// object.cc -- support for an object file for linking in gold
-// Copyright 2006, 2007 Free Software Foundation, Inc.
+// Copyright 2006, 2007, 2008, 2009 Free Software Foundation, Inc.
// Written by Ian Lance Taylor <iant@google.com>.
// This file is part of gold.
#include <cerrno>
#include <cstring>
#include <cstdarg>
+#include "demangle.h"
+#include "libiberty.h"
+#include "gc.h"
#include "target-select.h"
+#include "dwarf_reader.h"
#include "layout.h"
#include "output.h"
#include "symtab.h"
+#include "cref.h"
+#include "reloc.h"
#include "object.h"
#include "dynobj.h"
+#include "plugin.h"
namespace gold
{
-// Class Object.
+// Class Xindex.
-// Set the target based on fields in the ELF file header.
+// Initialize the symtab_xindex_ array. Find the SHT_SYMTAB_SHNDX
+// section and read it in. SYMTAB_SHNDX is the index of the symbol
+// table we care about.
+template<int size, bool big_endian>
void
-Object::set_target(int machine, int size, bool big_endian, int osabi,
- int abiversion)
+Xindex::initialize_symtab_xindex(Object* object, unsigned int sym_tab_shndx)
{
- Target* target = select_target(machine, size, big_endian, osabi, abiversion);
- if (target == NULL)
+ if (!this->symtab_xindex_.empty())
+ return;
+
+ gold_assert(sym_tab_shndx != 0);
+
+ // Look through the sections in reverse order, on the theory that it
+ // is more likely to be near the end than the beginning.
+ unsigned int i = object->shnum();
+ while (i > 0)
{
- fprintf(stderr, _("%s: %s: unsupported ELF machine number %d\n"),
- program_name, this->name().c_str(), machine);
- gold_exit(false);
+ --i;
+ if (object->section_type(i) == elfcpp::SHT_SYMTAB_SHNDX
+ && this->adjust_shndx(object->section_link(i)) == sym_tab_shndx)
+ {
+ this->read_symtab_xindex<size, big_endian>(object, i, NULL);
+ return;
+ }
}
- this->target_ = target;
+
+ object->error(_("missing SHT_SYMTAB_SHNDX section"));
}
-// Report an error for the elfcpp::Elf_file interface.
+// Read in the symtab_xindex_ array, given the section index of the
+// SHT_SYMTAB_SHNDX section. If PSHDRS is not NULL, it points at the
+// section headers.
+template<int size, bool big_endian>
void
-Object::error(const char* format, ...)
+Xindex::read_symtab_xindex(Object* object, unsigned int xindex_shndx,
+ const unsigned char* pshdrs)
{
- va_list args;
+ section_size_type bytecount;
+ const unsigned char* contents;
+ if (pshdrs == NULL)
+ contents = object->section_contents(xindex_shndx, &bytecount, false);
+ else
+ {
+ const unsigned char* p = (pshdrs
+ + (xindex_shndx
+ * elfcpp::Elf_sizes<size>::shdr_size));
+ typename elfcpp::Shdr<size, big_endian> shdr(p);
+ bytecount = convert_to_section_size_type(shdr.get_sh_size());
+ contents = object->get_view(shdr.get_sh_offset(), bytecount, true, false);
+ }
+
+ gold_assert(this->symtab_xindex_.empty());
+ this->symtab_xindex_.reserve(bytecount / 4);
+ for (section_size_type i = 0; i < bytecount; i += 4)
+ {
+ unsigned int shndx = elfcpp::Swap<32, big_endian>::readval(contents + i);
+ // We preadjust the section indexes we save.
+ this->symtab_xindex_.push_back(this->adjust_shndx(shndx));
+ }
+}
+
+// Symbol symndx has a section of SHN_XINDEX; return the real section
+// index.
+
+unsigned int
+Xindex::sym_xindex_to_shndx(Object* object, unsigned int symndx)
+{
+ if (symndx >= this->symtab_xindex_.size())
+ {
+ object->error(_("symbol %u out of range for SHT_SYMTAB_SHNDX section"),
+ symndx);
+ return elfcpp::SHN_UNDEF;
+ }
+ unsigned int shndx = this->symtab_xindex_[symndx];
+ if (shndx < elfcpp::SHN_LORESERVE || shndx >= object->shnum())
+ {
+ object->error(_("extended index for symbol %u out of range: %u"),
+ symndx, shndx);
+ return elfcpp::SHN_UNDEF;
+ }
+ return shndx;
+}
+
+// Class Object.
+
+// Report an error for this object file. This is used by the
+// elfcpp::Elf_file interface, and also called by the Object code
+// itself.
- fprintf(stderr, "%s: %s: ", program_name, this->name().c_str());
+void
+Object::error(const char* format, ...) const
+{
+ va_list args;
va_start(args, format);
- vfprintf(stderr, format, args);
+ char* buf = NULL;
+ if (vasprintf(&buf, format, args) < 0)
+ gold_nomem();
va_end(args);
- putc('\n', stderr);
-
- gold_exit(false);
+ gold_error(_("%s: %s"), this->name().c_str(), buf);
+ free(buf);
}
// Return a view of the contents of a section.
const unsigned char*
-Object::section_contents(unsigned int shndx, off_t* plen, bool cache)
+Object::section_contents(unsigned int shndx, section_size_type* plen,
+ bool cache)
{
Location loc(this->do_section_contents(shndx));
- *plen = loc.data_size;
- return this->get_view(loc.file_offset, loc.data_size, cache);
+ *plen = convert_to_section_size_type(loc.data_size);
+ if (*plen == 0)
+ {
+ static const unsigned char empty[1] = { '\0' };
+ return empty;
+ }
+ return this->get_view(loc.file_offset, *plen, true, cache);
}
// Read the section data into SD. This is code common to Sized_relobj
// Read the section headers.
const off_t shoff = elf_file->shoff();
- const unsigned int shnum = this->shnum();
- sd->section_headers = this->get_lasting_view(shoff, shnum * shdr_size, true);
+ const unsigned int sec_shnum = this->shnum();
+ sd->section_headers = this->get_lasting_view(shoff, sec_shnum * shdr_size,
+ true, true);
// Read the section names.
const unsigned char* pshdrs = sd->section_headers->data();
typename elfcpp::Shdr<size, big_endian> shdrnames(pshdrnames);
if (shdrnames.get_sh_type() != elfcpp::SHT_STRTAB)
- {
- fprintf(stderr,
- _("%s: %s: section name section has wrong type: %u\n"),
- program_name, this->name().c_str(),
- static_cast<unsigned int>(shdrnames.get_sh_type()));
- gold_exit(false);
- }
+ this->error(_("section name section has wrong type: %u"),
+ static_cast<unsigned int>(shdrnames.get_sh_type()));
- sd->section_names_size = shdrnames.get_sh_size();
+ sd->section_names_size =
+ convert_to_section_size_type(shdrnames.get_sh_size());
sd->section_names = this->get_lasting_view(shdrnames.get_sh_offset(),
- sd->section_names_size, false);
+ sd->section_names_size, false,
+ false);
}
-// If NAME is the name of a special .gnu.warning section, arrange for
+// If SNAME is the name of a special .gnu.warning section, arrange for
// the warning to be issued. SHNDX is the section index. Return
// whether it is a warning section.
bool
-Object::handle_gnu_warning_section(const char* name, unsigned int shndx,
+Object::handle_gnu_warning_section(const char* sname, unsigned int shndx,
Symbol_table* symtab)
{
const char warn_prefix[] = ".gnu.warning.";
const int warn_prefix_len = sizeof warn_prefix - 1;
- if (strncmp(name, warn_prefix, warn_prefix_len) == 0)
+ if (strncmp(sname, warn_prefix, warn_prefix_len) == 0)
+ {
+ // Read the section contents to get the warning text. It would
+ // be nicer if we only did this if we have to actually issue a
+ // warning. Unfortunately, warnings are issued as we relocate
+ // sections. That means that we can not lock the object then,
+ // as we might try to issue the same warning multiple times
+ // simultaneously.
+ section_size_type len;
+ const unsigned char* contents = this->section_contents(shndx, &len,
+ false);
+ if (len == 0)
+ {
+ const char* warning = sname + warn_prefix_len;
+ contents = reinterpret_cast<const unsigned char*>(warning);
+ len = strlen(warning);
+ }
+ std::string warning(reinterpret_cast<const char*>(contents), len);
+ symtab->add_warning(sname + warn_prefix_len, this, warning);
+ return true;
+ }
+ return false;
+}
+
+// If SNAME is the name of the special section which indicates that
+// this object was compiled with -fstack-split, mark it accordingly.
+
+bool
+Object::handle_split_stack_section(const char* sname)
+{
+ if (strcmp(sname, ".note.GNU-split-stack") == 0)
+ {
+ this->uses_split_stack_ = true;
+ return true;
+ }
+ if (strcmp(sname, ".note.GNU-no-split-stack") == 0)
{
- symtab->add_warning(name + warn_prefix_len, this, shndx);
+ this->has_no_split_stack_ = true;
return true;
}
return false;
}
+// Class Relobj
+
+// To copy the symbols data read from the file to a local data structure.
+// This function is called from do_layout only while doing garbage
+// collection.
+
+void
+Relobj::copy_symbols_data(Symbols_data* gc_sd, Read_symbols_data* sd,
+ unsigned int section_header_size)
+{
+ gc_sd->section_headers_data =
+ new unsigned char[(section_header_size)];
+ memcpy(gc_sd->section_headers_data, sd->section_headers->data(),
+ section_header_size);
+ gc_sd->section_names_data =
+ new unsigned char[sd->section_names_size];
+ memcpy(gc_sd->section_names_data, sd->section_names->data(),
+ sd->section_names_size);
+ gc_sd->section_names_size = sd->section_names_size;
+ if (sd->symbols != NULL)
+ {
+ gc_sd->symbols_data =
+ new unsigned char[sd->symbols_size];
+ memcpy(gc_sd->symbols_data, sd->symbols->data(),
+ sd->symbols_size);
+ }
+ else
+ {
+ gc_sd->symbols_data = NULL;
+ }
+ gc_sd->symbols_size = sd->symbols_size;
+ gc_sd->external_symbols_offset = sd->external_symbols_offset;
+ if (sd->symbol_names != NULL)
+ {
+ gc_sd->symbol_names_data =
+ new unsigned char[sd->symbol_names_size];
+ memcpy(gc_sd->symbol_names_data, sd->symbol_names->data(),
+ sd->symbol_names_size);
+ }
+ else
+ {
+ gc_sd->symbol_names_data = NULL;
+ }
+ gc_sd->symbol_names_size = sd->symbol_names_size;
+}
+
+// This function determines if a particular section name must be included
+// in the link. This is used during garbage collection to determine the
+// roots of the worklist.
+
+bool
+Relobj::is_section_name_included(const char* sname)
+{
+ if (is_prefix_of(".ctors", sname)
+ || is_prefix_of(".dtors", sname)
+ || is_prefix_of(".note", sname)
+ || is_prefix_of(".init", sname)
+ || is_prefix_of(".fini", sname)
+ || is_prefix_of(".gcc_except_table", sname)
+ || is_prefix_of(".jcr", sname)
+ || is_prefix_of(".preinit_array", sname)
+ || (is_prefix_of(".text", sname)
+ && strstr(sname, "personality"))
+ || (is_prefix_of(".data", sname)
+ && strstr(sname, "personality"))
+ || (is_prefix_of(".gnu.linkonce.d", sname)
+ && strstr(sname, "personality")))
+ {
+ return true;
+ }
+ return false;
+}
+
// Class Sized_relobj.
template<int size, bool big_endian>
Sized_relobj<size, big_endian>::Sized_relobj(
- const std::string& name,
- Input_file* input_file,
- off_t offset,
+ const std::string& aname,
+ Input_file* ainput_file,
+ off_t aoffset,
const elfcpp::Ehdr<size, big_endian>& ehdr)
- : Relobj(name, input_file, offset),
+ : Relobj(aname, ainput_file, aoffset),
elf_file_(this, ehdr),
symtab_shndx_(-1U),
local_symbol_count_(0),
output_local_symbol_count_(0),
- symbols_(NULL),
+ output_local_dynsym_count_(0),
+ symbols_(),
+ defined_count_(0),
local_symbol_offset_(0),
- local_values_()
+ local_dynsym_offset_(0),
+ local_values_(),
+ local_got_offsets_(),
+ kept_comdat_sections_(),
+ has_eh_frame_(false),
+ discarded_eh_frame_shndx_(-1U)
{
}
}
// Set up an object file based on the file header. This sets up the
-// target and reads the section information.
+// section information.
template<int size, bool big_endian>
void
-Sized_relobj<size, big_endian>::setup(
- const elfcpp::Ehdr<size, big_endian>& ehdr)
+Sized_relobj<size, big_endian>::do_setup()
{
- this->set_target(ehdr.get_e_machine(), size, big_endian,
- ehdr.get_e_ident()[elfcpp::EI_OSABI],
- ehdr.get_e_ident()[elfcpp::EI_ABIVERSION]);
-
- const unsigned int shnum = this->elf_file_.shnum();
- this->set_shnum(shnum);
+ const unsigned int sec_shnum = this->elf_file_.shnum();
+ this->set_shnum(sec_shnum);
}
// Find the SHT_SYMTAB section, given the section headers. The ELF
void
Sized_relobj<size, big_endian>::find_symtab(const unsigned char* pshdrs)
{
- const unsigned int shnum = this->shnum();
+ const unsigned int sec_shnum = this->shnum();
this->symtab_shndx_ = 0;
- if (shnum > 0)
+ if (sec_shnum > 0)
{
// Look through the sections in reverse order, since gas tends
// to put the symbol table at the end.
- const unsigned char* p = pshdrs + shnum * This::shdr_size;
- unsigned int i = shnum;
+ const unsigned char* p = pshdrs + sec_shnum * This::shdr_size;
+ unsigned int i = sec_shnum;
+ unsigned int xindex_shndx = 0;
+ unsigned int xindex_link = 0;
while (i > 0)
{
--i;
if (shdr.get_sh_type() == elfcpp::SHT_SYMTAB)
{
this->symtab_shndx_ = i;
+ if (xindex_shndx > 0 && xindex_link == i)
+ {
+ Xindex* xindex =
+ new Xindex(this->elf_file_.large_shndx_offset());
+ xindex->read_symtab_xindex<size, big_endian>(this,
+ xindex_shndx,
+ pshdrs);
+ this->set_xindex(xindex);
+ }
break;
}
+
+ // Try to pick up the SHT_SYMTAB_SHNDX section, if there is
+ // one. This will work if it follows the SHT_SYMTAB
+ // section.
+ if (shdr.get_sh_type() == elfcpp::SHT_SYMTAB_SHNDX)
+ {
+ xindex_shndx = i;
+ xindex_link = this->adjust_shndx(shdr.get_sh_link());
+ }
+ }
+ }
+}
+
+// Return the Xindex structure to use for object with lots of
+// sections.
+
+template<int size, bool big_endian>
+Xindex*
+Sized_relobj<size, big_endian>::do_initialize_xindex()
+{
+ gold_assert(this->symtab_shndx_ != -1U);
+ Xindex* xindex = new Xindex(this->elf_file_.large_shndx_offset());
+ xindex->initialize_symtab_xindex<size, big_endian>(this, this->symtab_shndx_);
+ return xindex;
+}
+
+// Return whether SHDR has the right type and flags to be a GNU
+// .eh_frame section.
+
+template<int size, bool big_endian>
+bool
+Sized_relobj<size, big_endian>::check_eh_frame_flags(
+ const elfcpp::Shdr<size, big_endian>* shdr) const
+{
+ return (shdr->get_sh_type() == elfcpp::SHT_PROGBITS
+ && (shdr->get_sh_flags() & elfcpp::SHF_ALLOC) != 0);
+}
+
+// Return whether there is a GNU .eh_frame section, given the section
+// headers and the section names.
+
+template<int size, bool big_endian>
+bool
+Sized_relobj<size, big_endian>::find_eh_frame(
+ const unsigned char* pshdrs,
+ const char* names,
+ section_size_type names_size) const
+{
+ const unsigned int sec_shnum = this->shnum();
+ const unsigned char* p = pshdrs + This::shdr_size;
+ for (unsigned int i = 1; i < sec_shnum; ++i, p += This::shdr_size)
+ {
+ typename This::Shdr shdr(p);
+ if (this->check_eh_frame_flags(&shdr))
+ {
+ if (shdr.get_sh_name() >= names_size)
+ {
+ this->error(_("bad section name offset for section %u: %lu"),
+ i, static_cast<unsigned long>(shdr.get_sh_name()));
+ continue;
+ }
+
+ const char* aname = names + shdr.get_sh_name();
+ if (strcmp(aname, ".eh_frame") == 0)
+ return true;
}
}
+ return false;
}
// Read the sections and symbols from an object file.
this->find_symtab(pshdrs);
+ const unsigned char* namesu = sd->section_names->data();
+ const char* names = reinterpret_cast<const char*>(namesu);
+ if (memmem(names, sd->section_names_size, ".eh_frame", 10) != NULL)
+ {
+ if (this->find_eh_frame(pshdrs, names, sd->section_names_size))
+ this->has_eh_frame_ = true;
+ }
+
+ sd->symbols = NULL;
+ sd->symbols_size = 0;
+ sd->external_symbols_offset = 0;
+ sd->symbol_names = NULL;
+ sd->symbol_names_size = 0;
+
if (this->symtab_shndx_ == 0)
{
// No symbol table. Weird but legal.
- sd->symbols = NULL;
- sd->symbols_size = 0;
- sd->symbol_names = NULL;
- sd->symbol_names_size = 0;
return;
}
+ this->symtab_shndx_ * This::shdr_size);
gold_assert(symtabshdr.get_sh_type() == elfcpp::SHT_SYMTAB);
- // We only need the external symbols.
- const int sym_size = This::sym_size;
+ // If this object has a .eh_frame section, we need all the symbols.
+ // Otherwise we only need the external symbols. While it would be
+ // simpler to just always read all the symbols, I've seen object
+ // files with well over 2000 local symbols, which for a 64-bit
+ // object file format is over 5 pages that we don't need to read
+ // now.
+
+ const int symsize = This::sym_size;
const unsigned int loccount = symtabshdr.get_sh_info();
this->local_symbol_count_ = loccount;
- off_t locsize = loccount * sym_size;
- off_t extoff = symtabshdr.get_sh_offset() + locsize;
- off_t extsize = symtabshdr.get_sh_size() - locsize;
+ this->local_values_.resize(loccount);
+ section_offset_type locsize = loccount * symsize;
+ off_t dataoff = symtabshdr.get_sh_offset();
+ section_size_type datasize =
+ convert_to_section_size_type(symtabshdr.get_sh_size());
+ off_t extoff = dataoff + locsize;
+ section_size_type extsize = datasize - locsize;
+
+ off_t readoff = this->has_eh_frame_ ? dataoff : extoff;
+ section_size_type readsize = this->has_eh_frame_ ? datasize : extsize;
+
+ if (readsize == 0)
+ {
+ // No external symbols. Also weird but also legal.
+ return;
+ }
- // Read the symbol table.
- File_view* fvsymtab = this->get_lasting_view(extoff, extsize, false);
+ File_view* fvsymtab = this->get_lasting_view(readoff, readsize, true, false);
// Read the section header for the symbol names.
- unsigned int strtab_shndx = symtabshdr.get_sh_link();
+ unsigned int strtab_shndx = this->adjust_shndx(symtabshdr.get_sh_link());
if (strtab_shndx >= this->shnum())
{
- fprintf(stderr, _("%s: %s: invalid symbol table name index: %u\n"),
- program_name, this->name().c_str(), strtab_shndx);
- gold_exit(false);
+ this->error(_("invalid symbol table name index: %u"), strtab_shndx);
+ return;
}
typename This::Shdr strtabshdr(pshdrs + strtab_shndx * This::shdr_size);
if (strtabshdr.get_sh_type() != elfcpp::SHT_STRTAB)
{
- fprintf(stderr,
- _("%s: %s: symbol table name section has wrong type: %u\n"),
- program_name, this->name().c_str(),
- static_cast<unsigned int>(strtabshdr.get_sh_type()));
- gold_exit(false);
+ this->error(_("symbol table name section has wrong type: %u"),
+ static_cast<unsigned int>(strtabshdr.get_sh_type()));
+ return;
}
// Read the symbol names.
File_view* fvstrtab = this->get_lasting_view(strtabshdr.get_sh_offset(),
- strtabshdr.get_sh_size(), true);
+ strtabshdr.get_sh_size(),
+ false, true);
sd->symbols = fvsymtab;
- sd->symbols_size = extsize;
+ sd->symbols_size = readsize;
+ sd->external_symbols_offset = this->has_eh_frame_ ? locsize : 0;
sd->symbol_names = fvstrtab;
- sd->symbol_names_size = strtabshdr.get_sh_size();
+ sd->symbol_names_size =
+ convert_to_section_size_type(strtabshdr.get_sh_size());
+}
+
+// Return the section index of symbol SYM. Set *VALUE to its value in
+// the object file. Set *IS_ORDINARY if this is an ordinary section
+// index. not a special cod between SHN_LORESERVE and SHN_HIRESERVE.
+// Note that for a symbol which is not defined in this object file,
+// this will set *VALUE to 0 and return SHN_UNDEF; it will not return
+// the final value of the symbol in the link.
+
+template<int size, bool big_endian>
+unsigned int
+Sized_relobj<size, big_endian>::symbol_section_and_value(unsigned int sym,
+ Address* value,
+ bool* is_ordinary)
+{
+ section_size_type symbols_size;
+ const unsigned char* symbols = this->section_contents(this->symtab_shndx_,
+ &symbols_size,
+ false);
+
+ const size_t count = symbols_size / This::sym_size;
+ gold_assert(sym < count);
+
+ elfcpp::Sym<size, big_endian> elfsym(symbols + sym * This::sym_size);
+ *value = elfsym.get_st_value();
+
+ return this->adjust_sym_shndx(sym, elfsym.get_st_shndx(), is_ordinary);
}
// Return whether to include a section group in the link. LAYOUT is
template<int size, bool big_endian>
bool
Sized_relobj<size, big_endian>::include_section_group(
- Layout* layout,
+ Symbol_table* symtab,
+ Layout* alayout,
unsigned int index,
- const elfcpp::Shdr<size, big_endian>& shdr,
+ const char* aname,
+ const unsigned char* shdrs,
+ const char* section_names,
+ section_size_type section_names_size,
std::vector<bool>* omit)
{
// Read the section contents.
+ typename This::Shdr shdr(shdrs + index * This::shdr_size);
const unsigned char* pcon = this->get_view(shdr.get_sh_offset(),
- shdr.get_sh_size(), false);
+ shdr.get_sh_size(), true, false);
const elfcpp::Elf_Word* pword =
reinterpret_cast<const elfcpp::Elf_Word*>(pcon);
// groups. Other section groups are always included in the link
// just like ordinary sections.
elfcpp::Elf_Word flags = elfcpp::Swap<32, big_endian>::readval(pword);
- if ((flags & elfcpp::GRP_COMDAT) == 0)
- return true;
// Look up the group signature, which is the name of a symbol. This
// is a lot of effort to go to to read a string. Why didn't they
- // just use the name of the SHT_GROUP section as the group
- // signature?
+ // just have the group signature point into the string table, rather
+ // than indirect through a symbol?
// Get the appropriate symbol table header (this will normally be
// the single SHT_SYMTAB section, but in principle it need not be).
- const unsigned int link = shdr.get_sh_link();
+ const unsigned int link = this->adjust_shndx(shdr.get_sh_link());
typename This::Shdr symshdr(this, this->elf_file_.section_header(link));
// Read the symbol table entry.
- if (shdr.get_sh_info() >= symshdr.get_sh_size() / This::sym_size)
+ unsigned int symndx = shdr.get_sh_info();
+ if (symndx >= symshdr.get_sh_size() / This::sym_size)
{
- fprintf(stderr, _("%s: %s: section group %u info %u out of range\n"),
- program_name, this->name().c_str(), index, shdr.get_sh_info());
- gold_exit(false);
+ this->error(_("section group %u info %u out of range"),
+ index, symndx);
+ return false;
}
- off_t symoff = symshdr.get_sh_offset() + shdr.get_sh_info() * This::sym_size;
- const unsigned char* psym = this->get_view(symoff, This::sym_size, true);
+ off_t symoff = symshdr.get_sh_offset() + symndx * This::sym_size;
+ const unsigned char* psym = this->get_view(symoff, This::sym_size, true,
+ false);
elfcpp::Sym<size, big_endian> sym(psym);
// Read the symbol table names.
- off_t symnamelen;
+ section_size_type symnamelen;
const unsigned char* psymnamesu;
- psymnamesu = this->section_contents(symshdr.get_sh_link(), &symnamelen,
- true);
+ psymnamesu = this->section_contents(this->adjust_shndx(symshdr.get_sh_link()),
+ &symnamelen, true);
const char* psymnames = reinterpret_cast<const char*>(psymnamesu);
// Get the section group signature.
if (sym.get_st_name() >= symnamelen)
{
- fprintf(stderr, _("%s: %s: symbol %u name offset %u out of range\n"),
- program_name, this->name().c_str(), shdr.get_sh_info(),
- sym.get_st_name());
- gold_exit(false);
+ this->error(_("symbol %u name offset %u out of range"),
+ symndx, sym.get_st_name());
+ return false;
}
- const char* signature = psymnames + sym.get_st_name();
+ std::string signature(psymnames + sym.get_st_name());
// It seems that some versions of gas will create a section group
// associated with a section symbol, and then fail to give a name to
// the section symbol. In such a case, use the name of the section.
- // FIXME.
- std::string secname;
if (signature[0] == '\0' && sym.get_st_type() == elfcpp::STT_SECTION)
{
- secname = this->section_name(sym.get_st_shndx());
- signature = secname.c_str();
+ bool is_ordinary;
+ unsigned int sym_shndx = this->adjust_sym_shndx(symndx,
+ sym.get_st_shndx(),
+ &is_ordinary);
+ if (!is_ordinary || sym_shndx >= this->shnum())
+ {
+ this->error(_("symbol %u invalid section index %u"),
+ symndx, sym_shndx);
+ return false;
+ }
+ typename This::Shdr member_shdr(shdrs + sym_shndx * This::shdr_size);
+ if (member_shdr.get_sh_name() < section_names_size)
+ signature = section_names + member_shdr.get_sh_name();
}
- // Record this section group, and see whether we've already seen one
- // with the same signature.
- if (layout->add_comdat(signature, true))
- return true;
+ // Record this section group in the layout, and see whether we've already
+ // seen one with the same signature.
+ bool include_group;
+ bool is_comdat;
+ Kept_section* kept_section = NULL;
+
+ if ((flags & elfcpp::GRP_COMDAT) == 0)
+ {
+ include_group = true;
+ is_comdat = false;
+ }
+ else
+ {
+ include_group = alayout->find_or_add_kept_section(signature,
+ this, index, true,
+ true, &kept_section);
+ is_comdat = true;
+ }
- // This is a duplicate. We want to discard the sections in this
- // group.
size_t count = shdr.get_sh_size() / sizeof(elfcpp::Elf_Word);
+
+ std::vector<unsigned int> shndxes;
+ bool relocate_group = include_group && parameters->options().relocatable();
+ if (relocate_group)
+ shndxes.reserve(count - 1);
+
for (size_t i = 1; i < count; ++i)
{
- elfcpp::Elf_Word secnum =
- elfcpp::Swap<32, big_endian>::readval(pword + i);
- if (secnum >= this->shnum())
+ elfcpp::Elf_Word shndx =
+ this->adjust_shndx(elfcpp::Swap<32, big_endian>::readval(pword + i));
+
+ if (relocate_group)
+ shndxes.push_back(shndx);
+
+ if (shndx >= this->shnum())
+ {
+ this->error(_("section %u in section group %u out of range"),
+ shndx, index);
+ continue;
+ }
+
+ // Check for an earlier section number, since we're going to get
+ // it wrong--we may have already decided to include the section.
+ if (shndx < index)
+ this->error(_("invalid section group %u refers to earlier section %u"),
+ index, shndx);
+
+ // Get the name of the member section.
+ typename This::Shdr member_shdr(shdrs + shndx * This::shdr_size);
+ if (member_shdr.get_sh_name() >= section_names_size)
+ {
+ // This is an error, but it will be diagnosed eventually
+ // in do_layout, so we don't need to do anything here but
+ // ignore it.
+ continue;
+ }
+ std::string mname(section_names + member_shdr.get_sh_name());
+
+ if (include_group)
{
- fprintf(stderr,
- _("%s: %s: section %u in section group %u out of range"),
- program_name, this->name().c_str(), secnum,
- index);
- gold_exit(false);
+ if (is_comdat)
+ kept_section->add_comdat_section(mname, shndx,
+ member_shdr.get_sh_size());
}
- (*omit)[secnum] = true;
+ else
+ {
+ (*omit)[shndx] = true;
+
+ if (is_comdat)
+ {
+ Relobj* kept_object = kept_section->object();
+ if (kept_section->is_comdat())
+ {
+ // Find the corresponding kept section, and store
+ // that info in the discarded section table.
+ unsigned int kept_shndx;
+ uint64_t kept_size;
+ if (kept_section->find_comdat_section(mname, &kept_shndx,
+ &kept_size))
+ {
+ // We don't keep a mapping for this section if
+ // it has a different size. The mapping is only
+ // used for relocation processing, and we don't
+ // want to treat the sections as similar if the
+ // sizes are different. Checking the section
+ // size is the approach used by the GNU linker.
+ if (kept_size == member_shdr.get_sh_size())
+ this->set_kept_comdat_section(shndx, kept_object,
+ kept_shndx);
+ }
+ }
+ else
+ {
+ // The existing section is a linkonce section. Add
+ // a mapping if there is exactly one section in the
+ // group (which is true when COUNT == 2) and if it
+ // is the same size.
+ if (count == 2
+ && (kept_section->linkonce_size()
+ == member_shdr.get_sh_size()))
+ this->set_kept_comdat_section(shndx, kept_object,
+ kept_section->shndx());
+ }
+ }
+ }
}
- return false;
+ if (relocate_group)
+ alayout->layout_group(symtab, this, index, aname, signature.c_str(),
+ shdr, flags, &shndxes);
+
+ return include_group;
}
// Whether to include a linkonce section in the link. NAME is the
template<int size, bool big_endian>
bool
Sized_relobj<size, big_endian>::include_linkonce_section(
- Layout* layout,
- const char* name,
- const elfcpp::Shdr<size, big_endian>&)
+ Layout* alayout,
+ unsigned int index,
+ const char* aname,
+ const elfcpp::Shdr<size, big_endian>& shdr)
{
- const char* symname = strrchr(name, '.') + 1;
- bool include1 = layout->add_comdat(symname, false);
- bool include2 = layout->add_comdat(name, true);
+ typename elfcpp::Elf_types<size>::Elf_WXword sh_size = shdr.get_sh_size();
+ // In general the symbol name we want will be the string following
+ // the last '.'. However, we have to handle the case of
+ // .gnu.linkonce.t.__i686.get_pc_thunk.bx, which was generated by
+ // some versions of gcc. So we use a heuristic: if the name starts
+ // with ".gnu.linkonce.t.", we use everything after that. Otherwise
+ // we look for the last '.'. We can't always simply skip
+ // ".gnu.linkonce.X", because we have to deal with cases like
+ // ".gnu.linkonce.d.rel.ro.local".
+ const char* const linkonce_t = ".gnu.linkonce.t.";
+ const char* symname;
+ if (strncmp(aname, linkonce_t, strlen(linkonce_t)) == 0)
+ symname = aname + strlen(linkonce_t);
+ else
+ symname = strrchr(aname, '.') + 1;
+ std::string sig1(symname);
+ std::string sig2(aname);
+ Kept_section* kept1;
+ Kept_section* kept2;
+ bool include1 = alayout->find_or_add_kept_section(sig1, this, index, false,
+ false, &kept1);
+ bool include2 = alayout->find_or_add_kept_section(sig2, this, index, false,
+ true, &kept2);
+
+ if (!include2)
+ {
+ // We are not including this section because we already saw the
+ // name of the section as a signature. This normally implies
+ // that the kept section is another linkonce section. If it is
+ // the same size, record it as the section which corresponds to
+ // this one.
+ if (kept2->object() != NULL
+ && !kept2->is_comdat()
+ && kept2->linkonce_size() == sh_size)
+ this->set_kept_comdat_section(index, kept2->object(), kept2->shndx());
+ }
+ else if (!include1)
+ {
+ // The section is being discarded on the basis of its symbol
+ // name. This means that the corresponding kept section was
+ // part of a comdat group, and it will be difficult to identify
+ // the specific section within that group that corresponds to
+ // this linkonce section. We'll handle the simple case where
+ // the group has only one member section. Otherwise, it's not
+ // worth the effort.
+ unsigned int kept_shndx;
+ uint64_t kept_size;
+ if (kept1->object() != NULL
+ && kept1->is_comdat()
+ && kept1->find_single_comdat_section(&kept_shndx, &kept_size)
+ && kept_size == sh_size)
+ this->set_kept_comdat_section(index, kept1->object(), kept_shndx);
+ }
+ else
+ {
+ kept1->set_linkonce_size(sh_size);
+ kept2->set_linkonce_size(sh_size);
+ }
+
return include1 && include2;
}
+// Layout an input section.
+
+template<int size, bool big_endian>
+inline void
+Sized_relobj<size, big_endian>::layout_section(Layout* alayout,
+ unsigned int shndx,
+ const char* aname,
+ typename This::Shdr& shdr,
+ unsigned int reloc_shndx,
+ unsigned int reloc_type)
+{
+ off_t aoffset;
+ Output_section* os = alayout->layout(this, shndx, aname, shdr,
+ reloc_shndx, reloc_type, &aoffset);
+
+ this->output_sections()[shndx] = os;
+ if (aoffset == -1)
+ this->section_offsets_[shndx] = invalid_address;
+ else
+ this->section_offsets_[shndx] = convert_types<Address, off_t>(aoffset);
+
+ // If this section requires special handling, and if there are
+ // relocs that apply to it, then we must do the special handling
+ // before we apply the relocs.
+ if (aoffset == -1 && reloc_shndx != 0)
+ this->set_relocs_must_follow_section_writes();
+}
+
// Lay out the input sections. We walk through the sections and check
// whether they should be included in the link. If they should, we
// pass them to the Layout object, which will return an output section
-// and an offset.
+// and an offset.
+// During garbage collection (--gc-sections) and identical code folding
+// (--icf), this function is called twice. When it is called the first
+// time, it is for setting up some sections as roots to a work-list for
+// --gc-sections and to do comdat processing. Actual layout happens the
+// second time around after all the relevant sections have been determined.
+// The first time, is_worklist_ready or is_icf_ready is false. It is then
+// set to true after the garbage collection worklist or identical code
+// folding is processed and the relevant sections to be kept are
+// determined. Then, this function is called again to layout the sections.
template<int size, bool big_endian>
void
Sized_relobj<size, big_endian>::do_layout(Symbol_table* symtab,
- Layout* layout,
+ Layout* alayout,
Read_symbols_data* sd)
{
- const unsigned int shnum = this->shnum();
- if (shnum == 0)
+ const unsigned int sec_shnum = this->shnum();
+ bool is_gc_pass_one = ((parameters->options().gc_sections()
+ && !symtab->gc()->is_worklist_ready())
+ || (parameters->options().icf_enabled()
+ && !symtab->icf()->is_icf_ready()));
+
+ bool is_gc_pass_two = ((parameters->options().gc_sections()
+ && symtab->gc()->is_worklist_ready())
+ || (parameters->options().icf_enabled()
+ && symtab->icf()->is_icf_ready()));
+
+ bool is_gc_or_icf = (parameters->options().gc_sections()
+ || parameters->options().icf_enabled());
+
+ // Both is_gc_pass_one and is_gc_pass_two should not be true.
+ gold_assert(!(is_gc_pass_one && is_gc_pass_two));
+
+ if (sec_shnum == 0)
return;
+ Symbols_data* gc_sd = NULL;
+ if (is_gc_pass_one)
+ {
+ // During garbage collection save the symbols data to use it when
+ // re-entering this function.
+ gc_sd = new Symbols_data;
+ this->copy_symbols_data(gc_sd, sd, This::shdr_size * sec_shnum);
+ this->set_symbols_data(gc_sd);
+ }
+ else if (is_gc_pass_two)
+ {
+ gc_sd = this->get_symbols_data();
+ }
+
+ const unsigned char* section_headers_data = NULL;
+ section_size_type section_names_size;
+ const unsigned char* symbols_data = NULL;
+ section_size_type symbols_size;
+ section_offset_type external_symbols_offset;
+ const unsigned char* symbol_names_data = NULL;
+ section_size_type symbol_names_size;
+
+ if (is_gc_or_icf)
+ {
+ section_headers_data = gc_sd->section_headers_data;
+ section_names_size = gc_sd->section_names_size;
+ symbols_data = gc_sd->symbols_data;
+ symbols_size = gc_sd->symbols_size;
+ external_symbols_offset = gc_sd->external_symbols_offset;
+ symbol_names_data = gc_sd->symbol_names_data;
+ symbol_names_size = gc_sd->symbol_names_size;
+ }
+ else
+ {
+ section_headers_data = sd->section_headers->data();
+ section_names_size = sd->section_names_size;
+ if (sd->symbols != NULL)
+ symbols_data = sd->symbols->data();
+ symbols_size = sd->symbols_size;
+ external_symbols_offset = sd->external_symbols_offset;
+ if (sd->symbol_names != NULL)
+ symbol_names_data = sd->symbol_names->data();
+ symbol_names_size = sd->symbol_names_size;
+ }
// Get the section headers.
- const unsigned char* pshdrs = sd->section_headers->data();
+ const unsigned char* shdrs = section_headers_data;
+ const unsigned char* pshdrs;
// Get the section names.
- const unsigned char* pnamesu = sd->section_names->data();
- const char* pnames = reinterpret_cast<const char*>(pnamesu);
-
- std::vector<Map_to_output>& map_sections(this->map_to_output());
- map_sections.resize(shnum);
+ const unsigned char* pnamesu = (is_gc_or_icf)
+ ? gc_sd->section_names_data
+ : sd->section_names->data();
- // Keep track of which sections to omit.
- std::vector<bool> omit(shnum, false);
+ const char* pnames = reinterpret_cast<const char*>(pnamesu);
+ // If any input files have been claimed by plugins, we need to defer
+ // actual layout until the replacement files have arrived.
+ const bool should_defer_layout =
+ (parameters->options().has_plugins()
+ && parameters->options().plugins()->should_defer_layout());
+ unsigned int num_sections_to_defer = 0;
+
+ // For each section, record the index of the reloc section if any.
+ // Use 0 to mean that there is no reloc section, -1U to mean that
+ // there is more than one.
+ std::vector<unsigned int> reloc_shndx(sec_shnum, 0);
+ std::vector<unsigned int> reloc_type(sec_shnum, elfcpp::SHT_NULL);
// Skip the first, dummy, section.
- pshdrs += This::shdr_size;
- for (unsigned int i = 1; i < shnum; ++i, pshdrs += This::shdr_size)
+ pshdrs = shdrs + This::shdr_size;
+ for (unsigned int i = 1; i < sec_shnum; ++i, pshdrs += This::shdr_size)
{
typename This::Shdr shdr(pshdrs);
- if (shdr.get_sh_name() >= sd->section_names_size)
- {
- fprintf(stderr,
- _("%s: %s: bad section name offset for section %u: %lu\n"),
- program_name, this->name().c_str(), i,
- static_cast<unsigned long>(shdr.get_sh_name()));
- gold_exit(false);
- }
-
- const char* name = pnames + shdr.get_sh_name();
-
- if (this->handle_gnu_warning_section(name, i, symtab))
- {
- if (!parameters->output_is_object())
- omit[i] = true;
- }
+ // Count the number of sections whose layout will be deferred.
+ if (should_defer_layout && (shdr.get_sh_flags() & elfcpp::SHF_ALLOC))
+ ++num_sections_to_defer;
- bool discard = omit[i];
- if (!discard)
+ unsigned int sh_type = shdr.get_sh_type();
+ if (sh_type == elfcpp::SHT_REL || sh_type == elfcpp::SHT_RELA)
{
- if (shdr.get_sh_type() == elfcpp::SHT_GROUP)
+ unsigned int target_shndx = this->adjust_shndx(shdr.get_sh_info());
+ if (target_shndx == 0 || target_shndx >= sec_shnum)
{
- if (!this->include_section_group(layout, i, shdr, &omit))
- discard = true;
+ this->error(_("relocation section %u has bad info %u"),
+ i, target_shndx);
+ continue;
}
- else if ((shdr.get_sh_flags() & elfcpp::SHF_GROUP) == 0
- && Layout::is_linkonce(name))
+
+ if (reloc_shndx[target_shndx] != 0)
+ reloc_shndx[target_shndx] = -1U;
+ else
{
- if (!this->include_linkonce_section(layout, name, shdr))
- discard = true;
+ reloc_shndx[target_shndx] = i;
+ reloc_type[target_shndx] = sh_type;
}
}
-
- if (discard)
- {
- // Do not include this section in the link.
- map_sections[i].output_section = NULL;
- continue;
- }
-
- off_t offset;
- Output_section* os = layout->layout(this, i, name, shdr, &offset);
-
- map_sections[i].output_section = os;
- map_sections[i].offset = offset;
}
- delete sd->section_headers;
- sd->section_headers = NULL;
- delete sd->section_names;
- sd->section_names = NULL;
-}
+ Output_sections& out_sections(this->output_sections());
+ std::vector<Address>& out_section_offsets(this->section_offsets_);
-// Add the symbols to the symbol table.
+ if (!is_gc_pass_two)
+ {
+ out_sections.resize(sec_shnum);
+ out_section_offsets.resize(sec_shnum);
+ }
-template<int size, bool big_endian>
-void
-Sized_relobj<size, big_endian>::do_add_symbols(Symbol_table* symtab,
- Read_symbols_data* sd)
-{
- if (sd->symbols == NULL)
+ // If we are only linking for symbols, then there is nothing else to
+ // do here.
+ if (this->input_file()->just_symbols())
{
- gold_assert(sd->symbol_names == NULL);
+ if (!is_gc_pass_two)
+ {
+ delete sd->section_headers;
+ sd->section_headers = NULL;
+ delete sd->section_names;
+ sd->section_names = NULL;
+ }
return;
}
- const int sym_size = This::sym_size;
- size_t symcount = sd->symbols_size / sym_size;
- if (symcount * sym_size != sd->symbols_size)
+ if (num_sections_to_defer > 0)
{
- fprintf(stderr,
- _("%s: %s: size of symbols is not multiple of symbol size\n"),
- program_name, this->name().c_str());
- gold_exit(false);
+ parameters->options().plugins()->add_deferred_layout_object(this);
+ this->deferred_layout_.reserve(num_sections_to_defer);
}
- this->symbols_ = new Symbol*[symcount];
+ // Whether we've seen a .note.GNU-stack section.
+ bool seen_gnu_stack = false;
+ // The flags of a .note.GNU-stack section.
+ uint64_t gnu_stack_flags = 0;
- const char* sym_names =
- reinterpret_cast<const char*>(sd->symbol_names->data());
- symtab->add_from_relobj(this, sd->symbols->data(), symcount, sym_names,
- sd->symbol_names_size, this->symbols_);
+ // Keep track of which sections to omit.
+ std::vector<bool> omit(sec_shnum, false);
- delete sd->symbols;
- sd->symbols = NULL;
- delete sd->symbol_names;
- sd->symbol_names = NULL;
-}
+ // Keep track of reloc sections when emitting relocations.
+ const bool relocatable = parameters->options().relocatable();
+ const bool emit_rels = (relocatable
+ || parameters->options().emit_relocs());
+ std::vector<unsigned int> reloc_sections;
-// Finalize the local symbols. Here we record the file offset at
-// which they should be output, we add their names to *POOL, and we
-// add their values to THIS->LOCAL_VALUES_. Return the symbol index.
-// This function is always called from the main thread. The actual
-// output of the local symbols will occur in a separate task.
+ // Keep track of .eh_frame sections.
+ std::vector<unsigned int> eh_frame_sections;
-template<int size, bool big_endian>
-unsigned int
-Sized_relobj<size, big_endian>::do_finalize_local_symbols(unsigned int index,
- off_t off,
- Stringpool* pool)
-{
- gold_assert(this->symtab_shndx_ != -1U);
- if (this->symtab_shndx_ == 0)
+ // Skip the first, dummy, section.
+ pshdrs = shdrs + This::shdr_size;
+ for (unsigned int i = 1; i < sec_shnum; ++i, pshdrs += This::shdr_size)
{
- // This object has no symbols. Weird but legal.
- return index;
- }
+ typename This::Shdr shdr(pshdrs);
- gold_assert(off == static_cast<off_t>(align_address(off, size >> 3)));
+ if (shdr.get_sh_name() >= section_names_size)
+ {
+ this->error(_("bad section name offset for section %u: %lu"),
+ i, static_cast<unsigned long>(shdr.get_sh_name()));
+ return;
+ }
- this->local_symbol_offset_ = off;
+ const char* sname = pnames + shdr.get_sh_name();
- // Read the symbol table section header.
- const unsigned int symtab_shndx = this->symtab_shndx_;
- typename This::Shdr symtabshdr(this,
- this->elf_file_.section_header(symtab_shndx));
- gold_assert(symtabshdr.get_sh_type() == elfcpp::SHT_SYMTAB);
+ if (!is_gc_pass_two)
+ {
+ if (this->handle_gnu_warning_section(sname, i, symtab))
+ {
+ if (!relocatable)
+ omit[i] = true;
+ }
- // Read the local symbols.
- const int sym_size = This::sym_size;
- const unsigned int loccount = this->local_symbol_count_;
- gold_assert(loccount == symtabshdr.get_sh_info());
- off_t locsize = loccount * sym_size;
- const unsigned char* psyms = this->get_view(symtabshdr.get_sh_offset(),
- locsize, true);
+ // The .note.GNU-stack section is special. It gives the
+ // protection flags that this object file requires for the stack
+ // in memory.
+ if (strcmp(sname, ".note.GNU-stack") == 0)
+ {
+ seen_gnu_stack = true;
+ gnu_stack_flags |= shdr.get_sh_flags();
+ omit[i] = true;
+ }
+
+ // The .note.GNU-split-stack section is also special. It
+ // indicates that the object was compiled with
+ // -fsplit-stack.
+ if (this->handle_split_stack_section(sname))
+ {
+ if (!parameters->options().relocatable()
+ && !parameters->options().shared())
+ omit[i] = true;
+ }
- this->local_values_.resize(loccount);
+ // Skip attributes section.
+ if (parameters->target().is_attributes_section(sname))
+ {
+ omit[i] = true;
+ }
- // Read the symbol names.
- const unsigned int strtab_shndx = symtabshdr.get_sh_link();
- off_t strtab_size;
- const unsigned char* pnamesu = this->section_contents(strtab_shndx,
- &strtab_size,
- true);
- const char* pnames = reinterpret_cast<const char*>(pnamesu);
+ bool discard = omit[i];
+ if (!discard)
+ {
+ if (shdr.get_sh_type() == elfcpp::SHT_GROUP)
+ {
+ if (!this->include_section_group(symtab, alayout, i, sname,
+ shdrs, pnames,
+ section_names_size,
+ &omit))
+ discard = true;
+ }
+ else if ((shdr.get_sh_flags() & elfcpp::SHF_GROUP) == 0
+ && Layout::is_linkonce(sname))
+ {
+ if (!this->include_linkonce_section(alayout, i, sname, shdr))
+ discard = true;
+ }
+ }
+
+ if (discard)
+ {
+ // Do not include this section in the link.
+ out_sections[i] = NULL;
+ out_section_offsets[i] = invalid_address;
+ continue;
+ }
+ }
+
+ if (is_gc_pass_one && parameters->options().gc_sections())
+ {
+ if (is_section_name_included(sname)
+ || shdr.get_sh_type() == elfcpp::SHT_INIT_ARRAY
+ || shdr.get_sh_type() == elfcpp::SHT_FINI_ARRAY)
+ {
+ symtab->gc()->worklist().push(Section_id(this, i));
+ }
+ }
+
+ // When doing a relocatable link we are going to copy input
+ // reloc sections into the output. We only want to copy the
+ // ones associated with sections which are not being discarded.
+ // However, we don't know that yet for all sections. So save
+ // reloc sections and process them later. Garbage collection is
+ // not triggered when relocatable code is desired.
+ if (emit_rels
+ && (shdr.get_sh_type() == elfcpp::SHT_REL
+ || shdr.get_sh_type() == elfcpp::SHT_RELA))
+ {
+ reloc_sections.push_back(i);
+ continue;
+ }
+
+ if (relocatable && shdr.get_sh_type() == elfcpp::SHT_GROUP)
+ continue;
+
+ // The .eh_frame section is special. It holds exception frame
+ // information that we need to read in order to generate the
+ // exception frame header. We process these after all the other
+ // sections so that the exception frame reader can reliably
+ // determine which sections are being discarded, and discard the
+ // corresponding information.
+ if (!relocatable
+ && strcmp(sname, ".eh_frame") == 0
+ && this->check_eh_frame_flags(&shdr))
+ {
+ if (is_gc_pass_one)
+ {
+ out_sections[i] = reinterpret_cast<Output_section*>(1);
+ out_section_offsets[i] = invalid_address;
+ }
+ else
+ eh_frame_sections.push_back(i);
+ continue;
+ }
+
+ if (is_gc_pass_two && parameters->options().gc_sections())
+ {
+ // This is executed during the second pass of garbage
+ // collection. do_layout has been called before and some
+ // sections have been already discarded. Simply ignore
+ // such sections this time around.
+ if (out_sections[i] == NULL)
+ {
+ gold_assert(out_section_offsets[i] == invalid_address);
+ continue;
+ }
+ if (((shdr.get_sh_flags() & elfcpp::SHF_ALLOC) != 0)
+ && symtab->gc()->is_section_garbage(this, i))
+ {
+ if (parameters->options().print_gc_sections())
+ gold_info(_("%s: removing unused section from '%s'"
+ " in file '%s'"),
+ program_name, this->section_name(i).c_str(),
+ this->name().c_str());
+ out_sections[i] = NULL;
+ out_section_offsets[i] = invalid_address;
+ continue;
+ }
+ }
+
+ if (is_gc_pass_two && parameters->options().icf_enabled())
+ {
+ if (out_sections[i] == NULL)
+ {
+ gold_assert(out_section_offsets[i] == invalid_address);
+ continue;
+ }
+ if (((shdr.get_sh_flags() & elfcpp::SHF_ALLOC) != 0)
+ && symtab->icf()->is_section_folded(this, i))
+ {
+ if (parameters->options().print_icf_sections())
+ {
+ Section_id folded =
+ symtab->icf()->get_folded_section(this, i);
+ Relobj* folded_obj =
+ reinterpret_cast<Relobj*>(folded.first);
+ gold_info(_("%s: ICF folding section '%s' in file '%s'"
+ "into '%s' in file '%s'"),
+ program_name, this->section_name(i).c_str(),
+ this->name().c_str(),
+ folded_obj->section_name(folded.second).c_str(),
+ folded_obj->name().c_str());
+ }
+ out_sections[i] = NULL;
+ out_section_offsets[i] = invalid_address;
+ continue;
+ }
+ }
+
+ // Defer layout here if input files are claimed by plugins. When gc
+ // is turned on this function is called twice. For the second call
+ // should_defer_layout should be false.
+ if (should_defer_layout && (shdr.get_sh_flags() & elfcpp::SHF_ALLOC))
+ {
+ gold_assert(!is_gc_pass_two);
+ this->deferred_layout_.push_back(Deferred_layout(i, sname,
+ pshdrs,
+ reloc_shndx[i],
+ reloc_type[i]));
+ // Put dummy values here; real values will be supplied by
+ // do_layout_deferred_sections.
+ out_sections[i] = reinterpret_cast<Output_section*>(2);
+ out_section_offsets[i] = invalid_address;
+ continue;
+ }
+
+ // During gc_pass_two if a section that was previously deferred is
+ // found, do not layout the section as layout_deferred_sections will
+ // do it later from gold.cc.
+ if (is_gc_pass_two
+ && (out_sections[i] == reinterpret_cast<Output_section*>(2)))
+ continue;
+
+ if (is_gc_pass_one)
+ {
+ // This is during garbage collection. The out_sections are
+ // assigned in the second call to this function.
+ out_sections[i] = reinterpret_cast<Output_section*>(1);
+ out_section_offsets[i] = invalid_address;
+ }
+ else
+ {
+ // When garbage collection is switched on the actual layout
+ // only happens in the second call.
+ this->layout_section(alayout, i, sname, shdr, reloc_shndx[i],
+ reloc_type[i]);
+ }
+ }
+
+ if (!is_gc_pass_one)
+ alayout->layout_gnu_stack(seen_gnu_stack, gnu_stack_flags);
+
+ // When doing a relocatable link handle the reloc sections at the
+ // end. Garbage collection and Identical Code Folding is not
+ // turned on for relocatable code.
+ if (emit_rels)
+ this->size_relocatable_relocs();
+
+ gold_assert(!(is_gc_or_icf) || reloc_sections.empty());
+
+ for (std::vector<unsigned int>::const_iterator p = reloc_sections.begin();
+ p != reloc_sections.end();
+ ++p)
+ {
+ unsigned int i = *p;
+ const unsigned char* pshdr;
+ pshdr = section_headers_data + i * This::shdr_size;
+ typename This::Shdr shdr(pshdr);
+
+ unsigned int data_shndx = this->adjust_shndx(shdr.get_sh_info());
+ if (data_shndx >= sec_shnum)
+ {
+ // We already warned about this above.
+ continue;
+ }
+
+ Output_section* data_section = out_sections[data_shndx];
+ if (data_section == NULL)
+ {
+ out_sections[i] = NULL;
+ out_section_offsets[i] = invalid_address;
+ continue;
+ }
+
+ Relocatable_relocs* rr = new Relocatable_relocs();
+ this->set_relocatable_relocs(i, rr);
+
+ Output_section* os = alayout->layout_reloc(this, i, shdr, data_section,
+ rr);
+ out_sections[i] = os;
+ out_section_offsets[i] = invalid_address;
+ }
+
+ // Handle the .eh_frame sections at the end.
+ gold_assert(!is_gc_pass_one || eh_frame_sections.empty());
+ for (std::vector<unsigned int>::const_iterator p = eh_frame_sections.begin();
+ p != eh_frame_sections.end();
+ ++p)
+ {
+ gold_assert(this->has_eh_frame_);
+ gold_assert(external_symbols_offset != 0);
+
+ unsigned int i = *p;
+ const unsigned char *pshdr;
+ pshdr = section_headers_data + i * This::shdr_size;
+ typename This::Shdr shdr(pshdr);
+
+ off_t off;
+ Output_section* os = alayout->layout_eh_frame(this,
+ symbols_data,
+ symbols_size,
+ symbol_names_data,
+ symbol_names_size,
+ i, shdr,
+ reloc_shndx[i],
+ reloc_type[i],
+ &off);
+ out_sections[i] = os;
+ if (off == -1)
+ {
+ // An object can contain at most one section holding exception
+ // frame information.
+ gold_assert(this->discarded_eh_frame_shndx_ == -1U);
+ this->discarded_eh_frame_shndx_ = i;
+ out_section_offsets[i] = invalid_address;
+ }
+ else
+ out_section_offsets[i] = convert_types<Address, off_t>(off);
+
+ // If this section requires special handling, and if there are
+ // relocs that apply to it, then we must do the special handling
+ // before we apply the relocs.
+ if (off == -1 && reloc_shndx[i] != 0)
+ this->set_relocs_must_follow_section_writes();
+ }
+
+ if (is_gc_pass_two)
+ {
+ delete[] gc_sd->section_headers_data;
+ delete[] gc_sd->section_names_data;
+ delete[] gc_sd->symbols_data;
+ delete[] gc_sd->symbol_names_data;
+ this->set_symbols_data(NULL);
+ }
+ else
+ {
+ delete sd->section_headers;
+ sd->section_headers = NULL;
+ delete sd->section_names;
+ sd->section_names = NULL;
+ }
+}
+
+// Layout sections whose layout was deferred while waiting for
+// input files from a plugin.
+
+template<int size, bool big_endian>
+void
+Sized_relobj<size, big_endian>::do_layout_deferred_sections(Layout* alayout)
+{
+ typename std::vector<Deferred_layout>::iterator deferred;
+
+ for (deferred = this->deferred_layout_.begin();
+ deferred != this->deferred_layout_.end();
+ ++deferred)
+ {
+ typename This::Shdr shdr(deferred->shdr_data_);
+ this->layout_section(alayout, deferred->shndx_, deferred->name_.c_str(),
+ shdr, deferred->reloc_shndx_, deferred->reloc_type_);
+ }
+
+ this->deferred_layout_.clear();
+}
+
+// Add the symbols to the symbol table.
+
+template<int size, bool big_endian>
+void
+Sized_relobj<size, big_endian>::do_add_symbols(Symbol_table* symtab,
+ Read_symbols_data* sd,
+ Layout*)
+{
+ if (sd->symbols == NULL)
+ {
+ gold_assert(sd->symbol_names == NULL);
+ return;
+ }
+
+ const int symsize = This::sym_size;
+ size_t symcount = ((sd->symbols_size - sd->external_symbols_offset)
+ / symsize);
+ if (symcount * symsize != sd->symbols_size - sd->external_symbols_offset)
+ {
+ this->error(_("size of symbols is not multiple of symbol size"));
+ return;
+ }
+
+ this->symbols_.resize(symcount);
+
+ const char* sym_names =
+ reinterpret_cast<const char*>(sd->symbol_names->data());
+ symtab->add_from_relobj(this,
+ sd->symbols->data() + sd->external_symbols_offset,
+ symcount, this->local_symbol_count_,
+ sym_names, sd->symbol_names_size,
+ &this->symbols_,
+ &this->defined_count_);
+
+ delete sd->symbols;
+ sd->symbols = NULL;
+ delete sd->symbol_names;
+ sd->symbol_names = NULL;
+}
+
+// First pass over the local symbols. Here we add their names to
+// *POOL and *DYNPOOL, and we store the symbol value in
+// THIS->LOCAL_VALUES_. This function is always called from a
+// singleton thread. This is followed by a call to
+// finalize_local_symbols.
+
+template<int size, bool big_endian>
+void
+Sized_relobj<size, big_endian>::do_count_local_symbols(Stringpool* pool,
+ Stringpool* dynpool)
+{
+ gold_assert(this->symtab_shndx_ != -1U);
+ if (this->symtab_shndx_ == 0)
+ {
+ // This object has no symbols. Weird but legal.
+ return;
+ }
+
+ // Read the symbol table section header.
+ const unsigned int sym_tab_shndx = this->symtab_shndx_;
+ typename This::Shdr symtabshdr(this,
+ this->elf_file_.section_header(sym_tab_shndx));
+ gold_assert(symtabshdr.get_sh_type() == elfcpp::SHT_SYMTAB);
+
+ // Read the local symbols.
+ const int symsize = This::sym_size;
+ const unsigned int loccount = this->local_symbol_count_;
+ gold_assert(loccount == symtabshdr.get_sh_info());
+ off_t locsize = loccount * symsize;
+ const unsigned char* psyms = this->get_view(symtabshdr.get_sh_offset(),
+ locsize, true, true);
+
+ // Read the symbol names.
+ const unsigned int strtab_shndx =
+ this->adjust_shndx(symtabshdr.get_sh_link());
+ section_size_type strtab_size;
+ const unsigned char* pnamesu = this->section_contents(strtab_shndx,
+ &strtab_size,
+ true);
+ const char* pnames = reinterpret_cast<const char*>(pnamesu);
// Loop over the local symbols.
- const std::vector<Map_to_output>& mo(this->map_to_output());
- unsigned int shnum = this->shnum();
+ const Output_sections& out_sections(this->output_sections());
+ unsigned int sec_shnum = this->shnum();
unsigned int count = 0;
+ unsigned int dyncount = 0;
// Skip the first, dummy, symbol.
- psyms += sym_size;
- for (unsigned int i = 1; i < loccount; ++i, psyms += sym_size)
+ psyms += symsize;
+ bool discard_locals = parameters->options().discard_locals();
+ for (unsigned int i = 1; i < loccount; ++i, psyms += symsize)
{
elfcpp::Sym<size, big_endian> sym(psyms);
Symbol_value<size>& lv(this->local_values_[i]);
- unsigned int shndx = sym.get_st_shndx();
- lv.set_input_shndx(shndx);
+ bool is_ordinary;
+ unsigned int shndx = this->adjust_sym_shndx(i, sym.get_st_shndx(),
+ &is_ordinary);
+ lv.set_input_shndx(shndx, is_ordinary);
+
+ if (sym.get_st_type() == elfcpp::STT_SECTION)
+ lv.set_is_section_symbol();
+ else if (sym.get_st_type() == elfcpp::STT_TLS)
+ lv.set_is_tls_symbol();
+
+ // Save the input symbol value for use in do_finalize_local_symbols().
+ lv.set_input_value(sym.get_st_value());
+
+ // Decide whether this symbol should go into the output file.
+
+ if ((shndx < sec_shnum && out_sections[shndx] == NULL)
+ || (shndx == this->discarded_eh_frame_shndx_))
+ {
+ lv.set_no_output_symtab_entry();
+ gold_assert(!lv.needs_output_dynsym_entry());
+ continue;
+ }
+
+ if (sym.get_st_type() == elfcpp::STT_SECTION)
+ {
+ lv.set_no_output_symtab_entry();
+ gold_assert(!lv.needs_output_dynsym_entry());
+ continue;
+ }
+
+ if (sym.get_st_name() >= strtab_size)
+ {
+ this->error(_("local symbol %u section name out of range: %u >= %u"),
+ i, sym.get_st_name(),
+ static_cast<unsigned int>(strtab_size));
+ lv.set_no_output_symtab_entry();
+ continue;
+ }
- if (shndx >= elfcpp::SHN_LORESERVE)
+ // If --discard-locals option is used, discard all temporary local
+ // symbols. These symbols start with system-specific local label
+ // prefixes, typically .L for ELF system. We want to be compatible
+ // with GNU ld so here we essentially use the same check in
+ // bfd_is_local_label(). The code is different because we already
+ // know that:
+ //
+ // - the symbol is local and thus cannot have global or weak binding.
+ // - the symbol is not a section symbol.
+ // - the symbol has a name.
+ //
+ // We do not discard a symbol if it needs a dynamic symbol entry.
+ const char* sname = pnames + sym.get_st_name();
+ if (discard_locals
+ && sym.get_st_type() != elfcpp::STT_FILE
+ && !lv.needs_output_dynsym_entry()
+ && parameters->target().is_local_label_name(sname))
{
- if (shndx == elfcpp::SHN_ABS)
- lv.set_output_value(sym.get_st_value());
+ lv.set_no_output_symtab_entry();
+ continue;
+ }
+
+ // Discard the local symbol if -retain_symbols_file is specified
+ // and the local symbol is not in that file.
+ if (!parameters->options().should_retain_symbol(sname))
+ {
+ lv.set_no_output_symtab_entry();
+ continue;
+ }
+
+ // Add the symbol to the symbol table string pool.
+ pool->add(sname, true, NULL);
+ ++count;
+
+ // If needed, add the symbol to the dynamic symbol table string pool.
+ if (lv.needs_output_dynsym_entry())
+ {
+ dynpool->add(sname, true, NULL);
+ ++dyncount;
+ }
+ }
+
+ this->output_local_symbol_count_ = count;
+ this->output_local_dynsym_count_ = dyncount;
+}
+
+// Finalize the local symbols. Here we set the final value in
+// THIS->LOCAL_VALUES_ and set their output symbol table indexes.
+// This function is always called from a singleton thread. The actual
+// output of the local symbols will occur in a separate task.
+
+template<int size, bool big_endian>
+unsigned int
+Sized_relobj<size, big_endian>::do_finalize_local_symbols(unsigned int index,
+ off_t off,
+ Symbol_table* symtab)
+{
+ gold_assert(off == static_cast<off_t>(align_address(off, size >> 3)));
+
+ const unsigned int loccount = this->local_symbol_count_;
+ this->local_symbol_offset_ = off;
+
+ const bool relocatable = parameters->options().relocatable();
+ const Output_sections& out_sections(this->output_sections());
+ const std::vector<Address>& out_offsets(this->section_offsets_);
+ unsigned int sec_shnum = this->shnum();
+
+ for (unsigned int i = 1; i < loccount; ++i)
+ {
+ Symbol_value<size>& lv(this->local_values_[i]);
+
+ bool is_ordinary;
+ unsigned int shndx = lv.input_shndx(&is_ordinary);
+
+ // Set the output symbol value.
+
+ if (!is_ordinary)
+ {
+ if (shndx == elfcpp::SHN_ABS || Symbol::is_common_shndx(shndx))
+ lv.set_output_value(lv.input_value());
else
{
- // FIXME: Handle SHN_XINDEX.
- fprintf(stderr,
- _("%s: %s: unknown section index %u "
- "for local symbol %u\n"),
- program_name, this->name().c_str(), shndx, i);
- gold_exit(false);
+ this->error(_("unknown section index %u for local symbol %u"),
+ shndx, i);
+ lv.set_output_value(0);
}
}
else
{
- if (shndx >= shnum)
+ if (shndx >= sec_shnum)
{
- fprintf(stderr,
- _("%s: %s: local symbol %u section index %u "
- "out of range\n"),
- program_name, this->name().c_str(), i, shndx);
- gold_exit(false);
+ this->error(_("local symbol %u section index %u out of range"),
+ i, shndx);
+ shndx = 0;
}
- Output_section* os = mo[shndx].output_section;
+ Output_section* os = out_sections[shndx];
+ Address secoffset = out_offsets[shndx];
+ if (symtab->is_section_folded(this, shndx))
+ {
+ gold_assert (os == NULL && secoffset == invalid_address);
+ // Get the os of the section it is folded onto.
+ Section_id folded = symtab->icf()->get_folded_section(this,
+ shndx);
+ gold_assert(folded.first != NULL);
+ Sized_relobj<size, big_endian>* folded_obj = reinterpret_cast
+ <Sized_relobj<size, big_endian>*>(folded.first);
+ os = folded_obj->output_section(folded.second);
+ gold_assert(os != NULL);
+ secoffset = folded_obj->get_output_section_offset(folded.second);
+ gold_assert(secoffset != invalid_address);
+ }
if (os == NULL)
{
- lv.set_output_value(0);
- lv.set_no_output_symtab_entry();
+ // This local symbol belongs to a section we are discarding.
+ // In some cases when applying relocations later, we will
+ // attempt to match it to the corresponding kept section,
+ // so we leave the input value unchanged here.
continue;
}
-
- if (mo[shndx].offset == -1)
- lv.set_input_value(sym.get_st_value());
+ else if (secoffset == invalid_address)
+ {
+ uint64_t start;
+
+ // This is a SHF_MERGE section or one which otherwise
+ // requires special handling.
+ if (shndx == this->discarded_eh_frame_shndx_)
+ {
+ // This local symbol belongs to a discarded .eh_frame
+ // section. Just treat it like the case in which
+ // os == NULL above.
+ gold_assert(this->has_eh_frame_);
+ continue;
+ }
+ else if (!lv.is_section_symbol())
+ {
+ // This is not a section symbol. We can determine
+ // the final value now.
+ lv.set_output_value(os->output_address(this, shndx,
+ lv.input_value()));
+ }
+ else if (!os->find_starting_output_address(this, shndx, &start))
+ {
+ // This is a section symbol, but apparently not one in a
+ // merged section. First check to see if this is a relaxed
+ // input section. If so, use its address. Otherwise just
+ // use the start of the output section. This happens with
+ // relocatable links when the input object has section
+ // symbols for arbitrary non-merge sections.
+ const Output_section_data* posd =
+ os->find_relaxed_input_section(this, shndx);
+ if (posd != NULL)
+ lv.set_output_value(posd->address());
+ else
+ lv.set_output_value(os->address());
+ }
+ else
+ {
+ // We have to consider the addend to determine the
+ // value to use in a relocation. START is the start
+ // of this input section.
+ Merged_symbol_value<size>* msv =
+ new Merged_symbol_value<size>(lv.input_value(), start);
+ lv.set_merged_symbol_value(msv);
+ }
+ }
+ else if (lv.is_tls_symbol())
+ lv.set_output_value(os->tls_offset()
+ + secoffset
+ + lv.input_value());
else
- lv.set_output_value(mo[shndx].output_section->address()
- + mo[shndx].offset
- + sym.get_st_value());
+ lv.set_output_value((relocatable ? 0 : os->address())
+ + secoffset
+ + lv.input_value());
}
- // Decide whether this symbol should go into the output file.
-
- if (sym.get_st_type() == elfcpp::STT_SECTION)
- {
- lv.set_no_output_symtab_entry();
- continue;
- }
+ if (lv.needs_output_symtab_entry())
+ {
+ lv.set_output_symtab_index(index);
+ ++index;
+ }
+ }
+ return index;
+}
- if (sym.get_st_name() >= strtab_size)
- {
- fprintf(stderr,
- _("%s: %s: local symbol %u section name "
- "out of range: %u >= %u\n"),
- program_name, this->name().c_str(),
- i, sym.get_st_name(),
- static_cast<unsigned int>(strtab_size));
- gold_exit(false);
- }
+// Set the output dynamic symbol table indexes for the local variables.
- const char* name = pnames + sym.get_st_name();
- pool->add(name, NULL);
- lv.set_output_symtab_index(index);
- ++index;
- ++count;
+template<int size, bool big_endian>
+unsigned int
+Sized_relobj<size, big_endian>::do_set_local_dynsym_indexes(unsigned int index)
+{
+ const unsigned int loccount = this->local_symbol_count_;
+ for (unsigned int i = 1; i < loccount; ++i)
+ {
+ Symbol_value<size>& lv(this->local_values_[i]);
+ if (lv.needs_output_dynsym_entry())
+ {
+ lv.set_output_dynsym_index(index);
+ ++index;
+ }
}
+ return index;
+}
- this->output_local_symbol_count_ = count;
+// Set the offset where local dynamic symbol information will be stored.
+// Returns the count of local symbols contributed to the symbol table by
+// this object.
- return index;
+template<int size, bool big_endian>
+unsigned int
+Sized_relobj<size, big_endian>::do_set_local_dynsym_offset(off_t off)
+{
+ gold_assert(off == static_cast<off_t>(align_address(off, size >> 3)));
+ this->local_dynsym_offset_ = off;
+ return this->output_local_dynsym_count_;
}
-// Return the value of a local symbol defined in input section SHNDX,
-// with value VALUE, adding addend ADDEND. This handles SHF_MERGE
-// sections.
+// If Symbols_data is not NULL get the section flags from here otherwise
+// get it from the file.
+
template<int size, bool big_endian>
-typename elfcpp::Elf_types<size>::Elf_Addr
-Sized_relobj<size, big_endian>::local_value(unsigned int shndx,
- Address value,
- Address addend) const
+uint64_t
+Sized_relobj<size, big_endian>::do_section_flags(unsigned int shndx)
{
- const std::vector<Map_to_output>& mo(this->map_to_output());
- Output_section* os = mo[shndx].output_section;
- if (os == NULL)
- return addend;
- gold_assert(mo[shndx].offset == -1);
- return os->output_address(this, shndx, value + addend);
+ Symbols_data* sd = this->get_symbols_data();
+ if (sd != NULL)
+ {
+ const unsigned char* pshdrs = sd->section_headers_data
+ + This::shdr_size * shndx;
+ typename This::Shdr shdr(pshdrs);
+ return shdr.get_sh_flags();
+ }
+ // If sd is NULL, read the section header from the file.
+ return this->elf_file_.section_flags(shndx);
+}
+
+// Get the section's ent size from Symbols_data. Called by get_section_contents
+// in icf.cc
+
+template<int size, bool big_endian>
+uint64_t
+Sized_relobj<size, big_endian>::do_section_entsize(unsigned int shndx)
+{
+ Symbols_data* sd = this->get_symbols_data();
+ gold_assert (sd != NULL);
+
+ const unsigned char* pshdrs = sd->section_headers_data
+ + This::shdr_size * shndx;
+ typename This::Shdr shdr(pshdrs);
+ return shdr.get_sh_entsize();
}
+
// Write out the local symbols.
template<int size, bool big_endian>
void
-Sized_relobj<size, big_endian>::write_local_symbols(Output_file* of,
- const Stringpool* sympool)
+Sized_relobj<size, big_endian>::write_local_symbols(
+ Output_file* of,
+ const Stringpool* sympool,
+ const Stringpool* dynpool,
+ Output_symtab_xindex* symtab_xindex,
+ Output_symtab_xindex* dynsym_xindex)
{
+ const bool strip_all = parameters->options().strip_all();
+ if (strip_all)
+ {
+ if (this->output_local_dynsym_count_ == 0)
+ return;
+ this->output_local_symbol_count_ = 0;
+ }
+
gold_assert(this->symtab_shndx_ != -1U);
if (this->symtab_shndx_ == 0)
{
}
// Read the symbol table section header.
- const unsigned int symtab_shndx = this->symtab_shndx_;
+ const unsigned int sym_tab_shndx = this->symtab_shndx_;
typename This::Shdr symtabshdr(this,
- this->elf_file_.section_header(symtab_shndx));
+ this->elf_file_.section_header(sym_tab_shndx));
gold_assert(symtabshdr.get_sh_type() == elfcpp::SHT_SYMTAB);
const unsigned int loccount = this->local_symbol_count_;
gold_assert(loccount == symtabshdr.get_sh_info());
// Read the local symbols.
- const int sym_size = This::sym_size;
- off_t locsize = loccount * sym_size;
+ const int symsize = This::sym_size;
+ off_t locsize = loccount * symsize;
const unsigned char* psyms = this->get_view(symtabshdr.get_sh_offset(),
- locsize, false);
+ locsize, true, false);
// Read the symbol names.
- const unsigned int strtab_shndx = symtabshdr.get_sh_link();
- off_t strtab_size;
+ const unsigned int strtab_shndx =
+ this->adjust_shndx(symtabshdr.get_sh_link());
+ section_size_type strtab_size;
const unsigned char* pnamesu = this->section_contents(strtab_shndx,
&strtab_size,
- true);
+ false);
const char* pnames = reinterpret_cast<const char*>(pnamesu);
- // Get a view into the output file.
- off_t output_size = this->output_local_symbol_count_ * sym_size;
- unsigned char* oview = of->get_output_view(this->local_symbol_offset_,
- output_size);
+ // Get views into the output file for the portions of the symbol table
+ // and the dynamic symbol table that we will be writing.
+ off_t output_size = this->output_local_symbol_count_ * symsize;
+ unsigned char* oview = NULL;
+ if (output_size > 0)
+ oview = of->get_output_view(this->local_symbol_offset_, output_size);
+
+ off_t dyn_output_size = this->output_local_dynsym_count_ * symsize;
+ unsigned char* dyn_oview = NULL;
+ if (dyn_output_size > 0)
+ dyn_oview = of->get_output_view(this->local_dynsym_offset_,
+ dyn_output_size);
- const std::vector<Map_to_output>& mo(this->map_to_output());
+ const Output_sections out_sections(this->output_sections());
gold_assert(this->local_values_.size() == loccount);
unsigned char* ov = oview;
- psyms += sym_size;
- for (unsigned int i = 1; i < loccount; ++i, psyms += sym_size)
+ unsigned char* dyn_ov = dyn_oview;
+ psyms += symsize;
+ for (unsigned int i = 1; i < loccount; ++i, psyms += symsize)
{
elfcpp::Sym<size, big_endian> isym(psyms);
- if (!this->local_values_[i].needs_output_symtab_entry())
- continue;
+ Symbol_value<size>& lv(this->local_values_[i]);
- unsigned int st_shndx = isym.get_st_shndx();
- if (st_shndx < elfcpp::SHN_LORESERVE)
+ bool is_ordinary;
+ unsigned int st_shndx = this->adjust_sym_shndx(i, isym.get_st_shndx(),
+ &is_ordinary);
+ if (is_ordinary)
{
- gold_assert(st_shndx < mo.size());
- if (mo[st_shndx].output_section == NULL)
+ gold_assert(st_shndx < out_sections.size());
+ if (out_sections[st_shndx] == NULL)
continue;
- st_shndx = mo[st_shndx].output_section->out_shndx();
+ st_shndx = out_sections[st_shndx]->out_shndx();
+ if (st_shndx >= elfcpp::SHN_LORESERVE)
+ {
+ if (lv.needs_output_symtab_entry() && !strip_all)
+ symtab_xindex->add(lv.output_symtab_index(), st_shndx);
+ if (lv.needs_output_dynsym_entry())
+ dynsym_xindex->add(lv.output_dynsym_index(), st_shndx);
+ st_shndx = elfcpp::SHN_XINDEX;
+ }
}
- elfcpp::Sym_write<size, big_endian> osym(ov);
+ // Write the symbol to the output symbol table.
+ if (!strip_all && lv.needs_output_symtab_entry())
+ {
+ elfcpp::Sym_write<size, big_endian> osym(ov);
+
+ gold_assert(isym.get_st_name() < strtab_size);
+ const char* sname = pnames + isym.get_st_name();
+ osym.put_st_name(sympool->get_offset(sname));
+ osym.put_st_value(this->local_values_[i].value(this, 0));
+ osym.put_st_size(isym.get_st_size());
+ osym.put_st_info(isym.get_st_info());
+ osym.put_st_other(isym.get_st_other());
+ osym.put_st_shndx(st_shndx);
+
+ ov += symsize;
+ }
+
+ // Write the symbol to the output dynamic symbol table.
+ if (lv.needs_output_dynsym_entry())
+ {
+ gold_assert(dyn_ov < dyn_oview + dyn_output_size);
+ elfcpp::Sym_write<size, big_endian> osym(dyn_ov);
+
+ gold_assert(isym.get_st_name() < strtab_size);
+ const char* sname = pnames + isym.get_st_name();
+ osym.put_st_name(dynpool->get_offset(sname));
+ osym.put_st_value(this->local_values_[i].value(this, 0));
+ osym.put_st_size(isym.get_st_size());
+ osym.put_st_info(isym.get_st_info());
+ osym.put_st_other(isym.get_st_other());
+ osym.put_st_shndx(st_shndx);
+
+ dyn_ov += symsize;
+ }
+ }
+
- gold_assert(isym.get_st_name() < strtab_size);
- const char* name = pnames + isym.get_st_name();
- osym.put_st_name(sympool->get_offset(name));
- osym.put_st_value(this->local_values_[i].value(this, 0));
- osym.put_st_size(isym.get_st_size());
- osym.put_st_info(isym.get_st_info());
- osym.put_st_other(isym.get_st_other());
- osym.put_st_shndx(st_shndx);
+ if (output_size > 0)
+ {
+ gold_assert(ov - oview == output_size);
+ of->write_output_view(this->local_symbol_offset_, output_size, oview);
+ }
- ov += sym_size;
+ if (dyn_output_size > 0)
+ {
+ gold_assert(dyn_ov - dyn_oview == dyn_output_size);
+ of->write_output_view(this->local_dynsym_offset_, dyn_output_size,
+ dyn_oview);
}
+}
+
+// Set *INFO to symbolic information about the offset OFFSET in the
+// section SHNDX. Return true if we found something, false if we
+// found nothing.
+
+template<int size, bool big_endian>
+bool
+Sized_relobj<size, big_endian>::get_symbol_location_info(
+ unsigned int shndx,
+ off_t sym_offset,
+ Symbol_location_info* info)
+{
+ if (this->symtab_shndx_ == 0)
+ return false;
- gold_assert(ov - oview == output_size);
+ section_size_type symbols_size;
+ const unsigned char* symbols = this->section_contents(this->symtab_shndx_,
+ &symbols_size,
+ false);
- of->write_output_view(this->local_symbol_offset_, output_size, oview);
+ unsigned int symbol_names_shndx =
+ this->adjust_shndx(this->section_link(this->symtab_shndx_));
+ section_size_type names_size;
+ const unsigned char* symbol_names_u =
+ this->section_contents(symbol_names_shndx, &names_size, false);
+ const char* symbol_names = reinterpret_cast<const char*>(symbol_names_u);
+
+ const int symsize = This::sym_size;
+ const size_t count = symbols_size / symsize;
+
+ const unsigned char* p = symbols;
+ for (size_t i = 0; i < count; ++i, p += symsize)
+ {
+ elfcpp::Sym<size, big_endian> sym(p);
+
+ if (sym.get_st_type() == elfcpp::STT_FILE)
+ {
+ if (sym.get_st_name() >= names_size)
+ info->source_file = "(invalid)";
+ else
+ info->source_file = symbol_names + sym.get_st_name();
+ continue;
+ }
+
+ bool is_ordinary;
+ unsigned int st_shndx = this->adjust_sym_shndx(i, sym.get_st_shndx(),
+ &is_ordinary);
+ if (is_ordinary
+ && st_shndx == shndx
+ && static_cast<off_t>(sym.get_st_value()) <= sym_offset
+ && (static_cast<off_t>(sym.get_st_value() + sym.get_st_size())
+ > sym_offset))
+ {
+ if (sym.get_st_name() > names_size)
+ info->enclosing_symbol_name = "(invalid)";
+ else
+ {
+ info->enclosing_symbol_name = symbol_names + sym.get_st_name();
+ if (parameters->options().do_demangle())
+ {
+ char* demangled_name = cplus_demangle(
+ info->enclosing_symbol_name.c_str(),
+ DMGL_ANSI | DMGL_PARAMS);
+ if (demangled_name != NULL)
+ {
+ info->enclosing_symbol_name.assign(demangled_name);
+ free(demangled_name);
+ }
+ }
+ }
+ return true;
+ }
+ }
+
+ return false;
+}
+
+// Look for a kept section corresponding to the given discarded section,
+// and return its output address. This is used only for relocations in
+// debugging sections. If we can't find the kept section, return 0.
+
+template<int size, bool big_endian>
+typename Sized_relobj<size, big_endian>::Address
+Sized_relobj<size, big_endian>::map_to_kept_section(
+ unsigned int shndx,
+ bool* found) const
+{
+ Relobj* kept_object;
+ unsigned int kept_shndx;
+ if (this->get_kept_comdat_section(shndx, &kept_object, &kept_shndx))
+ {
+ Sized_relobj<size, big_endian>* kept_relobj =
+ static_cast<Sized_relobj<size, big_endian>*>(kept_object);
+ Output_section* os = kept_relobj->output_section(kept_shndx);
+ Address addr_offset = kept_relobj->get_output_section_offset(kept_shndx);
+ if (os != NULL && addr_offset != invalid_address)
+ {
+ *found = true;
+ return os->address() + addr_offset;
+ }
+ }
+ *found = false;
+ return 0;
+}
+
+// Get symbol counts.
+
+template<int size, bool big_endian>
+void
+Sized_relobj<size, big_endian>::do_get_global_symbol_counts(
+ const Symbol_table*,
+ size_t* defined,
+ size_t* used) const
+{
+ *defined = this->defined_count_;
+ size_t count = 0;
+ for (Symbols::const_iterator p = this->symbols_.begin();
+ p != this->symbols_.end();
+ ++p)
+ if (*p != NULL
+ && (*p)->source() == Symbol::FROM_OBJECT
+ && (*p)->object() == this
+ && (*p)->is_defined())
+ ++count;
+ *used = count;
}
// Input_objects methods.
bool
Input_objects::add_object(Object* obj)
{
+ // Print the filename if the -t/--trace option is selected.
+ if (parameters->options().trace())
+ gold_info("%s", obj->name().c_str());
+
if (!obj->is_dynamic())
this->relobj_list_.push_back(static_cast<Relobj*>(obj));
else
{
// See if this is a duplicate SONAME.
Dynobj* dynobj = static_cast<Dynobj*>(obj);
+ const char* soname = dynobj->soname();
std::pair<Unordered_set<std::string>::iterator, bool> ins =
- this->sonames_.insert(dynobj->soname());
+ this->sonames_.insert(soname);
if (!ins.second)
{
// We have already seen a dynamic object with this soname.
this->dynobj_list_.push_back(dynobj);
}
- Target* target = obj->target();
- if (this->target_ == NULL)
- this->target_ = target;
- else if (this->target_ != target)
+ // Add this object to the cross-referencer if requested.
+ if (parameters->options().user_set_print_symbol_counts())
{
- fprintf(stderr, "%s: %s: incompatible target\n",
- program_name, obj->name().c_str());
- gold_exit(false);
+ if (this->cref_ == NULL)
+ this->cref_ = new Cref();
+ this->cref_->add_object(obj);
}
- set_parameters_size_and_endianness(target->get_size(),
- target->is_big_endian());
-
return true;
}
+// For each dynamic object, record whether we've seen all of its
+// explicit dependencies.
+
+void
+Input_objects::check_dynamic_dependencies() const
+{
+ for (Dynobj_list::const_iterator p = this->dynobj_list_.begin();
+ p != this->dynobj_list_.end();
+ ++p)
+ {
+ const Dynobj::Needed& needed((*p)->needed());
+ bool found_all = true;
+ for (Dynobj::Needed::const_iterator pneeded = needed.begin();
+ pneeded != needed.end();
+ ++pneeded)
+ {
+ if (this->sonames_.find(*pneeded) == this->sonames_.end())
+ {
+ found_all = false;
+ break;
+ }
+ }
+ (*p)->set_has_unknown_needed_entries(!found_all);
+ }
+}
+
+// Start processing an archive.
+
+void
+Input_objects::archive_start(Archive* archive)
+{
+ if (parameters->options().user_set_print_symbol_counts())
+ {
+ if (this->cref_ == NULL)
+ this->cref_ = new Cref();
+ this->cref_->add_archive_start(archive);
+ }
+}
+
+// Stop processing an archive.
+
+void
+Input_objects::archive_stop(Archive* archive)
+{
+ if (parameters->options().user_set_print_symbol_counts())
+ this->cref_->add_archive_stop(archive);
+}
+
+// Print symbol counts
+
+void
+Input_objects::print_symbol_counts(const Symbol_table* symtab) const
+{
+ if (parameters->options().user_set_print_symbol_counts()
+ && this->cref_ != NULL)
+ this->cref_->print_symbol_counts(symtab);
+}
+
// Relocate_info methods.
// Return a string describing the location of a relocation. This is
template<int size, bool big_endian>
std::string
-Relocate_info<size, big_endian>::location(size_t relnum, off_t) const
+Relocate_info<size, big_endian>::location(size_t, off_t offset) const
{
+ // See if we can get line-number information from debugging sections.
+ std::string filename;
+ std::string file_and_lineno; // Better than filename-only, if available.
+
+ Sized_dwarf_line_info<size, big_endian> line_info(this->object);
+ // This will be "" if we failed to parse the debug info for any reason.
+ file_and_lineno = line_info.addr2line(this->data_shndx, offset);
+
std::string ret(this->object->name());
- ret += ": reloc ";
- char buf[100];
- snprintf(buf, sizeof buf, "%zu", relnum);
- ret += buf;
- ret += " in reloc section ";
- snprintf(buf, sizeof buf, "%u", this->reloc_shndx);
- ret += buf;
- ret += " (" + this->object->section_name(this->reloc_shndx);
- ret += ") for section ";
- snprintf(buf, sizeof buf, "%u", this->data_shndx);
- ret += buf;
- ret += " (" + this->object->section_name(this->data_shndx) + ")";
+ ret += ':';
+ Symbol_location_info info;
+ if (this->object->get_symbol_location_info(this->data_shndx, offset, &info))
+ {
+ ret += " in function ";
+ ret += info.enclosing_symbol_name;
+ ret += ":";
+ filename = info.source_file;
+ }
+
+ if (!file_and_lineno.empty())
+ ret += file_and_lineno;
+ else
+ {
+ if (!filename.empty())
+ ret += filename;
+ ret += "(";
+ ret += this->object->section_name(this->data_shndx);
+ char buf[100];
+ // Offsets into sections have to be positive.
+ snprintf(buf, sizeof(buf), "+0x%lx", static_cast<long>(offset));
+ ret += buf;
+ ret += ")";
+ }
return ret;
}
template<int size, bool big_endian>
Object*
make_elf_sized_object(const std::string& name, Input_file* input_file,
- off_t offset, const elfcpp::Ehdr<size, big_endian>& ehdr)
+ off_t offset, const elfcpp::Ehdr<size, big_endian>& ehdr,
+ bool* punconfigured)
{
- int et = ehdr.get_e_type();
- if (et == elfcpp::ET_REL)
- {
- Sized_relobj<size, big_endian>* obj =
- new Sized_relobj<size, big_endian>(name, input_file, offset, ehdr);
- obj->setup(ehdr);
- return obj;
- }
- else if (et == elfcpp::ET_DYN)
- {
- Sized_dynobj<size, big_endian>* obj =
- new Sized_dynobj<size, big_endian>(name, input_file, offset, ehdr);
- obj->setup(ehdr);
- return obj;
- }
- else
+ Target* target = select_target(ehdr.get_e_machine(), size, big_endian,
+ ehdr.get_e_ident()[elfcpp::EI_OSABI],
+ ehdr.get_e_ident()[elfcpp::EI_ABIVERSION]);
+ if (target == NULL)
+ gold_fatal(_("%s: unsupported ELF machine number %d"),
+ name.c_str(), ehdr.get_e_machine());
+
+ if (!parameters->target_valid())
+ set_parameters_target(target);
+ else if (target != ¶meters->target())
{
- fprintf(stderr, _("%s: %s: unsupported ELF file type %d\n"),
- program_name, name.c_str(), et);
- gold_exit(false);
+ if (punconfigured != NULL)
+ *punconfigured = true;
+ else
+ gold_error(_("%s: incompatible target"), name.c_str());
+ return NULL;
}
+
+ return target->make_elf_object<size, big_endian>(name, input_file, offset,
+ ehdr);
}
} // End anonymous namespace.
namespace gold
{
-// Read an ELF file and return the appropriate instance of Object.
+// Return whether INPUT_FILE is an ELF object.
-Object*
-make_elf_object(const std::string& name, Input_file* input_file, off_t offset,
- const unsigned char* p, off_t bytes)
+bool
+is_elf_object(Input_file* input_file, off_t offset,
+ const unsigned char** start, int *read_size)
{
- if (bytes < elfcpp::EI_NIDENT)
- {
- fprintf(stderr, _("%s: %s: ELF file too short\n"),
- program_name, name.c_str());
- gold_exit(false);
- }
+ off_t filesize = input_file->file().filesize();
+ int want = elfcpp::Elf_recognizer::max_header_size;
+ if (filesize - offset < want)
+ want = filesize - offset;
- int v = p[elfcpp::EI_VERSION];
- if (v != elfcpp::EV_CURRENT)
- {
- if (v == elfcpp::EV_NONE)
- fprintf(stderr, _("%s: %s: invalid ELF version 0\n"),
- program_name, name.c_str());
- else
- fprintf(stderr, _("%s: %s: unsupported ELF version %d\n"),
- program_name, name.c_str(), v);
- gold_exit(false);
- }
+ const unsigned char* p = input_file->file().get_view(offset, 0, want,
+ true, false);
+ *start = p;
+ *read_size = want;
- int c = p[elfcpp::EI_CLASS];
- if (c == elfcpp::ELFCLASSNONE)
- {
- fprintf(stderr, _("%s: %s: invalid ELF class 0\n"),
- program_name, name.c_str());
- gold_exit(false);
- }
- else if (c != elfcpp::ELFCLASS32
- && c != elfcpp::ELFCLASS64)
- {
- fprintf(stderr, _("%s: %s: unsupported ELF class %d\n"),
- program_name, name.c_str(), c);
- gold_exit(false);
- }
+ return elfcpp::Elf_recognizer::is_elf_file(p, want);
+}
- int d = p[elfcpp::EI_DATA];
- if (d == elfcpp::ELFDATANONE)
- {
- fprintf(stderr, _("%s: %s: invalid ELF data encoding\n"),
- program_name, name.c_str());
- gold_exit(false);
- }
- else if (d != elfcpp::ELFDATA2LSB
- && d != elfcpp::ELFDATA2MSB)
+// Read an ELF file and return the appropriate instance of Object.
+
+Object*
+make_elf_object(const std::string& name, Input_file* input_file, off_t offset,
+ const unsigned char* p, section_offset_type bytes,
+ bool* punconfigured)
+{
+ if (punconfigured != NULL)
+ *punconfigured = false;
+
+ std::string error;
+ bool big_endian = false;
+ int size = 0;
+ if (!elfcpp::Elf_recognizer::is_valid_header(p, bytes, &size,
+ &big_endian, &error))
{
- fprintf(stderr, _("%s: %s: unsupported ELF data encoding %d\n"),
- program_name, name.c_str(), d);
- gold_exit(false);
+ gold_error(_("%s: %s"), name.c_str(), error.c_str());
+ return NULL;
}
- bool big_endian = d == elfcpp::ELFDATA2MSB;
-
- if (c == elfcpp::ELFCLASS32)
+ if (size == 32)
{
- if (bytes < elfcpp::Elf_sizes<32>::ehdr_size)
- {
- fprintf(stderr, _("%s: %s: ELF file too short\n"),
- program_name, name.c_str());
- gold_exit(false);
- }
if (big_endian)
{
#ifdef HAVE_TARGET_32_BIG
elfcpp::Ehdr<32, true> ehdr(p);
return make_elf_sized_object<32, true>(name, input_file,
- offset, ehdr);
+ offset, ehdr, punconfigured);
#else
- fprintf(stderr,
- _("%s: %s: not configured to support 32-bit big-endian object\n"),
- program_name, name.c_str());
- gold_exit(false);
+ if (punconfigured != NULL)
+ *punconfigured = true;
+ else
+ gold_error(_("%s: not configured to support "
+ "32-bit big-endian object"),
+ name.c_str());
+ return NULL;
#endif
}
else
#ifdef HAVE_TARGET_32_LITTLE
elfcpp::Ehdr<32, false> ehdr(p);
return make_elf_sized_object<32, false>(name, input_file,
- offset, ehdr);
+ offset, ehdr, punconfigured);
#else
- fprintf(stderr,
- _("%s: %s: not configured to support 32-bit little-endian object\n"),
- program_name, name.c_str());
- gold_exit(false);
+ if (punconfigured != NULL)
+ *punconfigured = true;
+ else
+ gold_error(_("%s: not configured to support "
+ "32-bit little-endian object"),
+ name.c_str());
+ return NULL;
#endif
}
}
- else
+ else if (size == 64)
{
- if (bytes < elfcpp::Elf_sizes<32>::ehdr_size)
- {
- fprintf(stderr, _("%s: %s: ELF file too short\n"),
- program_name, name.c_str());
- gold_exit(false);
- }
if (big_endian)
{
#ifdef HAVE_TARGET_64_BIG
elfcpp::Ehdr<64, true> ehdr(p);
return make_elf_sized_object<64, true>(name, input_file,
- offset, ehdr);
+ offset, ehdr, punconfigured);
#else
- fprintf(stderr,
- _("%s: %s: not configured to support 64-bit big-endian object\n"),
- program_name, name.c_str());
- gold_exit(false);
+ if (punconfigured != NULL)
+ *punconfigured = true;
+ else
+ gold_error(_("%s: not configured to support "
+ "64-bit big-endian object"),
+ name.c_str());
+ return NULL;
#endif
}
else
#ifdef HAVE_TARGET_64_LITTLE
elfcpp::Ehdr<64, false> ehdr(p);
return make_elf_sized_object<64, false>(name, input_file,
- offset, ehdr);
+ offset, ehdr, punconfigured);
#else
- fprintf(stderr,
- _("%s: %s: not configured to support 64-bit little-endian object\n"),
- program_name, name.c_str());
- gold_exit(false);
+ if (punconfigured != NULL)
+ *punconfigured = true;
+ else
+ gold_error(_("%s: not configured to support "
+ "64-bit little-endian object"),
+ name.c_str());
+ return NULL;
#endif
}
}
+ else
+ gold_unreachable();
}
-// Instantiate the templates we need. We could use the configure
-// script to restrict this to only the ones for implemented targets.
+// Instantiate the templates we need.
+
+#ifdef HAVE_TARGET_32_LITTLE
+template
+void
+Object::read_section_data<32, false>(elfcpp::Elf_file<32, false, Object>*,
+ Read_symbols_data*);
+#endif
+
+#ifdef HAVE_TARGET_32_BIG
+template
+void
+Object::read_section_data<32, true>(elfcpp::Elf_file<32, true, Object>*,
+ Read_symbols_data*);
+#endif
+
+#ifdef HAVE_TARGET_64_LITTLE
+template
+void
+Object::read_section_data<64, false>(elfcpp::Elf_file<64, false, Object>*,
+ Read_symbols_data*);
+#endif
+
+#ifdef HAVE_TARGET_64_BIG
+template
+void
+Object::read_section_data<64, true>(elfcpp::Elf_file<64, true, Object>*,
+ Read_symbols_data*);
+#endif
#ifdef HAVE_TARGET_32_LITTLE
template