ChangeLog rotatation and copyright year update
[deliverable/binutils-gdb.git] / ld / ldexp.c
index e45c47068c988484d957bea5f7337625a65d7cd3..f2c8620a4651aa2604b66291513db4c69697ad76 100644 (file)
@@ -1,25 +1,24 @@
 /* This module handles expression trees.
-   Copyright 1991, 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999, 2000,
-   2001, 2002
-   Free Software Foundation, Inc.
+   Copyright (C) 1991-2015 Free Software Foundation, Inc.
    Written by Steve Chamberlain of Cygnus Support <sac@cygnus.com>.
 
-This file is part of GLD, the Gnu Linker.
+   This file is part of the GNU Binutils.
 
-GLD 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 2, or (at your option)
-any later version.
+   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.
 
-GLD 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.
+   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, write to the Free Software
+   Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston,
+   MA 02110-1301, USA.  */
 
-You should have received a copy of the GNU General Public License
-along with GLD; see the file COPYING.  If not, write to the Free
-Software Foundation, 59 Temple Place - Suite 330, Boston, MA
-02111-1307, USA.  */
 
 /* This module is in charge of working out the contents of expressions.
 
@@ -28,67 +27,50 @@ Software Foundation, 59 Temple Place - Suite 330, Boston, MA
    which contains a value, a section to which it is relative and a
    valid bit.  */
 
-#include "bfd.h"
 #include "sysdep.h"
+#include "bfd.h"
 #include "bfdlink.h"
 
 #include "ld.h"
 #include "ldmain.h"
 #include "ldmisc.h"
 #include "ldexp.h"
-#include "ldgram.h"
+#include "ldlex.h"
+#include <ldgram.h>
 #include "ldlang.h"
 #include "libiberty.h"
 #include "safe-ctype.h"
 
-static void exp_print_token PARAMS ((token_code_type code, int infix_p));
-static void make_abs PARAMS ((etree_value_type *ptr));
-static etree_value_type new_abs PARAMS ((bfd_vma value));
-static void check PARAMS ((lang_output_section_statement_type *os,
-                          const char *name, const char *op));
-static etree_value_type new_rel
-  PARAMS ((bfd_vma, char *, lang_output_section_statement_type *section));
-static etree_value_type new_rel_from_section
-  PARAMS ((bfd_vma value, lang_output_section_statement_type *section));
-static etree_value_type fold_unary
-  PARAMS ((etree_type *tree,
-          lang_output_section_statement_type *current_section,
-          lang_phase_type allocation_done,
-          bfd_vma dot, bfd_vma *dotp));
-static etree_value_type fold_binary
-  PARAMS ((etree_type *tree,
-          lang_output_section_statement_type *current_section,
-          lang_phase_type allocation_done,
-          bfd_vma dot, bfd_vma *dotp));
-static etree_value_type fold_trinary
-  PARAMS ((etree_type *tree,
-          lang_output_section_statement_type *current_section,
-          lang_phase_type allocation_done,
-          bfd_vma dot, bfd_vma *dotp));
-static etree_value_type fold_name
-  PARAMS ((etree_type *tree,
-          lang_output_section_statement_type *current_section,
-          lang_phase_type allocation_done,
-          bfd_vma dot));
-static etree_value_type exp_fold_tree_no_dot
-  PARAMS ((etree_type *tree,
-          lang_output_section_statement_type *current_section,
-          lang_phase_type allocation_done));
-
-struct exp_data_seg exp_data_seg;
+static void exp_fold_tree_1 (etree_type *);
+static bfd_vma align_n (bfd_vma, bfd_vma);
+
+segment_type *segments;
+
+struct ldexp_control expld;
+
+/* This structure records symbols for which we need to keep track of
+   definedness for use in the DEFINED () test.  */
+
+struct definedness_hash_entry
+{
+  struct bfd_hash_entry root;
+  unsigned int by_object : 1;
+  unsigned int by_script : 1;
+  unsigned int iteration : 1;
+};
+
+static struct bfd_hash_table definedness_table;
 
 /* Print the string representation of the given token.  Surround it
-   with spaces if INFIX_P is true.  */
+   with spaces if INFIX_P is TRUE.  */
 
 static void
-exp_print_token (code, infix_p)
-     token_code_type code;
-     int infix_p;
+exp_print_token (token_code_type code, int infix_p)
 {
   static const struct
   {
     token_code_type code;
-    char * name;
+    const char * name;
   }
   table[] =
   {
@@ -110,6 +92,7 @@ exp_print_token (code, infix_p)
     { GE, ">=" },
     { LSHIFT, "<<" },
     { RSHIFT, ">>" },
+    { LOG2CEIL, "LOG2CEIL" },
     { ALIGN_K, "ALIGN" },
     { BLOCK, "BLOCK" },
     { QUAD, "QUAD" },
@@ -126,13 +109,22 @@ exp_print_token (code, infix_p)
     { MAP, "MAP" },
     { ENTRY, "ENTRY" },
     { NEXT, "NEXT" },
+    { ALIGNOF, "ALIGNOF" },
     { SIZEOF, "SIZEOF" },
     { ADDR, "ADDR" },
     { LOADADDR, "LOADADDR" },
-    { MAX_K, "MAX_K" },
-    { REL, "relocateable" },
+    { CONSTANT, "CONSTANT" },
+    { ABSOLUTE, "ABSOLUTE" },
+    { MAX_K, "MAX" },
+    { MIN_K, "MIN" },
+    { ASSERT_K, "ASSERT" },
+    { REL, "relocatable" },
     { DATA_SEGMENT_ALIGN, "DATA_SEGMENT_ALIGN" },
-    { DATA_SEGMENT_END, "DATA_SEGMENT_END" }
+    { DATA_SEGMENT_RELRO_END, "DATA_SEGMENT_RELRO_END" },
+    { DATA_SEGMENT_END, "DATA_SEGMENT_END" },
+    { ORIGIN, "ORIGIN" },
+    { LENGTH, "LENGTH" },
+    { SEGMENT_START, "SEGMENT_START" }
   };
   unsigned int idx;
 
@@ -155,183 +147,250 @@ exp_print_token (code, infix_p)
 }
 
 static void
-make_abs (ptr)
-     etree_value_type *ptr;
+make_log2ceil (void)
 {
-  asection *s = ptr->section->bfd_section;
-  ptr->value += s->vma;
-  ptr->section = abs_output_section;
+  bfd_vma value = expld.result.value;
+  bfd_vma result = -1;
+  bfd_boolean round_up = FALSE;
+
+  do
+    {
+      result++;
+      /* If more than one bit is set in the value we will need to round up.  */
+      if ((value > 1) && (value & 1))
+       round_up = TRUE;
+    }
+  while (value >>= 1);
+
+  if (round_up)
+    result += 1;
+  expld.result.section = NULL;
+  expld.result.value = result;
 }
 
-static etree_value_type
-new_abs (value)
-     bfd_vma value;
+static void
+make_abs (void)
 {
-  etree_value_type new;
-  new.valid_p = true;
-  new.section = abs_output_section;
-  new.value = value;
-  return new;
+  if (expld.result.section != NULL)
+    expld.result.value += expld.result.section->vma;
+  expld.result.section = bfd_abs_section_ptr;
 }
 
 static void
-check (os, name, op)
-     lang_output_section_statement_type *os;
-     const char *name;
-     const char *op;
+new_abs (bfd_vma value)
 {
-  if (os == NULL)
-    einfo (_("%F%P: %s uses undefined section %s\n"), op, name);
-  if (! os->processed)
-    einfo (_("%F%P: %s forward reference of section %s\n"), op, name);
+  expld.result.valid_p = TRUE;
+  expld.result.section = bfd_abs_section_ptr;
+  expld.result.value = value;
+  expld.result.str = NULL;
 }
 
 etree_type *
-exp_intop (value)
-     bfd_vma value;
+exp_intop (bfd_vma value)
 {
-  etree_type *new = (etree_type *) stat_alloc (sizeof (new->value));
-  new->type.node_code = INT;
-  new->value.value = value;
-  new->value.str = NULL;
-  new->type.node_class = etree_value;
-  return new;
+  etree_type *new_e = (etree_type *) stat_alloc (sizeof (new_e->value));
+  new_e->type.node_code = INT;
+  new_e->type.filename = ldlex_filename ();
+  new_e->type.lineno = lineno;
+  new_e->value.value = value;
+  new_e->value.str = NULL;
+  new_e->type.node_class = etree_value;
+  return new_e;
 }
 
 etree_type *
-exp_bigintop (value, str)
-     bfd_vma value;
-     char *str;
+exp_bigintop (bfd_vma value, char *str)
 {
-  etree_type *new = (etree_type *) stat_alloc (sizeof (new->value));
-  new->type.node_code = INT;
-  new->value.value = value;
-  new->value.str = str;
-  new->type.node_class = etree_value;
-  return new;
+  etree_type *new_e = (etree_type *) stat_alloc (sizeof (new_e->value));
+  new_e->type.node_code = INT;
+  new_e->type.filename = ldlex_filename ();
+  new_e->type.lineno = lineno;
+  new_e->value.value = value;
+  new_e->value.str = str;
+  new_e->type.node_class = etree_value;
+  return new_e;
 }
 
-/* Build an expression representing an unnamed relocateable value.  */
+/* Build an expression representing an unnamed relocatable value.  */
 
 etree_type *
-exp_relop (section, value)
-     asection *section;
-     bfd_vma value;
+exp_relop (asection *section, bfd_vma value)
+{
+  etree_type *new_e = (etree_type *) stat_alloc (sizeof (new_e->rel));
+  new_e->type.node_code = REL;
+  new_e->type.filename = ldlex_filename ();
+  new_e->type.lineno = lineno;
+  new_e->type.node_class = etree_rel;
+  new_e->rel.section = section;
+  new_e->rel.value = value;
+  return new_e;
+}
+
+static void
+new_number (bfd_vma value)
 {
-  etree_type *new = (etree_type *) stat_alloc (sizeof (new->rel));
-  new->type.node_code = REL;
-  new->type.node_class = etree_rel;
-  new->rel.section = section;
-  new->rel.value = value;
-  return new;
+  expld.result.valid_p = TRUE;
+  expld.result.value = value;
+  expld.result.str = NULL;
+  expld.result.section = NULL;
 }
 
-static etree_value_type
-new_rel (value, str, section)
-     bfd_vma value;
-     char *str;
-     lang_output_section_statement_type *section;
+static void
+new_rel (bfd_vma value, asection *section)
 {
-  etree_value_type new;
-  new.valid_p = true;
-  new.value = value;
-  new.str = str;
-  new.section = section;
-  return new;
+  expld.result.valid_p = TRUE;
+  expld.result.value = value;
+  expld.result.str = NULL;
+  expld.result.section = section;
 }
 
-static etree_value_type
-new_rel_from_section (value, section)
-     bfd_vma value;
-     lang_output_section_statement_type *section;
+static void
+new_rel_from_abs (bfd_vma value)
 {
-  etree_value_type new;
-  new.valid_p = true;
-  new.value = value;
-  new.str = NULL;
-  new.section = section;
+  asection *s = expld.section;
+
+  if (s == bfd_abs_section_ptr && expld.phase == lang_final_phase_enum)
+    s = section_for_dot ();
+  expld.result.valid_p = TRUE;
+  expld.result.value = value - s->vma;
+  expld.result.str = NULL;
+  expld.result.section = s;
+}
 
-  new.value -= section->bfd_section->vma;
+/* New-function for the definedness hash table.  */
 
-  return new;
+static struct bfd_hash_entry *
+definedness_newfunc (struct bfd_hash_entry *entry,
+                    struct bfd_hash_table *table ATTRIBUTE_UNUSED,
+                    const char *name ATTRIBUTE_UNUSED)
+{
+  struct definedness_hash_entry *ret = (struct definedness_hash_entry *) entry;
+
+  if (ret == NULL)
+    ret = (struct definedness_hash_entry *)
+      bfd_hash_allocate (table, sizeof (struct definedness_hash_entry));
+
+  if (ret == NULL)
+    einfo (_("%P%F: bfd_hash_allocate failed creating symbol %s\n"), name);
+
+  ret->by_object = 0;
+  ret->by_script = 0;
+  ret->iteration = 0;
+  return &ret->root;
 }
 
-static etree_value_type
-fold_unary (tree, current_section, allocation_done, dot, dotp)
-     etree_type *tree;
-     lang_output_section_statement_type *current_section;
-     lang_phase_type allocation_done;
-     bfd_vma dot;
-     bfd_vma *dotp;
+/* Called during processing of linker script script expressions.
+   For symbols assigned in a linker script, return a struct describing
+   where the symbol is defined relative to the current expression,
+   otherwise return NULL.  */
+
+static struct definedness_hash_entry *
+symbol_defined (const char *name)
 {
-  etree_value_type result;
+  return ((struct definedness_hash_entry *)
+         bfd_hash_lookup (&definedness_table, name, FALSE, FALSE));
+}
+
+/* Update the definedness state of NAME.  Return FALSE if script symbol
+   is multiply defining a strong symbol in an object.  */
+
+static bfd_boolean
+update_definedness (const char *name, struct bfd_link_hash_entry *h)
+{
+  bfd_boolean ret;
+  struct definedness_hash_entry *defentry
+    = (struct definedness_hash_entry *)
+    bfd_hash_lookup (&definedness_table, name, TRUE, FALSE);
+
+  if (defentry == NULL)
+    einfo (_("%P%F: bfd_hash_lookup failed creating symbol %s\n"), name);
+
+  /* If the symbol was already defined, and not by a script, then it
+     must be defined by an object file or by the linker target code.  */
+  ret = TRUE;
+  if (!defentry->by_script
+      && (h->type == bfd_link_hash_defined
+         || h->type == bfd_link_hash_defweak
+         || h->type == bfd_link_hash_common))
+    {
+      defentry->by_object = 1;
+      if (h->type == bfd_link_hash_defined
+         && h->u.def.section->output_section != NULL
+         && !h->linker_def)
+       ret = FALSE;
+    }
+
+  defentry->by_script = 1;
+  defentry->iteration = lang_statement_iteration;
+  return ret;
+}
 
-  result = exp_fold_tree (tree->unary.child,
-                         current_section,
-                         allocation_done, dot, dotp);
-  if (result.valid_p)
+static void
+fold_unary (etree_type *tree)
+{
+  exp_fold_tree_1 (tree->unary.child);
+  if (expld.result.valid_p)
     {
       switch (tree->type.node_code)
        {
        case ALIGN_K:
-         if (allocation_done != lang_first_phase_enum)
-           result = new_rel_from_section (align_n (dot, result.value),
-                                          current_section);
+         if (expld.phase != lang_first_phase_enum)
+           new_rel_from_abs (align_n (expld.dot, expld.result.value));
          else
-           result.valid_p = false;
+           expld.result.valid_p = FALSE;
          break;
 
        case ABSOLUTE:
-         if (allocation_done != lang_first_phase_enum)
-           {
-             result.value += result.section->bfd_section->vma;
-             result.section = abs_output_section;
-           }
-         else
-           result.valid_p = false;
+         make_abs ();
+         break;
+
+       case LOG2CEIL:
+         make_log2ceil ();
          break;
 
        case '~':
-         make_abs (&result);
-         result.value = ~result.value;
+         expld.result.value = ~expld.result.value;
          break;
 
        case '!':
-         make_abs (&result);
-         result.value = !result.value;
+         expld.result.value = !expld.result.value;
          break;
 
        case '-':
-         make_abs (&result);
-         result.value = -result.value;
+         expld.result.value = -expld.result.value;
          break;
 
        case NEXT:
          /* Return next place aligned to value.  */
-         if (allocation_done == lang_allocating_phase_enum)
+         if (expld.phase != lang_first_phase_enum)
            {
-             make_abs (&result);
-             result.value = align_n (dot, result.value);
+             make_abs ();
+             expld.result.value = align_n (expld.dot, expld.result.value);
            }
          else
-           result.valid_p = false;
+           expld.result.valid_p = FALSE;
          break;
 
        case DATA_SEGMENT_END:
-         if (allocation_done != lang_first_phase_enum
-             && current_section == abs_output_section
-             && (exp_data_seg.phase == exp_dataseg_align_seen
-                 || exp_data_seg.phase == exp_dataseg_adjust
-                 || allocation_done != lang_allocating_phase_enum))
+         if (expld.phase == lang_first_phase_enum
+             || expld.section != bfd_abs_section_ptr)
            {
-             if (exp_data_seg.phase == exp_dataseg_align_seen)
-               {
-                 exp_data_seg.phase = exp_dataseg_end_seen;
-                 exp_data_seg.end = result.value;
-               }
+             expld.result.valid_p = FALSE;
+           }
+         else if (expld.dataseg.phase == exp_dataseg_align_seen
+                  || expld.dataseg.phase == exp_dataseg_relro_seen)
+           {
+             expld.dataseg.phase = exp_dataseg_end_seen;
+             expld.dataseg.end = expld.result.value;
+           }
+         else if (expld.dataseg.phase == exp_dataseg_done
+                  || expld.dataseg.phase == exp_dataseg_adjust
+                  || expld.dataseg.phase == exp_dataseg_relro_adjust)
+           {
+             /* OK.  */
            }
          else
-           result.valid_p = false;
+           expld.result.valid_p = FALSE;
          break;
 
        default:
@@ -339,381 +398,609 @@ fold_unary (tree, current_section, allocation_done, dot, dotp)
          break;
        }
     }
-
-  return result;
 }
 
-static etree_value_type
-fold_binary (tree, current_section, allocation_done, dot, dotp)
-     etree_type *tree;
-     lang_output_section_statement_type *current_section;
-     lang_phase_type allocation_done;
-     bfd_vma dot;
-     bfd_vma *dotp;
+static void
+fold_binary (etree_type *tree)
 {
-  etree_value_type result;
-
-  result = exp_fold_tree (tree->binary.lhs, current_section,
-                         allocation_done, dot, dotp);
-  if (result.valid_p)
+  etree_value_type lhs;
+  exp_fold_tree_1 (tree->binary.lhs);
+
+  /* The SEGMENT_START operator is special because its first
+     operand is a string, not the name of a symbol.  Note that the
+     operands have been swapped, so binary.lhs is second (default)
+     operand, binary.rhs is first operand.  */
+  if (expld.result.valid_p && tree->type.node_code == SEGMENT_START)
     {
-      etree_value_type other;
+      const char *segment_name;
+      segment_type *seg;
+
+      /* Check to see if the user has overridden the default
+        value.  */
+      segment_name = tree->binary.rhs->name.name;
+      for (seg = segments; seg; seg = seg->next)
+       if (strcmp (seg->name, segment_name) == 0)
+         {
+           if (!seg->used
+               && config.magic_demand_paged
+               && (seg->value % config.maxpagesize) != 0)
+             einfo (_("%P: warning: address of `%s' isn't multiple of maximum page size\n"),
+                    segment_name);
+           seg->used = TRUE;
+           new_rel_from_abs (seg->value);
+           break;
+         }
+      return;
+    }
+
+  lhs = expld.result;
+  exp_fold_tree_1 (tree->binary.rhs);
+  expld.result.valid_p &= lhs.valid_p;
 
-      other = exp_fold_tree (tree->binary.rhs,
-                            current_section,
-                            allocation_done, dot, dotp);
-      if (other.valid_p)
+  if (expld.result.valid_p)
+    {
+      if (lhs.section != expld.result.section)
        {
-         /* If the values are from different sections, or this is an
-            absolute expression, make both the source arguments
-            absolute.  However, adding or subtracting an absolute
-            value from a relative value is meaningful, and is an
-            exception.  */
-         if (current_section != abs_output_section
-             && (other.section == abs_output_section
-                 || (result.section == abs_output_section
-                     && tree->type.node_code == '+'))
-             && (tree->type.node_code == '+'
-                 || tree->type.node_code == '-'))
+         /* If the values are from different sections, and neither is
+            just a number, make both the source arguments absolute.  */
+         if (expld.result.section != NULL
+             && lhs.section != NULL)
            {
-             if (other.section != abs_output_section)
-               {
-                 /* Keep the section of the other term.  */
-                 if (tree->type.node_code == '+')
-                   other.value = result.value + other.value;
-                 else
-                   other.value = result.value - other.value;
-                 return other;
-               }
+             make_abs ();
+             lhs.value += lhs.section->vma;
+             lhs.section = bfd_abs_section_ptr;
            }
-         else if (result.section != other.section
-                  || current_section == abs_output_section)
+
+         /* If the rhs is just a number, keep the lhs section.  */
+         else if (expld.result.section == NULL)
            {
-             make_abs (&result);
-             make_abs (&other);
+             expld.result.section = lhs.section;
+             /* Make this NULL so that we know one of the operands
+                was just a number, for later tests.  */
+             lhs.section = NULL;
            }
+       }
+      /* At this point we know that both operands have the same
+        section, or at least one of them is a plain number.  */
+
+      switch (tree->type.node_code)
+       {
+         /* Arithmetic operators, bitwise AND, bitwise OR and XOR
+            keep the section of one of their operands only when the
+            other operand is a plain number.  Losing the section when
+            operating on two symbols, ie. a result of a plain number,
+            is required for subtraction and XOR.  It's justifiable
+            for the other operations on the grounds that adding,
+            multiplying etc. two section relative values does not
+            really make sense unless they are just treated as
+            numbers.
+            The same argument could be made for many expressions
+            involving one symbol and a number.  For example,
+            "1 << x" and "100 / x" probably should not be given the
+            section of x.  The trouble is that if we fuss about such
+            things the rules become complex and it is onerous to
+            document ld expression evaluation.  */
+#define BOP(x, y) \
+       case x:                                                 \
+         expld.result.value = lhs.value y expld.result.value;  \
+         if (expld.result.section == lhs.section)              \
+           expld.result.section = NULL;                        \
+         break;
+
+         /* Comparison operators, logical AND, and logical OR always
+            return a plain number.  */
+#define BOPN(x, y) \
+       case x:                                                 \
+         expld.result.value = lhs.value y expld.result.value;  \
+         expld.result.section = NULL;                          \
+         break;
+
+         BOP ('+', +);
+         BOP ('*', *);
+         BOP ('-', -);
+         BOP (LSHIFT, <<);
+         BOP (RSHIFT, >>);
+         BOP ('&', &);
+         BOP ('^', ^);
+         BOP ('|', |);
+         BOPN (EQ, ==);
+         BOPN (NE, !=);
+         BOPN ('<', <);
+         BOPN ('>', >);
+         BOPN (LE, <=);
+         BOPN (GE, >=);
+         BOPN (ANDAND, &&);
+         BOPN (OROR, ||);
+
+       case '%':
+         if (expld.result.value != 0)
+           expld.result.value = ((bfd_signed_vma) lhs.value
+                                 % (bfd_signed_vma) expld.result.value);
+         else if (expld.phase != lang_mark_phase_enum)
+           einfo (_("%F%S %% by zero\n"), tree->binary.rhs);
+         if (expld.result.section == lhs.section)
+           expld.result.section = NULL;
+         break;
+
+       case '/':
+         if (expld.result.value != 0)
+           expld.result.value = ((bfd_signed_vma) lhs.value
+                                 / (bfd_signed_vma) expld.result.value);
+         else if (expld.phase != lang_mark_phase_enum)
+           einfo (_("%F%S / by zero\n"), tree->binary.rhs);
+         if (expld.result.section == lhs.section)
+           expld.result.section = NULL;
+         break;
+
+       case MAX_K:
+         if (lhs.value > expld.result.value)
+           expld.result.value = lhs.value;
+         break;
+
+       case MIN_K:
+         if (lhs.value < expld.result.value)
+           expld.result.value = lhs.value;
+         break;
 
-         switch (tree->type.node_code)
+       case ALIGN_K:
+         expld.result.value = align_n (lhs.value, expld.result.value);
+         break;
+
+       case DATA_SEGMENT_ALIGN:
+         expld.dataseg.relro = exp_dataseg_relro_start;
+         if (expld.phase == lang_first_phase_enum
+             || expld.section != bfd_abs_section_ptr)
+           expld.result.valid_p = FALSE;
+         else
            {
-           case '%':
-             if (other.value == 0)
-               einfo (_("%F%S %% by zero\n"));
-             result.value = ((bfd_signed_vma) result.value
-                             % (bfd_signed_vma) other.value);
-             break;
-
-           case '/':
-             if (other.value == 0)
-               einfo (_("%F%S / by zero\n"));
-             result.value = ((bfd_signed_vma) result.value
-                             / (bfd_signed_vma) other.value);
-             break;
-
-#define BOP(x,y) case x : result.value = result.value y other.value; break;
-             BOP ('+', +);
-             BOP ('*', *);
-             BOP ('-', -);
-             BOP (LSHIFT, <<);
-             BOP (RSHIFT, >>);
-             BOP (EQ, ==);
-             BOP (NE, !=);
-             BOP ('<', <);
-             BOP ('>', >);
-             BOP (LE, <=);
-             BOP (GE, >=);
-             BOP ('&', &);
-             BOP ('^', ^);
-             BOP ('|', |);
-             BOP (ANDAND, &&);
-             BOP (OROR, ||);
-
-           case MAX_K:
-             if (result.value < other.value)
-               result = other;
-             break;
-
-           case MIN_K:
-             if (result.value > other.value)
-               result = other;
-             break;
-
-           case DATA_SEGMENT_ALIGN:
-             if (allocation_done != lang_first_phase_enum
-                 && current_section == abs_output_section
-                 && (exp_data_seg.phase == exp_dataseg_none
-                     || exp_data_seg.phase == exp_dataseg_adjust
-                     || allocation_done != lang_allocating_phase_enum))
-               {
-                 bfd_vma maxpage = result.value;
+             bfd_vma maxpage = lhs.value;
+             bfd_vma commonpage = expld.result.value;
 
-                 result.value = align_n (dot, maxpage);
-                 if (exp_data_seg.phase != exp_dataseg_adjust)
+             expld.result.value = align_n (expld.dot, maxpage);
+             if (expld.dataseg.phase == exp_dataseg_relro_adjust)
+               expld.result.value = expld.dataseg.base;
+             else if (expld.dataseg.phase == exp_dataseg_adjust)
+               {
+                 if (commonpage < maxpage)
+                   expld.result.value += ((expld.dot + commonpage - 1)
+                                          & (maxpage - commonpage));
+               }
+             else
+               {
+                 expld.result.value += expld.dot & (maxpage - 1);
+                 if (expld.dataseg.phase == exp_dataseg_done)
+                   {
+                     /* OK.  */
+                   }
+                 else if (expld.dataseg.phase == exp_dataseg_none)
                    {
-                     result.value += dot & (maxpage - 1);
-                     if (allocation_done == lang_allocating_phase_enum)
-                       {
-                         exp_data_seg.phase = exp_dataseg_align_seen;
-                         exp_data_seg.base = result.value;
-                         exp_data_seg.pagesize = other.value;
-                       }
+                     expld.dataseg.phase = exp_dataseg_align_seen;
+                     expld.dataseg.min_base = expld.dot;
+                     expld.dataseg.base = expld.result.value;
+                     expld.dataseg.pagesize = commonpage;
+                     expld.dataseg.maxpagesize = maxpage;
+                     expld.dataseg.relro_end = 0;
                    }
-                 else if (other.value < maxpage)
-                   result.value += (dot + other.value - 1)
-                                   & (maxpage - other.value);
+                 else
+                   expld.result.valid_p = FALSE;
+               }
+           }
+         break;
+
+       case DATA_SEGMENT_RELRO_END:
+         expld.dataseg.relro = exp_dataseg_relro_end;
+         if (expld.phase == lang_first_phase_enum
+             || expld.section != bfd_abs_section_ptr)
+           expld.result.valid_p = FALSE;
+         else if (expld.dataseg.phase == exp_dataseg_align_seen
+                  || expld.dataseg.phase == exp_dataseg_adjust
+                  || expld.dataseg.phase == exp_dataseg_relro_adjust
+                  || expld.dataseg.phase == exp_dataseg_done)
+           {
+             if (expld.dataseg.phase == exp_dataseg_align_seen
+                 || expld.dataseg.phase == exp_dataseg_relro_adjust)
+               expld.dataseg.relro_end = lhs.value + expld.result.value;
+
+             if (expld.dataseg.phase == exp_dataseg_relro_adjust
+                 && (expld.dataseg.relro_end
+                     & (expld.dataseg.pagesize - 1)))
+               {
+                 expld.dataseg.relro_end += expld.dataseg.pagesize - 1;
+                 expld.dataseg.relro_end &= ~(expld.dataseg.pagesize - 1);
+                 expld.result.value = (expld.dataseg.relro_end
+                                       - expld.result.value);
                }
              else
-               result.valid_p = false;
-             break;
+               expld.result.value = lhs.value;
 
-           default:
-             FAIL ();
+             if (expld.dataseg.phase == exp_dataseg_align_seen)
+               expld.dataseg.phase = exp_dataseg_relro_seen;
            }
-       }
-      else
-       {
-         result.valid_p = false;
+         else
+           expld.result.valid_p = FALSE;
+         break;
+
+       default:
+         FAIL ();
        }
     }
-
-  return result;
-}
-
-static etree_value_type
-fold_trinary (tree, current_section, allocation_done, dot, dotp)
-     etree_type *tree;
-     lang_output_section_statement_type *current_section;
-     lang_phase_type allocation_done;
-     bfd_vma dot;
-     bfd_vma *dotp;
-{
-  etree_value_type result;
-
-  result = exp_fold_tree (tree->trinary.cond, current_section,
-                         allocation_done, dot, dotp);
-  if (result.valid_p)
-    result = exp_fold_tree ((result.value
-                            ? tree->trinary.lhs
-                            : tree->trinary.rhs),
-                           current_section,
-                           allocation_done, dot, dotp);
-
-  return result;
 }
 
-etree_value_type
-invalid ()
+static void
+fold_trinary (etree_type *tree)
 {
-  etree_value_type new;
-  new.valid_p = false;
-  return new;
+  exp_fold_tree_1 (tree->trinary.cond);
+  if (expld.result.valid_p)
+    exp_fold_tree_1 (expld.result.value
+                    ? tree->trinary.lhs
+                    : tree->trinary.rhs);
 }
 
-static etree_value_type
-fold_name (tree, current_section, allocation_done, dot)
-     etree_type *tree;
-     lang_output_section_statement_type *current_section;
-     lang_phase_type allocation_done;
-     bfd_vma dot;
+static void
+fold_name (etree_type *tree)
 {
-  etree_value_type result;
+  memset (&expld.result, 0, sizeof (expld.result));
 
   switch (tree->type.node_code)
     {
     case SIZEOF_HEADERS:
-      if (allocation_done != lang_first_phase_enum)
+      if (expld.phase != lang_first_phase_enum)
        {
-         result = new_abs ((bfd_vma)
-                           bfd_sizeof_headers (output_bfd,
-                                               link_info.relocateable));
-       }
-      else
-       {
-         result.valid_p = false;
+         bfd_vma hdr_size = 0;
+         /* Don't find the real header size if only marking sections;
+            The bfd function may cache incorrect data.  */
+         if (expld.phase != lang_mark_phase_enum)
+           hdr_size = bfd_sizeof_headers (link_info.output_bfd, &link_info);
+         new_number (hdr_size);
        }
       break;
+
     case DEFINED:
-      if (allocation_done == lang_first_phase_enum)
-       result.valid_p = false;
-      else
+      if (expld.phase != lang_first_phase_enum)
        {
          struct bfd_link_hash_entry *h;
+         struct definedness_hash_entry *def;
 
-         h = bfd_wrapped_link_hash_lookup (output_bfd, &link_info,
+         h = bfd_wrapped_link_hash_lookup (link_info.output_bfd,
+                                           &link_info,
                                            tree->name.name,
-                                           false, false, true);
-         result.value = (h != (struct bfd_link_hash_entry *) NULL
-                         && (h->type == bfd_link_hash_defined
-                             || h->type == bfd_link_hash_defweak
-                             || h->type == bfd_link_hash_common));
-         result.section = 0;
-         result.valid_p = true;
+                                           FALSE, FALSE, TRUE);
+         new_number (h != NULL
+                     && (h->type == bfd_link_hash_defined
+                         || h->type == bfd_link_hash_defweak
+                         || h->type == bfd_link_hash_common)
+                     && ((def = symbol_defined (tree->name.name)) == NULL
+                         || def->by_object
+                         || def->iteration == (lang_statement_iteration & 1)));
        }
       break;
+
     case NAME:
-      result.valid_p = false;
-      if (tree->name.name[0] == '.' && tree->name.name[1] == 0)
+      if (expld.assign_name != NULL
+         && strcmp (expld.assign_name, tree->name.name) == 0)
        {
-         if (allocation_done != lang_first_phase_enum)
-           result = new_rel_from_section (dot, current_section);
-         else
-           result = invalid ();
+         /* Self-assignment is only allowed for absolute symbols
+            defined in a linker script.  */
+         struct bfd_link_hash_entry *h;
+         struct definedness_hash_entry *def;
+
+         h = bfd_wrapped_link_hash_lookup (link_info.output_bfd,
+                                           &link_info,
+                                           tree->name.name,
+                                           FALSE, FALSE, TRUE);
+         if (!(h != NULL
+               && (h->type == bfd_link_hash_defined
+                   || h->type == bfd_link_hash_defweak)
+               && h->u.def.section == bfd_abs_section_ptr
+               && (def = symbol_defined (tree->name.name)) != NULL
+               && def->iteration == (lang_statement_iteration & 1)))
+           expld.assign_name = NULL;
        }
-      else if (allocation_done != lang_first_phase_enum)
+      if (expld.phase == lang_first_phase_enum)
+       ;
+      else if (tree->name.name[0] == '.' && tree->name.name[1] == 0)
+       new_rel_from_abs (expld.dot);
+      else
        {
          struct bfd_link_hash_entry *h;
 
-         h = bfd_wrapped_link_hash_lookup (output_bfd, &link_info,
+         h = bfd_wrapped_link_hash_lookup (link_info.output_bfd,
+                                           &link_info,
                                            tree->name.name,
-                                           false, false, true);
-         if (h != NULL
-             && (h->type == bfd_link_hash_defined
-                 || h->type == bfd_link_hash_defweak))
+                                           TRUE, FALSE, TRUE);
+         if (!h)
+           einfo (_("%P%F: bfd_link_hash_lookup failed: %E\n"));
+         else if (h->type == bfd_link_hash_defined
+                  || h->type == bfd_link_hash_defweak)
            {
-             if (bfd_is_abs_section (h->u.def.section))
-               result = new_abs (h->u.def.value);
-             else if (allocation_done == lang_final_phase_enum
-                      || allocation_done == lang_allocating_phase_enum)
-               {
-                 asection *output_section;
+             asection *output_section;
 
-                 output_section = h->u.def.section->output_section;
-                 if (output_section == NULL)
-                   einfo (_("%X%S: unresolvable symbol `%s' referenced in expression\n"),
-                          tree->name.name);
+             output_section = h->u.def.section->output_section;
+             if (output_section == NULL)
+               {
+                 if (expld.phase == lang_mark_phase_enum)
+                   new_rel (h->u.def.value, h->u.def.section);
                  else
-                   {
-                     lang_output_section_statement_type *os;
-
-                     os = (lang_output_section_statement_lookup
-                           (bfd_get_section_name (output_bfd,
-                                                  output_section)));
-
-                     /* FIXME: Is this correct if this section is
-                        being linked with -R?  */
-                     result = new_rel ((h->u.def.value
-                                        + h->u.def.section->output_offset),
-                                       NULL,
-                                       os);
-                   }
+                   einfo (_("%X%S: unresolvable symbol `%s'"
+                            " referenced in expression\n"),
+                          tree, tree->name.name);
                }
+             else if (output_section == bfd_abs_section_ptr
+                      && (expld.section != bfd_abs_section_ptr
+                          || config.sane_expr))
+               new_number (h->u.def.value + h->u.def.section->output_offset);
+             else
+               new_rel (h->u.def.value + h->u.def.section->output_offset,
+                        output_section);
+           }
+         else if (expld.phase == lang_final_phase_enum
+                  || (expld.phase != lang_mark_phase_enum
+                      && expld.assigning_to_dot))
+           einfo (_("%F%S: undefined symbol `%s'"
+                    " referenced in expression\n"),
+                  tree, tree->name.name);
+         else if (h->type == bfd_link_hash_new)
+           {
+             h->type = bfd_link_hash_undefined;
+             h->u.undef.abfd = NULL;
+             if (h->u.undef.next == NULL && h != link_info.hash->undefs_tail)
+               bfd_link_add_undef (link_info.hash, h);
            }
-         else if (allocation_done == lang_final_phase_enum)
-           einfo (_("%F%S: undefined symbol `%s' referenced in expression\n"),
-                  tree->name.name);
        }
       break;
 
     case ADDR:
-      if (allocation_done != lang_first_phase_enum)
+      if (expld.phase != lang_first_phase_enum)
        {
          lang_output_section_statement_type *os;
 
          os = lang_output_section_find (tree->name.name);
-         check (os, tree->name.name, "ADDR");
-         result = new_rel (0, NULL, os);
+         if (os == NULL)
+           {
+             if (expld.phase == lang_final_phase_enum)
+               einfo (_("%F%S: undefined section `%s'"
+                        " referenced in expression\n"),
+                      tree, tree->name.name);
+           }
+         else if (os->processed_vma)
+           new_rel (0, os->bfd_section);
        }
-      else
-       result = invalid ();
       break;
 
     case LOADADDR:
-      if (allocation_done != lang_first_phase_enum)
+      if (expld.phase != lang_first_phase_enum)
        {
          lang_output_section_statement_type *os;
 
          os = lang_output_section_find (tree->name.name);
-         check (os, tree->name.name, "LOADADDR");
-         if (os->load_base == NULL)
-           result = new_rel (0, NULL, os);
-         else
-           result = exp_fold_tree_no_dot (os->load_base,
-                                          abs_output_section,
-                                          allocation_done);
+         if (os == NULL)
+           {
+             if (expld.phase == lang_final_phase_enum)
+               einfo (_("%F%S: undefined section `%s'"
+                        " referenced in expression\n"),
+                      tree, tree->name.name);
+           }
+         else if (os->processed_lma)
+           {
+             if (os->load_base == NULL)
+               new_abs (os->bfd_section->lma);
+             else
+               {
+                 exp_fold_tree_1 (os->load_base);
+                 if (expld.result.valid_p)
+                   make_abs ();
+               }
+           }
        }
-      else
-       result = invalid ();
       break;
 
     case SIZEOF:
-      if (allocation_done != lang_first_phase_enum)
+    case ALIGNOF:
+      if (expld.phase != lang_first_phase_enum)
        {
-         int opb = bfd_octets_per_byte (output_bfd);
          lang_output_section_statement_type *os;
 
          os = lang_output_section_find (tree->name.name);
-         check (os, tree->name.name, "SIZEOF");
-         result = new_abs (os->bfd_section->_raw_size / opb);
+         if (os == NULL)
+           {
+             if (expld.phase == lang_final_phase_enum)
+               einfo (_("%F%S: undefined section `%s'"
+                        " referenced in expression\n"),
+                      tree, tree->name.name);
+             new_number (0);
+           }
+         else if (os->bfd_section != NULL)
+           {
+             bfd_vma val;
+
+             if (tree->type.node_code == SIZEOF)
+               val = (os->bfd_section->size
+                      / bfd_octets_per_byte (link_info.output_bfd));
+             else
+               val = (bfd_vma)1 << os->bfd_section->alignment_power;
+
+             new_number (val);
+           }
+         else
+           new_number (0);
        }
+      break;
+
+    case LENGTH:
+      {
+        lang_memory_region_type *mem;
+
+        mem = lang_memory_region_lookup (tree->name.name, FALSE);
+        if (mem != NULL)
+          new_number (mem->length);
+        else
+          einfo (_("%F%S: undefined MEMORY region `%s'"
+                  " referenced in expression\n"),
+                tree, tree->name.name);
+      }
+      break;
+
+    case ORIGIN:
+      if (expld.phase != lang_first_phase_enum)
+       {
+         lang_memory_region_type *mem;
+
+         mem = lang_memory_region_lookup (tree->name.name, FALSE);
+         if (mem != NULL)
+           new_rel_from_abs (mem->origin);
+         else
+           einfo (_("%F%S: undefined MEMORY region `%s'"
+                    " referenced in expression\n"),
+                  tree, tree->name.name);
+       }
+      break;
+
+    case CONSTANT:
+      if (strcmp (tree->name.name, "MAXPAGESIZE") == 0)
+       new_number (config.maxpagesize);
+      else if (strcmp (tree->name.name, "COMMONPAGESIZE") == 0)
+       new_number (config.commonpagesize);
       else
-       result = invalid ();
+       einfo (_("%F%S: unknown constant `%s' referenced in expression\n"),
+              tree, tree->name.name);
       break;
 
     default:
       FAIL ();
       break;
     }
+}
+
+/* Return true if TREE is '.'.  */
+static bfd_boolean
+is_dot (const etree_type *tree)
+{
+  return (tree->type.node_class == etree_name
+         && tree->type.node_code == NAME
+         && tree->name.name[0] == '.'
+         && tree->name.name[1] == 0);
+}
+
+/* Return true if TREE is a constant equal to VAL.  */
+
+static bfd_boolean
+is_value (const etree_type *tree, bfd_vma val)
+{
+  return (tree->type.node_class == etree_value
+         && tree->value.value == val);
+}
+
+/* Return true if TREE is an absolute symbol equal to VAL defined in
+   a linker script.  */
+
+static bfd_boolean
+is_sym_value (const etree_type *tree, bfd_vma val)
+{
+  struct bfd_link_hash_entry *h;
+  struct definedness_hash_entry *def;
+
+  return (tree->type.node_class == etree_name
+         && tree->type.node_code == NAME
+         && (def = symbol_defined (tree->name.name)) != NULL
+         && def->by_script
+         && def->iteration == (lang_statement_iteration & 1)
+         && (h = bfd_wrapped_link_hash_lookup (link_info.output_bfd,
+                                               &link_info,
+                                               tree->name.name,
+                                               FALSE, FALSE, TRUE)) != NULL
+         && h->type == bfd_link_hash_defined
+         && h->u.def.section == bfd_abs_section_ptr
+         && h->u.def.value == val);
+}
+
+/* Return true if TREE is ". != 0".  */
+
+static bfd_boolean
+is_dot_ne_0 (const etree_type *tree)
+{
+  return (tree->type.node_class == etree_binary
+         && tree->type.node_code == NE
+         && is_dot (tree->binary.lhs)
+         && is_value (tree->binary.rhs, 0));
+}
 
-  return result;
+/* Return true if TREE is ". = . + 0" or ". = . + sym" where sym is an
+   absolute constant with value 0 defined in a linker script.  */
+
+static bfd_boolean
+is_dot_plus_0 (const etree_type *tree)
+{
+  return (tree->type.node_class == etree_binary
+         && tree->type.node_code == '+'
+         && is_dot (tree->binary.lhs)
+         && (is_value (tree->binary.rhs, 0)
+             || is_sym_value (tree->binary.rhs, 0)));
 }
 
-etree_value_type
-exp_fold_tree (tree, current_section, allocation_done, dot, dotp)
-     etree_type *tree;
-     lang_output_section_statement_type *current_section;
-     lang_phase_type allocation_done;
-     bfd_vma dot;
-     bfd_vma *dotp;
+/* Return true if TREE is "ALIGN (. != 0 ? some_expression : 1)".  */
+
+static bfd_boolean
+is_align_conditional (const etree_type *tree)
 {
-  etree_value_type result;
+  if (tree->type.node_class == etree_unary
+      && tree->type.node_code == ALIGN_K)
+    {
+      tree = tree->unary.child;
+      return (tree->type.node_class == etree_trinary
+             && is_dot_ne_0 (tree->trinary.cond)
+             && is_value (tree->trinary.rhs, 1));
+    }
+  return 0;
+}
 
+static void
+exp_fold_tree_1 (etree_type *tree)
+{
   if (tree == NULL)
     {
-      result.valid_p = false;
-      return result;
+      memset (&expld.result, 0, sizeof (expld.result));
+      return;
     }
 
   switch (tree->type.node_class)
     {
     case etree_value:
-      result = new_rel (tree->value.value, tree->value.str, current_section);
+      if (expld.section == bfd_abs_section_ptr
+         && !config.sane_expr)
+       new_abs (tree->value.value);
+      else
+       new_number (tree->value.value);
+      expld.result.str = tree->value.str;
       break;
 
     case etree_rel:
-      if (allocation_done != lang_final_phase_enum)
-       result.valid_p = false;
+      if (expld.phase != lang_first_phase_enum)
+       {
+         asection *output_section = tree->rel.section->output_section;
+         new_rel (tree->rel.value + tree->rel.section->output_offset,
+                  output_section);
+       }
       else
-       result = new_rel ((tree->rel.value
-                          + tree->rel.section->output_section->vma
-                          + tree->rel.section->output_offset),
-                         NULL,
-                         current_section);
+       memset (&expld.result, 0, sizeof (expld.result));
       break;
 
     case etree_assert:
-      result = exp_fold_tree (tree->assert_s.child,
-                             current_section,
-                             allocation_done, dot, dotp);
-      if (result.valid_p)
-       {
-         if (! result.value)
-           einfo ("%F%P: %s\n", tree->assert_s.message);
-         return result;
-       }
+      exp_fold_tree_1 (tree->assert_s.child);
+      if (expld.phase == lang_final_phase_enum && !expld.result.value)
+       einfo ("%X%P: %s\n", tree->assert_s.message);
       break;
 
     case etree_unary:
-      result = fold_unary (tree, current_section, allocation_done,
-                          dot, dotp);
+      fold_unary (tree);
       break;
 
     case etree_binary:
-      result = fold_binary (tree, current_section, allocation_done,
-                           dot, dotp);
+      fold_binary (tree);
       break;
 
     case etree_trinary:
-      result = fold_trinary (tree, current_section, allocation_done,
-                            dot, dotp);
+      fold_trinary (tree);
       break;
 
     case etree_assign:
@@ -721,249 +1008,328 @@ exp_fold_tree (tree, current_section, allocation_done, dot, dotp)
     case etree_provided:
       if (tree->assign.dst[0] == '.' && tree->assign.dst[1] == 0)
        {
-         /* Assignment to dot can only be done during allocation.  */
          if (tree->type.node_class != etree_assign)
-           einfo (_("%F%S can not PROVIDE assignment to location counter\n"));
-         if (allocation_done == lang_allocating_phase_enum
-             || (allocation_done == lang_final_phase_enum
-                 && current_section == abs_output_section))
+           einfo (_("%F%S can not PROVIDE assignment to"
+                    " location counter\n"), tree);
+         if (expld.phase != lang_first_phase_enum)
            {
-             result = exp_fold_tree (tree->assign.src,
-                                     current_section,
-                                     allocation_done, dot,
-                                     dotp);
-             if (! result.valid_p)
-               einfo (_("%F%S invalid assignment to location counter\n"));
-             else
+             /* Notify the folder that this is an assignment to dot.  */
+             expld.assigning_to_dot = TRUE;
+             exp_fold_tree_1 (tree->assign.src);
+             expld.assigning_to_dot = FALSE;
+
+             /* If we are assigning to dot inside an output section
+                arrange to keep the section, except for certain
+                expressions that evaluate to zero.  We ignore . = 0,
+                . = . + 0, and . = ALIGN (. != 0 ? expr : 1).  */
+             if (expld.phase == lang_mark_phase_enum
+                 && expld.section != bfd_abs_section_ptr
+                 && !(expld.result.valid_p
+                      && expld.result.value == 0
+                      && (is_value (tree->assign.src, 0)
+                          || is_sym_value (tree->assign.src, 0)
+                          || is_dot_plus_0 (tree->assign.src)
+                          || is_align_conditional (tree->assign.src))))
+               expld.section->flags |= SEC_KEEP;
+
+             if (!expld.result.valid_p)
+               {
+                 if (expld.phase != lang_mark_phase_enum)
+                   einfo (_("%F%S invalid assignment to"
+                            " location counter\n"), tree);
+               }
+             else if (expld.dotp == NULL)
+               einfo (_("%F%S assignment to location counter"
+                        " invalid outside of SECTIONS\n"), tree);
+
+             /* After allocation, assignment to dot should not be
+                done inside an output section since allocation adds a
+                padding statement that effectively duplicates the
+                assignment.  */
+             else if (expld.phase <= lang_allocating_phase_enum
+                      || expld.section == bfd_abs_section_ptr)
                {
-                 if (current_section == NULL)
-                   einfo (_("%F%S assignment to location counter invalid outside of SECTION\n"));
+                 bfd_vma nextdot;
+
+                 nextdot = expld.result.value;
+                 if (expld.result.section != NULL)
+                   nextdot += expld.result.section->vma;
+                 else
+                   nextdot += expld.section->vma;
+                 if (nextdot < expld.dot
+                     && expld.section != bfd_abs_section_ptr)
+                   einfo (_("%F%S cannot move location counter backwards"
+                            " (from %V to %V)\n"),
+                          tree, expld.dot, nextdot);
                  else
                    {
-                     bfd_vma nextdot;
-
-                     nextdot = (result.value
-                                + current_section->bfd_section->vma);
-                     if (nextdot < dot
-                         && current_section != abs_output_section)
-                       einfo (_("%F%S cannot move location counter backwards (from %V to %V)\n"),
-                              dot, nextdot);
-                     else
-                       *dotp = nextdot;
+                     expld.dot = nextdot;
+                     *expld.dotp = nextdot;
                    }
                }
            }
+         else
+           memset (&expld.result, 0, sizeof (expld.result));
        }
       else
        {
-         result = exp_fold_tree (tree->assign.src,
-                                 current_section, allocation_done,
-                                 dot, dotp);
-         if (result.valid_p)
-           {
-             boolean create;
-             struct bfd_link_hash_entry *h;
+         struct bfd_link_hash_entry *h = NULL;
 
-             if (tree->type.node_class == etree_assign)
-               create = true;
-             else
-               create = false;
+         if (tree->type.node_class == etree_provide)
+           {
              h = bfd_link_hash_lookup (link_info.hash, tree->assign.dst,
-                                       create, false, false);
-             if (h == (struct bfd_link_hash_entry *) NULL)
+                                       FALSE, FALSE, TRUE);
+             if (h == NULL
+                 || !(h->type == bfd_link_hash_new
+                      || h->type == bfd_link_hash_undefined
+                      || h->linker_def))
                {
-                 if (tree->type.node_class == etree_assign)
+                 /* Do nothing.  The symbol was never referenced, or
+                    was defined in some object file.  Undefined weak
+                    symbols stay undefined.  */
+                 break;
+               }
+           }
+
+         expld.assign_name = tree->assign.dst;
+         exp_fold_tree_1 (tree->assign.src);
+         /* expld.assign_name remaining equal to tree->assign.dst
+            below indicates the evaluation of tree->assign.src did
+            not use the value of tree->assign.dst.  We don't allow
+            self assignment until the final phase for two reasons:
+            1) Expressions are evaluated multiple times.  With
+            relaxation, the number of times may vary.
+            2) Section relative symbol values cannot be correctly
+            converted to absolute values, as is required by many
+            expressions, until final section sizing is complete.  */
+         if ((expld.result.valid_p
+              && (expld.phase == lang_final_phase_enum
+                  || expld.assign_name != NULL))
+             || (expld.phase <= lang_mark_phase_enum
+                 && tree->type.node_class == etree_assign
+                 && tree->assign.defsym))
+           {
+             if (h == NULL)
+               {
+                 h = bfd_link_hash_lookup (link_info.hash, tree->assign.dst,
+                                           TRUE, FALSE, TRUE);
+                 if (h == NULL)
                    einfo (_("%P%F:%s: hash creation failed\n"),
                           tree->assign.dst);
                }
-             else if (tree->type.node_class == etree_provide
-                      && h->type != bfd_link_hash_undefined
-                      && h->type != bfd_link_hash_common)
+
+             if (expld.result.section == NULL)
+               expld.result.section = expld.section;
+             if (!update_definedness (tree->assign.dst, h) && 0)
                {
-                 /* Do nothing.  The symbol was defined by some
-                    object.  */
+                 /* Symbol was already defined.  For now this error
+                    is disabled because it causes failures in the ld
+                    testsuite: ld-elf/var1, ld-scripts/defined5, and
+                    ld-scripts/pr14962.  Some of these no doubt
+                    reflect scripts used in the wild.  */
+                 (*link_info.callbacks->multiple_definition)
+                   (&link_info, h, link_info.output_bfd,
+                    expld.result.section, expld.result.value);
                }
-             else
+             h->type = bfd_link_hash_defined;
+             h->u.def.value = expld.result.value;
+             h->u.def.section = expld.result.section;
+             if (tree->type.node_class == etree_provide)
+               tree->type.node_class = etree_provided;
+
+             /* Copy the symbol type if this is a simple assignment of
+                one symbol to another.  This could be more general
+                (e.g. a ?: operator with NAMEs in each branch).  */
+             if (tree->assign.src->type.node_class == etree_name)
                {
-                 /* FIXME: Should we worry if the symbol is already
-                    defined?  */
-                 h->type = bfd_link_hash_defined;
-                 h->u.def.value = result.value;
-                 h->u.def.section = result.section->bfd_section;
-                 if (tree->type.node_class == etree_provide)
-                   tree->type.node_class = etree_provided;
+                 struct bfd_link_hash_entry *hsrc;
+
+                 hsrc = bfd_link_hash_lookup (link_info.hash,
+                                              tree->assign.src->name.name,
+                                              FALSE, FALSE, TRUE);
+                 if (hsrc)
+                   bfd_copy_link_hash_symbol_type (link_info.output_bfd, h,
+                                                   hsrc);
                }
            }
+         else if (expld.phase == lang_final_phase_enum)
+           {
+             h = bfd_link_hash_lookup (link_info.hash, tree->assign.dst,
+                                       FALSE, FALSE, TRUE);
+             if (h != NULL
+                 && h->type == bfd_link_hash_new)
+               h->type = bfd_link_hash_undefined;
+           }
+         expld.assign_name = NULL;
        }
       break;
 
     case etree_name:
-      result = fold_name (tree, current_section, allocation_done, dot);
+      fold_name (tree);
       break;
 
     default:
       FAIL ();
+      memset (&expld.result, 0, sizeof (expld.result));
       break;
     }
+}
 
-  return result;
+void
+exp_fold_tree (etree_type *tree, asection *current_section, bfd_vma *dotp)
+{
+  expld.dot = *dotp;
+  expld.dotp = dotp;
+  expld.section = current_section;
+  exp_fold_tree_1 (tree);
 }
 
-static etree_value_type
-exp_fold_tree_no_dot (tree, current_section, allocation_done)
-     etree_type *tree;
-     lang_output_section_statement_type *current_section;
-     lang_phase_type allocation_done;
+void
+exp_fold_tree_no_dot (etree_type *tree)
 {
-  return exp_fold_tree (tree, current_section, allocation_done,
-                       (bfd_vma) 0, (bfd_vma *) NULL);
+  expld.dot = 0;
+  expld.dotp = NULL;
+  expld.section = bfd_abs_section_ptr;
+  exp_fold_tree_1 (tree);
 }
 
 etree_type *
-exp_binop (code, lhs, rhs)
-     int code;
-     etree_type *lhs;
-     etree_type *rhs;
+exp_binop (int code, etree_type *lhs, etree_type *rhs)
 {
-  etree_type value, *new;
-  etree_value_type r;
+  etree_type value, *new_e;
 
   value.type.node_code = code;
+  value.type.filename = lhs->type.filename;
+  value.type.lineno = lhs->type.lineno;
   value.binary.lhs = lhs;
   value.binary.rhs = rhs;
   value.type.node_class = etree_binary;
-  r = exp_fold_tree_no_dot (&value,
-                           abs_output_section,
-                           lang_first_phase_enum);
-  if (r.valid_p)
-    {
-      return exp_intop (r.value);
-    }
-  new = (etree_type *) stat_alloc (sizeof (new->binary));
-  memcpy ((char *) new, (char *) &value, sizeof (new->binary));
-  return new;
+  exp_fold_tree_no_dot (&value);
+  if (expld.result.valid_p)
+    return exp_intop (expld.result.value);
+
+  new_e = (etree_type *) stat_alloc (sizeof (new_e->binary));
+  memcpy (new_e, &value, sizeof (new_e->binary));
+  return new_e;
 }
 
 etree_type *
-exp_trinop (code, cond, lhs, rhs)
-     int code;
-     etree_type *cond;
-     etree_type *lhs;
-     etree_type *rhs;
+exp_trinop (int code, etree_type *cond, etree_type *lhs, etree_type *rhs)
 {
-  etree_type value, *new;
-  etree_value_type r;
+  etree_type value, *new_e;
+
   value.type.node_code = code;
+  value.type.filename = cond->type.filename;
+  value.type.lineno = cond->type.lineno;
   value.trinary.lhs = lhs;
   value.trinary.cond = cond;
   value.trinary.rhs = rhs;
   value.type.node_class = etree_trinary;
-  r = exp_fold_tree_no_dot (&value,
-                           (lang_output_section_statement_type *) NULL,
-                           lang_first_phase_enum);
-  if (r.valid_p)
-    return exp_intop (r.value);
-
-  new = (etree_type *) stat_alloc (sizeof (new->trinary));
-  memcpy ((char *) new, (char *) &value, sizeof (new->trinary));
-  return new;
+  exp_fold_tree_no_dot (&value);
+  if (expld.result.valid_p)
+    return exp_intop (expld.result.value);
+
+  new_e = (etree_type *) stat_alloc (sizeof (new_e->trinary));
+  memcpy (new_e, &value, sizeof (new_e->trinary));
+  return new_e;
 }
 
 etree_type *
-exp_unop (code, child)
-     int code;
-     etree_type *child;
+exp_unop (int code, etree_type *child)
 {
-  etree_type value, *new;
+  etree_type value, *new_e;
 
-  etree_value_type r;
   value.unary.type.node_code = code;
+  value.unary.type.filename = child->type.filename;
+  value.unary.type.lineno = child->type.lineno;
   value.unary.child = child;
   value.unary.type.node_class = etree_unary;
-  r = exp_fold_tree_no_dot (&value, abs_output_section,
-                           lang_first_phase_enum);
-  if (r.valid_p)
-    return exp_intop (r.value);
-
-  new = (etree_type *) stat_alloc (sizeof (new->unary));
-  memcpy ((char *) new, (char *) &value, sizeof (new->unary));
-  return new;
+  exp_fold_tree_no_dot (&value);
+  if (expld.result.valid_p)
+    return exp_intop (expld.result.value);
+
+  new_e = (etree_type *) stat_alloc (sizeof (new_e->unary));
+  memcpy (new_e, &value, sizeof (new_e->unary));
+  return new_e;
 }
 
 etree_type *
-exp_nameop (code, name)
-     int code;
-     const char *name;
+exp_nameop (int code, const char *name)
 {
-  etree_type value, *new;
-  etree_value_type r;
+  etree_type value, *new_e;
+
   value.name.type.node_code = code;
+  value.name.type.filename = ldlex_filename ();
+  value.name.type.lineno = lineno;
   value.name.name = name;
   value.name.type.node_class = etree_name;
 
-  r = exp_fold_tree_no_dot (&value,
-                           (lang_output_section_statement_type *) NULL,
-                           lang_first_phase_enum);
-  if (r.valid_p)
-    return exp_intop (r.value);
+  exp_fold_tree_no_dot (&value);
+  if (expld.result.valid_p)
+    return exp_intop (expld.result.value);
 
-  new = (etree_type *) stat_alloc (sizeof (new->name));
-  memcpy ((char *) new, (char *) &value, sizeof (new->name));
-  return new;
+  new_e = (etree_type *) stat_alloc (sizeof (new_e->name));
+  memcpy (new_e, &value, sizeof (new_e->name));
+  return new_e;
 
 }
 
-etree_type *
-exp_assop (code, dst, src)
-     int code;
-     const char *dst;
-     etree_type *src;
+static etree_type *
+exp_assop (const char *dst,
+          etree_type *src,
+          enum node_tree_enum class,
+          bfd_boolean defsym,
+          bfd_boolean hidden)
 {
-  etree_type value, *new;
+  etree_type *n;
+
+  n = (etree_type *) stat_alloc (sizeof (n->assign));
+  n->assign.type.node_code = '=';
+  n->assign.type.filename = src->type.filename;
+  n->assign.type.lineno = src->type.lineno;
+  n->assign.type.node_class = class;
+  n->assign.src = src;
+  n->assign.dst = dst;
+  n->assign.defsym = defsym;
+  n->assign.hidden = hidden;
+  return n;
+}
 
-  value.assign.type.node_code = code;
+/* Handle linker script assignments and HIDDEN.  */
 
-  value.assign.src = src;
-  value.assign.dst = dst;
-  value.assign.type.node_class = etree_assign;
+etree_type *
+exp_assign (const char *dst, etree_type *src, bfd_boolean hidden)
+{
+  return exp_assop (dst, src, etree_assign, FALSE, hidden);
+}
 
-#if 0
-  if (exp_fold_tree_no_dot (&value, &result))
-    return exp_intop (result);
-#endif
-  new = (etree_type *) stat_alloc (sizeof (new->assign));
-  memcpy ((char *) new, (char *) &value, sizeof (new->assign));
-  return new;
+/* Handle --defsym command-line option.  */
+
+etree_type *
+exp_defsym (const char *dst, etree_type *src)
+{
+  return exp_assop (dst, src, etree_assign, TRUE, FALSE);
 }
 
 /* Handle PROVIDE.  */
 
 etree_type *
-exp_provide (dst, src)
-     const char *dst;
-     etree_type *src;
+exp_provide (const char *dst, etree_type *src, bfd_boolean hidden)
 {
-  etree_type *n;
-
-  n = (etree_type *) stat_alloc (sizeof (n->assign));
-  n->assign.type.node_code = '=';
-  n->assign.type.node_class = etree_provide;
-  n->assign.src = src;
-  n->assign.dst = dst;
-  return n;
+  return exp_assop (dst, src, etree_provide, FALSE, hidden);
 }
 
 /* Handle ASSERT.  */
 
 etree_type *
-exp_assert (exp, message)
-     etree_type *exp;
-     const char *message;
+exp_assert (etree_type *exp, const char *message)
 {
   etree_type *n;
 
   n = (etree_type *) stat_alloc (sizeof (n->assert_s));
   n->assert_s.type.node_code = '!';
+  n->assert_s.type.filename = exp->type.filename;
+  n->assert_s.type.lineno = exp->type.lineno;
   n->assert_s.type.node_class = etree_assert;
   n->assert_s.child = exp;
   n->assert_s.message = message;
@@ -971,9 +1337,10 @@ exp_assert (exp, message)
 }
 
 void
-exp_print_tree (tree)
-     etree_type *tree;
+exp_print_tree (etree_type *tree)
 {
+  bfd_boolean function_like;
+
   if (config.map_file == NULL)
     config.map_file = stderr;
 
@@ -994,44 +1361,66 @@ exp_print_tree (tree)
       minfo ("%s+0x%v", tree->rel.section->name, tree->rel.value);
       return;
     case etree_assign:
-#if 0
-      if (tree->assign.dst->sdefs != (asymbol *) NULL)
-       fprintf (config.map_file, "%s (%x) ", tree->assign.dst->name,
-                tree->assign.dst->sdefs->value);
-      else
-       fprintf (config.map_file, "%s (UNDEFINED)", tree->assign.dst->name);
-#endif
-      fprintf (config.map_file, "%s", tree->assign.dst);
-      exp_print_token (tree->type.node_code, true);
+      fputs (tree->assign.dst, config.map_file);
+      exp_print_token (tree->type.node_code, TRUE);
       exp_print_tree (tree->assign.src);
       break;
     case etree_provide:
     case etree_provided:
       fprintf (config.map_file, "PROVIDE (%s, ", tree->assign.dst);
       exp_print_tree (tree->assign.src);
-      fprintf (config.map_file, ")");
+      fputc (')', config.map_file);
       break;
     case etree_binary:
-      fprintf (config.map_file, "(");
+      function_like = FALSE;
+      switch (tree->type.node_code)
+       {
+       case MAX_K:
+       case MIN_K:
+       case ALIGN_K:
+       case DATA_SEGMENT_ALIGN:
+       case DATA_SEGMENT_RELRO_END:
+         function_like = TRUE;
+         break;
+       case SEGMENT_START:
+         /* Special handling because arguments are in reverse order and
+            the segment name is quoted.  */
+         exp_print_token (tree->type.node_code, FALSE);
+         fputs (" (\"", config.map_file);
+         exp_print_tree (tree->binary.rhs);
+         fputs ("\", ", config.map_file);
+         exp_print_tree (tree->binary.lhs);
+         fputc (')', config.map_file);
+         return;
+       }
+      if (function_like)
+       {
+         exp_print_token (tree->type.node_code, FALSE);
+         fputc (' ', config.map_file);
+       }
+      fputc ('(', config.map_file);
       exp_print_tree (tree->binary.lhs);
-      exp_print_token (tree->type.node_code, true);
+      if (function_like)
+       fprintf (config.map_file, ", ");
+      else
+       exp_print_token (tree->type.node_code, TRUE);
       exp_print_tree (tree->binary.rhs);
-      fprintf (config.map_file, ")");
+      fputc (')', config.map_file);
       break;
     case etree_trinary:
       exp_print_tree (tree->trinary.cond);
-      fprintf (config.map_file, "?");
+      fputc ('?', config.map_file);
       exp_print_tree (tree->trinary.lhs);
-      fprintf (config.map_file, ":");
+      fputc (':', config.map_file);
       exp_print_tree (tree->trinary.rhs);
       break;
     case etree_unary:
-      exp_print_token (tree->unary.type.node_code, false);
+      exp_print_token (tree->unary.type.node_code, FALSE);
       if (tree->unary.child)
        {
          fprintf (config.map_file, " (");
          exp_print_tree (tree->unary.child);
-         fprintf (config.map_file, ")");
+         fputc (')', config.map_file);
        }
       break;
 
@@ -1041,17 +1430,12 @@ exp_print_tree (tree)
       fprintf (config.map_file, ", %s)", tree->assert_s.message);
       break;
 
-    case etree_undef:
-      fprintf (config.map_file, "????????");
-      break;
     case etree_name:
       if (tree->type.node_code == NAME)
-       {
-         fprintf (config.map_file, "%s", tree->name.name);
-       }
+       fputs (tree->name.name, config.map_file);
       else
        {
-         exp_print_token (tree->type.node_code, false);
+         exp_print_token (tree->type.node_code, FALSE);
          if (tree->name.name)
            fprintf (config.map_file, " (%s)", tree->name.name);
        }
@@ -1063,62 +1447,53 @@ exp_print_tree (tree)
 }
 
 bfd_vma
-exp_get_vma (tree, def, name, allocation_done)
-     etree_type *tree;
-     bfd_vma def;
-     char *name;
-     lang_phase_type allocation_done;
+exp_get_vma (etree_type *tree, bfd_vma def, char *name)
 {
-  etree_value_type r;
-
   if (tree != NULL)
     {
-      r = exp_fold_tree_no_dot (tree, abs_output_section, allocation_done);
-      if (! r.valid_p && name != NULL)
-       einfo (_("%F%S nonconstant expression for %s\n"), name);
-      return r.value;
+      exp_fold_tree_no_dot (tree);
+      if (expld.result.valid_p)
+       return expld.result.value;
+      else if (name != NULL && expld.phase != lang_mark_phase_enum)
+       einfo (_("%F%S: nonconstant expression for %s\n"),
+              tree, name);
     }
-  else
-    return def;
+  return def;
 }
 
 int
-exp_get_value_int (tree, def, name, allocation_done)
-     etree_type *tree;
-     int def;
-     char *name;
-     lang_phase_type allocation_done;
+exp_get_value_int (etree_type *tree, int def, char *name)
 {
-  return (int) exp_get_vma (tree, (bfd_vma) def, name, allocation_done);
+  return exp_get_vma (tree, def, name);
 }
 
 fill_type *
-exp_get_fill (tree, def, name, allocation_done)
-     etree_type *tree;
-     fill_type *def;
-     char *name;
-     lang_phase_type allocation_done;
+exp_get_fill (etree_type *tree, fill_type *def, char *name)
 {
   fill_type *fill;
-  etree_value_type r;
   size_t len;
   unsigned int val;
 
   if (tree == NULL)
     return def;
 
-  r = exp_fold_tree_no_dot (tree, abs_output_section, allocation_done);
-  if (! r.valid_p && name != NULL)
-    einfo (_("%F%S nonconstant expression for %s\n"), name);
+  exp_fold_tree_no_dot (tree);
+  if (!expld.result.valid_p)
+    {
+      if (name != NULL && expld.phase != lang_mark_phase_enum)
+       einfo (_("%F%S: nonconstant expression for %s\n"),
+              tree, name);
+      return def;
+    }
 
-  if (r.str != NULL && (len = strlen (r.str)) != 0)
+  if (expld.result.str != NULL && (len = strlen (expld.result.str)) != 0)
     {
       unsigned char *dst;
       unsigned char *s;
       fill = (fill_type *) xmalloc ((len + 1) / 2 + sizeof (*fill) - 1);
       fill->size = (len + 1) / 2;
       dst = fill->data;
-      s = r.str;
+      s = (unsigned char *) expld.result.str;
       val = 0;
       do
        {
@@ -1141,7 +1516,7 @@ exp_get_fill (tree, def, name, allocation_done)
   else
     {
       fill = (fill_type *) xmalloc (4 + sizeof (*fill) - 1);
-      val = r.value;
+      val = expld.result.value;
       fill->data[0] = (val >> 24) & 0xff;
       fill->data[1] = (val >> 16) & 0xff;
       fill->data[2] = (val >>  8) & 0xff;
@@ -1152,26 +1527,29 @@ exp_get_fill (tree, def, name, allocation_done)
 }
 
 bfd_vma
-exp_get_abs_int (tree, def, name, allocation_done)
-     etree_type *tree;
-     int def ATTRIBUTE_UNUSED;
-     char *name;
-     lang_phase_type allocation_done;
+exp_get_abs_int (etree_type *tree, int def, char *name)
 {
-  etree_value_type res;
-  res = exp_fold_tree_no_dot (tree, abs_output_section, allocation_done);
-
-  if (res.valid_p)
-    res.value += res.section->bfd_section->vma;
-  else
-    einfo (_("%F%S non constant expression for %s\n"), name);
+  if (tree != NULL)
+    {
+      exp_fold_tree_no_dot (tree);
 
-  return res.value;
+      if (expld.result.valid_p)
+       {
+         if (expld.result.section != NULL)
+           expld.result.value += expld.result.section->vma;
+         return expld.result.value;
+       }
+      else if (name != NULL && expld.phase != lang_mark_phase_enum)
+       {
+         einfo (_("%F%S: nonconstant expression for %s\n"),
+                tree, name);
+       }
+    }
+  return def;
 }
 
-bfd_vma align_n (value, align)
-     bfd_vma value;
-     bfd_vma align;
+static bfd_vma
+align_n (bfd_vma value, bfd_vma align)
 {
   if (align <= 1)
     return value;
@@ -1179,3 +1557,21 @@ bfd_vma align_n (value, align)
   value = (value + align - 1) / align;
   return value * align;
 }
+
+void
+ldexp_init (void)
+{
+  /* The value "13" is ad-hoc, somewhat related to the expected number of
+     assignments in a linker script.  */
+  if (!bfd_hash_table_init_n (&definedness_table,
+                             definedness_newfunc,
+                             sizeof (struct definedness_hash_entry),
+                             13))
+    einfo (_("%P%F: can not create hash table: %E\n"));
+}
+
+void
+ldexp_finish (void)
+{
+  bfd_hash_table_free (&definedness_table);
+}
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