gold/symtab.cc

   1 // symtab.cc -- the gold symbol table
   2
   3 // Copyright 2006, 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 <stdint.h>
  26 #include <string>
  27 #include <utility>
  28
  29 #include "object.h"
  30 #include "dynobj.h"
  31 #include "output.h"
  32 #include "target.h"
  33 #include "workqueue.h"
  34 #include "symtab.h"
  35
  36 namespace gold
  37 {
  38
  39 // Class Symbol.
  40
  41 // Initialize fields in Symbol.  This initializes everything except u_
  42 // and source_.
  43
  44 void
  45 Symbol::init_fields(const char* name, const char* version,
  46                     elfcpp::STT type, elfcpp::STB binding,
  47                     elfcpp::STV visibility, unsigned char nonvis)
  48 {
  49   this->name_ = name;
  50   this->version_ = version;
  51   this->symtab_index_ = 0;
  52   this->dynsym_index_ = 0;
  53   this->got_offset_ = 0;
  54   this->plt_offset_ = 0;
  55   this->type_ = type;
  56   this->binding_ = binding;
  57   this->visibility_ = visibility;
  58   this->nonvis_ = nonvis;
  59   this->is_target_special_ = false;
  60   this->is_def_ = false;
  61   this->is_forwarder_ = false;
  62   this->needs_dynsym_entry_ = false;
  63   this->in_reg_ = false;
  64   this->in_dyn_ = false;
  65   this->has_got_offset_ = false;
  66   this->has_plt_offset_ = false;
  67   this->has_warning_ = false;
  68 }
  69
  70 // Initialize the fields in the base class Symbol for SYM in OBJECT.
  71
  72 template<int size, bool big_endian>
  73 void
  74 Symbol::init_base(const char* name, const char* version, Object* object,
  75                   const elfcpp::Sym<size, big_endian>& sym)
  76 {
  77   this->init_fields(name, version, sym.get_st_type(), sym.get_st_bind(),
  78                     sym.get_st_visibility(), sym.get_st_nonvis());
  79   this->u_.from_object.object = object;
  80   // FIXME: Handle SHN_XINDEX.
  81   this->u_.from_object.shndx = sym.get_st_shndx();
  82   this->source_ = FROM_OBJECT;
  83   this->in_reg_ = !object->is_dynamic();
  84   this->in_dyn_ = object->is_dynamic();
  85 }
  86
  87 // Initialize the fields in the base class Symbol for a symbol defined
  88 // in an Output_data.
  89
  90 void
  91 Symbol::init_base(const char* name, Output_data* od, elfcpp::STT type,
  92                   elfcpp::STB binding, elfcpp::STV visibility,
  93                   unsigned char nonvis, bool offset_is_from_end)
  94 {
  95   this->init_fields(name, NULL, type, binding, visibility, nonvis);
  96   this->u_.in_output_data.output_data = od;
  97   this->u_.in_output_data.offset_is_from_end = offset_is_from_end;
  98   this->source_ = IN_OUTPUT_DATA;
  99   this->in_reg_ = true;
 100 }
 101
 102 // Initialize the fields in the base class Symbol for a symbol defined
 103 // in an Output_segment.
 104
 105 void
 106 Symbol::init_base(const char* name, Output_segment* os, elfcpp::STT type,
 107                   elfcpp::STB binding, elfcpp::STV visibility,
 108                   unsigned char nonvis, Segment_offset_base offset_base)
 109 {
 110   this->init_fields(name, NULL, type, binding, visibility, nonvis);
 111   this->u_.in_output_segment.output_segment = os;
 112   this->u_.in_output_segment.offset_base = offset_base;
 113   this->source_ = IN_OUTPUT_SEGMENT;
 114   this->in_reg_ = true;
 115 }
 116
 117 // Initialize the fields in the base class Symbol for a symbol defined
 118 // as a constant.
 119
 120 void
 121 Symbol::init_base(const char* name, elfcpp::STT type,
 122                   elfcpp::STB binding, elfcpp::STV visibility,
 123                   unsigned char nonvis)
 124 {
 125   this->init_fields(name, NULL, type, binding, visibility, nonvis);
 126   this->source_ = CONSTANT;
 127   this->in_reg_ = true;
 128 }
 129
 130 // Initialize the fields in Sized_symbol for SYM in OBJECT.
 131
 132 template<int size>
 133 template<bool big_endian>
 134 void
 135 Sized_symbol<size>::init(const char* name, const char* version, Object* object,
 136                          const elfcpp::Sym<size, big_endian>& sym)
 137 {
 138   this->init_base(name, version, object, sym);
 139   this->value_ = sym.get_st_value();
 140   this->symsize_ = sym.get_st_size();
 141 }
 142
 143 // Initialize the fields in Sized_symbol for a symbol defined in an
 144 // Output_data.
 145
 146 template<int size>
 147 void
 148 Sized_symbol<size>::init(const char* name, Output_data* od,
 149                          Value_type value, Size_type symsize,
 150                          elfcpp::STT type, elfcpp::STB binding,
 151                          elfcpp::STV visibility, unsigned char nonvis,
 152                          bool offset_is_from_end)
 153 {
 154   this->init_base(name, od, type, binding, visibility, nonvis,
 155                   offset_is_from_end);
 156   this->value_ = value;
 157   this->symsize_ = symsize;
 158 }
 159
 160 // Initialize the fields in Sized_symbol for a symbol defined in an
 161 // Output_segment.
 162
 163 template<int size>
 164 void
 165 Sized_symbol<size>::init(const char* name, Output_segment* os,
 166                          Value_type value, Size_type symsize,
 167                          elfcpp::STT type, elfcpp::STB binding,
 168                          elfcpp::STV visibility, unsigned char nonvis,
 169                          Segment_offset_base offset_base)
 170 {
 171   this->init_base(name, os, type, binding, visibility, nonvis, offset_base);
 172   this->value_ = value;
 173   this->symsize_ = symsize;
 174 }
 175
 176 // Initialize the fields in Sized_symbol for a symbol defined as a
 177 // constant.
 178
 179 template<int size>
 180 void
 181 Sized_symbol<size>::init(const char* name, Value_type value, Size_type symsize,
 182                          elfcpp::STT type, elfcpp::STB binding,
 183                          elfcpp::STV visibility, unsigned char nonvis)
 184 {
 185   this->init_base(name, type, binding, visibility, nonvis);
 186   this->value_ = value;
 187   this->symsize_ = symsize;
 188 }
 189
 190 // Class Symbol_table.
 191
 192 Symbol_table::Symbol_table()
 193   : size_(0), saw_undefined_(0), offset_(0), table_(), namepool_(),
 194     forwarders_(), commons_(), warnings_()
 195 {
 196 }
 197
 198 Symbol_table::~Symbol_table()
 199 {
 200 }
 201
 202 // The hash function.  The key is always canonicalized, so we use a
 203 // simple combination of the pointers.
 204
 205 size_t
 206 Symbol_table::Symbol_table_hash::operator()(const Symbol_table_key& key) const
 207 {
 208   return key.first ^ key.second;
 209 }
 210
 211 // The symbol table key equality function.  This is only called with
 212 // canonicalized name and version strings, so we can use pointer
 213 // comparison.
 214
 215 bool
 216 Symbol_table::Symbol_table_eq::operator()(const Symbol_table_key& k1,
 217                                           const Symbol_table_key& k2) const
 218 {
 219   return k1.first == k2.first && k1.second == k2.second;
 220 }
 221
 222 // Make TO a symbol which forwards to FROM.
 223
 224 void
 225 Symbol_table::make_forwarder(Symbol* from, Symbol* to)
 226 {
 227   gold_assert(from != to);
 228   gold_assert(!from->is_forwarder() && !to->is_forwarder());
 229   this->forwarders_[from] = to;
 230   from->set_forwarder();
 231 }
 232
 233 // Resolve the forwards from FROM, returning the real symbol.
 234
 235 Symbol*
 236 Symbol_table::resolve_forwards(const Symbol* from) const
 237 {
 238   gold_assert(from->is_forwarder());
 239   Unordered_map<const Symbol*, Symbol*>::const_iterator p =
 240     this->forwarders_.find(from);
 241   gold_assert(p != this->forwarders_.end());
 242   return p->second;
 243 }
 244
 245 // Look up a symbol by name.
 246
 247 Symbol*
 248 Symbol_table::lookup(const char* name, const char* version) const
 249 {
 250   Stringpool::Key name_key;
 251   name = this->namepool_.find(name, &name_key);
 252   if (name == NULL)
 253     return NULL;
 254
 255   Stringpool::Key version_key = 0;
 256   if (version != NULL)
 257     {
 258       version = this->namepool_.find(version, &version_key);
 259       if (version == NULL)
 260         return NULL;
 261     }
 262
 263   Symbol_table_key key(name_key, version_key);
 264   Symbol_table::Symbol_table_type::const_iterator p = this->table_.find(key);
 265   if (p == this->table_.end())
 266     return NULL;
 267   return p->second;
 268 }
 269
 270 // Resolve a Symbol with another Symbol.  This is only used in the
 271 // unusual case where there are references to both an unversioned
 272 // symbol and a symbol with a version, and we then discover that that
 273 // version is the default version.  Because this is unusual, we do
 274 // this the slow way, by converting back to an ELF symbol.
 275
 276 template<int size, bool big_endian>
 277 void
 278 Symbol_table::resolve(Sized_symbol<size>* to, const Sized_symbol<size>* from,
 279                       const char* version ACCEPT_SIZE_ENDIAN)
 280 {
 281   unsigned char buf[elfcpp::Elf_sizes<size>::sym_size];
 282   elfcpp::Sym_write<size, big_endian> esym(buf);
 283   // We don't bother to set the st_name field.
 284   esym.put_st_value(from->value());
 285   esym.put_st_size(from->symsize());
 286   esym.put_st_info(from->binding(), from->type());
 287   esym.put_st_other(from->visibility(), from->nonvis());
 288   esym.put_st_shndx(from->shndx());
 289   Symbol_table::resolve(to, esym.sym(), from->object(), version);
 290   if (from->in_reg())
 291     to->set_in_reg();
 292   if (from->in_dyn())
 293     to->set_in_dyn();
 294 }
 295
 296 // Add one symbol from OBJECT to the symbol table.  NAME is symbol
 297 // name and VERSION is the version; both are canonicalized.  DEF is
 298 // whether this is the default version.
 299
 300 // If DEF is true, then this is the definition of a default version of
 301 // a symbol.  That means that any lookup of NAME/NULL and any lookup
 302 // of NAME/VERSION should always return the same symbol.  This is
 303 // obvious for references, but in particular we want to do this for
 304 // definitions: overriding NAME/NULL should also override
 305 // NAME/VERSION.  If we don't do that, it would be very hard to
 306 // override functions in a shared library which uses versioning.
 307
 308 // We implement this by simply making both entries in the hash table
 309 // point to the same Symbol structure.  That is easy enough if this is
 310 // the first time we see NAME/NULL or NAME/VERSION, but it is possible
 311 // that we have seen both already, in which case they will both have
 312 // independent entries in the symbol table.  We can't simply change
 313 // the symbol table entry, because we have pointers to the entries
 314 // attached to the object files.  So we mark the entry attached to the
 315 // object file as a forwarder, and record it in the forwarders_ map.
 316 // Note that entries in the hash table will never be marked as
 317 // forwarders.
 318
 319 template<int size, bool big_endian>
 320 Symbol*
 321 Symbol_table::add_from_object(Object* object,
 322                               const char *name,
 323                               Stringpool::Key name_key,
 324                               const char *version,
 325                               Stringpool::Key version_key,
 326                               bool def,
 327                               const elfcpp::Sym<size, big_endian>& sym)
 328 {
 329   Symbol* const snull = NULL;
 330   std::pair<typename Symbol_table_type::iterator, bool> ins =
 331     this->table_.insert(std::make_pair(std::make_pair(name_key, version_key),
 332                                        snull));
 333
 334   std::pair<typename Symbol_table_type::iterator, bool> insdef =
 335     std::make_pair(this->table_.end(), false);
 336   if (def)
 337     {
 338       const Stringpool::Key vnull_key = 0;
 339       insdef = this->table_.insert(std::make_pair(std::make_pair(name_key,
 340                                                                  vnull_key),
 341                                                   snull));
 342     }
 343
 344   // ins.first: an iterator, which is a pointer to a pair.
 345   // ins.first->first: the key (a pair of name and version).
 346   // ins.first->second: the value (Symbol*).
 347   // ins.second: true if new entry was inserted, false if not.
 348
 349   Sized_symbol<size>* ret;
 350   bool was_undefined;
 351   bool was_common;
 352   if (!ins.second)
 353     {
 354       // We already have an entry for NAME/VERSION.
 355       ret = this->get_sized_symbol SELECT_SIZE_NAME(size) (ins.first->second
 356                                                            SELECT_SIZE(size));
 357       gold_assert(ret != NULL);
 358
 359       was_undefined = ret->is_undefined();
 360       was_common = ret->is_common();
 361
 362       Symbol_table::resolve(ret, sym, object, version);
 363
 364       if (def)
 365         {
 366           if (insdef.second)
 367             {
 368               // This is the first time we have seen NAME/NULL.  Make
 369               // NAME/NULL point to NAME/VERSION.
 370               insdef.first->second = ret;
 371             }
 372           else if (insdef.first->second != ret)
 373             {
 374               // This is the unfortunate case where we already have
 375               // entries for both NAME/VERSION and NAME/NULL.
 376               const Sized_symbol<size>* sym2;
 377               sym2 = this->get_sized_symbol SELECT_SIZE_NAME(size) (
 378                 insdef.first->second
 379                 SELECT_SIZE(size));
 380               Symbol_table::resolve SELECT_SIZE_ENDIAN_NAME(size, big_endian) (
 381                 ret, sym2, version SELECT_SIZE_ENDIAN(size, big_endian));
 382               this->make_forwarder(insdef.first->second, ret);
 383               insdef.first->second = ret;
 384             }
 385         }
 386     }
 387   else
 388     {
 389       // This is the first time we have seen NAME/VERSION.
 390       gold_assert(ins.first->second == NULL);
 391
 392       was_undefined = false;
 393       was_common = false;
 394
 395       if (def && !insdef.second)
 396         {
 397           // We already have an entry for NAME/NULL.  If we override
 398           // it, then change it to NAME/VERSION.
 399           ret = this->get_sized_symbol SELECT_SIZE_NAME(size) (
 400               insdef.first->second
 401               SELECT_SIZE(size));
 402           Symbol_table::resolve(ret, sym, object, version);
 403           ins.first->second = ret;
 404         }
 405       else
 406         {
 407           Sized_target<size, big_endian>* target =
 408             object->sized_target SELECT_SIZE_ENDIAN_NAME(size, big_endian) (
 409                 SELECT_SIZE_ENDIAN_ONLY(size, big_endian));
 410           if (!target->has_make_symbol())
 411             ret = new Sized_symbol<size>();
 412           else
 413             {
 414               ret = target->make_symbol();
 415               if (ret == NULL)
 416                 {
 417                   // This means that we don't want a symbol table
 418                   // entry after all.
 419                   if (!def)
 420                     this->table_.erase(ins.first);
 421                   else
 422                     {
 423                       this->table_.erase(insdef.first);
 424                       // Inserting insdef invalidated ins.
 425                       this->table_.erase(std::make_pair(name_key,
 426                                                         version_key));
 427                     }
 428                   return NULL;
 429                 }
 430             }
 431
 432           ret->init(name, version, object, sym);
 433
 434           ins.first->second = ret;
 435           if (def)
 436             {
 437               // This is the first time we have seen NAME/NULL.  Point
 438               // it at the new entry for NAME/VERSION.
 439               gold_assert(insdef.second);
 440               insdef.first->second = ret;
 441             }
 442         }
 443     }
 444
 445   // Record every time we see a new undefined symbol, to speed up
 446   // archive groups.
 447   if (!was_undefined && ret->is_undefined())
 448     ++this->saw_undefined_;
 449
 450   // Keep track of common symbols, to speed up common symbol
 451   // allocation.
 452   if (!was_common && ret->is_common())
 453     this->commons_.push_back(ret);
 454
 455   return ret;
 456 }
 457
 458 // Add all the symbols in a relocatable object to the hash table.
 459
 460 template<int size, bool big_endian>
 461 void
 462 Symbol_table::add_from_relobj(
 463     Sized_relobj<size, big_endian>* relobj,
 464     const unsigned char* syms,
 465     size_t count,
 466     const char* sym_names,
 467     size_t sym_name_size,
 468     Symbol** sympointers)
 469 {
 470   // We take the size from the first object we see.
 471   if (this->get_size() == 0)
 472     this->set_size(size);
 473
 474   if (size != this->get_size() || size != relobj->target()->get_size())
 475     {
 476       fprintf(stderr, _("%s: %s: mixing 32-bit and 64-bit ELF objects\n"),
 477               program_name, relobj->name().c_str());
 478       gold_exit(false);
 479     }
 480
 481   const int sym_size = elfcpp::Elf_sizes<size>::sym_size;
 482
 483   const unsigned char* p = syms;
 484   for (size_t i = 0; i < count; ++i, p += sym_size)
 485     {
 486       elfcpp::Sym<size, big_endian> sym(p);
 487       elfcpp::Sym<size, big_endian>* psym = &sym;
 488
 489       unsigned int st_name = psym->get_st_name();
 490       if (st_name >= sym_name_size)
 491         {
 492           fprintf(stderr,
 493                   _("%s: %s: bad global symbol name offset %u at %lu\n"),
 494                   program_name, relobj->name().c_str(), st_name,
 495                   static_cast<unsigned long>(i));
 496           gold_exit(false);
 497         }
 498
 499       const char* name = sym_names + st_name;
 500
 501       // A symbol defined in a section which we are not including must
 502       // be treated as an undefined symbol.
 503       unsigned char symbuf[sym_size];
 504       elfcpp::Sym<size, big_endian> sym2(symbuf);
 505       unsigned int st_shndx = psym->get_st_shndx();
 506       if (st_shndx != elfcpp::SHN_UNDEF
 507           && st_shndx < elfcpp::SHN_LORESERVE
 508           && !relobj->is_section_included(st_shndx))
 509         {
 510           memcpy(symbuf, p, sym_size);
 511           elfcpp::Sym_write<size, big_endian> sw(symbuf);
 512           sw.put_st_shndx(elfcpp::SHN_UNDEF);
 513           psym = &sym2;
 514         }
 515
 516       // In an object file, an '@' in the name separates the symbol
 517       // name from the version name.  If there are two '@' characters,
 518       // this is the default version.
 519       const char* ver = strchr(name, '@');
 520
 521       Symbol* res;
 522       if (ver == NULL)
 523         {
 524           Stringpool::Key name_key;
 525           name = this->namepool_.add(name, &name_key);
 526           res = this->add_from_object(relobj, name, name_key, NULL, 0,
 527                                       false, *psym);
 528         }
 529       else
 530         {
 531           Stringpool::Key name_key;
 532           name = this->namepool_.add(name, ver - name, &name_key);
 533
 534           bool def = false;
 535           ++ver;
 536           if (*ver == '@')
 537             {
 538               def = true;
 539               ++ver;
 540             }
 541
 542           Stringpool::Key ver_key;
 543           ver = this->namepool_.add(ver, &ver_key);
 544
 545           res = this->add_from_object(relobj, name, name_key, ver, ver_key,
 546                                       def, *psym);
 547         }
 548
 549       *sympointers++ = res;
 550     }
 551 }
 552
 553 // Add all the symbols in a dynamic object to the hash table.
 554
 555 template<int size, bool big_endian>
 556 void
 557 Symbol_table::add_from_dynobj(
 558     Sized_dynobj<size, big_endian>* dynobj,
 559     const unsigned char* syms,
 560     size_t count,
 561     const char* sym_names,
 562     size_t sym_name_size,
 563     const unsigned char* versym,
 564     size_t versym_size,
 565     const std::vector<const char*>* version_map)
 566 {
 567   // We take the size from the first object we see.
 568   if (this->get_size() == 0)
 569     this->set_size(size);
 570
 571   if (size != this->get_size() || size != dynobj->target()->get_size())
 572     {
 573       fprintf(stderr, _("%s: %s: mixing 32-bit and 64-bit ELF objects\n"),
 574               program_name, dynobj->name().c_str());
 575       gold_exit(false);
 576     }
 577
 578   if (versym != NULL && versym_size / 2 < count)
 579     {
 580       fprintf(stderr, _("%s: %s: too few symbol versions\n"),
 581               program_name, dynobj->name().c_str());
 582       gold_exit(false);
 583     }
 584
 585   const int sym_size = elfcpp::Elf_sizes<size>::sym_size;
 586
 587   const unsigned char* p = syms;
 588   const unsigned char* vs = versym;
 589   for (size_t i = 0; i < count; ++i, p += sym_size, vs += 2)
 590     {
 591       elfcpp::Sym<size, big_endian> sym(p);
 592
 593       // Ignore symbols with local binding.
 594       if (sym.get_st_bind() == elfcpp::STB_LOCAL)
 595         continue;
 596
 597       unsigned int st_name = sym.get_st_name();
 598       if (st_name >= sym_name_size)
 599         {
 600           fprintf(stderr, _("%s: %s: bad symbol name offset %u at %lu\n"),
 601                   program_name, dynobj->name().c_str(), st_name,
 602                   static_cast<unsigned long>(i));
 603           gold_exit(false);
 604         }
 605
 606       const char* name = sym_names + st_name;
 607
 608       if (versym == NULL)
 609         {
 610           Stringpool::Key name_key;
 611           name = this->namepool_.add(name, &name_key);
 612           this->add_from_object(dynobj, name, name_key, NULL, 0,
 613                                 false, sym);
 614           continue;
 615         }
 616
 617       // Read the version information.
 618
 619       unsigned int v = elfcpp::Swap<16, big_endian>::readval(vs);
 620
 621       bool hidden = (v & elfcpp::VERSYM_HIDDEN) != 0;
 622       v &= elfcpp::VERSYM_VERSION;
 623
 624       // The Sun documentation says that V can be VER_NDX_LOCAL, or
 625       // VER_NDX_GLOBAL, or a version index.  The meaning of
 626       // VER_NDX_LOCAL is defined as "Symbol has local scope."  The
 627       // old GNU linker will happily generate VER_NDX_LOCAL for an
 628       // undefined symbol.  I don't know what the Sun linker will
 629       // generate.
 630
 631       if (v == static_cast<unsigned int>(elfcpp::VER_NDX_LOCAL)
 632           && sym.get_st_shndx() != elfcpp::SHN_UNDEF)
 633         {
 634           // This symbol should not be visible outside the object.
 635           continue;
 636         }
 637
 638       // At this point we are definitely going to add this symbol.
 639       Stringpool::Key name_key;
 640       name = this->namepool_.add(name, &name_key);
 641
 642       if (v == static_cast<unsigned int>(elfcpp::VER_NDX_LOCAL)
 643           || v == static_cast<unsigned int>(elfcpp::VER_NDX_GLOBAL))
 644         {
 645           // This symbol does not have a version.
 646           this->add_from_object(dynobj, name, name_key, NULL, 0, false, sym);
 647           continue;
 648         }
 649
 650       if (v >= version_map->size())
 651         {
 652           fprintf(stderr,
 653                   _("%s: %s: versym for symbol %zu out of range: %u\n"),
 654                   program_name, dynobj->name().c_str(), i, v);
 655           gold_exit(false);
 656         }
 657
 658       const char* version = (*version_map)[v];
 659       if (version == NULL)
 660         {
 661           fprintf(stderr, _("%s: %s: versym for symbol %zu has no name: %u\n"),
 662                   program_name, dynobj->name().c_str(), i, v);
 663           gold_exit(false);
 664         }
 665
 666       Stringpool::Key version_key;
 667       version = this->namepool_.add(version, &version_key);
 668
 669       // If this is an absolute symbol, and the version name and
 670       // symbol name are the same, then this is the version definition
 671       // symbol.  These symbols exist to support using -u to pull in
 672       // particular versions.  We do not want to record a version for
 673       // them.
 674       if (sym.get_st_shndx() == elfcpp::SHN_ABS && name_key == version_key)
 675         {
 676           this->add_from_object(dynobj, name, name_key, NULL, 0, false, sym);
 677           continue;
 678         }
 679
 680       const bool def = !hidden && sym.get_st_shndx() != elfcpp::SHN_UNDEF;
 681
 682       this->add_from_object(dynobj, name, name_key, version, version_key,
 683                             def, sym);
 684     }
 685 }
 686
 687 // Create and return a specially defined symbol.  If ONLY_IF_REF is
 688 // true, then only create the symbol if there is a reference to it.
 689 // If this does not return NULL, it sets *POLDSYM to the existing
 690 // symbol if there is one.  This canonicalizes *PNAME and *PVERSION.
 691
 692 template<int size, bool big_endian>
 693 Sized_symbol<size>*
 694 Symbol_table::define_special_symbol(const Target* target, const char** pname,
 695                                     const char** pversion, bool only_if_ref,
 696                                     Sized_symbol<size>** poldsym
 697                                     ACCEPT_SIZE_ENDIAN)
 698 {
 699   gold_assert(this->size_ == size);
 700
 701   Symbol* oldsym;
 702   Sized_symbol<size>* sym;
 703   bool add_to_table = false;
 704   typename Symbol_table_type::iterator add_loc = this->table_.end();
 705
 706   if (only_if_ref)
 707     {
 708       oldsym = this->lookup(*pname, *pversion);
 709       if (oldsym == NULL || !oldsym->is_undefined())
 710         return NULL;
 711
 712       *pname = oldsym->name();
 713       *pversion = oldsym->version();
 714     }
 715   else
 716     {
 717       // Canonicalize NAME and VERSION.
 718       Stringpool::Key name_key;
 719       *pname = this->namepool_.add(*pname, &name_key);
 720
 721       Stringpool::Key version_key = 0;
 722       if (*pversion != NULL)
 723         *pversion = this->namepool_.add(*pversion, &version_key);
 724
 725       Symbol* const snull = NULL;
 726       std::pair<typename Symbol_table_type::iterator, bool> ins =
 727         this->table_.insert(std::make_pair(std::make_pair(name_key,
 728                                                           version_key),
 729                                            snull));
 730
 731       if (!ins.second)
 732         {
 733           // We already have a symbol table entry for NAME/VERSION.
 734           oldsym = ins.first->second;
 735           gold_assert(oldsym != NULL);
 736         }
 737       else
 738         {
 739           // We haven't seen this symbol before.
 740           gold_assert(ins.first->second == NULL);
 741           add_to_table = true;
 742           add_loc = ins.first;
 743           oldsym = NULL;
 744         }
 745     }
 746
 747   if (!target->has_make_symbol())
 748     sym = new Sized_symbol<size>();
 749   else
 750     {
 751       gold_assert(target->get_size() == size);
 752       gold_assert(target->is_big_endian() ? big_endian : !big_endian);
 753       typedef Sized_target<size, big_endian> My_target;
 754       const My_target* sized_target =
 755           static_cast<const My_target*>(target);
 756       sym = sized_target->make_symbol();
 757       if (sym == NULL)
 758         return NULL;
 759     }
 760
 761   if (add_to_table)
 762     add_loc->second = sym;
 763   else
 764     gold_assert(oldsym != NULL);
 765
 766   *poldsym = this->get_sized_symbol SELECT_SIZE_NAME(size) (oldsym
 767                                                             SELECT_SIZE(size));
 768
 769   return sym;
 770 }
 771
 772 // Define a symbol based on an Output_data.
 773
 774 Symbol*
 775 Symbol_table::define_in_output_data(const Target* target, const char* name,
 776                                     const char* version, Output_data* od,
 777                                     uint64_t value, uint64_t symsize,
 778                                     elfcpp::STT type, elfcpp::STB binding,
 779                                     elfcpp::STV visibility,
 780                                     unsigned char nonvis,
 781                                     bool offset_is_from_end,
 782                                     bool only_if_ref)
 783 {
 784   gold_assert(target->get_size() == this->size_);
 785   if (this->size_ == 32)
 786     {
 787 #if defined(HAVE_TARGET_32_LITTLE) || defined(HAVE_TARGET_32_BIG)
 788       return this->do_define_in_output_data<32>(target, name, version, od,
 789                                                 value, symsize, type, binding,
 790                                                 visibility, nonvis,
 791                                                 offset_is_from_end,
 792                                                 only_if_ref);
 793 #else
 794       gold_unreachable();
 795 #endif
 796     }
 797   else if (this->size_ == 64)
 798     {
 799 #if defined(HAVE_TARGET_64_LITTLE) || defined(HAVE_TARGET_64_BIG)
 800       return this->do_define_in_output_data<64>(target, name, version, od,
 801                                                 value, symsize, type, binding,
 802                                                 visibility, nonvis,
 803                                                 offset_is_from_end,
 804                                                 only_if_ref);
 805 #else
 806       gold_unreachable();
 807 #endif
 808     }
 809   else
 810     gold_unreachable();
 811 }
 812
 813 // Define a symbol in an Output_data, sized version.
 814
 815 template<int size>
 816 Sized_symbol<size>*
 817 Symbol_table::do_define_in_output_data(
 818     const Target* target,
 819     const char* name,
 820     const char* version,
 821     Output_data* od,
 822     typename elfcpp::Elf_types<size>::Elf_Addr value,
 823     typename elfcpp::Elf_types<size>::Elf_WXword symsize,
 824     elfcpp::STT type,
 825     elfcpp::STB binding,
 826     elfcpp::STV visibility,
 827     unsigned char nonvis,
 828     bool offset_is_from_end,
 829     bool only_if_ref)
 830 {
 831   Sized_symbol<size>* sym;
 832   Sized_symbol<size>* oldsym;
 833
 834   if (target->is_big_endian())
 835     {
 836 #if defined(HAVE_TARGET_32_BIG) || defined(HAVE_TARGET_64_BIG)
 837       sym = this->define_special_symbol SELECT_SIZE_ENDIAN_NAME(size, true) (
 838           target, &name, &version, only_if_ref, &oldsym
 839           SELECT_SIZE_ENDIAN(size, true));
 840 #else
 841       gold_unreachable();
 842 #endif
 843     }
 844   else
 845     {
 846 #if defined(HAVE_TARGET_32_LITTLE) || defined(HAVE_TARGET_64_LITTLE)
 847       sym = this->define_special_symbol SELECT_SIZE_ENDIAN_NAME(size, false) (
 848           target, &name, &version, only_if_ref, &oldsym
 849           SELECT_SIZE_ENDIAN(size, false));
 850 #else
 851       gold_unreachable();
 852 #endif
 853     }
 854
 855   if (sym == NULL)
 856     return NULL;
 857
 858   gold_assert(version == NULL || oldsym != NULL);
 859   sym->init(name, od, value, symsize, type, binding, visibility, nonvis,
 860             offset_is_from_end);
 861
 862   if (oldsym != NULL
 863       && Symbol_table::should_override_with_special(oldsym))
 864     oldsym->override_with_special(sym);
 865
 866   return sym;
 867 }
 868
 869 // Define a symbol based on an Output_segment.
 870
 871 Symbol*
 872 Symbol_table::define_in_output_segment(const Target* target, const char* name,
 873                                        const char* version, Output_segment* os,
 874                                        uint64_t value, uint64_t symsize,
 875                                        elfcpp::STT type, elfcpp::STB binding,
 876                                        elfcpp::STV visibility,
 877                                        unsigned char nonvis,
 878                                        Symbol::Segment_offset_base offset_base,
 879                                        bool only_if_ref)
 880 {
 881   gold_assert(target->get_size() == this->size_);
 882   if (this->size_ == 32)
 883     {
 884 #if defined(HAVE_TARGET_32_LITTLE) || defined(HAVE_TARGET_32_BIG)
 885       return this->do_define_in_output_segment<32>(target, name, version, os,
 886                                                    value, symsize, type,
 887                                                    binding, visibility, nonvis,
 888                                                    offset_base, only_if_ref);
 889 #else
 890       gold_unreachable();
 891 #endif
 892     }
 893   else if (this->size_ == 64)
 894     {
 895 #if defined(HAVE_TARGET_64_LITTLE) || defined(HAVE_TARGET_64_BIG)
 896       return this->do_define_in_output_segment<64>(target, name, version, os,
 897                                                    value, symsize, type,
 898                                                    binding, visibility, nonvis,
 899                                                    offset_base, only_if_ref);
 900 #else
 901       gold_unreachable();
 902 #endif
 903     }
 904   else
 905     gold_unreachable();
 906 }
 907
 908 // Define a symbol in an Output_segment, sized version.
 909
 910 template<int size>
 911 Sized_symbol<size>*
 912 Symbol_table::do_define_in_output_segment(
 913     const Target* target,
 914     const char* name,
 915     const char* version,
 916     Output_segment* os,
 917     typename elfcpp::Elf_types<size>::Elf_Addr value,
 918     typename elfcpp::Elf_types<size>::Elf_WXword symsize,
 919     elfcpp::STT type,
 920     elfcpp::STB binding,
 921     elfcpp::STV visibility,
 922     unsigned char nonvis,
 923     Symbol::Segment_offset_base offset_base,
 924     bool only_if_ref)
 925 {
 926   Sized_symbol<size>* sym;
 927   Sized_symbol<size>* oldsym;
 928
 929   if (target->is_big_endian())
 930     sym = this->define_special_symbol SELECT_SIZE_ENDIAN_NAME(size, true) (
 931         target, &name, &version, only_if_ref, &oldsym
 932         SELECT_SIZE_ENDIAN(size, true));
 933   else
 934     sym = this->define_special_symbol SELECT_SIZE_ENDIAN_NAME(size, false) (
 935         target, &name, &version, only_if_ref, &oldsym
 936         SELECT_SIZE_ENDIAN(size, false));
 937
 938   if (sym == NULL)
 939     return NULL;
 940
 941   gold_assert(version == NULL || oldsym != NULL);
 942   sym->init(name, os, value, symsize, type, binding, visibility, nonvis,
 943             offset_base);
 944
 945   if (oldsym != NULL
 946       && Symbol_table::should_override_with_special(oldsym))
 947     oldsym->override_with_special(sym);
 948
 949   return sym;
 950 }
 951
 952 // Define a special symbol with a constant value.  It is a multiple
 953 // definition error if this symbol is already defined.
 954
 955 Symbol*
 956 Symbol_table::define_as_constant(const Target* target, const char* name,
 957                                  const char* version, uint64_t value,
 958                                  uint64_t symsize, elfcpp::STT type,
 959                                  elfcpp::STB binding, elfcpp::STV visibility,
 960                                  unsigned char nonvis, bool only_if_ref)
 961 {
 962   gold_assert(target->get_size() == this->size_);
 963   if (this->size_ == 32)
 964     {
 965 #if defined(HAVE_TARGET_32_LITTLE) || defined(HAVE_TARGET_32_BIG)
 966       return this->do_define_as_constant<32>(target, name, version, value,
 967                                              symsize, type, binding,
 968                                              visibility, nonvis, only_if_ref);
 969 #else
 970       gold_unreachable();
 971 #endif
 972     }
 973   else if (this->size_ == 64)
 974     {
 975 #if defined(HAVE_TARGET_64_LITTLE) || defined(HAVE_TARGET_64_BIG)
 976       return this->do_define_as_constant<64>(target, name, version, value,
 977                                              symsize, type, binding,
 978                                              visibility, nonvis, only_if_ref);
 979 #else
 980       gold_unreachable();
 981 #endif
 982     }
 983   else
 984     gold_unreachable();
 985 }
 986
 987 // Define a symbol as a constant, sized version.
 988
 989 template<int size>
 990 Sized_symbol<size>*
 991 Symbol_table::do_define_as_constant(
 992     const Target* target,
 993     const char* name,
 994     const char* version,
 995     typename elfcpp::Elf_types<size>::Elf_Addr value,
 996     typename elfcpp::Elf_types<size>::Elf_WXword symsize,
 997     elfcpp::STT type,
 998     elfcpp::STB binding,
 999     elfcpp::STV visibility,
1000     unsigned char nonvis,
1001     bool only_if_ref)
1002 {
1003   Sized_symbol<size>* sym;
1004   Sized_symbol<size>* oldsym;
1005
1006   if (target->is_big_endian())
1007     sym = this->define_special_symbol SELECT_SIZE_ENDIAN_NAME(size, true) (
1008         target, &name, &version, only_if_ref, &oldsym
1009         SELECT_SIZE_ENDIAN(size, true));
1010   else
1011     sym = this->define_special_symbol SELECT_SIZE_ENDIAN_NAME(size, false) (
1012         target, &name, &version, only_if_ref, &oldsym
1013         SELECT_SIZE_ENDIAN(size, false));
1014
1015   if (sym == NULL)
1016     return NULL;
1017
1018   gold_assert(version == NULL || oldsym != NULL);
1019   sym->init(name, value, symsize, type, binding, visibility, nonvis);
1020
1021   if (oldsym != NULL
1022       && Symbol_table::should_override_with_special(oldsym))
1023     oldsym->override_with_special(sym);
1024
1025   return sym;
1026 }
1027
1028 // Define a set of symbols in output sections.
1029
1030 void
1031 Symbol_table::define_symbols(const Layout* layout, const Target* target,
1032                              int count, const Define_symbol_in_section* p)
1033 {
1034   for (int i = 0; i < count; ++i, ++p)
1035     {
1036       Output_section* os = layout->find_output_section(p->output_section);
1037       if (os != NULL)
1038         this->define_in_output_data(target, p->name, NULL, os, p->value,
1039                                     p->size, p->type, p->binding,
1040                                     p->visibility, p->nonvis,
1041                                     p->offset_is_from_end, p->only_if_ref);
1042       else
1043         this->define_as_constant(target, p->name, NULL, 0, p->size, p->type,
1044                                  p->binding, p->visibility, p->nonvis,
1045                                  p->only_if_ref);
1046     }
1047 }
1048
1049 // Define a set of symbols in output segments.
1050
1051 void
1052 Symbol_table::define_symbols(const Layout* layout, const Target* target,
1053                              int count, const Define_symbol_in_segment* p)
1054 {
1055   for (int i = 0; i < count; ++i, ++p)
1056     {
1057       Output_segment* os = layout->find_output_segment(p->segment_type,
1058                                                        p->segment_flags_set,
1059                                                        p->segment_flags_clear);
1060       if (os != NULL)
1061         this->define_in_output_segment(target, p->name, NULL, os, p->value,
1062                                        p->size, p->type, p->binding,
1063                                        p->visibility, p->nonvis,
1064                                        p->offset_base, p->only_if_ref);
1065       else
1066         this->define_as_constant(target, p->name, NULL, 0, p->size, p->type,
1067                                  p->binding, p->visibility, p->nonvis,
1068                                  p->only_if_ref);
1069     }
1070 }
1071
1072 // Set the dynamic symbol indexes.  INDEX is the index of the first
1073 // global dynamic symbol.  Pointers to the symbols are stored into the
1074 // vector SYMS.  The names are added to DYNPOOL.  This returns an
1075 // updated dynamic symbol index.
1076
1077 unsigned int
1078 Symbol_table::set_dynsym_indexes(const General_options* options,
1079                                  const Target* target,
1080                                  unsigned int index,
1081                                  std::vector<Symbol*>* syms,
1082                                  Stringpool* dynpool,
1083                                  Versions* versions)
1084 {
1085   for (Symbol_table_type::iterator p = this->table_.begin();
1086        p != this->table_.end();
1087        ++p)
1088     {
1089       Symbol* sym = p->second;
1090
1091       // Note that SYM may already have a dynamic symbol index, since
1092       // some symbols appear more than once in the symbol table, with
1093       // and without a version.
1094
1095       if (!sym->needs_dynsym_entry()
1096           && (!options->export_dynamic()
1097               || !sym->in_reg()
1098               || !sym->is_externally_visible()))
1099         sym->set_dynsym_index(-1U);
1100       else if (!sym->has_dynsym_index())
1101         {
1102           sym->set_dynsym_index(index);
1103           ++index;
1104           syms->push_back(sym);
1105           dynpool->add(sym->name(), NULL);
1106
1107           // Record any version information.
1108           if (sym->version() != NULL)
1109             versions->record_version(options, dynpool, sym);
1110         }
1111     }
1112
1113   // Finish up the versions.  In some cases this may add new dynamic
1114   // symbols.
1115   index = versions->finalize(target, this, index, syms);
1116
1117   return index;
1118 }
1119
1120 // Set the final values for all the symbols.  The index of the first
1121 // global symbol in the output file is INDEX.  Record the file offset
1122 // OFF.  Add their names to POOL.  Return the new file offset.
1123
1124 off_t
1125 Symbol_table::finalize(unsigned int index, off_t off, off_t dynoff,
1126                        size_t dyn_global_index, size_t dyncount,
1127                        Stringpool* pool)
1128 {
1129   off_t ret;
1130
1131   gold_assert(index != 0);
1132   this->first_global_index_ = index;
1133
1134   this->dynamic_offset_ = dynoff;
1135   this->first_dynamic_global_index_ = dyn_global_index;
1136   this->dynamic_count_ = dyncount;
1137
1138   if (this->size_ == 32)
1139     ret = this->sized_finalize<32>(index, off, pool);
1140   else if (this->size_ == 64)
1141     ret = this->sized_finalize<64>(index, off, pool);
1142   else
1143     gold_unreachable();
1144
1145   // Now that we have the final symbol table, we can reliably note
1146   // which symbols should get warnings.
1147   this->warnings_.note_warnings(this);
1148
1149   return ret;
1150 }
1151
1152 // Set the final value for all the symbols.  This is called after
1153 // Layout::finalize, so all the output sections have their final
1154 // address.
1155
1156 template<int size>
1157 off_t
1158 Symbol_table::sized_finalize(unsigned index, off_t off, Stringpool* pool)
1159 {
1160   off = align_address(off, size >> 3);
1161   this->offset_ = off;
1162
1163   size_t orig_index = index;
1164
1165   const int sym_size = elfcpp::Elf_sizes<size>::sym_size;
1166   for (Symbol_table_type::iterator p = this->table_.begin();
1167        p != this->table_.end();
1168        ++p)
1169     {
1170       Sized_symbol<size>* sym = static_cast<Sized_symbol<size>*>(p->second);
1171
1172       // FIXME: Here we need to decide which symbols should go into
1173       // the output file, based on --strip.
1174
1175       // The default version of a symbol may appear twice in the
1176       // symbol table.  We only need to finalize it once.
1177       if (sym->has_symtab_index())
1178         continue;
1179
1180       if (!sym->in_reg())
1181         {
1182           gold_assert(!sym->has_symtab_index());
1183           sym->set_symtab_index(-1U);
1184           gold_assert(sym->dynsym_index() == -1U);
1185           continue;
1186         }
1187
1188       typename Sized_symbol<size>::Value_type value;
1189
1190       switch (sym->source())
1191         {
1192         case Symbol::FROM_OBJECT:
1193           {
1194             unsigned int shndx = sym->shndx();
1195
1196             // FIXME: We need some target specific support here.
1197             if (shndx >= elfcpp::SHN_LORESERVE
1198                 && shndx != elfcpp::SHN_ABS)
1199               {
1200                 fprintf(stderr, _("%s: %s: unsupported symbol section 0x%x\n"),
1201                         program_name, sym->name(), shndx);
1202                 gold_exit(false);
1203               }
1204
1205             Object* symobj = sym->object();
1206             if (symobj->is_dynamic())
1207               {
1208                 value = 0;
1209                 shndx = elfcpp::SHN_UNDEF;
1210               }
1211             else if (shndx == elfcpp::SHN_UNDEF)
1212               value = 0;
1213             else if (shndx == elfcpp::SHN_ABS)
1214               value = sym->value();
1215             else
1216               {
1217                 Relobj* relobj = static_cast<Relobj*>(symobj);
1218                 off_t secoff;
1219                 Output_section* os = relobj->output_section(shndx, &secoff);
1220
1221                 if (os == NULL)
1222                   {
1223                     sym->set_symtab_index(-1U);
1224                     gold_assert(sym->dynsym_index() == -1U);
1225                     continue;
1226                   }
1227
1228                 value = sym->value() + os->address() + secoff;
1229               }
1230           }
1231           break;
1232
1233         case Symbol::IN_OUTPUT_DATA:
1234           {
1235             Output_data* od = sym->output_data();
1236             value = sym->value() + od->address();
1237             if (sym->offset_is_from_end())
1238               value += od->data_size();
1239           }
1240           break;
1241
1242         case Symbol::IN_OUTPUT_SEGMENT:
1243           {
1244             Output_segment* os = sym->output_segment();
1245             value = sym->value() + os->vaddr();
1246             switch (sym->offset_base())
1247               {
1248               case Symbol::SEGMENT_START:
1249                 break;
1250               case Symbol::SEGMENT_END:
1251                 value += os->memsz();
1252                 break;
1253               case Symbol::SEGMENT_BSS:
1254                 value += os->filesz();
1255                 break;
1256               default:
1257                 gold_unreachable();
1258               }
1259           }
1260           break;
1261
1262         case Symbol::CONSTANT:
1263           value = sym->value();
1264           break;
1265
1266         default:
1267           gold_unreachable();
1268         }
1269
1270       sym->set_value(value);
1271       sym->set_symtab_index(index);
1272       pool->add(sym->name(), NULL);
1273       ++index;
1274       off += sym_size;
1275     }
1276
1277   this->output_count_ = index - orig_index;
1278
1279   return off;
1280 }
1281
1282 // Write out the global symbols.
1283
1284 void
1285 Symbol_table::write_globals(const Target* target, const Stringpool* sympool,
1286                             const Stringpool* dynpool, Output_file* of) const
1287 {
1288   if (this->size_ == 32)
1289     {
1290       if (target->is_big_endian())
1291         this->sized_write_globals<32, true>(target, sympool, dynpool, of);
1292       else
1293         this->sized_write_globals<32, false>(target, sympool, dynpool, of);
1294     }
1295   else if (this->size_ == 64)
1296     {
1297       if (target->is_big_endian())
1298         this->sized_write_globals<64, true>(target, sympool, dynpool, of);
1299       else
1300         this->sized_write_globals<64, false>(target, sympool, dynpool, of);
1301     }
1302   else
1303     gold_unreachable();
1304 }
1305
1306 // Write out the global symbols.
1307
1308 template<int size, bool big_endian>
1309 void
1310 Symbol_table::sized_write_globals(const Target*,
1311                                   const Stringpool* sympool,
1312                                   const Stringpool* dynpool,
1313                                   Output_file* of) const
1314 {
1315   const int sym_size = elfcpp::Elf_sizes<size>::sym_size;
1316   unsigned int index = this->first_global_index_;
1317   const off_t oview_size = this->output_count_ * sym_size;
1318   unsigned char* const psyms = of->get_output_view(this->offset_, oview_size);
1319
1320   unsigned int dynamic_count = this->dynamic_count_;
1321   off_t dynamic_size = dynamic_count * sym_size;
1322   unsigned int first_dynamic_global_index = this->first_dynamic_global_index_;
1323   unsigned char* dynamic_view;
1324   if (this->dynamic_offset_ == 0)
1325     dynamic_view = NULL;
1326   else
1327     dynamic_view = of->get_output_view(this->dynamic_offset_, dynamic_size);
1328
1329   unsigned char* ps = psyms;
1330   for (Symbol_table_type::const_iterator p = this->table_.begin();
1331        p != this->table_.end();
1332        ++p)
1333     {
1334       Sized_symbol<size>* sym = static_cast<Sized_symbol<size>*>(p->second);
1335
1336       unsigned int sym_index = sym->symtab_index();
1337       unsigned int dynsym_index;
1338       if (dynamic_view == NULL)
1339         dynsym_index = -1U;
1340       else
1341         dynsym_index = sym->dynsym_index();
1342
1343       if (sym_index == -1U && dynsym_index == -1U)
1344         {
1345           // This symbol is not included in the output file.
1346           continue;
1347         }
1348
1349       if (sym_index == index)
1350         ++index;
1351       else if (sym_index != -1U)
1352         {
1353           // We have already seen this symbol, because it has a
1354           // default version.
1355           gold_assert(sym_index < index);
1356           if (dynsym_index == -1U)
1357             continue;
1358           sym_index = -1U;
1359         }
1360
1361       unsigned int shndx;
1362       switch (sym->source())
1363         {
1364         case Symbol::FROM_OBJECT:
1365           {
1366             unsigned int in_shndx = sym->shndx();
1367
1368             // FIXME: We need some target specific support here.
1369             if (in_shndx >= elfcpp::SHN_LORESERVE
1370                 && in_shndx != elfcpp::SHN_ABS)
1371               {
1372                 fprintf(stderr, _("%s: %s: unsupported symbol section 0x%x\n"),
1373                         program_name, sym->name(), in_shndx);
1374                 gold_exit(false);
1375               }
1376
1377             Object* symobj = sym->object();
1378             if (symobj->is_dynamic())
1379               {
1380                 // FIXME.
1381                 shndx = elfcpp::SHN_UNDEF;
1382               }
1383             else if (in_shndx == elfcpp::SHN_UNDEF
1384                      || in_shndx == elfcpp::SHN_ABS)
1385               shndx = in_shndx;
1386             else
1387               {
1388                 Relobj* relobj = static_cast<Relobj*>(symobj);
1389                 off_t secoff;
1390                 Output_section* os = relobj->output_section(in_shndx, &secoff);
1391                 gold_assert(os != NULL);
1392                 shndx = os->out_shndx();
1393               }
1394           }
1395           break;
1396
1397         case Symbol::IN_OUTPUT_DATA:
1398           shndx = sym->output_data()->out_shndx();
1399           break;
1400
1401         case Symbol::IN_OUTPUT_SEGMENT:
1402           shndx = elfcpp::SHN_ABS;
1403           break;
1404
1405         case Symbol::CONSTANT:
1406           shndx = elfcpp::SHN_ABS;
1407           break;
1408
1409         default:
1410           gold_unreachable();
1411         }
1412
1413       if (sym_index != -1U)
1414         {
1415           this->sized_write_symbol SELECT_SIZE_ENDIAN_NAME(size, big_endian) (
1416               sym, shndx, sympool, ps
1417               SELECT_SIZE_ENDIAN(size, big_endian));
1418           ps += sym_size;
1419         }
1420
1421       if (dynsym_index != -1U)
1422         {
1423           dynsym_index -= first_dynamic_global_index;
1424           gold_assert(dynsym_index < dynamic_count);
1425           unsigned char* pd = dynamic_view + (dynsym_index * sym_size);
1426           this->sized_write_symbol SELECT_SIZE_ENDIAN_NAME(size, big_endian) (
1427               sym, shndx, dynpool, pd
1428               SELECT_SIZE_ENDIAN(size, big_endian));
1429         }
1430     }
1431
1432   gold_assert(ps - psyms == oview_size);
1433
1434   of->write_output_view(this->offset_, oview_size, psyms);
1435   if (dynamic_view != NULL)
1436     of->write_output_view(this->dynamic_offset_, dynamic_size, dynamic_view);
1437 }
1438
1439 // Write out the symbol SYM, in section SHNDX, to P.  POOL is the
1440 // strtab holding the name.
1441
1442 template<int size, bool big_endian>
1443 void
1444 Symbol_table::sized_write_symbol(Sized_symbol<size>* sym,
1445                                  unsigned int shndx,
1446                                  const Stringpool* pool,
1447                                  unsigned char* p
1448                                  ACCEPT_SIZE_ENDIAN) const
1449 {
1450   elfcpp::Sym_write<size, big_endian> osym(p);
1451   osym.put_st_name(pool->get_offset(sym->name()));
1452   osym.put_st_value(sym->value());
1453   osym.put_st_size(sym->symsize());
1454   osym.put_st_info(elfcpp::elf_st_info(sym->binding(), sym->type()));
1455   osym.put_st_other(elfcpp::elf_st_other(sym->visibility(), sym->nonvis()));
1456   osym.put_st_shndx(shndx);
1457 }
1458
1459 // Write out a section symbol.  Return the update offset.
1460
1461 void
1462 Symbol_table::write_section_symbol(const Target* target,
1463                                    const Output_section *os,
1464                                    Output_file* of,
1465                                    off_t offset) const
1466 {
1467   if (this->size_ == 32)
1468     {
1469       if (target->is_big_endian())
1470         this->sized_write_section_symbol<32, true>(os, of, offset);
1471       else
1472         this->sized_write_section_symbol<32, false>(os, of, offset);
1473     }
1474   else if (this->size_ == 64)
1475     {
1476       if (target->is_big_endian())
1477         this->sized_write_section_symbol<64, true>(os, of, offset);
1478       else
1479         this->sized_write_section_symbol<64, false>(os, of, offset);
1480     }
1481   else
1482     gold_unreachable();
1483 }
1484
1485 // Write out a section symbol, specialized for size and endianness.
1486
1487 template<int size, bool big_endian>
1488 void
1489 Symbol_table::sized_write_section_symbol(const Output_section* os,
1490                                          Output_file* of,
1491                                          off_t offset) const
1492 {
1493   const int sym_size = elfcpp::Elf_sizes<size>::sym_size;
1494
1495   unsigned char* pov = of->get_output_view(offset, sym_size);
1496
1497   elfcpp::Sym_write<size, big_endian> osym(pov);
1498   osym.put_st_name(0);
1499   osym.put_st_value(os->address());
1500   osym.put_st_size(0);
1501   osym.put_st_info(elfcpp::elf_st_info(elfcpp::STB_LOCAL,
1502                                        elfcpp::STT_SECTION));
1503   osym.put_st_other(elfcpp::elf_st_other(elfcpp::STV_DEFAULT, 0));
1504   osym.put_st_shndx(os->out_shndx());
1505
1506   of->write_output_view(offset, sym_size, pov);
1507 }
1508
1509 // Warnings functions.
1510
1511 // Add a new warning.
1512
1513 void
1514 Warnings::add_warning(Symbol_table* symtab, const char* name, Object* obj,
1515                       unsigned int shndx)
1516 {
1517   name = symtab->canonicalize_name(name);
1518   this->warnings_[name].set(obj, shndx);
1519 }
1520
1521 // Look through the warnings and mark the symbols for which we should
1522 // warn.  This is called during Layout::finalize when we know the
1523 // sources for all the symbols.
1524
1525 void
1526 Warnings::note_warnings(Symbol_table* symtab)
1527 {
1528   for (Warning_table::iterator p = this->warnings_.begin();
1529        p != this->warnings_.end();
1530        ++p)
1531     {
1532       Symbol* sym = symtab->lookup(p->first, NULL);
1533       if (sym != NULL
1534           && sym->source() == Symbol::FROM_OBJECT
1535           && sym->object() == p->second.object)
1536         {
1537           sym->set_has_warning();
1538
1539           // Read the section contents to get the warning text.  It
1540           // would be nicer if we only did this if we have to actually
1541           // issue a warning.  Unfortunately, warnings are issued as
1542           // we relocate sections.  That means that we can not lock
1543           // the object then, as we might try to issue the same
1544           // warning multiple times simultaneously.
1545           {
1546             Task_locker_obj<Object> tl(*p->second.object);
1547             const unsigned char* c;
1548             off_t len;
1549             c = p->second.object->section_contents(p->second.shndx, &len);
1550             p->second.set_text(reinterpret_cast<const char*>(c), len);
1551           }
1552         }
1553     }
1554 }
1555
1556 // Issue a warning.  This is called when we see a relocation against a
1557 // symbol for which has a warning.
1558
1559 void
1560 Warnings::issue_warning(const Symbol* sym, const std::string& location) const
1561 {
1562   gold_assert(sym->has_warning());
1563   Warning_table::const_iterator p = this->warnings_.find(sym->name());
1564   gold_assert(p != this->warnings_.end());
1565   fprintf(stderr, _("%s: %s: warning: %s\n"), program_name, location.c_str(),
1566           p->second.text.c_str());
1567 }
1568
1569 // Instantiate the templates we need.  We could use the configure
1570 // script to restrict this to only the ones needed for implemented
1571 // targets.
1572
1573 #ifdef HAVE_TARGET_32_LITTLE
1574 template
1575 void
1576 Symbol_table::add_from_relobj<32, false>(
1577     Sized_relobj<32, false>* relobj,
1578     const unsigned char* syms,
1579     size_t count,
1580     const char* sym_names,
1581     size_t sym_name_size,
1582     Symbol** sympointers);
1583 #endif
1584
1585 #ifdef HAVE_TARGET_32_BIG
1586 template
1587 void
1588 Symbol_table::add_from_relobj<32, true>(
1589     Sized_relobj<32, true>* relobj,
1590     const unsigned char* syms,
1591     size_t count,
1592     const char* sym_names,
1593     size_t sym_name_size,
1594     Symbol** sympointers);
1595 #endif
1596
1597 #ifdef HAVE_TARGET_64_LITTLE
1598 template
1599 void
1600 Symbol_table::add_from_relobj<64, false>(
1601     Sized_relobj<64, false>* relobj,
1602     const unsigned char* syms,
1603     size_t count,
1604     const char* sym_names,
1605     size_t sym_name_size,
1606     Symbol** sympointers);
1607 #endif
1608
1609 #ifdef HAVE_TARGET_64_BIG
1610 template
1611 void
1612 Symbol_table::add_from_relobj<64, true>(
1613     Sized_relobj<64, true>* relobj,
1614     const unsigned char* syms,
1615     size_t count,
1616     const char* sym_names,
1617     size_t sym_name_size,
1618     Symbol** sympointers);
1619 #endif
1620
1621 #ifdef HAVE_TARGET_32_LITTLE
1622 template
1623 void
1624 Symbol_table::add_from_dynobj<32, false>(
1625     Sized_dynobj<32, false>* dynobj,
1626     const unsigned char* syms,
1627     size_t count,
1628     const char* sym_names,
1629     size_t sym_name_size,
1630     const unsigned char* versym,
1631     size_t versym_size,
1632     const std::vector<const char*>* version_map);
1633 #endif
1634
1635 #ifdef HAVE_TARGET_32_BIG
1636 template
1637 void
1638 Symbol_table::add_from_dynobj<32, true>(
1639     Sized_dynobj<32, true>* dynobj,
1640     const unsigned char* syms,
1641     size_t count,
1642     const char* sym_names,
1643     size_t sym_name_size,
1644     const unsigned char* versym,
1645     size_t versym_size,
1646     const std::vector<const char*>* version_map);
1647 #endif
1648
1649 #ifdef HAVE_TARGET_64_LITTLE
1650 template
1651 void
1652 Symbol_table::add_from_dynobj<64, false>(
1653     Sized_dynobj<64, false>* dynobj,
1654     const unsigned char* syms,
1655     size_t count,
1656     const char* sym_names,
1657     size_t sym_name_size,
1658     const unsigned char* versym,
1659     size_t versym_size,
1660     const std::vector<const char*>* version_map);
1661 #endif
1662
1663 #ifdef HAVE_TARGET_64_BIG
1664 template
1665 void
1666 Symbol_table::add_from_dynobj<64, true>(
1667     Sized_dynobj<64, true>* dynobj,
1668     const unsigned char* syms,
1669     size_t count,
1670     const char* sym_names,
1671     size_t sym_name_size,
1672     const unsigned char* versym,
1673     size_t versym_size,
1674     const std::vector<const char*>* version_map);
1675 #endif
1676
1677 } // End namespace gold.