/* COFF specific linker code.

   Copyright (C) 1994-2023 Free Software Foundation, Inc.

   Written by Ian Lance Taylor, Cygnus Support.

   This file is part of BFD, the Binary File Descriptor library.

   This program is free software; you can redistribute it and/or modify

   it under the terms of the GNU General Public License as published by

   the Free Software Foundation; either version 3 of the License, or

   (at your option) any later version.

   This program is distributed in the hope that it will be useful,

   but WITHOUT ANY WARRANTY; without even the implied warranty of

   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

   GNU General Public License for more details.

   You should have received a copy of the GNU General Public License

   along with this program; if not, write to the Free Software

   Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston,

   MA 02110-1301, USA.  */

/* This file contains the COFF backend linker code.  */

#include "sysdep.h"

#include "bfd.h"

#include "bfdlink.h"

#include "libbfd.h"

#include "coff/internal.h"

#include "libcoff.h"

#include "safe-ctype.h"

static bool coff_link_add_object_symbols (bfd *, struct bfd_link_info *);

static bool coff_link_check_archive_element

  (bfd *, struct bfd_link_info *, struct bfd_link_hash_entry *, const char *,

   bool *);

static bool coff_link_add_symbols (bfd *, struct bfd_link_info *);

/* Return TRUE if SYM is a weak, external symbol.  */

#define IS_WEAK_EXTERNAL(abfd, sym)     \

  ((sym).n_sclass == C_WEAKEXT        \

   || (obj_pe (abfd) && (sym).n_sclass == C_NT_WEAK))

/* Return TRUE if SYM is an external symbol.  */

#define IS_EXTERNAL(abfd, sym)        \

  ((sym).n_sclass == C_EXT || IS_WEAK_EXTERNAL (abfd, sym))

/* Define macros so that the ISFCN, et. al., macros work correctly.

   These macros are defined in include/coff/internal.h in terms of

   N_TMASK, etc.  These definitions require a user to define local

   variables with the appropriate names, and with values from the

   coff_data (abfd) structure.  */

#define N_TMASK n_tmask

#define N_BTSHFT n_btshft

#define N_BTMASK n_btmask

/* Create an entry in a COFF linker hash table.  */

struct bfd_hash_entry *

_bfd_coff_link_hash_newfunc (struct bfd_hash_entry *entry,

           struct bfd_hash_table *table,

           const char *string)

{

  struct coff_link_hash_entry *ret = (struct coff_link_hash_entry *) entry;

  /* Allocate the structure if it has not already been allocated by a

     subclass.  */

  if (ret == (struct coff_link_hash_entry *) NULL)

    ret = ((struct coff_link_hash_entry *)

     bfd_hash_allocate (table, sizeof (struct coff_link_hash_entry)));

  if (ret == (struct coff_link_hash_entry *) NULL)

    return (struct bfd_hash_entry *) ret;

  /* Call the allocation method of the superclass.  */

  ret = ((struct coff_link_hash_entry *)

   _bfd_link_hash_newfunc ((struct bfd_hash_entry *) ret,

         table, string));

  if (ret != (struct coff_link_hash_entry *) NULL)

    {

      /* Set local fields.  */

      ret->indx = -1;

      ret->type = T_NULL;

      ret->symbol_class = C_NULL;

      ret->numaux = 0;

      ret->auxbfd = NULL;

      ret->aux = NULL;

    }

  return (struct bfd_hash_entry *) ret;

}

struct bfd_hash_entry *

_decoration_hash_newfunc (struct bfd_hash_entry *entry,

        struct bfd_hash_table *table,

        const char *string)

{

  struct decoration_hash_entry *ret = (struct decoration_hash_entry *) entry;

  /* Allocate the structure if it has not already been allocated by a

     subclass.  */

  if (ret == NULL)

    {

      ret = (struct decoration_hash_entry *)

      bfd_hash_allocate (table, sizeof (struct decoration_hash_entry));

      if (ret == NULL)

  return NULL;

    }

  /* Call the allocation method of the superclass.  */

  ret = (struct decoration_hash_entry *)

  _bfd_link_hash_newfunc ((struct bfd_hash_entry *) ret, table, string);

  if (ret != NULL)

    {

      ret->decorated_link = NULL;

    }

  return (struct bfd_hash_entry *) ret;

}

/* Initialize a COFF linker hash table.  */

bool

_bfd_coff_link_hash_table_init (struct coff_link_hash_table *table,

        bfd *abfd,

        struct bfd_hash_entry *(*newfunc) (struct bfd_hash_entry *,

                   struct bfd_hash_table *,

                   const char *),

        unsigned int entsize)

{

  memset (&table->stab_info, 0, sizeof (table->stab_info));

  return bfd_hash_table_init (&table->decoration_hash,

            _decoration_hash_newfunc,

            sizeof (struct decoration_hash_entry))

   &&_bfd_link_hash_table_init (&table->root, abfd, newfunc, entsize);

}

/* Create a COFF linker hash table.  */

struct bfd_link_hash_table *

_bfd_coff_link_hash_table_create (bfd *abfd)

{

  struct coff_link_hash_table *ret;

  size_t amt = sizeof (struct coff_link_hash_table);

  ret = (struct coff_link_hash_table *) bfd_malloc (amt);

  if (ret == NULL)

    return NULL;

  if (! _bfd_coff_link_hash_table_init (ret, abfd,

          _bfd_coff_link_hash_newfunc,

          sizeof (struct coff_link_hash_entry)))

    {

      free (ret);

      return (struct bfd_link_hash_table *) NULL;

    }

  return &ret->root;

}

/* Create an entry in a COFF debug merge hash table.  */

struct bfd_hash_entry *

_bfd_coff_debug_merge_hash_newfunc (struct bfd_hash_entry *entry,

            struct bfd_hash_table *table,

            const char *string)

{

  struct coff_debug_merge_hash_entry *ret =

    (struct coff_debug_merge_hash_entry *) entry;

  /* Allocate the structure if it has not already been allocated by a

     subclass.  */

  if (ret == (struct coff_debug_merge_hash_entry *) NULL)

    ret = ((struct coff_debug_merge_hash_entry *)

     bfd_hash_allocate (table,

            sizeof (struct coff_debug_merge_hash_entry)));

  if (ret == (struct coff_debug_merge_hash_entry *) NULL)

    return (struct bfd_hash_entry *) ret;

  /* Call the allocation method of the superclass.  */

  ret = ((struct coff_debug_merge_hash_entry *)

   bfd_hash_newfunc ((struct bfd_hash_entry *) ret, table, string));

  if (ret != (struct coff_debug_merge_hash_entry *) NULL)

    {

      /* Set local fields.  */

      ret->types = NULL;

    }

  return (struct bfd_hash_entry *) ret;

}

/* Given a COFF BFD, add symbols to the global hash table as

   appropriate.  */

bool

_bfd_coff_link_add_symbols (bfd *abfd, struct bfd_link_info *info)

{

  switch (bfd_get_format (abfd))

    {

    case bfd_object:

      return coff_link_add_object_symbols (abfd, info);

    case bfd_archive:

      return _bfd_generic_link_add_archive_symbols

  (abfd, info, coff_link_check_archive_element);

    default:

      bfd_set_error (bfd_error_wrong_format);

      return false;

    }

}

/* Add symbols from a COFF object file.  */

static bool

coff_link_add_object_symbols (bfd *abfd, struct bfd_link_info *info)

{

  if (! _bfd_coff_get_external_symbols (abfd))

    return false;

  if (! coff_link_add_symbols (abfd, info))

    return false;

  if (! info->keep_memory

      && ! _bfd_coff_free_symbols (abfd))

    return false;

  return true;

}

/* Check a single archive element to see if we need to include it in

   the link.  *PNEEDED is set according to whether this element is

   needed in the link or not.  This is called via

   _bfd_generic_link_add_archive_symbols.  */

static bool

coff_link_check_archive_element (bfd *abfd,

         struct bfd_link_info *info,

         struct bfd_link_hash_entry *h,

         const char *name,

         bool *pneeded)

{

  *pneeded = false;

  /* PR 22369 - Skip non COFF objects in the archive.  */

  if (! bfd_family_coff (abfd))

    return true;

  /* We are only interested in symbols that are currently undefined.

     If a symbol is currently known to be common, COFF linkers do not

     bring in an object file which defines it.  */

  if (h->type != bfd_link_hash_undefined)

    return true;

  /* If the archive element has already been loaded then one

     of the symbols defined by that element might have been

     made undefined due to being in a discarded section.  */

  if (((struct coff_link_hash_entry *) h)->indx == -3)

    return true;

  /* Include this element?  */

  if (!(*info->callbacks->add_archive_element) (info, abfd, name, &abfd))

    return true;

  *pneeded = true;

  return bfd_link_add_symbols (abfd, info);

}

/* Add all the symbols from an object file to the hash table.  */

static bool

coff_link_add_symbols (bfd *abfd,

           struct bfd_link_info *info)

{

  unsigned int n_tmask = coff_data (abfd)->local_n_tmask;

  unsigned int n_btshft = coff_data (abfd)->local_n_btshft;

  unsigned int n_btmask = coff_data (abfd)->local_n_btmask;

  bool keep_syms;

  bool default_copy;

  bfd_size_type symcount;

  struct coff_link_hash_entry **sym_hash;

  bfd_size_type symesz;

  bfd_byte *esym;

  bfd_byte *esym_end;

  bfd_size_type amt;

  symcount = obj_raw_syment_count (abfd);

  if (symcount == 0)

    return true;   /* Nothing to do.  */

  /* Keep the symbols during this function, in case the linker needs

     to read the generic symbols in order to report an error message.  */

  keep_syms = obj_coff_keep_syms (abfd);

  obj_coff_keep_syms (abfd) = true;

  if (info->keep_memory)

    default_copy = false;

  else

    default_copy = true;

  /* We keep a list of the linker hash table entries that correspond

     to particular symbols.  */

  amt = symcount * sizeof (struct coff_link_hash_entry *);

  sym_hash = (struct coff_link_hash_entry **) bfd_zalloc (abfd, amt);

  if (sym_hash == NULL)

    goto error_return;

  obj_coff_sym_hashes (abfd) = sym_hash;

  symesz = bfd_coff_symesz (abfd);

  BFD_ASSERT (symesz == bfd_coff_auxesz (abfd));

  esym = (bfd_byte *) obj_coff_external_syms (abfd);

  esym_end = esym + symcount * symesz;

  while (esym < esym_end)

    {

      struct internal_syment sym;

      enum coff_symbol_classification classification;

      bool copy;

      bfd_coff_swap_sym_in (abfd, esym, &sym);

      classification = bfd_coff_classify_symbol (abfd, &sym);

      if (classification != COFF_SYMBOL_LOCAL)

  {

    const char *name;

    char buf[SYMNMLEN + 1];

    flagword flags;

    asection *section;

    bfd_vma value;

    bool addit;

    bool discarded = false;

    /* This symbol is externally visible.  */

    name = _bfd_coff_internal_syment_name (abfd, &sym, buf);

    if (name == NULL)

      goto error_return;

    /* We must copy the name into memory if we got it from the

       syment itself, rather than the string table.  */

    copy = default_copy;

    if (sym._n._n_n._n_zeroes != 0

        || sym._n._n_n._n_offset == 0)

      copy = true;

    value = sym.n_value;

    switch (classification)

      {

      default:

        abort ();

      case COFF_SYMBOL_GLOBAL:

        flags = BSF_EXPORT | BSF_GLOBAL;

        section = coff_section_from_bfd_index (abfd, sym.n_scnum);

        if (discarded_section (section))

    {

      discarded = true;

      section = bfd_und_section_ptr;

    }

        else if (! obj_pe (abfd))

    value -= section->vma;

        break;

      case COFF_SYMBOL_UNDEFINED:

        flags = 0;

        section = bfd_und_section_ptr;

        break;

      case COFF_SYMBOL_COMMON:

        flags = BSF_GLOBAL;

        section = bfd_com_section_ptr;

        break;

      case COFF_SYMBOL_PE_SECTION:

        flags = BSF_SECTION_SYM | BSF_GLOBAL;

        section = coff_section_from_bfd_index (abfd, sym.n_scnum);

        if (discarded_section (section))

    section = bfd_und_section_ptr;

        break;

      }

    if (IS_WEAK_EXTERNAL (abfd, sym))

      flags = BSF_WEAK;

    addit = true;

    /* In the PE format, section symbols actually refer to the

       start of the output section.  We handle them specially

       here.  */

    if (obj_pe (abfd) && (flags & BSF_SECTION_SYM) != 0)

      {

        *sym_hash = coff_link_hash_lookup (coff_hash_table (info),

             name, false, copy, false);

        if (*sym_hash != NULL)

    {

      if (((*sym_hash)->coff_link_hash_flags

           & COFF_LINK_HASH_PE_SECTION_SYMBOL) == 0

          && (*sym_hash)->root.type != bfd_link_hash_undefined

          && (*sym_hash)->root.type != bfd_link_hash_undefweak)

        _bfd_error_handler

          (_("warning: symbol `%s' is both section and non-section"),

           name);

      addit = false;

    }

      }

    /* The Microsoft Visual C compiler does string pooling by

       hashing the constants to an internal symbol name, and

       relying on the linker comdat support to discard

       duplicate names.  However, if one string is a literal and

       one is a data initializer, one will end up in the .data

       section and one will end up in the .rdata section.  The

       Microsoft linker will combine them into the .data

       section, which seems to be wrong since it might cause the

       literal to change.

       As long as there are no external references to the

       symbols, which there shouldn't be, we can treat the .data

       and .rdata instances as separate symbols.  The comdat

       code in the linker will do the appropriate merging.  Here

       we avoid getting a multiple definition error for one of

       these special symbols.

       FIXME: I don't think this will work in the case where

       there are two object files which use the constants as a

       literal and two object files which use it as a data

       initializer.  One or the other of the second object files

       is going to wind up with an inappropriate reference.  */

    if (obj_pe (abfd)

        && (classification == COFF_SYMBOL_GLOBAL

      || classification == COFF_SYMBOL_PE_SECTION)

        && coff_section_data (abfd, section) != NULL

        && coff_section_data (abfd, section)->comdat != NULL

        && startswith (name, "??_")

        && strcmp (name, coff_section_data (abfd, section)->comdat->name) == 0)

      {

        if (*sym_hash == NULL)

    *sym_hash = coff_link_hash_lookup (coff_hash_table (info),

               name, false, copy, false);

        if (*sym_hash != NULL

      && (*sym_hash)->root.type == bfd_link_hash_defined

      && coff_section_data (abfd, (*sym_hash)->root.u.def.section)->comdat != NULL

      && strcmp (coff_section_data (abfd, (*sym_hash)->root.u.def.section)->comdat->name,

           coff_section_data (abfd, section)->comdat->name) == 0)

    addit = false;

      }

    if (addit)

      {

        if (! (bfd_coff_link_add_one_symbol

         (info, abfd, name, flags, section, value,

          (const char *) NULL, copy, false,

          (struct bfd_link_hash_entry **) sym_hash)))

    goto error_return;

        if (discarded)

    (*sym_hash)->indx = -3;

      }

    if (obj_pe (abfd) && (flags & BSF_SECTION_SYM) != 0)

      (*sym_hash)->coff_link_hash_flags |=

        COFF_LINK_HASH_PE_SECTION_SYMBOL;

    /* Limit the alignment of a common symbol to the possible

       alignment of a section.  There is no point to permitting

       a higher alignment for a common symbol: we can not

       guarantee it, and it may cause us to allocate extra space

       in the common section.  */

    if (section == bfd_com_section_ptr

        && (*sym_hash)->root.type == bfd_link_hash_common

        && ((*sym_hash)->root.u.c.p->alignment_power

      > bfd_coff_default_section_alignment_power (abfd)))

      (*sym_hash)->root.u.c.p->alignment_power

        = bfd_coff_default_section_alignment_power (abfd);

    if (bfd_get_flavour (info->output_bfd) == bfd_get_flavour (abfd))

      {

        /* If we don't have any symbol information currently in

     the hash table, or if we are looking at a symbol

     definition, then update the symbol class and type in

     the hash table.  */

        if (((*sym_hash)->symbol_class == C_NULL

       && (*sym_hash)->type == T_NULL)

      || sym.n_scnum != 0

      || (sym.n_value != 0

          && (*sym_hash)->root.type != bfd_link_hash_defined

          && (*sym_hash)->root.type != bfd_link_hash_defweak))

    {

      (*sym_hash)->symbol_class = sym.n_sclass;

      if (sym.n_type != T_NULL)

        {

          /* We want to warn if the type changed, but not

       if it changed from an unspecified type.

       Testing the whole type byte may work, but the

       change from (e.g.) a function of unspecified

       type to function of known type also wants to

       skip the warning.  */

          if ((*sym_hash)->type != T_NULL

        && (*sym_hash)->type != sym.n_type

        && !(DTYPE ((*sym_hash)->type) == DTYPE (sym.n_type)

             && (BTYPE ((*sym_hash)->type) == T_NULL

           || BTYPE (sym.n_type) == T_NULL)))

      _bfd_error_handler

        /* xgettext: c-format */

        (_("warning: type of symbol `%s' changed"

           " from %d to %d in %pB"),

         name, (*sym_hash)->type, sym.n_type, abfd);

          /* We don't want to change from a meaningful

       base type to a null one, but if we know

       nothing, take what little we might now know.  */

          if (BTYPE (sym.n_type) != T_NULL

        || (*sym_hash)->type == T_NULL)

      (*sym_hash)->type = sym.n_type;

        }

      (*sym_hash)->auxbfd = abfd;

      if (sym.n_numaux != 0)

        {

          union internal_auxent *alloc;

          unsigned int i;

          bfd_byte *eaux;

          union internal_auxent *iaux;

          (*sym_hash)->numaux = sym.n_numaux;

          alloc = ((union internal_auxent *)

             bfd_hash_allocate (&info->hash->table,

              (sym.n_numaux

               * sizeof (*alloc))));

          if (alloc == NULL)

      goto error_return;

          for (i = 0, eaux = esym + symesz, iaux = alloc;

         i < sym.n_numaux;

         i++, eaux += symesz, iaux++)

      bfd_coff_swap_aux_in (abfd, eaux, sym.n_type,

                sym.n_sclass, (int) i,

                sym.n_numaux, iaux);

          (*sym_hash)->aux = alloc;

        }

    }

      }

    if (classification == COFF_SYMBOL_PE_SECTION

        && (*sym_hash)->numaux != 0)

      {

        /* Some PE sections (such as .bss) have a zero size in

     the section header, but a non-zero size in the AUX

     record.  Correct that here.

     FIXME: This is not at all the right place to do this.

     For example, it won't help objdump.  This needs to be

     done when we swap in the section header.  */

        BFD_ASSERT ((*sym_hash)->numaux == 1);

        if (section->size == 0)

    section->size = (*sym_hash)->aux[0].x_scn.x_scnlen;

        /* FIXME: We could test whether the section sizes

     matches the size in the aux entry, but apparently

     that sometimes fails unexpectedly.  */

      }

  }

      esym += (sym.n_numaux + 1) * symesz;

      sym_hash += sym.n_numaux + 1;

    }

  /* If this is a non-traditional, non-relocatable link, try to

     optimize the handling of any .stab/.stabstr sections.  */

  if (! bfd_link_relocatable (info)

      && ! info->traditional_format

      && bfd_get_flavour (info->output_bfd) == bfd_get_flavour (abfd)

      && (info->strip != strip_all && info->strip != strip_debugger))

    {

      asection *stabstr;

      stabstr = bfd_get_section_by_name (abfd, ".stabstr");

      if (stabstr != NULL)

  {

    bfd_size_type string_offset = 0;

    asection *stab;

    for (stab = abfd->sections; stab; stab = stab->next)

      if (startswith (stab->name, ".stab")

    && (!stab->name[5]

        || (stab->name[5] == '.' && ISDIGIT (stab->name[6]))))

      {

        struct coff_link_hash_table *table;

        struct coff_section_tdata *secdata

    = coff_section_data (abfd, stab);

        if (secdata == NULL)

    {

      amt = sizeof (struct coff_section_tdata);

      stab->used_by_bfd = bfd_zalloc (abfd, amt);

      if (stab->used_by_bfd == NULL)

        goto error_return;

      secdata = coff_section_data (abfd, stab);

    }

        table = coff_hash_table (info);

        if (! _bfd_link_section_stabs (abfd, &table->stab_info,

               stab, stabstr,

               &secdata->stab_info,

               &string_offset))

    goto error_return;

      }

  }

    }

  obj_coff_keep_syms (abfd) = keep_syms;

  return true;

 error_return:

  obj_coff_keep_syms (abfd) = keep_syms;

  return false;

}

/* Do the final link step.  */

bool

_bfd_coff_final_link (bfd *abfd,

          struct bfd_link_info *info)

{

  bfd_size_type symesz;

  struct coff_final_link_info flaginfo;

  bool debug_merge_allocated;

  bool long_section_names;

  asection *o;

  struct bfd_link_order *p;

  bfd_size_type max_sym_count;

  bfd_size_type max_lineno_count;

  bfd_size_type max_reloc_count;

  bfd_size_type max_output_reloc_count;

  bfd_size_type max_contents_size;

  file_ptr rel_filepos;

  unsigned int relsz;

  file_ptr line_filepos;

  unsigned int linesz;

  bfd *sub;

  bfd_byte *external_relocs = NULL;

  char strbuf[STRING_SIZE_SIZE];

  bfd_size_type amt;

  symesz = bfd_coff_symesz (abfd);

  flaginfo.info = info;

  flaginfo.output_bfd = abfd;

  flaginfo.strtab = NULL;

  flaginfo.section_info = NULL;

  flaginfo.last_file_index = -1;

  flaginfo.last_bf_index = -1;

  flaginfo.internal_syms = NULL;

  flaginfo.sec_ptrs = NULL;

  flaginfo.sym_indices = NULL;

  flaginfo.outsyms = NULL;

  flaginfo.linenos = NULL;

  flaginfo.contents = NULL;

  flaginfo.external_relocs = NULL;

  flaginfo.internal_relocs = NULL;

  flaginfo.global_to_static = false;

  debug_merge_allocated = false;

  coff_data (abfd)->link_info = info;

  flaginfo.strtab = _bfd_stringtab_init ();

  if (flaginfo.strtab == NULL)

    goto error_return;

  if (! coff_debug_merge_hash_table_init (&flaginfo.debug_merge))

    goto error_return;

  debug_merge_allocated = true;

  /* Compute the file positions for all the sections.  */

  if (! abfd->output_has_begun)

    {

      if (! bfd_coff_compute_section_file_positions (abfd))

  goto error_return;

    }

  /* Count the line numbers and relocation entries required for the

     output file.  Set the file positions for the relocs.  */

  rel_filepos = obj_relocbase (abfd);

  relsz = bfd_coff_relsz (abfd);

  max_contents_size = 0;

  max_lineno_count = 0;

  max_reloc_count = 0;

  long_section_names = false;

  for (o = abfd->sections; o != NULL; o = o->next)

    {

      o->reloc_count = 0;

      o->lineno_count = 0;

      for (p = o->map_head.link_order; p != NULL; p = p->next)

  {

    if (p->type == bfd_indirect_link_order)

      {

        asection *sec;

        sec = p->u.indirect.section;

        /* Mark all sections which are to be included in the

     link.  This will normally be every section.  We need

     to do this so that we can identify any sections which

     the linker has decided to not include.  */

        sec->linker_mark = true;

        if (info->strip == strip_none

      || info->strip == strip_some)

    o->lineno_count += sec->lineno_count;

        if (bfd_link_relocatable (info))

    o->reloc_count += sec->reloc_count;

        if (sec->rawsize > max_contents_size)

    max_contents_size = sec->rawsize;

        if (sec->size > max_contents_size)

    max_contents_size = sec->size;

        if (sec->lineno_count > max_lineno_count)

    max_lineno_count = sec->lineno_count;

        if (sec->reloc_count > max_reloc_count)

    max_reloc_count = sec->reloc_count;

      }

    else if (bfd_link_relocatable (info)

       && (p->type == bfd_section_reloc_link_order

           || p->type == bfd_symbol_reloc_link_order))

      ++o->reloc_count;

  }

      if (o->reloc_count == 0)

  o->rel_filepos = 0;

      else

  {

    o->flags |= SEC_RELOC;

    o->rel_filepos = rel_filepos;

    rel_filepos += o->reloc_count * relsz;

    /* In PE COFF, if there are at least 0xffff relocations an

       extra relocation will be written out to encode the count.  */

    if ((obj_pe (abfd) || obj_go32 (abfd)) && o->reloc_count >= 0xffff)

      rel_filepos += relsz;

  }

      if (bfd_coff_long_section_names (abfd)

    && strlen (o->name) > SCNNMLEN)

  {

    /* This section has a long name which must go in the string

       table.  This must correspond to the code in

       coff_write_object_contents which puts the string index

       into the s_name field of the section header.  That is why

       we pass hash as FALSE.  */

    if (_bfd_stringtab_add (flaginfo.strtab, o->name, false, false)

        == (bfd_size_type) -1)

      goto error_return;

    long_section_names = true;

  }

    }

  /* If doing a relocatable link, allocate space for the pointers we

     need to keep.  */

  if (bfd_link_relocatable (info))

    {

      unsigned int i;

      /* We use section_count + 1, rather than section_count, because

   the target_index fields are 1 based.  */

      amt = abfd->section_count + 1;

      amt *= sizeof (struct coff_link_section_info);

      flaginfo.section_info = (struct coff_link_section_info *) bfd_malloc (amt);

      if (flaginfo.section_info == NULL)

  goto error_return;

      for (i = 0; i <= abfd->section_count; i++)

  {

    flaginfo.section_info[i].relocs = NULL;

    flaginfo.section_info[i].rel_hashes = NULL;

  }

    }

  /* We now know the size of the relocs, so we can determine the file

     positions of the line numbers.  */

  line_filepos = rel_filepos;

  linesz = bfd_coff_linesz (abfd);

  max_output_reloc_count = 0;

  for (o = abfd->sections; o != NULL; o = o->next)

    {

      if (o->lineno_count == 0)

  o->line_filepos = 0;

      else

  {

    o->line_filepos = line_filepos;

    line_filepos += o->lineno_count * linesz;

  }

      if (o->reloc_count != 0)

  {

    /* We don't know the indices of global symbols until we have

       written out all the local symbols.  For each section in

       the output file, we keep an array of pointers to hash

       table entries.  Each entry in the array corresponds to a

       reloc.  When we find a reloc against a global symbol, we

       set the corresponding entry in this array so that we can

       fix up the symbol index after we have written out all the

       local symbols.

       Because of this problem, we also keep the relocs in

       memory until the end of the link.  This wastes memory,

       but only when doing a relocatable link, which is not the

       common case.  */

    BFD_ASSERT (bfd_link_relocatable (info));

    amt = o->reloc_count;

    amt *= sizeof (struct internal_reloc);

    flaginfo.section_info[o->target_index].relocs =

        (struct internal_reloc *) bfd_malloc (amt);

    amt = o->reloc_count;

    amt *= sizeof (struct coff_link_hash_entry *);

    flaginfo.section_info[o->target_index].rel_hashes =

        (struct coff_link_hash_entry **) bfd_malloc (amt);

    if (flaginfo.section_info[o->target_index].relocs == NULL

        || flaginfo.section_info[o->target_index].rel_hashes == NULL)

      goto error_return;

    if (o->reloc_count > max_output_reloc_count)

      max_output_reloc_count = o->reloc_count;

  }

      /* Reset the reloc and lineno counts, so that we can use them to

   count the number of entries we have output so far.  */

      o->reloc_count = 0;

      o->lineno_count = 0;

    }

  obj_sym_filepos (abfd) = line_filepos;

  /* Figure out the largest number of symbols in an input BFD.  Take

     the opportunity to clear the output_has_begun fields of all the

     input BFD's.  */

  max_sym_count = 0;

  for (sub = info->input_bfds; sub != NULL; sub = sub->link.next)

    {

      size_t sz;

      sub->output_has_begun = false;

      sz = bfd_family_coff (sub) ? obj_raw_syment_count (sub) : 2;

      if (sz > max_sym_count)

  max_sym_count = sz;

    }

  /* Allocate some buffers used while linking.  */

  amt = max_sym_count * sizeof (struct internal_syment);

  flaginfo.internal_syms = (struct internal_syment *) bfd_malloc (amt);

  amt = max_sym_count * sizeof (asection *);

  flaginfo.sec_ptrs = (asection **) bfd_malloc (amt);

  amt = max_sym_count * sizeof (long);

  flaginfo.sym_indices = (long int *) bfd_malloc (amt);

  flaginfo.outsyms = (bfd_byte *) bfd_malloc ((max_sym_count + 1) * symesz);

  amt = max_lineno_count * bfd_coff_linesz (abfd);

  flaginfo.linenos = (bfd_byte *) bfd_malloc (amt);

  flaginfo.contents = (bfd_byte *) bfd_malloc (max_contents_size);

  amt = max_reloc_count * relsz;

  flaginfo.external_relocs = (bfd_byte *) bfd_malloc (amt);

  if (! bfd_link_relocatable (info))

    {

      amt = max_reloc_count * sizeof (struct internal_reloc);

      flaginfo.internal_relocs = (struct internal_reloc *) bfd_malloc (amt);

    }

  if ((flaginfo.internal_syms == NULL && max_sym_count > 0)

      || (flaginfo.sec_ptrs == NULL && max_sym_count > 0)

      || (flaginfo.sym_indices == NULL && max_sym_count > 0)

      || flaginfo.outsyms == NULL

      || (flaginfo.linenos == NULL && max_lineno_count > 0)

      || (flaginfo.contents == NULL && max_contents_size > 0)

      || (flaginfo.external_relocs == NULL && max_reloc_count > 0)

      || (! bfd_link_relocatable (info)

    && flaginfo.internal_relocs == NULL

    && max_reloc_count > 0))

    goto error_return;

  /* We now know the position of everything in the file, except that

     we don't know the size of the symbol table and therefore we don't

     know where the string table starts.  We just build the string

     table in memory as we go along.  We process all the relocations

     for a single input file at once.  */

  obj_raw_syment_count (abfd) = 0;

  if (coff_backend_info (abfd)->_bfd_coff_start_final_link)

    {