);
      break;
    case DW_TAG_enumeration_type:
      process_enumeration_scope (die, cu);
      break;

    /* These dies have a type, but processing them does not create
       a symbol or recurse to process the children.  Therefore we can
       read them on-demand through read_type_die.  */
    case DW_TAG_subroutine_type:
    case DW_TAG_set_type:
    case DW_TAG_array_type:
    case DW_TAG_pointer_type:
    case DW_TAG_ptr_to_member_type:
    case DW_TAG_reference_type:
    case DW_TAG_string_type:
      break;

    case DW_TAG_base_type:
    case DW_TAG_subrange_type:
    case DW_TAG_typedef:
    case DW_TAG_const_type:
    case DW_TAG_volatile_type:
      /* Add a typedef symbol for the type definition, if it has a
         DW_AT_name.  */
      new_symbol (die, read_type_die (die, cu), cu);
      break;
    case DW_TAG_common_block:
      read_common_block (die, cu);
      break;
    case DW_TAG_common_inclusion:
      break;
    case DW_TAG_namespace:
      processing_has_namespace_info = 1;
      read_namespace (die, cu);
      break;
    case DW_TAG_module:
      processing_has_namespace_info = 1;
      read_module (die, cu);
      break;
    case DW_TAG_imported_declaration:
    case DW_TAG_imported_module:
      processing_has_namespace_info = 1;
      if (die->child != NULL && (die->tag == DW_TAG_imported_declaration
                                 || cu->language != language_fortran))
        complaint (&symfile_complaints, _("Tag '%s' has unexpected children"),
                   dwarf_tag_name (die->tag));
      read_import_statement (die, cu);
      break;
    default:
      new_symbol (die, NULL, cu);
      break;
    }
}

/* A helper function for dwarf2_compute_name which determines whether DIE
   needs to have the name of the scope prepended to the name listed in the
   die.  */

static int
die_needs_namespace (struct die_info *die, struct dwarf2_cu *cu)
{
  struct attribute *attr;

  switch (die->tag)
    {
    case DW_TAG_namespace:
    case DW_TAG_typedef:
    case DW_TAG_class_type:
    case DW_TAG_interface_type:
    case DW_TAG_structure_type:
    case DW_TAG_union_type:
    case DW_TAG_enumeration_type:
    case DW_TAG_enumerator:
    case DW_TAG_subprogram:
    case DW_TAG_member:
      return 1;

    case DW_TAG_variable:
      /* We only need to prefix "globally" visible variables.  These include
         any variable marked with DW_AT_external or any variable that
         lives in a namespace.  [Variables in anonymous namespaces
         require prefixing, but they are not DW_AT_external.]  */

      if (dwarf2_attr (die, DW_AT_specification, cu))
        {
          struct dwarf2_cu *spec_cu = cu;

          return die_needs_namespace (die_specification (die, &spec_cu),
                                      spec_cu);
        }

      attr = dwarf2_attr (die, DW_AT_external, cu);
      if (attr == NULL && die->parent->tag != DW_TAG_namespace
          && die->parent->tag != DW_TAG_module)
        return 0;
      /* A variable in a lexical block of some kind does not need a
         namespace, even though in C++ such variables may be external
         and have a mangled name.  */
      if (die->parent->tag ==  DW_TAG_lexical_block
          || die->parent->tag ==  DW_TAG_try_block
          || die->parent->tag ==  DW_TAG_catch_block
          || die->parent->tag == DW_TAG_subprogram)
        return 0;
      return 1;

    default:
      return 0;
    }
}

/* Compute the fully qualified name of DIE in CU.  If PHYSNAME is nonzero,
   compute the physname for the object, which include a method's
   formal parameters (C++/Java) and return type (Java).

   For Ada, return the DIE's linkage name rather than the fully qualified
   name.  PHYSNAME is ignored..

   The result is allocated on the objfile_obstack and canonicalized.  */

static const char *
dwarf2_compute_name (char *name, struct die_info *die, struct dwarf2_cu *cu,
                     int physname)
{
  if (name == NULL)
    name = dwarf2_name (die, cu);

  /* For Fortran GDB prefers DW_AT_*linkage_name if present but otherwise
     compute it by typename_concat inside GDB.  */
  if (cu->language == language_ada
      || (cu->language == language_fortran && physname))
    {
      /* For Ada unit, we prefer the linkage name over the name, as
         the former contains the exported name, which the user expects
         to be able to reference.  Ideally, we want the user to be able
         to reference this entity using either natural or linkage name,
         but we haven't started looking at this enhancement yet.  */
      struct attribute *attr;

      attr = dwarf2_attr (die, DW_AT_linkage_name, cu);
      if (attr == NULL)
        attr = dwarf2_attr (die, DW_AT_MIPS_linkage_name, cu);
      if (attr && DW_STRING (attr))
        return DW_STRING (attr);
    }

  /* These are the only languages we know how to qualify names in.  */
  if (name != NULL
      && (cu->language == language_cplus || cu->language == language_java
          || cu->language == language_fortran))
    {
      if (die_needs_namespace (die, cu))
        {
          long length;
          char *prefix;
          struct ui_file *buf;

          prefix = determine_prefix (die, cu);
          buf = mem_fileopen ();
          if (*prefix != '\0')
            {
              char *prefixed_name = typename_concat (NULL, prefix, name,
                                                     physname, cu);

              fputs_unfiltered (prefixed_name, buf);
              xfree (prefixed_name);
            }
          else
            fputs_unfiltered (name ? name : "", buf);

          /* For Java and C++ methods, append formal parameter type
             information, if PHYSNAME.  */

          if (physname && die->tag == DW_TAG_subprogram
              && (cu->language == language_cplus
                  || cu->language == language_java))
            {
              struct type *type = read_type_die (die, cu);

              c_type_print_args (type, buf, 0, cu->language);

              if (cu->language == language_java)
                {
                  /* For java, we must append the return type to method
                     names. */
                  if (die->tag == DW_TAG_subprogram)
                    java_print_type (TYPE_TARGET_TYPE (type), "", buf,
                                     0, 0);
                }
              else if (cu->language == language_cplus)
                {
                  if (TYPE_NFIELDS (type) > 0
                      && TYPE_FIELD_ARTIFICIAL (type, 0)
                      && TYPE_CONST (TYPE_TARGET_TYPE (TYPE_FIELD_TYPE (type, 0))))
                    fputs_unfiltered (" const", buf);
                }
            }

          name = ui_file_obsavestring (buf, &cu->objfile->objfile_obstack,
                                       &length);
          ui_file_delete (buf);

          if (cu->language == language_cplus)
            {
              char *cname
                = dwarf2_canonicalize_name (name, cu,
                                            &cu->objfile->objfile_obstack);

              if (cname != NULL)
                name = cname;
            }
        }
    }

  return name;
}

/* Return the fully qualified name of DIE, based on its DW_AT_name.
   If scope qualifiers are appropriate they will be added.  The result
   will be allocated on the objfile_obstack, or NULL if the DIE does
   not have a name.  NAME may either be from a previous call to
   dwarf2_name or NULL.

   The output string will be canonicalized (if C++/Java). */

static const char *
dwarf2_full_name (char *name, struct die_info *die, struct dwarf2_cu *cu)
{
  return dwarf2_compute_name (name, die, cu, 0);
}

/* Construct a physname for the given DIE in CU.  NAME may either be
   from a previous call to dwarf2_name or NULL.  The result will be
   allocated on the objfile_objstack or NULL if the DIE does not have a
   name.

   The output string will be canonicalized (if C++/Java).  */

static const char *
dwarf2_physname (char *name, struct die_info *die, struct dwarf2_cu *cu)
{
  return dwarf2_compute_name (name, die, cu, 1);
}

/* Read the import statement specified by the given die and record it.  */

static void
read_import_statement (struct die_info *die, struct dwarf2_cu *cu)
{
  struct attribute *import_attr;
  struct die_info *imported_die;
  struct dwarf2_cu *imported_cu;
  const char *imported_name;
  const char *imported_name_prefix;
  const char *canonical_name;
  const char *import_alias;
  const char *imported_declaration = NULL;
  const char *import_prefix;

  char *temp;

  import_attr = dwarf2_attr (die, DW_AT_import, cu);
  if (import_attr == NULL)
    {
      complaint (&symfile_complaints, _("Tag '%s' has no DW_AT_import"),
                 dwarf_tag_name (die->tag));
      return;
    }

  imported_cu = cu;
  imported_die = follow_die_ref_or_sig (die, import_attr, &imported_cu);
  imported_name = dwarf2_name (imported_die, imported_cu);
  if (imported_name == NULL)
    {
      /* GCC bug: https://bugzilla.redhat.com/show_bug.cgi?id=506524

        The import in the following code:
        namespace A
          {
            typedef int B;
          }

        int main ()
          {
            using A::B;
            B b;
            return b;
          }

        ...
         <2><51>: Abbrev Number: 3 (DW_TAG_imported_declaration)
            <52>   DW_AT_decl_file   : 1
            <53>   DW_AT_decl_line   : 6
            <54>   DW_AT_import      : <0x75>
         <2><58>: Abbrev Number: 4 (DW_TAG_typedef)
            <59>   DW_AT_name        : B
            <5b>   DW_AT_decl_file   : 1
            <5c>   DW_AT_decl_line   : 2
            <5d>   DW_AT_type        : <0x6e>
        ...
         <1><75>: Abbrev Number: 7 (DW_TAG_base_type)
            <76>   DW_AT_byte_size   : 4
            <77>   DW_AT_encoding    : 5        (signed)

        imports the wrong die ( 0x75 instead of 0x58 ).
        This case will be ignored until the gcc bug is fixed.  */
      return;
    }

  /* Figure out the local name after import.  */
  import_alias = dwarf2_name (die, cu);

  /* Figure out where the statement is being imported to.  */
  import_prefix = determine_prefix (die, cu);

  /* Figure out what the scope of the imported die is and prepend it
     to the name of the imported die.  */
  imported_name_prefix = determine_prefix (imported_die, imported_cu);

  if (imported_die->tag != DW_TAG_namespace
      && imported_die->tag != DW_TAG_module)
    {
      imported_declaration = imported_name;
      canonical_name = imported_name_prefix;
    }
  else if (strlen (imported_name_prefix) > 0)
    {
      temp = alloca (strlen (imported_name_prefix)
                     + 2 + strlen (imported_name) + 1);
      strcpy (temp, imported_name_prefix);
      strcat (temp, "::");
      strcat (temp, imported_name);
      canonical_name = temp;
    }
  else
    canonical_name = imported_name;

  cp_add_using_directive (import_prefix,
                          canonical_name,
                          import_alias,
                          imported_declaration,
                          &cu->objfile->objfile_obstack);
}

static void
initialize_cu_func_list (struct dwarf2_cu *cu)
{
  cu->first_fn = cu->last_fn = cu->cached_fn = NULL;
}

static void
free_cu_line_header (void *arg)
{
  struct dwarf2_cu *cu = arg;

  free_line_header (cu->line_header);
  cu->line_header = NULL;
}

static void
find_file_and_directory (struct die_info *die, struct dwarf2_cu *cu,
                         char **name, char **comp_dir)
{
  struct attribute *attr;

  *name = NULL;
  *comp_dir = NULL;

  /* Find the filename.  Do not use dwarf2_name here, since the filename
     is not a source language identifier.  */
  attr = dwarf2_attr (die, DW_AT_name, cu);
  if (attr)
    {
      *name = DW_STRING (attr);
    }

  attr = dwarf2_attr (die, DW_AT_comp_dir, cu);
  if (attr)
    *comp_dir = DW_STRING (attr);
  else if (*name != NULL && IS_ABSOLUTE_PATH (*name))
    {
      *comp_dir = ldirname (*name);
      if (*comp_dir != NULL)
        make_cleanup (xfree, *comp_dir);
    }
  if (*comp_dir != NULL)
    {
      /* Irix 6.2 native cc prepends <machine>.: to the compilation
         directory, get rid of it.  */
      char *cp = strchr (*comp_dir, ':');

      if (cp && cp != *comp_dir && cp[-1] == '.' && cp[1] == '/')
        *comp_dir = cp + 1;
    }

  if (*name == NULL)
    *name = "<unknown>";
}

static void
read_file_scope (struct die_info *die, struct dwarf2_cu *cu)
{
  struct objfile *objfile = cu->objfile;
  struct cleanup *back_to = make_cleanup (null_cleanup, 0);
  CORE_ADDR lowpc = ((CORE_ADDR) -1);
  CORE_ADDR highpc = ((CORE_ADDR) 0);
  struct attribute *attr;
  char *name = NULL;
  char *comp_dir = NULL;
  struct die_info *child_die;
  bfd *abfd = objfile->obfd;
  struct line_header *line_header = 0;
  CORE_ADDR baseaddr;

  baseaddr = ANOFFSET (objfile->section_offsets, SECT_OFF_TEXT (objfile));

  get_scope_pc_bounds (die, &lowpc, &highpc, cu);

  /* If we didn't find a lowpc, set it to highpc to avoid complaints
     from finish_block.  */
  if (lowpc == ((CORE_ADDR) -1))
    lowpc = highpc;
  lowpc += baseaddr;
  highpc += baseaddr;

  find_file_and_directory (die, cu, &name, &comp_dir);

  attr = dwarf2_attr (die, DW_AT_language, cu);
  if (attr)
    {
      set_cu_language (DW_UNSND (attr), cu);
    }

  attr = dwarf2_attr (die, DW_AT_producer, cu);
  if (attr)
    cu->producer = DW_STRING (attr);

  /* We assume that we're processing GCC output. */
  processing_gcc_compilation = 2;

  processing_has_namespace_info = 0;

  start_symtab (name, comp_dir, lowpc);
  record_debugformat ("DWARF 2");
  record_producer (cu->producer);

  initialize_cu_func_list (cu);

  /* Decode line number information if present.  We do this before
     processing child DIEs, so that the line header table is available
     for DW_AT_decl_file.  */
  attr = dwarf2_attr (die, DW_AT_stmt_list, cu);
  if (attr)
    {
      unsigned int line_offset = DW_UNSND (attr);
      line_header = dwarf_decode_line_header (line_offset, abfd, cu);
      if (line_header)
        {
          cu->line_header = line_header;
          make_cleanup (free_cu_line_header, cu);
          dwarf_decode_lines (line_header, comp_dir, abfd, cu, NULL);
        }
    }

  /* Process all dies in compilation unit.  */
  if (die->child != NULL)
    {
      child_die = die->child;
      while (child_die && child_die->tag)
        {
          process_die (child_die, cu);
          child_die = sibling_die (child_die);
        }
    }

  /* Decode macro information, if present.  Dwarf 2 macro information
     refers to information in the line number info statement program
     header, so we can only read it if we've read the header
     successfully.  */
  attr = dwarf2_attr (die, DW_AT_macro_info, cu);
  if (attr && line_header)
    {
      unsigned int macro_offset = DW_UNSND (attr);

      dwarf_decode_macros (line_header, macro_offset,
                           comp_dir, abfd, cu);
    }
  do_cleanups (back_to);
}

/* For TUs we want to skip the first top level sibling if it's not the
   actual type being defined by this TU.  In this case the first top
   level sibling is there to provide context only.  */

static void
read_type_unit_scope (struct die_info *die, struct dwarf2_cu *cu)
{
  struct objfile *objfile = cu->objfile;
  struct cleanup *back_to = make_cleanup (null_cleanup, 0);
  CORE_ADDR lowpc;
  struct attribute *attr;
  char *name = NULL;
  char *comp_dir = NULL;
  struct die_info *child_die;
  bfd *abfd = objfile->obfd;

  /* start_symtab needs a low pc, but we don't really have one.
     Do what read_file_scope would do in the absence of such info.  */
  lowpc = ANOFFSET (objfile->section_offsets, SECT_OFF_TEXT (objfile));

  /* Find the filename.  Do not use dwarf2_name here, since the filename
     is not a source language identifier.  */
  attr = dwarf2_attr (die, DW_AT_name, cu);
  if (attr)
    name = DW_STRING (attr);

  attr = dwarf2_attr (die, DW_AT_comp_dir, cu);
  if (attr)
    comp_dir = DW_STRING (attr);
  else if (name != NULL && IS_ABSOLUTE_PATH (name))
    {
      comp_dir = ldirname (name);
      if (comp_dir != NULL)
        make_cleanup (xfree, comp_dir);
    }

  if (name == NULL)
    name = "<unknown>";

  attr = dwarf2_attr (die, DW_AT_language, cu);
  if (attr)
    set_cu_language (DW_UNSND (attr), cu);

  /* This isn't technically needed today.  It is done for symmetry
     with read_file_scope.  */
  attr = dwarf2_attr (die, DW_AT_producer, cu);
  if (attr)
    cu->producer = DW_STRING (attr);

  /* We assume that we're processing GCC output. */
  processing_gcc_compilation = 2;

  processing_has_namespace_info = 0;

  start_symtab (name, comp_dir, lowpc);
  record_debugformat ("DWARF 2");
  record_producer (cu->producer);

  /* Process the dies in the type unit.  */
  if (die->child == NULL)
    {
      dump_die_for_error (die);
      error (_("Dwarf Error: Missing children for type unit [in module %s]"),
             bfd_get_filename (abfd));
    }

  child_die = die->child;

  while (child_die && child_die->tag)
    {
      process_die (child_die, cu);

      child_die = sibling_die (child_die);
    }

  do_cleanups (back_to);
}

static void
add_to_cu_func_list (const char *name, CORE_ADDR lowpc, CORE_ADDR highpc,
                     struct dwarf2_cu *cu)
{
  struct function_range *thisfn;

  thisfn = (struct function_range *)
    obstack_alloc (&cu->comp_unit_obstack, sizeof (struct function_range));
  thisfn->name = name;
  thisfn->lowpc = lowpc;
  thisfn->highpc = highpc;
  thisfn->seen_line = 0;
  thisfn->next = NULL;

  if (cu->last_fn == NULL)
      cu->first_fn = thisfn;
  else
      cu->last_fn->next = thisfn;

  cu->last_fn = thisfn;
}

/* qsort helper for inherit_abstract_dies.  */

static int
unsigned_int_compar (const void *ap, const void *bp)
{
  unsigned int a = *(unsigned int *) ap;
  unsigned int b = *(unsigned int *) bp;

  return (a > b) - (b > a);
}

/* DW_AT_abstract_origin inherits whole DIEs (not just their attributes).
   Inherit only the children of the DW_AT_abstract_origin DIE not being already
   referenced by DW_AT_abstract_origin from the children of the current DIE.  */

static void
inherit_abstract_dies (struct die_info *die, struct dwarf2_cu *cu)
{
  struct die_info *child_die;
  unsigned die_children_count;
  /* CU offsets which were referenced by children of the current DIE.  */
  unsigned *offsets;
  unsigned *offsets_end, *offsetp;
  /* Parent of DIE - referenced by DW_AT_abstract_origin.  */
  struct die_info *origin_die;
  /* Iterator of the ORIGIN_DIE children.  */
  struct die_info *origin_child_die;
  struct cleanup *cleanups;
  struct attribute *attr;

  attr = dwarf2_attr (die, DW_AT_abstract_origin, cu);
  if (!attr)
    return;

  origin_die = follow_die_ref (die, attr, &cu);
  if (die->tag != origin_die->tag
      && !(die->tag == DW_TAG_inlined_subroutine
           && origin_die->tag == DW_TAG_subprogram))
    complaint (&symfile_complaints,
               _("DIE 0x%x and its abstract origin 0x%x have different tags"),
               die->offset, origin_die->offset);

  child_die = die->child;
  die_children_count = 0;
  while (child_die && child_die->tag)
    {
      child_die = sibling_die (child_die);
      die_children_count++;
    }
  offsets = xmalloc (sizeof (*offsets) * die_children_count);
  cleanups = make_cleanup (xfree, offsets);

  offsets_end = offsets;
  child_die = die->child;
  while (child_die && child_die->tag)
    {
      /* For each CHILD_DIE, find the corresponding child of
         ORIGIN_DIE.  If there is more than one layer of
         DW_AT_abstract_origin, follow them all; there shouldn't be,
         but GCC versions at least through 4.4 generate this (GCC PR
         40573).  */
      struct die_info *child_origin_die = child_die;

      while (1)
        {
          attr = dwarf2_attr (child_origin_die, DW_AT_abstract_origin, cu);
          if (attr == NULL)
            break;
          child_origin_die = follow_die_ref (child_origin_die, attr, &cu);
        }

      /* According to DWARF3 3.3.8.2 #3 new entries without their abstract
         counterpart may exist.  */
      if (child_origin_die != child_die)
        {
          if (child_die->tag != child_origin_die->tag
              && !(child_die->tag == DW_TAG_inlined_subroutine
                   && child_origin_die->tag == DW_TAG_subprogram))
            complaint (&symfile_complaints,
                       _("Child DIE 0x%x and its abstract origin 0x%x have "
                         "different tags"), child_die->offset,
                       child_origin_die->offset);
          if (child_origin_die->parent != origin_die)
            complaint (&symfile_complaints,
                       _("Child DIE 0x%x and its abstract origin 0x%x have "
                         "different parents"), child_die->offset,
                       child_origin_die->offset);
          else
            *offsets_end++ = child_origin_die->offset;
        }
      child_die = sibling_die (child_die);
    }
  qsort (offsets, offsets_end - offsets, sizeof (*offsets),
         unsigned_int_compar);
  for (offsetp = offsets + 1; offsetp < offsets_end; offsetp++)
    if (offsetp[-1] == *offsetp)
      complaint (&symfile_complaints, _("Multiple children of DIE 0x%x refer "
                                        "to DIE 0x%x as their abstract origin"),
                 die->offset, *offsetp);

  offsetp = offsets;
  origin_child_die = origin_die->child;
  while (origin_child_die && origin_child_die->tag)
    {
      /* Is ORIGIN_CHILD_DIE referenced by any of the DIE children?  */
      while (offsetp < offsets_end && *offsetp < origin_child_die->offset)
        offsetp++;
      if (offsetp >= offsets_end || *offsetp > origin_child_die->offset)
        {
          /* Found that ORIGIN_CHILD_DIE is really not referenced.  */
          process_die (origin_child_die, cu);
        }
      origin_child_die = sibling_die (origin_child_die);
    }

  do_cleanups (cleanups);
}

static void
read_func_scope (struct die_info *die, struct dwarf2_cu *cu)
{
  struct objfile *objfile = cu->objfile;
  struct context_stack *new;
  CORE_ADDR lowpc;
  CORE_ADDR highpc;
  struct die_info *child_die;
  struct attribute *attr, *call_line, *call_file;
  char *name;
  CORE_ADDR baseaddr;
  struct block *block;
  int inlined_func = (die->tag == DW_TAG_inlined_subroutine);

  if (inlined_func)
    {
      /* If we do not have call site information, we can't show the
         caller of this inlined function.  That's too confusing, so
         only use the scope for local variables.  */
      call_line = dwarf2_attr (die, DW_AT_call_line, cu);
      call_file = dwarf2_attr (die, DW_AT_call_file, cu);
      if (call_line == NULL || call_file == NULL)
        {
          read_lexical_block_scope (die, cu);
          return;
        }
    }

  baseaddr = ANOFFSET (objfile->section_offsets, SECT_OFF_TEXT (objfile));

  name = dwarf2_name (die, cu);

  /* Ignore functions with missing or empty names.  These are actually
     illegal according to the DWARF standard.  */
  if (name == NULL)
    {
      complaint (&symfile_complaints,
                 _("missing name for subprogram DIE at %d"), die->offset);
      return;
    }

  /* Ignore functions with missing or invalid low and high pc attributes.  */
  if (!dwarf2_get_pc_bounds (die, &lowpc, &highpc, cu, NULL))
    {
      attr = dwarf2_attr (die, DW_AT_external, cu);
      if (!attr || !DW_UNSND (attr))
        complaint (&symfile_complaints,
                   _("cannot get low and high bounds for subprogram DIE at %d"),
                   die->offset);
      return;
    }

  lowpc += baseaddr;
  highpc += baseaddr;

  /* Record the function range for dwarf_decode_lines.  */
  add_to_cu_func_list (name, lowpc, highpc, cu);

  new = push_context (0, lowpc);
  new->name = new_symbol (die, read_type_die (die, cu), cu);

  /* If there is a location expression for DW_AT_frame_base, record
     it.  */
  attr = dwarf2_attr (die, DW_AT_frame_base, cu);
  if (attr)
    /* FIXME: cagney/2004-01-26: The DW_AT_frame_base's location
       expression is being recorded directly in the function's symbol
       and not in a separate frame-base object.  I guess this hack is
       to avoid adding some sort of frame-base adjunct/annex to the
       function's symbol :-(.  The problem with doing this is that it
       results in a function symbol with a location expression that
       has nothing to do with the location of the function, ouch!  The
       relationship should be: a function's symbol has-a frame base; a
       frame-base has-a location expression.  */
    dwarf2_symbol_mark_computed (attr, new->name, cu);

  cu->list_in_scope = &local_symbols;

  if (die->child != NULL)
    {
      child_die = die->child;
      while (child_die && child_die->tag)
        {
          process_die (child_die, cu);
          child_die = sibling_die (child_die);
        }
    }

  inherit_abstract_dies (die, cu);

  /* If we have a DW_AT_specification, we might need to import using
     directives from the context of the specification DIE.  See the
     comment in determine_prefix.  */
  if (cu->language == language_cplus
      && dwarf2_attr (die, DW_AT_specification, cu))
    {
      struct dwarf2_cu *spec_cu = cu;
      struct die_info *spec_die = die_specification (die, &spec_cu);

      while (spec_die)
        {
          child_die = spec_die->child;
          while (child_die && child_die->tag)
            {
              if (child_die->tag == DW_TAG_imported_module)
                process_die (child_die, spec_cu);
              child_die = sibling_die (child_die);
            }

          /* In some cases, GCC generates specification DIEs that
             themselves contain DW_AT_specification attributes.  */
          spec_die = die_specification (spec_die, &spec_cu);
        }
    }

  new = pop_context ();
  /* Make a block for the local symbols within.  */
  block = finish_block (new->name, &local_symbols, new->old_blocks,
                        lowpc, highpc, objfile);

  /* For C++, set the block's scope.  */
  if (cu->language == language_cplus || cu->language == language_fortran)
    cp_set_block_scope (new->name, block, &objfile->objfile_obstack,
                        determine_prefix (die, cu),
                        processing_has_namespace_info);

  /* If we have address ranges, record them.  */
  dwarf2_record_block_ranges (die, block, baseaddr, cu);

  /* In C++, we can have functions nested inside functions (e.g., when
     a function declares a class that has methods).  This means that
     when we finish processing a function scope, we may need to go
     back to building a containing block's symbol lists.  */
  local_symbols = new->locals;
  param_symbols = new->params;
  using_directives = new->using_directives;

  /* If we've finished processing a top-level function, subsequent
     symbols go in the file symbol list.  */
  if (outermost_context_p ())
    cu->list_in_scope = &file_symbols;
}

/* Process all the DIES contained within a lexical block scope.  Start
   a new scope, process the dies, and then close the scope.  */

static void
read_lexical_block_scope (struct die_info *die, struct dwarf2_cu *cu)
{
  struct objfile *objfile = cu->objfile;
  struct context_stack *new;
  CORE_ADDR lowpc, highpc;
  struct die_info *child_die;
  CORE_ADDR baseaddr;

  baseaddr = ANOFFSET (objfile->section_offsets, SECT_OFF_TEXT (objfile));

  /* Ignore blocks with missing or invalid low and high pc attributes.  */
  /* ??? Perhaps consider discontiguous blocks defined by DW_AT_ranges
     as multiple lexical blocks?  Handling children in a sane way would
     be nasty.  Might be easier to properly extend generic blocks to
     describe ranges.  */
  if (!dwarf2_get_pc_bounds (die, &lowpc, &highpc, cu, NULL))
    return;
  lowpc += baseaddr;
  highpc += baseaddr;

  push_context (0, lowpc);
  if (die->child != NULL)
    {
      child_die = die->child;
      while (child_die && child_die->tag)
        {
          process_die (child_die, cu);
          child_die = sibling_die (child_die);
        }
    }
  new = pop_context ();

  if (local_symbols != NULL || using_directives != NULL)
    {
      struct block *block
        = finish_block (0, &local_symbols, new->old_blocks, new->start_addr,
                        highpc, objfile);

      /* Note that recording ranges after traversing children, as we
         do here, means that recording a parent's ranges entails
         walking across all its children's ranges as they appear in
         the address map, which is quadratic behavior.

         It would be nicer to record the parent's ranges before
         traversing its children, simply overriding whatever you find
         there.  But since we don't even decide whether to create a
         block until after we've traversed its children, that's hard
         to do.  */
      dwarf2_record_block_ranges (die, block, baseaddr, cu);
    }
  local_symbols = new->locals;
  using_directives = new->using_directives;
}

/* Get low and high pc attributes from DW_AT_ranges attribute value OFFSET.
   Return 1 if the attributes are present and valid, otherwise, return 0.
   If RANGES_PST is not NULL we should setup `objfile->psymtabs_addrmap'.  */

static int
dwarf2_ranges_read (unsigned offset, CORE_ADDR *low_return,
                    CORE_ADDR *high_return, struct dwarf2_cu *cu,
                    struct partial_symtab *ranges_pst)
{
  struct objfile *objfile = cu->objfile;
  struct comp_unit_head *cu_header = &cu->header;
  bfd *obfd = objfile->obfd;
  unsigned int addr_size = cu_header->addr_size;
  CORE_ADDR mask = ~(~(CORE_ADDR)1 << (addr_size * 8 - 1));
  /* Base address selection entry.  */
  CORE_ADDR base;
  int found_base;
  unsigned int dummy;
  gdb_byte *buffer;
  CORE_ADDR marker;
  int low_set;
  CORE_ADDR low = 0;
  CORE_ADDR high = 0;
  CORE_ADDR baseaddr;

  found_base = cu->base_known;
  base = cu->base_address;

  dwarf2_read_section (objfile, &dwarf2_per_objfile->ranges);
  if (offset >= dwarf2_per_objfile->ranges.size)
    {
      complaint (&symfile_complaints,
                 _("Offset %d out of bounds for DW_AT_ranges attribute"),
                 offset);
      return 0;
    }
  buffer = dwarf2_per_objfile->ranges.buffer + offset;

  /* Read in the largest possible address.  */
  marker = read_address (obfd, buffer, cu, &dummy);
  if ((marker & mask) == mask)
    {
      /* If we found the largest possible address, then
         read the base address.  */
      base = read_address (obfd, buffer + addr_size, cu, &dummy);
      buffer += 2 * addr_size;
      offset += 2 * addr_size;
      found_base = 1;
    }

  low_set = 0;

  baseaddr = ANOFFSET (objfile->section_offsets, SECT_OFF_TEXT (objfile));

  while (1)
    {
      CORE_ADDR range_beginning, range_end;

      range_beginning = read_address (obfd, buffer, cu, &dummy);
      buffer += addr_size;
      range_end = read_address (obfd, buffer, cu, &dummy);
      buffer += addr_size;
      offset += 2 * addr_size;

      /* An end of list marker is a pair of zero addresses.  */
      if (range_beginning == 0 && range_end == 0)
        /* Found the end of list entry.  */
        break;

      /* Each base address selection entry is a pair of 2 values.
         The first is the largest possible address, the second is
         the base address.  Check for a base address here.  */
      if ((range_beginning & mask) == mask)
        {
          /* If we found the largest possible address, then
             read the base address.  */
          base = read_address (obfd, buffer + addr_size, cu, &dummy);
          found_base = 1;
          continue;
        }

      if (!found_base)
        {
          /* We have no valid base address for the ranges
             data.  */
          complaint (&symfile_complaints,
                     _("Invalid .debug_ranges data (no base address)"));
          return 0;
        }

      range_beginning += base;
      range_end += base;

      if (ranges_pst != NULL && range_beginning < range_end)
        addrmap_set_empty (objfile->psymtabs_addrmap,
                           range_beginning + baseaddr, range_end - 1 + baseaddr,
                           ranges_pst);

      /* FIXME: This is recording everything as a low-high
         segment of consecutive addresses.  We should have a
         data structure for discontiguous block ranges
         instead.  */
      if (! low_set)
        {
          low = range_beginning;
          high = range_end;
          low_set = 1;
        }
      else
        {
          if (range_beginning < low)
            low = range_beginning;
          if (range_end > high)
            high = range_end;
        }
    }

  if (! low_set)
    /* If the first entry is an end-of-list marker, the range
       describes an empty scope, i.e. no instructions.  */
    return 0;

  if (low_return)
    *low_return = low;
  if (high_return)
    *high_return = high;
  return 1;
}

/* Get low and high pc attributes from a die.  Return 1 if the attributes
   are present and valid, otherwise, return 0.  Return -1 if the range is
   discontinuous, i.e. derived from DW_AT_ranges information.  */
static int
dwarf2_get_pc_bounds (struct die_info *die, CORE_ADDR *lowpc,
                      CORE_ADDR *highpc, struct dwarf2_cu *cu,
                      struct partial_symtab *pst)
{
  struct attribute *attr;
  CORE_ADDR low = 0;
  CORE_ADDR high = 0;
  int ret = 0;

  attr = dwarf2_attr (die, DW_AT_high_pc, cu);
  if (attr)
    {
      high = DW_ADDR (attr);
      attr = dwarf2_attr (die, DW_AT_low_pc, cu);
      if (attr)
        low = DW_ADDR (attr);
      else
        /* Found high w/o low attribute.  */
        return 0;

      /* Found consecutive range of addresses.  */
      ret = 1;
    }
  else
    {
      attr = dwarf2_attr (die, DW_AT_ranges, cu);
      if (attr != NULL)
        {
          /* Value of the DW_AT_ranges attribute is the offset in the
             .debug_ranges section.  */
          if (!dwarf2_ranges_read (DW_UNSND (attr), &low, &high, cu, pst))
            return 0;
          /* Found discontinuous range of addresses.  */
          ret = -1;
        }
    }

  if (high < low)
    return 0;

  /* When using the GNU linker, .gnu.linkonce. sections are used to
     eliminate duplicate copies of functions and vtables and such.
     The linker will arbitrarily choose one and discard the others.
     The AT_*_pc values for such functions refer to local labels in
     these sections.  If the section from that file was discarded, the
     labels are not in the output, so the relocs get a value of 0.
     If this is a discarded function, mark the pc bounds as invalid,
     so that GDB will ignore it.  */
  if (low == 0 && !dwarf2_per_objfile->has_section_at_zero)
    return 0;

  *lowpc = low;
  *highpc = high;
  return ret;
}

/* Assuming that DIE represents a subprogram DIE or a lexical block, get
   its low and high PC addresses.  Do nothing if these addresses could not
   be determined.  Otherwise, set LOWPC to the low address if it is smaller,
   and HIGHPC to the high address if greater than HIGHPC.  */

static void
dwarf2_get_subprogram_pc_bounds (struct die_info *die,
                                 CORE_ADDR *lowpc, CORE_ADDR *highpc,
                                 struct dwarf2_cu *cu)
{
  CORE_ADDR low, high;
  struct die_info *child = die->child;

  if (dwarf2_get_pc_bounds (die, &low, &high, cu, NULL))
    {
      *lowpc = min (*lowpc, low);
      *highpc = max (*highpc, high);
    }

  /* If the language does not allow nested subprograms (either inside
     subprograms or lexical blocks), we're done.  */
  if (cu->language != language_ada)
    return;

  /* Check all the children of the given DIE.  If it contains nested
     subprograms, then check their pc bounds.  Likewise, we need to
     check lexical blocks as well, as they may also contain subprogram
     definitions.  */
  while (child && child->tag)
    {
      if (child->tag == DW_TAG_subprogram
          || child->tag == DW_TAG_lexical_block)
        dwarf2_get_subprogram_pc_bounds (child, lowpc, highpc, cu);
      child = sibling_die (child);
    }
}

/* Get the low and high pc's represented by the scope DIE, and store
   them in *LOWPC and *HIGHPC.  If the correct values can't be
   determined, set *LOWPC to -1 and *HIGHPC to 0.  */

static void
get_scope_pc_bounds (struct die_info *die,
                     CORE_ADDR *lowpc, CORE_ADDR *highpc,
                     struct dwarf2_cu *cu)
{
  CORE_ADDR best_low = (CORE_ADDR) -1;
  CORE_ADDR best_high = (CORE_ADDR) 0;
  CORE_ADDR current_low, current_high;

  if (dwarf2_get_pc_bounds (die, &current_low, &current_high, cu, NULL))
    {
      best_low = current_low;
      best_high = current_high;
    }
  else
    {
      struct die_info *child = die->child;

      while (child && child->tag)
        {
          switch (child->tag) {
          case DW_TAG_subprogram:
            dwarf2_get_subprogram_pc_bounds (child, &best_low, &best_high, cu);
            break;
          case DW_TAG_namespace:
          case DW_TAG_module:
            /* FIXME: carlton/2004-01-16: Should we do this for
               DW_TAG_class_type/DW_TAG_structure_type, too?  I think
               that current GCC's always emit the DIEs corresponding
               to definitions of methods of classes as children of a
               DW_TAG_compile_unit or DW_TAG_namespace (as opposed to
               the DIEs giving the declarations, which could be
               anywhere).  But I don't see any reason why the
               standards says that they have to be there.  */
            get_scope_pc_bounds (child, &current_low, &current_high, cu);

            if (current_low != ((CORE_ADDR) -1))
              {
                best_low = min (best_low, current_low);
                best_high = max (best_high, current_high);
              }
            break;
          default:
            /* Ignore. */
            break;
          }

          child = sibling_die (child);
        }
    }

  *lowpc = best_low;
  *highpc = best_high;
}

/* Record the address ranges for BLOCK, offset by BASEADDR, as given
   in DIE.  */
static void
dwarf2_record_block_ranges (struct die_info *die, struct block *block,
                            CORE_ADDR baseaddr, struct dwarf2_cu *cu)
{
  struct attribute *attr;

  attr = dwarf2_attr (die, DW_AT_high_pc, cu);
  if (attr)
    {
      CORE_ADDR high = DW_ADDR (attr);

      attr = dwarf2_attr (die, DW_AT_low_pc, cu);
      if (attr)
        {
          CORE_ADDR low = DW_ADDR (attr);

          record_block_range (block, baseaddr + low, baseaddr + high - 1);
        }
    }

  attr = dwarf2_attr (die, DW_AT_ranges, cu);
  if (attr)
    {
      bfd *obfd = cu->objfile->obfd;

      /* The value of the DW_AT_ranges attribute is the offset of the
         address range list in the .debug_ranges section.  */
      unsigned long offset = DW_UNSND (attr);
      gdb_byte *buffer = dwarf2_per_objfile->ranges.buffer + offset;

      /* For some target architectures, but not others, the
         read_address function sign-extends the addresses it returns.
         To recognize base address selection entries, we need a
         mask.  */
      unsigned int addr_size = cu->header.addr_size;
      CORE_ADDR base_select_mask = ~(~(CORE_ADDR)1 << (addr_size * 8 - 1));

      /* The base address, to which the next pair is relative.  Note
         that this 'base' is a DWARF concept: most entries in a range
         list are relative, to reduce the number of relocs against the
         debugging information.  This is separate from this function's
         'baseaddr' argument, which GDB uses to relocate debugging
         information from a shared library based on the address at
         which the library was loaded.  */
      CORE_ADDR base = cu->base_address;
      int base_known = cu->base_known;

      gdb_assert (dwarf2_per_objfile->ranges.readin);
      if (offset >= dwarf2_per_objfile->ranges.size)
        {
          complaint (&symfile_complaints,
                     _("Offset %lu out of bounds for DW_AT_ranges attribute"),
                     offset);
          return;
        }

      for (;;)
        {
          unsigned int bytes_read;
          CORE_ADDR start, end;

          start = read_address (obfd, buffer, cu, &bytes_read);
          buffer += bytes_read;
          end = read_address (obfd, buffer, cu, &bytes_read);
          buffer += bytes_read;

          /* Did we find the end of the range list?  */
          if (start == 0 && end == 0)
            break;

          /* Did we find a base address selection entry?  */
          else if ((start & base_select_mask) == base_select_mask)
            {
              base = end;
              base_known = 1;
            }

          /* We found an ordinary address range.  */
          else
            {
              if (!base_known)
                {
                  complaint (&symfile_complaints,
                             _("Invalid .debug_ranges data (no base address)"));
                  return;
                }

              record_block_range (block,
                                  baseaddr + base + start,
                                  baseaddr + base + end - 1);
            }
        }
    }
}

/* Add an aggregate field to the field list.  */

static void
dwarf2_add_field (struct field_info *fip, struct die_info *die,
                  struct dwarf2_cu *cu)
{
  struct objfile *objfile = cu->objfile;
  struct gdbarch *gdbarch = get_objfile_arch (objfile);
  struct nextfield *new_field;
  struct attribute *attr;
  struct field *fp;
  char *fieldname = "";

  /* Allocate a new field list entry and link it in.  */
  new_field = (struct nextfield *) xmalloc (sizeof (struct nextfield));
  make_cleanup (xfree, new_field);
  memset (new_field, 0, sizeof (struct nextfield));

  if (die->tag == DW_TAG_inheritance)
    {
      new_field->next = fip->baseclasses;
      fip->baseclasses = new_field;
    }
  else
    {
      new_field->next = fip->fields;
      fip->fields = new_field;
    }
  fip->nfields++;

  /* Handle accessibility and virtuality of field.
     The default accessibility for members is public, the default
     accessibility for inheritance is private.  */
  if (die->tag != DW_TAG_inheritance)
    new_field->accessibility = DW_ACCESS_public;
  else
    new_field->accessibility = DW_ACCESS_private;
  new_field->virtuality = DW_VIRTUALITY_none;

  attr = dwarf2_attr (die, DW_AT_accessibility, cu);
  if (attr)
    new_field->accessibility = DW_UNSND (attr);
  if (new_field->accessibility != DW_ACCESS_public)
    fip->non_public_fields = 1;
  attr = dwarf2_attr (die, DW_AT_virtuality, cu);
  if (attr)
    new_field->virtuality = DW_UNSND (attr);

  fp = &new_field->field;

  if (die->tag == DW_TAG_member && ! die_is_declaration (die, cu))
    {
      /* Data member other than a C++ static data member.  */

      /* Get type of field.  */
      fp->type = die_type (die, cu);

      SET_FIELD_BITPOS (*fp, 0);

      /* Get bit size of field (zero if none).  */
      attr = dwarf2_attr (die, DW_AT_bit_size, cu);
      if (attr)
        {
          FIELD_BITSIZE (*fp) = DW_UNSND (attr);
        }
      else
        {
          FIELD_BITSIZE (*fp) = 0;
        }

      /* Get bit offset of field.  */
      attr = dwarf2_attr (die, DW_AT_data_member_location, cu);
      if (attr)
        {
          int byte_offset = 0;

          if (attr_form_is_section_offset (attr))
            dwarf2_complex_location_expr_complaint ();
          else if (attr_form_is_constant (attr))
            byte_offset = dwarf2_get_attr_constant_value (attr, 0);
          else if (attr_form_is_block (attr))
            byte_offset = decode_locdesc (DW_BLOCK (attr), cu);
          else
            dwarf2_complex_location_expr_complaint ();

          SET_FIELD_BITPOS (*fp, byte_offset * bits_per_byte);
        }
      attr = dwarf2_attr (die, DW_AT_bit_offset, cu);
      if (attr)
        {
          if (gdbarch_bits_big_endian (gdbarch))
            {
              /* For big endian bits, the DW_AT_bit_offset gives the
                 additional bit offset from the MSB of the containing
                 anonymous object to the MSB of the field.  We don't
                 have to do anything special since we don't need to
                 know the size of the anonymous object.  */
              FIELD_BITPOS (*fp) += DW_UNSND (attr);
            }
          else
            {
              /* For little endian bits, compute the bit offset to the
                 MSB of the anonymous object, subtract off the number of
                 bits from the MSB of the field to the MSB of the
                 object, and then subtract off the number of bits of
                 the field itself.  The result is the bit offset of
                 the LSB of the field.  */
              int anonymous_size;
              int bit_offset = DW_UNSND (attr);

              attr = dwarf2_attr (die, DW_AT_byte_size, cu);
              if (attr)
                {
                  /* The size of the anonymous object containing
                     the bit field is explicit, so use the
                     indicated size (in bytes).  */
                  anonymous_size = DW_UNSND (attr);
                }
              else
                {
                  /* The size of the anonymous object containing
                     the bit field must be inferred from the type
                     attribute of the data member containing the
                     bit field.  */
                  anonymous_size = TYPE_LENGTH (fp->type);
                }
              FIELD_BITPOS (*fp) += anonymous_size * bits_per_byte
                - bit_offset - FIELD_BITSIZE (*fp);
            }
        }

      /* Get name of field.  */
      fieldname = dwarf2_name (die, cu);
      if (fieldname == NULL)
        fieldname = "";

      /* The name is already allocated along with this objfile, so we don't
         need to duplicate it for the type.  */
      fp->name = fieldname;

      /* Change accessibility for artificial fields (e.g. virtual table
         pointer or virtual base class pointer) to private.  */
      if (dwarf2_attr (die, DW_AT_artificial, cu))
        {
          FIELD_ARTIFICIAL (*fp) = 1;
          new_field->accessibility = DW_ACCESS_private;
          fip->non_public_fields = 1;
        }
    }
  else if (die->tag == DW_TAG_member || die->tag == DW_TAG_variable)
    {
      /* C++ static member.  */

      /* NOTE: carlton/2002-11-05: It should be a DW_TAG_member that
         is a declaration, but all versions of G++ as of this writing
         (so through at least 3.2.1) incorrectly generate
         DW_TAG_variable tags.  */

      char *physname;

      /* Get name of field.  */
      fieldname = dwarf2_name (die, cu);
      if (fieldname == NULL)
        return;

      attr = dwarf2_attr (die, DW_AT_const_value, cu);
      if (attr
          /* Only create a symbol if this is an external value.
             new_symbol checks this and puts the value in the global symbol
             table, which we want.  If it is not external, new_symbol
             will try to put the value in cu->list_in_scope which is wrong.  */
          && dwarf2_flag_true_p (die, DW_AT_external, cu))
        {
          /* A static const member, not much different than an enum as far as
             we're concerned, except that we can support more types.  */
          new_symbol (die, NULL, cu);
        }

      /* Get physical name.  */
      physname = (char *) dwarf2_physname (fieldname, die, cu);

      /* The name is already allocated along with this objfile, so we don't
         need to duplicate it for the type.  */
      SET_FIELD_PHYSNAME (*fp, physname ? physname : "");
      FIELD_TYPE (*fp) = die_type (die, cu);
      FIELD_NAME (*fp) = fieldname;
    }
  else if (die->tag == DW_TAG_inheritance)
    {
      /* C++ base class field.  */
      attr = dwarf2_attr (die, DW_AT_data_member_location, cu);
      if (attr)
        {
          int byte_offset = 0;

          if (attr_form_is_section_offset (attr))
            dwarf2_complex_location_expr_complaint ();
          else if (attr_form_is_constant (attr))
            byte_offset = dwarf2_get_attr_constant_value (attr, 0);
          else if (attr_form_is_block (attr))
            byte_offset = decode_locdesc (DW_BLOCK (attr), cu);
          else
            dwarf2_complex_location_expr_complaint ();

          SET_FIELD_BITPOS (*fp, byte_offset * bits_per_byte);
        }
      FIELD_BITSIZE (*fp) = 0;
      FIELD_TYPE (*fp) = die_type (die, cu);
      FIELD_NAME (*fp) = type_name_no_tag (fp->type);
      fip->nbaseclasses++;
    }
}

/* Add a typedef defined in the scope of the FIP's class.  */

static void
dwarf2_add_typedef (struct field_info *fip, struct die_info *die,
                    struct dwarf2_cu *cu)
{
  struct objfile *objfile = cu->objfile;
  struct gdbarch *gdbarch = get_objfile_arch (objfile);
  struct typedef_field_list *new_field;
  struct attribute *attr;
  struct typedef_field *fp;
  char *fieldname = "";

  /* Allocate a new field list entry and link it in.  */
  new_field = xzalloc (sizeof (*new_field));
  make_cleanup (xfree, new_field);

  gdb_assert (die->tag == DW_TAG_typedef);

  fp = &new_field->field;

  /* Get name of field.  */
  fp->name = dwarf2_name (die, cu);
  if (fp->name == NULL)
    return;

  fp->type = read_type_die (die, cu);

  new_field->next = fip->typedef_field_list;
  fip->typedef_field_list = new_field;
  fip->typedef_field_list_count++;
}

/* Create the vector of fields, and attach it to the type.  */

static void
dwarf2_attach_fields_to_type (struct field_info *fip, struct type *type,
                              struct dwarf2_cu *cu)
{
  int nfields = fip->nfields;

  /* Record the field count, allocate space for the array of fields,
     and create blank accessibility bitfields if necessary.  */
  TYPE_NFIELDS (type) = nfields;
  TYPE_FIELDS (type) = (struct field *)
    TYPE_ALLOC (type, sizeof (struct field) * nfields);
  memset (TYPE_FIELDS (type), 0, sizeof (struct field) * nfields);

  if (fip->non_public_fields && cu->language != language_ada)
    {
      ALLOCATE_CPLUS_STRUCT_TYPE (type);

      TYPE_FIELD_PRIVATE_BITS (type) =
        (B_TYPE *) TYPE_ALLOC (type, B_BYTES (nfields));
      B_CLRALL (TYPE_FIELD_PRIVATE_BITS (type), nfields);

      TYPE_FIELD_PROTECTED_BITS (type) =
        (B_TYPE *) TYPE_ALLOC (type, B_BYTES (nfields));
      B_CLRALL (TYPE_FIELD_PROTECTED_BITS (type), nfields);

      TYPE_FIELD_IGNORE_BITS (type) =
        (B_TYPE *) TYPE_ALLOC (type, B_BYTES (nfields));
      B_CLRALL (TYPE_FIELD_IGNORE_BITS (type), nfields);
    }

  /* If the type has baseclasses, allocate and clear a bit vector for
     TYPE_FIELD_VIRTUAL_BITS.  */
  if (fip->nbaseclasses && cu->language != language_ada)
    {
      int num_bytes = B_BYTES (fip->nbaseclasses);
      unsigned char *pointer;

      ALLOCATE_CPLUS_STRUCT_TYPE (type);
      pointer = TYPE_ALLOC (type, num_bytes);
      TYPE_FIELD_VIRTUAL_BITS (type) = pointer;
      B_CLRALL (TYPE_FIELD_VIRTUAL_BITS (type), fip->nbaseclasses);
      TYPE_N_BASECLASSES (type) = fip->nbaseclasses;
    }

  /* Copy the saved-up fields into the field vector.  Start from the head
     of the list, adding to the tail of the field array, so that they end
     up in the same order in the array in which they were added to the list.  */
  while (nfields-- > 0)
    {
      struct nextfield *fieldp;

      if (fip->fields)
        {
          fieldp = fip->fields;
          fip->fields = fieldp->next;
        }
      else
        {
          fieldp = fip->baseclasses;
          fip->baseclasses = fieldp->next;
        }

      TYPE_FIELD (type, nfields) = fieldp->field;
      switch (fieldp->accessibility)
        {
        case DW_ACCESS_private:
          if (cu->language != language_ada)
            SET_TYPE_FIELD_PRIVATE (type, nfields);
          break;

        case DW_ACCESS_protected:
          if (cu->language != language_ada)
            SET_TYPE_FIELD_PROTECTED (type, nfields);
          break;

        case DW_ACCESS_public:
          break;

        default:
          /* Unknown accessibility.  Complain and treat it as public.  */
          {
            complaint (&symfile_complaints, _("unsupported accessibility %d"),
                       fieldp->accessibility);
          }
          break;
        }
      if (nfields < fip->nbaseclasses)
        {
          switch (fieldp->virtuality)
            {
            case DW_VIRTUALITY_virtual:
            case DW_VIRTUALITY_pure_virtual:
              if (cu->language == language_ada)
                error ("unexpected virtuality in component of Ada type");
              SET_TYPE_FIELD_VIRTUAL (type, nfields);
              break;
            }
        }
    }
}

/* Add a member function to the proper fieldlist.  */

static void
dwarf2_add_member_fn (struct field_info *fip, struct die_info *die,
                      struct type *type, struct dwarf2_cu *cu)
{
  struct objfile *objfile = cu->objfile;
  struct attribute *attr;
  struct fnfieldlist *flp;
  int i;
  struct fn_field *fnp;
  char *fieldname;
  char *physname;
  struct nextfnfield *new_fnfield;
  struct type *this_type;

  if (cu->language == language_ada)
    error ("unexpected member function in Ada type");

  /* Get name of member function.  */
  fieldname = dwarf2_name (die, cu);
  if (fieldname == NULL)
    return;

  /* Get the mangled name.  */
  physname = (char *) dwarf2_physname (fieldname, die, cu);

  /* Look up member function name in fieldlist.  */
  for (i = 0; i < fip->nfnfields; i++)
    {
      if (strcmp (fip->fnfieldlists[i].name, fieldname) == 0)
        break;
    }

  /* Create new list element if necessary.  */
  if (i < fip->nfnfields)
    flp = &fip->fnfieldlists[i];
  else
    {
      if ((fip->nfnfields % DW_FIELD_ALLOC_CHUNK) == 0)
        {
          fip->fnfieldlists = (struct fnfieldlist *)
            xrealloc (fip->fnfieldlists,
                      (fip->nfnfields + DW_FIELD_ALLOC_CHUNK)
                      * sizeof (struct fnfieldlist));
          if (fip->nfnfields == 0)
            make_cleanup (free_current_contents, &fip->fnfieldlists);
        }
      flp = &fip->fnfieldlists[fip->nfnfields];
      flp->name = fieldname;
      flp->length = 0;
      flp->head = NULL;
      fip->nfnfields++;
    }

  /* Create a new member function field and chain it to the field list
     entry. */
  new_fnfield = (struct nextfnfield *) xmalloc (sizeof (struct nextfnfield));
  make_cleanup (xfree, new_fnfield);
  memset (new_fnfield, 0, sizeof (struct nextfnfield));
  new_fnfield->next = flp->head;
  flp->head = new_fnfield;
  flp->length++;

  /* Fill in the member function field info.  */
  fnp = &new_fnfield->fnfield;
  /* The name is already allocated along with this objfile, so we don't
     need to duplicate it for the type.  */
  fnp->physname = physname ? physname : "";
  fnp->type = alloc_type (objfile);
  this_type = read_type_die (die, cu);
  if (this_type && TYPE_CODE (this_type) == TYPE_CODE_FUNC)
    {
      int nparams = TYPE_NFIELDS (this_type);

      /* TYPE is the domain of this method, and THIS_TYPE is the type
           of the method itself (TYPE_CODE_METHOD).  */
      smash_to_method_type (fnp->type, type,
                            TYPE_TARGET_TYPE (this_type),
                            TYPE_FIELDS (this_type),
                            TYPE_NFIELDS (this_type),
                            TYPE_VARARGS (this_type));

      /* Handle static member functions.
         Dwarf2 has no clean way to discern C++ static and non-static
         member functions. G++ helps GDB by marking the first
         parameter for non-static member functions (which is the
         this pointer) as artificial. We obtain this information
         from read_subroutine_type via TYPE_FIELD_ARTIFICIAL.  */
      if (nparams == 0 || TYPE_FIELD_ARTIFICIAL (this_type, 0) == 0)
        fnp->voffset = VOFFSET_STATIC;
    }
  else
    complaint (&symfile_complaints, _("member function type missing for '%s'"),
               physname);

  /* Get fcontext from DW_AT_containing_type if present.  */
  if (dwarf2_attr (die, DW_AT_containing_type, cu) != NULL)
    fnp->fcontext = die_containing_type (die, cu);

  /* dwarf2 doesn't have stubbed physical names, so the setting of is_const
     and is_volatile is irrelevant, as it is needed by gdb_mangle_name only.  */

  /* Get accessibility.  */
  attr = dwarf2_attr (die, DW_AT_accessibility, cu);
  if (attr)
    {
      switch (DW_UNSND (attr))
        {
        case DW_ACCESS_private:
          fnp->is_private = 1;
          break;
        case DW_ACCESS_protected:
          fnp->is_protected = 1;
          break;
        }
    }

  /* Check for artificial methods.  */
  attr = dwarf2_attr (die, DW_AT_artificial, cu);
  if (attr && DW_UNSND (attr) != 0)
    fnp->is_artificial = 1;

  /* Get index in virtual function table if it is a virtual member
     function.  For older versions of GCC, this is an offset in the
     appropriate virtual table, as specified by DW_AT_containing_type.
     For everyone else, it is an expression to be evaluated relative
     to the object address.  */

  attr = dwarf2_attr (die, DW_AT_vtable_elem_location, cu);
  if (attr)
    {
      if (attr_form_is_block (attr) && DW_BLOCK (attr)->size > 0)
        {
          if (DW_BLOCK (attr)->data[0] == DW_OP_constu)
            {
              /* Old-style GCC.  */
              fnp->voffset = decode_locdesc (DW_BLOCK (attr), cu) + 2;
            }
          else if (DW_BLOCK (attr)->data[0] == DW_OP_deref
                   || (DW_BLOCK (attr)->size > 1
                       && DW_BLOCK (attr)->data[0] == DW_OP_deref_size
                       && DW_BLOCK (attr)->data[1] == cu->header.addr_size))
            {
              struct dwarf_block blk;
              int offset;

              offset = (DW_BLOCK (attr)->data[0] == DW_OP_deref
                        ? 1 : 2);
              blk.size = DW_BLOCK (attr)->size - offset;
              blk.data = DW_BLOCK (attr)->data + offset;
              fnp->voffset = decode_locdesc (DW_BLOCK (attr), cu);
              if ((fnp->voffset % cu->header.addr_size) != 0)
                dwarf2_complex_location_expr_complaint ();
              else
                fnp->voffset /= cu->header.addr_size;
              fnp->voffset += 2;
            }
          else
            dwarf2_complex_location_expr_complaint ();

          if (!fnp->fcontext)
            fnp->fcontext = TYPE_TARGET_TYPE (TYPE_FIELD_TYPE (this_type, 0));
        }
      else if (attr_form_is_section_offset (attr))
        {
          dwarf2_complex_location_expr_complaint ();
        }
      else
        {
          dwarf2_invalid_attrib_class_complaint ("DW_AT_vtable_elem_location",
                                                 fieldname);
        }
    }
  else
    {
      attr = dwarf2_attr (die, DW_AT_virtuality, cu);
      if (attr && DW_UNSND (attr))
        {
          /* GCC does this, as of 2008-08-25; PR debug/37237.  */
          complaint (&symfile_complaints,
                     _("Member function \"%s\" (offset %d) is virtual but the vtable offset is not specified"),
                     fieldname, die->offset);
          ALLOCATE_CPLUS_STRUCT_TYPE (type);
          TYPE_CPLUS_DYNAMIC (type) = 1;
        }
    }
}

/* Create the vector of member function fields, and attach it to the type.  */

static void
dwarf2_attach_fn_fields_to_type (struct field_info *fip, struct type *type,
                                 struct dwarf2_cu *cu)
{
  struct fnfieldlist *flp;
  int total_length = 0;
  int i;

  if (cu->language == language_ada)
    error ("unexpected member functions in Ada type");

  ALLOCATE_CPLUS_STRUCT_TYPE (type);
  TYPE_FN_FIELDLISTS (type) = (struct fn_fieldlist *)
    TYPE_ALLOC (type, sizeof (struct fn_fieldlist) * fip->nfnfields);

  for (i = 0, flp = fip->fnfieldlists; i < fip->nfnfields; i++, flp++)
    {
      struct nextfnfield *nfp = flp->head;
      struct fn_fieldlist *fn_flp = &TYPE_FN_FIELDLIST (type, i);
      int k;

      TYPE_FN_FIELDLIST_NAME (type, i) = flp->name;
      TYPE_FN_FIELDLIST_LENGTH (type, i) = flp->length;
      fn_flp->fn_fields = (struct fn_field *)
        TYPE_ALLOC (type, sizeof (struct fn_field) * flp->length);
      for (k = flp->length; (k--, nfp); nfp = nfp->next)
        fn_flp->fn_fields[k] = nfp->fnfield;

      total_length += flp->length;
    }

  TYPE_NFN_FIELDS (type) = fip->nfnfields;
  TYPE_NFN_FIELDS_TOTAL (type) = total_length;
}

/* Returns non-zero if NAME is the name of a vtable member in CU's
   language, zero otherwise.  */
static int
is_vtable_name (const char *name, struct dwarf2_cu *cu)
{
  static const char vptr[] = "_vptr";
  static const char vtable[] = "vtable";

  /* Look for the C++ and Java forms of the vtable.  */
  if ((cu->language == language_java
       && strncmp (name, vtable, sizeof (vtable) - 1) == 0)
       || (strncmp (name, vptr, sizeof (vptr) - 1) == 0
       && is_cplus_marker (name[sizeof (vptr) - 1])))
    return 1;

  return 0;
}

/* GCC outputs unnamed structures that are really pointers to member
   functions, with the ABI-specified layout.  If TYPE describes
   such a structure, smash it into a member function type.

   GCC shouldn't do this; it should just output pointer to member DIEs.
   This is GCC PR debug/28767.  */

static void
quirk_gcc_member_function_pointer (struct type *type, struct objfile *objfile)
{
  struct type *pfn_type, *domain_type, *new_type;

  /* Check for a structure with no name and two children.  */
  if (TYPE_CODE (type) != TYPE_CODE_STRUCT || TYPE_NFIELDS (type) != 2)
    return;

  /* Check for __pfn and __delta members.  */
  if (TYPE_FIELD_NAME (type, 0) == NULL
      || strcmp (TYPE_FIELD_NAME (type, 0), "__pfn") != 0
      || TYPE_FIELD_NAME (type, 1) == NULL
      || strcmp (TYPE_FIELD_NAME (type, 1), "__delta") != 0)
    return;

  /* Find the type of the method.  */
  pfn_type = TYPE_FIELD_TYPE (type, 0);
  if (pfn_type == NULL
      || TYPE_CODE (pfn_type) != TYPE_CODE_PTR
      || TYPE_CODE (TYPE_TARGET_TYPE (pfn_type)) != TYPE_CODE_FUNC)
    return;

  /* Look for the "this" argument.  */
  pfn_type = TYPE_TARGET_TYPE (pfn_type);
  if (TYPE_NFIELDS (pfn_type) == 0
      /* || TYPE_FIELD_TYPE (pfn_type, 0) == NULL */
      || TYPE_CODE (TYPE_FIELD_TYPE (pfn_type, 0)) != TYPE_CODE_PTR)
    return;

  domain_type = TYPE_TARGET_TYPE (TYPE_FIELD_TYPE (pfn_type, 0));
  new_type = alloc_type (objfile);
  smash_to_method_type (new_type, domain_type, TYPE_TARGET_TYPE (pfn_type),
                        TYPE_FIELDS (pfn_type), TYPE_NFIELDS (pfn_type),
                        TYPE_VARARGS (pfn_type));
  smash_to_methodptr_type (type, new_type);
}

/* Called when we find the DIE that starts a structure or union scope
   (definition) to process all dies that define the members of the
   structure or union.

   NOTE: we need to call struct_type regardless of whether or not the
   DIE has an at_name attribute, since it might be an anonymous
   structure or union.  This gets the type entered into our set of
   user defined types.

   However, if the structure is incomplete (an opaque struct/union)
   then suppress creating a symbol table entry for it since gdb only
   wants to find the one with the complete definition.  Note that if
   it is complete, we just call new_symbol, which does it's own
   checking about whether the struct/union is anonymous or not (and
   suppresses creating a symbol table entry itself).  */

static struct type *
read_structure_type (struct die_info *die, struct dwarf2_cu *cu)
{
  struct objfile *objfile = cu->objfile;
  struct type *type;
  struct attribute *attr;
  char *name;
  struct cleanup *back_to;

  /* If the definition of this type lives in .debug_types, read that type.
     Don't follow DW_AT_specification though, that will take us back up
     the chain and we want to go down.  */
  attr = dwarf2_attr_no_follow (die, DW_AT_signature, cu);
  if (attr)
    {
      struct dwarf2_cu *type_cu = cu;
      struct die_info *type_die = follow_die_ref_or_sig (die, attr, &type_cu);

      /* We could just recurse on read_structure_type, but we need to call
         get_die_type to ensure only one type for this DIE is created.
         This is important, for example, because for c++ classes we need
         TYPE_NAME set which is only done by new_symbol.  Blech.  */
      type = read_type_die (type_die, type_cu);
      return set_die_type (die, type, cu);
    }

  back_to = make_cleanup (null_cleanup, 0);

  type = alloc_type (objfile);
  INIT_CPLUS_SPECIFIC (type);

  name = dwarf2_name (die, cu);
  if (name != NULL)
    {
      if (cu->language == language_cplus
          || cu->language == language_java)
        {
          TYPE_TAG_NAME (type) = (char *) dwarf2_full_name (name, die, cu);
          if (die->tag == DW_TAG_structure_type
              || die->tag == DW_TAG_class_type)
            TYPE_NAME (type) = TYPE_TAG_NAME (type);
        }
      else
        {
          /* The name is already allocated along with this objfile, so
             we don't need to duplicate it for the type.  */
          TYPE_TAG_NAME (type) = (char *) name;
          if (die->tag == DW_TAG_class_type)
            TYPE_NAME (type) = TYPE_TAG_NAME (type);
        }
    }

  if (die->tag == DW_TAG_structure_type)
    {
      TYPE_CODE (type) = TYPE_CODE_STRUCT;
    }
  else if (die->tag == DW_TAG_union_type)
    {
      TYPE_CODE (type) = TYPE_CODE_UNION;
    }
  else
    {
      TYPE_CODE (type) = TYPE_CODE_CLASS;
    }

  if (cu->language == language_cplus && die->tag == DW_TAG_class_type)
    TYPE_DECLARED_CLASS (type) = 1;

  attr = dwarf2_attr (die, DW_AT_byte_size, cu);
  if (attr)
    {
      TYPE_LENGTH (type) = DW_UNSND (attr);
    }
  else
    {
      TYPE_LENGTH (type) = 0;
    }

  TYPE_STUB_SUPPORTED (type) = 1;
  if (die_is_declaration (die, cu))
    TYPE_STUB (type) = 1;
  else if (attr == NULL && die->child == NULL
           && producer_is_realview (cu->producer))
    /* RealView does not output the required DW_AT_declaration
       on incomplete types.  */
    TYPE_STUB (type) = 1;

  /* We need to add the type field to the die immediately so we don't
     infinitely recurse when dealing with pointers to the structure
     type within the structure itself. */
  set_die_type (die, type, cu);

  /* set_die_type should be already done.  */
  set_descriptive_type (type, die, cu);

  if (die->child != NULL && ! die_is_declaration (die, cu))
    {
      struct field_info fi;
      struct die_info *child_die;

      memset (&fi, 0, sizeof (struct field_info));

      child_die = die->child;

      while (child_die && child_die->tag)
        {
          if (child_die->tag == DW_TAG_member
              || child_die->tag == DW_TAG_variable)
            {
              /* NOTE: carlton/2002-11-05: A C++ static data member
                 should be a DW_TAG_member that is a declaration, but
                 all versions of G++ as of this writing (so through at
                 least 3.2.1) incorrectly generate DW_TAG_variable
                 tags for them instead.  */
              dwarf2_add_field (&fi, child_die, cu);
            }
          else if (child_die->tag == DW_TAG_subprogram)
            {
              /* C++ member function. */
              dwarf2_add_member_fn (&fi, child_die, type, cu);
            }
          else if (child_die->tag == DW_TAG_inheritance)
            {
              /* C++ base class field.  */
              dwarf2_add_field (&fi, child_die, cu);
            }
          else if (child_die->tag == DW_TAG_typedef)
            dwarf2_add_typedef (&fi, child_die, cu);
          child_die = sibling_die (child_die);
        }

      /* Attach fields and member functions to the type.  */
      if (fi.nfields)
        dwarf2_attach_fields_to_type (&fi, type, cu);
      if (fi.nfnfields)
        {
          dwarf2_attach_fn_fields_to_type (&fi, type, cu);

          /* Get the type which refers to the base class (possibly this
             class itself) which contains the vtable pointer for the current
             class from the DW_AT_containing_type attribute.  This use of
             DW_AT_containing_type is a GNU extension.  */

          if (dwarf2_attr (die, DW_AT_containing_type, cu) != NULL)
            {
              struct type *t = die_containing_type (die, cu);

              TYPE_VPTR_BASETYPE (type) = t;
              if (type == t)
                {
                  int i;

                  /* Our own class provides vtbl ptr.  */
                  for (i = TYPE_NFIELDS (t) - 1;
                       i >= TYPE_N_BASECLASSES (t);
                       --i)
                    {
                      char *fieldname = TYPE_FIELD_NAME (t, i);

                      if (is_vtable_name (fieldname, cu))
                        {
                          TYPE_VPTR_FIELDNO (type) = i;
                          break;
                        }
                    }

                  /* Complain if virtual function table field not found.  */
                  if (i < TYPE_N_BASECLASSES (t))
                    complaint (&symfile_complaints,
                               _("virtual function table pointer not found when defining class '%s'"),
                               TYPE_TAG_NAME (type) ? TYPE_TAG_NAME (type) :
                               "");
                }
              else
                {
                  TYPE_VPTR_FIELDNO (type) = TYPE_VPTR_FIELDNO (t);
                }
            }
          else if (cu->producer
                   && strncmp (cu->producer,
                               "IBM(R) XL C/C++ Advanced Edition", 32) == 0)
            {
              /* The IBM XLC compiler does not provide direct indication
                 of the containing type, but the vtable pointer is
                 always named __vfp.  */

              int i;

              for (i = TYPE_NFIELDS (type) - 1;
                   i >= TYPE_N_BASECLASSES (type);
                   --i)
                {
                  if (strcmp (TYPE_FIELD_NAME (type, i), "__vfp") == 0)
                    {
                      TYPE_VPTR_FIELDNO (type) = i;
                      TYPE_VPTR_BASETYPE (type) = type;
                      break;
                    }
                }
            }
        }

      /* Copy fi.typedef_field_list linked list elements content into the
         allocated array TYPE_TYPEDEF_FIELD_ARRAY (type).  */
      if (fi.typedef_field_list)
        {
          int i = fi.typedef_field_list_count;

          ALLOCATE_CPLUS_STRUCT_TYPE (type);
          TYPE_TYPEDEF_FIELD_ARRAY (type)
            = TYPE_ALLOC (type, sizeof (TYPE_TYPEDEF_FIELD (type, 0)) * i);
          TYPE_TYPEDEF_FIELD_COUNT (type) = i;

          /* Reverse the list order to keep the debug info elements order.  */
          while (--i >= 0)
            {
              struct typedef_field *dest, *src;

              dest = &TYPE_TYPEDEF_FIELD (type, i);
              src = &fi.typedef_field_list->field;
              fi.typedef_field_list = fi.typedef_field_list->next;
              *dest = *src;
            }
        }
    }

  quirk_gcc_member_function_pointer (type, cu->objfile);

  do_cleanups (back_to);
  return type;
}

static void
process_structure_scope (struct die_info *die, struct dwarf2_cu *cu)
{
  struct die_info *child_die = die->child;
  struct type *this_type;

  this_type = get_die_type (die, cu);
  if (this_type == NULL)
    this_type = read_structure_type (die, cu);

  /* NOTE: carlton/2004-03-16: GCC 3.4 (or at least one of its
     snapshots) has been known to create a die giving a declaration
     for a class that has, as a child, a die giving a definition for a
     nested class.  So we have to process our children even if the
     current die is a declaration.  Normally, of course, a declaration
     won't have any children at all.  */

  while (child_die != NULL && child_die->tag)
    {
      if (child_die->tag == DW_TAG_member
          || child_die->tag == DW_TAG_variable
          || child_die->tag == DW_TAG_inheritance)
        {
          /* Do nothing.  */
        }
      else
        process_die (child_die, cu);

      child_die = sibling_die (child_die);
    }

  /* Do not consider external references.  According to the DWARF standard,
     these DIEs are identified by the fact that they have no byte_size
     attribute, and a declaration attribute.  */
  if (dwarf2_attr (die, DW_AT_byte_size, cu) != NULL
      || !die_is_declaration (die, cu))
    new_symbol (die, this_type, cu);
}

/* Given a DW_AT_enumeration_type die, set its type.  We do not
   complete the type's fields yet, or create any symbols.  */

static struct type *
read_enumeration_type (struct die_info *die, struct dwarf2_cu *cu)
{
  struct objfile *objfile = cu->objfile;
  struct type *type;
  struct attribute *attr;
  const char *name;

  /* If the definition of this type lives in .debug_types, read that type.
     Don't follow DW_AT_specification though, that will take us back up
     the chain and we want to go down.  */
  attr = dwarf2_attr_no_follow (die, DW_AT_signature, cu);
  if (attr)
    {
      struct dwarf2_cu *type_cu = cu;
      struct die_info *type_die = follow_die_ref_or_sig (die, attr, &type_cu);

      type = read_type_die (type_die, type_cu);
      return set_die_type (die, type, cu);
    }

  type = alloc_type (objfile);

  TYPE_CODE (type) = TYPE_CODE_ENUM;
  name = dwarf2_full_name (NULL, die, cu);
  if (name != NULL)
    TYPE_TAG_NAME (type) = (char *) name;

  attr = dwarf2_attr (die, DW_AT_byte_size, cu);
  if (attr)
    {
      TYPE_LENGTH (type) = DW_UNSND (attr);
    }
  else
    {
      TYPE_LENGTH (type) = 0;
    }

  /* The enumeration DIE can be incomplete.  In Ada, any type can be
     declared as private in the package spec, and then defined only
     inside the package body.  Such types are known as Taft Amendment
     Types.  When another package uses such a type, an incomplete DIE
     may be generated by the compiler.  */
  if (die_is_declaration (die, cu))
    TYPE_STUB (type) = 1;

  return set_die_type (die, type, cu);
}

/* Given a pointer to a die which begins an enumeration, process all
   the dies that define the members of the enumeration, and create the
   symbol for the enumeration type.

   NOTE: We reverse the order of the element list.  */

static void
process_enumeration_scope (struct die_info *die, struct dwarf2_cu *cu)
{
  struct die_info *child_die;
  struct field *fields;
  struct symbol *sym;
  int num_fields;
  int unsigned_enum = 1;
  char *name;
  struct type *this_type;

  num_fields = 0;
  fields = NULL;
  this_type = get_die_type (die, cu);
  if (this_type == NULL)
    this_type = read_enumeration_type (die, cu);
  if (die->child != NULL)
    {
      child_die = die->child;
      while (child_die && child_die->tag)
        {
          if (child_die->tag != DW_TAG_enumerator)
            {
              process_die (child_die, cu);
            }
          else
            {
              name = dwarf2_name (child_die, cu);
              if (name)
                {
                  sym = new_symbol (child_die, this_type, cu);
                  if (SYMBOL_VALUE (sym) < 0)
                    unsigned_enum = 0;

                  if ((num_fields % DW_FIELD_ALLOC_CHUNK) == 0)
                    {
                      fields = (struct field *)
                        xrealloc (fields,
                                  (num_fields + DW_FIELD_ALLOC_CHUNK)
                                  * sizeof (struct field));
                    }

                  FIELD_NAME (fields[num_fields]) = SYMBOL_LINKAGE_NAME (sym);
                  FIELD_TYPE (fields[num_fields]) = NULL;
                  SET_FIELD_BITPOS (fields[num_fields], SYMBOL_VALUE (sym));
                  FIELD_BITSIZE (fields[num_fields]) = 0;

                  num_fields++;
                }
            }

          child_die = sibling_die (child_die);
        }

      if (num_fields)
        {
          TYPE_NFIELDS (this_type) = num_fields;
          TYPE_FIELDS (this_type) = (struct field *)
            TYPE_ALLOC (this_type, sizeof (struct field) * num_fields);
          memcpy (TYPE_FIELDS (this_type), fields,
                  sizeof (struct field) * num_fields);
          xfree (fields);
        }
      if (unsigned_enum)
        TYPE_UNSIGNED (this_type) = 1;
    }

  new_symbol (die, this_type, cu);
}

/* Extract all information from a DW_TAG_array_type DIE and put it in
   the DIE's type field.  For now, this only handles one dimensional
   arrays.  */

static struct type *
read_array_type (struct die_info *die, struct dwarf2_cu *cu)
{
  struct objfile *objfile = cu->objfile;
  struct die_info *child_die;
  struct type *type;
  struct type *element_type, *range_type, *index_type;
  struct type **range_types = NULL;
  struct attribute *attr;
  int ndim = 0;
  struct cleanup *back_to;
  char *name;

  element_type = die_type (die, cu);

  /* The die_type call above may have already set the type for this DIE.  */
  type = get_die_type (die, cu);
  if (type)
    return type;

  /* Irix 6.2 native cc creates array types without children for
     arrays with unspecified length.  */
  if (die->child == NULL)
    {
      index_type = objfile_type (objfile)->builtin_int;
      range_type = create_range_type (NULL, index_type, 0, -1);
      type = create_array_type (NULL, element_type, range_type);
      return set_die_type (die, type, cu);
    }

  back_to = make_cleanup (null_cleanup, NULL);
  child_die = die->child;
  while (child_die && child_die->tag)
    {
      if (child_die->tag == DW_TAG_subrange_type)
        {
          struct type *child_type = read_type_die (child_die, cu);

          if (child_type != NULL)
            {
              /* The range type was succesfully read. Save it for
                 the array type creation.  */
              if ((ndim % DW_FIELD_ALLOC_CHUNK) == 0)
                {
                  range_types = (struct type **)
                    xrealloc (range_types, (ndim + DW_FIELD_ALLOC_CHUNK)
                              * sizeof (struct type *));
                  if (ndim == 0)
                    make_cleanup (free_current_contents, &range_types);
                }
              range_types[ndim++] = child_type;
            }
        }
      child_die = sibling_die (child_die);
    }

  /* Dwarf2 dimensions are output from left to right, create the
     necessary array types in backwards order.  */

  type = element_type;

  if (read_array_order (die, cu) == DW_ORD_col_major)
    {
      int i = 0;

      while (i < ndim)
        type = create_array_type (NULL, type, range_types[i++]);
    }
  else
    {
      while (ndim-- > 0)
        type = create_array_type (NULL, type, range_types[ndim]);
    }

  /* Understand Dwarf2 support for vector types (like they occur on
     the PowerPC w/ AltiVec).  Gcc just adds another attribute to the
     array type.  This is not part of the Dwarf2/3 standard yet, but a
     custom vendor extension.  The main difference between a regular
     array and the vector variant is that vectors are passed by value
     to functions.  */
  attr = dwarf2_attr (die, DW_AT_GNU_vector, cu);
  if (attr)
    make_vector_type (type);

  name = dwarf2_name (die, cu);
  if (name)
    TYPE_NAME (type) = name;

  /* Install the type in the die. */
  set_die_type (die, type, cu);

  /* set_die_type should be already done.  */
  set_descriptive_type (type, die, cu);

  do_cleanups (back_to);

  return type;
}

static enum dwarf_array_dim_ordering
read_array_order (struct die_info *die, struct dwarf2_cu *cu)
{
  struct attribute *attr;

  attr = dwarf2_attr (die, DW_AT_ordering, cu);

  if (attr) return DW_SND (attr);

  /*
    GNU F77 is a special case, as at 08/2004 array type info is the
    opposite order to the dwarf2 specification, but data is still
    laid out as per normal fortran.

    FIXME: dsl/2004-8-20: If G77 is ever fixed, this will also need
    version checking.
  */

  if (cu->language == language_fortran
      && cu->producer && strstr (cu->producer, "GNU F77"))
    {
      return DW_ORD_row_major;
    }

  switch (cu->language_defn->la_array_ordering)
    {
    case array_column_major:
      return DW_ORD_col_major;
    case array_row_major:
    default:
      return DW_ORD_row_major;
    };
}

/* Extract all information from a DW_TAG_set_type DIE and put it in
   the DIE's type field. */

static struct type *
read_set_type (struct die_info *die, struct dwarf2_cu *cu)
{
  struct type *domain_type, *set_type;
  struct attribute *attr;

  domain_type = die_type (die, cu);

  /* The die_type call above may have already set the type for this DIE.  */
  set_type = get_die_type (die, cu);
  if (set_type)
    return set_type;

  set_type = create_set_type (NULL, domain_type);

  attr = dwarf2_attr (die, DW_AT_byte_size, cu);
  if (attr)
    TYPE_LENGTH (set_type) = DW_UNSND (attr);

  return set_die_type (die, set_type, cu);
}

/* First cut: install each common block member as a global variable.  */

static void
read_common_block (struct die_info *die, struct dwarf2_cu *cu)
{
  struct die_info *child_die;
  struct attribute *attr;
  struct symbol *sym;
  CORE_ADDR base = (CORE_ADDR) 0;

  attr = dwarf2_attr (die, DW_AT_location, cu);
  if (attr)
    {
      /* Support the .debug_loc offsets */
      if (attr_form_is_block (attr))
        {
          base = decode_locdesc (DW_BLOCK (attr), cu);
        }
      else if (attr_form_is_section_offset (attr))
        {
          dwarf2_complex_location_expr_complaint ();
        }
      else
        {
          dwarf2_invalid_attrib_class_complaint ("DW_AT_location",
                                                 "common block member");
        }
    }
  if (die->child != NULL)
    {
      child_die = die->child;
      while (child_die && child_die->tag)
        {
          sym = new_symbol (child_die, NULL, cu);
          attr = dwarf2_attr (child_die, DW_AT_data_member_location, cu);
          if (attr)
            {
              CORE_ADDR byte_offset = 0;

              if (attr_form_is_section_offset (attr))
                dwarf2_complex_location_expr_complaint ();
              else if (attr_form_is_constant (attr))
                byte_offset = dwarf2_get_attr_constant_value (attr, 0);
              else if (attr_form_is_block (attr))
                byte_offset = decode_locdesc (DW_BLOCK (attr), cu);
              else
                dwarf2_complex_location_expr_complaint ();

              SYMBOL_VALUE_ADDRESS (sym) = base + byte_offset;
              add_symbol_to_list (sym, &global_symbols);
            }
          child_die = sibling_die (child_die);
        }
    }
}

/* Create a type for a C++ namespace.  */

static struct type *
read_namespace_type (struct die_info *die, struct dwarf2_cu *cu)
{
  struct objfile *objfile = cu->objfile;
  const char *previous_prefix, *name;
  int is_anonymous;
  struct type *type;

  /* For extensions, reuse the type of the original namespace.  */
  if (dwarf2_attr (die, DW_AT_extension, cu) != NULL)
    {
      struct die_info *ext_die;
      struct dwarf2_cu *ext_cu = cu;

      ext_die = dwarf2_extension (die, &ext_cu);
      type = read_type_die (ext_die, ext_cu);
      return set_die_type (die, type, cu);
    }

  name = namespace_name (die, &is_anonymous, cu);

  /* Now build the name of the current namespace.  */

  previous_prefix = determine_prefix (die, cu);
  if (previous_prefix[0] != '\0')
    name = typename_concat (&objfile->objfile_obstack,
                            previous_prefix, name, 0, cu);

  /* Create the type.  */
  type = init_type (TYPE_CODE_NAMESPACE, 0, 0, NULL,
                    objfile);
  TYPE_NAME (type) = (char *) name;
  TYPE_TAG_NAME (type) = TYPE_NAME (type);

  return set_die_type (die, type, cu);
}

/* Read a C++ namespace.  */

static void
read_namespace (struct die_info *die, struct dwarf2_cu *cu)
{
  struct objfile *objfile = cu->objfile;
  const char *name;
  int is_anonymous;

  /* Add a symbol associated to this if we haven't seen the namespace
     before.  Also, add a using directive if it's an anonymous
     namespace.  */

  if (dwarf2_attr (die, DW_AT_extension, cu) == NULL)
    {
      struct type *type;

      type = read_type_die (die, cu);
      new_symbol (die, type, cu);

      name = namespace_name (die, &is_anonymous, cu);
      if (is_anonymous)
        {
          const char *previous_prefix = determine_prefix (die, cu);

          cp_add_using_directive (previous_prefix, TYPE_NAME (type), NULL,
                                  NULL, &objfile->objfile_obstack);
        }
    }

  if (die->child != NULL)
    {
      struct die_info *child_die = die->child;

      while (child_die && child_die->tag)
        {
          process_die (child_die, cu);
          child_die = sibling_die (child_die);
        }
    }
}

/* Read a Fortran module as type.  This DIE can be only a declaration used for
   imported module.  Still we need that type as local Fortran "use ... only"
   declaration imports depend on the created type in determine_prefix.  */

static struct type *
read_module_type (struct die_info *die, struct dwarf2_cu *cu)
{
  struct objfile *objfile = cu->objfile;
  char *module_name;
  struct type *type;

  module_name = dwarf2_name (die, cu);
  if (!module_name)
    complaint (&symfile_complaints, _("DW_TAG_module has no name, offset 0x%x"),
               die->offset);
  type = init_type (TYPE_CODE_MODULE, 0, 0, module_name, objfile);

  /* determine_prefix uses TYPE_TAG_NAME.  */
  TYPE_TAG_NAME (type) = TYPE_NAME (type);

  return set_die_type (die, type, cu);
}

/* Read a Fortran module.  */

static void
read_module (struct die_info *die, struct dwarf2_cu *cu)
{
  struct die_info *child_die = die->child;

  while (child_die && child_die->tag)
    {
      process_die (child_die, cu);
      child_die = sibling_die (child_die);
    }
}

/* Return the name of the namespace represented by DIE.  Set
   *IS_ANONYMOUS to tell whether or not the namespace is an anonymous
   namespace.  */

static const char *
namespace_name (struct die_info *die, int *is_anonymous, struct dwarf2_cu *cu)
{
  struct die_info *current_die;
  const char *name = NULL;

  /* Loop through the extensions until we find a name.  */

  for (current_die = die;
       current_die != NULL;
       current_die = dwarf2_extension (die, &cu))
    {
      name = dwarf2_name (current_die, cu);
      if (name != NULL)
        break;
    }

  /* Is it an anonymous namespace?  */

  *is_anonymous = (name == NULL);
  if (*is_anonymous)
    name = "(anonymous namespace)";

  return name;
}

/* Extract all information from a DW_TAG_pointer_type DIE and add to
   the user defined type vector.  */

static struct type *
read_tag_pointer_type (struct die_info *die, struct dwarf2_cu *cu)
{
  struct gdbarch *gdbarch = get_objfile_arch (cu->objfile);
  struct comp_unit_head *cu_header = &cu->header;
  struct type *type;
  struct attribute *attr_byte_size;
  struct attribute *attr_address_class;
  int byte_size, addr_class;
  struct type *target_type;

  target_type = die_type (die, cu);

  /* The die_type call above may have already set the type for this DIE.  */
  type = get_die_type (die, cu);
  if (type)
    return type;

  type = lookup_pointer_type (target_type);

  attr_byte_size = dwarf2_attr (die, DW_AT_byte_size, cu);
  if (attr_byte_size)
    byte_size = DW_UNSND (attr_byte_size);
  else
    byte_size = cu_header->addr_size;

  attr_address_class = dwarf2_attr (die, DW_AT_address_class, cu);
  if (attr_address_class)
    addr_class = DW_UNSND (attr_address_class);
  else
    addr_class = DW_ADDR_none;

  /* If the pointer size or address class is different than the
     default, create a type variant marked as such and set the
     length accordingly.  */
  if (TYPE_LENGTH (type) != byte_size || addr_class != DW_ADDR_none)
    {
      if (gdbarch_address_class_type_flags_p (gdbarch))
        {
          int type_flags;

          type_flags = gdbarch_address_class_type_flags
                         (gdbarch, byte_size, addr_class);
          gdb_assert ((type_flags & ~TYPE_INSTANCE_FLAG_ADDRESS_CLASS_ALL)
                      == 0);
          type = make_type_with_address_space (type, type_flags);
        }
      else if (TYPE_LENGTH (type) != byte_size)
        {
          complaint (&symfile_complaints, _("invalid pointer size %d"), byte_size);
        }
      else
        {
          /* Should we also complain about unhandled address classes?  */
        }
    }

  TYPE_LENGTH (type) = byte_size;
  return set_die_type (die, type, cu);
}

/* Extract all information from a DW_TAG_ptr_to_member_type DIE and add to
   the user defined type vector.  */

static struct type *
read_tag_ptr_to_member_type (struct die_info *die, struct dwarf2_cu *cu)
{
  struct type *type;
  struct type *to_type;
  struct type *domain;

  to_type = die_type (die, cu);
  domain = die_containing_type (die, cu);

  /* The calls above may have already set the type for this DIE.  */
  type = get_die_type (die, cu);
  if (type)
    return type;

  if (TYPE_CODE (check_typedef (to_type)) == TYPE_CODE_METHOD)
    type = lookup_methodptr_type (to_type);
  else
    type = lookup_memberptr_type (to_type, domain);

  return set_die_type (die, type, cu);
}

/* Extract all information from a DW_TAG_reference_type DIE and add to
   the user defined type vector.  */

static struct type *
read_tag_reference_type (struct die_info *die, struct dwarf2_cu *cu)
{
  struct comp_unit_head *cu_header = &cu->header;
  struct type *type, *target_type;
  struct attribute *attr;

  target_type = die_type (die, cu);

  /* The die_type call above may have already set the type for this DIE.  */
  type = get_die_type (die, cu);
  if (type)
    return type;

  type = lookup_reference_type (target_type);
  attr = dwarf2_attr (die, DW_AT_byte_size, cu);
  if (attr)
    {
      TYPE_LENGTH (type) = DW_UNSND (attr);
    }
  else
    {
      TYPE_LENGTH (type) = cu_header->addr_size;
    }
  return set_die_type (die, type, cu);
}

static struct type *
read_tag_const_type (struct die_info *die, struct dwarf2_cu *cu)
{
  struct type *base_type, *cv_type;

  base_type = die_type (die, cu);

  /* The die_type call above may have already set the type for this DIE.  */
  cv_type = get_die_type (die, cu);
  if (cv_type)
    return cv_type;

  cv_type = make_cv_type (1, TYPE_VOLATILE (base_type), base_type, 0);
  return set_die_type (die, cv_type, cu);
}

static struct type *
read_tag_volatile_type (struct die_info *die, struct dwarf2_cu *cu)
{
  struct type *base_type, *cv_type;

  base_type = die_type (die, cu);

  /* The die_type call above may have already set the type for this DIE.  */
  cv_type = get_die_type (die, cu);
  if (cv_type)
    return cv_type;

  cv_type = make_cv_type (TYPE_CONST (base_type), 1, base_type, 0);
  return set_die_type (die, cv_type, cu);
}

/* Extract all information from a DW_TAG_string_type DIE and add to
   the user defined type vector.  It isn't really a user defined type,
   but it behaves like one, with other DIE's using an AT_user_def_type
   attribute to reference it.  */

static struct type *
read_tag_string_type (struct die_info *die, struct dwarf2_cu *cu)
{
  struct objfile *objfile = cu->objfile;
  struct gdbarch *gdbarch = get_objfile_arch (objfile);
  struct type *type, *range_type, *index_type, *char_type;
  struct attribute *attr;
  unsigned int length;

  attr = dwarf2_attr (die, DW_AT_string_length, cu);
  if (attr)
    {
      length = DW_UNSND (attr);
    }
  else
    {
      /* check for the DW_AT_byte_size attribute */
      attr = dwarf2_attr (die, DW_AT_byte_size, cu);
      if (attr)
        {
          length = DW_UNSND (attr);
        }
      else
        {
          length = 1;
        }
    }

  index_type = objfile_type (objfile)->builtin_int;
  range_type = create_range_type (NULL, index_type, 1, length);
  char_type = language_string_char_type (cu->language_defn, gdbarch);
  type = create_string_type (NULL, char_type, range_type);

  return set_die_type (die, type, cu);
}

/* Handle DIES due to C code like:

   struct foo
   {
   int (*funcp)(int a, long l);
   int b;
   };

   ('funcp' generates a DW_TAG_subroutine_type DIE)
 */

static struct type *
read_subroutine_type (struct die_info *die, struct dwarf2_cu *cu)
{
  struct type *type;            /* Type that this function returns */
  struct type *ftype;           /* Function that returns above type */
  struct attribute *attr;

  type = die_type (die, cu);

  /* The die_type call above may have already set the type for this DIE.  */
  ftype = get_die_type (die, cu);
  if (ftype)
    return ftype;

  ftype = lookup_function_type (type);

  /* All functions in C++, Pascal and Java have prototypes.  */
  attr = dwarf2_attr (die, DW_AT_prototyped, cu);
  if ((attr && (DW_UNSND (attr) != 0))
      || cu->language == language_cplus
      || cu->language == language_java
      || cu->language == language_pascal)
    TYPE_PROTOTYPED (ftype) = 1;
  else if (producer_is_realview (cu->producer))
    /* RealView does not emit DW_AT_prototyped.  We can not
       distinguish prototyped and unprototyped functions; default to
       prototyped, since that is more common in modern code (and
       RealView warns about unprototyped functions).  */
    TYPE_PROTOTYPED (ftype) = 1;

  /* Store the calling convention in the type if it's available in
     the subroutine die.  Otherwise set the calling convention to
     the default value DW_CC_normal.  */
  attr = dwarf2_attr (die, DW_AT_calling_convention, cu);
  TYPE_CALLING_CONVENTION (ftype) = attr ? DW_UNSND (attr) : DW_CC_normal;

  /* We need to add the subroutine type to the die immediately so
     we don't infinitely recurse when dealing with parameters
     declared as the same subroutine type. */
  set_die_type (die, ftype, cu);

  if (die->child != NULL)
    {
      struct type *void_type = objfile_type (cu->objfile)->builtin_void;
      struct die_info *child_die;
      int nparams, iparams;

      /* Count the number of parameters.
         FIXME: GDB currently ignores vararg functions, but knows about
         vararg member functions.  */
      nparams = 0;
      child_die = die->child;
      while (child_die && child_die->tag)
        {
          if (child_die->tag == DW_TAG_formal_parameter)
            nparams++;
          else if (child_die->tag == DW_TAG_unspecified_parameters)
            TYPE_VARARGS (ftype) = 1;
          child_die = sibling_die (child_die);
        }

      /* Allocate storage for parameters and fill them in.  */
      TYPE_NFIELDS (ftype) = nparams;
      TYPE_FIELDS (ftype) = (struct field *)
        TYPE_ZALLOC (ftype, nparams * sizeof (struct field));

      /* TYPE_FIELD_TYPE must never be NULL.  Pre-fill the array to ensure it
         even if we error out during the parameters reading below.  */
      for (iparams = 0; iparams < nparams; iparams++)
        TYPE_FIELD_TYPE (ftype, iparams) = void_type;

      iparams = 0;
      child_die = die->child;
      while (child_die && child_die->tag)
        {
          if (child_die->tag == DW_TAG_formal_parameter)
            {
              /* Dwarf2 has no clean way to discern C++ static and non-static
                 member functions. G++ helps GDB by marking the first
                 parameter for non-static member functions (which is the
                 this pointer) as artificial. We pass this information
                 to dwarf2_add_member_fn via TYPE_FIELD_ARTIFICIAL.  */
              attr = dwarf2_attr (child_die, DW_AT_artificial, cu);
              if (attr)
                TYPE_FIELD_ARTIFICIAL (ftype, iparams) = DW_UNSND (attr);
              else
                {
                  TYPE_FIELD_ARTIFICIAL (ftype, iparams) = 0;

                  /* GCC/43521: In java, the formal parameter
                     "this" is sometimes not marked with DW_AT_artificial.  */
                  if (cu->language == language_java)
                    {
                      const char *name = dwarf2_name (child_die, cu);

                      if (name && !strcmp (name, "this"))
                        TYPE_FIELD_ARTIFICIAL (ftype, iparams) = 1;
                    }
                }
              TYPE_FIELD_TYPE (ftype, iparams) = die_type (child_die, cu);
              iparams++;
            }
          child_die = sibling_die (child_die);
        }
    }

  return ftype;
}

static struct type *
read_typedef (struct die_info *die, struct dwarf2_cu *cu)
{
  struct objfile *objfile = cu->objfile;
  const char *name = NULL;
  struct type *this_type;

  name = dwarf2_full_name (NULL, die, cu);
  this_type = init_type (TYPE_CODE_TYPEDEF, 0,
                         TYPE_FLAG_TARGET_STUB, NULL, objfile);
  TYPE_NAME (this_type) = (char *) name;
  set_die_type (die, this_type, cu);
  TYPE_TARGET_TYPE (this_type) = die_type (die, cu);
  return this_type;
}

/* Find a representation of a given base type and install
   it in the TYPE field of the die.  */

static struct type *
read_base_type (struct die_info *die, struct dwarf2_cu *cu)
{
  struct objfile *objfile = cu->objfile;
  struct type *type;
  struct attribute *attr;
  int encoding = 0, size = 0;
  char *name;
  enum type_code code = TYPE_CODE_INT;
  int type_flags = 0;
  struct type *target_type = NULL;

  attr = dwarf2_attr (die, DW_AT_encoding, cu);
  if (attr)
    {
      encoding = DW_UNSND (attr);
    }
  attr = dwarf2_attr (die, DW_AT_byte_size, cu);
  if (attr)
    {
      size = DW_UNSND (attr);
    }
  name = dwarf2_name (die, cu);
  if (!name)
    {
      complaint (&symfile_complaints,
                 _("DW_AT_name missing from DW_TAG_base_type"));
    }

  switch (encoding)
    {
      case DW_ATE_address:
        /* Turn DW_ATE_address into a void * pointer.  */
        code = TYPE_CODE_PTR;
        type_flags |= TYPE_FLAG_UNSIGNED;
        target_type = init_type (TYPE_CODE_VOID, 1, 0, NULL, objfile);
        break;
      case DW_ATE_boolean:
        code = TYPE_CODE_BOOL;
        type_flags |= TYPE_FLAG_UNSIGNED;
        break;
      case DW_ATE_complex_float:
        code = TYPE_CODE_COMPLEX;
        target_type = init_type (TYPE_CODE_FLT, size / 2, 0, NULL, objfile);
        break;
      case DW_ATE_decimal_float:
        code = TYPE_CODE_DECFLOAT;
        break;
      case DW_ATE_float:
        code = TYPE_CODE_FLT;
        break;
      case DW_ATE_signed:
        break;
      case DW_ATE_unsigned:
        type_flags |= TYPE_FLAG_UNSIGNED;
        break;
      case DW_ATE_signed_char:
        if (cu->language == language_ada || cu->language == language_m2
            || cu->language == language_pascal)
          code = TYPE_CODE_CHAR;
        break;
      case DW_ATE_unsigned_char:
        if (cu->language == language_ada || cu->language == language_m2
            || cu->language == language_pascal)
          code = TYPE_CODE_CHAR;
        type_flags |= TYPE_FLAG_UNSIGNED;
        break;
      case DW_ATE_UTF:
        /* We just treat this as an integer and then recognize the
           type by name elsewhere.  */
        break;

      default:
        complaint (&symfile_complaints, _("unsupported DW_AT_encoding: '%s'"),
                   dwarf_type_encoding_name (encoding));
        break;
    }

  type = init_type (code, size, type_flags, NULL, objfile);
  TYPE_NAME (type) = name;
  TYPE_TARGET_TYPE (type) = target_type;

  if (name && strcmp (name, "char") == 0)
    TYPE_NOSIGN (type) = 1;

  return set_die_type (die, type, cu);
}

/* Read the given DW_AT_subrange DIE.  */

static struct type *
read_subrange_type (struct die_info *die, struct dwarf2_cu *cu)
{
  struct gdbarch *gdbarch = get_objfile_arch (cu->objfile);
  struct type *base_type;
  struct type *range_type;
  struct attribute *attr;
  LONGEST low = 0;
  LONGEST high = -1;
  char *name;
  LONGEST negative_mask;

  base_type = die_type (die, cu);
  /* Preserve BASE_TYPE's original type, just set its LENGTH.  */
  check_typedef (base_type);

  /* The die_type call above may have already set the type for this DIE.  */
  range_type = get_die_type (die, cu);
  if (range_type)
    return range_type;

  if (cu->language == language_fortran)
    {
      /* FORTRAN implies a lower bound of 1, if not given.  */
      low = 1;
    }

  /* FIXME: For variable sized arrays either of these could be
     a variable rather than a constant value.  We'll allow it,
     but we don't know how to handle it.  */
  attr = dwarf2_attr (die, DW_AT_lower_bound, cu);
  if (attr)
    low = dwarf2_get_attr_constant_value (attr, 0);

  attr = dwarf2_attr (die, DW_AT_upper_bound, cu);
  if (attr)
    {
      if (attr->form == DW_FORM_block1 || is_ref_attr (attr))
        {
          /* GCC encodes arrays with unspecified or dynamic length
             with a DW_FORM_block1 attribute or a reference attribute.
             FIXME: GDB does not yet know how to handle dynamic
             arrays properly, treat them as arrays with unspecified
             length for now.

             FIXME: jimb/2003-09-22: GDB does not really know
             how to handle arrays of unspecified length
             either; we just represent them as zero-length
             arrays.  Choose an appropriate upper bound given
             the lower bound we've computed above.  */
          high = low - 1;
        }
      else
        high = dwarf2_get_attr_constant_value (attr, 1);
    }
  else
    {
      attr = dwarf2_attr (die, DW_AT_count, cu);
      if (attr)
        {
          int count = dwarf2_get_attr_constant_value (attr, 1);
          high = low + count - 1;
        }
    }

  /* Dwarf-2 specifications explicitly allows to create subrange types
     without specifying a base type.
     In that case, the base type must be set to the type of
     the lower bound, upper bound or count, in that order, if any of these
     three attributes references an object that has a type.
     If no base type is found, the Dwarf-2 specifications say that
     a signed integer type of size equal to the size of an address should
     be used.
     For the following C code: `extern char gdb_int [];'
     GCC produces an empty range DIE.
     FIXME: muller/2010-05-28: Possible references to object for low bound,
     high bound or count are not yet handled by this code.
  */
  if (TYPE_CODE (base_type) == TYPE_CODE_VOID)
    {
      struct objfile *objfile = cu->objfile;
      struct gdbarch *gdbarch = get_objfile_arch (objfile);
      int addr_size = gdbarch_addr_bit (gdbarch) /8;
      struct type *int_type = objfile_type (objfile)->builtin_int;

      /* Test "int", "long int", and "long long int" objfile types,
         and select the first one having a size above or equal to the
         architecture address size.  */
      if (int_type && TYPE_LENGTH (int_type) >= addr_size)
        base_type = int_type;
      else
        {
          int_type = objfile_type (objfile)->builtin_long;
          if (int_type && TYPE_LENGTH (int_type) >= addr_size)
            base_type = int_type;
          else
            {
              int_type = objfile_type (objfile)->builtin_long_long;
              if (int_type && TYPE_LENGTH (int_type) >= addr_size)
                base_type = int_type;
            }
        }
    }

  negative_mask =
    (LONGEST) -1 << (TYPE_LENGTH (base_type) * TARGET_CHAR_BIT - 1);
  if (!TYPE_UNSIGNED (base_type) && (low & negative_mask))
    low |= negative_mask;
  if (!TYPE_UNSIGNED (base_type) && (high & negative_mask))
    high |= negative_mask;

  range_type = create_range_type (NULL, base_type, low, high);

  /* Mark arrays with dynamic length at least as an array of unspecified
     length.  GDB could check the boundary but before it gets implemented at
     least allow accessing the array elements.  */
  if (attr && attr->form == DW_FORM_block1)
    TYPE_HIGH_BOUND_UNDEFINED (range_type) = 1;

  name = dwarf2_name (die, cu);
  if (name)
    TYPE_NAME (range_type) = name;

  attr = dwarf2_attr (die, DW_AT_byte_size, cu);
  if (attr)
    TYPE_LENGTH (range_type) = DW_UNSND (attr);

  set_die_type (die, range_type, cu);

  /* set_die_type should be already done.  */
  set_descriptive_type (range_type, die, cu);

  return range_type;
}

static struct type *
read_unspecified_type (struct die_info *die, struct dwarf2_cu *cu)
{
  struct type *type;

  /* For now, we only support the C meaning of an unspecified type: void.  */

  type = init_type (TYPE_CODE_VOID, 0, 0, NULL, cu->objfile);
  TYPE_NAME (type) = dwarf2_name (die, cu);

  return set_die_type (die, type, cu);
}

/* Trivial hash function for die_info: the hash value of a DIE
   is its offset in .debug_info for this objfile.  */

static hashval_t
die_hash (const void *item)
{
  const struct die_info *die = item;

  return die->offset;
}

/* Trivial comparison function for die_info structures: two DIEs
   are equal if they have the same offset.  */

static int
die_eq (const void *item_lhs, const void *item_rhs)
{
  const struct die_info *die_lhs = item_lhs;
  const struct die_info *die_rhs = item_rhs;

  return die_lhs->offset == die_rhs->offset;
}

/* Read a whole compilation unit into a linked list of dies.  */

static struct die_info *
read_comp_unit (gdb_byte *info_ptr, struct dwarf2_cu *cu)
{
  struct die_reader_specs reader_specs;

  gdb_assert (cu->die_hash == NULL);
  cu->die_hash
    = htab_create_alloc_ex (cu->header.length / 12,
                            die_hash,
                            die_eq,
                            NULL,
                            &cu->comp_unit_obstack,
                            hashtab_obstack_allocate,
                            dummy_obstack_deallocate);

  init_cu_die_reader (&reader_specs, cu);

  return read_die_and_children (&reader_specs, info_ptr, &info_ptr, NULL);
}

/* Main entry point for reading a DIE and all children.
   Read the DIE and dump it if requested.  */

static struct die_info *
read_die_and_children (const struct die_reader_specs *reader,
                       gdb_byte *info_ptr,
                       gdb_byte **new_info_ptr,
                       struct die_info *parent)
{
  struct die_info *result = read_die_and_children_1 (reader, info_ptr,
                                                     new_info_ptr, parent);

  if (dwarf2_die_debug)
    {
      fprintf_unfiltered (gdb_stdlog,
                          "\nRead die from %s of %s:\n",
                          reader->buffer == dwarf2_per_objfile->info.buffer
                          ? ".debug_info"
                          : reader->buffer == dwarf2_per_objfile->types.buffer
                          ? ".debug_types"
                          : "unknown section",
                          reader->abfd->filename);
      dump_die (result, dwarf2_die_debug);
    }

  return result;
}

/* Read a single die and all its descendents.  Set the die's sibling
   field to NULL; set other fields in the die correctly, and set all
   of the descendents' fields correctly.  Set *NEW_INFO_PTR to the
   location of the info_ptr after reading all of those dies.  PARENT
   is the parent of the die in question.  */

static struct die_info *
read_die_and_children_1 (const struct die_reader_specs *reader,
                         gdb_byte *info_ptr,
                         gdb_byte **new_info_ptr,
                         struct die_info *parent)
{
  struct die_info *die;
  gdb_byte *cur_ptr;
  int has_children;

  cur_ptr = read_full_die (reader, &die, info_ptr, &has_children);
  if (die == NULL)
    {
      *new_info_ptr = cur_ptr;
      return NULL;
    }
  store_in_ref_table (die, reader->cu);

  if (has_children)
    die->child = read_die_and_siblings (reader, cur_ptr, new_info_ptr, die);
  else
    {
      die->child = NULL;
      *new_info_ptr = cur_ptr;
    }

  die->sibling = NULL;
  die->parent = parent;
  return die;
}

/* Read a die, all of its descendents, and all of its siblings; set
   all of the fields of all of the dies correctly.  Arguments are as
   in read_die_and_children.  */

static struct die_info *
read_die_and_siblings (const struct die_reader_specs *reader,
                       gdb_byte *info_ptr,
                       gdb_byte **new_info_ptr,
                       struct die_info *parent)
{
  struct die_info *first_die, *last_sibling;
  gdb_byte *cur_ptr;

  cur_ptr = info_ptr;
  first_die = last_sibling = NULL;

  while (1)
    {
      struct die_info *die
        = read_die_and_children_1 (reader, cur_ptr, &cur_ptr, parent);

      if (die == NULL)
        {
          *new_info_ptr = cur_ptr;
          return first_die;
        }

      if (!first_die)
        first_die = die;
      else
        last_sibling->sibling = die;

      last_sibling = die;
    }
}

/* Read the die from the .debug_info section buffer.  Set DIEP to
   point to a newly allocated die with its information, except for its
   child, sibling, and parent fields.  Set HAS_CHILDREN to tell
   whether the die has children or not.  */

static gdb_byte *
read_full_die (const struct die_reader_specs *reader,
               struct die_info **diep, gdb_byte *info_ptr,
               int *has_children)
{
  unsigned int abbrev_number, bytes_read, i, offset;
  struct abbrev_info *abbrev;
  struct die_info *die;
  struct dwarf2_cu *cu = reader->cu;
  bfd *abfd = reader->abfd;

  offset = info_ptr - reader->buffer;
  abbrev_number = read_unsigned_leb128 (abfd, info_ptr, &bytes_read);
  info_ptr += bytes_read;
  if (!abbrev_number)
    {
      *diep = NULL;
      *has_children = 0;
      return info_ptr;
    }

  abbrev = dwarf2_lookup_abbrev (abbrev_number, cu);
  if (!abbrev)
    error (_("Dwarf Error: could not find abbrev number %d [in module %s]"),
           abbrev_number,
           bfd_get_filename (abfd));

  die = dwarf_alloc_die (cu, abbrev->num_attrs);
  die->offset = offset;
  die->tag = abbrev->tag;
  die->abbrev = abbrev_number;

  die->num_attrs = abbrev->num_attrs;

  for (i = 0; i < abbrev->num_attrs; ++i)
    info_ptr = read_attribute (&die->attrs[i], &abbrev->attrs[i],
                               abfd, info_ptr, cu);

  *diep = die;
  *has_children = abbrev->has_children;
  return info_ptr;
}

/* In DWARF version 2, the description of the debugging information is
   stored in a separate .debug_abbrev section.  Before we read any
   dies from a section we read in all abbreviations and install them
   in a hash table.  This function also sets flags in CU describing
   the data found in the abbrev table.  */

static void
dwarf2_read_abbrevs (bfd *abfd, struct dwarf2_cu *cu)
{
  struct comp_unit_head *cu_header = &cu->header;
  gdb_byte *abbrev_ptr;
  struct abbrev_info *cur_abbrev;
  unsigned int abbrev_number, bytes_read, abbrev_name;
  unsigned int abbrev_form, hash_number;
  struct attr_abbrev *cur_attrs;
  unsigned int allocated_attrs;

  /* Initialize dwarf2 abbrevs */
  obstack_init (&cu->abbrev_obstack);
  cu->dwarf2_abbrevs = obstack_alloc (&cu->abbrev_obstack,
                                      (ABBREV_HASH_SIZE
                                       * sizeof (struct abbrev_info *)));
  memset (cu->dwarf2_abbrevs, 0,
          ABBREV_HASH_SIZE * sizeof (struct abbrev_info *));

  dwarf2_read_section (dwarf2_per_objfile->objfile,
                       &dwarf2_per_objfile->abbrev);
  abbrev_ptr = dwarf2_per_objfile->abbrev.buffer + cu_header->abbrev_offset;
  abbrev_number = read_unsigned_leb128 (abfd, abbrev_ptr, &bytes_read);
  abbrev_ptr += bytes_read;

  allocated_attrs = ATTR_ALLOC_CHUNK;
  cur_attrs = xmalloc (allocated_attrs * sizeof (struct attr_abbrev));

  /* loop until we reach an abbrev number of 0 */
  while (abbrev_number)
    {
      cur_abbrev = dwarf_alloc_abbrev (cu);

      /* read in abbrev header */
      cur_abbrev->number = abbrev_number;
      cur_abbrev->tag = read_unsigned_leb128 (abfd, abbrev_ptr, &bytes_read);
      abbrev_ptr += bytes_read;
      cur_abbrev->has_children = read_1_byte (abfd, abbrev_ptr);
      abbrev_ptr += 1;

      if (cur_abbrev->tag == DW_TAG_namespace)
        cu->has_namespace_info = 1;

      /* now read in declarations */
      abbrev_name = read_unsigned_leb128 (abfd, abbrev_ptr, &bytes_read);
      abbrev_ptr += bytes_read;
      abbrev_form = read_unsigned_leb128 (abfd, abbrev_ptr, &bytes_read);
      abbrev_ptr += bytes_read;
      while (abbrev_name)
        {
          if (cur_abbrev->num_attrs == allocated_attrs)
            {
              allocated_attrs += ATTR_ALLOC_CHUNK;
              cur_attrs
                = xrealloc (cur_attrs, (allocated_attrs
                                        * sizeof (struct attr_abbrev)));
            }

          /* Record whether this compilation unit might have
             inter-compilation-unit references.  If we don't know what form
             this attribute will have, then it might potentially be a
             DW_FORM_ref_addr, so we conservatively expect inter-CU
             references.  */

          if (abbrev_form == DW_FORM_ref_addr
              || abbrev_form == DW_FORM_indirect)
            cu->has_form_ref_addr = 1;

          cur_attrs[cur_abbrev->num_attrs].name = abbrev_name;
          cur_attrs[cur_abbrev->num_attrs++].form = abbrev_form;
          abbrev_name = read_unsigned_leb128 (abfd, abbrev_ptr, &bytes_read);
          abbrev_ptr += bytes_read;
          abbrev_form = read_unsigned_leb128 (abfd, abbrev_ptr, &bytes_read);
          abbrev_ptr += bytes_read;
        }

      cur_abbrev->attrs = obstack_alloc (&cu->abbrev_obstack,
                                         (cur_abbrev->num_attrs
                                          * sizeof (struct attr_abbrev)));
      memcpy (cur_abbrev->attrs, cur_attrs,
              cur_abbrev->num_attrs * sizeof (struct attr_abbrev));

      hash_number = abbrev_number % ABBREV_HASH_SIZE;
      cur_abbrev->next = cu->dwarf2_abbrevs[hash_number];
      cu->dwarf2_abbrevs[hash_number] = cur_abbrev;

      /* Get next abbreviation.
         Under Irix6 the abbreviations for a compilation unit are not
         always properly terminated with an abbrev number of 0.
         Exit loop if we encounter an abbreviation which we have
         already read (which means we are about to read the abbreviations
         for the next compile unit) or if the end of the abbreviation
         table is reached.  */
      if ((unsigned int) (abbrev_ptr - dwarf2_per_objfile->abbrev.buffer)
          >= dwarf2_per_objfile->abbrev.size)
        break;
      abbrev_number = read_unsigned_leb128 (abfd, abbrev_ptr, &bytes_read);
      abbrev_ptr += bytes_read;
      if (dwarf2_lookup_abbrev (abbrev_number, cu) != NULL)
        break;
    }

  xfree (cur_attrs);
}

/* Release the memory used by the abbrev table for a compilation unit.  */

static void
dwarf2_free_abbrev_table (void *ptr_to_cu)
{
  struct dwarf2_cu *cu = ptr_to_cu;

  obstack_free (&cu->abbrev_obstack, NULL);
  cu->dwarf2_abbrevs = NULL;
}

/* Lookup an abbrev_info structure in the abbrev hash table.  */

static struct abbrev_info *
dwarf2_lookup_abbrev (unsigned int number, struct dwarf2_cu *cu)
{
  unsigned int hash_number;
  struct abbrev_info *abbrev;

  hash_number = number % ABBREV_HASH_SIZE;
  abbrev = cu->dwarf2_abbrevs[hash_number];

  while (abbrev)
    {
      if (abbrev->number == number)
        return abbrev;
      else
        abbrev = abbrev->next;
    }
  return NULL;
}

/* Returns nonzero if TAG represents a type that we might generate a partial
   symbol for.  */

static int
is_type_tag_for_partial (int tag)
{
  switch (tag)
    {
#if 0
    /* Some types that would be reasonable to generate partial symbols for,
       that we don't at present.  */
    case DW_TAG_array_type:
    case DW_TAG_file_type:
    case DW_TAG_ptr_to_member_type:
    case DW_TAG_set_type:
    case DW_TAG_string_type:
    case DW_TAG_subroutine_type:
#endif
    case DW_TAG_base_type:
    case DW_TAG_class_type:
    case DW_TAG_interface_type:
    case DW_TAG_enumeration_type:
    case DW_TAG_structure_type:
    case DW_TAG_subrange_type:
    case DW_TAG_typedef:
    case DW_TAG_union_type:
      return 1;
    default:
      return 0;
    }
}

/* Load all DIEs that are interesting for partial symbols into memory.  */

static struct partial_die_info *
load_partial_dies (bfd *abfd, gdb_byte *buffer, gdb_byte *info_ptr,
                   int building_psymtab, struct dwarf2_cu *cu)
{
  struct partial_die_info *part_die;
  struct partial_die_info *parent_die, *last_die, *first_die = NULL;
  struct abbrev_info *abbrev;
  unsigned int bytes_read;
  unsigned int load_all = 0;

  int nesting_level = 1;

  parent_die = NULL;
  last_die = NULL;

  if (cu->per_cu && cu->per_cu->load_all_dies)
    load_all = 1;

  cu->partial_dies
    = htab_create_alloc_ex (cu->header.length / 12,
                            partial_die_hash,
                            partial_die_eq,
                            NULL,
                            &cu->comp_unit_obstack,
                            hashtab_obstack_allocate,
                            dummy_obstack_deallocate);

  part_die = obstack_alloc (&cu->comp_unit_obstack,
                            sizeof (struct partial_die_info));

  while (1)
    {
      abbrev = peek_die_abbrev (info_ptr, &bytes_read, cu);

      /* A NULL abbrev means the end of a series of children.  */
      if (abbrev == NULL)
        {
          if (--nesting_level == 0)
            {
              /* PART_DIE was probably the last thing allocated on the
                 comp_unit_obstack, so we could call obstack_free
                 here.  We don't do that because the waste is small,
                 and will be cleaned up when we're done with this
                 compilation unit.  This way, we're also more robust
                 against other users of the comp_unit_obstack.  */
              return first_die;
            }
          info_ptr += bytes_read;
          last_die = parent_die;
          parent_die = parent_die->die_parent;
          continue;
        }

      /* Check whether this DIE is interesting enough to save.  Normally
         we would not be interested in members here, but there may be
         later variables referencing them via DW_AT_specification (for
         static members).  */
      if (!load_all
          && !is_type_tag_for_partial (abbrev->tag)
          && abbrev->tag != DW_TAG_enumerator
          && abbrev->tag != DW_TAG_subprogram
          && abbrev->tag != DW_TAG_lexical_block
          && abbrev->tag != DW_TAG_variable
          && abbrev->tag != DW_TAG_namespace
          && abbrev->tag != DW_TAG_module
          && abbrev->tag != DW_TAG_member)
        {
          /* Otherwise we skip to the next sibling, if any.  */
          info_ptr = skip_one_die (buffer, info_ptr + bytes_read, abbrev, cu);
          continue;
        }

      info_ptr = read_partial_die (part_die, abbrev, bytes_read, abfd,
                                   buffer, info_ptr, cu);

      /* This two-pass algorithm for processing partial symbols has a
         high cost in cache pressure.  Thus, handle some simple cases
         here which cover the majority of C partial symbols.  DIEs
         which neither have specification tags in them, nor could have
         specification tags elsewhere pointing at them, can simply be
         processed and discarded.

         This segment is also optional; scan_partial_symbols and
         add_partial_symbol will handle these DIEs if we chain
         them in normally.  When compilers which do not emit large
         quantities of duplicate debug information are more common,
         this code can probably be removed.  */

      /* Any complete simple types at the top level (pretty much all
         of them, for a language without namespaces), can be processed
         directly.  */
      if (parent_die == NULL
          && part_die->has_specification == 0
          && part_die->is_declaration == 0
          && (part_die->tag == DW_TAG_typedef
              || part_die->tag == DW_TAG_base_type
              || part_die->tag == DW_TAG_subrange_type))
        {
          if (building_psymtab && part_die->name != NULL)
            add_psymbol_to_list (part_die->name, strlen (part_die->name), 0,
                                 VAR_DOMAIN, LOC_TYPEDEF,
                                 &cu->objfile->static_psymbols,
                                 0, (CORE_ADDR) 0, cu->language, cu->objfile);
          info_ptr = locate_pdi_sibling (part_die, buffer, info_ptr, abfd, cu);
          continue;
        }

      /* If we're at the second level, and we're an enumerator, and
         our parent has no specification (meaning possibly lives in a
         namespace elsewhere), then we can add the partial symbol now
         instead of queueing it.  */
      if (part_die->tag == DW_TAG_enumerator
          && parent_die != NULL
          && parent_die->die_parent == NULL
          && parent_die->tag == DW_TAG_enumeration_type
          && parent_die->has_specification == 0)
        {
          if (part_die->name == NULL)
            complaint (&symfile_complaints, _("malformed enumerator DIE ignored"));
          else if (building_psymtab)
            add_psymbol_to_list (part_die->name, strlen (part_die->name), 0,
                                 VAR_DOMAIN, LOC_CONST,
                                 (cu->language == language_cplus
                                  || cu->language == language_java)
                                 ? &cu->objfile->global_psymbols
                                 : &cu->objfile->static_psymbols,
                                 0, (CORE_ADDR) 0, cu->language, cu->objfile);

          info_ptr = locate_pdi_sibling (part_die, buffer, info_ptr, abfd, cu);
          continue;
        }

      /* We'll save this DIE so link it in.  */
      part_die->die_parent = parent_die;
      part_die->die_sibling = NULL;
      part_die->die_child = NULL;

      if (last_die && last_die == parent_die)
        last_die->die_child = part_die;
      else if (last_die)
        last_die->die_sibling = part_die;

      last_die = part_die;

      if (first_die == NULL)
        first_die = part_die;

      /* Maybe add the DIE to the hash table.  Not all DIEs that we
         find interesting need to be in the hash table, because we
         also have the parent/sibling/child chains; only those that we
         might refer to by offset later during partial symbol reading.

         For now this means things that might have be the target of a
         DW_AT_specification, DW_AT_abstract_origin, or
         DW_AT_extension.  DW_AT_extension will refer only to
         namespaces; DW_AT_abstract_origin refers to functions (and
         many things under the function DIE, but we do not recurse
         into function DIEs during partial symbol reading) and
         possibly variables as well; DW_AT_specification refers to
         declarations.  Declarations ought to have the DW_AT_declaration
         flag.  It happens that GCC forgets to put it in sometimes, but
         only for functions, not for types.

         Adding more things than necessary to the hash table is harmless
         except for the performance cost.  Adding too few will result in
         wasted time in find_partial_die, when we reread the compilation
         unit with load_all_dies set.  */

      if (load_all
          || abbrev->tag == DW_TAG_subprogram
          || abbrev->tag == DW_TAG_variable
          || abbrev->tag == DW_TAG_namespace
          || part_die->is_declaration)
        {
          void **slot;

          slot = htab_find_slot_with_hash (cu->partial_dies, part_die,
                                           part_die->offset, INSERT);
          *slot = part_die;
        }

      part_die = obstack_alloc (&cu->comp_unit_obstack,
                                sizeof (struct partial_die_info));

      /* For some DIEs we want to follow their children (if any).  For C
         we have no reason to follow the children of structures; for other
         languages we have to, both so that we can get at method physnames
         to infer fully qualified class names, and for DW_AT_specification.

         For Ada, we need to scan the children of subprograms and lexical
         blocks as well because Ada allows the definition of nested
         entities that could be interesting for the debugger, such as
         nested subprograms for instance.  */
      if (last_die->has_children
          && (load_all
              || last_die->tag == DW_TAG_namespace
              || last_die->tag == DW_TAG_module
              || last_die->tag == DW_TAG_enumeration_type
              || (cu->language != language_c
                  && (last_die->tag == DW_TAG_class_type
                      || last_die->tag == DW_TAG_interface_type
                      || last_die->tag == DW_TAG_structure_type
                      || last_die->tag == DW_TAG_union_type))
              || (cu->language == language_ada
                  && (last_die->tag == DW_TAG_subprogram
                      || last_die->tag == DW_TAG_lexical_block))))
        {
          nesting_level++;
          parent_die = last_die;
          continue;
        }

      /* Otherwise we skip to the next sibling, if any.  */
      info_ptr = locate_pdi_sibling (last_die, buffer, info_ptr, abfd, cu);

      /* Back to the top, do it again.  */
    }
}

/* Read a minimal amount of information into the minimal die structure.  */

static gdb_byte *
read_partial_die (struct partial_die_info *part_die,
                  struct abbrev_info *abbrev,
                  unsigned int abbrev_len, bfd *abfd,
                  gdb_byte *buffer, gdb_byte *info_ptr,
                  struct dwarf2_cu *cu)
{
  unsigned int i;
  struct attribute attr;
  int has_low_pc_attr = 0;
  int has_high_pc_attr = 0;

  memset (part_die, 0, sizeof (struct partial_die_info));

  part_die->offset = info_ptr - buffer;

  info_ptr += abbrev_len;

  if (abbrev == NULL)
    return info_ptr;

  part_die->tag = abbrev->tag;
  part_die->has_children = abbrev->has_children;

  for (i = 0; i < abbrev->num_attrs; ++i)
    {
      info_ptr = read_attribute (&attr, &abbrev->attrs[i], abfd, info_ptr, cu);

      /* Store the data if it is of an attribute we want to keep in a
         partial symbol table.  */
      switch (attr.name)
        {
        case DW_AT_name:
          switch (part_die->tag)
            {
            case DW_TAG_compile_unit:
            case DW_TAG_type_unit:
              /* Compilation units have a DW_AT_name that is a filename, not
                 a source language identifier.  */
            case DW_TAG_enumeration_type:
            case DW_TAG_enumerator:
              /* These tags always have simple identifiers already; no need
                 to canonicalize them.  */
              part_die->name = DW_STRING (&attr);
              break;
            default:
              part_die->name
                = dwarf2_canonicalize_name (DW_STRING (&attr), cu,
                                            &cu->objfile->objfile_obstack);
              break;
            }
          break;
        case DW_AT_linkage_name:
        case DW_AT_MIPS_linkage_name:
          /* Note that both forms of linkage name might appear.  We
             assume they will be the same, and we only store the last
             one we see.  */
          if (cu->language == language_ada)
            part_die->name = DW_STRING (&attr);
          break;
        case DW_AT_low_pc:
          has_low_pc_attr = 1;
          part_die->lowpc = DW_ADDR (&attr);
          break;
        case DW_AT_high_pc:
          has_high_pc_attr = 1;
          part_die->highpc = DW_ADDR (&attr);
          break;
        case DW_AT_location:
          /* Support the .debug_loc offsets */
          if (attr_form_is_block (&attr))
            {
               part_die->locdesc = DW_BLOCK (&attr);
            }
          else if (attr_form_is_section_offset (&attr))
            {
              dwarf2_complex_location_expr_complaint ();
            }
          else
            {
              dwarf2_invalid_attrib_class_complaint ("DW_AT_location",
                                                     "partial symbol information");
            }
          break;
        case DW_AT_external:
          part_die->is_external = DW_UNSND (&attr);
          break;
        case DW_AT_declaration:
          part_die->is_declaration = DW_UNSND (&attr);
          break;
        case DW_AT_type:
          part_die->has_type = 1;
          break;
        case DW_AT_abstract_origin:
        case DW_AT_specification:
        case DW_AT_extension:
          part_die->has_specification = 1;
          part_die->spec_offset = dwarf2_get_ref_die_offset (&attr);
          break;
        case DW_AT_sibling:
          /* Ignore absolute siblings, they might point outside of
             the current compile unit.  */
          if (attr.form == DW_FORM_ref_addr)
            complaint (&symfile_complaints, _("ignoring absolute DW_AT_sibling"));
          else
            part_die->sibling = buffer + dwarf2_get_ref_die_offset (&attr);
          break;
        case DW_AT_byte_size:
          part_die->has_byte_size = 1;
          break;
        case DW_AT_calling_convention:
          /* DWARF doesn't provide a way to identify a program's source-level
             entry point.  DW_AT_calling_convention attributes are only meant
             to describe functions' calling conventions.

             However, because it's a necessary piece of information in
             Fortran, and because DW_CC_program is the only piece of debugging
             information whose definition refers to a 'main program' at all,
             several compilers have begun marking Fortran main programs with
             DW_CC_program --- even when those functions use the standard
             calling conventions.

             So until DWARF specifies a way to provide this information and
             compilers pick up the new representation, we'll support this
             practice.  */
          if (DW_UNSND (&attr) == DW_CC_program
              && cu->language == language_fortran)
            set_main_name (part_die->name);
          break;
        default:
          break;
        }
    }

  /* When using the GNU linker, .gnu.linkonce. sections are used to
     eliminate duplicate copies of functions and vtables and such.
     The linker will arbitrarily choose one and discard the others.
     The AT_*_pc values for such functions refer to local labels in
     these sections.  If the section from that file was discarded, the
     labels are not in the output, so the relocs get a value of 0.
     If this is a discarded function, mark the pc bounds as invalid,
     so that GDB will ignore it.  */
  if (has_low_pc_attr && has_high_pc_attr
      && part_die->lowpc < part_die->highpc
      && (part_die->lowpc != 0
          || dwarf2_per_objfile->has_section_at_zero))
    part_die->has_pc_info = 1;

  return info_ptr;
}

/* Find a cached partial DIE at OFFSET in CU.  */

static struct partial_die_info *
find_partial_die_in_comp_unit (unsigned int offset, struct dwarf2_cu *cu)
{
  struct partial_die_info *lookup_die = NULL;
  struct partial_die_info part_die;

  part_die.offset = offset;
  lookup_die = htab_find_with_hash (cu->partial_dies, &part_die, offset);

  return lookup_die;
}

/* Find a partial DIE at OFFSET, which may or may not be in CU,
   except in the case of .debug_types DIEs which do not reference
   outside their CU (they do however referencing other types via
   DW_FORM_sig8).  */

static struct partial_die_info *
find_partial_die (unsigned int offset, struct dwarf2_cu *cu)
{
  struct dwarf2_per_cu_data *per_cu = NULL;
  struct partial_die_info *pd = NULL;

  if (cu->per_cu->from_debug_types)
    {
      pd = find_partial_die_in_comp_unit (offset, cu);
      if (pd != NULL)
        return pd;
      goto not_found;
    }

  if (offset_in_cu_p (&cu->header, offset))
    {
      pd = find_partial_die_in_comp_unit (offset, cu);
      if (pd != NULL)
        return pd;
    }

  per_cu = dwarf2_find_containing_comp_unit (offset, cu->objfile);

  if (per_cu->cu == NULL)
    {
      load_partial_comp_unit (per_cu, cu->objfile);
      per_cu->cu->read_in_chain = dwarf2_per_objfile->read_in_chain;
      dwarf2_per_objfile->read_in_chain = per_cu;
    }

  per_cu->cu->last_used = 0;
  pd = find_partial_die_in_comp_unit (offset, per_cu->cu);

  if (pd == NULL && per_cu->load_all_dies == 0)
    {
      struct cleanup *back_to;
      struct partial_die_info comp_unit_die;
      struct abbrev_info *abbrev;
      unsigned int bytes_read;
      char *info_ptr;

      per_cu->load_all_dies = 1;

      /* Re-read the DIEs.  */
      back_to = make_cleanup (null_cleanup, 0);
      if (per_cu->cu->dwarf2_abbrevs == NULL)
        {
          dwarf2_read_abbrevs (per_cu->cu->objfile->obfd, per_cu->cu);
          make_cleanup (dwarf2_free_abbrev_table, per_cu->cu);
        }
      info_ptr = (dwarf2_per_objfile->info.buffer
                  + per_cu->cu->header.offset
                  + per_cu->cu->header.first_die_offset);
      abbrev = peek_die_abbrev (info_ptr, &bytes_read, per_cu->cu);
      info_ptr = read_partial_die (&comp_unit_die, abbrev, bytes_read,
                                   per_cu->cu->objfile->obfd,
                                   dwarf2_per_objfile->info.buffer, info_ptr,
                                   per_cu->cu);
      if (comp_unit_die.has_children)
        load_partial_dies (per_cu->cu->objfile->obfd,
                           dwarf2_per_objfile->info.buffer, info_ptr,
                           0, per_cu->cu);
      do_cleanups (back_to);

      pd = find_partial_die_in_comp_unit (offset, per_cu->cu);
    }

 not_found:

  if (pd == NULL)
    internal_error (__FILE__, __LINE__,
                    _("could not find partial DIE 0x%x in cache [from module %s]\n"),
                    offset, bfd_get_filename (cu->objfile->obfd));
  return pd;
}

/* Adjust PART_DIE before generating a symbol for it.  This function
   may set the is_external flag or change the DIE's name.  */

static void
fixup_partial_die (struct partial_die_info *part_die,
                   struct dwarf2_cu *cu)
{
  /* If we found a reference attribute and the DIE has no name, try
     to find a name in the referred to DIE.  */

  if (part_die->name == NULL && part_die->has_specification)
    {
      struct partial_die_info *spec_die;

      spec_die = find_partial_die (part_die->spec_offset, cu);

      fixup_partial_die (spec_die, cu);

      if (spec_die->name)
        {
          part_die->name = spec_die->name;

          /* Copy DW_AT_external attribute if it is set.  */
          if (spec_die->is_external)
            part_die->is_external = spec_die->is_external;
        }
    }

  /* Set default names for some unnamed DIEs.  */
  if (part_die->name == NULL && (part_die->tag == DW_TAG_structure_type
                                 || part_die->tag == DW_TAG_class_type))
    part_die->name = "(anonymous class)";

  if (part_die->name == NULL && part_die->tag == DW_TAG_namespace)
    part_die->name = "(anonymous namespace)";

  if (part_die->tag == DW_TAG_structure_type
      || part_die->tag == DW_TAG_class_type
      || part_die->tag == DW_TAG_union_type)
    guess_structure_name (part_die, cu);
}

/* Read an attribute value described by an attribute form.  */

static gdb_byte *
read_attribute_value (struct attribute *attr, unsigned form,
                      bfd *abfd, gdb_byte *info_ptr,
                      struct dwarf2_cu *cu)
{
  struct comp_unit_head *cu_header = &cu->header;
  unsigned int bytes_read;
  struct dwarf_block *blk;

  attr->form = form;
  switch (form)
    {
    case DW_FORM_ref_addr:
      if (cu->header.version == 2)
        DW_ADDR (attr) = read_address (abfd, info_ptr, cu, &bytes_read);
      else
        DW_ADDR (attr) = read_offset (abfd, info_ptr, &cu->header, &bytes_read);
      info_ptr += bytes_read;
      break;
    case DW_FORM_addr:
      DW_ADDR (attr) = read_address (abfd, info_ptr, cu, &bytes_read);
      info_ptr += bytes_read;
      break;
    case DW_FORM_block2:
      blk = dwarf_alloc_block (cu);
      blk->size = read_2_bytes (abfd, info_ptr);
      info_ptr += 2;
      blk->data = read_n_bytes (abfd, info_ptr, blk->size);
      info_ptr += blk->size;
      DW_BLOCK (attr) = blk;
      break;
    case DW_FORM_block4:
      blk = dwarf_alloc_block (cu);
      blk->size = read_4_bytes (abfd, info_ptr);
      info_ptr += 4;
      blk->data = read_n_bytes (abfd, info_ptr, blk->size);
      info_ptr += blk->size;
      DW_BLOCK (attr) = blk;
      break;
    case DW_FORM_data2:
      DW_UNSND (attr) = read_2_bytes (abfd, info_ptr);
      info_ptr += 2;
      break;
    case DW_FORM_data4:
      DW_UNSND (attr) = read_4_bytes (abfd, info_ptr);
      info_ptr += 4;
      break;
    case DW_FORM_data8:
      DW_UNSND (attr) = read_8_bytes (abfd, info_ptr);
      info_ptr += 8;
      break;
    case DW_FORM_sec_offset:
      DW_UNSND (attr) = read_offset (abfd, info_ptr, &cu->header, &bytes_read);
      info_ptr += bytes_read;
      break;
    case DW_FORM_string:
      DW_STRING (attr) = read_string (abfd, info_ptr, &bytes_read);
      DW_STRING_IS_CANONICAL (attr) = 0;
      info_ptr += bytes_read;
      break;
    case DW_FORM_strp:
      DW_STRING (attr) = read_indirect_string (abfd, info_ptr, cu_header,
                                               &bytes_read);
      DW_STRING_IS_CANONICAL (attr) = 0;
      info_ptr += bytes_read;
      break;
    case DW_FORM_exprloc:
    case DW_FORM_block:
      blk = dwarf_alloc_block (cu);
      blk->size = read_unsigned_leb128 (abfd, info_ptr, &bytes_read);
      info_ptr += bytes_read;
      blk->data = read_n_bytes (abfd, info_ptr, blk->size);
      info_ptr += blk->size;
      DW_BLOCK (attr) = blk;
      break;
    case DW_FORM_block1:
      blk = dwarf_alloc_block (cu);
      blk->size = read_1_byte (abfd, info_ptr);
      info_ptr += 1;
      blk->data = read_n_bytes (abfd, info_ptr, blk->size);
      info_ptr += blk->size;
      DW_BLOCK (attr) = blk;
      break;
    case DW_FORM_data1:
      DW_UNSND (attr) = read_1_byte (abfd, info_ptr);
      info_ptr += 1;
      break;
    case DW_FORM_flag:
      DW_UNSND (attr) = read_1_byte (abfd, info_ptr);
      info_ptr += 1;
      break;
    case DW_FORM_flag_present:
      DW_UNSND (attr) = 1;
      break;
    case DW_FORM_sdata:
      DW_SND (attr) = read_signed_leb128 (abfd, info_ptr, &bytes_read);
      info_ptr += bytes_read;
      break;
    case DW_FORM_udata:
      DW_UNSND (attr) = read_unsigned_leb128 (abfd, info_ptr, &bytes_read);
      info_ptr += bytes_read;
      break;
    case DW_FORM_ref1:
      DW_ADDR (attr) = cu->header.offset + read_1_byte (abfd, info_ptr);
      info_ptr += 1;
      break;
    case DW_FORM_ref2:
      DW_ADDR (attr) = cu->header.offset + read_2_bytes (abfd, info_ptr);
      info_ptr += 2;
      break;
    case DW_FORM_ref4:
      DW_ADDR (attr) = cu->header.offset + read_4_bytes (abfd, info_ptr);
      info_ptr += 4;
      break;
    case DW_FORM_ref8:
      DW_ADDR (attr) = cu->header.offset + read_8_bytes (abfd, info_ptr);
      info_ptr += 8;
      break;
    case DW_FORM_sig8:
      /* Convert the signature to something we can record in DW_UNSND
         for later lookup.
         NOTE: This is NULL if the type wasn't found.  */
      DW_SIGNATURED_TYPE (attr) =
        lookup_signatured_type (cu->objfile, read_8_bytes (abfd, info_ptr));
      info_ptr += 8;
      break;
    case DW_FORM_ref_udata:
      DW_ADDR (attr) = (cu->header.offset
                        + read_unsigned_leb128 (abfd, info_ptr, &bytes_read));
      info_ptr += bytes_read;
      break;
    case DW_FORM_indirect:
      form = read_unsigned_leb128 (abfd, info_ptr, &bytes_read);
      info_ptr += bytes_read;
      info_ptr = read_attribute_value (attr, form, abfd, info_ptr, cu);
      break;
    default:
      error (_("Dwarf Error: Cannot handle %s in DWARF reader [in module %s]"),
             dwarf_form_name (form),
             bfd_get_filename (abfd));
    }

  /* We have seen instances where the compiler tried to emit a byte
     size attribute of -1 which ended up being encoded as an unsigned
     0xffffffff.  Although 0xffffffff is technically a valid size value,
     an object of this size seems pretty unlikely so we can relatively
     safely treat these cases as if the size attribute was invalid and
     treat them as zero by default.  */
  if (attr->name == DW_AT_byte_size
      && form == DW_FORM_data4
      && DW_UNSND (attr) >= 0xffffffff)
    {
      complaint
        (&symfile_complaints,
         _("Suspicious DW_AT_byte_size value treated as zero instead of %s"),
         hex_string (DW_UNSND (attr)));
      DW_UNSND (attr) = 0;
    }

  return info_ptr;
}

/* Read an attribute described by an abbreviated attribute.  */

static gdb_byte *
read_attribute (struct attribute *attr, struct attr_abbrev *abbrev,
                bfd *abfd, gdb_byte *info_ptr, struct dwarf2_cu *cu)
{
  attr->name = abbrev->name;
  return read_attribute_value (attr, abbrev->form, abfd, info_ptr, cu);
}

/* read dwarf information from a buffer */

static unsigned int
read_1_byte (bfd *abfd, gdb_byte *buf)
{
  return bfd_get_8 (abfd, buf);
}

static int
read_1_signed_byte (bfd *abfd, gdb_byte *buf)
{
  return bfd_get_signed_8 (abfd, buf);
}

static unsigned int
read_2_bytes (bfd *abfd, gdb_byte *buf)
{
  return bfd_get_16 (abfd, buf);
}

static int
read_2_signed_bytes (bfd *abfd, gdb_byte *buf)
{
  return bfd_get_signed_16 (abfd, buf);
}

static unsigned int
read_4_bytes (bfd *abfd, gdb_byte *buf)
{
  return bfd_get_32 (abfd, buf);
}

static int
read_4_signed_bytes (bfd *abfd, gdb_byte *buf)
{
  return bfd_get_signed_32 (abfd, buf);
}

static ULONGEST
read_8_bytes (bfd *abfd, gdb_byte *buf)
{
  return bfd_get_64 (abfd, buf);
}

static CORE_ADDR
read_address (bfd *abfd, gdb_byte *buf, struct dwarf2_cu *cu,
              unsigned int *bytes_read)
{
  struct comp_unit_head *cu_header = &cu->header;
  CORE_ADDR retval = 0;

  if (cu_header->signed_addr_p)
    {
      switch (cu_header->addr_size)
        {
        case 2:
          retval = bfd_get_signed_16 (abfd, buf);
          break;
        case 4:
          retval = bfd_get_signed_32 (abfd, buf);
          break;
        case 8:
          retval = bfd_get_signed_64 (abfd, buf);
          break;
        default:
          internal_error (__FILE__, __LINE__,
                          _("read_address: bad switch, signed [in module %s]"),
                          bfd_get_filename (abfd));
        }
    }
  else
    {
      switch (cu_header->addr_size)
        {
        case 2:
          retval = bfd_get_16 (abfd, buf);
          break;
        case 4:
          retval = bfd_get_32 (abfd, buf);
          break;
        case 8:
          retval = bfd_get_64 (abfd, buf);
          break;
        default:
          internal_error (__FILE__, __LINE__,
                          _("read_address: bad switch, unsigned [in module %s]"),
                          bfd_get_filename (abfd));
        }
    }

  *bytes_read = cu_header->addr_size;
  return retval;
}

/* Read the initial length from a section.  The (draft) DWARF 3
   specification allows the initial length to take up either 4 bytes
   or 12 bytes.  If the first 4 bytes are 0xffffffff, then the next 8
   bytes describe the length and all offsets will be 8 bytes in length
   instead of 4.

   An older, non-standard 64-bit format is also handled by this
   function.  The older format in question stores the initial length
   as an 8-byte quantity without an escape value.  Lengths greater
   than 2^32 aren't very common which means that the initial 4 bytes
   is almost always zero.  Since a length value of zero doesn't make
   sense for the 32-bit format, this initial zero can be considered to
   be an escape value which indicates the presence of the older 64-bit
   format.  As written, the code can't detect (old format) lengths
   greater than 4GB.  If it becomes necessary to handle lengths
   somewhat larger than 4GB, we could allow other small values (such
   as the non-sensical values of 1, 2, and 3) to also be used as
   escape values indicating the presence of the old format.

   The value returned via bytes_read should be used to increment the
   relevant pointer after calling read_initial_length().

   [ Note:  read_initial_length() and read_offset() are based on the
     document entitled "DWARF Debugging Information Format", revision
     3, draft 8, dated November 19, 2001.  This document was obtained
     from:

        http://reality.sgiweb.org/davea/dwarf3-draft8-011125.pdf

     This document is only a draft and is subject to change.  (So beware.)

     Details regarding the older, non-standard 64-bit format were
     determined empirically by examining 64-bit ELF files produced by
     the SGI toolchain on an IRIX 6.5 machine.

     - Kevin, July 16, 2002
   ] */

static LONGEST
read_initial_length (bfd *abfd, gdb_byte *buf, unsigned int *bytes_read)
{
  LONGEST length = bfd_get_32 (abfd, buf);

  if (length == 0xffffffff)
    {
      length = bfd_get_64 (abfd, buf + 4);
      *bytes_read = 12;
    }
  else if (length == 0)
    {
      /* Handle the (non-standard) 64-bit DWARF2 format used by IRIX.  */
      length = bfd_get_64 (abfd, buf);
      *bytes_read = 8;
    }
  else
    {
      *bytes_read = 4;
    }

  return length;
}

/* Cover function for read_initial_length.
   Returns the length of the object at BUF, and stores the size of the
   initial length in *BYTES_READ and stores the size that offsets will be in
   *OFFSET_SIZE.
   If the initial length size is not equivalent to that specified in
   CU_HEADER then issue a complaint.
   This is useful when reading non-comp-unit headers.  */

static LONGEST
read_checked_initial_length_and_offset (bfd *abfd, gdb_byte *buf,
                                        const struct comp_unit_head *cu_header,
                                        unsigned int *bytes_read,
                                        unsigned int *offset_size)
{
  LONGEST length = read_initial_length (abfd, buf, bytes_read);

  gdb_assert (cu_header->initial_length_size == 4
              || cu_header->initial_length_size == 8
              || cu_header->initial_length_size == 12);

  if (cu_header->initial_length_size != *bytes_read)
    complaint (&symfile_complaints,
               _("intermixed 32-bit and 64-bit DWARF sections"));

  *offset_size = (*bytes_read == 4) ? 4 : 8;
  return length;
}

/* Read an offset from the data stream.  The size of the offset is
   given by cu_header->offset_size.  */

static LONGEST
read_offset (bfd *abfd, gdb_byte *buf, const struct comp_unit_head *cu_header,
             unsigned int *bytes_read)
{
  LONGEST offset = read_offset_1 (abfd, buf, cu_header->offset_size);

  *bytes_read = cu_header->offset_size;
  return offset;
}

/* Read an offset from the data stream.  */

static LONGEST
read_offset_1 (bfd *abfd, gdb_byte *buf, unsigned int offset_size)
{
  LONGEST retval = 0;

  switch (offset_size)
    {
    case 4:
      retval = bfd_get_32 (abfd, buf);
      break;
    case 8:
      retval = bfd_get_64 (abfd, buf);
      break;
    default:
      internal_error (__FILE__, __LINE__,
                      _("read_offset_1: bad switch [in module %s]"),
                      bfd_get_filename (abfd));
    }

  return retval;
}

static gdb_byte *
read_n_bytes (bfd *abfd, gdb_byte *buf, unsigned int size)
{
  /* If the size of a host char is 8 bits, we can return a pointer
     to the buffer, otherwise we have to copy the data to a buffer
     allocated on the temporary obstack.  */
  gdb_assert (HOST_CHAR_BIT == 8);
  return buf;
}

static char *
read_string (bfd *abfd, gdb_byte *buf, unsigned int *bytes_read_ptr)
{
  /* If the size of a host char is 8 bits, we can return a pointer
     to the string, otherwise we have to copy the string to a buffer
     allocated on the temporary obstack.  */
  gdb_assert (HOST_CHAR_BIT == 8);
  if (*buf == '\0')
    {
      *bytes_read_ptr = 1;
      return NULL;
    }
  *bytes_read_ptr = strlen ((char *) buf) + 1;
  return (char *) buf;
}

static char *
read_indirect_string (bfd *abfd, gdb_byte *buf,
                      const struct comp_unit_head *cu_header,
                      unsigned int *bytes_read_ptr)
{
  LONGEST str_offset = read_offset (abfd, buf, cu_header, bytes_read_ptr);

  dwarf2_read_section (dwarf2_per_objfile->objfile, &dwarf2_per_objfile->str);
  if (dwarf2_per_objfile->str.buffer == NULL)
    {
      error (_("DW_FORM_strp used without .debug_str section [in module %s]"),
                      bfd_get_filename (abfd));
      return NULL;
    }
  if (str_offset >= dwarf2_per_objfile->str.size)
    {
      error (_("DW_FORM_strp pointing outside of .debug_str section [in module %s]"),
                      bfd_get_filename (abfd));
      return NULL;
    }
  gdb_assert (HOST_CHAR_BIT == 8);
  if (dwarf2_per_objfile->str.buffer[str_offset] == '\0')
    return NULL;
  return (char *) (dwarf2_per_objfile->str.buffer + str_offset);
}

static unsigned long
read_unsigned_leb128 (bfd *abfd, gdb_byte *buf, unsigned int *bytes_read_ptr)
{
  unsigned long result;
  unsigned int num_read;
  int i, shift;
  unsigned char byte;

  result = 0;
  shift = 0;
  num_read = 0;
  i = 0;
  while (1)
    {
      byte = bfd_get_8 (abfd, buf);
      buf++;
      num_read++;
      result |= ((unsigned long)(byte & 127) << shift);
      if ((byte & 128) == 0)
        {
          break;
        }
      shift += 7;
    }
  *bytes_read_ptr = num_read;
  return result;
}

static long
read_signed_leb128 (bfd *abfd, gdb_byte *buf, unsigned int *bytes_read_ptr)
{
  long result;
  int i, shift, num_read;
  unsigned char byte;

  result = 0;
  shift = 0;
  num_read = 0;
  i = 0;
  while (1)
    {
      byte = bfd_get_8 (abfd, buf);
      buf++;
      num_read++;
      result |= ((long)(byte & 127) << shift);
      shift += 7;
      if ((byte & 128) == 0)
        {
          break;
        }
    }
  if ((shift < 8 * sizeof (result)) && (byte & 0x40))
    result |= -(((long)1) << shift);
  *bytes_read_ptr = num_read;
  return result;
}

/* Return a pointer to just past the end of an LEB128 number in BUF.  */

static gdb_byte *
skip_leb128 (bfd *abfd, gdb_byte *buf)
{
  int byte;

  while (1)
    {
      byte = bfd_get_8 (abfd, buf);
      buf++;
      if ((byte & 128) == 0)
        return buf;
    }
}

static void
set_cu_language (unsigned int lang, struct dwarf2_cu *cu)
{
  switch (lang)
    {
    case DW_LANG_C89:
    case DW_LANG_C99:
    case DW_LANG_C:
      cu->language = language_c;
      break;
    case DW_LANG_C_plus_plus:
      cu->language = language_cplus;
      break;
    case DW_LANG_D:
      cu->language = language_d;
      break;
    case DW_LANG_Fortran77:
    case DW_LANG_Fortran90:
    case DW_LANG_Fortran95:
      cu->language = language_fortran;
      break;
    case DW_LANG_Mips_Assembler:
      cu->language = language_asm;
      break;
    case DW_LANG_Java:
      cu->language = language_java;
      break;
    case DW_LANG_Ada83:
    case DW_LANG_Ada95:
      cu->language = language_ada;
      break;
    case DW_LANG_Modula2:
      cu->language = language_m2;
      break;
    case DW_LANG_Pascal83:
      cu->language = language_pascal;
      break;
    case DW_LANG_ObjC:
      cu->language = language_objc;
      break;
    case DW_LANG_Cobol74:
    case DW_LANG_Cobol85:
    default:
      cu->language = language_minimal;
      break;
    }
  cu->language_defn = language_def (cu->language);
}

/* Return the named attribute or NULL if not there.  */

static struct attribute *
dwarf2_attr (struct die_info *die, unsigned int name, struct dwarf2_cu *cu)
{
  unsigned int i;
  struct attribute *spec = NULL;

  for (i = 0; i < die->num_attrs; ++i)
    {
      if (die->attrs[i].name == name)
        return &die->attrs[i];
      if (die->attrs[i].name == DW_AT_specification
          || die->attrs[i].name == DW_AT_abstract_origin)
        spec = &die->attrs[i];
    }

  if (spec)
    {
      die = follow_die_ref (die, spec, &cu);
      return dwarf2_attr (die, name, cu);
    }

  return NULL;
}

/* Return the named attribute or NULL if not there,
   but do not follow DW_AT_specification, etc.
   This is for use in contexts where we're reading .debug_types dies.
   Following DW_AT_specification, DW_AT_abstract_origin will take us
   back up the chain, and we want to go down.  */

static struct attribute *
dwarf2_attr_no_follow (struct die_info *die, unsigned int name,
                       struct dwarf2_cu *cu)
{
  unsigned int i;

  for (i = 0; i < die->num_attrs; ++i)
    if (die->attrs[i].name == name)
      return &die->attrs[i];

  return NULL;
}

/* Return non-zero iff the attribute NAME is defined for the given DIE,
   and holds a non-zero value.  This function should only be used for
   DW_FORM_flag or DW_FORM_flag_present attributes.  */

static int
dwarf2_flag_true_p (struct die_info *die, unsigned name, struct dwarf2_cu *cu)
{
  struct attribute *attr = dwarf2_attr (die, name, cu);

  return (attr && DW_UNSND (attr));
}

static int
die_is_declaration (struct die_info *die, struct dwarf2_cu *cu)
{
  /* A DIE is a declaration if it has a DW_AT_declaration attribute
     which value is non-zero.  However, we have to be careful with
     DIEs having a DW_AT_specification attribute, because dwarf2_attr()
     (via dwarf2_flag_true_p) follows this attribute.  So we may
     end up accidently finding a declaration attribute that belongs
     to a different DIE referenced by the specification attribute,
     even though the given DIE does not have a declaration attribute.  */
  return (dwarf2_flag_true_p (die, DW_AT_declaration, cu)
          && dwarf2_attr (die, DW_AT_specification, cu) == NULL);
}

/* Return the die giving the specification for DIE, if there is
   one.  *SPEC_CU is the CU containing DIE on input, and the CU
   containing the return value on output.  If there is no
   specification, but there is an abstract origin, that is
   returned.  */

static struct die_info *
die_specification (struct die_info *die, struct dwarf2_cu **spec_cu)
{
  struct attribute *spec_attr = dwarf2_attr (die, DW_AT_specification,
                                             *spec_cu);

  if (spec_attr == NULL)
    spec_attr = dwarf2_attr (die, DW_AT_abstract_origin, *spec_cu);

  if (spec_attr == NULL)
    return NULL;
  else
    return follow_die_ref (die, spec_attr, spec_cu);
}

/* Free the line_header structure *LH, and any arrays and strings it
   refers to.  */
static void
free_line_header (struct line_header *lh)
{
  if (lh->standard_opcode_lengths)
    xfree (lh->standard_opcode_lengths);

  /* Remember that all the lh->file_names[i].name pointers are
     pointers into debug_line_buffer, and don't need to be freed.  */
  if (lh->file_names)
    xfree (lh->file_names);

  /* Similarly for the include directory names.  */
  if (lh->include_dirs)
    xfree (lh->include_dirs);

  xfree (lh);
}


/* Add an entry to LH's include directory table.  */
static void
add_include_dir (struct line_header *lh, char *include_dir)
{
  /* Grow the array if necessary.  */
  if (lh->include_dirs_size == 0)
    {
      lh->include_dirs_size = 1; /* for testing */
      lh->include_dirs = xmalloc (lh->include_dirs_size
                                  * sizeof (*lh->include_dirs));
    }
  else if (lh->num_include_dirs >= lh->include_dirs_size)
    {
      lh->include_dirs_size *= 2;
      lh->include_dirs = xrealloc (lh->include_dirs,
                                   (lh->include_dirs_size
                                    * sizeof (*lh->include_dirs)));
    }

  lh->include_dirs[lh->num_include_dirs++] = include_dir;
}


/* Add an entry to LH's file name table.  */
static void
add_file_name (struct line_header *lh,
               char *name,
               unsigned int dir_index,
               unsigned int mod_time,
               unsigned int length)
{
  struct file_entry *fe;

  /* Grow the array if necessary.  */
  if (lh->file_names_size == 0)
    {
      lh->file_names_size = 1; /* for testing */
      lh->file_names = xmalloc (lh->file_names_size
                                * sizeof (*lh->file_names));
    }
  else if (lh->num_file_names >= lh->file_names_size)
    {
      lh->file_names_size *= 2;
      lh->file_names = xrealloc (lh->file_names,
                                 (lh->file_names_size
                                  * sizeof (*lh->file_names)));
    }

  fe = &lh->file_names[lh->num_file_names++];
  fe->name = name;
  fe->dir_index = dir_index;
  fe->mod_time = mod_time;
  fe->length = length;
  fe->included_p = 0;
  fe->symtab = NULL;
}


/* Read the statement program header starting at OFFSET in
   .debug_line, according to the endianness of ABFD.  Return a pointer
   to a struct line_header, allocated using xmalloc.

   NOTE: the strings in the include directory and file name tables of
   the returned object point into debug_line_buffer, and must not be
   freed.  */
static struct line_header *
dwarf_decode_line_header (unsigned int offset, bfd *abfd,
                          struct dwarf2_cu *cu)
{
  struct cleanup *back_to;
  struct line_header *lh;
  gdb_byte *line_ptr;
  unsigned int bytes_read, offset_size;
  int i;
  char *cur_dir, *cur_file;

  dwarf2_read_section (dwarf2_per_objfile->objfile, &dwarf2_per_objfile->line);
  if (dwarf2_per_objfile->line.buffer == NULL)
    {
      complaint (&symfile_complaints, _("missing .debug_line section"));
      return 0;
    }

  /* Make sure that at least there's room for the total_length field.
     That could be 12 bytes long, but we're just going to fudge that.  */
  if (offset + 4 >= dwarf2_per_objfile->line.size)
    {
      dwarf2_statement_list_fits_in_line_number_section_complaint ();
      return 0;
    }

  lh = xmalloc (sizeof (*lh));
  memset (lh, 0, sizeof (*lh));
  back_to = make_cleanup ((make_cleanup_ftype *) free_line_header,
                          (void *) lh);

  line_ptr = dwarf2_per_objfile->line.buffer + offset;

  /* Read in the header.  */
  lh->total_length =
    read_checked_initial_length_and_offset (abfd, line_ptr, &cu->header,
                                            &bytes_read, &offset_size);
  line_ptr += bytes_read;
  if (line_ptr + lh->total_length > (dwarf2_per_objfile->line.buffer
                                     + dwarf2_per_objfile->line.size))
    {
      dwarf2_statement_list_fits_in_line_number_section_complaint ();
      return 0;
    }
  lh->statement_program_end = line_ptr + lh->total_length;
  lh->version = read_2_bytes (abfd, line_ptr);
  line_ptr += 2;
  lh->header_length = read_offset_1 (abfd, line_ptr, offset_size);
  line_ptr += offset_size;
  lh->minimum_instruction_length = read_1_byte (abfd, line_ptr);
  line_ptr += 1;
  if (lh->version >= 4)
    {
      lh->maximum_ops_per_instruction = read_1_byte (abfd, line_ptr);
      line_ptr += 1;
    }
  else
    lh->maximum_ops_per_instruction = 1;

  if (lh->maximum_ops_per_instruction == 0)
    {
      lh->maximum_ops_per_instruction = 1;
      complaint (&symfile_complaints,
                 _("invalid maximum_ops_per_instruction in `.debug_line' section"));
    }

  lh->default_is_stmt = read_1_byte (abfd, line_ptr);
  line_ptr += 1;
  lh->line_base = read_1_signed_byte (abfd, line_ptr);
  line_ptr += 1;
  lh->line_range = read_1_byte (abfd, line_ptr);
  line_ptr += 1;
  lh->opcode_base = read_1_byte (abfd, line_ptr);
  line_ptr += 1;
  lh->standard_opcode_lengths
    = xmalloc (lh->opcode_base * sizeof (lh->standard_opcode_lengths[0]));

  lh->standard_opcode_lengths[0] = 1;  /* This should never be used anyway.  */
  for (i = 1; i < lh->opcode_base; ++i)
    {
      lh->standard_opcode_lengths[i] = read_1_byte (abfd, line_ptr);
      line_ptr += 1;
    }

  /* Read directory table.  */
  while ((cur_dir = read_string (abfd, line_ptr, &bytes_read)) != NULL)
    {
      line_ptr += bytes_read;
      add_include_dir (lh, cur_dir);
    }
  line_ptr += bytes_read;

  /* Read file name table.  */
  while ((cur_file = read_string (abfd, line_ptr, &bytes_read)) != NULL)
    {
      unsigned int dir_index, mod_time, length;

      line_ptr += bytes_read;
      dir_index = read_unsigned_leb128 (abfd, line_ptr, &bytes_read);
      line_ptr += bytes_read;
      mod_time = read_unsigned_leb128 (abfd, line_ptr, &bytes_read);
      line_ptr += bytes_read;
      length = read_unsigned_leb128 (abfd, line_ptr, &bytes_read);
      line_ptr += bytes_read;

      add_file_name (lh, cur_file, dir_index, mod_time, length);
    }
  line_ptr += bytes_read;
  lh->statement_program_start = line_ptr;

  if (line_ptr > (dwarf2_per_objfile->line.buffer
                  + dwarf2_per_objfile->line.size))
    complaint (&symfile_complaints,
               _("line number info header doesn't fit in `.debug_line' section"));

  discard_cleanups (back_to);
  return lh;
}

/* This function exists to work around a bug in certain compilers
   (particularly GCC 2.95), in which the first line number marker of a
   function does not show up until after the prologue, right before
   the second line number marker.  This function shifts ADDRESS down
   to the beginning of the function if necessary, and is called on
   addresses passed to record_line.  */

static CORE_ADDR
check_cu_functions (CORE_ADDR address, struct dwarf2_cu *cu)
{
  struct function_range *fn;

  /* Find the function_range containing address.  */
  if (!cu->first_fn)
    return address;

  if (!cu->cached_fn)
    cu->cached_fn = cu->first_fn;

  fn = cu->cached_fn;
  while (fn)
    if (fn->lowpc <= address && fn->highpc > address)
      goto found;
    else
      fn = fn->next;

  fn = cu->first_fn;
  while (fn && fn != cu->cached_fn)
    if (fn->lowpc <= address && fn->highpc > address)
      goto found;
    else
      fn = fn->next;

  return address;

 found:
  if (fn->seen_line)
    return address;
  if (address != fn->lowpc)
    complaint (&symfile_complaints,
               _("misplaced first line number at 0x%lx for '%s'"),
               (unsigned long) address, fn->name);
  fn->seen_line = 1;
  return fn->lowpc;
}

/* Decode the Line Number Program (LNP) for the given line_header
   structure and CU.  The actual information extracted and the type
   of structures created from the LNP depends on the value of PST.

   1. If PST is NULL, then this procedure uses the data from the program
      to create all necessary symbol tables, and their linetables.
      The compilation directory of the file is passed in COMP_DIR,
      and must not be NULL.

   2. If PST is not NULL, this procedure reads the program to determine
      the list of files included by the unit represented by PST, and
      builds all the associated partial symbol tables.  In this case,
      the value of COMP_DIR is ignored, and can thus be NULL (the COMP_DIR
      is not used to compute the full name of the symtab, and therefore
      omitting it when building the partial symtab does not introduce
      the potential for inconsistency - a partial symtab and its associated
      symbtab having a different fullname -).  */

static void
dwarf_decode_lines (struct line_header *lh, char *comp_dir, bfd *abfd,
                    struct dwarf2_cu *cu, struct partial_symtab *pst)
{
  gdb_byte *line_ptr, *extended_end;
  gdb_byte *line_end;
  unsigned int bytes_read, extended_len;
  unsigned char op_code, extended_op, adj_opcode;
  CORE_ADDR baseaddr;
  struct objfile *objfile = cu->objfile;
  struct gdbarch *gdbarch = get_objfile_arch (objfile);
  const int decode_for_pst_p = (pst != NULL);
  struct subfile *last_subfile = NULL, *first_subfile = current_subfile;

  baseaddr = ANOFFSET (objfile->section_offsets, SECT_OFF_TEXT (objfile));

  line_ptr = lh->statement_program_start;
  line_end = lh->statement_program_end;

  /* Read the statement sequences until there's nothing left.  */
  while (line_ptr < line_end)
    {
      /* state machine registers  */
      CORE_ADDR address = 0;
      unsigned int file = 1;
      unsigned int line = 1;
      unsigned int column = 0;
      int is_stmt = lh->default_is_stmt;
      int basic_block = 0;
      int end_sequence = 0;
      CORE_ADDR addr;
      unsigned char op_index = 0;

      if (!decode_for_pst_p && lh->num_file_names >= file)
        {
          /* Start a subfile for the current file of the state machine.  */
          /* lh->include_dirs and lh->file_names are 0-based, but the
             directory and file name numbers in the statement program
             are 1-based.  */
          struct file_entry *fe = &lh->file_names[file - 1];
          char *dir = NULL;

          if (fe->dir_index)
            dir = lh->include_dirs[fe->dir_index - 1];

          dwarf2_start_subfile (fe->name, dir, comp_dir);
        }

      /* Decode the table.  */
      while (!end_sequence)
        {
          op_code = read_1_byte (abfd, line_ptr);
          line_ptr += 1;
          if (line_ptr > line_end)
            {
              dwarf2_debug_line_missing_end_sequence_complaint ();
              break;
            }

          if (op_code >= lh->opcode_base)
            {
              /* Special operand.  */
              adj_opcode = op_code - lh->opcode_base;
              address += (((op_index + (adj_opcode / lh->line_range))
                           / lh->maximum_ops_per_instruction)
                          * lh->minimum_instruction_length);
              op_index = ((op_index + (adj_opcode / lh->line_range))
                          % lh->maximum_ops_per_instruction);
              line += lh->line_base + (adj_opcode % lh->line_range);
              if (lh->num_file_names < file || file == 0)
                dwarf2_debug_line_missing_file_complaint ();
              /* For now we ignore lines not starting on an
                 instruction boundary.  */
              else if (op_index == 0)
                {
                  lh->file_names[file - 1].included_p = 1;
                  if (!decode_for_pst_p && is_stmt)
                    {
                      if (last_subfile != current_subfile)
                        {
                          addr = gdbarch_addr_bits_remove (gdbarch, address);
                          if (last_subfile)
                            record_line (last_subfile, 0, addr);
                          last_subfile = current_subfile;
                        }
                      /* Append row to matrix using current values.  */
                      addr = check_cu_functions (address, cu);
                      addr = gdbarch_addr_bits_remove (gdbarch, addr);
                      record_line (current_subfile, line, addr);
                    }
                }
              basic_block = 0;
            }
          else switch (op_code)
            {
            case DW_LNS_extended_op:
              extended_len = read_unsigned_leb128 (abfd, line_ptr, &bytes_read);
              line_ptr += bytes_read;
              extended_end = line_ptr + extended_len;
              extended_op = read_1_byte (abfd, line_ptr);
              line_ptr += 1;
              switch (extended_op)
                {
                case DW_LNE_end_sequence:
                  end_sequence = 1;
                  break;
                case DW_LNE_set_address:
                  address = read_address (abfd, line_ptr, cu, &bytes_read);
                  op_index = 0;
                  line_ptr += bytes_read;
                  address += baseaddr;
                  break;
                case DW_LNE_define_file:
                  {
                    char *cur_file;
                    unsigned int dir_index, mod_time, length;

                    cur_file = read_string (abfd, line_ptr, &bytes_read);
                    line_ptr += bytes_read;
                    dir_index =
                      read_unsigned_leb128 (abfd, line_ptr, &bytes_read);
                    line_ptr += bytes_read;
                    mod_time =
                      read_unsigned_leb128 (abfd, line_ptr, &bytes_read);
                    line_ptr += bytes_read;
                    length =
                      read_unsigned_leb128 (abfd, line_ptr, &bytes_read);
                    line_ptr += bytes_read;
                    add_file_name (lh, cur_file, dir_index, mod_time, length);
                  }
                  break;
                case DW_LNE_set_discriminator:
                  /* The discriminator is not interesting to the debugger;
                     just ignore it.  */
                  line_ptr = extended_end;
                  break;
                default:
                  complaint (&symfile_complaints,
                             _("mangled .debug_line section"));
                  return;
                }
              /* Make sure that we parsed the extended op correctly.  If e.g.
                 we expected a different address size than the producer used,
                 we may have read the wrong number of bytes.  */
              if (line_ptr != extended_end)
                {
                  complaint (&symfile_complaints,
                             _("mangled .debug_line section"));
                  return;
                }
              break;
            case DW_LNS_copy:
              if (lh->num_file_names < file || file == 0)
                dwarf2_debug_line_missing_file_complaint ();
              else
                {
                  lh->file_names[file - 1].included_p = 1;
                  if (!decode_for_pst_p && is_stmt)
                    {
                      if (last_subfile != current_subfile)
                        {
                          addr = gdbarch_addr_bits_remove (gdbarch, address);
                          if (last_subfile)
                            record_line (last_subfile, 0, addr);
                          last_subfile = current_subfile;
                        }
                      addr = check_cu_functions (address, cu);
                      addr = gdbarch_addr_bits_remove (gdbarch, addr);
                      record_line (current_subfile, line, addr);
                    }
                }
              basic_block = 0;
              break;
            case DW_LNS_advance_pc:
              {
                CORE_ADDR adjust
                  = read_unsigned_leb128 (abfd, line_ptr, &bytes_read);

                address += (((op_index + adjust)
                             / lh->maximum_ops_per_instruction)
                            * lh->minimum_instruction_length);
                op_index = ((op_index + adjust)
                            % lh->maximum_ops_per_instruction);
                line_ptr += bytes_read;
              }
              break;
            case DW_LNS_advance_line:
              line += read_signed_leb128 (abfd, line_ptr, &bytes_read);
              line_ptr += bytes_read;
              break;
            case DW_LNS_set_file:
              {
                /* The arrays lh->include_dirs and lh->file_names are
                   0-based, but the directory and file name numbers in
                   the statement program are 1-based.  */
                struct file_entry *fe;
                char *dir = NULL;

                file = read_unsigned_leb128 (abfd, line_ptr, &bytes_read);
                line_ptr += bytes_read;
                if (lh->num_file_names < file || file == 0)
                  dwarf2_debug_line_missing_file_complaint ();
                else
                  {
                    fe = &lh->file_names[file - 1];
                    if (fe->dir_index)
                      dir = lh->include_dirs[fe->dir_index - 1];
                    if (!decode_for_pst_p)
                      {
                        last_subfile = current_subfile;
                        dwarf2_start_subfile (fe->name, dir, comp_dir);
                      }
                  }
              }
              break;
            case DW_LNS_set_column:
              column = read_unsigned_leb128 (abfd, line_ptr, &bytes_read);
              line_ptr += bytes_read;
              break;
            case DW_LNS_negate_stmt:
              is_stmt = (!is_stmt);
              break;
            case DW_LNS_set_basic_block:
              basic_block = 1;
              break;
            /* Add to the address register of the state machine the
               address increment value corresponding to special opcode
               255.  I.e., this value is scaled by the minimum
               instruction length since special opcode 255 would have
               scaled the the increment.  */
            case DW_LNS_const_add_pc:
              {
                CORE_ADDR adjust = (255 - lh->opcode_base) / lh->line_range;

                address += (((op_index + adjust)
                             / lh->maximum_ops_per_instruction)
                            * lh->minimum_instruction_length);
                op_index = ((op_index + adjust)
                            % lh->maximum_ops_per_instruction);
              }
              break;
            case DW_LNS_fixed_advance_pc:
              address += read_2_bytes (abfd, line_ptr);
              op_index = 0;
              line_ptr += 2;
              break;
            default:
              {
                /* Unknown standard opcode, ignore it.  */
                int i;

                for (i = 0; i < lh->standard_opcode_lengths[op_code]; i++)
                  {
                    (void) read_unsigned_leb128 (abfd, line_ptr, &bytes_read);
                    line_ptr += bytes_read;
                  }
              }
            }
        }
      if (lh->num_file_names < file || file == 0)
        dwarf2_debug_line_missing_file_complaint ();
      else
        {
          lh->file_names[file - 1].included_p = 1;
          if (!decode_for_pst_p)
            {
              addr = gdbarch_addr_bits_remove (gdbarch, address);
              record_line (current_subfile, 0, addr);
            }
        }
    }

  if (decode_for_pst_p)
    {
      int file_index;

      /* Now that we're done scanning the Line Header Program, we can
         create the psymtab of each included file.  */
      for (file_index = 0; file_index < lh->num_file_names; file_index++)
        if (lh->file_names[file_index].included_p == 1)
          {
            const struct file_entry fe = lh->file_names [file_index];
            char *include_name = fe.name;
            char *dir_name = NULL;
            char *pst_filename = pst->filename;

            if (fe.dir_index)
              dir_name = lh->include_dirs[fe.dir_index - 1];

            if (!IS_ABSOLUTE_PATH (include_name) && dir_name != NULL)
              {
                include_name = concat (dir_name, SLASH_STRING,
                                       include_name, (char *)NULL);
                make_cleanup (xfree, include_name);
              }

            if (!IS_ABSOLUTE_PATH (pst_filename) && pst->dirname != NULL)
              {
                pst_filename = concat (pst->dirname, SLASH_STRING,
                                       pst_filename, (char *)NULL);
                make_cleanup (xfree, pst_filename);
              }

            if (strcmp (include_name, pst_filename) != 0)
              dwarf2_create_include_psymtab (include_name, pst, objfile);
          }
    }
  else
    {
      /* Make sure a symtab is created for every file, even files
         which contain only variables (i.e. no code with associated
         line numbers).  */

      int i;
      struct file_entry *fe;

      for (i = 0; i < lh->num_file_names; i++)
        {
          char *dir = NULL;

          fe = &lh->file_names[i];
          if (fe->dir_index)
            dir = lh->include_dirs[fe->dir_index - 1];
          dwarf2_start_subfile (fe->name, dir, comp_dir);

          /* Skip the main file; we don't need it, and it must be
             allocated last, so that it will show up before the
             non-primary symtabs in the objfile's symtab list.  */
          if (current_subfile == first_subfile)
            continue;

          if (current_subfile->symtab == NULL)
            current_subfile->symtab = allocate_symtab (current_subfile->name,
                                                       cu->objfile);
          fe->symtab = current_subfile->symtab;
        }
    }
}

/* Start a subfile for DWARF.  FILENAME is the name of the file and
   DIRNAME the name of the source directory which contains FILENAME
   or NULL if not known.  COMP_DIR is the compilation directory for the
   linetable's compilation unit or NULL if not known.
   This routine tries to keep line numbers from identical absolute and
   relative file names in a common subfile.

   Using the `list' example from the GDB testsuite, which resides in
   /srcdir and compiling it with Irix6.2 cc in /compdir using a filename
   of /srcdir/list0.c yields the following debugging information for list0.c:

   DW_AT_name:          /srcdir/list0.c
   DW_AT_comp_dir:              /compdir
   files.files[0].name: list0.h
   files.files[0].dir:  /srcdir
   files.files[1].name: list0.c
   files.files[1].dir:  /srcdir

   The line number information for list0.c has to end up in a single
   subfile, so that `break /srcdir/list0.c:1' works as expected.
   start_subfile will ensure that this happens provided that we pass the
   concatenation of files.files[1].dir and files.files[1].name as the
   subfile's name.  */

static void
dwarf2_start_subfile (char *filename, char *dirname, char *comp_dir)
{
  char *fullname;

  /* While reading the DIEs, we call start_symtab(DW_AT_name, DW_AT_comp_dir).
     `start_symtab' will always pass the contents of DW_AT_comp_dir as
     second argument to start_subfile.  To be consistent, we do the
     same here.  In order not to lose the line information directory,
     we concatenate it to the filename when it makes sense.
     Note that the Dwarf3 standard says (speaking of filenames in line
     information): ``The directory index is ignored for file names
     that represent full path names''.  Thus ignoring dirname in the
     `else' branch below isn't an issue.  */

  if (!IS_ABSOLUTE_PATH (filename) && dirname != NULL)
    fullname = concat (dirname, SLASH_STRING, filename, (char *)NULL);
  else
    fullname = filename;

  start_subfile (fullname, comp_dir);

  if (fullname != filename)
    xfree (fullname);
}

static void
var_decode_location (struct attribute *attr, struct symbol *sym,
                     struct dwarf2_cu *cu)
{
  struct objfile *objfile = cu->objfile;
  struct comp_unit_head *cu_header = &cu->header;

  /* NOTE drow/2003-01-30: There used to be a comment and some special
     code here to turn a symbol with DW_AT_external and a
     SYMBOL_VALUE_ADDRESS of 0 into a LOC_UNRESOLVED symbol.  This was
     necessary for platforms (maybe Alpha, certainly PowerPC GNU/Linux
     with some versions of binutils) where shared libraries could have
     relocations against symbols in their debug information - the
     minimal symbol would have the right address, but the debug info
     would not.  It's no longer necessary, because we will explicitly
     apply relocations when we read in the debug information now.  */

  /* A DW_AT_location attribute with no contents indicates that a
     variable has been optimized away.  */
  if (attr_form_is_block (attr) && DW_BLOCK (attr)->size == 0)
    {
      SYMBOL_CLASS (sym) = LOC_OPTIMIZED_OUT;
      return;
    }

  /* Handle one degenerate form of location expression specially, to
     preserve GDB's previous behavior when section offsets are
     specified.  If this is just a DW_OP_addr then mark this symbol
     as LOC_STATIC.  */

  if (attr_form_is_block (attr)
      && DW_BLOCK (attr)->size == 1 + cu_header->addr_size
      && DW_BLOCK (attr)->data[0] == DW_OP_addr)
    {
      unsigned int dummy;

      SYMBOL_VALUE_ADDRESS (sym) =
        read_address (objfile->obfd, DW_BLOCK (attr)->data + 1, cu, &dummy);
      SYMBOL_CLASS (sym) = LOC_STATIC;
      fixup_symbol_section (sym, objfile);
      SYMBOL_VALUE_ADDRESS (sym) += ANOFFSET (objfile->section_offsets,
                                              SYMBOL_SECTION (sym));
      return;
    }

  /* NOTE drow/2002-01-30: It might be worthwhile to have a static
     expression evaluator, and use LOC_COMPUTED only when necessary
     (i.e. when the value of a register or memory location is
     referenced, or a thread-local block, etc.).  Then again, it might
     not be worthwhile.  I'm assuming that it isn't unless performance
     or memory numbers show me otherwise.  */

  dwarf2_symbol_mark_computed (attr, sym, cu);
  SYMBOL_CLASS (sym) = LOC_COMPUTED;
}

/* Given a pointer to a DWARF information entry, figure out if we need
   to make a symbol table entry for it, and if so, create a new entry
   and return a pointer to it.
   If TYPE is NULL, determine symbol type from the die, otherwise
   used the passed type.  */

static struct symbol *
new_symbol (struct die_info *die, struct type *type, struct dwarf2_cu *cu)
{
  struct objfile *objfile = cu->objfile;
  struct symbol *sym = NULL;
  char *name;
  struct attribute *attr = NULL;
  struct attribute *attr2 = NULL;
  CORE_ADDR baseaddr;
  int inlined_func = (die->tag == DW_TAG_inlined_subroutine);

  baseaddr = ANOFFSET (objfile->section_offsets, SECT_OFF_TEXT (objfile));

  name = dwarf2_name (die, cu);
  if (name)
    {
      const char *linkagename;

      sym = (struct symbol *) obstack_alloc (&objfile->objfile_obstack,
                                             sizeof (struct symbol));
      OBJSTAT (objfile, n_syms++);
      memset (sym, 0, sizeof (struct symbol));

      /* Cache this symbol's name and the name's demangled form (if any).  */
      SYMBOL_LANGUAGE (sym) = cu->language;
      linkagename = dwarf2_physname (name, die, cu);
      SYMBOL_SET_NAMES (sym, linkagename, strlen (linkagename), 0, objfile);

      /* Fortran does not have mangling standard and the mangling does differ
         between gfortran, iFort etc.  */
      if (cu->language == language_fortran
          && sym->ginfo.language_specific.cplus_specific.demangled_name == NULL)
        sym->ginfo.language_specific.cplus_specific.demangled_name
          = (char *) dwarf2_full_name (name, die, cu);

      /* Default assumptions.
         Use the passed type or decode it from the die.  */
      SYMBOL_DOMAIN (sym) = VAR_DOMAIN;
      SYMBOL_CLASS (sym) = LOC_OPTIMIZED_OUT;
      if (type != NULL)
        SYMBOL_TYPE (sym) = type;
      else
        SYMBOL_TYPE (sym) = die_type (die, cu);
      attr = dwarf2_attr (die,
                          inlined_func ? DW_AT_call_line : DW_AT_decl_line,
                          cu);
      if (attr)
        {
          SYMBOL_LINE (sym) = DW_UNSND (attr);
        }

      attr = dwarf2_attr (die,
                          inlined_func ? DW_AT_call_file : DW_AT_decl_file,
                          cu);
      if (attr)
        {
          int file_index = DW_UNSND (attr);

          if (cu->line_header == NULL
              || file_index > cu->line_header->num_file_names)
            complaint (&symfile_complaints,
                       _("file index out of range"));
          else if (file_index > 0)
            {
              struct file_entry *fe;

              fe = &cu->line_header->file_names[file_index - 1];
              SYMBOL_SYMTAB (sym) = fe->symtab;
            }
        }

      switch (die->tag)
        {
        case DW_TAG_label:
          attr = dwarf2_attr (die, DW_AT_low_pc, cu);
          if (attr)
            {
              SYMBOL_VALUE_ADDRESS (sym) = DW_ADDR (attr) + baseaddr;
            }
          SYMBOL_TYPE (sym) = objfile_type (objfile)->builtin_core_addr;
          SYMBOL_DOMAIN (sym) = LABEL_DOMAIN;
          SYMBOL_CLASS (sym) = LOC_LABEL;
          add_symbol_to_list (sym, cu->list_in_scope);
          break;
        case DW_TAG_subprogram:
          /* SYMBOL_BLOCK_VALUE (sym) will be filled in later by
             finish_block.  */
          SYMBOL_CLASS (sym) = LOC_BLOCK;
          attr2 = dwarf2_attr (die, DW_AT_external, cu);
          if ((attr2 && (DW_UNSND (attr2) != 0))
              || cu->language == language_ada)
            {
              /* Subprograms marked external are stored as a global symbol.
                 Ada subprograms, whether marked external or not, are always
                 stored as a global symbol, because we want to be able to
                 access them globally.  For instance, we want to be able
                 to break on a nested subprogram without having to
                 specify the context.  */
              add_symbol_to_list (sym, &global_symbols);
            }
          else
            {
              add_symbol_to_list (sym, cu->list_in_scope);
            }
          break;
        case DW_TAG_inlined_subroutine:
          /* SYMBOL_BLOCK_VALUE (sym) will be filled in later by
             finish_block.  */
          SYMBOL_CLASS (sym) = LOC_BLOCK;
          SYMBOL_INLINED (sym) = 1;
          /* Do not add the symbol to any lists.  It will be found via
             BLOCK_FUNCTION from the blockvector.  */
          break;
        case DW_TAG_variable:
        case DW_TAG_member:
          /* Compilation with minimal debug info may result in variables
             with missing type entries. Change the misleading `void' type
             to something sensible.  */
          if (TYPE_CODE (SYMBOL_TYPE (sym)) == TYPE_CODE_VOID)
            SYMBOL_TYPE (sym)
              = objfile_type (objfile)->nodebug_data_symbol;

          attr = dwarf2_attr (die, DW_AT_const_value, cu);
          /* In the case of DW_TAG_member, we should only be called for
             static const members.  */
          if (die->tag == DW_TAG_member)
            {
              /* dwarf2_add_field uses die_is_declaration,
                 so we do the same.  */
              gdb_assert (die_is_declaration (die, cu));
              gdb_assert (attr);
            }
          if (attr)
            {
              dwarf2_const_value (attr, sym, cu);
              attr2 = dwarf2_attr (die, DW_AT_external, cu);
              if (attr2 && (DW_UNSND (attr2) != 0))
                add_symbol_to_list (sym, &global_symbols);
              else
                add_symbol_to_list (sym, cu->list_in_scope);
              break;
            }
          attr = dwarf2_attr (die, DW_AT_location, cu);
          if (attr)
            {
              var_decode_location (attr, sym, cu);
              attr2 = dwarf2_attr (die, DW_AT_external, cu);
              if (attr2 && (DW_UNSND (attr2) != 0))
                {
                  struct pending **list_to_add;

                  /* Workaround gfortran PR debug/40040 - it uses
                     DW_AT_location for variables in -fPIC libraries which may
                     get overriden by other libraries/executable and get
                     a different address.  Resolve it by the minimal symbol
                     which may come from inferior's executable using copy
                     relocation.  Make this workaround only for gfortran as for
                     other compilers GDB cannot guess the minimal symbol
                     Fortran mangling kind.  */
                  if (cu->language == language_fortran && die->parent
                      && die->parent->tag == DW_TAG_module
                      && cu->producer
                      && strncmp (cu->producer, "GNU Fortran ", 12) == 0)
                    SYMBOL_CLASS (sym) = LOC_UNRESOLVED;

                  /* A variable with DW_AT_external is never static,
                     but it may be block-scoped.  */
                  list_to_add = (cu->list_in_scope == &file_symbols
                                 ? &global_symbols : cu->list_in_scope);
                  add_symbol_to_list (sym, list_to_add);
                }
              else
                add_symbol_to_list (sym, cu->list_in_scope);
            }
          else
            {
              /* We do not know the address of this symbol.
                 If it is an external symbol and we have type information
                 for it, enter the symbol as a LOC_UNRESOLVED symbol.
                 The address of the variable will then be determined from
                 the minimal symbol table whenever the variable is
                 referenced.  */
              attr2 = dwarf2_attr (die, DW_AT_external, cu);
              if (attr2 && (DW_UNSND (attr2) != 0)
                  && dwarf2_attr (die, DW_AT_type, cu) != NULL)
                {
                  struct pending **list_to_add;

                  /* A variable with DW_AT_external is never static, but it
                     may be block-scoped.  */
                  list_to_add = (cu->list_in_scope == &file_symbols
                                 ? &global_symbols : cu->list_in_scope);

                  SYMBOL_CLASS (sym) = LOC_UNRESOLVED;
                  add_symbol_to_list (sym, list_to_add);
                }
              else if (!die_is_declaration (die, cu))
                {
                  /* Use the default LOC_OPTIMIZED_OUT class.  */
                  gdb_assert (SYMBOL_CLASS (sym) == LOC_OPTIMIZED_OUT);
                  add_symbol_to_list (sym, cu->list_in_scope);
                }
            }
          break;
        case DW_TAG_formal_parameter:
          /* If we are inside a function, mark this as an argument.  If
             not, we might be looking at an argument to an inlined function
             when we do not have enough information to show inlined frames;
             pretend it's a local variable in that case so that the user can
             still see it.  */
          if (context_stack_depth > 0
              && context_stack[context_stack_depth - 1].name != NULL)
            SYMBOL_IS_ARGUMENT (sym) = 1;
          attr = dwarf2_attr (die, DW_AT_location, cu);
          if (attr)
            {
              var_decode_location (attr, sym, cu);
            }
          attr = dwarf2_attr (die, DW_AT_const_value, cu);
          if (attr)
            {
              dwarf2_const_value (attr, sym, cu);
            }
          attr = dwarf2_attr (die, DW_AT_variable_parameter, cu);
          if (attr && DW_UNSND (attr))
            {
              struct type *ref_type;

              ref_type = lookup_reference_type (SYMBOL_TYPE (sym));
              SYMBOL_TYPE (sym) = ref_type;
            }

          add_symbol_to_list (sym, cu->list_in_scope);
          break;
        case DW_TAG_unspecified_parameters:
          /* From varargs functions; gdb doesn't seem to have any
             interest in this information, so just ignore it for now.
             (FIXME?) */
          break;
        case DW_TAG_class_type:
        case DW_TAG_interface_type:
        case DW_TAG_structure_type:
        case DW_TAG_union_type:
        case DW_TAG_set_type:
        case DW_TAG_enumeration_type:
          SYMBOL_CLASS (sym) = LOC_TYPEDEF;
          SYMBOL_DOMAIN (sym) = STRUCT_DOMAIN;

          {
            /* NOTE: carlton/2003-11-10: C++ and Java class symbols shouldn't
               really ever be static objects: otherwise, if you try
               to, say, break of a class's method and you're in a file
               which doesn't mention that class, it won't work unless
               the check for all static symbols in lookup_symbol_aux
               saves you.  See the OtherFileClass tests in
               gdb.c++/namespace.exp.  */

            struct pending **list_to_add;

            list_to_add = (cu->list_in_scope == &file_symbols
                           && (cu->language == language_cplus
                               || cu->language == language_java)
                           ? &global_symbols : cu->list_in_scope);

            add_symbol_to_list (sym, list_to_add);

            /* The semantics of C++ state that "struct foo { ... }" also
               defines a typedef for "foo".  A Java class declaration also
               defines a typedef for the class.  */
            if (cu->language == language_cplus
                || cu->language == language_java
                || cu->language == language_ada)
              {
                /* The symbol's name is already allocated along with
                   this objfile, so we don't need to duplicate it for
                   the type.  */
                if (TYPE_NAME (SYMBOL_TYPE (sym)) == 0)
                  TYPE_NAME (SYMBOL_TYPE (sym)) = SYMBOL_SEARCH_NAME (sym);
              }
          }
          break;
        case DW_TAG_typedef:
          SYMBOL_CLASS (sym) = LOC_TYPEDEF;
          SYMBOL_DOMAIN (sym) = VAR_DOMAIN;
          add_symbol_to_list (sym, cu->list_in_scope);
          break;
        case DW_TAG_base_type:
        case DW_TAG_subrange_type:
        case DW_TAG_const_type:
        case DW_TAG_volatile_type:
          SYMBOL_CLASS (sym) = LOC_TYPEDEF;
          SYMBOL_DOMAIN (sym) = VAR_DOMAIN;
          add_symbol_to_list (sym, cu->list_in_scope);
          break;
        case DW_TAG_enumerator:
          attr = dwarf2_attr (die, DW_AT_const_value, cu);
          if (attr)
            {
              dwarf2_const_value (attr, sym, cu);
            }
          {
            /* NOTE: carlton/2003-11-10: See comment above in the
               DW_TAG_class_type, etc. block.  */

            struct pending **list_to_add;

            list_to_add = (cu->list_in_scope == &file_symbols
                           && (cu->language == language_cplus
                               || cu->language == language_java)
                           ? &global_symbols : cu->list_in_scope);

            add_symbol_to_list (sym, list_to_add);
          }
          break;
        case DW_TAG_namespace:
          SYMBOL_CLASS (sym) = LOC_TYPEDEF;
          add_symbol_to_list (sym, &global_symbols);
          break;
        default:
          /* Not a tag we recognize.  Hopefully we aren't processing
             trash data, but since we must specifically ignore things
             we don't recognize, there is nothing else we should do at
             this point. */
          complaint (&symfile_complaints, _("unsupported tag: '%s'"),
                     dwarf_tag_name (die->tag));
          break;
        }

      /* For the benefit of old versions of GCC, check for anonymous
         namespaces based on the demangled name.  */
      if (!processing_has_namespace_info
          && cu->language == language_cplus)
        cp_scan_for_anonymous_namespaces (sym);
    }
  return (sym);
}

/* Copy constant value from an attribute to a symbol.  */

static void
dwarf2_const_value (struct attribute *attr, struct symbol *sym,
                    struct dwarf2_cu *cu)
{
  struct objfile *objfile = cu->objfile;
  struct comp_unit_head *cu_header = &cu->header;
  enum bfd_endian byte_order = bfd_big_endian (objfile->obfd) ?
                                BFD_ENDIAN_BIG : BFD_ENDIAN_LITTLE;
  struct dwarf_block *blk;

  switch (attr->form)
    {
    case DW_FORM_addr:
      {
        struct dwarf2_locexpr_baton *baton;
        gdb_byte *data;

        if (TYPE_LENGTH (SYMBOL_TYPE (sym)) != cu_header->addr_size)
          dwarf2_const_value_length_mismatch_complaint (SYMBOL_PRINT_NAME (sym),
                                                        cu_header->addr_size,
                                                        TYPE_LENGTH (SYMBOL_TYPE
                                                                     (sym)));
        /* Symbols of this form are reasonably rare, so we just
           piggyback on the existing location code rather than writing
           a new implementation of symbol_computed_ops.  */
        baton = obstack_alloc (&objfile->objfile_obstack,
                               sizeof (struct dwarf2_locexpr_baton));
        baton->per_cu = cu->per_cu;
        gdb_assert (baton->per_cu);

        baton->size = 2 + cu_header->addr_size;
        data = obstack_alloc (&objfile->objfile_obstack, baton->size);
        baton->data = data;

        data[0] = DW_OP_addr;
        store_unsigned_integer (&data[1], cu_header->addr_size,
                                byte_order, DW_ADDR (attr));
        data[cu_header->addr_size + 1] = DW_OP_stack_value;

        SYMBOL_COMPUTED_OPS (sym) = &dwarf2_locexpr_funcs;
        SYMBOL_LOCATION_BATON (sym) = baton;
        SYMBOL_CLASS (sym) = LOC_COMPUTED;
      }
      break;
    case DW_FORM_string:
    case DW_FORM_strp:
      /* DW_STRING is already allocated on the obstack, point directly
         to it.  */
      SYMBOL_VALUE_BYTES (sym) = (gdb_byte *) DW_STRING (attr);
      SYMBOL_CLASS (sym) = LOC_CONST_BYTES;
      break;
    case DW_FORM_block1:
    case DW_FORM_block2:
    case DW_FORM_block4:
    case DW_FORM_block:
    case DW_FORM_exprloc:
      blk = DW_BLOCK (attr);
      if (TYPE_LENGTH (SYMBOL_TYPE (sym)) != blk->size)
        dwarf2_const_value_length_mismatch_complaint (SYMBOL_PRINT_NAME (sym),
                                                      blk->size,
                                                      TYPE_LENGTH (SYMBOL_TYPE
                                                                   (sym)));
      SYMBOL_VALUE_BYTES (sym) =
        obstack_alloc (&objfile->objfile_obstack, blk->size);
      memcpy (SYMBOL_VALUE_BYTES (sym), blk->data, blk->size);
      SYMBOL_CLASS (sym) = LOC_CONST_BYTES;
      break;

      /* The DW_AT_const_value attributes are supposed to carry the
         symbol's value "represented as it would be on the target
         architecture."  By the time we get here, it's already been
         converted to host endianness, so we just need to sign- or
         zero-extend it as appropriate.  */
    case DW_FORM_data1:
      dwarf2_const_value_data (attr, sym, 8);
      break;
    case DW_FORM_data2:
      dwarf2_const_value_data (attr, sym, 16);
      break;
    case DW_FORM_data4:
      dwarf2_const_value_data (attr, sym, 32);
      break;
    case DW_FORM_data8:
      dwarf2_const_value_data (attr, sym, 64);
      break;

    case DW_FORM_sdata:
      SYMBOL_VALUE (sym) = DW_SND (attr);
      SYMBOL_CLASS (sym) = LOC_CONST;
      break;

    case DW_FORM_udata:
      SYMBOL_VALUE (sym) = DW_UNSND (attr);
      SYMBOL_CLASS (sym) = LOC_CONST;
      break;

    default:
      complaint (&symfile_complaints,
                 _("unsupported const value attribute form: '%s'"),
                 dwarf_form_name (attr->form));
      SYMBOL_VALUE (sym) = 0;
      SYMBOL_CLASS (sym) = LOC_CONST;
      break;
    }
}


/* Given an attr with a DW_FORM_dataN value in host byte order, sign-
   or zero-extend it as appropriate for the symbol's type.  */
static void
dwarf2_const_value_data (struct attribute *attr,
                         struct symbol *sym,
                         int bits)
{
  LONGEST l = DW_UNSND (attr);

  if (bits < sizeof (l) * 8)
    {
      if (TYPE_UNSIGNED (SYMBOL_TYPE (sym)))
        l &= ((LONGEST) 1 << bits) - 1;
      else
        l = (l << (sizeof (l) * 8 - bits)) >> (sizeof (l) * 8 - bits);
    }

  SYMBOL_VALUE (sym) = l;
  SYMBOL_CLASS (sym) = LOC_CONST;
}


/* Return the type of the die in question using its DW_AT_type attribute.  */

static struct type *
die_type (struct die_info *die, struct dwarf2_cu *cu)
{
  struct attribute *type_attr;
  struct die_info *type_die;

  type_attr = dwarf2_attr (die, DW_AT_type, cu);
  if (!type_attr)
    {
      /* A missing DW_AT_type represents a void type.  */
      return objfile_type (cu->objfile)->builtin_void;
    }

  type_die = follow_die_ref_or_sig (die, type_attr, &cu);

  return tag_type_to_type (type_die, cu);
}

/* True iff CU's producer generates GNAT Ada auxiliary information
   that allows to find parallel types through that information instead
   of having to do expensive parallel lookups by type name.  */

static int
need_gnat_info (struct dwarf2_cu *cu)
{
  /* FIXME: brobecker/2010-10-12: As of now, only the AdaCore version
     of GNAT produces this auxiliary information, without any indication
     that it is produced.  Part of enhancing the FSF version of GNAT
     to produce that information will be to put in place an indicator
     that we can use in order to determine whether the descriptive type
     info is available or not.  One suggestion that has been made is
     to use a new attribute, attached to the CU die.  For now, assume
     that the descriptive type info is not available.  */
  return 0;
}


/* Return the auxiliary type of the die in question using its
   DW_AT_GNAT_descriptive_type attribute.  Returns NULL if the
   attribute is not present.  */

static struct type *
die_descriptive_type (struct die_info *die, struct dwarf2_cu *cu)
{
  struct attribute *type_attr;
  struct die_info *type_die;

  type_attr = dwarf2_attr (die, DW_AT_GNAT_descriptive_type, cu);
  if (!type_attr)
    return NULL;

  type_die = follow_die_ref (die, type_attr, &cu);
  return tag_type_to_type (type_die, cu);
}

/* If DIE has a descriptive_type attribute, then set the TYPE's
   descriptive type accordingly.  */

static void
set_descriptive_type (struct type *type, struct die_info *die,
                      struct dwarf2_cu *cu)
{
  struct type *descriptive_type = die_descriptive_type (die, cu);

  if (descriptive_type)
    {
      ALLOCATE_GNAT_AUX_TYPE (type);
      TYPE_DESCRIPTIVE_TYPE (type) = descriptive_type;
    }
}

/* Return the containing type of the die in question using its
   DW_AT_containing_type attribute.  */

static struct type *
die_containing_type (struct die_info *die, struct dwarf2_cu *cu)
{
  struct attribute *type_attr;
  struct die_info *type_die;

  type_attr = dwarf2_attr (die, DW_AT_containing_type, cu);
  if (!type_attr)
    error (_("Dwarf Error: Problem turning containing type into gdb type "
             "[in module %s]"), cu->objfile->name);

  type_die = follow_die_ref_or_sig (die, type_attr, &cu);
  return tag_type_to_type (type_die, cu);
}

static struct type *
tag_type_to_type (struct die_info *die, struct dwarf2_cu *cu)
{
  struct type *this_type;

  this_type = read_type_die (die, cu);
  if (!this_type)
    {
      char *message, *saved;

      /* read_type_die already issued a complaint.  */
      message = xstrprintf (_("<unknown type in %s, CU 0x%x, DIE 0x%x>"),
                            cu->objfile->name,
                            cu->header.offset,
                            die->offset);
      saved = obstack_copy0 (&cu->objfile->objfile_obstack,
                             message, strlen (message));
      xfree (message);

      this_type = init_type (TYPE_CODE_ERROR, 0, 0, saved, cu->objfile);
    }
  return this_type;
}

static struct type *
read_type_die (struct die_info *die, struct dwarf2_cu *cu)
{
  struct type *this_type;

  this_type = get_die_type (die, cu);
  if (this_type)
    return this_type;

  switch (die->tag)
    {
    case DW_TAG_class_type:
    case DW_TAG_interface_type:
    case DW_TAG_structure_type:
    case DW_TAG_union_type:
      this_type = read_structure_type (die, cu);
      break;
    case DW_TAG_enumeration_type:
      this_type = read_enumeration_type (die, cu);
      break;
    case DW_TAG_subprogram:
    case DW_TAG_subroutine_type:
    case DW_TAG_inlined_subroutine:
      this_type = read_subroutine_type (die, cu);
      break;
    case DW_TAG_array_type:
      this_type = read_array_type (die, cu);
      break;
    case DW_TAG_set_type:
      this_type = read_set_type (die, cu);
      break;
    case DW_TAG_pointer_type:
      this_type = read_tag_pointer_type (die, cu);
      break;
    case DW_TAG_ptr_to_member_type:
      this_type = read_tag_ptr_to_member_type (die, cu);
      break;
    case DW_TAG_reference_type:
      this_type = read_tag_reference_type (die, cu);
      break;
    case DW_TAG_const_type:
      this_type = read_tag_const_type (die, cu);
      break;
    case DW_TAG_volatile_type:
      this_type = read_tag_volatile_type (die, cu);
      break;
    case DW_TAG_string_type:
      this_type = read_tag_string_type (die, cu);
      break;
    case DW_TAG_typedef:
      this_type = read_typedef (die, cu);
      break;
    case DW_TAG_subrange_type:
      this_type = read_subrange_type (die, cu);
      break;
    case DW_TAG_base_type:
      this_type = read_base_type (die, cu);
      break;
    case DW_TAG_unspecified_type:
      this_type = read_unspecified_type (die, cu);
      break;
    case DW_TAG_namespace:
      this_type = read_namespace_type (die, cu);
      break;
    case DW_TAG_module:
      this_type = read_module_type (die, cu);
      break;
    default:
      complaint (&symfile_complaints, _("unexpected tag in read_type_die: '%s'"),
                 dwarf_tag_name (die->tag));
      break;
    }

  return this_type;
}

/* Return the name of the namespace/class that DIE is defined within,
   or "" if we can't tell.  The caller should not xfree the result.

   For example, if we're within the method foo() in the following
   code:

   namespace N {
     class C {
       void foo () {
       }
     };
   }

   then determine_prefix on foo's die will return "N::C".  */

static char *
determine_prefix (struct die_info *die, struct dwarf2_cu *cu)
{
  struct die_info *parent, *spec_die;
  struct dwarf2_cu *spec_cu;
  struct type *parent_type;

  if (cu->language != language_cplus && cu->language != language_java
      && cu->language != language_fortran)
    return "";

  /* We have to be careful in the presence of DW_AT_specification.
     For example, with GCC 3.4, given the code

     namespace N {
       void foo() {
         // Definition of N::foo.
       }
     }

     then we'll have a tree of DIEs like this:

     1: DW_TAG_compile_unit
       2: DW_TAG_namespace        // N
         3: DW_TAG_subprogram     // declaration of N::foo
       4: DW_TAG_subprogram       // definition of N::foo
            DW_AT_specification   // refers to die #3

     Thus, when processing die #4, we have to pretend that we're in
     the context of its DW_AT_specification, namely the contex of die
     #3.  */
  spec_cu = cu;
  spec_die = die_specification (die, &spec_cu);
  if (spec_die == NULL)
    parent = die->parent;
  else
    {
      parent = spec_die->parent;
      cu = spec_cu;
    }

  if (parent == NULL)
    return "";
  else
    switch (parent->tag)
      {
      case DW_TAG_namespace:
        parent_type = read_type_die (parent, cu);
        /* GCC 4.0 and 4.1 had a bug (PR c++/28460) where they generated bogus
           DW_TAG_namespace DIEs with a name of "::" for the global namespace.
           Work around this problem here.  */
        if (cu->language == language_cplus
            && strcmp (TYPE_TAG_NAME (parent_type), "::") == 0)
          return "";
        /* We give a name to even anonymous namespaces.  */
        return TYPE_TAG_NAME (parent_type);
      case DW_TAG_class_type:
      case DW_TAG_interface_type:
      case DW_TAG_structure_type:
      case DW_TAG_union_type:
      case DW_TAG_module:
        parent_type = read_type_die (parent, cu);
        if (TYPE_TAG_NAME (parent_type) != NULL)
          return TYPE_TAG_NAME (parent_type);
        else
          /* An anonymous structure is only allowed non-static data
             members; no typedefs, no member functions, et cetera.
             So it does not need a prefix.  */
          return "";
      default:
        return determine_prefix (parent, cu);
      }
}

/* Return a newly-allocated string formed by concatenating PREFIX and
   SUFFIX with appropriate separator.  If PREFIX or SUFFIX is NULL or empty, then
   simply copy the SUFFIX or PREFIX, respectively.  If OBS is non-null,
   perform an obconcat, otherwise allocate storage for the result.  The CU argument
   is used to determine the language and hence, the appropriate separator.  */

#define MAX_SEP_LEN 7  /* strlen ("__") + strlen ("_MOD_")  */

static char *
typename_concat (struct obstack *obs, const char *prefix, const char *suffix,
                 int physname, struct dwarf2_cu *cu)
{
  const char *lead = "";
  const char *sep;

  if (suffix == NULL || suffix[0] == '\0' || prefix == NULL || prefix[0] == '\0')
    sep = "";
  else if (cu->language == language_java)
    sep = ".";
  else if (cu->language == language_fortran && physname)
    {
      /* This is gfortran specific mangling.  Normally DW_AT_linkage_name or
         DW_AT_MIPS_linkage_name is preferred and used instead.  */

      lead = "__";
      sep = "_MOD_";
    }
  else
    sep = "::";

  if (prefix == NULL)
    prefix = "";
  if (suffix == NULL)
    suffix = "";

  if (obs == NULL)
    {
      char *retval = xmalloc (strlen (prefix) + MAX_SEP_LEN + strlen (suffix) + 1);

      strcpy (retval, lead);
      strcat (retval, prefix);
      strcat (retval, sep);
      strcat (retval, suffix);
      return retval;
    }
  else
    {
      /* We have an obstack.  */
      return obconcat (obs, lead, prefix, sep, suffix, (char *) NULL);
    }
}

/* Return sibling of die, NULL if no sibling.  */

static struct die_info *
sibling_die (struct die_info *die)
{
  return die->sibling;
}

/* Get name of a die, return NULL if not found.  */

static char *
dwarf2_canonicalize_name (char *name, struct dwarf2_cu *cu,
                          struct obstack *obstack)
{
  if (name && cu->language == language_cplus)
    {
      char *canon_name = cp_canonicalize_string (name);

      if (canon_name != NULL)
        {
          if (strcmp (canon_name, name) != 0)
            name = obsavestring (canon_name, strlen (canon_name),
                                 obstack);
          xfree (canon_name);
        }
    }

  return name;
}

/* Get name of a die, return NULL if not found.  */

static char *
dwarf2_name (struct die_info *die, struct dwarf2_cu *cu)
{
  struct attribute *attr;

  attr = dwarf2_attr (die, DW_AT_name, cu);
  if (!attr || !DW_STRING (attr))
    return NULL;

  switch (die->tag)
    {
    case DW_TAG_compile_unit:
      /* Compilation units have a DW_AT_name that is a filename, not
         a source language identifier.  */
    case DW_TAG_enumeration_type:
    case DW_TAG_enumerator:
      /* These tags always have simple identifiers already; no need
         to canonicalize them.  */
      return DW_STRING (attr);

    case DW_TAG_subprogram:
      /* Java constructors will all be named "<init>", so return
         the class name when we see this special case.  */
      if (cu->language == language_java
          && DW_STRING (attr) != NULL
          && strcmp (DW_STRING (attr), "<init>") == 0)
        {
          struct dwarf2_cu *spec_cu = cu;
          struct die_info *spec_die;

          /* GCJ will output '<init>' for Java constructor names.
             For this special case, return the name of the parent class.  */

          /* GCJ may output suprogram DIEs with AT_specification set.
             If so, use the name of the specified DIE.  */
          spec_die = die_specification (die, &spec_cu);
          if (spec_die != NULL)
            return dwarf2_name (spec_die, spec_cu);

          do
            {
              die = die->parent;
              if (die->tag == DW_TAG_class_type)
                return dwarf2_name (die, cu);
            }
          while (die->tag != DW_TAG_compile_unit);
        }
      break;

    case DW_TAG_class_type:
    case DW_TAG_interface_type:
    case DW_TAG_structure_type:
    case DW_TAG_union_type:
      /* Some GCC versions emit spurious DW_AT_name attributes for unnamed
         structures or unions.  These were of the form "._%d" in GCC 4.1,
         or simply "<anonymous struct>" or "<anonymous union>" in GCC 4.3
         and GCC 4.4.  We work around this problem by ignoring these.  */
      if (strncmp (DW_STRING (attr), "._", 2) == 0
          || strncmp (DW_STRING (attr), "<anonymous", 10) == 0)
        return NULL;
      break;

    default:
      break;
    }

  if (!DW_STRING_IS_CANONICAL (attr))
    {
      DW_STRING (attr)
        = dwarf2_canonicalize_name (DW_STRING (attr), cu,
                                    &cu->objfile->objfile_obstack);
      DW_STRING_IS_CANONICAL (attr) = 1;
    }
  return DW_STRING (attr);
}

/* Return the die that this die in an extension of, or NULL if there
   is none.  *EXT_CU is the CU containing DIE on input, and the CU
   containing the return value on output.  */

static struct die_info *
dwarf2_extension (struct die_info *die, struct dwarf2_cu **ext_cu)
{
  struct attribute *attr;

  attr = dwarf2_attr (die, DW_AT_extension, *ext_cu);
  if (attr == NULL)
    return NULL;

  return follow_die_ref (die, attr, ext_cu);
}

/* Convert a DIE tag into its string name.  */

static char *
dwarf_tag_name (unsigned tag)
{
  switch (tag)
    {
    case DW_TAG_padding:
      return "DW_TAG_padding";
    case DW_TAG_array_type:
      return "DW_TAG_array_type";
    case DW_TAG_class_type:
      return "DW_TAG_class_type";
    case DW_TAG_entry_point:
      return "DW_TAG_entry_point";
    case DW_TAG_enumeration_type:
      return "DW_TAG_enumeration_type";
    case DW_TAG_formal_parameter:
      return "DW_TAG_formal_parameter";
    case DW_TAG_imported_declaration:
      return "DW_TAG_imported_declaration";
    case DW_TAG_label:
      return "DW_TAG_label";
    case DW_TAG_lexical_block:
      return "DW_TAG_lexical_block";
    case DW_TAG_member:
      return "DW_TAG_member";
    case DW_TAG_pointer_type:
      return "DW_TAG_pointer_type";
    case DW_TAG_reference_type:
      return "DW_TAG_reference_type";
    case DW_TAG_compile_unit:
      return "DW_TAG_compile_unit";
    case DW_TAG_string_type:
      return "DW_TAG_string_type";
    case DW_TAG_structure_type:
      return "DW_TAG_structure_type";
    case DW_TAG_subroutine_type:
      return "DW_TAG_subroutine_type";
    case DW_TAG_typedef:
      return "DW_TAG_typedef";
    case DW_TAG_union_type:
      return "DW_TAG_union_type";
    case DW_TAG_unspecified_parameters:
      return "DW_TAG_unspecified_parameters";
    case DW_TAG_variant:
      return "DW_TAG_variant";
    case DW_TAG_common_block:
      return "DW_TAG_common_block";
    case DW_TAG_common_inclusion:
      return "DW_TAG_common_inclusion";
    case DW_TAG_inheritance:
      return "DW_TAG_inheritance";
    case DW_TAG_inlined_subroutine:
      return "DW_TAG_inlined_subroutine";
    case DW_TAG_module:
      return "DW_TAG_module";
    case DW_TAG_ptr_to_member_type:
      return "DW_TAG_ptr_to_member_type";
    case DW_TAG_set_type:
      return "DW_TAG_set_type";
    case DW_TAG_subrange_type:
      return "DW_TAG_subrange_type";
    case DW_TAG_with_stmt:
      return "DW_TAG_with_stmt";
    case DW_TAG_access_declaration:
      return "DW_TAG_access_declaration";
    case DW_TAG_base_type:
      return "DW_TAG_base_type";
    case DW_TAG_catch_block:
      return "DW_TAG_catch_block";
    case DW_TAG_const_type:
      return "DW_TAG_const_type";
    case DW_TAG_constant:
      return "DW_TAG_constant";
    case DW_TAG_enumerator:
      return "DW_TAG_enumerator";
    case DW_TAG_file_type:
      return "DW_TAG_file_type";
    case DW_TAG_friend:
      return "DW_TAG_friend";
    case DW_TAG_namelist:
      return "DW_TAG_namelist";
    case DW_TAG_namelist_item:
      return "DW_TAG_namelist_item";
    case DW_TAG_packed_type:
      return "DW_TAG_packed_type";
    case DW_TAG_subprogram:
      return "DW_TAG_subprogram";
    case DW_TAG_template_type_param:
      return "DW_TAG_template_type_param";
    case DW_TAG_template_value_param:
      return "DW_TAG_template_value_param";
    case DW_TAG_thrown_type:
      return "DW_TAG_thrown_type";
    case DW_TAG_try_block:
      return "DW_TAG_try_block";
    case DW_TAG_variant_part:
      return "DW_TAG_variant_part";
    case DW_TAG_variable:
      return "DW_TAG_variable";
    case DW_TAG_volatile_type:
      return "DW_TAG_volatile_type";
    case DW_TAG_dwarf_procedure:
      return "DW_TAG_dwarf_procedure";
    case DW_TAG_restrict_type:
      return "DW_TAG_restrict_type";
    case DW_TAG_interface_type:
      return "DW_TAG_interface_type";
    case DW_TAG_namespace:
      return "DW_TAG_namespace";
    case DW_TAG_imported_module:
      return "DW_TAG_imported_module";
    case DW_TAG_unspecified_type:
      return "DW_TAG_unspecified_type";
    case DW_TAG_partial_unit:
      return "DW_TAG_partial_unit";
    case DW_TAG_imported_unit:
      return "DW_TAG_imported_unit";
    case DW_TAG_condition:
      return "DW_TAG_condition";
    case DW_TAG_shared_type:
      return "DW_TAG_shared_type";
    case DW_TAG_type_unit:
      return "DW_TAG_type_unit";
    case DW_TAG_MIPS_loop:
      return "DW_TAG_MIPS_loop";
    case DW_TAG_HP_array_descriptor:
      return "DW_TAG_HP_array_descriptor";
    case DW_TAG_format_label:
      return "DW_TAG_format_label";
    case DW_TAG_function_template:
      return "DW_TAG_function_template";
    case DW_TAG_class_template:
      return "DW_TAG_class_template";
    case DW_TAG_GNU_BINCL:
      return "DW_TAG_GNU_BINCL";
    case DW_TAG_GNU_EINCL:
      return "DW_TAG_GNU_EINCL";
    case DW_TAG_upc_shared_type:
      return "DW_TAG_upc_shared_type";
    case DW_TAG_upc_strict_type:
      return "DW_TAG_upc_strict_type";
    case DW_TAG_upc_relaxed_type:
      return "DW_TAG_upc_relaxed_type";
    case DW_TAG_PGI_kanji_type:
      return "DW_TAG_PGI_kanji_type";
    case DW_TAG_PGI_interface_block:
      return "DW_TAG_PGI_interface_block";
    default:
      return "DW_TAG_<unknown>";
    }
}

/* Convert a DWARF attribute code into its string name.  */

static char *
dwarf_attr_name (unsigned attr)
{
  switch (attr)
    {
    case DW_AT_sibling:
      return "DW_AT_sibling";
    case DW_AT_location:
      return "DW_AT_location";
    case DW_AT_name:
      return "DW_AT_name";
    case DW_AT_ordering:
      return "DW_AT_ordering";
    case DW_AT_subscr_data:
      return "DW_AT_subscr_data";
    case DW_AT_byte_size:
      return "DW_AT_byte_size";
    case DW_AT_bit_offset:
      return "DW_AT_bit_offset";
    case DW_AT_bit_size:
      return "DW_AT_bit_size";
    case DW_AT_element_list:
      return "DW_AT_element_list";
    case DW_AT_stmt_list:
      return "DW_AT_stmt_list";
    case DW_AT_low_pc:
      return "DW_AT_low_pc";
    case DW_AT_high_pc:
      return "DW_AT_high_pc";
    case DW_AT_language:
      return "DW_AT_language";
    case DW_AT_member:
      return "DW_AT_member";
    case DW_AT_discr:
      return "DW_AT_discr";
    case DW_AT_discr_value:
      return "DW_AT_discr_value";
    case DW_AT_visibility:
      return "DW_AT_visibility";
    case DW_AT_import:
      return "DW_AT_import";
    case DW_AT_string_length:
      return "DW_AT_string_length";
    case DW_AT_common_reference:
      return "DW_AT_common_reference";
    case DW_AT_comp_dir:
      return "DW_AT_comp_dir";
    case DW_AT_const_value:
      return "DW_AT_const_value";
    case DW_AT_containing_type:
      return "DW_AT_containing_type";
    case DW_AT_default_value:
      return "DW_AT_default_value";
    case DW_AT_inline:
      return "DW_AT_inline";
    case DW_AT_is_optional:
      return "DW_AT_is_optional";
    case DW_AT_lower_bound:
      return "DW_AT_lower_bound";
    case DW_AT_producer:
      return "DW_AT_producer";
    case DW_AT_prototyped:
      return "DW_AT_prototyped";
    case DW_AT_return_addr:
      return "DW_AT_return_addr";
    case DW_AT_start_scope:
      return "DW_AT_start_scope";
    case DW_AT_bit_stride:
      return "DW_AT_bit_stride";
    case DW_AT_upper_bound:
      return "DW_AT_upper_bound";
    case DW_AT_abstract_origin:
      return "DW_AT_abstract_origin";
    case DW_AT_accessibility:
      return "DW_AT_accessibility";
    case DW_AT_address_class:
      return "DW_AT_address_class";
    case DW_AT_artificial:
      return "DW_AT_artificial";
    case DW_AT_base_types:
      return "DW_AT_base_types";
    case DW_AT_calling_convention:
      return "DW_AT_calling_convention";
    case DW_AT_count:
      return "DW_AT_count";
    case DW_AT_data_member_location:
      return "DW_AT_data_member_location";
    case DW_AT_decl_column:
      return "DW_AT_decl_column";
    case DW_AT_decl_file:
      return "DW_AT_decl_file";
    case DW_AT_decl_line:
      return "DW_AT_decl_line";
    case DW_AT_declaration:
      return "DW_AT_declaration";
    case DW_AT_discr_list:
      return "DW_AT_discr_list";
    case DW_AT_encoding:
      return "DW_AT_encoding";
    case DW_AT_external:
      return "DW_AT_external";
    case DW_AT_frame_base:
      return "DW_AT_frame_base";
    case DW_AT_friend:
      return "DW_AT_friend";
    case DW_AT_identifier_case:
      return "DW_AT_identifier_case";
    case DW_AT_macro_info:
      return "DW_AT_macro_info";
    case DW_AT_namelist_items:
      return "DW_AT_namelist_items";
    case DW_AT_priority:
      return "DW_AT_priority";
    case DW_AT_segment:
      return "DW_AT_segment";
    case DW_AT_specification:
      return "DW_AT_specification";
    case DW_AT_static_link:
      return "DW_AT_static_link";
    case DW_AT_type:
      return "DW_AT_type";
    case DW_AT_use_location:
      return "DW_AT_use_location";
    case DW_AT_variable_parameter:
      return "DW_AT_variable_parameter";
    case DW_AT_virtuality:
      return "DW_AT_virtuality";
    case DW_AT_vtable_elem_location:
      return "DW_AT_vtable_elem_location";
    /* DWARF 3 values.  */
    case DW_AT_allocated:
      return "DW_AT_allocated";
    case DW_AT_associated:
      return "DW_AT_associated";
    case DW_AT_data_location:
      return "DW_AT_data_location";
    case DW_AT_byte_stride:
      return "DW_AT_byte_stride";
    case DW_AT_entry_pc:
      return "DW_AT_entry_pc";
    case DW_AT_use_UTF8:
      return "DW_AT_use_UTF8";
    case DW_AT_extension:
      return "DW_AT_extension";
    case DW_AT_ranges:
      return "DW_AT_ranges";
    case DW_AT_trampoline:
      return "DW_AT_trampoline";
    case DW_AT_call_column:
      return "DW_AT_call_column";
    case DW_AT_call_file:
      return "DW_AT_call_file";
    case DW_AT_call_line:
      return "DW_AT_call_line";
    case DW_AT_description:
      return "DW_AT_description";
    case DW_AT_binary_scale:
      return "DW_AT_binary_scale";
    case DW_AT_decimal_scale:
      return "DW_AT_decimal_scale";
    case DW_AT_small:
      return "DW_AT_small";
    case DW_AT_decimal_sign:
      return "DW_AT_decimal_sign";
    case DW_AT_digit_count:
      return "DW_AT_digit_count";
    case DW_AT_picture_string:
      return "DW_AT_picture_string";
    case DW_AT_mutable:
      return "DW_AT_mutable";
    case DW_AT_threads_scaled:
      return "DW_AT_threads_scaled";
    case DW_AT_explicit:
      return "DW_AT_explicit";
    case DW_AT_object_pointer:
      return "DW_AT_object_pointer";
    case DW_AT_endianity:
      return "DW_AT_endianity";
    case DW_AT_elemental:
      return "DW_AT_elemental";
    case DW_AT_pure:
      return "DW_AT_pure";
    case DW_AT_recursive:
      return "DW_AT_recursive";
    /* DWARF 4 values.  */
    case DW_AT_signature:
      return "DW_AT_signature";
    case DW_AT_linkage_name:
      return "DW_AT_linkage_name";
    /* SGI/MIPS extensions.  */
#ifdef MIPS /* collides with DW_AT_HP_block_index */
    case DW_AT_MIPS_fde:
      return "DW_AT_MIPS_fde";
#endif
    case DW_AT_MIPS_loop_begin:
      return "DW_AT_MIPS_loop_begin";
    case DW_AT_MIPS_tail_loop_begin:
      return "DW_AT_MIPS_tail_loop_begin";
    case DW_AT_MIPS_epilog_begin:
      return "DW_AT_MIPS_epilog_begin";
    case DW_AT_MIPS_loop_unroll_factor:
      return "DW_AT_MIPS_loop_unroll_factor";
    case DW_AT_MIPS_software_pipeline_depth:
      return "DW_AT_MIPS_software_pipeline_depth";
    case DW_AT_MIPS_linkage_name:
      return "DW_AT_MIPS_linkage_name";
    case DW_AT_MIPS_stride:
      return "DW_AT_MIPS_stride";
    case DW_AT_MIPS_abstract_name:
      return "DW_AT_MIPS_abstract_name";
    case DW_AT_MIPS_clone_origin:
      return "DW_AT_MIPS_clone_origin";
    case DW_AT_MIPS_has_inlines:
      return "DW_AT_MIPS_has_inlines";
    /* HP extensions.  */
#ifndef MIPS /* collides with DW_AT_MIPS_fde */
    case DW_AT_HP_block_index:
      return "DW_AT_HP_block_index";
#endif
    case DW_AT_HP_unmodifiable:
      return "DW_AT_HP_unmodifiable";
    case DW_AT_HP_actuals_stmt_list:
      return "DW_AT_HP_actuals_stmt_list";
    case DW_AT_HP_proc_per_section:
      return "DW_AT_HP_proc_per_section";
    case DW_AT_HP_raw_data_ptr:
      return "DW_AT_HP_raw_data_ptr";
    case DW_AT_HP_pass_by_reference:
      return "DW_AT_HP_pass_by_reference";
    case DW_AT_HP_opt_level:
      return "DW_AT_HP_opt_level";
    case DW_AT_HP_prof_version_id:
      return "DW_AT_HP_prof_version_id";
    case DW_AT_HP_opt_flags:
      return "DW_AT_HP_opt_flags";
    case DW_AT_HP_cold_region_low_pc:
      return "DW_AT_HP_cold_region_low_pc";
    case DW_AT_HP_cold_region_high_pc:
      return "DW_AT_HP_cold_region_high_pc";
    case DW_AT_HP_all_variables_modifiable:
      return "DW_AT_HP_all_variables_modifiable";
    case DW_AT_HP_linkage_name:
      return "DW_AT_HP_linkage_name";
    case DW_AT_HP_prof_flags:
      return "DW_AT_HP_prof_flags";
    /* GNU extensions.  */
    case DW_AT_sf_names:
      return "DW_AT_sf_names";
    case DW_AT_src_info:
      return "DW_AT_src_info";
    case DW_AT_mac_info:
      return "DW_AT_mac_info";
    case DW_AT_src_coords:
      return "DW_AT_src_coords";
    case DW_AT_body_begin:
      return "DW_AT_body_begin";
    case DW_AT_body_end:
      return "DW_AT_body_end";
    case DW_AT_GNU_vector:
      return "DW_AT_GNU_vector";
    /* VMS extensions.  */
    case DW_AT_VMS_rtnbeg_pd_address:
      return "DW_AT_VMS_rtnbeg_pd_address";
    /* UPC extension.  */
    case DW_AT_upc_threads_scaled:
      return "DW_AT_upc_threads_scaled";
    /* PGI (STMicroelectronics) extensions.  */
    case DW_AT_PGI_lbase:
      return "DW_AT_PGI_lbase";
    case DW_AT_PGI_soffset:
      return "DW_AT_PGI_soffset";
    case DW_AT_PGI_lstride:
      return "DW_AT_PGI_lstride";
    default:
      return "DW_AT_<unknown>";
    }
}

/* Convert a DWARF value form code into its string name.  */

static char *
dwarf_form_name (unsigned form)
{
  switch (form)
    {
    case DW_FORM_addr:
      return "DW_FORM_addr";
    case DW_FORM_block2:
      return "DW_FORM_block2";
    case DW_FORM_block4:
      return "DW_FORM_block4";
    case DW_FORM_data2:
      return "DW_FORM_data2";
    case DW_FORM_data4:
      return "DW_FORM_data4";
    case DW_FORM_data8:
      return "DW_FORM_data8";
    case DW_FORM_string:
      return "DW_FORM_string";
    case DW_FORM_block:
      return "DW_FORM_block";
    case DW_FORM_block1:
      return "DW_FORM_block1";
    case DW_FORM_data1:
      return "DW_FORM_data1";
    case DW_FORM_flag:
      return "DW_FORM_flag";
    case DW_FORM_sdata:
      return "DW_FORM_sdata";
    case DW_FORM_strp:
      return "DW_FORM_strp";
    case DW_FORM_udata:
      return "DW_FORM_udata";
    case DW_FORM_ref_addr:
      return "DW_FORM_ref_addr";
    case DW_FORM_ref1:
      return "DW_FORM_ref1";
    case DW_FORM_ref2:
      return "DW_FORM_ref2";
    case DW_FORM_ref4:
      return "DW_FORM_ref4";
    case DW_FORM_ref8:
      return "DW_FORM_ref8";
    case DW_FORM_ref_udata:
      return "DW_FORM_ref_udata";
    case DW_FORM_indirect:
      return "DW_FORM_indirect";
    case DW_FORM_sec_offset:
      return "DW_FORM_sec_offset";
    case DW_FORM_exprloc:
      return "DW_FORM_exprloc";
    case DW_FORM_flag_present:
      return "DW_FORM_flag_present";
    case DW_FORM_sig8:
      return "DW_FORM_sig8";
    default:
      return "DW_FORM_<unknown>";
    }
}

/* Convert a DWARF stack opcode into its string name.  */

const char *
dwarf_stack_op_name (unsigned op, int def)
{
  switch (op)
    {
    case DW_OP_addr:
      return "DW_OP_addr";
    case DW_OP_deref:
      return "DW_OP_deref";
    case DW_OP_const1u:
      return "DW_OP_const1u";
    case DW_OP_const1s:
      return "DW_OP_const1s";
    case DW_OP_const2u:
      return "DW_OP_const2u";
    case DW_OP_const2s:
      return "DW_OP_const2s";
    case DW_OP_const4u:
      return "DW_OP_const4u";
    case DW_OP_const4s:
      return "DW_OP_const4s";
    case DW_OP_const8u:
      return "DW_OP_const8u";
    case DW_OP_const8s:
      return "DW_OP_const8s";
    case DW_OP_constu:
      return "DW_OP_constu";
    case DW_OP_consts:
      return "DW_OP_consts";
    case DW_OP_dup:
      return "DW_OP_dup";
    case DW_OP_drop:
      return "DW_OP_drop";
    case DW_OP_over:
      return "DW_OP_over";
    case DW_OP_pick:
      return "DW_OP_pick";
    case DW_OP_swap:
      return "DW_OP_swap";
    case DW_OP_rot:
      return "DW_OP_rot";
    case DW_OP_xderef:
      return "DW_OP_xderef";
    case DW_OP_abs:
      return "DW_OP_abs";
    case DW_OP_and:
      return "DW_OP_and";
    case DW_OP_div:
      return "DW_OP_div";
    case DW_OP_minus:
      return "DW_OP_minus";
    case DW_OP_mod:
      return "DW_OP_mod";
    case DW_OP_mul:
      return "DW_OP_mul";
    case DW_OP_neg:
      return "DW_OP_neg";
    case DW_OP_not:
      return "DW_OP_not";
    case DW_OP_or:
      return "DW_OP_or";
    case DW_OP_plus:
      return "DW_OP_plus";
    case DW_OP_plus_uconst:
      return "DW_OP_plus_uconst";
    case DW_OP_shl:
      return "DW_OP_shl";
    case DW_OP_shr:
      return "DW_OP_shr";
    case DW_OP_shra:
      return "DW_OP_shra";
    case DW_OP_xor:
      return "DW_OP_xor";
    case DW_OP_bra:
      return "DW_OP_bra";
    case DW_OP_eq:
      return "DW_OP_eq";
    case DW_OP_ge:
      return "DW_OP_ge";
    case DW_OP_gt:
      return "DW_OP_gt";
    case DW_OP_le:
      return "DW_OP_le";
    case DW_OP_lt:
      return "DW_OP_lt";
    case DW_OP_ne:
      return "DW_OP_ne";
    case DW_OP_skip:
      return "DW_OP_skip";
    case DW_OP_lit0:
      return "DW_OP_lit0";
    case DW_OP_lit1:
      return "DW_OP_lit1";
    case DW_OP_lit2:
      return "DW_OP_lit2";
    case DW_OP_lit3:
      return "DW_OP_lit3";
    case DW_OP_lit4:
      return "DW_OP_lit4";
    case DW_OP_lit5:
      return "DW_OP_lit5";
    case DW_OP_lit6:
      return "DW_OP_lit6";
    case DW_OP_lit7:
      return "DW_OP_lit7";
    case DW_OP_lit8:
      return "DW_OP_lit8";
    case DW_OP_lit9:
      return "DW_OP_lit9";
    case DW_OP_lit10:
      return "DW_OP_lit10";
    case DW_OP_lit11:
      return "DW_OP_lit11";
    case DW_OP_lit12:
      return "DW_OP_lit12";
    case DW_OP_lit13:
      return "DW_OP_lit13";
    case DW_OP_lit14:
      return "DW_OP_lit14";
    case DW_OP_lit15:
      return "DW_OP_lit15";
    case DW_OP_lit16:
      return "DW_OP_lit16";
    case DW_OP_lit17:
      return "DW_OP_lit17";
    case DW_OP_lit18:
      return "DW_OP_lit18";
    case DW_OP_lit19:
      return "DW_OP_lit19";
    case DW_OP_lit20:
      return "DW_OP_lit20";
    case DW_OP_lit21:
      return "DW_OP_lit21";
    case DW_OP_lit22:
      return "DW_OP_lit22";
    case DW_OP_lit23:
      return "DW_OP_lit23";
    case DW_OP_lit24:
      return "DW_OP_lit24";
    case DW_OP_lit25:
      return "DW_OP_lit25";
    case DW_OP_lit26:
      return "DW_OP_lit26";
    case DW_OP_lit27:
      return "DW_OP_lit27";
    case DW_OP_lit28:
      return "DW_OP_lit28";
    case DW_OP_lit29:
      return "DW_OP_lit29";
    case DW_OP_lit30:
      return "DW_OP_lit30";
    case DW_OP_lit31:
      return "DW_OP_lit31";
    case DW_OP_reg0:
      return "DW_OP_reg0";
    case DW_OP_reg1:
      return "DW_OP_reg1";
    case DW_OP_reg2:
      return "DW_OP_reg2";
    case DW_OP_reg3:
      return "DW_OP_reg3";
    case DW_OP_reg4:
      return "DW_OP_reg4";
    case DW_OP_reg5:
      return "DW_OP_reg5";
    case DW_OP_reg6:
      return "DW_OP_reg6";
    case DW_OP_reg7:
      return "DW_OP_reg7";
    case DW_OP_reg8:
      return "DW_OP_reg8";
    case DW_OP_reg9:
      return "DW_OP_reg9";
    case DW_OP_reg10:
      return "DW_OP_reg10";
    case DW_OP_reg11:
      return "DW_OP_reg11";
    case DW_OP_reg12:
      return "DW_OP_reg12";
    case DW_OP_reg13:
      return "DW_OP_reg13";
    case DW_OP_reg14:
      return "DW_OP_reg14";
    case DW_OP_reg15:
      return "DW_OP_reg15";
    case DW_OP_reg16:
      return "DW_OP_reg16";
    case DW_OP_reg17:
      return "DW_OP_reg17";
    case DW_OP_reg18:
      return "DW_OP_reg18";
    case DW_OP_reg19:
      return "DW_OP_reg19";
    case DW_OP_reg20:
      return "DW_OP_reg20";
    case DW_OP_reg21:
      return "DW_OP_reg21";
    case DW_OP_reg22:
      return "DW_OP_reg22";
    case DW_OP_reg23:
      return "DW_OP_reg23";
    case DW_OP_reg24:
      return "DW_OP_reg24";
    case DW_OP_reg25:
      return "DW_OP_reg25";
    case DW_OP_reg26:
      return "DW_OP_reg26";
    case DW_OP_reg27:
      return "DW_OP_reg27";
    case DW_OP_reg28:
      return "DW_OP_reg28";
    case DW_OP_reg29:
      return "DW_OP_reg29";
    case DW_OP_reg30:
      return "DW_OP_reg30";
    case DW_OP_reg31:
      return "DW_OP_reg31";
    case DW_OP_breg0:
      return "DW_OP_breg0";
    case DW_OP_breg1:
      return "DW_OP_breg1";
    case DW_OP_breg2:
      return "DW_OP_breg2";
    case DW_OP_breg3:
      return "DW_OP_breg3";
    case DW_OP_breg4:
      return "DW_OP_breg4";
    case DW_OP_breg5:
      return "DW_OP_breg5";
    case DW_OP_breg6:
      return "DW_OP_breg6";
    case DW_OP_breg7:
      return "DW_OP_breg7";
    case DW_OP_breg8:
      return "DW_OP_breg8";
    case DW_OP_breg9:
      return "DW_OP_breg9";
    case DW_OP_breg10:
      return "DW_OP_breg10";
    case DW_OP_breg11:
      return "DW_OP_breg11";
    case DW_OP_breg12:
      return "DW_OP_breg12";
    case DW_OP_breg13:
      return "DW_OP_breg13";
    case DW_OP_breg14:
      return "DW_OP_breg14";
    case DW_OP_breg15:
      return "DW_OP_breg15";
    case DW_OP_breg16:
      return "DW_OP_breg16";
    case DW_OP_breg17:
      return "DW_OP_breg17";
    case DW_OP_breg18:
      return "DW_OP_breg18";
    case DW_OP_breg19:
      return "DW_OP_breg19";
    case DW_OP_breg20:
      return "DW_OP_breg20";
    case DW_OP_breg21:
      return "DW_OP_breg21";
    case DW_OP_breg22:
      return "DW_OP_breg22";
    case DW_OP_breg23:
      return "DW_OP_breg23";
    case DW_OP_breg24:
      return "DW_OP_breg24";
    case DW_OP_breg25:
      return "DW_OP_breg25";
    case DW_OP_breg26:
      return "DW_OP_breg26";
    case DW_OP_breg27:
      return "DW_OP_breg27";
    case DW_OP_breg28:
      return "DW_OP_breg28";
    case DW_OP_breg29:
      return "DW_OP_breg29";
    case DW_OP_breg30:
      return "DW_OP_breg30";
    case DW_OP_breg31:
      return "DW_OP_breg31";
    case DW_OP_regx:
      return "DW_OP_regx";
    case DW_OP_fbreg:
      return "DW_OP_fbreg";
    case DW_OP_bregx:
      return "DW_OP_bregx";
    case DW_OP_piece:
      return "DW_OP_piece";
    case DW_OP_deref_size:
      return "DW_OP_deref_size";
    case DW_OP_xderef_size:
      return "DW_OP_xderef_size";
    case DW_OP_nop:
      return "DW_OP_nop";
    /* DWARF 3 extensions.  */
    case DW_OP_push_object_address:
      return "DW_OP_push_object_address";
    case DW_OP_call2:
      return "DW_OP_call2";
    case DW_OP_call4:
      return "DW_OP_call4";
    case DW_OP_call_ref:
      return "DW_OP_call_ref";
    case DW_OP_form_tls_address:
      return "DW_OP_form_tls_address";
    case DW_OP_call_frame_cfa:
      return "DW_OP_call_frame_cfa";
    case DW_OP_bit_piece:
      return "DW_OP_bit_piece";
    /* DWARF 4 extensions.  */
    case DW_OP_implicit_value:
      return "DW_OP_implicit_value";
    case DW_OP_stack_value:
      return "DW_OP_stack_value";
    /* GNU extensions.  */
    case DW_OP_GNU_push_tls_address:
      return "DW_OP_GNU_push_tls_address";
    case DW_OP_GNU_uninit:
      return "DW_OP_GNU_uninit";
    default:
      return def ? "OP_<unknown>" : NULL;
    }
}

static char *
dwarf_bool_name (unsigned mybool)
{
  if (mybool)
    return "TRUE";
  else
    return "FALSE";
}

/* Convert a DWARF type code into its string name.  */

static char *
dwarf_type_encoding_name (unsigned enc)
{
  switch (enc)
    {
    case DW_ATE_void:
      return "DW_ATE_void";
    case DW_ATE_address:
      return "DW_ATE_address";
    case DW_ATE_boolean:
      return "DW_ATE_boolean";
    case DW_ATE_complex_float:
      return "DW_ATE_complex_float";
    case DW_ATE_float:
      return "DW_ATE_float";
    case DW_ATE_signed:
      return "DW_ATE_signed";
    case DW_ATE_signed_char:
      return "DW_ATE_signed_char";
    case DW_ATE_unsigned:
      return "DW_ATE_unsigned";
    case DW_ATE_unsigned_char:
      return "DW_ATE_unsigned_char";
    /* DWARF 3.  */
    case DW_ATE_imaginary_float:
      return "DW_ATE_imaginary_float";
    case DW_ATE_packed_decimal:
      return "DW_ATE_packed_decimal";
    case DW_ATE_numeric_string:
      return "DW_ATE_numeric_string";
    case DW_ATE_edited:
      return "DW_ATE_edited";
    case DW_ATE_signed_fixed:
      return "DW_ATE_signed_fixed";
    case DW_ATE_unsigned_fixed:
      return "DW_ATE_unsigned_fixed";
    case DW_ATE_decimal_float:
      return "DW_ATE_decimal_float";
    /* DWARF 4.  */
    case DW_ATE_UTF:
      return "DW_ATE_UTF";
    /* HP extensions.  */
    case DW_ATE_HP_float80:
      return "DW_ATE_HP_float80";
    case DW_ATE_HP_complex_float80:
      return "DW_ATE_HP_complex_float80";
    case DW_ATE_HP_float128:
      return "DW_ATE_HP_float128";
    case DW_ATE_HP_complex_float128:
      return "DW_ATE_HP_complex_float128";
    case DW_ATE_HP_floathpintel:
      return "DW_ATE_HP_floathpintel";
    case DW_ATE_HP_imaginary_float80:
      return "DW_ATE_HP_imaginary_float80";
    case DW_ATE_HP_imaginary_float128:
      return "DW_ATE_HP_imaginary_float128";
    default:
      return "DW_ATE_<unknown>";
    }
}

/* Convert a DWARF call frame info operation to its string name. */

#if 0
static char *
dwarf_cfi_name (unsigned cfi_opc)
{
  switch (cfi_opc)
    {
    case DW_CFA_advance_loc:
      return "DW_CFA_advance_loc";
    case DW_CFA_offset:
      return "DW_CFA_offset";
    case DW_CFA_restore:
      return "DW_CFA_restore";
    case DW_CFA_nop:
      return "DW_CFA_nop";
    case DW_CFA_set_loc:
      return "DW_CFA_set_loc";
    case DW_CFA_advance_loc1:
      return "DW_CFA_advance_loc1";
    case DW_CFA_advance_loc2:
      return "DW_CFA_advance_loc2";
    case DW_CFA_advance_loc4:
      return "DW_CFA_advance_loc4";
    case DW_CFA_offset_extended:
      return "DW_CFA_offset_extended";
    case DW_CFA_restore_extended:
      return "DW_CFA_restore_extended";
    case DW_CFA_undefined:
      return "DW_CFA_undefined";
    case DW_CFA_same_value:
      return "DW_CFA_same_value";
    case DW_CFA_register:
      return "DW_CFA_register";
    case DW_CFA_remember_state:
      return "DW_CFA_remember_state";
    case DW_CFA_restore_state:
      return "DW_CFA_restore_state";
    case DW_CFA_def_cfa:
      return "DW_CFA_def_cfa";
    case DW_CFA_def_cfa_register:
      return "DW_CFA_def_cfa_register";
    case DW_CFA_def_cfa_offset:
      return "DW_CFA_def_cfa_offset";
    /* DWARF 3.  */
    case DW_CFA_def_cfa_expression:
      return "DW_CFA_def_cfa_expression";
    case DW_CFA_expression:
      return "DW_CFA_expression";
    case DW_CFA_offset_extended_sf:
      return "DW_CFA_offset_extended_sf";
    case DW_CFA_def_cfa_sf:
      return "DW_CFA_def_cfa_sf";
    case DW_CFA_def_cfa_offset_sf:
      return "DW_CFA_def_cfa_offset_sf";
    case DW_CFA_val_offset:
      return "DW_CFA_val_offset";
    case DW_CFA_val_offset_sf:
      return "DW_CFA_val_offset_sf";
    case DW_CFA_val_expression:
      return "DW_CFA_val_expression";
    /* SGI/MIPS specific.  */
    case DW_CFA_MIPS_advance_loc8:
      return "DW_CFA_MIPS_advance_loc8";
    /* GNU extensions.  */
    case DW_CFA_GNU_window_save:
      return "DW_CFA_GNU_window_save";
    case DW_CFA_GNU_args_size:
      return "DW_CFA_GNU_args_size";
    case DW_CFA_GNU_negative_offset_extended:
      return "DW_CFA_GNU_negative_offset_extended";
    default:
      return "DW_CFA_<unknown>";
    }
}
#endif

static void
dump_die_shallow (struct ui_file *f, int indent, struct die_info *die)
{
  unsigned int i;

  print_spaces (indent, f);
  fprintf_unfiltered (f, "Die: %s (abbrev %d, offset 0x%x)\n",
           dwarf_tag_name (die->tag), die->abbrev, die->offset);

  if (die->parent != NULL)
    {
      print_spaces (indent, f);
      fprintf_unfiltered (f, "  parent at offset: 0x%x\n",
                          die->parent->offset);
    }

  print_spaces (indent, f);
  fprintf_unfiltered (f, "  has children: %s\n",
           dwarf_bool_name (die->child != NULL));

  print_spaces (indent, f);
  fprintf_unfiltered (f, "  attributes:\n");

  for (i = 0; i < die->num_attrs; ++i)
    {
      print_spaces (indent, f);
      fprintf_unfiltered (f, "    %s (%s) ",
               dwarf_attr_name (die->attrs[i].name),
               dwarf_form_name (die->attrs[i].form));

      switch (die->attrs[i].form)
        {
        case DW_FORM_ref_addr:
        case DW_FORM_addr:
          fprintf_unfiltered (f, "address: ");
          fputs_filtered (hex_string (DW_ADDR (&die->attrs[i])), f);
          break;
        case DW_FORM_block2:
        case DW_FORM_block4:
        case DW_FORM_block:
        case DW_FORM_block1:
          fprintf_unfiltered (f, "block: size %d", DW_BLOCK (&die->attrs[i])->size);
          break;
        case DW_FORM_exprloc:
          fprintf_unfiltered (f, "expression: size %u",
                              DW_BLOCK (&die->attrs[i])->size);
          break;
        case DW_FORM_ref1:
        case DW_FORM_ref2:
        case DW_FORM_ref4:
          fprintf_unfiltered (f, "constant ref: 0x%lx (adjusted)",
                              (long) (DW_ADDR (&die->attrs[i])));
          break;
        case DW_FORM_data1:
        case DW_FORM_data2:
        case DW_FORM_data4:
        case DW_FORM_data8:
        case DW_FORM_udata:
        case DW_FORM_sdata:
          fprintf_unfiltered (f, "constant: %s",
                              pulongest (DW_UNSND (&die->attrs[i])));
          break;
        case DW_FORM_sec_offset:
          fprintf_unfiltered (f, "section offset: %s",
                              pulongest (DW_UNSND (&die->attrs[i])));
          break;
        case DW_FORM_sig8:
          if (DW_SIGNATURED_TYPE (&die->attrs[i]) != NULL)
            fprintf_unfiltered (f, "signatured type, offset: 0x%x",
                                DW_SIGNATURED_TYPE (&die->attrs[i])->offset);
          else
            fprintf_unfiltered (f, "signatured type, offset: unknown");
          break;
        case DW_FORM_string:
        case DW_FORM_strp:
          fprintf_unfiltered (f, "string: \"%s\" (%s canonicalized)",
                   DW_STRING (&die->attrs[i])
                   ? DW_STRING (&die->attrs[i]) : "",
                   DW_STRING_IS_CANONICAL (&die->attrs[i]) ? "is" : "not");
          break;
        case DW_FORM_flag:
          if (DW_UNSND (&die->attrs[i]))
            fprintf_unfiltered (f, "flag: TRUE");
          else
            fprintf_unfiltered (f, "flag: FALSE");
          break;
        case DW_FORM_flag_present:
          fprintf_unfiltered (f, "flag: TRUE");
          break;
        case DW_FORM_indirect:
          /* the reader will have reduced the indirect form to
             the "base form" so this form should not occur */
          fprintf_unfiltered (f, "unexpected attribute form: DW_FORM_indirect");
          break;
        default:
          fprintf_unfiltered (f, "unsupported attribute form: %d.",
                   die->attrs[i].form);
          break;
        }
      fprintf_unfiltered (f, "\n");
    }
}

static void
dump_die_for_error (struct die_info *die)
{
  dump_die_shallow (gdb_stderr, 0, die);
}

static void
dump_die_1 (struct ui_file *f, int level, int max_level, struct die_info *die)
{
  int indent = level * 4;

  gdb_assert (die != NULL);

  if (level >= max_level)
    return;

  dump_die_shallow (f, indent, die);

  if (die->child != NULL)
    {
      print_spaces (indent, f);
      fprintf_unfiltered (f, "  Children:");
      if (level + 1 < max_level)
        {
          fprintf_unfiltered (f, "\n");
          dump_die_1 (f, level + 1, max_level, die->child);
        }
      else
        {
          fprintf_unfiltered (f, " [not printed, max nesting level reached]\n");
        }
    }

  if (die->sibling != NULL && level > 0)
    {
      dump_die_1 (f, level, max_level, die->sibling);
    }
}

/* This is called from the pdie macro in gdbinit.in.
   It's not static so gcc will keep a copy callable from gdb.  */

void
dump_die (struct die_info *die, int max_level)
{
  dump_die_1 (gdb_stdlog, 0, max_level, die);
}

static void
store_in_ref_table (struct die_info *die, struct dwarf2_cu *cu)
{
  void **slot;

  slot = htab_find_slot_with_hash (cu->die_hash, die, die->offset, INSERT);

  *slot = die;
}

static int
is_ref_attr (struct attribute *attr)
{
  switch (attr->form)
    {
    case DW_FORM_ref_addr:
    case DW_FORM_ref1:
    case DW_FORM_ref2:
    case DW_FORM_ref4:
    case DW_FORM_ref8:
    case DW_FORM_ref_udata:
      return 1;
    default:
      return 0;
    }
}

static unsigned int
dwarf2_get_ref_die_offset (struct attribute *attr)
{
  if (is_ref_attr (attr))
    return DW_ADDR (attr);

  complaint (&symfile_complaints,
             _("unsupported die ref attribute form: '%s'"),
             dwarf_form_name (attr->form));
  return 0;
}

/* Return the constant value held by ATTR.  Return DEFAULT_VALUE if
 * the value held by the attribute is not constant.  */

static LONGEST
dwarf2_get_attr_constant_value (struct attribute *attr, int default_value)
{
  if (attr->form == DW_FORM_sdata)
    return DW_SND (attr);
  else if (attr->form == DW_FORM_udata
           || attr->form == DW_FORM_data1
           || attr->form == DW_FORM_data2
           || attr->form == DW_FORM_data4
           || attr->form == DW_FORM_data8)
    return DW_UNSND (attr);
  else
    {
      complaint (&symfile_complaints, _("Attribute value is not a constant (%s)"),
                 dwarf_form_name (attr->form));
      return default_value;
    }
}

/* THIS_CU has a reference to PER_CU.  If necessary, load the new compilation
   unit and add it to our queue.
   The result is non-zero if PER_CU was queued, otherwise the result is zero
   meaning either PER_CU is already queued or it is already loaded.  */

static int
maybe_queue_comp_unit (struct dwarf2_cu *this_cu,
                       struct dwarf2_per_cu_data *per_cu)
{
  /* Mark the dependence relation so that we don't flush PER_CU
     too early.  */
  dwarf2_add_dependence (this_cu, per_cu);

  /* If it's already on the queue, we have nothing to do.  */
  if (per_cu->queued)
    return 0;

  /* If the compilation unit is already loaded, just mark it as
     used.  */
  if (per_cu->cu != NULL)
    {
      per_cu->cu->last_used = 0;
      return 0;
    }

  /* Add it to the queue.  */
  queue_comp_unit (per_cu, this_cu->objfile);

  return 1;
}

/* Follow reference or signature attribute ATTR of SRC_DIE.
   On entry *REF_CU is the CU of SRC_DIE.
   On exit *REF_CU is the CU of the result.  */

static struct die_info *
follow_die_ref_or_sig (struct die_info *src_die, struct attribute *attr,
                       struct dwarf2_cu **ref_cu)
{
  struct die_info *die;

  if (is_ref_attr (attr))
    die = follow_die_ref (src_die, attr, ref_cu);
  else if (attr->form == DW_FORM_sig8)
    die = follow_die_sig (src_die, attr, ref_cu);
  else
    {
      dump_die_for_error (src_die);
      error (_("Dwarf Error: Expected reference attribute [in module %s]"),
             (*ref_cu)->objfile->name);
    }

  return die;
}

/* Follow reference OFFSET.
   On entry *REF_CU is the CU of source DIE referencing OFFSET.
   On exit *REF_CU is the CU of the result.  */

static struct die_info *
follow_die_offset (unsigned int offset, struct dwarf2_cu **ref_cu)
{
  struct die_info temp_die;
  struct dwarf2_cu *target_cu, *cu = *ref_cu;

  gdb_assert (cu->per_cu != NULL);

  if (cu->per_cu->from_debug_types)
    {
      /* .debug_types CUs cannot reference anything outside their CU.
         If they need to, they have to reference a signatured type via
         DW_FORM_sig8.  */
      if (! offset_in_cu_p (&cu->header, offset))
        return NULL;
      target_cu = cu;
    }
  else if (! offset_in_cu_p (&cu->header, offset))
    {
      struct dwarf2_per_cu_data *per_cu;

      per_cu = dwarf2_find_containing_comp_unit (offset, cu->objfile);

      /* If necessary, add it to the queue and load its DIEs.  */
      if (maybe_queue_comp_unit (cu, per_cu))
        load_full_comp_unit (per_cu, cu->objfile);

      target_cu = per_cu->cu;
    }
  else
    target_cu = cu;

  *ref_cu = target_cu;
  temp_die.offset = offset;
  return htab_find_with_hash (target_cu->die_hash, &temp_die, offset);
}

/* Follow reference attribute ATTR of SRC_DIE.
   On entry *REF_CU is the CU of SRC_DIE.
   On exit *REF_CU is the CU of the result.  */

static struct die_info *
follow_die_ref (struct die_info *src_die, struct attribute *attr,
                struct dwarf2_cu **ref_cu)
{
  unsigned int offset = dwarf2_get_ref_die_offset (attr);
  struct dwarf2_cu *cu = *ref_cu;
  struct die_info *die;

  die = follow_die_offset (offset, ref_cu);
  if (!die)
    error (_("Dwarf Error: Cannot find DIE at 0x%x referenced from DIE "
           "at 0x%x [in module %s]"),
           offset, src_die->offset, cu->objfile->name);

  return die;
}

/* Return DWARF block and its CU referenced by OFFSET at PER_CU.  Returned
   value is intended for DW_OP_call*.  */

struct dwarf2_locexpr_baton
dwarf2_fetch_die_location_block (unsigned int offset,
                                 struct dwarf2_per_cu_data *per_cu)
{
  struct dwarf2_cu *cu = per_cu->cu;
  struct die_info *die;
  struct attribute *attr;
  struct dwarf2_locexpr_baton retval;

  die = follow_die_offset (offset, &cu);
  if (!die)
    error (_("Dwarf Error: Cannot find DIE at 0x%x referenced in module %s"),
           offset, per_cu->cu->objfile->name);

  attr = dwarf2_attr (die, DW_AT_location, cu);
  if (!attr)
    {
      /* DWARF: "If there is no such attribute, then there is no effect.".  */

      retval.data = NULL;
      retval.size = 0;
    }
  else
    {
      if (!attr_form_is_block (attr))
        error (_("Dwarf Error: DIE at 0x%x referenced in module %s "
                 "is neither DW_FORM_block* nor DW_FORM_exprloc"),
               offset, per_cu->cu->objfile->name);

      retval.data = DW_BLOCK (attr)->data;
      retval.size = DW_BLOCK (attr)->size;
    }
  retval.per_cu = cu->per_cu;
  return retval;
}

/* Follow the signature attribute ATTR in SRC_DIE.
   On entry *REF_CU is the CU of SRC_DIE.
   On exit *REF_CU is the CU of the result.  */

static struct die_info *
follow_die_sig (struct die_info *src_die, struct attribute *attr,
                struct dwarf2_cu **ref_cu)
{
  struct objfile *objfile = (*ref_cu)->objfile;
  struct die_info temp_die;
  struct signatured_type *sig_type = DW_SIGNATURED_TYPE (attr);
  struct dwarf2_cu *sig_cu;
  struct die_info *die;

  /* sig_type will be NULL if the signatured type is missing from
     the debug info.  */
  if (sig_type == NULL)
    error (_("Dwarf Error: Cannot find signatured DIE referenced from DIE "
             "at 0x%x [in module %s]"),
           src_die->offset, objfile->name);

  /* If necessary, add it to the queue and load its DIEs.  */

  if (maybe_queue_comp_unit (*ref_cu, &sig_type->per_cu))
    read_signatured_type (objfile, sig_type);

  gdb_assert (sig_type->per_cu.cu != NULL);

  sig_cu = sig_type->per_cu.cu;
  temp_die.offset = sig_cu->header.offset + sig_type->type_offset;
  die = htab_find_with_hash (sig_cu->die_hash, &temp_die, temp_die.offset);
  if (die)
    {
      *ref_cu = sig_cu;
      return die;
    }

  error (_("Dwarf Error: Cannot find signatured DIE at 0x%x referenced from DIE "
         "at 0x%x [in module %s]"),
         sig_type->type_offset, src_die->offset, objfile->name);
}

/* Given an offset of a signatured type, return its signatured_type.  */

static struct signatured_type *
lookup_signatured_type_at_offset (struct objfile *objfile, unsigned int offset)
{
  gdb_byte *info_ptr = dwarf2_per_objfile->types.buffer + offset;
  unsigned int length, initial_length_size;
  unsigned int sig_offset;
  struct signatured_type find_entry, *type_sig;

  length = read_initial_length (objfile->obfd, info_ptr, &initial_length_size);
  sig_offset = (initial_length_size
                + 2 /*version*/
                + (initial_length_size == 4 ? 4 : 8) /*debug_abbrev_offset*/
                + 1 /*address_size*/);
  find_entry.signature = bfd_get_64 (objfile->obfd, info_ptr + sig_offset);
  type_sig = htab_find (dwarf2_per_objfile->signatured_types, &find_entry);

  /* This is only used to lookup previously recorded types.
     If we didn't find it, it's our bug.  */
  gdb_assert (type_sig != NULL);
  gdb_assert (offset == type_sig->offset);

  return type_sig;
}

/* Read in signatured type at OFFSET and build its CU and die(s).  */

static void
read_signatured_type_at_offset (struct objfile *objfile,
                                unsigned int offset)
{
  struct signatured_type *type_sig;

  dwarf2_read_section (objfile, &dwarf2_per_objfile->types);

  /* We have the section offset, but we need the signature to do the
     hash table lookup.  */
  type_sig = lookup_signatured_type_at_offset (objfile, offset);

  gdb_assert (type_sig->per_cu.cu == NULL);

  read_signatured_type (objfile, type_sig);

  gdb_assert (type_sig->per_cu.cu != NULL);
}

/* Read in a signatured type and build its CU and DIEs.  */

static void
read_signatured_type (struct objfile *objfile,
                      struct signatured_type *type_sig)
{
  gdb_byte *types_ptr = dwarf2_per_objfile->types.buffer + type_sig->offset;
  struct die_reader_specs reader_specs;
  struct dwarf2_cu *cu;
  ULONGEST signature;
  struct cleanup *back_to, *free_cu_cleanup;
  struct attribute *attr;

  gdb_assert (type_sig->per_cu.cu == NULL);

  cu = xmalloc (sizeof (struct dwarf2_cu));
  memset (cu, 0, sizeof (struct dwarf2_cu));
  obstack_init (&cu->comp_unit_obstack);
  cu->objfile = objfile;
  type_sig->per_cu.cu = cu;
  cu->per_cu = &type_sig->per_cu;

  /* If an error occurs while loading, release our storage.  */
  free_cu_cleanup = make_cleanup (free_one_comp_unit, cu);

  types_ptr = read_type_comp_unit_head (&cu->header, &signature,
                                        types_ptr, objfile->obfd);
  gdb_assert (signature == type_sig->signature);

  cu->die_hash
    = htab_create_alloc_ex (cu->header.length / 12,
                            die_hash,
                            die_eq,
                            NULL,
                            &cu->comp_unit_obstack,
                            hashtab_obstack_allocate,
                            dummy_obstack_deallocate);

  dwarf2_read_abbrevs (cu->objfile->obfd, cu);
  back_to = make_cleanup (dwarf2_free_abbrev_table, cu);

  init_cu_die_reader (&reader_specs, cu);

  cu->dies = read_die_and_children (&reader_specs, types_ptr, &types_ptr,
                                    NULL /*parent*/);

  /* We try not to read any attributes in this function, because not
     all objfiles needed for references have been loaded yet, and symbol
     table processing isn't initialized.  But we have to set the CU language,
     or we won't be able to build types correctly.  */
  attr = dwarf2_attr (cu->dies, DW_AT_language, cu);
  if (attr)
    set_cu_language (DW_UNSND (attr), cu);
  else
    set_cu_language (language_minimal, cu);

  do_cleanups (back_to);

  /* We've successfully allocated this compilation unit.  Let our caller
     clean it up when finished with it.  */
  discard_cleanups (free_cu_cleanup);

  type_sig->per_cu.cu->read_in_chain = dwarf2_per_objfile->read_in_chain;
  dwarf2_per_objfile->read_in_chain = &type_sig->per_cu;
}

/* Decode simple location descriptions.
   Given a pointer to a dwarf block that defines a location, compute
   the location and return the value.

   NOTE drow/2003-11-18: This function is called in two situations
   now: for the address of static or global variables (partial symbols
   only) and for offsets into structures which are expected to be
   (more or less) constant.  The partial symbol case should go away,
   and only the constant case should remain.  That will let this
   function complain more accurately.  A few special modes are allowed
   without complaint for global variables (for instance, global
   register values and thread-local values).

   A location description containing no operations indicates that the
   object is optimized out.  The return value is 0 for that case.
   FIXME drow/2003-11-16: No callers check for this case any more; soon all
   callers will only want a very basic result and this can become a
   complaint.

   Note that stack[0] is unused except as a default error return.
   Note that stack overflow is not yet handled.  */

static CORE_ADDR
decode_locdesc (struct dwarf_block *blk, struct dwarf2_cu *cu)
{
  struct objfile *objfile = cu->objfile;
  int i;
  int size = blk->size;
  gdb_byte *data = blk->data;
  CORE_ADDR stack[64];
  int stacki;
  unsigned int bytes_read, unsnd;
  gdb_byte op;

  i = 0;
  stacki = 0;
  stack[stacki] = 0;

  while (i < size)
    {
      op = data[i++];
      switch (op)
        {
        case DW_OP_lit0:
        case DW_OP_lit1:
        case DW_OP_lit2:
        case DW_OP_lit3:
        case DW_OP_lit4:
        case DW_OP_lit5:
        case DW_OP_lit6:
        case DW_OP_lit7:
        case DW_OP_lit8:
        case DW_OP_lit9:
        case DW_OP_lit10:
        case DW_OP_lit11:
        case DW_OP_lit12:
        case DW_OP_lit13:
        case DW_OP_lit14:
        case DW_OP_lit15:
        case DW_OP_lit16:
        case DW_OP_lit17:
        case DW_OP_lit18:
        case DW_OP_lit19:
        case DW_OP_lit20:
        case DW_OP_lit21:
        case DW_OP_lit22:
        case DW_OP_lit23:
        case DW_OP_lit24:
        case DW_OP_lit25:
        case DW_OP_lit26:
        case DW_OP_lit27:
        case DW_OP_lit28:
        case DW_OP_lit29:
        case DW_OP_lit30:
        case DW_OP_lit31:
          stack[++stacki] = op - DW_OP_lit0;
          break;

        case DW_OP_reg0:
        case DW_OP_reg1:
        case DW_OP_reg2:
        case DW_OP_reg3:
        case DW_OP_reg4:
        case DW_OP_reg5:
        case DW_OP_reg6:
        case DW_OP_reg7:
        case DW_OP_reg8:
        case DW_OP_reg9:
        case DW_OP_reg10:
        case DW_OP_reg11:
        case DW_OP_reg12:
        case DW_OP_reg13:
        case DW_OP_reg14:
        case DW_OP_reg15:
        case DW_OP_reg16:
        case DW_OP_reg17:
        case DW_OP_reg18:
        case DW_OP_reg19:
        case DW_OP_reg20:
        case DW_OP_reg21:
        case DW_OP_reg22:
        case DW_OP_reg23:
        case DW_OP_reg24:
        case DW_OP_reg25:
        case DW_OP_reg26:
        case DW_OP_reg27:
        case DW_OP_reg28:
        case DW_OP_reg29:
        case DW_OP_reg30:
        case DW_OP_reg31:
          stack[++stacki] = op - DW_OP_reg0;
          if (i < size)
            dwarf2_complex_location_expr_complaint ();
          break;

        case DW_OP_regx:
          unsnd = read_unsigned_leb128 (NULL, (data + i), &bytes_read);
          i += bytes_read;
          stack[++stacki] = unsnd;
          if (i < size)
            dwarf2_complex_location_expr_complaint ();
          break;

        case DW_OP_addr:
          stack[++stacki] = read_address (objfile->obfd, &data[i],
                                          cu, &bytes_read);
          i += bytes_read;
          break;

        case DW_OP_const1u:
          stack[++stacki] = read_1_byte (objfile->obfd, &data[i]);
          i += 1;
          break;

        case DW_OP_const1s:
          stack[++stacki] = read_1_signed_byte (objfile->obfd, &data[i]);
          i += 1;
          break;

        case DW_OP_const2u:
          stack[++stacki] = read_2_bytes (objfile->obfd, &data[i]);
          i += 2;
          break;

        case DW_OP_const2s:
          stack[++stacki] = read_2_signed_bytes (objfile->obfd, &data[i]);
          i += 2;
          break;

        case DW_OP_const4u:
          stack[++stacki] = read_4_bytes (objfile->obfd, &data[i]);
          i += 4;
          break;

        case DW_OP_const4s:
          stack[++stacki] = read_4_signed_bytes (objfile->obfd, &data[i]);
          i += 4;
          break;

        case DW_OP_constu:
          stack[++stacki] = read_unsigned_leb128 (NULL, (data + i),
                                                  &bytes_read);
          i += bytes_read;
          break;

        case DW_OP_consts:
          stack[++stacki] = read_signed_leb128 (NULL, (data + i), &bytes_read);
          i += bytes_read;
          break;

        case DW_OP_dup:
          stack[stacki + 1] = stack[stacki];
          stacki++;
          break;

        case DW_OP_plus:
          stack[stacki - 1] += stack[stacki];
          stacki--;
          break;

        case DW_OP_plus_uconst:
          stack[stacki] += read_unsigned_leb128 (NULL, (data + i), &bytes_read);
          i += bytes_read;
          break;

        case DW_OP_minus:
          stack[stacki - 1] -= stack[stacki];
          stacki--;
          break;

        case DW_OP_deref:
          /* If we're not the last op, then we definitely can't encode
             this using GDB's address_class enum.  This is valid for partial
             global symbols, although the variable's address will be bogus
             in the psymtab.  */
          if (i < size)
            dwarf2_complex_location_expr_complaint ();
          break;

        case DW_OP_GNU_push_tls_address:
          /* The top of the stack has the offset from the beginning
             of the thread control block at which the variable is located.  */
          /* Nothing should follow this operator, so the top of stack would
             be returned.  */
          /* This is valid for partial global symbols, but the variable's
             address will be bogus in the psymtab.  */
          if (i < size)
            dwarf2_complex_location_expr_complaint ();
          break;

        case DW_OP_GNU_uninit:
          break;

        default:
          complaint (&symfile_complaints, _("unsupported stack op: '%s'"),
                     dwarf_stack_op_name (op, 1));
          return (stack[stacki]);
        }
    }
  return (stack[stacki]);
}

/* memory allocation interface */

static struct dwarf_block *
dwarf_alloc_block (struct dwarf2_cu *cu)
{
  struct dwarf_block *blk;

  blk = (struct dwarf_block *)
    obstack_alloc (&cu->comp_unit_obstack, sizeof (struct dwarf_block));
  return (blk);
}

static struct abbrev_info *
dwarf_alloc_abbrev (struct dwarf2_cu *cu)
{
  struct abbrev_info *abbrev;

  abbrev = (struct abbrev_info *)
    obstack_alloc (&cu->abbrev_obstack, sizeof (struct abbrev_info));
  memset (abbrev, 0, sizeof (struct abbrev_info));
  return (abbrev);
}

static struct die_info *
dwarf_alloc_die (struct dwarf2_cu *cu, int num_attrs)
{
  struct die_info *die;
  size_t size = sizeof (struct die_info);

  if (num_attrs > 1)
    size += (num_attrs - 1) * sizeof (struct attribute);

  die = (struct die_info *) obstack_alloc (&cu->comp_unit_obstack, size);
  memset (die, 0, sizeof (struct die_info));
  return (die);
}

\f
/* Macro support.  */


/* Return the full name of file number I in *LH's file name table.
   Use COMP_DIR as the name of the current directory of the
   compilation.  The result is allocated using xmalloc; the caller is
   responsible for freeing it.  */
static char *
file_full_name (int file, struct line_header *lh, const char *comp_dir)
{
  /* Is the file number a valid index into the line header's file name
     table?  Remember that file numbers start with one, not zero.  */
  if (1 <= file && file <= lh->num_file_names)
    {
      struct file_entry *fe = &lh->file_names[file - 1];

      if (IS_ABSOLUTE_PATH (fe->name))
        return xstrdup (fe->name);
      else
        {
          const char *dir;
          int dir_len;
          char *full_name;

          if (fe->dir_index)
            dir = lh->include_dirs[fe->dir_index - 1];
          else
            dir = comp_dir;

          if (dir)
            {
              dir_len = strlen (dir);
              full_name = xmalloc (dir_len + 1 + strlen (fe->name) + 1);
              strcpy (full_name, dir);
              full_name[dir_len] = '/';
              strcpy (full_name + dir_len + 1, fe->name);
              return full_name;
            }
          else
            return xstrdup (fe->name);
        }
    }
  else
    {
      /* The compiler produced a bogus file number.  We can at least
         record the macro definitions made in the file, even if we
         won't be able to find the file by name.  */
      char fake_name[80];

      sprintf (fake_name, "<bad macro file number %d>", file);

      complaint (&symfile_complaints,
                 _("bad file number in macro information (%d)"),
                 file);

      return xstrdup (fake_name);
    }
}


static struct macro_source_file *
macro_start_file (int file, int line,
                  struct macro_source_file *current_file,
                  const char *comp_dir,
                  struct line_header *lh, struct objfile *objfile)
{
  /* The full name of this source file.  */
  char *full_name = file_full_name (file, lh, comp_dir);

  /* We don't create a macro table for this compilation unit
     at all until we actually get a filename.  */
  if (! pending_macros)
    pending_macros = new_macro_table (&objfile->objfile_obstack,
                                      objfile->macro_cache);

  if (! current_file)
    /* If we have no current file, then this must be the start_file
       directive for the compilation unit's main source file.  */
    current_file = macro_set_main (pending_macros, full_name);
  else
    current_file = macro_include (current_file, line, full_name);

  xfree (full_name);

  return current_file;
}


/* Copy the LEN characters at BUF to a xmalloc'ed block of memory,
   followed by a null byte.  */
static char *
copy_string (const char *buf, int len)
{
  char *s = xmalloc (len + 1);

  memcpy (s, buf, len);
  s[len] = '\0';
  return s;
}


static const char *
consume_improper_spaces (const char *p, const char *body)
{
  if (*p == ' ')
    {
      complaint (&symfile_complaints,
                 _("macro definition contains spaces in formal argument list:\n`%s'"),
                 body);

      while (*p == ' ')
        p++;
    }

  return p;
}


static void
parse_macro_definition (struct macro_source_file *file, int line,
                        const char *body)
{
  const char *p;

  /* The body string takes one of two forms.  For object-like macro
     definitions, it should be:

        <macro name> " " <definition>

     For function-like macro definitions, it should be:

        <macro name> "() " <definition>
     or
        <macro name> "(" <arg name> ( "," <arg name> ) * ") " <definition>

     Spaces may appear only where explicitly indicated, and in the
     <definition>.

     The Dwarf 2 spec says that an object-like macro's name is always
     followed by a space, but versions of GCC around March 2002 omit
     the space when the macro's definition is the empty string.

     The Dwarf 2 spec says that there should be no spaces between the
     formal arguments in a function-like macro's formal argument list,
     but versions of GCC around March 2002 include spaces after the
     commas.  */


  /* Find the extent of the macro name.  The macro name is terminated
     by either a space or null character (for an object-like macro) or
     an opening paren (for a function-like macro).  */
  for (p = body; *p; p++)
    if (*p == ' ' || *p == '(')
      break;

  if (*p == ' ' || *p == '\0')
    {
      /* It's an object-like macro.  */
      int name_len = p - body;
      char *name = copy_string (body, name_len);
      const char *replacement;

      if (*p == ' ')
        replacement = body + name_len + 1;
      else
        {
          dwarf2_macro_malformed_definition_complaint (body);
          replacement = body + name_len;
        }

      macro_define_object (file, line, name, replacement);

      xfree (name);
    }
  else if (*p == '(')
    {
      /* It's a function-like macro.  */
      char *name = copy_string (body, p - body);
      int argc = 0;
      int argv_size = 1;
      char **argv = xmalloc (argv_size * sizeof (*argv));

      p++;

      p = consume_improper_spaces (p, body);

      /* Parse the formal argument list.  */
      while (*p && *p != ')')
        {
          /* Find the extent of the current argument name.  */
          const char *arg_start = p;

          while (*p && *p != ',' && *p != ')' && *p != ' ')
            p++;

          if (! *p || p == arg_start)
            dwarf2_macro_malformed_definition_complaint (body);
          else
            {
              /* Make sure argv has room for the new argument.  */
              if (argc >= argv_size)
                {
                  argv_size *= 2;
                  argv = xrealloc (argv, argv_size * sizeof (*argv));
                }

              argv[argc++] = copy_string (arg_start, p - arg_start);
            }

          p = consume_improper_spaces (p, body);

          /* Consume the comma, if present.  */
          if (*p == ',')
            {
              p++;

              p = consume_improper_spaces (p, body);
            }
        }

      if (*p == ')')
        {
          p++;

          if (*p == ' ')
            /* Perfectly formed definition, no complaints.  */
            macro_define_function (file, line, name,
                                   argc, (const char **) argv,
                                   p + 1);
          else if (*p == '\0')
            {
              /* Complain, but do define it.  */
              dwarf2_macro_malformed_definition_complaint (body);
              macro_define_function (file, line, name,
                                     argc, (const char **) argv,
                                     p);
            }
          else
            /* Just complain.  */
            dwarf2_macro_malformed_definition_complaint (body);
        }
      else
        /* Just complain.  */
        dwarf2_macro_malformed_definition_complaint (body);

      xfree (name);
      {
        int i;

        for (i = 0; i < argc; i++)
          xfree (argv[i]);
      }
      xfree (argv);
    }
  else
    dwarf2_macro_malformed_definition_complaint (body);
}


static void
dwarf_decode_macros (struct line_header *lh, unsigned int offset,
                     char *comp_dir, bfd *abfd,
                     struct dwarf2_cu *cu)
{
  gdb_byte *mac_ptr, *mac_end;
  struct macro_source_file *current_file = 0;
  enum dwarf_macinfo_record_type macinfo_type;
  int at_commandline;

  dwarf2_read_section (dwarf2_per_objfile->objfile,
                       &dwarf2_per_objfile->macinfo);
  if (dwarf2_per_objfile->macinfo.buffer == NULL)
    {
      complaint (&symfile_complaints, _("missing .debug_macinfo section"));
      return;
    }

  /* First pass: Find the name of the base filename.
     This filename is needed in order to process all macros whose definition
     (or undefinition) comes from the command line.  These macros are defined
     before the first DW_MACINFO_start_file entry, and yet still need to be
     associated to the base file.

     To determine the base file name, we scan the macro definitions until we
     reach the first DW_MACINFO_start_file entry.  We then initialize
     CURRENT_FILE accordingly so that any macro definition found before the
     first DW_MACINFO_start_file can still be associated to the base file.  */

  mac_ptr = dwarf2_per_objfile->macinfo.buffer + offset;
  mac_end = dwarf2_per_objfile->macinfo.buffer
    + dwarf2_per_objfile->macinfo.size;

  do
    {
      /* Do we at least have room for a macinfo type byte?  */
      if (mac_ptr >= mac_end)
        {
          /* Complaint is printed during the second pass as GDB will probably
             stop the first pass earlier upon finding DW_MACINFO_start_file.  */
          break;
        }

      macinfo_type = read_1_byte (abfd, mac_ptr);
      mac_ptr++;

      switch (macinfo_type)
        {
          /* A zero macinfo type indicates the end of the macro
             information.  */
        case 0:
          break;

        case DW_MACINFO_define:
        case DW_MACINFO_undef:
          /* Only skip the data by MAC_PTR.  */
          {
            unsigned int bytes_read;

            read_unsigned_leb128 (abfd, mac_ptr, &bytes_read);
            mac_ptr += bytes_read;
            read_string (abfd, mac_ptr, &bytes_read);
            mac_ptr += bytes_read;
          }
          break;

        case DW_MACINFO_start_file:
          {
            unsigned int bytes_read;
            int line, file;

            line = read_unsigned_leb128 (abfd, mac_ptr, &bytes_read);
            mac_ptr += bytes_read;
            file = read_unsigned_leb128 (abfd, mac_ptr, &bytes_read);
            mac_ptr += bytes_read;

            current_file = macro_start_file (file, line, current_file, comp_dir,
                                             lh, cu->objfile);
          }
          break;

        case DW_MACINFO_end_file:
          /* No data to skip by MAC_PTR.  */
          break;

        case DW_MACINFO_vendor_ext:
          /* Only skip the data by MAC_PTR.  */
          {
            unsigned int bytes_read;

            read_unsigned_leb128 (abfd, mac_ptr, &bytes_read);
            mac_ptr += bytes_read;
            read_string (abfd, mac_ptr, &bytes_read);
            mac_ptr += bytes_read;
          }
          break;

        default:
          break;
        }
    } while (macinfo_type != 0 && current_file == NULL);

  /* Second pass: Process all entries.

     Use the AT_COMMAND_LINE flag to determine whether we are still processing
     command-line macro definitions/undefinitions.  This flag is unset when we
     reach the first DW_MACINFO_start_file entry.  */

  mac_ptr = dwarf2_per_objfile->macinfo.buffer + offset;

  /* Determines if GDB is still before first DW_MACINFO_start_file.  If true
     GDB is still reading the definitions from command line.  First
     DW_MACINFO_start_file will need to be ignored as it was already executed
     to create CURRENT_FILE for the main source holding also the command line
     definitions.  On first met DW_MACINFO_start_file this flag is reset to
     normally execute all the remaining DW_MACINFO_start_file macinfos.  */

  at_commandline = 1;

  do
    {
      /* Do we at least have room for a macinfo type byte?  */
      if (mac_ptr >= mac_end)
        {
          dwarf2_macros_too_long_complaint ();
          break;
        }

      macinfo_type = read_1_byte (abfd, mac_ptr);
      mac_ptr++;

      switch (macinfo_type)
        {
          /* A zero macinfo type indicates the end of the macro
             information.  */
        case 0:
          break;

        case DW_MACINFO_define:
        case DW_MACINFO_undef:
          {
            unsigned int bytes_read;
            int line;
            char *body;

            line = read_unsigned_leb128 (abfd, mac_ptr, &bytes_read);
            mac_ptr += bytes_read;
            body = read_string (abfd, mac_ptr, &bytes_read);
            mac_ptr += bytes_read;

            if (! current_file)
              {
                /* DWARF violation as no main source is present.  */
                complaint (&symfile_complaints,
                           _("debug info with no main source gives macro %s "
                             "on line %d: %s"),
                           macinfo_type == DW_MACINFO_define ?
                             _("definition") :
                               macinfo_type == DW_MACINFO_undef ?
                                 _("undefinition") :
                                 _("something-or-other"), line, body);
                break;
              }
            if ((line == 0 && !at_commandline) || (line != 0 && at_commandline))
              complaint (&symfile_complaints,
                         _("debug info gives %s macro %s with %s line %d: %s"),
                         at_commandline ? _("command-line") : _("in-file"),
                         macinfo_type == DW_MACINFO_define ?
                           _("definition") :
                             macinfo_type == DW_MACINFO_undef ?
                               _("undefinition") :
                               _("something-or-other"),
                         line == 0 ? _("zero") : _("non-zero"), line, body);

            if (macinfo_type == DW_MACINFO_define)
              parse_macro_definition (current_file, line, body);
            else if (macinfo_type == DW_MACINFO_undef)
              macro_undef (current_file, line, body);
          }
          break;

        case DW_MACINFO_start_file:
          {
            unsigned int bytes_read;
            int line, file;

            line = read_unsigned_leb128 (abfd, mac_ptr, &bytes_read);
            mac_ptr += bytes_read;
            file = read_unsigned_leb128 (abfd, mac_ptr, &bytes_read);
            mac_ptr += bytes_read;

            if ((line == 0 && !at_commandline) || (line != 0 && at_commandline))
              complaint (&symfile_complaints,
                         _("debug info gives source %d included "
                           "from %s at %s line %d"),
                         file, at_commandline ? _("command-line") : _("file"),
                         line == 0 ? _("zero") : _("non-zero"), line);

            if (at_commandline)
              {
                /* This DW_MACINFO_start_file was executed in the pass one.  */
                at_commandline = 0;
              }
            else
              current_file = macro_start_file (file, line,
                                               current_file, comp_dir,
                                               lh, cu->objfile);
          }
          break;

        case DW_MACINFO_end_file:
          if (! current_file)
            complaint (&symfile_complaints,
                       _("macro debug info has an unmatched `close_file' directive"));
          else
            {
              current_file = current_file->included_by;
              if (! current_file)
                {
                  enum dwarf_macinfo_record_type next_type;

                  /* GCC circa March 2002 doesn't produce the zero
                     type byte marking the end of the compilation
                     unit.  Complain if it's not there, but exit no
                     matter what.  */

                  /* Do we at least have room for a macinfo type byte?  */
                  if (mac_ptr >= mac_end)
                    {
                      dwarf2_macros_too_long_complaint ();
                      return;
                    }

                  /* We don't increment mac_ptr here, so this is just
                     a look-ahead.  */
                  next_type = read_1_byte (abfd, mac_ptr);
                  if (next_type != 0)
                    complaint (&symfile_complaints,
                               _("no terminating 0-type entry for macros in `.debug_macinfo' section"));

                  return;
                }
            }
          break;

        case DW_MACINFO_vendor_ext:
          {
            unsigned int bytes_read;
            int constant;
            char *string;

            constant = read_unsigned_leb128 (abfd, mac_ptr, &bytes_read);
            mac_ptr += bytes_read;
            string = read_string (abfd, mac_ptr, &bytes_read);
            mac_ptr += bytes_read;

            /* We don't recognize any vendor extensions.  */
          }
          break;
        }
    } while (macinfo_type != 0);
}

/* Check if the attribute's form is a DW_FORM_block*
   if so return true else false. */
static int
attr_form_is_block (struct attribute *attr)
{
  return (attr == NULL ? 0 :
      attr->form == DW_FORM_block1
      || attr->form == DW_FORM_block2
      || attr->form == DW_FORM_block4
      || attr->form == DW_FORM_block
      || attr->form == DW_FORM_exprloc);
}

/* Return non-zero if ATTR's value is a section offset --- classes
   lineptr, loclistptr, macptr or rangelistptr --- or zero, otherwise.
   You may use DW_UNSND (attr) to retrieve such offsets.

   Section 7.5.4, "Attribute Encodings", explains that no attribute
   may have a value that belongs to more than one of these classes; it
   would be ambiguous if we did, because we use the same forms for all
   of them.  */
static int
attr_form_is_section_offset (struct attribute *attr)
{
  return (attr->form == DW_FORM_data4
          || attr->form == DW_FORM_data8
          || attr->form == DW_FORM_sec_offset);
}


/* Return non-zero if ATTR's value falls in the 'constant' class, or
   zero otherwise.  When this function returns true, you can apply
   dwarf2_get_attr_constant_value to it.

   However, note that for some attributes you must check
   attr_form_is_section_offset before using this test.  DW_FORM_data4
   and DW_FORM_data8 are members of both the constant class, and of
   the classes that contain offsets into other debug sections
   (lineptr, loclistptr, macptr or rangelistptr).  The DWARF spec says
   that, if an attribute's can be either a constant or one of the
   section offset classes, DW_FORM_data4 and DW_FORM_data8 should be
   taken as section offsets, not constants.  */
static int
attr_form_is_constant (struct attribute *attr)
{
  switch (attr->form)
    {
    case DW_FORM_sdata:
    case DW_FORM_udata:
    case DW_FORM_data1:
    case DW_FORM_data2:
    case DW_FORM_data4:
    case DW_FORM_data8:
      return 1;
    default:
      return 0;
    }
}

static void
dwarf2_symbol_mark_computed (struct attribute *attr, struct symbol *sym,
                             struct dwarf2_cu *cu)
{
  if (attr_form_is_section_offset (attr)
      /* ".debug_loc" may not exist at all, or the offset may be outside
         the section.  If so, fall through to the complaint in the
         other branch.  */
      && DW_UNSND (attr) < dwarf2_per_objfile->loc.size)
    {
      struct dwarf2_loclist_baton *baton;

      baton = obstack_alloc (&cu->objfile->objfile_obstack,
                             sizeof (struct dwarf2_loclist_baton));
      baton->per_cu = cu->per_cu;
      gdb_assert (baton->per_cu);

      dwarf2_read_section (dwarf2_per_objfile->objfile,
                           &dwarf2_per_objfile->loc);

      /* We don't know how long the location list is, but make sure we
         don't run off the edge of the section.  */
      baton->size = dwarf2_per_objfile->loc.size - DW_UNSND (attr);
      baton->data = dwarf2_per_objfile->loc.buffer + DW_UNSND (attr);
      baton->base_address = cu->base_address;
      if (cu->base_known == 0)
        complaint (&symfile_complaints,
                   _("Location list used without specifying the CU base address."));

      SYMBOL_COMPUTED_OPS (sym) = &dwarf2_loclist_funcs;
      SYMBOL_LOCATION_BATON (sym) = baton;
    }
  else
    {
      struct dwarf2_locexpr_baton *baton;

      baton = obstack_alloc (&cu->objfile->objfile_obstack,
                             sizeof (struct dwarf2_locexpr_baton));
      baton->per_cu = cu->per_cu;
      gdb_assert (baton->per_cu);

      if (attr_form_is_block (attr))
        {
          /* Note that we're just copying the block's data pointer
             here, not the actual data.  We're still pointing into the
             info_buffer for SYM's objfile; right now we never release
             that buffer, but when we do clean up properly this may
             need to change.  */
          baton->size = DW_BLOCK (attr)->size;
          baton->data = DW_BLOCK (attr)->data;
        }
      else
        {
          dwarf2_invalid_attrib_class_complaint ("location description",
                                                 SYMBOL_NATURAL_NAME (sym));
          baton->size = 0;
          baton->data = NULL;
        }

      SYMBOL_COMPUTED_OPS (sym) = &dwarf2_locexpr_funcs;
      SYMBOL_LOCATION_BATON (sym) = baton;
    }
}

/* Return the OBJFILE associated with the compilation unit CU.  If CU
   came from a separate debuginfo file, then the master objfile is
   returned.  */

struct objfile *
dwarf2_per_cu_objfile (struct dwarf2_per_cu_data *per_cu)
{
  struct objfile *objfile = per_cu->objfile;

  /* Return the master objfile, so that we can report and look up the
     correct file containing this variable.  */
  if (objfile->separate_debug_objfile_backlink)
    objfile = objfile->separate_debug_objfile_backlink;

  return objfile;
}

/* Return the address size given in the compilation unit header for CU.  */

CORE_ADDR
dwarf2_per_cu_addr_size (struct dwarf2_per_cu_data *per_cu)
{
  if (per_cu->cu)
    return per_cu->cu->header.addr_size;
  else
    {
      /* If the CU is not currently read in, we re-read its header.  */
      struct objfile *objfile = per_cu->objfile;
      struct dwarf2_per_objfile *per_objfile
        = objfile_data (objfile, dwarf2_objfile_data_key);
      gdb_byte *info_ptr = per_objfile->info.buffer + per_cu->offset;
      struct comp_unit_head cu_header;

      memset (&cu_header, 0, sizeof cu_header);
      read_comp_unit_head (&cu_header, info_ptr, objfile->obfd);
      return cu_header.addr_size;
    }
}

/* Return the offset size given in the compilation unit header for CU.  */

int
dwarf2_per_cu_offset_size (struct dwarf2_per_cu_data *per_cu)
{
  if (per_cu->cu)
    return per_cu->cu->header.offset_size;
  else
    {
      /* If the CU is not currently read in, we re-read its header.  */
      struct objfile *objfile = per_cu->objfile;
      struct dwarf2_per_objfile *per_objfile
        = objfile_data (objfile, dwarf2_objfile_data_key);
      gdb_byte *info_ptr = per_objfile->info.buffer + per_cu->offset;
      struct comp_unit_head cu_header;

      memset (&cu_header, 0, sizeof cu_header);
      read_comp_unit_head (&cu_header, info_ptr, objfile->obfd);
      return cu_header.offset_size;
    }
}

/* Return the text offset of the CU.  The returned offset comes from
   this CU's objfile.  If this objfile came from a separate debuginfo
   file, then the offset may be different from the corresponding
   offset in the parent objfile.  */

CORE_ADDR
dwarf2_per_cu_text_offset (struct dwarf2_per_cu_data *per_cu)
{
  struct objfile *objfile = per_cu->psymtab->objfile;

  return ANOFFSET (objfile->section_offsets, SECT_OFF_TEXT (objfile));
}

/* Locate the .debug_info compilation unit from CU's objfile which contains
   the DIE at OFFSET.  Raises an error on failure.  */

static struct dwarf2_per_cu_data *
dwarf2_find_containing_comp_unit (unsigned int offset,
                                  struct objfile *objfile)
{
  struct dwarf2_per_cu_data *this_cu;
  int low, high;

  low = 0;
  high = dwarf2_per_objfile->n_comp_units - 1;
  while (high > low)
    {
      int mid = low + (high - low) / 2;

      if (dwarf2_per_objfile->all_comp_units[mid]->offset >= offset)
        high = mid;
      else
        low = mid + 1;
    }
  gdb_assert (low == high);
  if (dwarf2_per_objfile->all_comp_units[low]->offset > offset)
    {
      if (low == 0)
        error (_("Dwarf Error: could not find partial DIE containing "
               "offset 0x%lx [in module %s]"),
               (long) offset, bfd_get_filename (objfile->obfd));

      gdb_assert (dwarf2_per_objfile->all_comp_units[low-1]->offset <= offset);
      return dwarf2_per_objfile->all_comp_units[low-1];
    }
  else
    {
      this_cu = dwarf2_per_objfile->all_comp_units[low];
      if (low == dwarf2_per_objfile->n_comp_units - 1
          && offset >= this_cu->offset + this_cu->length)
        error (_("invalid dwarf2 offset %u"), offset);
      gdb_assert (offset < this_cu->offset + this_cu->length);
      return this_cu;
    }
}

/* Locate the compilation unit from OBJFILE which is located at exactly
   OFFSET.  Raises an error on failure.  */

static struct dwarf2_per_cu_data *
dwarf2_find_comp_unit (unsigned int offset, struct objfile *objfile)
{
  struct dwarf2_per_cu_data *this_cu;

  this_cu = dwarf2_find_containing_comp_unit (offset, objfile);
  if (this_cu->offset != offset)
    error (_("no compilation unit with offset %u."), offset);
  return this_cu;
}

/* Malloc space for a dwarf2_cu for OBJFILE and initialize it.  */

static struct dwarf2_cu *
alloc_one_comp_unit (struct objfile *objfile)
{
  struct dwarf2_cu *cu = xcalloc (1, sizeof (struct dwarf2_cu));
  cu->objfile = objfile;
  obstack_init (&cu->comp_unit_obstack);
  return cu;
}

/* Release one cached compilation unit, CU.  We unlink it from the tree
   of compilation units, but we don't remove it from the read_in_chain;
   the caller is responsible for that.
   NOTE: DATA is a void * because this function is also used as a
   cleanup routine.  */

static void
free_one_comp_unit (void *data)
{
  struct dwarf2_cu *cu = data;

  if (cu->per_cu != NULL)
    cu->per_cu->cu = NULL;
  cu->per_cu = NULL;

  obstack_free (&cu->comp_unit_obstack, NULL);

  xfree (cu);
}

/* This cleanup function is passed the address of a dwarf2_cu on the stack
   when we're finished with it.  We can't free the pointer itself, but be
   sure to unlink it from the cache.  Also release any associated storage
   and perform cache maintenance.

   Only used during partial symbol parsing.  */

static void
free_stack_comp_unit (void *data)
{
  struct dwarf2_cu *cu = data;

  obstack_free (&cu->comp_unit_obstack, NULL);
  cu->partial_dies = NULL;

  if (cu->per_cu != NULL)
    {
      /* This compilation unit is on the stack in our caller, so we
         should not xfree it.  Just unlink it.  */
      cu->per_cu->cu = NULL;
      cu->per_cu = NULL;

      /* If we had a per-cu pointer, then we may have other compilation
         units loaded, so age them now.  */
      age_cached_comp_units ();
    }
}

/* Free all cached compilation units.  */

static void
free_cached_comp_units (void *data)
{
  struct dwarf2_per_cu_data *per_cu, **last_chain;

  per_cu = dwarf2_per_objfile->read_in_chain;
  last_chain = &dwarf2_per_objfile->read_in_chain;
  while (per_cu != NULL)
    {
      struct dwarf2_per_cu_data *next_cu;

      next_cu = per_cu->cu->read_in_chain;

      free_one_comp_unit (per_cu->cu);
      *last_chain = next_cu;

      per_cu = next_cu;
    }
}

/* Increase the age counter on each cached compilation unit, and free
   any that are too old.  */

static void
age_cached_comp_units (void)
{
  struct dwarf2_per_cu_data *per_cu, **last_chain;

  dwarf2_clear_marks (dwarf2_per_objfile->read_in_chain);
  per_cu = dwarf2_per_objfile->read_in_chain;
  while (per_cu != NULL)
    {
      per_cu->cu->last_used ++;
      if (per_cu->cu->last_used <= dwarf2_max_cache_age)
        dwarf2_mark (per_cu->cu);
      per_cu = per_cu->cu->read_in_chain;
    }

  per_cu = dwarf2_per_objfile->read_in_chain;
  last_chain = &dwarf2_per_objfile->read_in_chain;
  while (per_cu != NULL)
    {
      struct dwarf2_per_cu_data *next_cu;

      next_cu = per_cu->cu->read_in_chain;

      if (!per_cu->cu->mark)
        {
          free_one_comp_unit (per_cu->cu);
          *last_chain = next_cu;
        }
      else
        last_chain = &per_cu->cu->read_in_chain;

      per_cu = next_cu;
    }
}

/* Remove a single compilation unit from the cache.  */

static void
free_one_cached_comp_unit (void *target_cu)
{
  struct dwarf2_per_cu_data *per_cu, **last_chain;

  per_cu = dwarf2_per_objfile->read_in_chain;
  last_chain = &dwarf2_per_objfile->read_in_chain;
  while (per_cu != NULL)
    {
      struct dwarf2_per_cu_data *next_cu;

      next_cu = per_cu->cu->read_in_chain;

      if (per_cu->cu == target_cu)
        {
          free_one_comp_unit (per_cu->cu);
          *last_chain = next_cu;
          break;
        }
      else
        last_chain = &per_cu->cu->read_in_chain;

      per_cu = next_cu;
    }
}

/* Release all extra memory associated with OBJFILE.  */

void
dwarf2_free_objfile (struct objfile *objfile)
{
  dwarf2_per_objfile = objfile_data (objfile, dwarf2_objfile_data_key);

  if (dwarf2_per_objfile == NULL)
    return;

  /* Cached DIE trees use xmalloc and the comp_unit_obstack.  */
  free_cached_comp_units (NULL);

  if (dwarf2_per_objfile->using_index)
    {
      int i;

      for (i = 0; i < dwarf2_per_objfile->n_comp_units; ++i)
        {
          int j;
          struct dwarf2_per_cu_data *cu = dwarf2_per_objfile->all_comp_units[i];

          if (!cu->v.quick->lines)
            continue;

          for (j = 0; j < cu->v.quick->lines->num_file_names; ++j)
            {
              if (cu->v.quick->file_names)
                xfree ((void *) cu->v.quick->file_names[j]);
              if (cu->v.quick->full_names)
                xfree ((void *) cu->v.quick->full_names[j]);
            }

          free_line_header (cu->v.quick->lines);
        }
    }

  /* Everything else should be on the objfile obstack.  */
}

/* A pair of DIE offset and GDB type pointer.  We store these
   in a hash table separate from the DIEs, and preserve them
   when the DIEs are flushed out of cache.  */

struct dwarf2_offset_and_type
{
  unsigned int offset;
  struct type *type;
};

/* Hash function for a dwarf2_offset_and_type.  */

static hashval_t
offset_and_type_hash (const void *item)
{
  const struct dwarf2_offset_and_type *ofs = item;

  return ofs->offset;
}

/* Equality function for a dwarf2_offset_and_type.  */

static int
offset_and_type_eq (const void *item_lhs, const void *item_rhs)
{
  const struct dwarf2_offset_and_type *ofs_lhs = item_lhs;
  const struct dwarf2_offset_and_type *ofs_rhs = item_rhs;

  return ofs_lhs->offset == ofs_rhs->offset;
}

/* Set the type associated with DIE to TYPE.  Save it in CU's hash
   table if necessary.  For convenience, return TYPE.

   The DIEs reading must have careful ordering to:
    * Not cause infite loops trying to read in DIEs as a prerequisite for
      reading current DIE.
    * Not trying to dereference contents of still incompletely read in types
      while reading in other DIEs.
    * Enable referencing still incompletely read in types just by a pointer to
      the type without accessing its fields.

   Therefore caller should follow these rules:
     * Try to fetch any prerequisite types we may need to build this DIE type
       before building the type and calling set_die_type.
     * After building typer call set_die_type for current DIE as soon as
       possible before fetching more types to complete the current type.
     * Make the type as complete as possible before fetching more types.  */

static struct type *
set_die_type (struct die_info *die, struct type *type, struct dwarf2_cu *cu)
{
  struct dwarf2_offset_and_type **slot, ofs;

  /* For Ada types, make sure that the gnat-specific data is always
     initialized (if not already set).  There are a few types where
     we should not be doing so, because the type-specific area is
     already used to hold some other piece of info (eg: TYPE_CODE_FLT
     where the type-specific area is used to store the floatformat).
     But this is not a problem, because the gnat-specific information
     is actually not needed for these types.  */
  if (need_gnat_info (cu)
      && TYPE_CODE (type) != TYPE_CODE_FUNC
      && TYPE_CODE (type) != TYPE_CODE_FLT
      && !HAVE_GNAT_AUX_INFO (type))
    INIT_GNAT_SPECIFIC (type);

  if (cu->type_hash == NULL)
    {
      gdb_assert (cu->per_cu != NULL);
      cu->per_cu->type_hash
        = htab_create_alloc_ex (cu->header.length / 24,
                                offset_and_type_hash,
                                offset_and_type_eq,
                                NULL,
                                &cu->objfile->objfile_obstack,
                                hashtab_obstack_allocate,
                                dummy_obstack_deallocate);
      cu->type_hash = cu->per_cu->type_hash;
    }

  ofs.offset = die->offset;
  ofs.type = type;
  slot = (struct dwarf2_offset_and_type **)
    htab_find_slot_with_hash (cu->type_hash, &ofs, ofs.offset, INSERT);
  if (*slot)
    complaint (&symfile_complaints,
               _("A problem internal to GDB: DIE 0x%x has type already set"),
               die->offset);
  *slot = obstack_alloc (&cu->objfile->objfile_obstack, sizeof (**slot));
  **slot = ofs;
  return type;
}

/* Find the type for DIE in CU's type_hash, or return NULL if DIE does
   not have a saved type.  */

static struct type *
get_die_type (struct die_info *die, struct dwarf2_cu *cu)
{
  struct dwarf2_offset_and_type *slot, ofs;
  htab_t type_hash = cu->type_hash;

  if (type_hash == NULL)
    return NULL;

  ofs.offset = die->offset;
  slot = htab_find_with_hash (type_hash, &ofs, ofs.offset);
  if (slot)
    return slot->type;
  else
    return NULL;
}

/* Add a dependence relationship from CU to REF_PER_CU.  */

static void
dwarf2_add_dependence (struct dwarf2_cu *cu,
                       struct dwarf2_per_cu_data *ref_per_cu)
{
  void **slot;

  if (cu->dependencies == NULL)
    cu->dependencies
      = htab_create_alloc_ex (5, htab_hash_pointer, htab_eq_pointer,
                              NULL, &cu->comp_unit_obstack,
                              hashtab_obstack_allocate,
                              dummy_obstack_deallocate);

  slot = htab_find_slot (cu->dependencies, ref_per_cu, INSERT);
  if (*slot == NULL)
    *slot = ref_per_cu;
}

/* Subroutine of dwarf2_mark to pass to htab_traverse.
   Set the mark field in every compilation unit in the
   cache that we must keep because we are keeping CU.  */

static int
dwarf2_mark_helper (void **slot, void *data)
{
  struct dwarf2_per_cu_data *per_cu;

  per_cu = (struct dwarf2_per_cu_data *) *slot;
  if (per_cu->cu->mark)
    return 1;
  per_cu->cu->mark = 1;

  if (per_cu->cu->dependencies != NULL)
    htab_traverse (per_cu->cu->dependencies, dwarf2_mark_helper, NULL);

  return 1;
}

/* Set the mark field in CU and in every other compilation unit in the
   cache that we must keep because we are keeping CU.  */

static void
dwarf2_mark (struct dwarf2_cu *cu)
{
  if (cu->mark)
    return;
  cu->mark = 1;
  if (cu->dependencies != NULL)
    htab_traverse (cu->dependencies, dwarf2_mark_helper, NULL);
}

static void
dwarf2_clear_marks (struct dwarf2_per_cu_data *per_cu)
{
  while (per_cu)
    {
      per_cu->cu->mark = 0;
      per_cu = per_cu->cu->read_in_chain;
    }
}

/* Trivial hash function for partial_die_info: the hash value of a DIE
   is its offset in .debug_info for this objfile.  */

static hashval_t
partial_die_hash (const void *item)
{
  const struct partial_die_info *part_die = item;

  return part_die->offset;
}

/* Trivial comparison function for partial_die_info structures: two DIEs
   are equal if they have the same offset.  */

static int
partial_die_eq (const void *item_lhs, const void *item_rhs)
{
  const struct partial_die_info *part_die_lhs = item_lhs;
  const struct partial_die_info *part_die_rhs = item_rhs;

  return part_die_lhs->offset == part_die_rhs->offset;
}

static struct cmd_list_element *set_dwarf2_cmdlist;
static struct cmd_list_element *show_dwarf2_cmdlist;

static void
set_dwarf2_cmd (char *args, int from_tty)
{
  help_list (set_dwarf2_cmdlist, "maintenance set dwarf2 ", -1, gdb_stdout);
}

static void
show_dwarf2_cmd (char *args, int from_tty)
{
  cmd_show_list (show_dwarf2_cmdlist, from_tty, "");
}

/* If section described by INFO was mmapped, munmap it now.  */

static void
munmap_section_buffer (struct dwarf2_section_info *info)
{
  if (info->was_mmapped)
    {
#ifdef HAVE_MMAP
      intptr_t begin = (intptr_t) info->buffer;
      intptr_t map_begin = begin & ~(pagesize - 1);
      size_t map_length = info->size + begin - map_begin;

      gdb_assert (munmap ((void *) map_begin, map_length) == 0);
#else
      /* Without HAVE_MMAP, we should never be here to begin with.  */
      gdb_assert (0);
#endif
    }
}

/* munmap debug sections for OBJFILE, if necessary.  */

static void
dwarf2_per_objfile_free (struct objfile *objfile, void *d)
{
  struct dwarf2_per_objfile *data = d;

  munmap_section_buffer (&data->info);
  munmap_section_buffer (&data->abbrev);
  munmap_section_buffer (&data->line);
  munmap_section_buffer (&data->str);
  munmap_section_buffer (&data->macinfo);
  munmap_section_buffer (&data->ranges);
  munmap_section_buffer (&data->loc);
  munmap_section_buffer (&data->frame);
  munmap_section_buffer (&data->eh_frame);
  munmap_section_buffer (&data->gdb_index);
}

\f

/* The contents of the hash table we create when building the string
   table.  */
struct strtab_entry
{
  offset_type offset;
  const char *str;
};

/* Hash function for a strtab_entry.  */
static hashval_t
hash_strtab_entry (const void *e)
{
  const struct strtab_entry *entry = e;
  return mapped_index_string_hash (entry->str);
}

/* Equality function for a strtab_entry.  */
static int
eq_strtab_entry (const void *a, const void *b)
{
  const struct strtab_entry *ea = a;
  const struct strtab_entry *eb = b;
  return !strcmp (ea->str, eb->str);
}

/* Create a strtab_entry hash table.  */
static htab_t
create_strtab (void)
{
  return htab_create_alloc (100, hash_strtab_entry, eq_strtab_entry,
                            xfree, xcalloc, xfree);
}

/* Add a string to the constant pool.  Return the string's offset in
   host order.  */
static offset_type
add_string (htab_t table, struct obstack *cpool, const char *str)
{
  void **slot;
  struct strtab_entry entry;
  struct strtab_entry *result;

  entry.str = str;
  slot = htab_find_slot (table, &entry, INSERT);
  if (*slot)
    result = *slot;
  else
    {
      result = XNEW (struct strtab_entry);
      result->offset = obstack_object_size (cpool);
      result->str = str;
      obstack_grow_str0 (cpool, str);
      *slot = result;
    }
  return result->offset;
}

/* An entry in the symbol table.  */
struct symtab_index_entry
{
  /* The name of the symbol.  */
  const char *name;
  /* The offset of the name in the constant pool.  */
  offset_type index_offset;
  /* A sorted vector of the indices of all the CUs that hold an object
     of this name.  */
  VEC (offset_type) *cu_indices;
};

/* The symbol table.  This is a power-of-2-sized hash table.  */
struct mapped_symtab
{
  offset_type n_elements;
  offset_type size;
  struct symtab_index_entry **data;
};

/* Hash function for a symtab_index_entry.  */
static hashval_t
hash_symtab_entry (const void *e)
{
  const struct symtab_index_entry *entry = e;
  return iterative_hash (VEC_address (offset_type, entry->cu_indices),
                         sizeof (offset_type) * VEC_length (offset_type,
                                                            entry->cu_indices),
                         0);
}

/* Equality function for a symtab_index_entry.  */
static int
eq_symtab_entry (const void *a, const void *b)
{
  const struct symtab_index_entry *ea = a;
  const struct symtab_index_entry *eb = b;
  int len = VEC_length (offset_type, ea->cu_indices);
  if (len != VEC_length (offset_type, eb->cu_indices))
    return 0;
  return !memcmp (VEC_address (offset_type, ea->cu_indices),
                  VEC_address (offset_type, eb->cu_indices),
                  sizeof (offset_type) * len);
}

/* Destroy a symtab_index_entry.  */
static void
delete_symtab_entry (void *p)
{
  struct symtab_index_entry *entry = p;
  VEC_free (offset_type, entry->cu_indices);
  xfree (entry);
}

/* Create a hash table holding symtab_index_entry objects.  */
static htab_t
create_index_table (void)
{
  return htab_create_alloc (100, hash_symtab_entry, eq_symtab_entry,
                            delete_symtab_entry, xcalloc, xfree);
}

/* Create a new mapped symtab object.  */
static struct mapped_symtab *
create_mapped_symtab (void)
{
  struct mapped_symtab *symtab = XNEW (struct mapped_symtab);
  symtab->n_elements = 0;
  symtab->size = 1024;
  symtab->data = XCNEWVEC (struct symtab_index_entry *, symtab->size);
  return symtab;
}

/* Destroy a mapped_symtab.  */
static void
cleanup_mapped_symtab (void *p)
{
  struct mapped_symtab *symtab = p;
  /* The contents of the array are freed when the other hash table is
     destroyed.  */
  xfree (symtab->data);
  xfree (symtab);
}

/* Find a slot in SYMTAB for the symbol NAME.  Returns a pointer to
   the slot.  */
static struct symtab_index_entry **
find_slot (struct mapped_symtab *symtab, const char *name)
{
  offset_type index, step, hash = mapped_index_string_hash (name);

  index = hash & (symtab->size - 1);
  step = ((hash * 17) & (symtab->size - 1)) | 1;

  for (;;)
    {
      if (!symtab->data[index] || !strcmp (name, symtab->data[index]->name))
        return &symtab->data[index];
      index = (index + step) & (symtab->size - 1);
    }
}

/* Expand SYMTAB's hash table.  */
static void
hash_expand (struct mapped_symtab *symtab)
{
  offset_type old_size = symtab->size;
  offset_type i;
  struct symtab_index_entry **old_entries = symtab->data;

  symtab->size *= 2;
  symtab->data = XCNEWVEC (struct symtab_index_entry *, symtab->size);

  for (i = 0; i < old_size; ++i)
    {
      if (old_entries[i])
        {
          struct symtab_index_entry **slot = find_slot (symtab,
                                                        old_entries[i]->name);
          *slot = old_entries[i];
        }
    }

  xfree (old_entries);
}

/* Add an entry to SYMTAB.  NAME is the name of the symbol.  CU_INDEX
   is the index of the CU in which the symbol appears.  */
static void
add_index_entry (struct mapped_symtab *symtab, const char *name,
                 offset_type cu_index)
{
  struct symtab_index_entry **slot;

  ++symtab->n_elements;
  if (4 * symtab->n_elements / 3 >= symtab->size)
    hash_expand (symtab);

  slot = find_slot (symtab, name);
  if (!*slot)
    {
      *slot = XNEW (struct symtab_index_entry);
      (*slot)->name = name;
      (*slot)->cu_indices = NULL;
    }
  /* Don't push an index twice.  Due to how we add entries we only
     have to check the last one.  */ 
  if (VEC_empty (offset_type, (*slot)->cu_indices)
      || VEC_length (offset_type, (*slot)->cu_indices) != cu_index)
    VEC_safe_push (offset_type, (*slot)->cu_indices, cu_index);
}

/* Add a vector of indices to the constant pool.  */
static offset_type
add_indices_to_cpool (htab_t index_table, struct obstack *cpool,
                      struct symtab_index_entry *entry)
{
  void **slot;

  slot = htab_find_slot (index_table, entry, INSERT);
  if (!*slot)
    {
      offset_type len = VEC_length (offset_type, entry->cu_indices);
      offset_type val = MAYBE_SWAP (len);
      offset_type iter;
      int i;

      *slot = entry;
      entry->index_offset = obstack_object_size (cpool);

      obstack_grow (cpool, &val, sizeof (val));
      for (i = 0;
           VEC_iterate (offset_type, entry->cu_indices, i, iter);
           ++i)
        {
          val = MAYBE_SWAP (iter);
          obstack_grow (cpool, &val, sizeof (val));
        }
    }
  else
    {
      struct symtab_index_entry *old_entry = *slot;
      entry->index_offset = old_entry->index_offset;
      entry = old_entry;
    }
  return entry->index_offset;
}

/* Write the mapped hash table SYMTAB to the obstack OUTPUT, with
   constant pool entries going into the obstack CPOOL.  */
static void
write_hash_table (struct mapped_symtab *symtab,
                  struct obstack *output, struct obstack *cpool)
{
  offset_type i;
  htab_t index_table;
  htab_t str_table;

  index_table = create_index_table ();
  str_table = create_strtab ();
  /* We add all the index vectors to the constant pool first, to
     ensure alignment is ok.  */
  for (i = 0; i < symtab->size; ++i)
    {
      if (symtab->data[i])
        add_indices_to_cpool (index_table, cpool, symtab->data[i]);
    }

  /* Now write out the hash table.  */
  for (i = 0; i < symtab->size; ++i)
    {
      offset_type str_off, vec_off;

      if (symtab->data[i])
        {
          str_off = add_string (str_table, cpool, symtab->data[i]->name);
          vec_off = symtab->data[i]->index_offset;
        }
      else
        {
          /* While 0 is a valid constant pool index, it is not valid
             to have 0 for both offsets.  */
          str_off = 0;
          vec_off = 0;
        }

      str_off = MAYBE_SWAP (str_off);
      vec_off = MAYBE_SWAP (vec_off);

      obstack_grow (output, &str_off, sizeof (str_off));
      obstack_grow (output, &vec_off, sizeof (vec_off));
    }

  htab_delete (str_table);
  htab_delete (index_table);
}

/* Write an address entry to ADDR_OBSTACK.  The addresses are taken
   from PST; CU_INDEX is the index of the CU in the vector of all
   CUs.  */
static void
add_address_entry (struct objfile *objfile,
                   struct obstack *addr_obstack, struct partial_symtab *pst,
                   unsigned int cu_index)
{
  offset_type offset;
  char addr[8];
  CORE_ADDR baseaddr;

  baseaddr = ANOFFSET (objfile->section_offsets, SECT_OFF_TEXT (objfile));

  store_unsigned_integer (addr, 8, BFD_ENDIAN_LITTLE, pst->textlow - baseaddr);
  obstack_grow (addr_obstack, addr, 8);
  store_unsigned_integer (addr, 8, BFD_ENDIAN_LITTLE, pst->texthigh - baseaddr);
  obstack_grow (addr_obstack, addr, 8);
  offset = MAYBE_SWAP (cu_index);
  obstack_grow (addr_obstack, &offset, sizeof (offset_type));
}

/* Add a list of partial symbols to SYMTAB.  */
static void
write_psymbols (struct mapped_symtab *symtab,
                struct partial_symbol **psymp,
                int count,
                offset_type cu_index)
{
  for (; count-- > 0; ++psymp)
    {
      if (SYMBOL_LANGUAGE (*psymp) == language_ada)
        error (_("Ada is not currently supported by the index"));
      add_index_entry (symtab, SYMBOL_NATURAL_NAME (*psymp), cu_index);
    }
}

/* Write the contents of an ("unfinished") obstack to FILE.  Throw an
   exception if there is an error.  */
static void
write_obstack (FILE *file, struct obstack *obstack)
{
  if (fwrite (obstack_base (obstack), 1, obstack_object_size (obstack),
              file)
      != obstack_object_size (obstack))
    error (_("couldn't data write to file"));
}

/* Unlink a file if the argument is not NULL.  */
static void
unlink_if_set (void *p)
{
  char **filename = p;
  if (*filename)
    unlink (*filename);
}

/* Create an index file for OBJFILE in the directory DIR.  */
static void
write_psymtabs_to_index (struct objfile *objfile, const char *dir)
{
  struct cleanup *cleanup;
  char *filename, *cleanup_filename;
  struct obstack contents, addr_obstack, constant_pool, symtab_obstack, cu_list;
  int i;
  FILE *out_file;
  struct mapped_symtab *symtab;
  offset_type val, size_of_contents, total_len;
  struct stat st;
  char buf[8];

  if (!objfile->psymtabs)
    return;
  if (dwarf2_per_objfile->using_index)
    error (_("Cannot use an index to create the index"));

  if (stat (objfile->name, &st) < 0)
    perror_with_name (_("Could not stat"));

  filename = concat (dir, SLASH_STRING, lbasename (objfile->name),
                     INDEX_SUFFIX, (char *) NULL);
  cleanup = make_cleanup (xfree, filename);

  out_file = fopen (filename, "wb");
  if (!out_file)
    error (_("Can't open `%s' for writing"), filename);

  cleanup_filename = filename;
  make_cleanup (unlink_if_set, &cleanup_filename);

  symtab = create_mapped_symtab ();
  make_cleanup (cleanup_mapped_symtab, symtab);

  obstack_init (&addr_obstack);
  make_cleanup_obstack_free (&addr_obstack);

  obstack_init (&cu_list);
  make_cleanup_obstack_free (&cu_list);

  for (i = 0; i < dwarf2_per_objfile->n_comp_units; ++i)
    {
      struct dwarf2_per_cu_data *cu = dwarf2_per_objfile->all_comp_units[i];
      struct partial_symtab *psymtab = cu->v.psymtab;
      gdb_byte val[8];

      write_psymbols (symtab,
                      objfile->global_psymbols.list + psymtab->globals_offset,
                      psymtab->n_global_syms, i);
      write_psymbols (symtab,
                      objfile->static_psymbols.list + psymtab->statics_offset,
                      psymtab->n_static_syms, i);

      add_address_entry (objfile, &addr_obstack, psymtab, i);

      store_unsigned_integer (val, 8, BFD_ENDIAN_LITTLE, cu->offset);
      obstack_grow (&cu_list, val, 8);
      store_unsigned_integer (val, 8, BFD_ENDIAN_LITTLE, cu->length);
      obstack_grow (&cu_list, val, 8);
    }

  obstack_init (&constant_pool);
  make_cleanup_obstack_free (&constant_pool);
  obstack_init (&symtab_obstack);
  make_cleanup_obstack_free (&symtab_obstack);
  write_hash_table (symtab, &symtab_obstack, &constant_pool);

  obstack_init (&contents);
  make_cleanup_obstack_free (&contents);
  size_of_contents = 5 * sizeof (offset_type);
  total_len = size_of_contents;

  /* The version number.  */
  val = MAYBE_SWAP (1);
  obstack_grow (&contents, &val, sizeof (val));

  /* The offset of the CU list from the start of the file.  */
  val = MAYBE_SWAP (total_len);
  obstack_grow (&contents, &val, sizeof (val));
  total_len += obstack_object_size (&cu_list);

  /* The offset of the address table from the start of the file.  */
  val = MAYBE_SWAP (total_len);
  obstack_grow (&contents, &val, sizeof (val));
  total_len += obstack_object_size (&addr_obstack);

  /* The offset of the symbol table from the start of the file.  */
  val = MAYBE_SWAP (total_len);
  obstack_grow (&contents, &val, sizeof (val));
  total_len += obstack_object_size (&symtab_obstack);

  /* The offset of the constant pool from the start of the file.  */
  val = MAYBE_SWAP (total_len);
  obstack_grow (&contents, &val, sizeof (val));
  total_len += obstack_object_size (&constant_pool);

  gdb_assert (obstack_object_size (&contents) == size_of_contents);

  write_obstack (out_file, &contents);
  write_obstack (out_file, &cu_list);
  write_obstack (out_file, &addr_obstack);
  write_obstack (out_file, &symtab_obstack);
  write_obstack (out_file, &constant_pool);

  fclose (out_file);

  /* We want to keep the file, so we set cleanup_filename to NULL
     here.  See unlink_if_set.  */
  cleanup_filename = NULL;

  do_cleanups (cleanup);
}

/* The mapped index file format is designed to be directly mmap()able
   on any architecture.  In most cases, a datum is represented using a
   little-endian 32-bit integer value, called an offset_type.  Big
   endian machines must byte-swap the values before using them.
   Exceptions to this rule are noted.  The data is laid out such that
   alignment is always respected.

   A mapped index consists of several sections.

   1. The file header.  This is a sequence of values, of offset_type
   unless otherwise noted:
   [0] The version number.  Currently 1.
   [1] The offset, from the start of the file, of the CU list.
   [2] The offset, from the start of the file, of the address section.
   [3] The offset, from the start of the file, of the symbol table.
   [4] The offset, from the start of the file, of the constant pool.

   2. The CU list.  This is a sequence of pairs of 64-bit
   little-endian values.  The first element in each pair is the offset
   of a CU in the .debug_info section.  The second element in each
   pair is the length of that CU.  References to a CU elsewhere in the
   map are done using a CU index, which is just the 0-based index into
   this table.

   3. The address section.  The address section consists of a sequence
   of address entries.  Each address entry has three elements.
   [0] The low address.  This is a 64-bit little-endian value.
   [1] The high address.  This is a 64-bit little-endian value.
   [2] The CU index.  This is an offset_type value.

   4. The symbol table.  This is a hash table.  The size of the hash
   table is always a power of 2.  The initial hash and the step are
   currently defined by the `find_slot' function.

   Each slot in the hash table consists of a pair of offset_type
   values.  The first value is the offset of the symbol's name in the
   constant pool.  The second value is the offset of the CU vector in
   the constant pool.

   If both values are 0, then this slot in the hash table is empty.
   This is ok because while 0 is a valid constant pool index, it
   cannot be a valid index for both a string and a CU vector.

   A string in the constant pool is stored as a \0-terminated string,
   as you'd expect.

   A CU vector in the constant pool is a sequence of offset_type
   values.  The first value is the number of CU indices in the vector.
   Each subsequent value is the index of a CU in the CU list.  This
   element in the hash table is used to indicate which CUs define the
   symbol.

   5. The constant pool.  This is simply a bunch of bytes.  It is
   organized so that alignment is correct: CU vectors are stored
   first, followed by strings.  */
static void
save_gdb_index_command (char *arg, int from_tty)
{
  struct objfile *objfile;

  if (!arg || !*arg)
    error (_("usage: maintenance save-gdb-index DIRECTORY"));

  ALL_OBJFILES (objfile)
  {
    struct stat st;

    /* If the objfile does not correspond to an actual file, skip it.  */
    if (stat (objfile->name, &st) < 0)
      continue;

    dwarf2_per_objfile = objfile_data (objfile, dwarf2_objfile_data_key);
    if (dwarf2_per_objfile)
      {
        volatile struct gdb_exception except;

        TRY_CATCH (except, RETURN_MASK_ERROR)
          {
            write_psymtabs_to_index (objfile, arg);
          }
        if (except.reason < 0)
          exception_fprintf (gdb_stderr, except,
                             _("Error while writing index for `%s': "),
                             objfile->name);
      }
  }
}

\f

int dwarf2_always_disassemble;

static void
show_dwarf2_always_disassemble (struct ui_file *file, int from_tty,
                                struct cmd_list_element *c, const char *value)
{
  fprintf_filtered (file, _("\
Whether to always disassemble DWARF expressions is %s.\n"),
                    value);
}

void _initialize_dwarf2_read (void);

void
_initialize_dwarf2_read (void)
{
  dwarf2_objfile_data_key
    = register_objfile_data_with_cleanup (NULL, dwarf2_per_objfile_free);

  add_prefix_cmd ("dwarf2", class_maintenance, set_dwarf2_cmd, _("\
Set DWARF 2 specific variables.\n\
Configure DWARF 2 variables such as the cache size"),
                  &set_dwarf2_cmdlist, "maintenance set dwarf2 ",
                  0/*allow-unknown*/, &maintenance_set_cmdlist);

  add_prefix_cmd ("dwarf2", class_maintenance, show_dwarf2_cmd, _("\
Show DWARF 2 specific variables\n\
Show DWARF 2 variables such as the cache size"),
                  &show_dwarf2_cmdlist, "maintenance show dwarf2 ",
                  0/*allow-unknown*/, &maintenance_show_cmdlist);

  add_setshow_zinteger_cmd ("max-cache-age", class_obscure,
                            &dwarf2_max_cache_age, _("\
Set the upper bound on the age of cached dwarf2 compilation units."), _("\
Show the upper bound on the age of cached dwarf2 compilation units."), _("\
A higher limit means that cached compilation units will be stored\n\
in memory longer, and more total memory will be used.  Zero disables\n\
caching, which can slow down startup."),
                            NULL,
                            show_dwarf2_max_cache_age,
                            &set_dwarf2_cmdlist,
                            &show_dwarf2_cmdlist);

  add_setshow_boolean_cmd ("always-disassemble", class_obscure,
                           &dwarf2_always_disassemble, _("\
Set whether `info address' always disassembles DWARF expressions."), _("\
Show whether `info address' always disassembles DWARF expressions."), _("\
When enabled, DWARF expressions are always printed in an assembly-like\n\
syntax.  When disabled, expressions will be printed in a more\n\
conversational style, when possible."),
                           NULL,
                           show_dwarf2_always_disassemble,
                           &set_dwarf2_cmdlist,
                           &show_dwarf2_cmdlist);

  add_setshow_zinteger_cmd ("dwarf2-die", no_class, &dwarf2_die_debug, _("\
Set debugging of the dwarf2 DIE reader."), _("\
Show debugging of the dwarf2 DIE reader."), _("\
When enabled (non-zero), DIEs are dumped after they are read in.\n\
The value is the maximum depth to print."),
                            NULL,
                            NULL,
                            &setdebuglist, &showdebuglist);

  add_cmd ("gdb-index", class_files, save_gdb_index_command,
           _("Save a .gdb-index file"),
           &save_cmdlist);
}