ld/pdb.c

/* Support for generating PDB CodeView debugging files.
   Copyright (C) 2022-2024 Free Software Foundation, Inc.

   This file is part of the GNU Binutils.

   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.  */

#include "pdb.h"
#include "bfdlink.h"
#include "ld.h"
#include "ldmain.h"
#include "ldmisc.h"
#include "libbfd.h"
#include "libiberty.h"
#include "coff/i386.h"
#include "coff/external.h"
#include "coff/internal.h"
#include "coff/pe.h"
#include "libcoff.h"
#include <time.h>

struct public
{
  struct public *next;
  uint32_t offset;
  uint32_t hash;
  unsigned int index;
  uint16_t section;
  uint32_t address;
};

struct string
{
  struct string *next;
  uint32_t hash;
  uint32_t offset;
  uint32_t source_file_offset;
  size_t len;
  char s[];
};

struct string_table
{
  struct string *strings_head;
  struct string *strings_tail;
  uint32_t strings_len;
  htab_t hashmap;
};

struct mod_source_files
{
  uint16_t files_count;
  struct string **files;
};

struct source_files_info
{
  uint16_t mod_count;
  struct mod_source_files *mods;
};

struct type_entry
{
  struct type_entry *next;
  uint32_t index;
  uint32_t cv_hash;
  bool has_udt_src_line;
  uint8_t data[];
};

struct types
{
  htab_t hashmap;
  uint32_t num_types;
  struct type_entry *first;
  struct type_entry *last;
};

struct global
{
  struct global *next;
  uint32_t offset;
  uint32_t hash;
  uint32_t refcount;
  unsigned int index;
  uint8_t data[];
};

struct globals
{
  uint32_t num_entries;
  struct global *first;
  struct global *last;
  htab_t hashmap;
};

struct in_sc
{
  asection *s;
  uint16_t sect_num;
  uint16_t mod_index;
};

static const uint32_t crc_table[] =
{
  0x00000000, 0x77073096, 0xee0e612c, 0x990951ba, 0x076dc419, 0x706af48f,
  0xe963a535, 0x9e6495a3, 0x0edb8832, 0x79dcb8a4, 0xe0d5e91e, 0x97d2d988,
  0x09b64c2b, 0x7eb17cbd, 0xe7b82d07, 0x90bf1d91, 0x1db71064, 0x6ab020f2,
  0xf3b97148, 0x84be41de, 0x1adad47d, 0x6ddde4eb, 0xf4d4b551, 0x83d385c7,
  0x136c9856, 0x646ba8c0, 0xfd62f97a, 0x8a65c9ec, 0x14015c4f, 0x63066cd9,
  0xfa0f3d63, 0x8d080df5, 0x3b6e20c8, 0x4c69105e, 0xd56041e4, 0xa2677172,
  0x3c03e4d1, 0x4b04d447, 0xd20d85fd, 0xa50ab56b, 0x35b5a8fa, 0x42b2986c,
  0xdbbbc9d6, 0xacbcf940, 0x32d86ce3, 0x45df5c75, 0xdcd60dcf, 0xabd13d59,
  0x26d930ac, 0x51de003a, 0xc8d75180, 0xbfd06116, 0x21b4f4b5, 0x56b3c423,
  0xcfba9599, 0xb8bda50f, 0x2802b89e, 0x5f058808, 0xc60cd9b2, 0xb10be924,
  0x2f6f7c87, 0x58684c11, 0xc1611dab, 0xb6662d3d, 0x76dc4190, 0x01db7106,
  0x98d220bc, 0xefd5102a, 0x71b18589, 0x06b6b51f, 0x9fbfe4a5, 0xe8b8d433,
  0x7807c9a2, 0x0f00f934, 0x9609a88e, 0xe10e9818, 0x7f6a0dbb, 0x086d3d2d,
  0x91646c97, 0xe6635c01, 0x6b6b51f4, 0x1c6c6162, 0x856530d8, 0xf262004e,
  0x6c0695ed, 0x1b01a57b, 0x8208f4c1, 0xf50fc457, 0x65b0d9c6, 0x12b7e950,
  0x8bbeb8ea, 0xfcb9887c, 0x62dd1ddf, 0x15da2d49, 0x8cd37cf3, 0xfbd44c65,
  0x4db26158, 0x3ab551ce, 0xa3bc0074, 0xd4bb30e2, 0x4adfa541, 0x3dd895d7,
  0xa4d1c46d, 0xd3d6f4fb, 0x4369e96a, 0x346ed9fc, 0xad678846, 0xda60b8d0,
  0x44042d73, 0x33031de5, 0xaa0a4c5f, 0xdd0d7cc9, 0x5005713c, 0x270241aa,
  0xbe0b1010, 0xc90c2086, 0x5768b525, 0x206f85b3, 0xb966d409, 0xce61e49f,
  0x5edef90e, 0x29d9c998, 0xb0d09822, 0xc7d7a8b4, 0x59b33d17, 0x2eb40d81,
  0xb7bd5c3b, 0xc0ba6cad, 0xedb88320, 0x9abfb3b6, 0x03b6e20c, 0x74b1d29a,
  0xead54739, 0x9dd277af, 0x04db2615, 0x73dc1683, 0xe3630b12, 0x94643b84,
  0x0d6d6a3e, 0x7a6a5aa8, 0xe40ecf0b, 0x9309ff9d, 0x0a00ae27, 0x7d079eb1,
  0xf00f9344, 0x8708a3d2, 0x1e01f268, 0x6906c2fe, 0xf762575d, 0x806567cb,
  0x196c3671, 0x6e6b06e7, 0xfed41b76, 0x89d32be0, 0x10da7a5a, 0x67dd4acc,
  0xf9b9df6f, 0x8ebeeff9, 0x17b7be43, 0x60b08ed5, 0xd6d6a3e8, 0xa1d1937e,
  0x38d8c2c4, 0x4fdff252, 0xd1bb67f1, 0xa6bc5767, 0x3fb506dd, 0x48b2364b,
  0xd80d2bda, 0xaf0a1b4c, 0x36034af6, 0x41047a60, 0xdf60efc3, 0xa867df55,
  0x316e8eef, 0x4669be79, 0xcb61b38c, 0xbc66831a, 0x256fd2a0, 0x5268e236,
  0xcc0c7795, 0xbb0b4703, 0x220216b9, 0x5505262f, 0xc5ba3bbe, 0xb2bd0b28,
  0x2bb45a92, 0x5cb36a04, 0xc2d7ffa7, 0xb5d0cf31, 0x2cd99e8b, 0x5bdeae1d,
  0x9b64c2b0, 0xec63f226, 0x756aa39c, 0x026d930a, 0x9c0906a9, 0xeb0e363f,
  0x72076785, 0x05005713, 0x95bf4a82, 0xe2b87a14, 0x7bb12bae, 0x0cb61b38,
  0x92d28e9b, 0xe5d5be0d, 0x7cdcefb7, 0x0bdbdf21, 0x86d3d2d4, 0xf1d4e242,
  0x68ddb3f8, 0x1fda836e, 0x81be16cd, 0xf6b9265b, 0x6fb077e1, 0x18b74777,
  0x88085ae6, 0xff0f6a70, 0x66063bca, 0x11010b5c, 0x8f659eff, 0xf862ae69,
  0x616bffd3, 0x166ccf45, 0xa00ae278, 0xd70dd2ee, 0x4e048354, 0x3903b3c2,
  0xa7672661, 0xd06016f7, 0x4969474d, 0x3e6e77db, 0xaed16a4a, 0xd9d65adc,
  0x40df0b66, 0x37d83bf0, 0xa9bcae53, 0xdebb9ec5, 0x47b2cf7f, 0x30b5ffe9,
  0xbdbdf21c, 0xcabac28a, 0x53b39330, 0x24b4a3a6, 0xbad03605, 0xcdd70693,
  0x54de5729, 0x23d967bf, 0xb3667a2e, 0xc4614ab8, 0x5d681b02, 0x2a6f2b94,
  0xb40bbe37, 0xc30c8ea1, 0x5a05df1b, 0x2d02ef8d
};

/* Add a new stream to the PDB archive, and return its BFD.  */
static bfd *
add_stream (bfd *pdb, const char *name, uint16_t *stream_num)
{
  bfd *stream;
  uint16_t num;

  stream = bfd_create (name ? name : "", pdb);
  if (!stream)
    return NULL;

  if (!bfd_make_writable (stream))
    {
      bfd_close (stream);
      return false;
    }

  if (!pdb->archive_head)
    {
      bfd_set_archive_head (pdb, stream);
      num = 0;
    }
  else
    {
      bfd *b = pdb->archive_head;

      num = 1;

      while (b->archive_next)
	{
	  num++;
	  b = b->archive_next;
	}

      b->archive_next = stream;
    }

  if (stream_num)
    *stream_num = num;

  return stream;
}

/* Stream 0 ought to be a copy of the MSF directory from the last
   time the PDB file was written.  Because we don't do incremental
   writes this isn't applicable to us, but we fill it with a dummy
   value so as not to confuse radare.  */
static bool
create_old_directory_stream (bfd *pdb)
{
  bfd *stream;
  char buf[sizeof (uint32_t)];

  stream = add_stream (pdb, NULL, NULL);
  if (!stream)
    return false;

  bfd_putl32 (0, buf);

  return bfd_write (buf, sizeof (uint32_t), stream) == sizeof (uint32_t);
}

/* Calculate the hash of a given string.  */
static uint32_t
calc_hash (const char *data, size_t len)
{
  uint32_t hash = 0;

  while (len >= 4)
    {
      hash ^= data[0];
      hash ^= data[1] << 8;
      hash ^= data[2] << 16;
      hash ^= data[3] << 24;

      data += 4;
      len -= 4;
    }

  if (len >= 2)
    {
      hash ^= data[0];
      hash ^= data[1] << 8;

      data += 2;
      len -= 2;
    }

  if (len != 0)
    hash ^= *data;

  hash |= 0x20202020;
  hash ^= (hash >> 11);

  return hash ^ (hash >> 16);
}

/* Stream 1 is the PDB info stream - see
   https://llvm.org/docs/PDB/PdbStream.html.  */
static bool
populate_info_stream (bfd *pdb, bfd *info_stream, const unsigned char *guid)
{
  bool ret = false;
  struct pdb_stream_70 h;
  uint32_t num_entries, num_buckets;
  uint32_t names_length, stream_num;
  char int_buf[sizeof (uint32_t)];

  struct hash_entry
  {
    uint32_t offset;
    uint32_t value;
  };

  struct hash_entry **buckets = NULL;

  /* Write header.  */

  bfd_putl32 (PDB_STREAM_VERSION_VC70, &h.version);
  bfd_putl32 (time (NULL), &h.signature);
  bfd_putl32 (1, &h.age);

  bfd_putl32 (bfd_getb32 (guid), h.guid);
  bfd_putl16 (bfd_getb16 (&guid[4]), &h.guid[4]);
  bfd_putl16 (bfd_getb16 (&guid[6]), &h.guid[6]);
  memcpy (&h.guid[8], &guid[8], 8);

  if (bfd_write (&h, sizeof (h), info_stream) != sizeof (h))
    return false;

  /* Write hash list of named streams.  This is a "rollover" hash, i.e.
     if a bucket is filled an entry gets placed in the next free
     slot.  */

  num_entries = 0;
  for (bfd *b = pdb->archive_head; b; b = b->archive_next)
    {
      if (strcmp (b->filename, ""))
	num_entries++;
    }

  num_buckets = num_entries * 2;

  names_length = 0;
  stream_num = 0;

  if (num_buckets > 0)
    {
      buckets = xmalloc (sizeof (struct hash_entry *) * num_buckets);
      memset (buckets, 0, sizeof (struct hash_entry *) * num_buckets);

      for (bfd *b = pdb->archive_head; b; b = b->archive_next)
	{
	  if (strcmp (b->filename, ""))
	    {
	      size_t len = strlen (b->filename);
	      uint32_t hash = (uint16_t) calc_hash (b->filename, len);
	      uint32_t bucket_num = hash % num_buckets;

	      while (buckets[bucket_num])
		{
		  bucket_num++;

		  if (bucket_num == num_buckets)
		    bucket_num = 0;
		}

	      buckets[bucket_num] = xmalloc (sizeof (struct hash_entry));

	      buckets[bucket_num]->offset = names_length;
	      buckets[bucket_num]->value = stream_num;

	      names_length += len + 1;
	    }

	  stream_num++;
	}
    }

  /* Write the strings list - the hash keys are indexes into this.  */

  bfd_putl32 (names_length, int_buf);

  if (bfd_write (int_buf, sizeof (uint32_t), info_stream) !=
      sizeof (uint32_t))
    goto end;

  for (bfd *b = pdb->archive_head; b; b = b->archive_next)
    {
      if (!strcmp (b->filename, ""))
	continue;

      size_t len = strlen (b->filename) + 1;

      if (bfd_write (b->filename, len, info_stream) != len)
	goto end;
    }

  /* Write the number of entries and buckets.  */

  bfd_putl32 (num_entries, int_buf);

  if (bfd_write (int_buf, sizeof (uint32_t), info_stream) !=
      sizeof (uint32_t))
    goto end;

  bfd_putl32 (num_buckets, int_buf);

  if (bfd_write (int_buf, sizeof (uint32_t), info_stream) !=
      sizeof (uint32_t))
    goto end;

  /* Write the present bitmap.  */

  bfd_putl32 ((num_buckets + 31) / 32, int_buf);

  if (bfd_write (int_buf, sizeof (uint32_t), info_stream) !=
      sizeof (uint32_t))
    goto end;

  for (unsigned int i = 0; i < num_buckets; i += 32)
    {
      uint32_t v = 0;

      for (unsigned int j = 0; j < 32; j++)
	{
	  if (i + j >= num_buckets)
	    break;

	  if (buckets[i + j])
	    v |= 1 << j;
	}

      bfd_putl32 (v, int_buf);

      if (bfd_write (int_buf, sizeof (uint32_t), info_stream) !=
	  sizeof (uint32_t))
	goto end;
    }

  /* Write the (empty) deleted bitmap.  */

  bfd_putl32 (0, int_buf);

  if (bfd_write (int_buf, sizeof (uint32_t), info_stream) !=
      sizeof (uint32_t))
    goto end;

  /* Write the buckets.  */

  for (unsigned int i = 0; i < num_buckets; i++)
    {
      if (buckets[i])
	{
	  bfd_putl32 (buckets[i]->offset, int_buf);

	  if (bfd_write (int_buf, sizeof (uint32_t), info_stream) !=
	      sizeof (uint32_t))
	    goto end;

	  bfd_putl32 (buckets[i]->value, int_buf);

	  if (bfd_write (int_buf, sizeof (uint32_t), info_stream) !=
	      sizeof (uint32_t))
	    goto end;
	}
    }

  bfd_putl32 (0, int_buf);

  if (bfd_write (int_buf, sizeof (uint32_t), info_stream) !=
      sizeof (uint32_t))
    goto end;

  bfd_putl32 (PDB_STREAM_VERSION_VC140, int_buf);

  if (bfd_write (int_buf, sizeof (uint32_t), info_stream) !=
      sizeof (uint32_t))
    goto end;

  ret = true;

end:
  for (unsigned int i = 0; i < num_buckets; i++)
    {
      if (buckets[i])
	free (buckets[i]);
    }

  free (buckets);

  return ret;
}

/* Calculate the CRC32 used for type hashes.  */
static uint32_t
crc32 (const uint8_t *data, size_t len)
{
  uint32_t crc = 0;

  while (len > 0)
    {
      crc = (crc >> 8) ^ crc_table[(crc & 0xff) ^ *data];

      data++;
      len--;
    }

  return crc;
}

/* Stream 2 is the type information (TPI) stream, and stream 4 is
   the ID information (IPI) stream.  They differ only in which records
   go in which stream. */
static bool
populate_type_stream (bfd *pdb, bfd *stream, struct types *types)
{
  struct pdb_tpi_stream_header h;
  struct type_entry *e;
  uint32_t len = 0, index_offset_len, off;
  struct bfd *hash_stream = NULL;
  uint16_t hash_stream_index;

  static const uint32_t index_skip = 0x2000;

  e = types->first;

  index_offset_len = 0;

  while (e)
    {
      uint32_t old_len = len;

      len += sizeof (uint16_t) + bfd_getl16 (e->data);

      if (old_len == 0 || old_len / index_skip != len / index_skip)
	index_offset_len += sizeof (uint32_t) * 2;

      e = e->next;
    }

  /* Each type stream also has a stream which holds the hash value for each
     type, along with a skip list to speed up searching.  */

  hash_stream = add_stream (pdb, "", &hash_stream_index);

  if (!hash_stream)
    return false;

  bfd_putl32 (TPI_STREAM_VERSION_80, &h.version);
  bfd_putl32 (sizeof (h), &h.header_size);
  bfd_putl32 (TPI_FIRST_INDEX, &h.type_index_begin);
  bfd_putl32 (TPI_FIRST_INDEX + types->num_types, &h.type_index_end);
  bfd_putl32 (len, &h.type_record_bytes);
  bfd_putl16 (hash_stream_index, &h.hash_stream_index);
  bfd_putl16 (0xffff, &h.hash_aux_stream_index);
  bfd_putl32 (sizeof (uint32_t), &h.hash_key_size);
  bfd_putl32 (NUM_TPI_HASH_BUCKETS, &h.num_hash_buckets);
  bfd_putl32 (0, &h.hash_value_buffer_offset);
  bfd_putl32 (types->num_types * sizeof (uint32_t),
	      &h.hash_value_buffer_length);
  bfd_putl32 (types->num_types * sizeof (uint32_t),
	      &h.index_offset_buffer_offset);
  bfd_putl32 (index_offset_len, &h.index_offset_buffer_length);
  bfd_putl32 ((types->num_types * sizeof (uint32_t)) + index_offset_len,
	      &h.hash_adj_buffer_offset);
  bfd_putl32 (0, &h.hash_adj_buffer_length);

  if (bfd_write (&h, sizeof (h), stream) != sizeof (h))
    return false;

  /* Write the type definitions into the main stream, and the hashes
     into the hash stream.  The hashes have already been calculated
     in handle_type.  */

  e = types->first;

  while (e)
    {
      uint8_t buf[sizeof (uint32_t)];
      uint16_t size;

      size = bfd_getl16 (e->data);

      if (bfd_write (e->data, size + sizeof (uint16_t), stream)
	  != size + sizeof (uint16_t))
	return false;

      bfd_putl32 (e->cv_hash % NUM_TPI_HASH_BUCKETS, buf);

      if (bfd_write (buf, sizeof (uint32_t), hash_stream)
	  != sizeof (uint32_t))
	return false;

      e = e->next;
    }

  /* Write the index offsets, i.e. the skip list, into the hash stream.  We
     copy MSVC here by writing a new entry for every 8192 bytes.  */

  e = types->first;
  off = 0;

  while (e)
    {
      uint32_t old_off = off;
      uint16_t size = bfd_getl16 (e->data);

      off += size + sizeof (uint16_t);

      if (old_off == 0 || old_off / index_skip != len / index_skip)
	{
	  uint8_t buf[sizeof (uint32_t)];

	  bfd_putl32 (TPI_FIRST_INDEX + e->index, buf);

	  if (bfd_write (buf, sizeof (uint32_t), hash_stream)
	      != sizeof (uint32_t))
	    return false;

	  bfd_putl32 (old_off, buf);

	  if (bfd_write (buf, sizeof (uint32_t), hash_stream)
	      != sizeof (uint32_t))
	    return false;
	}

      e = e->next;
    }

  return true;
}

/* Return the PE architecture number for the image.  */
static uint16_t
get_arch_number (bfd *abfd)
{
  switch (abfd->arch_info->arch)
    {
    case bfd_arch_i386:
      if (abfd->arch_info->mach & bfd_mach_x86_64)
	return IMAGE_FILE_MACHINE_AMD64;
      else
	return IMAGE_FILE_MACHINE_I386;

    case bfd_arch_aarch64:
      return IMAGE_FILE_MACHINE_ARM64;

    default:
      return 0;
    }
}

/* Validate the DEBUG_S_FILECHKSMS entry within a module's .debug$S
   section, and copy it to the module's symbol stream.  */
static bool
copy_filechksms (uint8_t *data, uint32_t size, char *string_table,
		 struct string_table *strings, uint8_t *out,
		 struct mod_source_files *mod_source)
{
  uint8_t *orig_data = data;
  uint32_t orig_size = size;
  uint16_t num_files = 0;
  struct string **strptr;

  bfd_putl32 (DEBUG_S_FILECHKSMS, out);
  out += sizeof (uint32_t);

  bfd_putl32 (size, out);
  out += sizeof (uint32_t);

  /* Calculate the number of files, and check for any overflows.  */

  while (size > 0)
    {
      struct file_checksum *fc = (struct file_checksum *) data;
      uint8_t padding;
      size_t len;

      if (size < sizeof (struct file_checksum))
	{
	  bfd_set_error (bfd_error_bad_value);
	  return false;
	}

      len = sizeof (struct file_checksum) + fc->checksum_length;

      if (size < len)
	{
	  bfd_set_error (bfd_error_bad_value);
	  return false;
	}

      data += len;
      size -= len;

      if (len % sizeof (uint32_t))
	padding = sizeof (uint32_t) - (len % sizeof (uint32_t));
      else
	padding = 0;

      if (size < padding)
	{
	  bfd_set_error (bfd_error_bad_value);
	  return false;
	}

      num_files++;

      data += padding;
      size -= padding;
    }

  /* Add the files to mod_source, so that they'll appear in the source
     info substream.  */

  strptr = NULL;
  if (num_files > 0)
    {
      uint16_t new_count = num_files + mod_source->files_count;

      mod_source->files = xrealloc (mod_source->files,
				    sizeof (struct string *) * new_count);

      strptr = mod_source->files + mod_source->files_count;

      mod_source->files_count += num_files;
    }

  /* Actually copy the data.  */

  data = orig_data;
  size = orig_size;

  while (size > 0)
    {
      struct file_checksum *fc = (struct file_checksum *) data;
      uint32_t string_off;
      uint8_t padding;
      size_t len;
      struct string *str = NULL;

      string_off = bfd_getl32 (&fc->file_id);
      len = sizeof (struct file_checksum) + fc->checksum_length;

      if (len % sizeof (uint32_t))
	padding = sizeof (uint32_t) - (len % sizeof (uint32_t));
      else
	padding = 0;

      /* Remap the "file ID", i.e. the offset in the module's string table,
	 so it points to the right place in the main string table.  */

      if (string_table)
	{
	  char *fn = string_table + string_off;
	  size_t fn_len = strlen (fn);
	  uint32_t hash = calc_hash (fn, fn_len);
	  void **slot;

	  slot = htab_find_slot_with_hash (strings->hashmap, fn, hash,
					   NO_INSERT);

	  if (slot)
	    str = (struct string *) *slot;
	}

      *strptr = str;
      strptr++;

      bfd_putl32 (str ? str->offset : 0, &fc->file_id);

      memcpy (out, data, len + padding);

      data += len + padding;
      size -= len + padding;
      out += len + padding;
    }

  return true;
}

/* Add a string to the strings table, if it's not already there.  Returns its
   offset within the string table.  */
static uint32_t
add_string (char *str, size_t len, struct string_table *strings)
{
  uint32_t hash = calc_hash (str, len);
  struct string *s;
  void **slot;

  slot = htab_find_slot_with_hash (strings->hashmap, str, hash, INSERT);

  if (!*slot)
    {
      *slot = xmalloc (offsetof (struct string, s) + len);

      s = (struct string *) *slot;

      s->next = NULL;
      s->hash = hash;
      s->offset = strings->strings_len;
      s->source_file_offset = 0xffffffff;
      s->len = len;
      memcpy (s->s, str, len);

      if (strings->strings_tail)
	strings->strings_tail->next = s;
      else
	strings->strings_head = s;

      strings->strings_tail = s;

      strings->strings_len += len + 1;
    }
  else
    {
      s = (struct string *) *slot;
    }

  return s->offset;
}

/* Return the hash of an entry in the string table.  */
static hashval_t
hash_string_table_entry (const void *p)
{
  const struct string *s = (const struct string *) p;

  return s->hash;
}

/* Compare an entry in the string table with a string.  */
static int
eq_string_table_entry (const void *a, const void *b)
{
  const struct string *s1 = (const struct string *) a;
  const char *s2 = (const char *) b;
  size_t s2_len = strlen (s2);

  if (s2_len != s1->len)
    return 0;

  return memcmp (s1->s, s2, s2_len) == 0;
}

/* Parse the string table within the .debug$S section.  */
static void
parse_string_table (bfd_byte *data, size_t size,
		    struct string_table *strings)
{
  while (true)
    {
      size_t len = strnlen ((char *) data, size);

      add_string ((char *) data, len, strings);

      data += len + 1;

      if (size <= len + 1)
	break;

      size -= len + 1;
    }
}

/* Remap a type reference within a CodeView symbol.  */
static bool
remap_symbol_type (void *data, struct type_entry **map, uint32_t num_types)
{
  uint32_t type = bfd_getl32 (data);

  /* Ignore builtin types (those with IDs below 0x1000).  */
  if (type < TPI_FIRST_INDEX)
    return true;

  if (type >= TPI_FIRST_INDEX + num_types)
    {
      einfo (_("%P: CodeView symbol references out of range type %v\n"),
	       type);
      return false;
    }

  type = TPI_FIRST_INDEX + map[type - TPI_FIRST_INDEX]->index;
  bfd_putl32 (type, data);

  return true;
}

/* Add an entry into the globals stream.  If it already exists, increase
   the refcount.  */
static bool
add_globals_ref (struct globals *glob, bfd *sym_rec_stream, const char *name,
		 size_t name_len, uint8_t *data, size_t len)
{
  void **slot;
  uint32_t hash;
  struct global *g;

  slot = htab_find_slot_with_hash (glob->hashmap, data,
				   iterative_hash (data, len, 0), INSERT);

  if (*slot)
    {
      g = *slot;
      g->refcount++;
      return true;
    }

  *slot = xmalloc (offsetof (struct global, data) + len);

  hash = calc_hash (name, name_len);
  hash %= NUM_GLOBALS_HASH_BUCKETS;

  g = *slot;
  g->next = NULL;
  g->offset = bfd_tell (sym_rec_stream);
  g->hash = hash;
  g->refcount = 1;
  memcpy (g->data, data, len);

  glob->num_entries++;

  if (glob->last)
    glob->last->next = g;
  else
    glob->first = g;

  glob->last = g;

  return bfd_write (data, len, sym_rec_stream) == len;
}

/* Find the end of the current scope within symbols data.  */
static uint8_t *
find_end_of_scope (uint8_t *data, uint32_t size)
{
  unsigned int scope_level = 1;
  uint16_t len;

  len = bfd_getl16 (data) + sizeof (uint16_t);

  data += len;
  size -= len;

  while (true)
    {
      uint16_t type;

      if (size < sizeof (uint32_t))
	return NULL;

      len = bfd_getl16 (data) + sizeof (uint16_t);
      type = bfd_getl16 (data + sizeof (uint16_t));

      if (size < len)
	return NULL;

      switch (type)
	{
	case S_GPROC32:
	case S_LPROC32:
	case S_BLOCK32:
	case S_INLINESITE:
	case S_THUNK32:
	  scope_level++;
	  break;

	case S_END:
	case S_PROC_ID_END:
	case S_INLINESITE_END:
	  scope_level--;

	  if (scope_level == 0)
	    return data;

	  break;
	}

      data += len;
      size -= len;
    }
}

/* Return the size of an extended value parameter, as used in
   LF_ENUMERATE etc.  */
static unsigned int
extended_value_len (uint16_t type)
{
  switch (type)
    {
    case LF_CHAR:
      return 1;

    case LF_SHORT:
    case LF_USHORT:
      return 2;

    case LF_LONG:
    case LF_ULONG:
      return 4;

    case LF_QUADWORD:
    case LF_UQUADWORD:
      return 8;
    }

  return 0;
}

/* Parse the symbols in a .debug$S section, and copy them to the module's
   symbol stream.  */
static bool
parse_symbols (uint8_t *data, uint32_t size, uint8_t **buf,
	       struct type_entry **map, uint32_t num_types,
	       bfd *sym_rec_stream, struct globals *glob, uint16_t mod_num)
{
  uint8_t *orig_buf = *buf;
  unsigned int scope_level = 0;
  uint8_t *scope = NULL;

  while (size >= sizeof (uint16_t))
    {
      uint16_t len, type;

      len = bfd_getl16 (data) + sizeof (uint16_t);

      if (len > size)
	{
	  bfd_set_error (bfd_error_bad_value);
	  return false;
	}

      type = bfd_getl16 (data + sizeof (uint16_t));

      switch (type)
	{
	case S_LDATA32:
	case S_GDATA32:
	case S_LTHREAD32:
	case S_GTHREAD32:
	  {
	    struct datasym *d = (struct datasym *) data;
	    size_t name_len;

	    if (len < offsetof (struct datasym, name))
	      {
		einfo (_("%P: warning: truncated CodeView record"
			 " S_LDATA32/S_GDATA32/S_LTHREAD32/S_GTHREAD32\n"));
		bfd_set_error (bfd_error_bad_value);
		return false;
	      }

	    if (scope_level == 0)
	      {
		uint16_t section = bfd_getl16 (&d->section);

		if (section == 0) /* GC'd, ignore */
		  break;
	      }

	    name_len =
	      strnlen (d->name, len - offsetof (struct datasym, name));

	    if (name_len == len - offsetof (struct datasym, name))
	      {
		einfo (_("%P: warning: name for S_LDATA32/S_GDATA32/"
			 "S_LTHREAD32/S_GTHREAD32 has no terminating"
			 " zero\n"));
		bfd_set_error (bfd_error_bad_value);
		return false;
	      }

	    if (!remap_symbol_type (&d->type, map, num_types))
	      {
		bfd_set_error (bfd_error_bad_value);
		return false;
	      }

	    /* If S_LDATA32 or S_LTHREAD32, copy into module symbols.  */

	    if (type == S_LDATA32 || type == S_LTHREAD32)
	      {
		memcpy (*buf, d, len);
		*buf += len;
	      }

	    /* S_LDATA32 and S_LTHREAD32 only go in globals if
	       not in function scope.  */
	    if (type == S_GDATA32 || type == S_GTHREAD32 || scope_level == 0)
	      {
		if (!add_globals_ref (glob, sym_rec_stream, d->name,
				      name_len, data, len))
		  return false;
	      }

	    break;
	  }

	case S_GPROC32:
	case S_LPROC32:
	case S_GPROC32_ID:
	case S_LPROC32_ID:
	  {
	    struct procsym *proc = (struct procsym *) data;
	    size_t name_len;
	    uint16_t section;
	    uint32_t end;
	    uint8_t *endptr;
	    size_t ref_size, padding;
	    struct refsym *ref;

	    if (len < offsetof (struct procsym, name))
	      {
		einfo (_("%P: warning: truncated CodeView record"
			 " S_GPROC32/S_LPROC32\n"));
		bfd_set_error (bfd_error_bad_value);
		return false;
	      }

	    section = bfd_getl16 (&proc->section);

	    endptr = find_end_of_scope (data, size);

	    if (!endptr)
	      {
		einfo (_("%P: warning: could not find end of"
			 " S_GPROC32/S_LPROC32 record\n"));
		bfd_set_error (bfd_error_bad_value);
		return false;
	      }

	    if (section == 0) /* skip if GC'd */
	      {
		/* Skip to after S_END.  */

		size -= endptr - data;
		data = endptr;

		len = bfd_getl16 (data) + sizeof (uint16_t);

		data += len;
		size -= len;

		continue;
	      }

	    name_len =
	      strnlen (proc->name, len - offsetof (struct procsym, name));

	    if (name_len == len - offsetof (struct procsym, name))
	      {
		einfo (_("%P: warning: name for S_GPROC32/S_LPROC32 has no"
			 " terminating zero\n"));
		bfd_set_error (bfd_error_bad_value);
		return false;
	      }

	    if (type == S_GPROC32_ID || type == S_LPROC32_ID)
	      {
		/* Transform into S_GPROC32 / S_LPROC32.  */

		uint32_t t_idx = bfd_getl32 (&proc->type);
		struct type_entry *t;
		uint16_t t_type;

		if (t_idx < TPI_FIRST_INDEX
		    || t_idx >= TPI_FIRST_INDEX + num_types)
		  {
		    einfo (_("%P: CodeView symbol references out of range"
			     " type %v\n"), type);
		    bfd_set_error (bfd_error_bad_value);
		    return false;
		  }

		t = map[t_idx - TPI_FIRST_INDEX];

		t_type = bfd_getl16 (t->data + sizeof (uint16_t));

		switch (t_type)
		  {
		  case LF_FUNC_ID:
		    {
		      struct lf_func_id *t_data =
			(struct lf_func_id *) t->data;

		      /* Replace proc->type with function type.  */

		      memcpy (&proc->type, &t_data->function_type,
			      sizeof (uint32_t));

		      break;
		    }

		  case LF_MFUNC_ID:
		    {
		      struct lf_mfunc_id *t_data =
			(struct lf_mfunc_id *) t->data;

		      /* Replace proc->type with function type.  */

		      memcpy (&proc->type, &t_data->function_type,
			      sizeof (uint32_t));

		      break;
		    }

		  default:
		    einfo (_("%P: CodeView S_GPROC32_ID/S_LPROC32_ID symbol"
			     " referenced unknown type as ID\n"));
		    bfd_set_error (bfd_error_bad_value);
		    return false;
		  }

		/* Change record type.  */

		if (type == S_GPROC32_ID)
		  bfd_putl32 (S_GPROC32, &proc->kind);
		else
		  bfd_putl32 (S_LPROC32, &proc->kind);
	      }
	    else
	      {
		if (!remap_symbol_type (&proc->type, map, num_types))
		  {
		    bfd_set_error (bfd_error_bad_value);
		    return false;
		  }
	      }

	    end = *buf - orig_buf + sizeof (uint32_t) + endptr - data;
	    bfd_putl32 (end, &proc->end);

	    /* Add S_PROCREF / S_LPROCREF to globals stream.  */

	    ref_size = offsetof (struct refsym, name) + name_len + 1;

	    if (ref_size % sizeof (uint32_t))
	      padding = sizeof (uint32_t) - (ref_size % sizeof (uint32_t));
	    else
	      padding = 0;

	    ref = xmalloc (ref_size + padding);

	    bfd_putl16 (ref_size + padding - sizeof (uint16_t), &ref->size);
	    bfd_putl16 (type == S_GPROC32 || type == S_GPROC32_ID ?
			S_PROCREF : S_LPROCREF, &ref->kind);
	    bfd_putl32 (0, &ref->sum_name);
	    bfd_putl32 (*buf - orig_buf + sizeof (uint32_t),
			&ref->symbol_offset);
	    bfd_putl16 (mod_num + 1, &ref->mod);

	    memcpy (ref->name, proc->name, name_len + 1);

	    memset (ref->name + name_len + 1, 0, padding);

	    if (!add_globals_ref (glob, sym_rec_stream, proc->name, name_len,
				  (uint8_t *) ref, ref_size + padding))
	      {
		free (ref);
		return false;
	      }

	    free (ref);

	    scope = *buf;

	    memcpy (*buf, proc, len);
	    *buf += len;

	    scope_level++;

	    break;
	  }

	case S_UDT:
	  {
	    struct udtsym *udt = (struct udtsym *) data;
	    size_t name_len;

	    if (len < offsetof (struct udtsym, name))
	      {
		einfo (_("%P: warning: truncated CodeView record"
			 " S_UDT\n"));
		bfd_set_error (bfd_error_bad_value);
		return false;
	      }

	    name_len =
	      strnlen (udt->name, len - offsetof (struct udtsym, name));

	    if (name_len == len - offsetof (struct udtsym, name))
	      {
		einfo (_("%P: warning: name for S_UDT has no"
			 " terminating zero\n"));
		bfd_set_error (bfd_error_bad_value);
		return false;
	      }

	    if (!remap_symbol_type (&udt->type, map, num_types))
	      {
		bfd_set_error (bfd_error_bad_value);
		return false;
	      }

	    /* S_UDT goes in the symbols stream if within a procedure,
	       otherwise it goes in the globals stream.  */
	    if (scope_level == 0)
	      {
		if (!add_globals_ref (glob, sym_rec_stream, udt->name,
				      name_len, data, len))
		  return false;
	      }
	    else
	      {
		memcpy (*buf, udt, len);
		*buf += len;
	      }

	    break;
	  }

	case S_CONSTANT:
	  {
	    struct constsym *c = (struct constsym *) data;
	    size_t name_len, rec_size;
	    uint16_t val;

	    if (len < offsetof (struct constsym, name))
	      {
		einfo (_("%P: warning: truncated CodeView record"
			 " S_CONSTANT\n"));
		bfd_set_error (bfd_error_bad_value);
		return false;
	      }

	    rec_size = offsetof (struct constsym, name);

	    val = bfd_getl16 (&c->value);

	    /* If val >= 0x8000, actual value follows.  */
	    if (val >= 0x8000)
	      {
		unsigned int param_len = extended_value_len (val);

		if (param_len == 0)
		  {
		    einfo (_("%P: warning: unhandled type %v within"
			     " S_CONSTANT\n"), val);
		    bfd_set_error (bfd_error_bad_value);
		    return false;
		  }

		rec_size += param_len;
	      }

	    name_len =
	      strnlen ((const char *) data + rec_size, len - rec_size);

	    if (name_len == len - rec_size)
	      {
		einfo (_("%P: warning: name for S_CONSTANT has no"
			 " terminating zero\n"));
		bfd_set_error (bfd_error_bad_value);
		return false;
	      }

	    if (!remap_symbol_type (&c->type, map, num_types))
	      {
		bfd_set_error (bfd_error_bad_value);
		return false;
	      }

	    if (!add_globals_ref (glob, sym_rec_stream,
				  (const char *) data + rec_size, name_len,
				  data, len))
	      return false;

	    break;
	  }

	case S_END:
	case S_INLINESITE_END:
	case S_PROC_ID_END:
	  memcpy (*buf, data, len);

	  if (type == S_PROC_ID_END) /* transform to S_END */
	    bfd_putl16 (S_END, *buf + sizeof (uint16_t));

	  /* Reset scope variable back to the address of the previous
	     scope start.  */
	  if (scope)
	    {
	      uint32_t parent;
	      uint16_t scope_start_type =
		bfd_getl16 (scope + sizeof (uint16_t));

	      switch (scope_start_type)
		{
		case S_GPROC32:
		case S_LPROC32:
		  parent = bfd_getl32 (scope + offsetof (struct procsym,
							 parent));
		  break;

		case S_BLOCK32:
		  parent = bfd_getl32 (scope + offsetof (struct blocksym,
							 parent));
		  break;

		case S_INLINESITE:
		  parent = bfd_getl32 (scope + offsetof (struct inline_site,
							 parent));
		  break;

		case S_THUNK32:
		  parent = bfd_getl32 (scope + offsetof (struct thunk,
							 parent));
		  break;

		default:
		  einfo (_("%P: warning: unexpected CodeView scope start"
			   " record %v\n"), scope_start_type);
		  bfd_set_error (bfd_error_bad_value);
		  return false;
		}

	      if (parent == 0)
		scope = NULL;
	      else
		scope = orig_buf + parent - sizeof (uint32_t);
	    }

	  *buf += len;
	  scope_level--;
	  break;

	case S_BUILDINFO:
	  {
	    struct buildinfosym *bi = (struct buildinfosym *) data;

	    if (len < sizeof (struct buildinfosym))
	      {
		einfo (_("%P: warning: truncated CodeView record"
			 " S_BUILDINFO\n"));
		bfd_set_error (bfd_error_bad_value);
		return false;
	      }

	    if (!remap_symbol_type (&bi->type, map, num_types))
	      {
		bfd_set_error (bfd_error_bad_value);
		return false;
	      }

	    memcpy (*buf, data, len);
	    *buf += len;

	    break;
	  }

	case S_BLOCK32:
	  {
	    struct blocksym *bl = (struct blocksym *) data;
	    uint8_t *endptr;
	    uint32_t end;

	    if (len < offsetof (struct blocksym, name))
	      {
		einfo (_("%P: warning: truncated CodeView record"
			 " S_BLOCK32\n"));
		bfd_set_error (bfd_error_bad_value);
		return false;
	      }

	    bfd_putl32 (scope - orig_buf + sizeof (uint32_t), &bl->parent);

	    endptr = find_end_of_scope (data, size);

	    if (!endptr)
	      {
		einfo (_("%P: warning: could not find end of"
			 " S_BLOCK32 record\n"));
		bfd_set_error (bfd_error_bad_value);
		return false;
	      }

	    end = *buf - orig_buf + sizeof (uint32_t) + endptr - data;
	    bfd_putl32 (end, &bl->end);

	    scope = *buf;

	    memcpy (*buf, data, len);
	    *buf += len;

	    scope_level++;

	    break;
	  }

	case S_BPREL32:
	  {
	    struct bprelsym *bp = (struct bprelsym *) data;

	    if (len < offsetof (struct bprelsym, name))
	      {
		einfo (_("%P: warning: truncated CodeView record"
			 " S_BPREL32\n"));
		bfd_set_error (bfd_error_bad_value);
		return false;
	      }

	    if (!remap_symbol_type (&bp->type, map, num_types))
	      {
		bfd_set_error (bfd_error_bad_value);
		return false;
	      }

	    memcpy (*buf, data, len);
	    *buf += len;

	    break;
	  }

	case S_REGISTER:
	  {
	    struct regsym *reg = (struct regsym *) data;

	    if (len < offsetof (struct regsym, name))
	      {
		einfo (_("%P: warning: truncated CodeView record"
			 " S_REGISTER\n"));
		bfd_set_error (bfd_error_bad_value);
		return false;
	      }

	    if (!remap_symbol_type (&reg->type, map, num_types))
	      {
		bfd_set_error (bfd_error_bad_value);
		return false;
	      }

	    memcpy (*buf, data, len);
	    *buf += len;

	    break;
	  }

	case S_REGREL32:
	  {
	    struct regrel *rr = (struct regrel *) data;

	    if (len < offsetof (struct regrel, name))
	      {
		einfo (_("%P: warning: truncated CodeView record"
			 " S_REGREL32\n"));
		bfd_set_error (bfd_error_bad_value);
		return false;
	      }

	    if (!remap_symbol_type (&rr->type, map, num_types))
	      {
		bfd_set_error (bfd_error_bad_value);
		return false;
	      }

	    memcpy (*buf, data, len);
	    *buf += len;

	    break;
	  }

	case S_LOCAL:
	  {
	    struct localsym *l = (struct localsym *) data;

	    if (len < offsetof (struct localsym, name))
	      {
		einfo (_("%P: warning: truncated CodeView record"
			 " S_LOCAL\n"));
		bfd_set_error (bfd_error_bad_value);
		return false;
	      }

	    if (!remap_symbol_type (&l->type, map, num_types))
	      {
		bfd_set_error (bfd_error_bad_value);
		return false;
	      }

	    memcpy (*buf, data, len);
	    *buf += len;

	    break;
	  }

	case S_INLINESITE:
	  {
	    struct inline_site *is = (struct inline_site *) data;
	    uint8_t *endptr;
	    uint32_t end;

	    if (len < offsetof (struct inline_site, binary_annotations))
	      {
		einfo (_("%P: warning: truncated CodeView record"
			 " S_INLINESITE\n"));
		bfd_set_error (bfd_error_bad_value);
		return false;
	      }

	    bfd_putl32 (scope - orig_buf + sizeof (uint32_t), &is->parent);

	    endptr = find_end_of_scope (data, size);

	    if (!endptr)
	      {
		einfo (_("%P: warning: could not find end of"
			 " S_INLINESITE record\n"));
		bfd_set_error (bfd_error_bad_value);
		return false;
	      }

	    end = *buf - orig_buf + sizeof (uint32_t) + endptr - data;
	    bfd_putl32 (end, &is->end);

	    if (!remap_symbol_type (&is->inlinee, map, num_types))
	      {
		bfd_set_error (bfd_error_bad_value);
		return false;
	      }

	    scope = *buf;

	    memcpy (*buf, data, len);
	    *buf += len;

	    scope_level++;

	    break;
	  }

	case S_THUNK32:
	  {
	    struct thunk *th = (struct thunk *) data;
	    uint8_t *endptr;
	    uint32_t end;

	    if (len < offsetof (struct thunk, name))
	      {
		einfo (_("%P: warning: truncated CodeView record"
			 " S_THUNK32\n"));
		bfd_set_error (bfd_error_bad_value);
		return false;
	      }

	    bfd_putl32 (scope - orig_buf + sizeof (uint32_t), &th->parent);

	    endptr = find_end_of_scope (data, size);

	    if (!endptr)
	      {
		einfo (_("%P: warning: could not find end of"
			 " S_THUNK32 record\n"));
		bfd_set_error (bfd_error_bad_value);
		return false;
	      }

	    end = *buf - orig_buf + sizeof (uint32_t) + endptr - data;
	    bfd_putl32 (end, &th->end);

	    scope = *buf;

	    memcpy (*buf, data, len);
	    *buf += len;

	    scope_level++;

	    break;
	  }

	case S_HEAPALLOCSITE:
	  {
	    struct heap_alloc_site *has = (struct heap_alloc_site *) data;

	    if (len < sizeof (struct heap_alloc_site))
	      {
		einfo (_("%P: warning: truncated CodeView record"
			 " S_HEAPALLOCSITE\n"));
		bfd_set_error (bfd_error_bad_value);
		return false;
	      }

	    if (!remap_symbol_type (&has->type, map, num_types))
	      {
		bfd_set_error (bfd_error_bad_value);
		return false;
	      }

	    memcpy (*buf, data, len);
	    *buf += len;

	    break;
	  }

	case S_OBJNAME: /* just copy */
	case S_COMPILE3:
	case S_UNAMESPACE:
	case S_FRAMEPROC:
	case S_FRAMECOOKIE:
	case S_LABEL32:
	case S_DEFRANGE_REGISTER_REL:
	case S_DEFRANGE_FRAMEPOINTER_REL:
	case S_DEFRANGE_SUBFIELD_REGISTER:
	case S_DEFRANGE_FRAMEPOINTER_REL_FULL_SCOPE:
	case S_DEFRANGE_REGISTER:
	  memcpy (*buf, data, len);
	  *buf += len;
	  break;

	default:
	  einfo (_("%P: warning: unrecognized CodeView record %v\n"), type);
	  bfd_set_error (bfd_error_bad_value);
	  return false;
	}

      data += len;
      size -= len;
    }

  return true;
}

/* For a given symbol subsection, work out how much space to allocate in the
   result module stream.  This is different because we don't copy certain
   symbols, such as S_CONSTANT, and we skip over any procedures or data that
   have been GC'd out.  */
static bool
calculate_symbols_size (uint8_t *data, uint32_t size, uint32_t *sym_size)
{
  unsigned int scope_level = 0;

  while (size >= sizeof (uint32_t))
    {
      uint16_t len = bfd_getl16 (data) + sizeof (uint16_t);
      uint16_t type = bfd_getl16 (data + sizeof (uint16_t));

      switch (type)
	{
	case S_LDATA32:
	case S_LTHREAD32:
	  {
	    struct datasym *d = (struct datasym *) data;
	    uint16_t section;

	    if (len < offsetof (struct datasym, name))
	      {
		einfo (_("%P: warning: truncated CodeView record"
			 " S_LDATA32/S_LTHREAD32\n"));
		return false;
	      }

	    section = bfd_getl16 (&d->section);

	    /* copy if not GC'd or within function */
	    if (scope_level != 0 || section != 0)
	      *sym_size += len;
	  }

	case S_GDATA32:
	case S_GTHREAD32:
	case S_CONSTANT:
	  /* Not copied into symbols stream.  */
	  break;

	case S_GPROC32:
	case S_LPROC32:
	case S_GPROC32_ID:
	case S_LPROC32_ID:
	  {
	    struct procsym *proc = (struct procsym *) data;
	    uint16_t section;

	    if (len < offsetof (struct procsym, name))
	      {
		einfo (_("%P: warning: truncated CodeView record"
			 " S_GPROC32/S_LPROC32\n"));
		return false;
	      }

	    section = bfd_getl16 (&proc->section);

	    if (section != 0)
	      {
		*sym_size += len;
	      }
	    else
	      {
		uint8_t *endptr = find_end_of_scope (data, size);

		if (!endptr)
		  {
		    einfo (_("%P: warning: could not find end of"
			     " S_GPROC32/S_LPROC32 record\n"));
		    return false;
		  }

		/* Skip to after S_END.  */

		size -= endptr - data;
		data = endptr;

		len = bfd_getl16 (data) + sizeof (uint16_t);

		data += len;
		size -= len;

		continue;
	      }

	    scope_level++;

	    break;
	  }

	case S_UDT:
	  if (scope_level != 0) /* only goes in symbols if local */
	    *sym_size += len;
	  break;

	case S_BLOCK32: /* always copied */
	case S_INLINESITE:
	case S_THUNK32:
	  *sym_size += len;
	  scope_level++;
	  break;

	case S_END: /* always copied */
	case S_PROC_ID_END:
	case S_INLINESITE_END:
	  *sym_size += len;
	  scope_level--;
	  break;

	case S_OBJNAME: /* always copied */
	case S_COMPILE3:
	case S_UNAMESPACE:
	case S_FRAMEPROC:
	case S_FRAMECOOKIE:
	case S_LABEL32:
	case S_BUILDINFO:
	case S_BPREL32:
	case S_REGISTER:
	case S_REGREL32:
	case S_LOCAL:
	case S_DEFRANGE_REGISTER_REL:
	case S_DEFRANGE_FRAMEPOINTER_REL:
	case S_DEFRANGE_SUBFIELD_REGISTER:
	case S_DEFRANGE_FRAMEPOINTER_REL_FULL_SCOPE:
	case S_DEFRANGE_REGISTER:
	case S_HEAPALLOCSITE:
	  *sym_size += len;
	  break;

	default:
	  einfo (_("%P: warning: unrecognized CodeView record %v\n"), type);
	  return false;
	}

      data += len;
      size -= len;
    }

  return true;
}

/* Parse the .debug$S section within an object file.  */
static bool
handle_debugs_section (asection *s, bfd *mod, struct string_table *strings,
		       uint8_t **dataptr, uint32_t *sizeptr,
		       struct mod_source_files *mod_source,
		       bfd *abfd, uint8_t **syms, uint32_t *sym_byte_size,
		       struct type_entry **map, uint32_t num_types,
		       bfd *sym_rec_stream, struct globals *glob,
		       uint16_t mod_num)
{
  bfd_byte *data = NULL;
  size_t off;
  uint32_t c13_size = 0;
  char *string_table = NULL;
  uint8_t *buf, *bufptr, *symbuf, *symbufptr;
  uint32_t sym_size = 0;

  if (!bfd_get_full_section_contents (mod, s, &data))
    return false;

  if (!data)
    return false;

  /* Resolve relocations.  Addresses are stored within the .debug$S section as
     a .secidx, .secrel32 pair.  */

  if (s->flags & SEC_RELOC)
    {
      struct internal_reloc *relocs;
      struct internal_syment *symbols;
      asection **sectlist;
      unsigned int syment_count;
      int sect_num;
      struct external_syment *ext;

      syment_count = obj_raw_syment_count (mod);

      relocs =
	_bfd_coff_read_internal_relocs (mod, s, false, NULL, true, NULL);

      symbols = xmalloc (sizeof (struct internal_syment) * syment_count);
      sectlist = xmalloc (sizeof (asection *) * syment_count);

      ext = (struct external_syment *) (coff_data (mod)->external_syms);

      for (unsigned int i = 0; i < syment_count; i++)
	{
	  bfd_coff_swap_sym_in (mod, &ext[i], &symbols[i]);
	}

      sect_num = 1;

      for (asection *sect = mod->sections; sect; sect = sect->next)
	{
	  for (unsigned int i = 0; i < syment_count; i++)
	    {
	      if (symbols[i].n_scnum == sect_num)
		sectlist[i] = sect;
	    }

	  sect_num++;
	}

      if (!bfd_coff_relocate_section (abfd, coff_data (abfd)->link_info, mod,
				      s, data, relocs, symbols, sectlist))
	{
	  free (sectlist);
	  free (symbols);
	  free (data);
	  return false;
	}

      free (sectlist);
      free (symbols);
    }

  if (bfd_getl32 (data) != CV_SIGNATURE_C13)
    {
      free (data);
      return true;
    }

  off = sizeof (uint32_t);

  /* calculate size */

  while (off + sizeof (uint32_t) <= s->size)
    {
      uint32_t type, size;

      type = bfd_getl32 (data + off);

      off += sizeof (uint32_t);

      if (off + sizeof (uint32_t) > s->size)
	{
	  free (data);
	  bfd_set_error (bfd_error_bad_value);
	  return false;
	}

      size = bfd_getl32 (data + off);

      off += sizeof (uint32_t);

      if (off + size > s->size)
	{
	  free (data);
	  bfd_set_error (bfd_error_bad_value);
	  return false;
	}

      switch (type)
	{
	case DEBUG_S_FILECHKSMS:
	  c13_size += sizeof (uint32_t) + sizeof (uint32_t) + size;

	  if (c13_size % sizeof (uint32_t))
	    c13_size += sizeof (uint32_t) - (c13_size % sizeof (uint32_t));

	  break;

	case DEBUG_S_STRINGTABLE:
	  parse_string_table (data + off, size, strings);

	  string_table = (char *) data + off;

	  break;

	case DEBUG_S_LINES:
	  {
	    uint16_t sect;

	    if (size < sizeof (uint32_t) + sizeof (uint16_t))
	      {
		free (data);
		bfd_set_error (bfd_error_bad_value);
		return false;
	      }

	    sect = bfd_getl16 (data + off + sizeof (uint32_t));

	    /* Skip GC'd symbols.  */
	    if (sect != 0)
	      {
		c13_size += sizeof (uint32_t) + sizeof (uint32_t) + size;

		if (c13_size % sizeof (uint32_t))
		  c13_size +=
		    sizeof (uint32_t) - (c13_size % sizeof (uint32_t));
	      }

	    break;
	  }

	case DEBUG_S_SYMBOLS:
	  if (!calculate_symbols_size (data + off, size, &sym_size))
	    {
	      free (data);
	      bfd_set_error (bfd_error_bad_value);
	      return false;
	    }

	  break;
	}

      off += size;

      if (off % sizeof (uint32_t))
	off += sizeof (uint32_t) - (off % sizeof (uint32_t));
    }

  if (sym_size % sizeof (uint32_t))
    sym_size += sizeof (uint32_t) - (sym_size % sizeof (uint32_t));

  if (c13_size == 0 && sym_size == 0)
    {
      free (data);
      return true;
    }

  /* copy data */

  buf = NULL;
  if (c13_size != 0)
    buf = xmalloc (c13_size);
  bufptr = buf;

  symbuf = NULL;
  if (sym_size != 0)
    symbuf = xmalloc (sym_size);
  symbufptr = symbuf;

  off = sizeof (uint32_t);

  while (off + sizeof (uint32_t) <= s->size)
    {
      uint32_t type, size;

      type = bfd_getl32 (data + off);
      off += sizeof (uint32_t);

      size = bfd_getl32 (data + off);
      off += sizeof (uint32_t);

      switch (type)
	{
	case DEBUG_S_FILECHKSMS:
	  if (!copy_filechksms (data + off, size, string_table,
				strings, bufptr, mod_source))
	    {
	      free (data);
	      free (symbuf);
	      return false;
	    }

	  bufptr += sizeof (uint32_t) + sizeof (uint32_t) + size;

	  break;

	case DEBUG_S_LINES:
	  {
	    uint16_t sect;

	    sect = bfd_getl16 (data + off + sizeof (uint32_t));

	    /* Skip if GC'd.  */
	    if (sect != 0)
	      {
		bfd_putl32 (type, bufptr);
		bufptr += sizeof (uint32_t);

		bfd_putl32 (size, bufptr);
		bufptr += sizeof (uint32_t);

		memcpy (bufptr, data + off, size);
		bufptr += size;
	      }

	    break;
	  }

	case DEBUG_S_SYMBOLS:
	  if (!parse_symbols (data + off, size, &symbufptr, map, num_types,
			      sym_rec_stream, glob, mod_num))
	    {
	      free (data);
	      free (symbuf);
	      return false;
	    }

	  break;
	}

      off += size;

      if (off % sizeof (uint32_t))
	off += sizeof (uint32_t) - (off % sizeof (uint32_t));
    }

  free (data);

  if (buf)
    {
      if (*dataptr)
	{
	  /* Append the C13 info to what's already there, if the module has
	     multiple .debug$S sections.  */

	  *dataptr = xrealloc (*dataptr, *sizeptr + c13_size);
	  memcpy (*dataptr + *sizeptr, buf, c13_size);

	  free (buf);
	}
      else
	{
	  *dataptr = buf;
	}

      *sizeptr += c13_size;
    }

  if (symbuf)
    {
      if (*syms)
	{
	  *syms = xrealloc (*syms, *sym_byte_size + sym_size);
	  memcpy (*syms + *sym_byte_size, symbuf, sym_size);

	  free (symbuf);
	}
      else
	{
	  *syms = symbuf;
	}

      *sym_byte_size += sym_size;
    }

  return true;
}

/* Remap the type number stored in data from the per-module numbering to
   that of the deduplicated output list.  */
static bool
remap_type (void *data, struct type_entry **map,
	    uint32_t type_num, uint32_t num_types)
{
  uint32_t type = bfd_getl32 (data);

  /* Ignore builtin types (those with IDs below 0x1000).  */
  if (type < TPI_FIRST_INDEX)
    return true;

  if (type >= TPI_FIRST_INDEX + type_num)
    {
      einfo (_("%P: CodeView type %v references other type %v not yet "
	       "declared\n"), TPI_FIRST_INDEX + type_num, type);
      return false;
    }

  if (type >= TPI_FIRST_INDEX + num_types)
    {
      einfo (_("%P: CodeView type %v references out of range type %v\n"),
	     TPI_FIRST_INDEX + type_num, type);
      return false;
    }

  type = TPI_FIRST_INDEX + map[type - TPI_FIRST_INDEX]->index;
  bfd_putl32 (type, data);

  return true;
}

/* Determines whether the name of a struct, class, or union counts as
   "anonymous".  Non-anonymous types have a hash based on just the name,
   rather than the whole structure.  */
static bool
is_name_anonymous (char *name, size_t len)
{
  static const char tag1[] = "<unnamed-tag>";
  static const char tag2[] = "__unnamed";
  static const char tag3[] = "::<unnamed-tag>";
  static const char tag4[] = "::__unnamed";

  if (len == sizeof (tag1) - 1 && !memcmp (name, tag1, sizeof (tag1) - 1))
    return true;

  if (len == sizeof (tag2) - 1 && !memcmp (name, tag2, sizeof (tag2) - 1))
    return true;

  if (len >= sizeof (tag3) - 1
      && !memcmp (name + len - sizeof (tag3) + 1, tag3, sizeof (tag3) - 1))
    return true;

  if (len >= sizeof (tag4) - 1
      && !memcmp (name + len - sizeof (tag4) + 1, tag4, sizeof (tag4) - 1))
    return true;

  return false;
}

/* Handle LF_UDT_SRC_LINE type entries, which are a special case.  These
   give the source file and line number for each user-defined type that is
   declared.  We parse these and emit instead an LF_UDT_MOD_SRC_LINE entry,
   which also includes the module number.  */
static bool
handle_udt_src_line (uint8_t *data, uint16_t size, struct type_entry **map,
		     uint32_t type_num, uint32_t num_types,
		     struct types *ids, uint16_t mod_num,
		     struct string_table *strings)
{
  struct lf_udt_src_line *usl = (struct lf_udt_src_line *) data;
  uint32_t orig_type, source_file_type;
  void **slot;
  hashval_t hash;
  struct type_entry *e, *type_e, *str_e;
  struct lf_udt_mod_src_line *umsl;
  struct lf_string_id *str;
  uint32_t source_file_offset;

  if (size < sizeof (struct lf_udt_src_line))
    {
      einfo (_("%P: warning: truncated CodeView type record"
	       " LF_UDT_SRC_LINE\n"));
      return false;
    }

  /* Check if LF_UDT_MOD_SRC_LINE already present for type, and return.  */

  orig_type = bfd_getl32 (&usl->type);

  if (orig_type < TPI_FIRST_INDEX ||
      orig_type >= TPI_FIRST_INDEX + num_types ||
      !map[orig_type - TPI_FIRST_INDEX])
    {
      einfo (_("%P: warning: CodeView type record LF_UDT_SRC_LINE"
	       " referred to unknown type %v\n"), orig_type);
      return false;
    }

  type_e = map[orig_type - TPI_FIRST_INDEX];

  /* Skip if type already declared in other module.  */
  if (type_e->has_udt_src_line)
    return true;

  if (!remap_type (&usl->type, map, type_num, num_types))
    return false;

  /* Extract string from source_file_type.  */

  source_file_type = bfd_getl32 (&usl->source_file_type);

  if (source_file_type < TPI_FIRST_INDEX ||
      source_file_type >= TPI_FIRST_INDEX + num_types ||
      !map[source_file_type - TPI_FIRST_INDEX])
    {
      einfo (_("%P: warning: CodeView type record LF_UDT_SRC_LINE"
	       " referred to unknown string %v\n"), source_file_type);
      return false;
    }

  str_e = map[source_file_type - TPI_FIRST_INDEX];

  if (bfd_getl16 (str_e->data + sizeof (uint16_t)) != LF_STRING_ID)
    {
      einfo (_("%P: warning: CodeView type record LF_UDT_SRC_LINE"
	       " pointed to unexpected record type\n"));
      return false;
    }

  str = (struct lf_string_id *) str_e->data;

  /* Add string to string table.  */

  source_file_offset = add_string (str->string, strlen (str->string),
				   strings);

  /* Add LF_UDT_MOD_SRC_LINE entry.  */

  size = sizeof (struct lf_udt_mod_src_line);

  e = xmalloc (offsetof (struct type_entry, data) + size);

  e->next = NULL;
  e->index = ids->num_types;
  e->has_udt_src_line = false;

  /* LF_UDT_MOD_SRC_LINE use calc_hash on the type number, rather than
     the crc32 used for type hashes elsewhere.  */
  e->cv_hash = calc_hash ((char *) &usl->type, sizeof (uint32_t));

  type_e->has_udt_src_line = true;

  umsl = (struct lf_udt_mod_src_line *) e->data;

  bfd_putl16 (size - sizeof (uint16_t), &umsl->size);
  bfd_putl16 (LF_UDT_MOD_SRC_LINE, &umsl->kind);
  memcpy (&umsl->type, &usl->type, sizeof (uint32_t));
  bfd_putl32 (source_file_offset, &umsl->source_file_string);
  memcpy (&umsl->line_no, &usl->line_no, sizeof (uint32_t));
  bfd_putl16 (mod_num + 1, &umsl->module_no);

  hash = iterative_hash (e->data, size, 0);

  slot = htab_find_slot_with_hash (ids->hashmap, data, hash, INSERT);
  if (!slot)
    {
      free (e);
      return false;
    }

  if (*slot)
    {
      free (e);
      einfo (_("%P: warning: duplicate CodeView type record "
	       "LF_UDT_MOD_SRC_LINE\n"));
      return false;
    }

  *slot = e;

  if (ids->last)
    ids->last->next = e;
  else
    ids->first = e;

  ids->last = e;

  map[type_num] = e;

  ids->num_types++;

  return true;
}

/* Parse a type definition in the .debug$T section.  We remap the numbers
   of any referenced types, and if the type is not a duplicate of one
   already seen add it to types (for TPI types) or ids (for IPI types).  */
static bool
handle_type (uint8_t *data, struct type_entry **map, uint32_t type_num,
	     uint32_t num_types, struct types *types,
	     struct types *ids, uint16_t mod_num,
	     struct string_table *strings)
{
  uint16_t size, type;
  void **slot;
  hashval_t hash;
  bool other_hash = false;
  uint32_t cv_hash;
  struct types *t;
  bool ipi = false;

  size = bfd_getl16 (data) + sizeof (uint16_t);
  type = bfd_getl16 (data + sizeof (uint16_t));

  switch (type)
    {
    case LF_MODIFIER:
      {
	struct lf_modifier *mod = (struct lf_modifier *) data;

	if (size < offsetof (struct lf_modifier, modifier))
	  {
	    einfo (_("%P: warning: truncated CodeView type record "
		     "LF_MODIFIER\n"));
	    return false;
	  }

	if (!remap_type (&mod->base_type, map, type_num, num_types))
	  return false;

	break;
      }

    case LF_POINTER:
      {
	struct lf_pointer *ptr = (struct lf_pointer *) data;
	uint32_t attributes;

	if (size < offsetof (struct lf_pointer, attributes))
	  {
	    einfo (_("%P: warning: truncated CodeView type record"
		     " LF_POINTER\n"));
	    return false;
	  }

	if (!remap_type (&ptr->base_type, map, type_num, num_types))
	  return false;

	attributes = bfd_getl32 (&ptr->attributes);

	if ((attributes & CV_PTR_MODE_MASK) == CV_PTR_MODE_PMEM
	    || (attributes & CV_PTR_MODE_MASK) == CV_PTR_MODE_PMFUNC)
	  {
	    if (size < offsetof (struct lf_pointer, ptr_to_mem_type))
	      {
		einfo (_("%P: warning: truncated CodeView type record"
			 " LF_POINTER\n"));
		return false;
	      }

	    if (!remap_type (&ptr->containing_class, map, type_num, num_types))
	      return false;
	  }

	break;
      }

    case LF_PROCEDURE:
      {
	struct lf_procedure *proc = (struct lf_procedure *) data;

	if (size < sizeof (struct lf_procedure))
	  {
	    einfo (_("%P: warning: truncated CodeView type record"
		     " LF_PROCEDURE\n"));
	    return false;
	  }

	if (!remap_type (&proc->return_type, map, type_num, num_types))
	  return false;

	if (!remap_type (&proc->arglist, map, type_num, num_types))
	  return false;

	break;
      }

    case LF_MFUNCTION:
      {
	struct lf_mfunction *func = (struct lf_mfunction *) data;

	if (size < sizeof (struct lf_procedure))
	  {
	    einfo (_("%P: warning: truncated CodeView type record"
		     " LF_MFUNCTION\n"));
	    return false;
	  }

	if (!remap_type (&func->return_type, map, type_num, num_types))
	  return false;

	if (!remap_type (&func->containing_class_type, map, type_num,
			 num_types))
	  return false;

	if (!remap_type (&func->this_type, map, type_num, num_types))
	  return false;

	if (!remap_type (&func->arglist, map, type_num, num_types))
	  return false;

	break;
      }

    case LF_ARGLIST:
      {
	uint32_t num_entries;
	struct lf_arglist *al = (struct lf_arglist *) data;

	if (size < offsetof (struct lf_arglist, args))
	  {
	    einfo (_("%P: warning: truncated CodeView type record"
		     " LF_ARGLIST\n"));
	    return false;
	  }

	num_entries = bfd_getl32 (&al->num_entries);

	if (size < offsetof (struct lf_arglist, args)
		   + (num_entries * sizeof (uint32_t)))
	  {
	    einfo (_("%P: warning: truncated CodeView type record"
		     " LF_ARGLIST\n"));
	    return false;
	  }

	for (uint32_t i = 0; i < num_entries; i++)
	  {
	    if (!remap_type (&al->args[i], map, type_num, num_types))
	      return false;
	  }

	break;
      }

    case LF_FIELDLIST:
      {
	uint16_t left = size - sizeof (uint16_t) - sizeof (uint16_t);
	uint8_t *ptr = data + sizeof (uint16_t) + sizeof (uint16_t);

	while (left > 0)
	  {
	    uint16_t subtype;

	    if (left < sizeof (uint16_t))
	      {
		einfo (_("%P: warning: truncated CodeView type record"
			 " LF_FIELDLIST\n"));
		return false;
	      }

	    subtype = bfd_getl16 (ptr);

	    switch (subtype)
	      {
	      case LF_MEMBER:
		{
		  struct lf_member *mem = (struct lf_member *) ptr;
		  uint16_t offset;
		  size_t name_len, subtype_len;

		  if (left < offsetof (struct lf_member, name))
		    {
		      einfo (_("%P: warning: truncated CodeView type record"
			       " LF_MEMBER\n"));
		      return false;
		    }

		  if (!remap_type (&mem->type, map, type_num, num_types))
		    return false;

		  subtype_len = offsetof (struct lf_member, name);

		  offset = bfd_getl16 (&mem->offset);

		  /* If offset >= 0x8000, actual value follows.  */
		  if (offset >= 0x8000)
		    {
		      unsigned int param_len = extended_value_len (offset);

		      if (param_len == 0)
			{
			  einfo (_("%P: warning: unhandled type %v within"
				   " LF_MEMBER\n"), offset);
			  return false;
			}

		      subtype_len += param_len;

		      if (left < subtype_len)
			{
			  einfo (_("%P: warning: truncated CodeView type record"
				  " LF_MEMBER\n"));
			  return false;
			}
		    }

		  name_len =
		    strnlen ((char *) mem + subtype_len, left - subtype_len);

		  if (name_len == left - offsetof (struct lf_member, name))
		    {
		      einfo (_("%P: warning: name for LF_MEMBER has no"
			       " terminating zero\n"));
		      return false;
		    }

		  name_len++;

		  subtype_len += name_len;

		  if (subtype_len % 4 != 0)
		    subtype_len += 4 - (subtype_len % 4);

		  if (left < subtype_len)
		    {
		      einfo (_("%P: warning: truncated CodeView type record"
			       " LF_FIELDLIST\n"));
		      return false;
		    }

		  ptr += subtype_len;
		  left -= subtype_len;

		  break;
		}

	      case LF_ENUMERATE:
		{
		  struct lf_enumerate *en = (struct lf_enumerate *) ptr;
		  size_t name_len, subtype_len;
		  uint16_t val;

		  if (left < offsetof (struct lf_enumerate, name))
		    {
		      einfo (_("%P: warning: truncated CodeView type record"
			       " LF_ENUMERATE\n"));
		      return false;
		    }

		  subtype_len = offsetof (struct lf_enumerate, name);

		  val = bfd_getl16 (&en->value);

		  /* If val >= 0x8000, the actual value immediately follows.  */
		  if (val >= 0x8000)
		    {
		      unsigned int param_len = extended_value_len (val);

		      if (param_len == 0)
			{
			  einfo (_("%P: warning: unhandled type %v within"
				   " LF_ENUMERATE\n"), val);
			  return false;
			}

		      if (left < subtype_len + param_len)
			{
			  einfo (_("%P: warning: truncated CodeView type"
				   " record LF_ENUMERATE\n"));
			  return false;
			}

		      subtype_len += param_len;
		    }

		  name_len = strnlen ((char *) ptr + subtype_len,
				      left - subtype_len);

		  if (name_len == left - offsetof (struct lf_enumerate, name))
		    {
		      einfo (_("%P: warning: name for LF_ENUMERATE has no"
			       " terminating zero\n"));
		      return false;
		    }

		  name_len++;

		  subtype_len += name_len;

		  if (subtype_len % 4 != 0)
		    subtype_len += 4 - (subtype_len % 4);

		  if (left < subtype_len)
		    {
		      einfo (_("%P: warning: truncated CodeView type record"
			       " LF_ENUMERATE\n"));
		      return false;
		    }

		  ptr += subtype_len;
		  left -= subtype_len;

		  break;
		}

	      case LF_INDEX:
		{
		  struct lf_index *ind = (struct lf_index *) ptr;

		  if (left < sizeof (struct lf_index))
		    {
		      einfo (_("%P: warning: truncated CodeView type record"
			       " LF_INDEX\n"));
		      return false;
		    }

		  if (!remap_type (&ind->index, map, type_num, num_types))
		    return false;

		  ptr += sizeof (struct lf_index);
		  left -= sizeof (struct lf_index);

		  break;
		}

	      case LF_ONEMETHOD:
		{
		  struct lf_onemethod *meth = (struct lf_onemethod *) ptr;
		  size_t name_len, subtype_len;

		  if (left < offsetof (struct lf_onemethod, name))
		    {
		      einfo (_("%P: warning: truncated CodeView type record"
			       " LF_ONEMETHOD\n"));
		      return false;
		    }

		  if (!remap_type (&meth->method_type, map, type_num,
				   num_types))
		    return false;

		  name_len =
		    strnlen (meth->name,
			     left - offsetof (struct lf_onemethod, name));

		  if (name_len == left - offsetof (struct lf_onemethod, name))
		    {
		      einfo (_("%P: warning: name for LF_ONEMETHOD has no"
			       " terminating zero\n"));
		      return false;
		    }

		  name_len++;

		  subtype_len = offsetof (struct lf_onemethod, name)
				+ name_len;

		  if (subtype_len % 4 != 0)
		    subtype_len += 4 - (subtype_len % 4);

		  if (left < subtype_len)
		    {
		      einfo (_("%P: warning: truncated CodeView type record"
			       " LF_FIELDLIST\n"));
		      return false;
		    }

		  ptr += subtype_len;
		  left -= subtype_len;

		  break;
		}

	      case LF_METHOD:
		{
		  struct lf_method *meth = (struct lf_method *) ptr;
		  size_t name_len, subtype_len;

		  if (left < offsetof (struct lf_method, name))
		    {
		      einfo (_("%P: warning: truncated CodeView type record"
			       " LF_METHOD\n"));
		      return false;
		    }

		  if (!remap_type (&meth->method_list, map, type_num,
				   num_types))
		    return false;

		  name_len =
		    strnlen (meth->name,
			     left - offsetof (struct lf_method, name));

		  if (name_len == left - offsetof (struct lf_method, name))
		    {
		      einfo (_("%P: warning: name for LF_METHOD has no"
			       " terminating zero\n"));
		      return false;
		    }

		  name_len++;

		  subtype_len = offsetof (struct lf_method, name) + name_len;

		  if (subtype_len % 4 != 0)
		    subtype_len += 4 - (subtype_len % 4);

		  if (left < subtype_len)
		    {
		      einfo (_("%P: warning: truncated CodeView type record"
			       " LF_FIELDLIST\n"));
		      return false;
		    }

		  ptr += subtype_len;
		  left -= subtype_len;

		  break;
		}

	      case LF_BCLASS:
		{
		  struct lf_bclass *bc = (struct lf_bclass *) ptr;
		  size_t subtype_len;
		  uint16_t offset;

		  if (left < sizeof (struct lf_bclass))
		    {
		      einfo (_("%P: warning: truncated CodeView type record"
			       " LF_BCLASS\n"));
		      return false;
		    }

		  if (!remap_type (&bc->base_class_type, map, type_num,
				   num_types))
		    return false;

		  subtype_len = sizeof (struct lf_bclass);

		  offset = bfd_getl16 (&bc->offset);

		  /* If offset >= 0x8000, actual value follows.  */
		  if (offset >= 0x8000)
		    {
		      unsigned int param_len = extended_value_len (offset);

		      if (param_len == 0)
			{
			  einfo (_("%P: warning: unhandled type %v within"
				   " LF_BCLASS\n"), offset);
			  return false;
			}

		      subtype_len += param_len;

		      if (left < subtype_len)
			{
			  einfo (_("%P: warning: truncated CodeView type record"
				   " LF_BCLASS\n"));
			  return false;
			}
		    }

		  if (subtype_len % 4 != 0)
		    subtype_len += 4 - (subtype_len % 4);

		  if (left < subtype_len)
		    {
		      einfo (_("%P: warning: truncated CodeView type record"
			       " LF_BCLASS\n"));
		      return false;
		    }

		  ptr += subtype_len;
		  left -= subtype_len;

		  break;
		}

	      case LF_VFUNCTAB:
		{
		  struct lf_vfunctab *vft = (struct lf_vfunctab *) ptr;

		  if (left < sizeof (struct lf_vfunctab))
		    {
		      einfo (_("%P: warning: truncated CodeView type record"
			       " LF_VFUNCTAB\n"));
		      return false;
		    }

		  if (!remap_type (&vft->type, map, type_num, num_types))
		    return false;

		  ptr += sizeof (struct lf_vfunctab);
		  left -= sizeof (struct lf_vfunctab);

		  break;
		}

	      case LF_VBCLASS:
	      case LF_IVBCLASS:
		{
		  struct lf_vbclass *vbc = (struct lf_vbclass *) ptr;
		  size_t subtype_len;
		  uint16_t offset;

		  if (left < sizeof (struct lf_vbclass))
		    {
		      einfo (_("%P: warning: truncated CodeView type record"
			       " LF_VBCLASS/LF_IVBCLASS\n"));
		      return false;
		    }

		  if (!remap_type (&vbc->base_class_type, map, type_num,
				   num_types))
		    return false;

		  if (!remap_type (&vbc->virtual_base_pointer_type, map,
				   type_num, num_types))
		    return false;

		  subtype_len = offsetof (struct lf_vbclass,
					  virtual_base_vbtable_offset);

		  offset = bfd_getl16 (&vbc->virtual_base_pointer_offset);

		  /* If offset >= 0x8000, actual value follows.  */
		  if (offset >= 0x8000)
		    {
		      unsigned int param_len = extended_value_len (offset);

		      if (param_len == 0)
			{
			  einfo (_("%P: warning: unhandled type %v within"
				   " LF_VBCLASS/LF_IVBCLASS\n"), offset);
			  return false;
			}

		      subtype_len += param_len;

		      if (left < subtype_len)
			{
			  einfo (_("%P: warning: truncated CodeView type record"
				   " LF_VBCLASS/LF_IVBCLASS\n"));
			  return false;
			}
		    }

		  offset = bfd_getl16 ((char *)vbc + subtype_len);
		  subtype_len += sizeof (uint16_t);

		  /* If offset >= 0x8000, actual value follows.  */
		  if (offset >= 0x8000)
		    {
		      unsigned int param_len = extended_value_len (offset);

		      if (param_len == 0)
			{
			  einfo (_("%P: warning: unhandled type %v within"
				   " LF_VBCLASS/LF_IVBCLASS\n"), offset);
			  return false;
			}

		      subtype_len += param_len;

		      if (left < subtype_len)
			{
			  einfo (_("%P: warning: truncated CodeView type record"
				   " LF_VBCLASS/LF_IVBCLASS\n"));
			  return false;
			}
		    }

		  if (subtype_len % 4 != 0)
		    subtype_len += 4 - (subtype_len % 4);

		  if (left < subtype_len)
		    {
		      einfo (_("%P: warning: truncated CodeView type record"
			       " LF_VBCLASS/LF_IVBCLASS\n"));
		      return false;
		    }

		  ptr += subtype_len;
		  left -= subtype_len;

		  break;
		}

	      case LF_STMEMBER:
		{
		  struct lf_static_member *st =
		    (struct lf_static_member *) ptr;
		  size_t name_len, subtype_len;

		  if (left < offsetof (struct lf_static_member, name))
		    {
		      einfo (_("%P: warning: truncated CodeView type record"
			       " LF_STMEMBER\n"));
		      return false;
		    }

		  if (!remap_type (&st->type, map, type_num, num_types))
		    return false;

		  name_len =
		    strnlen (st->name,
			     left - offsetof (struct lf_static_member, name));

		  if (name_len == left
				  - offsetof (struct lf_static_member, name))
		    {
		      einfo (_("%P: warning: name for LF_STMEMBER has no"
			       " terminating zero\n"));
		      return false;
		    }

		  name_len++;

		  subtype_len = offsetof (struct lf_static_member, name)
				+ name_len;

		  if (subtype_len % 4 != 0)
		    subtype_len += 4 - (subtype_len % 4);

		  if (left < subtype_len)
		    {
		      einfo (_("%P: warning: truncated CodeView type record"
			       " LF_FIELDLIST\n"));
		      return false;
		    }

		  ptr += subtype_len;
		  left -= subtype_len;

		  break;
		}

	      case LF_NESTTYPE:
		{
		  struct lf_nest_type *nest = (struct lf_nest_type *) ptr;
		  size_t name_len, subtype_len;

		  if (left < offsetof (struct lf_nest_type, name))
		    {
		      einfo (_("%P: warning: truncated CodeView type record"
			       " LF_NESTTYPE\n"));
		      return false;
		    }

		  if (!remap_type (&nest->type, map, type_num, num_types))
		    return false;

		  name_len =
		    strnlen (nest->name,
			     left - offsetof (struct lf_nest_type, name));

		  if (name_len == left - offsetof (struct lf_nest_type, name))
		    {
		      einfo (_("%P: warning: name for LF_NESTTYPE has no"
			       " terminating zero\n"));
		      return false;
		    }

		  name_len++;

		  subtype_len = offsetof (struct lf_nest_type, name)
				+ name_len;

		  if (subtype_len % 4 != 0)
		    subtype_len += 4 - (subtype_len % 4);

		  if (left < subtype_len)
		    {
		      einfo (_("%P: warning: truncated CodeView type record"
			       " LF_FIELDLIST\n"));
		      return false;
		    }

		  ptr += subtype_len;
		  left -= subtype_len;

		  break;
		}

	      default:
		einfo (_("%P: warning: unrecognized CodeView subtype %v\n"),
		       subtype);
		return false;
	      }
	  }

	break;
      }

    case LF_BITFIELD:
      {
	struct lf_bitfield *bf = (struct lf_bitfield *) data;

	if (size < offsetof (struct lf_bitfield, length))
	  {
	    einfo (_("%P: warning: truncated CodeView type record"
		     " LF_BITFIELD\n"));
	    return false;
	  }

	if (!remap_type (&bf->base_type, map, type_num, num_types))
	  return false;

	break;
      }

    case LF_METHODLIST:
      {
	struct lf_methodlist *ml = (struct lf_methodlist *) data;
	unsigned int num_entries;

	if (size < offsetof (struct lf_methodlist, entries))
	  {
	    einfo (_("%P: warning: truncated CodeView type record"
		     " LF_METHODLIST\n"));
	    return false;
	  }

	if ((size - offsetof (struct lf_methodlist, entries))
	    % sizeof (struct lf_methodlist_entry))
	  {
	    einfo (_("%P: warning: malformed CodeView type record"
		     " LF_METHODLIST\n"));
	    return false;
	  }

	num_entries = (size - offsetof (struct lf_methodlist, entries))
		      / sizeof (struct lf_methodlist_entry);

	for (unsigned int i = 0; i < num_entries; i++)
	  {
	    if (!remap_type (&ml->entries[i].method_type, map,
			     type_num, num_types))
	      return false;
	  }

	break;
      }

    case LF_ARRAY:
      {
	struct lf_array *arr = (struct lf_array *) data;

	if (size < offsetof (struct lf_array, length_in_bytes))
	  {
	    einfo (_("%P: warning: truncated CodeView type record"
		     " LF_ARRAY\n"));
	    return false;
	  }

	if (!remap_type (&arr->element_type, map, type_num, num_types))
	  return false;

	if (!remap_type (&arr->index_type, map, type_num, num_types))
	  return false;

	break;
      }

    case LF_CLASS:
    case LF_STRUCTURE:
      {
	struct lf_class *cl = (struct lf_class *) data;
	uint16_t prop, num_bytes;
	size_t name_len, name_off;

	if (size < offsetof (struct lf_class, name))
	  {
	    einfo (_("%P: warning: truncated CodeView type record"
		     " LF_CLASS/LF_STRUCTURE\n"));
	    return false;
	  }

	if (!remap_type (&cl->field_list, map, type_num, num_types))
	  return false;

	if (!remap_type (&cl->derived_from, map, type_num, num_types))
	  return false;

	if (!remap_type (&cl->vshape, map, type_num, num_types))
	  return false;

	name_off = offsetof (struct lf_class, name);

	num_bytes = bfd_getl16 (&cl->length);

	/* If num_bytes >= 0x8000, actual value follows.  */
	if (num_bytes >= 0x8000)
	  {
	    unsigned int param_len = extended_value_len (num_bytes);

	    if (param_len == 0)
	      {
		einfo (_("%P: warning: unhandled type %v within"
			 " LF_CLASS/LF_STRUCTURE\n"), num_bytes);
		return false;
	      }

	    name_off += param_len;

	    if (size < name_off)
	      {
		einfo (_("%P: warning: truncated CodeView type record"
			 " LF_CLASS/LF_STRUCTURE\n"));
		return false;
	      }
	  }

	name_len = strnlen ((char *) cl + name_off, size - name_off);

	if (name_len == size - name_off)
	  {
	    einfo (_("%P: warning: name for LF_CLASS/LF_STRUCTURE has no"
		     " terminating zero\n"));
	    return false;
	  }

	prop = bfd_getl16 (&cl->properties);

	if (prop & CV_PROP_HAS_UNIQUE_NAME)
	  {
	    /* Structure has another name following first one.  */

	    size_t len = name_off + name_len + 1;
	    size_t unique_name_len;

	    unique_name_len = strnlen ((char *) cl + name_off + name_len + 1,
				       size - len);

	    if (unique_name_len == size - len)