gold/dwarf_reader.cc

   1 // dwarf_reader.cc -- parse dwarf2/3 debug information
   2
   3 // Copyright 2007 Free Software Foundation, Inc.
   4 // Written by Ian Lance Taylor <iant@google.com>.
   5
   6 // This file is part of gold.
   7
   8 // This program is free software; you can redistribute it and/or modify
   9 // it under the terms of the GNU General Public License as published by
  10 // the Free Software Foundation; either version 3 of the License, or
  11 // (at your option) any later version.
  12
  13 // This program is distributed in the hope that it will be useful,
  14 // but WITHOUT ANY WARRANTY; without even the implied warranty of
  15 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16 // GNU General Public License for more details.
  17
  18 // You should have received a copy of the GNU General Public License
  19 // along with this program; if not, write to the Free Software
  20 // Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston,
  21 // MA 02110-1301, USA.
  22
  23 #include "gold.h"
  24
  25 #include "elfcpp_swap.h"
  26 #include "dwarf.h"
  27 #include "object.h"
  28 #include "parameters.h"
  29 #include "reloc.h"
  30 #include "dwarf_reader.h"
  31
  32 namespace {
  33
  34 // Read an unsigned LEB128 number.  Each byte contains 7 bits of
  35 // information, plus one bit saying whether the number continues or
  36 // not.
  37
  38 uint64_t
  39 read_unsigned_LEB_128(const unsigned char* buffer, size_t* len)
  40 {
  41   uint64_t result = 0;
  42   size_t num_read = 0;
  43   unsigned int shift = 0;
  44   unsigned char byte;
  45
  46   do
  47     {
  48       byte = *buffer++;
  49       num_read++;
  50       result |= (static_cast<uint64_t>(byte & 0x7f)) << shift;
  51       shift += 7;
  52     }
  53   while (byte & 0x80);
  54
  55   *len = num_read;
  56
  57   return result;
  58 }
  59
  60 // Read a signed LEB128 number.  These are like regular LEB128
  61 // numbers, except the last byte may have a sign bit set.
  62
  63 int64_t
  64 read_signed_LEB_128(const unsigned char* buffer, size_t* len)
  65 {
  66   int64_t result = 0;
  67   int shift = 0;
  68   size_t num_read = 0;
  69   unsigned char byte;
  70
  71   do
  72     {
  73       byte = *buffer++;
  74       num_read++;
  75       result |= (static_cast<uint64_t>(byte & 0x7f) << shift);
  76       shift += 7;
  77     }
  78   while (byte & 0x80);
  79
  80   if ((shift < 8 * static_cast<int>(sizeof(result))) && (byte & 0x40))
  81     result |= -((static_cast<int64_t>(1)) << shift);
  82   *len = num_read;
  83   return result;
  84 }
  85
  86 } // End anonymous namespace.
  87
  88
  89 namespace gold {
  90
  91 // This is the format of a DWARF2/3 line state machine that we process
  92 // opcodes using.  There is no need for anything outside the lineinfo
  93 // processor to know how this works.
  94
  95 struct LineStateMachine
  96 {
  97   int file_num;
  98   uint64_t address;
  99   int line_num;
 100   int column_num;
 101   unsigned int shndx;    // the section address refers to
 102   bool is_stmt;          // stmt means statement.
 103   bool basic_block;
 104   bool end_sequence;
 105 };
 106
 107 static void
 108 ResetLineStateMachine(struct LineStateMachine* lsm, bool default_is_stmt)
 109 {
 110   lsm->file_num = 1;
 111   lsm->address = 0;
 112   lsm->line_num = 1;
 113   lsm->column_num = 0;
 114   lsm->shndx = -1U;
 115   lsm->is_stmt = default_is_stmt;
 116   lsm->basic_block = false;
 117   lsm->end_sequence = false;
 118 }
 119
 120 template<int size, bool big_endian>
 121 Sized_dwarf_line_info<size, big_endian>::Sized_dwarf_line_info(Object* object)
 122   : data_valid_(false), buffer_(NULL), symtab_buffer_(NULL),
 123     directories_(), files_(), current_header_index_(-1)
 124 {
 125   unsigned int debug_shndx;
 126   for (debug_shndx = 0; debug_shndx < object->shnum(); ++debug_shndx)
 127     if (object->section_name(debug_shndx) == ".debug_line")
 128       {
 129         off_t buffer_size;
 130         this->buffer_ = object->section_contents(
 131             debug_shndx, &buffer_size, false);
 132         this->buffer_end_ = this->buffer_ + buffer_size;
 133         break;
 134       }
 135   if (this->buffer_ == NULL)
 136     return;
 137
 138   // Find the relocation section for ".debug_line".
 139   // We expect these for relobjs (.o's) but not dynobjs (.so's).
 140   bool got_relocs = false;
 141   for (unsigned int reloc_shndx = 0;
 142        reloc_shndx < object->shnum();
 143        ++reloc_shndx)
 144     {
 145       unsigned int reloc_sh_type = object->section_type(reloc_shndx);
 146       if ((reloc_sh_type == elfcpp::SHT_REL
 147            || reloc_sh_type == elfcpp::SHT_RELA)
 148           && object->section_info(reloc_shndx) == debug_shndx)
 149         {
 150           got_relocs = this->track_relocs_.initialize(object, reloc_shndx,
 151                                                       reloc_sh_type);
 152           break;
 153         }
 154     }
 155
 156   // Finally, we need the symtab section to interpret the relocs.
 157   if (got_relocs)
 158     {
 159       unsigned int symtab_shndx;
 160       for (symtab_shndx = 0; symtab_shndx < object->shnum(); ++symtab_shndx)
 161         if (object->section_type(symtab_shndx) == elfcpp::SHT_SYMTAB)
 162           {
 163             this->symtab_buffer_ = object->section_contents(
 164                 symtab_shndx, &this->symtab_buffer_size_, false);
 165             break;
 166           }
 167       if (this->symtab_buffer_ == NULL)
 168         return;
 169     }
 170
 171   // Now that we have successfully read all the data, parse the debug
 172   // info.
 173   this->data_valid_ = true;
 174   this->read_line_mappings();
 175 }
 176
 177 // Read the DWARF header.
 178
 179 template<int size, bool big_endian>
 180 const unsigned char*
 181 Sized_dwarf_line_info<size, big_endian>::read_header_prolog(
 182     const unsigned char* lineptr)
 183 {
 184   uint32_t initial_length = elfcpp::Swap<32, big_endian>::readval(lineptr);
 185   lineptr += 4;
 186
 187   // In DWARF2/3, if the initial length is all 1 bits, then the offset
 188   // size is 8 and we need to read the next 8 bytes for the real length.
 189   if (initial_length == 0xffffffff)
 190     {
 191       header_.offset_size = 8;
 192       initial_length = elfcpp::Swap<64, big_endian>::readval(lineptr);
 193       lineptr += 8;
 194     }
 195   else
 196     header_.offset_size = 4;
 197
 198   header_.total_length = initial_length;
 199
 200   gold_assert(lineptr + header_.total_length <= buffer_end_);
 201
 202   header_.version = elfcpp::Swap<16, big_endian>::readval(lineptr);
 203   lineptr += 2;
 204
 205   if (header_.offset_size == 4)
 206     header_.prologue_length = elfcpp::Swap<32, big_endian>::readval(lineptr);
 207   else
 208     header_.prologue_length = elfcpp::Swap<64, big_endian>::readval(lineptr);
 209   lineptr += header_.offset_size;
 210
 211   header_.min_insn_length = *lineptr;
 212   lineptr += 1;
 213
 214   header_.default_is_stmt = *lineptr;
 215   lineptr += 1;
 216
 217   header_.line_base = *reinterpret_cast<const signed char*>(lineptr);
 218   lineptr += 1;
 219
 220   header_.line_range = *lineptr;
 221   lineptr += 1;
 222
 223   header_.opcode_base = *lineptr;
 224   lineptr += 1;
 225
 226   header_.std_opcode_lengths.reserve(header_.opcode_base + 1);
 227   header_.std_opcode_lengths[0] = 0;
 228   for (int i = 1; i < header_.opcode_base; i++)
 229     {
 230       header_.std_opcode_lengths[i] = *lineptr;
 231       lineptr += 1;
 232     }
 233
 234   return lineptr;
 235 }
 236
 237 // The header for a debug_line section is mildly complicated, because
 238 // the line info is very tightly encoded.
 239
 240 template<int size, bool big_endian>
 241 const unsigned char*
 242 Sized_dwarf_line_info<size, big_endian>::read_header_tables(
 243     const unsigned char* lineptr)
 244 {
 245   ++this->current_header_index_;
 246
 247   // Create a new directories_ entry and a new files_ entry for our new
 248   // header.  We initialize each with a single empty element, because
 249   // dwarf indexes directory and filenames starting at 1.
 250   gold_assert(static_cast<int>(this->directories_.size())
 251               == this->current_header_index_);
 252   gold_assert(static_cast<int>(this->files_.size())
 253               == this->current_header_index_);
 254   this->directories_.push_back(std::vector<std::string>(1));
 255   this->files_.push_back(std::vector<std::pair<int, std::string> >(1));
 256
 257   // It is legal for the directory entry table to be empty.
 258   if (*lineptr)
 259     {
 260       int dirindex = 1;
 261       while (*lineptr)
 262         {
 263           const char* dirname = reinterpret_cast<const char*>(lineptr);
 264           gold_assert(dirindex
 265                       == static_cast<int>(this->directories_.back().size()));
 266           this->directories_.back().push_back(dirname);
 267           lineptr += this->directories_.back().back().size() + 1;
 268           dirindex++;
 269         }
 270     }
 271   lineptr++;
 272
 273   // It is also legal for the file entry table to be empty.
 274   if (*lineptr)
 275     {
 276       int fileindex = 1;
 277       size_t len;
 278       while (*lineptr)
 279         {
 280           const char* filename = reinterpret_cast<const char*>(lineptr);
 281           lineptr += strlen(filename) + 1;
 282
 283           uint64_t dirindex = read_unsigned_LEB_128(lineptr, &len);
 284           lineptr += len;
 285
 286           if (dirindex >= this->directories_.back().size())
 287             dirindex = 0;
 288           int dirindexi = static_cast<int>(dirindex);
 289
 290           read_unsigned_LEB_128(lineptr, &len);   // mod_time
 291           lineptr += len;
 292
 293           read_unsigned_LEB_128(lineptr, &len);   // filelength
 294           lineptr += len;
 295
 296           gold_assert(fileindex
 297                       == static_cast<int>(this->files_.back().size()));
 298           this->files_.back().push_back(std::make_pair(dirindexi, filename));
 299           fileindex++;
 300         }
 301     }
 302   lineptr++;
 303
 304   return lineptr;
 305 }
 306
 307 // Process a single opcode in the .debug.line structure.
 308
 309 // Templating on size and big_endian would yield more efficient (and
 310 // simpler) code, but would bloat the binary.  Speed isn't important
 311 // here.
 312
 313 template<int size, bool big_endian>
 314 bool
 315 Sized_dwarf_line_info<size, big_endian>::process_one_opcode(
 316     const unsigned char* start, struct LineStateMachine* lsm, size_t* len)
 317 {
 318   size_t oplen = 0;
 319   size_t templen;
 320   unsigned char opcode = *start;
 321   oplen++;
 322   start++;
 323
 324   // If the opcode is great than the opcode_base, it is a special
 325   // opcode. Most line programs consist mainly of special opcodes.
 326   if (opcode >= header_.opcode_base)
 327     {
 328       opcode -= header_.opcode_base;
 329       const int advance_address = ((opcode / header_.line_range)
 330                                    * header_.min_insn_length);
 331       lsm->address += advance_address;
 332
 333       const int advance_line = ((opcode % header_.line_range)
 334                                 + header_.line_base);
 335       lsm->line_num += advance_line;
 336       lsm->basic_block = true;
 337       *len = oplen;
 338       return true;
 339     }
 340
 341   // Otherwise, we have the regular opcodes
 342   switch (opcode)
 343     {
 344     case elfcpp::DW_LNS_copy:
 345       lsm->basic_block = false;
 346       *len = oplen;
 347       return true;
 348
 349     case elfcpp::DW_LNS_advance_pc:
 350       {
 351         const uint64_t advance_address
 352             = read_unsigned_LEB_128(start, &templen);
 353         oplen += templen;
 354         lsm->address += header_.min_insn_length * advance_address;
 355       }
 356       break;
 357
 358     case elfcpp::DW_LNS_advance_line:
 359       {
 360         const uint64_t advance_line = read_signed_LEB_128(start, &templen);
 361         oplen += templen;
 362         lsm->line_num += advance_line;
 363       }
 364       break;
 365
 366     case elfcpp::DW_LNS_set_file:
 367       {
 368         const uint64_t fileno = read_unsigned_LEB_128(start, &templen);
 369         oplen += templen;
 370         lsm->file_num = fileno;
 371       }
 372       break;
 373
 374     case elfcpp::DW_LNS_set_column:
 375       {
 376         const uint64_t colno = read_unsigned_LEB_128(start, &templen);
 377         oplen += templen;
 378         lsm->column_num = colno;
 379       }
 380       break;
 381
 382     case elfcpp::DW_LNS_negate_stmt:
 383       lsm->is_stmt = !lsm->is_stmt;
 384       break;
 385
 386     case elfcpp::DW_LNS_set_basic_block:
 387       lsm->basic_block = true;
 388       break;
 389
 390     case elfcpp::DW_LNS_fixed_advance_pc:
 391       {
 392         int advance_address;
 393         advance_address = elfcpp::Swap<16, big_endian>::readval(start);
 394         oplen += 2;
 395         lsm->address += advance_address;
 396       }
 397       break;
 398
 399     case elfcpp::DW_LNS_const_add_pc:
 400       {
 401         const int advance_address = (header_.min_insn_length
 402                                      * ((255 - header_.opcode_base)
 403                                         / header_.line_range));
 404         lsm->address += advance_address;
 405       }
 406       break;
 407
 408     case elfcpp::DW_LNS_extended_op:
 409       {
 410         const uint64_t extended_op_len
 411             = read_unsigned_LEB_128(start, &templen);
 412         start += templen;
 413         oplen += templen + extended_op_len;
 414
 415         const unsigned char extended_op = *start;
 416         start++;
 417
 418         switch (extended_op)
 419           {
 420           case elfcpp::DW_LNE_end_sequence:
 421             lsm->end_sequence = true;
 422             *len = oplen;
 423             return true;
 424
 425           case elfcpp::DW_LNE_set_address:
 426             {
 427               lsm->address = elfcpp::Swap<size, big_endian>::readval(start);
 428               typename Reloc_map::const_iterator it
 429                   = reloc_map_.find(start - this->buffer_);
 430               if (it != reloc_map_.end())
 431                 {
 432                   // value + addend.
 433                   lsm->address += it->second.second;
 434                   lsm->shndx = it->second.first;
 435                 }
 436               else
 437                 {
 438                   // If we're a normal .o file, with relocs, every
 439                   // set_address should have an associated relocation.
 440                   if (this->input_is_relobj())
 441                     this->data_valid_ = false;
 442                 }
 443               break;
 444             }
 445           case elfcpp::DW_LNE_define_file:
 446             {
 447               const char* filename  = reinterpret_cast<const char*>(start);
 448               templen = strlen(filename) + 1;
 449               start += templen;
 450
 451               uint64_t dirindex = read_unsigned_LEB_128(start, &templen);
 452               oplen += templen;
 453
 454               if (dirindex >= this->directories_.back().size())
 455                 dirindex = 0;
 456               int dirindexi = static_cast<int>(dirindex);
 457
 458               read_unsigned_LEB_128(start, &templen);   // mod_time
 459               oplen += templen;
 460
 461               read_unsigned_LEB_128(start, &templen);   // filelength
 462               oplen += templen;
 463
 464               this->files_.back().push_back(std::make_pair(dirindexi,
 465                                                            filename));
 466             }
 467             break;
 468           }
 469       }
 470       break;
 471
 472     default:
 473       {
 474         // Ignore unknown opcode  silently
 475         for (int i = 0; i < header_.std_opcode_lengths[opcode]; i++)
 476           {
 477             size_t templen;
 478             read_unsigned_LEB_128(start, &templen);
 479             start += templen;
 480             oplen += templen;
 481           }
 482       }
 483       break;
 484   }
 485   *len = oplen;
 486   return false;
 487 }
 488
 489 // Read the debug information at LINEPTR and store it in the line
 490 // number map.
 491
 492 template<int size, bool big_endian>
 493 unsigned const char*
 494 Sized_dwarf_line_info<size, big_endian>::read_lines(unsigned const char* lineptr)
 495 {
 496   struct LineStateMachine lsm;
 497
 498   // LENGTHSTART is the place the length field is based on.  It is the
 499   // point in the header after the initial length field.
 500   const unsigned char* lengthstart = buffer_;
 501
 502   // In 64 bit dwarf, the initial length is 12 bytes, because of the
 503   // 0xffffffff at the start.
 504   if (header_.offset_size == 8)
 505     lengthstart += 12;
 506   else
 507     lengthstart += 4;
 508
 509   while (lineptr < lengthstart + header_.total_length)
 510     {
 511       ResetLineStateMachine(&lsm, header_.default_is_stmt);
 512       while (!lsm.end_sequence)
 513         {
 514           size_t oplength;
 515           bool add_line = this->process_one_opcode(lineptr, &lsm, &oplength);
 516           if (add_line)
 517             {
 518               Offset_to_lineno_entry entry
 519                   = { lsm.address, this->current_header_index_,
 520                       lsm.file_num, lsm.line_num };
 521               line_number_map_[lsm.shndx].push_back(entry);
 522             }
 523           lineptr += oplength;
 524         }
 525     }
 526
 527   return lengthstart + header_.total_length;
 528 }
 529
 530 // Looks in the symtab to see what section a symbol is in.
 531
 532 template<int size, bool big_endian>
 533 unsigned int
 534 Sized_dwarf_line_info<size, big_endian>::symbol_section(
 535     unsigned int sym,
 536     typename elfcpp::Elf_types<size>::Elf_Addr* value)
 537 {
 538   const int symsize = elfcpp::Elf_sizes<size>::sym_size;
 539   gold_assert(sym * symsize < this->symtab_buffer_size_);
 540   elfcpp::Sym<size, big_endian> elfsym(this->symtab_buffer_ + sym * symsize);
 541   *value = elfsym.get_st_value();
 542   return elfsym.get_st_shndx();
 543 }
 544
 545 // Read the relocations into a Reloc_map.
 546
 547 template<int size, bool big_endian>
 548 void
 549 Sized_dwarf_line_info<size, big_endian>::read_relocs()
 550 {
 551   if (this->symtab_buffer_ == NULL)
 552     return;
 553
 554   typename elfcpp::Elf_types<size>::Elf_Addr value;
 555   off_t reloc_offset;
 556   while ((reloc_offset = this->track_relocs_.next_offset()) != -1)
 557     {
 558       const unsigned int sym = this->track_relocs_.next_symndx();
 559       const unsigned int shndx = this->symbol_section(sym, &value);
 560       this->reloc_map_[reloc_offset] = std::make_pair(shndx, value);
 561       this->track_relocs_.advance(reloc_offset + 1);
 562     }
 563 }
 564
 565 // Read the line number info.
 566
 567 template<int size, bool big_endian>
 568 void
 569 Sized_dwarf_line_info<size, big_endian>::read_line_mappings()
 570 {
 571   gold_assert(this->data_valid_ == true);
 572
 573   read_relocs();
 574   while (this->buffer_ < this->buffer_end_)
 575     {
 576       const unsigned char* lineptr = this->buffer_;
 577       lineptr = this->read_header_prolog(lineptr);
 578       lineptr = this->read_header_tables(lineptr);
 579       lineptr = this->read_lines(lineptr);
 580       this->buffer_ = lineptr;
 581     }
 582
 583   // Sort the lines numbers, so addr2line can use binary search.
 584   for (typename Lineno_map::iterator it = line_number_map_.begin();
 585        it != line_number_map_.end();
 586        ++it)
 587     // Each vector needs to be sorted by offset.
 588     std::sort(it->second.begin(), it->second.end());
 589 }
 590
 591 // Some processing depends on whether the input is a .o file or not.
 592 // For instance, .o files have relocs, and have .debug_lines
 593 // information on a per section basis.  .so files, on the other hand,
 594 // lack relocs, and offsets are unique, so we can ignore the section
 595 // information.
 596
 597 template<int size, bool big_endian>
 598 bool
 599 Sized_dwarf_line_info<size, big_endian>::input_is_relobj()
 600 {
 601   // Only .o files have relocs and the symtab buffer that goes with them.
 602   return this->symtab_buffer_ != NULL;
 603 }
 604
 605
 606 // Return a string for a file name and line number.
 607
 608 template<int size, bool big_endian>
 609 std::string
 610 Sized_dwarf_line_info<size, big_endian>::do_addr2line(unsigned int shndx,
 611                                                       off_t offset)
 612 {
 613   if (this->data_valid_ == false)
 614     return "";
 615
 616   const Offset_to_lineno_entry lookup_key = { offset, 0, 0, 0 };
 617   const std::vector<Offset_to_lineno_entry>* offsets;
 618   // If we do not have reloc information, then our input is a .so or
 619   // some similar data structure where all the information is held in
 620   // the offset.  In that case, we ignore the input shndx.
 621   if (this->input_is_relobj())
 622     offsets = &this->line_number_map_[shndx];
 623   else
 624     offsets = &this->line_number_map_[-1U];
 625   if (offsets->empty())
 626     return "";
 627
 628   typename std::vector<Offset_to_lineno_entry>::const_iterator it
 629       = std::lower_bound(offsets->begin(), offsets->end(), lookup_key);
 630
 631   // If we found an exact match, great, otherwise find the last entry
 632   // before the passed-in offset.
 633   if (it == offsets->end() || it->offset > offset)
 634     {
 635       if (it == offsets->begin())
 636         return "";
 637       --it;
 638       gold_assert(it->offset < offset);
 639     }
 640
 641   // Convert the file_num + line_num into a string.
 642   std::string ret;
 643
 644   gold_assert(it->header_num < static_cast<int>(this->files_.size()));
 645   gold_assert(it->file_num
 646               < static_cast<int>(this->files_[it->header_num].size()));
 647   const std::pair<int, std::string>& filename_pair
 648       = this->files_[it->header_num][it->file_num];
 649   const std::string& filename = filename_pair.second;
 650
 651   gold_assert(it->header_num < static_cast<int>(this->directories_.size()));
 652   gold_assert(filename_pair.first
 653               < static_cast<int>(this->directories_[it->header_num].size()));
 654   const std::string& dirname
 655       = this->directories_[it->header_num][filename_pair.first];
 656
 657   if (!dirname.empty())
 658     {
 659       ret += dirname;
 660       ret += "/";
 661     }
 662   ret += filename;
 663   if (ret.empty())
 664     ret = "(unknown)";
 665
 666   char buffer[64];   // enough to hold a line number
 667   snprintf(buffer, sizeof(buffer), "%d", it->line_num);
 668   ret += ":";
 669   ret += buffer;
 670
 671   return ret;
 672 }
 673
 674 // Dwarf_line_info routines.
 675
 676 std::string
 677 Dwarf_line_info::one_addr2line(Object* object,
 678                                unsigned int shndx, off_t offset)
 679 {
 680   if (parameters->get_size() == 32 && !parameters->is_big_endian())
 681 #ifdef HAVE_TARGET_32_LITTLE
 682     return Sized_dwarf_line_info<32, false>(object).addr2line(shndx, offset);
 683 #else
 684     gold_unreachable();
 685 #endif
 686   else if (parameters->get_size() == 32 && parameters->is_big_endian())
 687 #ifdef HAVE_TARGET_32_BIG
 688     return Sized_dwarf_line_info<32, true>(object).addr2line(shndx, offset);
 689 #else
 690     gold_unreachable();
 691 #endif
 692   else if (parameters->get_size() == 64 && !parameters->is_big_endian())
 693 #ifdef HAVE_TARGET_64_LITTLE
 694     return Sized_dwarf_line_info<64, false>(object).addr2line(shndx, offset);
 695 #else
 696     gold_unreachable();
 697 #endif
 698   else if (parameters->get_size() == 64 && parameters->is_big_endian())
 699 #ifdef HAVE_TARGET_64_BIT
 700     return Sized_dwarf_line_info<64, true>(object).addr2line(shndx, offset);
 701 #else
 702     gold_unreachable();
 703 #endif
 704   else
 705     gold_unreachable();
 706 }
 707
 708 #ifdef HAVE_TARGET_32_LITTLE
 709 template
 710 class Sized_dwarf_line_info<32, false>;
 711 #endif
 712
 713 #ifdef HAVE_TARGET_32_BIG
 714 template
 715 class Sized_dwarf_line_info<32, true>;
 716 #endif
 717
 718 #ifdef HAVE_TARGET_64_LITTLE
 719 template
 720 class Sized_dwarf_line_info<64, false>;
 721 #endif
 722
 723 #ifdef HAVE_TARGET_64_BIG
 724 template
 725 class Sized_dwarf_line_info<64, true>;
 726 #endif
 727
 728 } // End namespace gold.