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 // Return true if the final value of this symbol is known at link
 191 // time.
 192
 193 bool
 194 Symbol::final_value_is_known() const
 195 {
 196   // If we are not generating an executable, then no final values are
 197   // known, since they will change at runtime.
 198   if (!parameters->output_is_executable())
 199     return false;
 200
 201   // If the symbol is not from an object file, then it is defined, and
 202   // known.
 203   if (this->source_ != FROM_OBJECT)
 204     return true;
 205
 206   // If the symbol is from a dynamic object, then the final value is
 207   // not known.
 208   if (this->object()->is_dynamic())
 209     return false;
 210
 211   // If the symbol is not undefined (it is defined or common), then
 212   // the final value is known.
 213   if (!this->is_undefined())
 214     return true;
 215
 216   // If the symbol is undefined, then whether the final value is known
 217   // depends on whether we are doing a static link.  If we are doing a
 218   // dynamic link, then the final value could be filled in at runtime.
 219   // This could reasonably be the case for a weak undefined symbol.
 220   return parameters->doing_static_link();
 221 }
 222
 223 // Class Symbol_table.
 224
 225 Symbol_table::Symbol_table()
 226   : saw_undefined_(0), offset_(0), table_(), namepool_(),
 227     forwarders_(), commons_(), warnings_()
 228 {
 229 }
 230
 231 Symbol_table::~Symbol_table()
 232 {
 233 }
 234
 235 // The hash function.  The key is always canonicalized, so we use a
 236 // simple combination of the pointers.
 237
 238 size_t
 239 Symbol_table::Symbol_table_hash::operator()(const Symbol_table_key& key) const
 240 {
 241   return key.first ^ key.second;
 242 }
 243
 244 // The symbol table key equality function.  This is only called with
 245 // canonicalized name and version strings, so we can use pointer
 246 // comparison.
 247
 248 bool
 249 Symbol_table::Symbol_table_eq::operator()(const Symbol_table_key& k1,
 250                                           const Symbol_table_key& k2) const
 251 {
 252   return k1.first == k2.first && k1.second == k2.second;
 253 }
 254
 255 // Make TO a symbol which forwards to FROM.
 256
 257 void
 258 Symbol_table::make_forwarder(Symbol* from, Symbol* to)
 259 {
 260   gold_assert(from != to);
 261   gold_assert(!from->is_forwarder() && !to->is_forwarder());
 262   this->forwarders_[from] = to;
 263   from->set_forwarder();
 264 }
 265
 266 // Resolve the forwards from FROM, returning the real symbol.
 267
 268 Symbol*
 269 Symbol_table::resolve_forwards(const Symbol* from) const
 270 {
 271   gold_assert(from->is_forwarder());
 272   Unordered_map<const Symbol*, Symbol*>::const_iterator p =
 273     this->forwarders_.find(from);
 274   gold_assert(p != this->forwarders_.end());
 275   return p->second;
 276 }
 277
 278 // Look up a symbol by name.
 279
 280 Symbol*
 281 Symbol_table::lookup(const char* name, const char* version) const
 282 {
 283   Stringpool::Key name_key;
 284   name = this->namepool_.find(name, &name_key);
 285   if (name == NULL)
 286     return NULL;
 287
 288   Stringpool::Key version_key = 0;
 289   if (version != NULL)
 290     {
 291       version = this->namepool_.find(version, &version_key);
 292       if (version == NULL)
 293         return NULL;
 294     }
 295
 296   Symbol_table_key key(name_key, version_key);
 297   Symbol_table::Symbol_table_type::const_iterator p = this->table_.find(key);
 298   if (p == this->table_.end())
 299     return NULL;
 300   return p->second;
 301 }
 302
 303 // Resolve a Symbol with another Symbol.  This is only used in the
 304 // unusual case where there are references to both an unversioned
 305 // symbol and a symbol with a version, and we then discover that that
 306 // version is the default version.  Because this is unusual, we do
 307 // this the slow way, by converting back to an ELF symbol.
 308
 309 template<int size, bool big_endian>
 310 void
 311 Symbol_table::resolve(Sized_symbol<size>* to, const Sized_symbol<size>* from,
 312                       const char* version ACCEPT_SIZE_ENDIAN)
 313 {
 314   unsigned char buf[elfcpp::Elf_sizes<size>::sym_size];
 315   elfcpp::Sym_write<size, big_endian> esym(buf);
 316   // We don't bother to set the st_name field.
 317   esym.put_st_value(from->value());
 318   esym.put_st_size(from->symsize());
 319   esym.put_st_info(from->binding(), from->type());
 320   esym.put_st_other(from->visibility(), from->nonvis());
 321   esym.put_st_shndx(from->shndx());
 322   Symbol_table::resolve(to, esym.sym(), from->object(), version);
 323   if (from->in_reg())
 324     to->set_in_reg();
 325   if (from->in_dyn())
 326     to->set_in_dyn();
 327 }
 328
 329 // Add one symbol from OBJECT to the symbol table.  NAME is symbol
 330 // name and VERSION is the version; both are canonicalized.  DEF is
 331 // whether this is the default version.
 332
 333 // If DEF is true, then this is the definition of a default version of
 334 // a symbol.  That means that any lookup of NAME/NULL and any lookup
 335 // of NAME/VERSION should always return the same symbol.  This is
 336 // obvious for references, but in particular we want to do this for
 337 // definitions: overriding NAME/NULL should also override
 338 // NAME/VERSION.  If we don't do that, it would be very hard to
 339 // override functions in a shared library which uses versioning.
 340
 341 // We implement this by simply making both entries in the hash table
 342 // point to the same Symbol structure.  That is easy enough if this is
 343 // the first time we see NAME/NULL or NAME/VERSION, but it is possible
 344 // that we have seen both already, in which case they will both have
 345 // independent entries in the symbol table.  We can't simply change
 346 // the symbol table entry, because we have pointers to the entries
 347 // attached to the object files.  So we mark the entry attached to the
 348 // object file as a forwarder, and record it in the forwarders_ map.
 349 // Note that entries in the hash table will never be marked as
 350 // forwarders.
 351
 352 template<int size, bool big_endian>
 353 Symbol*
 354 Symbol_table::add_from_object(Object* object,
 355                               const char *name,
 356                               Stringpool::Key name_key,
 357                               const char *version,
 358                               Stringpool::Key version_key,
 359                               bool def,
 360                               const elfcpp::Sym<size, big_endian>& sym)
 361 {
 362   Symbol* const snull = NULL;
 363   std::pair<typename Symbol_table_type::iterator, bool> ins =
 364     this->table_.insert(std::make_pair(std::make_pair(name_key, version_key),
 365                                        snull));
 366
 367   std::pair<typename Symbol_table_type::iterator, bool> insdef =
 368     std::make_pair(this->table_.end(), false);
 369   if (def)
 370     {
 371       const Stringpool::Key vnull_key = 0;
 372       insdef = this->table_.insert(std::make_pair(std::make_pair(name_key,
 373                                                                  vnull_key),
 374                                                   snull));
 375     }
 376
 377   // ins.first: an iterator, which is a pointer to a pair.
 378   // ins.first->first: the key (a pair of name and version).
 379   // ins.first->second: the value (Symbol*).
 380   // ins.second: true if new entry was inserted, false if not.
 381
 382   Sized_symbol<size>* ret;
 383   bool was_undefined;
 384   bool was_common;
 385   if (!ins.second)
 386     {
 387       // We already have an entry for NAME/VERSION.
 388       ret = this->get_sized_symbol SELECT_SIZE_NAME(size) (ins.first->second
 389                                                            SELECT_SIZE(size));
 390       gold_assert(ret != NULL);
 391
 392       was_undefined = ret->is_undefined();
 393       was_common = ret->is_common();
 394
 395       Symbol_table::resolve(ret, sym, object, version);
 396
 397       if (def)
 398         {
 399           if (insdef.second)
 400             {
 401               // This is the first time we have seen NAME/NULL.  Make
 402               // NAME/NULL point to NAME/VERSION.
 403               insdef.first->second = ret;
 404             }
 405           else if (insdef.first->second != ret)
 406             {
 407               // This is the unfortunate case where we already have
 408               // entries for both NAME/VERSION and NAME/NULL.
 409               const Sized_symbol<size>* sym2;
 410               sym2 = this->get_sized_symbol SELECT_SIZE_NAME(size) (
 411                 insdef.first->second
 412                 SELECT_SIZE(size));
 413               Symbol_table::resolve SELECT_SIZE_ENDIAN_NAME(size, big_endian) (
 414                 ret, sym2, version SELECT_SIZE_ENDIAN(size, big_endian));
 415               this->make_forwarder(insdef.first->second, ret);
 416               insdef.first->second = ret;
 417             }
 418         }
 419     }
 420   else
 421     {
 422       // This is the first time we have seen NAME/VERSION.
 423       gold_assert(ins.first->second == NULL);
 424
 425       was_undefined = false;
 426       was_common = false;
 427
 428       if (def && !insdef.second)
 429         {
 430           // We already have an entry for NAME/NULL.  If we override
 431           // it, then change it to NAME/VERSION.
 432           ret = this->get_sized_symbol SELECT_SIZE_NAME(size) (
 433               insdef.first->second
 434               SELECT_SIZE(size));
 435           Symbol_table::resolve(ret, sym, object, version);
 436           ins.first->second = ret;
 437         }
 438       else
 439         {
 440           Sized_target<size, big_endian>* target =
 441             object->sized_target SELECT_SIZE_ENDIAN_NAME(size, big_endian) (
 442                 SELECT_SIZE_ENDIAN_ONLY(size, big_endian));
 443           if (!target->has_make_symbol())
 444             ret = new Sized_symbol<size>();
 445           else
 446             {
 447               ret = target->make_symbol();
 448               if (ret == NULL)
 449                 {
 450                   // This means that we don't want a symbol table
 451                   // entry after all.
 452                   if (!def)
 453                     this->table_.erase(ins.first);
 454                   else
 455                     {
 456                       this->table_.erase(insdef.first);
 457                       // Inserting insdef invalidated ins.
 458                       this->table_.erase(std::make_pair(name_key,
 459                                                         version_key));
 460                     }
 461                   return NULL;
 462                 }
 463             }
 464
 465           ret->init(name, version, object, sym);
 466
 467           ins.first->second = ret;
 468           if (def)
 469             {
 470               // This is the first time we have seen NAME/NULL.  Point
 471               // it at the new entry for NAME/VERSION.
 472               gold_assert(insdef.second);
 473               insdef.first->second = ret;
 474             }
 475         }
 476     }
 477
 478   // Record every time we see a new undefined symbol, to speed up
 479   // archive groups.
 480   if (!was_undefined && ret->is_undefined())
 481     ++this->saw_undefined_;
 482
 483   // Keep track of common symbols, to speed up common symbol
 484   // allocation.
 485   if (!was_common && ret->is_common())
 486     this->commons_.push_back(ret);
 487
 488   return ret;
 489 }
 490
 491 // Add all the symbols in a relocatable object to the hash table.
 492
 493 template<int size, bool big_endian>
 494 void
 495 Symbol_table::add_from_relobj(
 496     Sized_relobj<size, big_endian>* relobj,
 497     const unsigned char* syms,
 498     size_t count,
 499     const char* sym_names,
 500     size_t sym_name_size,
 501     Symbol** sympointers)
 502 {
 503   gold_assert(size == relobj->target()->get_size());
 504   gold_assert(size == parameters->get_size());
 505
 506   const int sym_size = elfcpp::Elf_sizes<size>::sym_size;
 507
 508   const unsigned char* p = syms;
 509   for (size_t i = 0; i < count; ++i, p += sym_size)
 510     {
 511       elfcpp::Sym<size, big_endian> sym(p);
 512       elfcpp::Sym<size, big_endian>* psym = &sym;
 513
 514       unsigned int st_name = psym->get_st_name();
 515       if (st_name >= sym_name_size)
 516         {
 517           relobj->error(_("bad global symbol name offset %u at %zu"),
 518                         st_name, i);
 519           continue;
 520         }
 521
 522       const char* name = sym_names + st_name;
 523
 524       // A symbol defined in a section which we are not including must
 525       // be treated as an undefined symbol.
 526       unsigned char symbuf[sym_size];
 527       elfcpp::Sym<size, big_endian> sym2(symbuf);
 528       unsigned int st_shndx = psym->get_st_shndx();
 529       if (st_shndx != elfcpp::SHN_UNDEF
 530           && st_shndx < elfcpp::SHN_LORESERVE
 531           && !relobj->is_section_included(st_shndx))
 532         {
 533           memcpy(symbuf, p, sym_size);
 534           elfcpp::Sym_write<size, big_endian> sw(symbuf);
 535           sw.put_st_shndx(elfcpp::SHN_UNDEF);
 536           psym = &sym2;
 537         }
 538
 539       // In an object file, an '@' in the name separates the symbol
 540       // name from the version name.  If there are two '@' characters,
 541       // this is the default version.
 542       const char* ver = strchr(name, '@');
 543
 544       Symbol* res;
 545       if (ver == NULL)
 546         {
 547           Stringpool::Key name_key;
 548           name = this->namepool_.add(name, true, &name_key);
 549           res = this->add_from_object(relobj, name, name_key, NULL, 0,
 550                                       false, *psym);
 551         }
 552       else
 553         {
 554           Stringpool::Key name_key;
 555           name = this->namepool_.add_prefix(name, ver - name, &name_key);
 556
 557           bool def = false;
 558           ++ver;
 559           if (*ver == '@')
 560             {
 561               def = true;
 562               ++ver;
 563             }
 564
 565           Stringpool::Key ver_key;
 566           ver = this->namepool_.add(ver, true, &ver_key);
 567
 568           res = this->add_from_object(relobj, name, name_key, ver, ver_key,
 569                                       def, *psym);
 570         }
 571
 572       *sympointers++ = res;
 573     }
 574 }
 575
 576 // Add all the symbols in a dynamic object to the hash table.
 577
 578 template<int size, bool big_endian>
 579 void
 580 Symbol_table::add_from_dynobj(
 581     Sized_dynobj<size, big_endian>* dynobj,
 582     const unsigned char* syms,
 583     size_t count,
 584     const char* sym_names,
 585     size_t sym_name_size,
 586     const unsigned char* versym,
 587     size_t versym_size,
 588     const std::vector<const char*>* version_map)
 589 {
 590   gold_assert(size == dynobj->target()->get_size());
 591   gold_assert(size == parameters->get_size());
 592
 593   if (versym != NULL && versym_size / 2 < count)
 594     {
 595       dynobj->error(_("too few symbol versions"));
 596       return;
 597     }
 598
 599   const int sym_size = elfcpp::Elf_sizes<size>::sym_size;
 600
 601   const unsigned char* p = syms;
 602   const unsigned char* vs = versym;
 603   for (size_t i = 0; i < count; ++i, p += sym_size, vs += 2)
 604     {
 605       elfcpp::Sym<size, big_endian> sym(p);
 606
 607       // Ignore symbols with local binding.
 608       if (sym.get_st_bind() == elfcpp::STB_LOCAL)
 609         continue;
 610
 611       unsigned int st_name = sym.get_st_name();
 612       if (st_name >= sym_name_size)
 613         {
 614           dynobj->error(_("bad symbol name offset %u at %zu"),
 615                         st_name, i);
 616           continue;
 617         }
 618
 619       const char* name = sym_names + st_name;
 620
 621       if (versym == NULL)
 622         {
 623           Stringpool::Key name_key;
 624           name = this->namepool_.add(name, true, &name_key);
 625           this->add_from_object(dynobj, name, name_key, NULL, 0,
 626                                 false, sym);
 627           continue;
 628         }
 629
 630       // Read the version information.
 631
 632       unsigned int v = elfcpp::Swap<16, big_endian>::readval(vs);
 633
 634       bool hidden = (v & elfcpp::VERSYM_HIDDEN) != 0;
 635       v &= elfcpp::VERSYM_VERSION;
 636
 637       // The Sun documentation says that V can be VER_NDX_LOCAL, or
 638       // VER_NDX_GLOBAL, or a version index.  The meaning of
 639       // VER_NDX_LOCAL is defined as "Symbol has local scope."  The
 640       // old GNU linker will happily generate VER_NDX_LOCAL for an
 641       // undefined symbol.  I don't know what the Sun linker will
 642       // generate.
 643
 644       if (v == static_cast<unsigned int>(elfcpp::VER_NDX_LOCAL)
 645           && sym.get_st_shndx() != elfcpp::SHN_UNDEF)
 646         {
 647           // This symbol should not be visible outside the object.
 648           continue;
 649         }
 650
 651       // At this point we are definitely going to add this symbol.
 652       Stringpool::Key name_key;
 653       name = this->namepool_.add(name, true, &name_key);
 654
 655       if (v == static_cast<unsigned int>(elfcpp::VER_NDX_LOCAL)
 656           || v == static_cast<unsigned int>(elfcpp::VER_NDX_GLOBAL))
 657         {
 658           // This symbol does not have a version.
 659           this->add_from_object(dynobj, name, name_key, NULL, 0, false, sym);
 660           continue;
 661         }
 662
 663       if (v >= version_map->size())
 664         {
 665           dynobj->error(_("versym for symbol %zu out of range: %u"), i, v);
 666           continue;
 667         }
 668
 669       const char* version = (*version_map)[v];
 670       if (version == NULL)
 671         {
 672           dynobj->error(_("versym for symbol %zu has no name: %u"), i, v);
 673           continue;
 674         }
 675
 676       Stringpool::Key version_key;
 677       version = this->namepool_.add(version, true, &version_key);
 678
 679       // If this is an absolute symbol, and the version name and
 680       // symbol name are the same, then this is the version definition
 681       // symbol.  These symbols exist to support using -u to pull in
 682       // particular versions.  We do not want to record a version for
 683       // them.
 684       if (sym.get_st_shndx() == elfcpp::SHN_ABS && name_key == version_key)
 685         {
 686           this->add_from_object(dynobj, name, name_key, NULL, 0, false, sym);
 687           continue;
 688         }
 689
 690       const bool def = !hidden && sym.get_st_shndx() != elfcpp::SHN_UNDEF;
 691
 692       this->add_from_object(dynobj, name, name_key, version, version_key,
 693                             def, sym);
 694     }
 695 }
 696
 697 // Create and return a specially defined symbol.  If ONLY_IF_REF is
 698 // true, then only create the symbol if there is a reference to it.
 699 // If this does not return NULL, it sets *POLDSYM to the existing
 700 // symbol if there is one.  This canonicalizes *PNAME and *PVERSION.
 701
 702 template<int size, bool big_endian>
 703 Sized_symbol<size>*
 704 Symbol_table::define_special_symbol(const Target* target, const char** pname,
 705                                     const char** pversion, bool only_if_ref,
 706                                     Sized_symbol<size>** poldsym
 707                                     ACCEPT_SIZE_ENDIAN)
 708 {
 709   Symbol* oldsym;
 710   Sized_symbol<size>* sym;
 711   bool add_to_table = false;
 712   typename Symbol_table_type::iterator add_loc = this->table_.end();
 713
 714   if (only_if_ref)
 715     {
 716       oldsym = this->lookup(*pname, *pversion);
 717       if (oldsym == NULL || !oldsym->is_undefined())
 718         return NULL;
 719
 720       *pname = oldsym->name();
 721       *pversion = oldsym->version();
 722     }
 723   else
 724     {
 725       // Canonicalize NAME and VERSION.
 726       Stringpool::Key name_key;
 727       *pname = this->namepool_.add(*pname, true, &name_key);
 728
 729       Stringpool::Key version_key = 0;
 730       if (*pversion != NULL)
 731         *pversion = this->namepool_.add(*pversion, true, &version_key);
 732
 733       Symbol* const snull = NULL;
 734       std::pair<typename Symbol_table_type::iterator, bool> ins =
 735         this->table_.insert(std::make_pair(std::make_pair(name_key,
 736                                                           version_key),
 737                                            snull));
 738
 739       if (!ins.second)
 740         {
 741           // We already have a symbol table entry for NAME/VERSION.
 742           oldsym = ins.first->second;
 743           gold_assert(oldsym != NULL);
 744         }
 745       else
 746         {
 747           // We haven't seen this symbol before.
 748           gold_assert(ins.first->second == NULL);
 749           add_to_table = true;
 750           add_loc = ins.first;
 751           oldsym = NULL;
 752         }
 753     }
 754
 755   if (!target->has_make_symbol())
 756     sym = new Sized_symbol<size>();
 757   else
 758     {
 759       gold_assert(target->get_size() == size);
 760       gold_assert(target->is_big_endian() ? big_endian : !big_endian);
 761       typedef Sized_target<size, big_endian> My_target;
 762       const My_target* sized_target =
 763           static_cast<const My_target*>(target);
 764       sym = sized_target->make_symbol();
 765       if (sym == NULL)
 766         return NULL;
 767     }
 768
 769   if (add_to_table)
 770     add_loc->second = sym;
 771   else
 772     gold_assert(oldsym != NULL);
 773
 774   *poldsym = this->get_sized_symbol SELECT_SIZE_NAME(size) (oldsym
 775                                                             SELECT_SIZE(size));
 776
 777   return sym;
 778 }
 779
 780 // Define a symbol based on an Output_data.
 781
 782 Symbol*
 783 Symbol_table::define_in_output_data(const Target* target, const char* name,
 784                                     const char* version, Output_data* od,
 785                                     uint64_t value, uint64_t symsize,
 786                                     elfcpp::STT type, elfcpp::STB binding,
 787                                     elfcpp::STV visibility,
 788                                     unsigned char nonvis,
 789                                     bool offset_is_from_end,
 790                                     bool only_if_ref)
 791 {
 792   if (parameters->get_size() == 32)
 793     {
 794 #if defined(HAVE_TARGET_32_LITTLE) || defined(HAVE_TARGET_32_BIG)
 795       return this->do_define_in_output_data<32>(target, name, version, od,
 796                                                 value, symsize, type, binding,
 797                                                 visibility, nonvis,
 798                                                 offset_is_from_end,
 799                                                 only_if_ref);
 800 #else
 801       gold_unreachable();
 802 #endif
 803     }
 804   else if (parameters->get_size() == 64)
 805     {
 806 #if defined(HAVE_TARGET_64_LITTLE) || defined(HAVE_TARGET_64_BIG)
 807       return this->do_define_in_output_data<64>(target, name, version, od,
 808                                                 value, symsize, type, binding,
 809                                                 visibility, nonvis,
 810                                                 offset_is_from_end,
 811                                                 only_if_ref);
 812 #else
 813       gold_unreachable();
 814 #endif
 815     }
 816   else
 817     gold_unreachable();
 818 }
 819
 820 // Define a symbol in an Output_data, sized version.
 821
 822 template<int size>
 823 Sized_symbol<size>*
 824 Symbol_table::do_define_in_output_data(
 825     const Target* target,
 826     const char* name,
 827     const char* version,
 828     Output_data* od,
 829     typename elfcpp::Elf_types<size>::Elf_Addr value,
 830     typename elfcpp::Elf_types<size>::Elf_WXword symsize,
 831     elfcpp::STT type,
 832     elfcpp::STB binding,
 833     elfcpp::STV visibility,
 834     unsigned char nonvis,
 835     bool offset_is_from_end,
 836     bool only_if_ref)
 837 {
 838   Sized_symbol<size>* sym;
 839   Sized_symbol<size>* oldsym;
 840
 841   if (parameters->is_big_endian())
 842     {
 843 #if defined(HAVE_TARGET_32_BIG) || defined(HAVE_TARGET_64_BIG)
 844       sym = this->define_special_symbol SELECT_SIZE_ENDIAN_NAME(size, true) (
 845           target, &name, &version, only_if_ref, &oldsym
 846           SELECT_SIZE_ENDIAN(size, true));
 847 #else
 848       gold_unreachable();
 849 #endif
 850     }
 851   else
 852     {
 853 #if defined(HAVE_TARGET_32_LITTLE) || defined(HAVE_TARGET_64_LITTLE)
 854       sym = this->define_special_symbol SELECT_SIZE_ENDIAN_NAME(size, false) (
 855           target, &name, &version, only_if_ref, &oldsym
 856           SELECT_SIZE_ENDIAN(size, false));
 857 #else
 858       gold_unreachable();
 859 #endif
 860     }
 861
 862   if (sym == NULL)
 863     return NULL;
 864
 865   gold_assert(version == NULL || oldsym != NULL);
 866   sym->init(name, od, value, symsize, type, binding, visibility, nonvis,
 867             offset_is_from_end);
 868
 869   if (oldsym != NULL
 870       && Symbol_table::should_override_with_special(oldsym))
 871     oldsym->override_with_special(sym);
 872
 873   return sym;
 874 }
 875
 876 // Define a symbol based on an Output_segment.
 877
 878 Symbol*
 879 Symbol_table::define_in_output_segment(const Target* target, const char* name,
 880                                        const char* version, Output_segment* os,
 881                                        uint64_t value, uint64_t symsize,
 882                                        elfcpp::STT type, elfcpp::STB binding,
 883                                        elfcpp::STV visibility,
 884                                        unsigned char nonvis,
 885                                        Symbol::Segment_offset_base offset_base,
 886                                        bool only_if_ref)
 887 {
 888   if (parameters->get_size() == 32)
 889     {
 890 #if defined(HAVE_TARGET_32_LITTLE) || defined(HAVE_TARGET_32_BIG)
 891       return this->do_define_in_output_segment<32>(target, name, version, os,
 892                                                    value, symsize, type,
 893                                                    binding, visibility, nonvis,
 894                                                    offset_base, only_if_ref);
 895 #else
 896       gold_unreachable();
 897 #endif
 898     }
 899   else if (parameters->get_size() == 64)
 900     {
 901 #if defined(HAVE_TARGET_64_LITTLE) || defined(HAVE_TARGET_64_BIG)
 902       return this->do_define_in_output_segment<64>(target, name, version, os,
 903                                                    value, symsize, type,
 904                                                    binding, visibility, nonvis,
 905                                                    offset_base, only_if_ref);
 906 #else
 907       gold_unreachable();
 908 #endif
 909     }
 910   else
 911     gold_unreachable();
 912 }
 913
 914 // Define a symbol in an Output_segment, sized version.
 915
 916 template<int size>
 917 Sized_symbol<size>*
 918 Symbol_table::do_define_in_output_segment(
 919     const Target* target,
 920     const char* name,
 921     const char* version,
 922     Output_segment* os,
 923     typename elfcpp::Elf_types<size>::Elf_Addr value,
 924     typename elfcpp::Elf_types<size>::Elf_WXword symsize,
 925     elfcpp::STT type,
 926     elfcpp::STB binding,
 927     elfcpp::STV visibility,
 928     unsigned char nonvis,
 929     Symbol::Segment_offset_base offset_base,
 930     bool only_if_ref)
 931 {
 932   Sized_symbol<size>* sym;
 933   Sized_symbol<size>* oldsym;
 934
 935   if (parameters->is_big_endian())
 936     {
 937 #if defined(HAVE_TARGET_32_BIG) || defined(HAVE_TARGET_64_BIG)
 938       sym = this->define_special_symbol SELECT_SIZE_ENDIAN_NAME(size, true) (
 939           target, &name, &version, only_if_ref, &oldsym
 940           SELECT_SIZE_ENDIAN(size, true));
 941 #else
 942       gold_unreachable();
 943 #endif
 944     }
 945   else
 946     {
 947 #if defined(HAVE_TARGET_32_LITTLE) || defined(HAVE_TARGET_64_LITTLE)
 948       sym = this->define_special_symbol SELECT_SIZE_ENDIAN_NAME(size, false) (
 949           target, &name, &version, only_if_ref, &oldsym
 950           SELECT_SIZE_ENDIAN(size, false));
 951 #else
 952       gold_unreachable();
 953 #endif
 954     }
 955
 956   if (sym == NULL)
 957     return NULL;
 958
 959   gold_assert(version == NULL || oldsym != NULL);
 960   sym->init(name, os, value, symsize, type, binding, visibility, nonvis,
 961             offset_base);
 962
 963   if (oldsym != NULL
 964       && Symbol_table::should_override_with_special(oldsym))
 965     oldsym->override_with_special(sym);
 966
 967   return sym;
 968 }
 969
 970 // Define a special symbol with a constant value.  It is a multiple
 971 // definition error if this symbol is already defined.
 972
 973 Symbol*
 974 Symbol_table::define_as_constant(const Target* target, const char* name,
 975                                  const char* version, uint64_t value,
 976                                  uint64_t symsize, elfcpp::STT type,
 977                                  elfcpp::STB binding, elfcpp::STV visibility,
 978                                  unsigned char nonvis, bool only_if_ref)
 979 {
 980   if (parameters->get_size() == 32)
 981     {
 982 #if defined(HAVE_TARGET_32_LITTLE) || defined(HAVE_TARGET_32_BIG)
 983       return this->do_define_as_constant<32>(target, name, version, value,
 984                                              symsize, type, binding,
 985                                              visibility, nonvis, only_if_ref);
 986 #else
 987       gold_unreachable();
 988 #endif
 989     }
 990   else if (parameters->get_size() == 64)
 991     {
 992 #if defined(HAVE_TARGET_64_LITTLE) || defined(HAVE_TARGET_64_BIG)
 993       return this->do_define_as_constant<64>(target, name, version, value,
 994                                              symsize, type, binding,
 995                                              visibility, nonvis, only_if_ref);
 996 #else
 997       gold_unreachable();
 998 #endif
 999     }
1000   else
1001     gold_unreachable();
1002 }
1003
1004 // Define a symbol as a constant, sized version.
1005
1006 template<int size>
1007 Sized_symbol<size>*
1008 Symbol_table::do_define_as_constant(
1009     const Target* target,
1010     const char* name,
1011     const char* version,
1012     typename elfcpp::Elf_types<size>::Elf_Addr value,
1013     typename elfcpp::Elf_types<size>::Elf_WXword symsize,
1014     elfcpp::STT type,
1015     elfcpp::STB binding,
1016     elfcpp::STV visibility,
1017     unsigned char nonvis,
1018     bool only_if_ref)
1019 {
1020   Sized_symbol<size>* sym;
1021   Sized_symbol<size>* oldsym;
1022
1023   if (parameters->is_big_endian())
1024     {
1025 #if defined(HAVE_TARGET_32_BIG) || defined(HAVE_TARGET_64_BIG)
1026       sym = this->define_special_symbol SELECT_SIZE_ENDIAN_NAME(size, true) (
1027           target, &name, &version, only_if_ref, &oldsym
1028           SELECT_SIZE_ENDIAN(size, true));
1029 #else
1030       gold_unreachable();
1031 #endif
1032     }
1033   else
1034     {
1035 #if defined(HAVE_TARGET_32_LITTLE) || defined(HAVE_TARGET_64_LITTLE)
1036       sym = this->define_special_symbol SELECT_SIZE_ENDIAN_NAME(size, false) (
1037           target, &name, &version, only_if_ref, &oldsym
1038           SELECT_SIZE_ENDIAN(size, false));
1039 #else
1040       gold_unreachable();
1041 #endif
1042     }
1043
1044   if (sym == NULL)
1045     return NULL;
1046
1047   gold_assert(version == NULL || oldsym != NULL);
1048   sym->init(name, value, symsize, type, binding, visibility, nonvis);
1049
1050   if (oldsym != NULL
1051       && Symbol_table::should_override_with_special(oldsym))
1052     oldsym->override_with_special(sym);
1053
1054   return sym;
1055 }
1056
1057 // Define a set of symbols in output sections.
1058
1059 void
1060 Symbol_table::define_symbols(const Layout* layout, const Target* target,
1061                              int count, const Define_symbol_in_section* p)
1062 {
1063   for (int i = 0; i < count; ++i, ++p)
1064     {
1065       Output_section* os = layout->find_output_section(p->output_section);
1066       if (os != NULL)
1067         this->define_in_output_data(target, p->name, NULL, os, p->value,
1068                                     p->size, p->type, p->binding,
1069                                     p->visibility, p->nonvis,
1070                                     p->offset_is_from_end, p->only_if_ref);
1071       else
1072         this->define_as_constant(target, p->name, NULL, 0, p->size, p->type,
1073                                  p->binding, p->visibility, p->nonvis,
1074                                  p->only_if_ref);
1075     }
1076 }
1077
1078 // Define a set of symbols in output segments.
1079
1080 void
1081 Symbol_table::define_symbols(const Layout* layout, const Target* target,
1082                              int count, const Define_symbol_in_segment* p)
1083 {
1084   for (int i = 0; i < count; ++i, ++p)
1085     {
1086       Output_segment* os = layout->find_output_segment(p->segment_type,
1087                                                        p->segment_flags_set,
1088                                                        p->segment_flags_clear);
1089       if (os != NULL)
1090         this->define_in_output_segment(target, p->name, NULL, os, p->value,
1091                                        p->size, p->type, p->binding,
1092                                        p->visibility, p->nonvis,
1093                                        p->offset_base, p->only_if_ref);
1094       else
1095         this->define_as_constant(target, p->name, NULL, 0, p->size, p->type,
1096                                  p->binding, p->visibility, p->nonvis,
1097                                  p->only_if_ref);
1098     }
1099 }
1100
1101 // Set the dynamic symbol indexes.  INDEX is the index of the first
1102 // global dynamic symbol.  Pointers to the symbols are stored into the
1103 // vector SYMS.  The names are added to DYNPOOL.  This returns an
1104 // updated dynamic symbol index.
1105
1106 unsigned int
1107 Symbol_table::set_dynsym_indexes(const General_options* options,
1108                                  const Target* target,
1109                                  unsigned int index,
1110                                  std::vector<Symbol*>* syms,
1111                                  Stringpool* dynpool,
1112                                  Versions* versions)
1113 {
1114   for (Symbol_table_type::iterator p = this->table_.begin();
1115        p != this->table_.end();
1116        ++p)
1117     {
1118       Symbol* sym = p->second;
1119
1120       // Note that SYM may already have a dynamic symbol index, since
1121       // some symbols appear more than once in the symbol table, with
1122       // and without a version.
1123
1124       if (!sym->needs_dynsym_entry()
1125           && (!options->export_dynamic()
1126               || !sym->in_reg()
1127               || !sym->is_externally_visible()))
1128         sym->set_dynsym_index(-1U);
1129       else if (!sym->has_dynsym_index())
1130         {
1131           sym->set_dynsym_index(index);
1132           ++index;
1133           syms->push_back(sym);
1134           dynpool->add(sym->name(), false, NULL);
1135
1136           // Record any version information.
1137           if (sym->version() != NULL)
1138             versions->record_version(options, dynpool, sym);
1139         }
1140     }
1141
1142   // Finish up the versions.  In some cases this may add new dynamic
1143   // symbols.
1144   index = versions->finalize(target, this, index, syms);
1145
1146   return index;
1147 }
1148
1149 // Set the final values for all the symbols.  The index of the first
1150 // global symbol in the output file is INDEX.  Record the file offset
1151 // OFF.  Add their names to POOL.  Return the new file offset.
1152
1153 off_t
1154 Symbol_table::finalize(unsigned int index, off_t off, off_t dynoff,
1155                        size_t dyn_global_index, size_t dyncount,
1156                        Stringpool* pool)
1157 {
1158   off_t ret;
1159
1160   gold_assert(index != 0);
1161   this->first_global_index_ = index;
1162
1163   this->dynamic_offset_ = dynoff;
1164   this->first_dynamic_global_index_ = dyn_global_index;
1165   this->dynamic_count_ = dyncount;
1166
1167   if (parameters->get_size() == 32)
1168     {
1169 #if defined(HAVE_TARGET_32_BIG) || defined(HAVE_TARGET_32_LITTLE)
1170       ret = this->sized_finalize<32>(index, off, pool);
1171 #else
1172       gold_unreachable();
1173 #endif
1174     }
1175   else if (parameters->get_size() == 64)
1176     {
1177 #if defined(HAVE_TARGET_64_BIG) || defined(HAVE_TARGET_64_LITTLE)
1178       ret = this->sized_finalize<64>(index, off, pool);
1179 #else
1180       gold_unreachable();
1181 #endif
1182     }
1183   else
1184     gold_unreachable();
1185
1186   // Now that we have the final symbol table, we can reliably note
1187   // which symbols should get warnings.
1188   this->warnings_.note_warnings(this);
1189
1190   return ret;
1191 }
1192
1193 // Set the final value for all the symbols.  This is called after
1194 // Layout::finalize, so all the output sections have their final
1195 // address.
1196
1197 template<int size>
1198 off_t
1199 Symbol_table::sized_finalize(unsigned index, off_t off, Stringpool* pool)
1200 {
1201   off = align_address(off, size >> 3);
1202   this->offset_ = off;
1203
1204   size_t orig_index = index;
1205
1206   const int sym_size = elfcpp::Elf_sizes<size>::sym_size;
1207   for (Symbol_table_type::iterator p = this->table_.begin();
1208        p != this->table_.end();
1209        ++p)
1210     {
1211       Sized_symbol<size>* sym = static_cast<Sized_symbol<size>*>(p->second);
1212
1213       // FIXME: Here we need to decide which symbols should go into
1214       // the output file, based on --strip.
1215
1216       // The default version of a symbol may appear twice in the
1217       // symbol table.  We only need to finalize it once.
1218       if (sym->has_symtab_index())
1219         continue;
1220
1221       if (!sym->in_reg())
1222         {
1223           gold_assert(!sym->has_symtab_index());
1224           sym->set_symtab_index(-1U);
1225           gold_assert(sym->dynsym_index() == -1U);
1226           continue;
1227         }
1228
1229       typename Sized_symbol<size>::Value_type value;
1230
1231       switch (sym->source())
1232         {
1233         case Symbol::FROM_OBJECT:
1234           {
1235             unsigned int shndx = sym->shndx();
1236
1237             // FIXME: We need some target specific support here.
1238             if (shndx >= elfcpp::SHN_LORESERVE
1239                 && shndx != elfcpp::SHN_ABS)
1240               {
1241                 gold_error(_("%s: unsupported symbol section 0x%x"),
1242                            sym->name(), shndx);
1243                 shndx = elfcpp::SHN_UNDEF;
1244               }
1245
1246             Object* symobj = sym->object();
1247             if (symobj->is_dynamic())
1248               {
1249                 value = 0;
1250                 shndx = elfcpp::SHN_UNDEF;
1251               }
1252             else if (shndx == elfcpp::SHN_UNDEF)
1253               value = 0;
1254             else if (shndx == elfcpp::SHN_ABS)
1255               value = sym->value();
1256             else
1257               {
1258                 Relobj* relobj = static_cast<Relobj*>(symobj);
1259                 off_t secoff;
1260                 Output_section* os = relobj->output_section(shndx, &secoff);
1261
1262                 if (os == NULL)
1263                   {
1264                     sym->set_symtab_index(-1U);
1265                     gold_assert(sym->dynsym_index() == -1U);
1266                     continue;
1267                   }
1268
1269                 value = sym->value() + os->address() + secoff;
1270               }
1271           }
1272           break;
1273
1274         case Symbol::IN_OUTPUT_DATA:
1275           {
1276             Output_data* od = sym->output_data();
1277             value = sym->value() + od->address();
1278             if (sym->offset_is_from_end())
1279               value += od->data_size();
1280           }
1281           break;
1282
1283         case Symbol::IN_OUTPUT_SEGMENT:
1284           {
1285             Output_segment* os = sym->output_segment();
1286             value = sym->value() + os->vaddr();
1287             switch (sym->offset_base())
1288               {
1289               case Symbol::SEGMENT_START:
1290                 break;
1291               case Symbol::SEGMENT_END:
1292                 value += os->memsz();
1293                 break;
1294               case Symbol::SEGMENT_BSS:
1295                 value += os->filesz();
1296                 break;
1297               default:
1298                 gold_unreachable();
1299               }
1300           }
1301           break;
1302
1303         case Symbol::CONSTANT:
1304           value = sym->value();
1305           break;
1306
1307         default:
1308           gold_unreachable();
1309         }
1310
1311       sym->set_value(value);
1312
1313       if (parameters->strip_all())
1314         sym->set_symtab_index(-1U);
1315       else
1316         {
1317           sym->set_symtab_index(index);
1318           pool->add(sym->name(), false, NULL);
1319           ++index;
1320           off += sym_size;
1321         }
1322     }
1323
1324   this->output_count_ = index - orig_index;
1325
1326   return off;
1327 }
1328
1329 // Write out the global symbols.
1330
1331 void
1332 Symbol_table::write_globals(const Target* target, const Stringpool* sympool,
1333                             const Stringpool* dynpool, Output_file* of) const
1334 {
1335   if (parameters->get_size() == 32)
1336     {
1337       if (parameters->is_big_endian())
1338         {
1339 #ifdef HAVE_TARGET_32_BIG
1340           this->sized_write_globals<32, true>(target, sympool, dynpool, of);
1341 #else
1342           gold_unreachable();
1343 #endif
1344         }
1345       else
1346         {
1347 #ifdef HAVE_TARGET_32_LITTLE
1348           this->sized_write_globals<32, false>(target, sympool, dynpool, of);
1349 #else
1350           gold_unreachable();
1351 #endif
1352         }
1353     }
1354   else if (parameters->get_size() == 64)
1355     {
1356       if (parameters->is_big_endian())
1357         {
1358 #ifdef HAVE_TARGET_64_BIG
1359           this->sized_write_globals<64, true>(target, sympool, dynpool, of);
1360 #else
1361           gold_unreachable();
1362 #endif
1363         }
1364       else
1365         {
1366 #ifdef HAVE_TARGET_64_LITTLE
1367           this->sized_write_globals<64, false>(target, sympool, dynpool, of);
1368 #else
1369           gold_unreachable();
1370 #endif
1371         }
1372     }
1373   else
1374     gold_unreachable();
1375 }
1376
1377 // Write out the global symbols.
1378
1379 template<int size, bool big_endian>
1380 void
1381 Symbol_table::sized_write_globals(const Target* target,
1382                                   const Stringpool* sympool,
1383                                   const Stringpool* dynpool,
1384                                   Output_file* of) const
1385 {
1386   const int sym_size = elfcpp::Elf_sizes<size>::sym_size;
1387   unsigned int index = this->first_global_index_;
1388   const off_t oview_size = this->output_count_ * sym_size;
1389   unsigned char* const psyms = of->get_output_view(this->offset_, oview_size);
1390
1391   unsigned int dynamic_count = this->dynamic_count_;
1392   off_t dynamic_size = dynamic_count * sym_size;
1393   unsigned int first_dynamic_global_index = this->first_dynamic_global_index_;
1394   unsigned char* dynamic_view;
1395   if (this->dynamic_offset_ == 0)
1396     dynamic_view = NULL;
1397   else
1398     dynamic_view = of->get_output_view(this->dynamic_offset_, dynamic_size);
1399
1400   unsigned char* ps = psyms;
1401   for (Symbol_table_type::const_iterator p = this->table_.begin();
1402        p != this->table_.end();
1403        ++p)
1404     {
1405       Sized_symbol<size>* sym = static_cast<Sized_symbol<size>*>(p->second);
1406
1407       unsigned int sym_index = sym->symtab_index();
1408       unsigned int dynsym_index;
1409       if (dynamic_view == NULL)
1410         dynsym_index = -1U;
1411       else
1412         dynsym_index = sym->dynsym_index();
1413
1414       if (sym_index == -1U && dynsym_index == -1U)
1415         {
1416           // This symbol is not included in the output file.
1417           continue;
1418         }
1419
1420       if (sym_index == index)
1421         ++index;
1422       else if (sym_index != -1U)
1423         {
1424           // We have already seen this symbol, because it has a
1425           // default version.
1426           gold_assert(sym_index < index);
1427           if (dynsym_index == -1U)
1428             continue;
1429           sym_index = -1U;
1430         }
1431
1432       unsigned int shndx;
1433       typename elfcpp::Elf_types<32>::Elf_Addr value = sym->value();
1434       switch (sym->source())
1435         {
1436         case Symbol::FROM_OBJECT:
1437           {
1438             unsigned int in_shndx = sym->shndx();
1439
1440             // FIXME: We need some target specific support here.
1441             if (in_shndx >= elfcpp::SHN_LORESERVE
1442                 && in_shndx != elfcpp::SHN_ABS)
1443               {
1444                 gold_error(_("%s: unsupported symbol section 0x%x"),
1445                            sym->name(), in_shndx);
1446                 shndx = in_shndx;
1447               }
1448             else
1449               {
1450                 Object* symobj = sym->object();
1451                 if (symobj->is_dynamic())
1452                   {
1453                     if (sym->needs_dynsym_value())
1454                       value = target->dynsym_value(sym);
1455                     shndx = elfcpp::SHN_UNDEF;
1456                   }
1457                 else if (in_shndx == elfcpp::SHN_UNDEF
1458                          || in_shndx == elfcpp::SHN_ABS)
1459                   shndx = in_shndx;
1460                 else
1461                   {
1462                     Relobj* relobj = static_cast<Relobj*>(symobj);
1463                     off_t secoff;
1464                     Output_section* os = relobj->output_section(in_shndx,
1465                                                                 &secoff);
1466                     gold_assert(os != NULL);
1467                     shndx = os->out_shndx();
1468                   }
1469               }
1470           }
1471           break;
1472
1473         case Symbol::IN_OUTPUT_DATA:
1474           shndx = sym->output_data()->out_shndx();
1475           break;
1476
1477         case Symbol::IN_OUTPUT_SEGMENT:
1478           shndx = elfcpp::SHN_ABS;
1479           break;
1480
1481         case Symbol::CONSTANT:
1482           shndx = elfcpp::SHN_ABS;
1483           break;
1484
1485         default:
1486           gold_unreachable();
1487         }
1488
1489       if (sym_index != -1U)
1490         {
1491           this->sized_write_symbol SELECT_SIZE_ENDIAN_NAME(size, big_endian) (
1492               sym, sym->value(), shndx, sympool, ps
1493               SELECT_SIZE_ENDIAN(size, big_endian));
1494           ps += sym_size;
1495         }
1496
1497       if (dynsym_index != -1U)
1498         {
1499           dynsym_index -= first_dynamic_global_index;
1500           gold_assert(dynsym_index < dynamic_count);
1501           unsigned char* pd = dynamic_view + (dynsym_index * sym_size);
1502           this->sized_write_symbol SELECT_SIZE_ENDIAN_NAME(size, big_endian) (
1503               sym, value, shndx, dynpool, pd
1504               SELECT_SIZE_ENDIAN(size, big_endian));
1505         }
1506     }
1507
1508   gold_assert(ps - psyms == oview_size);
1509
1510   of->write_output_view(this->offset_, oview_size, psyms);
1511   if (dynamic_view != NULL)
1512     of->write_output_view(this->dynamic_offset_, dynamic_size, dynamic_view);
1513 }
1514
1515 // Write out the symbol SYM, in section SHNDX, to P.  POOL is the
1516 // strtab holding the name.
1517
1518 template<int size, bool big_endian>
1519 void
1520 Symbol_table::sized_write_symbol(
1521     Sized_symbol<size>* sym,
1522     typename elfcpp::Elf_types<size>::Elf_Addr value,
1523     unsigned int shndx,
1524     const Stringpool* pool,
1525     unsigned char* p
1526     ACCEPT_SIZE_ENDIAN) const
1527 {
1528   elfcpp::Sym_write<size, big_endian> osym(p);
1529   osym.put_st_name(pool->get_offset(sym->name()));
1530   osym.put_st_value(value);
1531   osym.put_st_size(sym->symsize());
1532   osym.put_st_info(elfcpp::elf_st_info(sym->binding(), sym->type()));
1533   osym.put_st_other(elfcpp::elf_st_other(sym->visibility(), sym->nonvis()));
1534   osym.put_st_shndx(shndx);
1535 }
1536
1537 // Write out a section symbol.  Return the update offset.
1538
1539 void
1540 Symbol_table::write_section_symbol(const Output_section *os,
1541                                    Output_file* of,
1542                                    off_t offset) const
1543 {
1544   if (parameters->get_size() == 32)
1545     {
1546       if (parameters->is_big_endian())
1547         {
1548 #ifdef HAVE_TARGET_32_BIG
1549           this->sized_write_section_symbol<32, true>(os, of, offset);
1550 #else
1551           gold_unreachable();
1552 #endif
1553         }
1554       else
1555         {
1556 #ifdef HAVE_TARGET_32_LITTLE
1557           this->sized_write_section_symbol<32, false>(os, of, offset);
1558 #else
1559           gold_unreachable();
1560 #endif
1561         }
1562     }
1563   else if (parameters->get_size() == 64)
1564     {
1565       if (parameters->is_big_endian())
1566         {
1567 #ifdef HAVE_TARGET_64_BIG
1568           this->sized_write_section_symbol<64, true>(os, of, offset);
1569 #else
1570           gold_unreachable();
1571 #endif
1572         }
1573       else
1574         {
1575 #ifdef HAVE_TARGET_64_LITTLE
1576           this->sized_write_section_symbol<64, false>(os, of, offset);
1577 #else
1578           gold_unreachable();
1579 #endif
1580         }
1581     }
1582   else
1583     gold_unreachable();
1584 }
1585
1586 // Write out a section symbol, specialized for size and endianness.
1587
1588 template<int size, bool big_endian>
1589 void
1590 Symbol_table::sized_write_section_symbol(const Output_section* os,
1591                                          Output_file* of,
1592                                          off_t offset) const
1593 {
1594   const int sym_size = elfcpp::Elf_sizes<size>::sym_size;
1595
1596   unsigned char* pov = of->get_output_view(offset, sym_size);
1597
1598   elfcpp::Sym_write<size, big_endian> osym(pov);
1599   osym.put_st_name(0);
1600   osym.put_st_value(os->address());
1601   osym.put_st_size(0);
1602   osym.put_st_info(elfcpp::elf_st_info(elfcpp::STB_LOCAL,
1603                                        elfcpp::STT_SECTION));
1604   osym.put_st_other(elfcpp::elf_st_other(elfcpp::STV_DEFAULT, 0));
1605   osym.put_st_shndx(os->out_shndx());
1606
1607   of->write_output_view(offset, sym_size, pov);
1608 }
1609
1610 // Warnings functions.
1611
1612 // Add a new warning.
1613
1614 void
1615 Warnings::add_warning(Symbol_table* symtab, const char* name, Object* obj,
1616                       unsigned int shndx)
1617 {
1618   name = symtab->canonicalize_name(name);
1619   this->warnings_[name].set(obj, shndx);
1620 }
1621
1622 // Look through the warnings and mark the symbols for which we should
1623 // warn.  This is called during Layout::finalize when we know the
1624 // sources for all the symbols.
1625
1626 void
1627 Warnings::note_warnings(Symbol_table* symtab)
1628 {
1629   for (Warning_table::iterator p = this->warnings_.begin();
1630        p != this->warnings_.end();
1631        ++p)
1632     {
1633       Symbol* sym = symtab->lookup(p->first, NULL);
1634       if (sym != NULL
1635           && sym->source() == Symbol::FROM_OBJECT
1636           && sym->object() == p->second.object)
1637         {
1638           sym->set_has_warning();
1639
1640           // Read the section contents to get the warning text.  It
1641           // would be nicer if we only did this if we have to actually
1642           // issue a warning.  Unfortunately, warnings are issued as
1643           // we relocate sections.  That means that we can not lock
1644           // the object then, as we might try to issue the same
1645           // warning multiple times simultaneously.
1646           {
1647             Task_locker_obj<Object> tl(*p->second.object);
1648             const unsigned char* c;
1649             off_t len;
1650             c = p->second.object->section_contents(p->second.shndx, &len,
1651                                                    false);
1652             p->second.set_text(reinterpret_cast<const char*>(c), len);
1653           }
1654         }
1655     }
1656 }
1657
1658 // Issue a warning.  This is called when we see a relocation against a
1659 // symbol for which has a warning.
1660
1661 template<int size, bool big_endian>
1662 void
1663 Warnings::issue_warning(const Symbol* sym,
1664                         const Relocate_info<size, big_endian>* relinfo,
1665                         size_t relnum, off_t reloffset) const
1666 {
1667   gold_assert(sym->has_warning());
1668   Warning_table::const_iterator p = this->warnings_.find(sym->name());
1669   gold_assert(p != this->warnings_.end());
1670   gold_warning_at_location(relinfo, relnum, reloffset,
1671                            "%s", p->second.text.c_str());
1672 }
1673
1674 // Instantiate the templates we need.  We could use the configure
1675 // script to restrict this to only the ones needed for implemented
1676 // targets.
1677
1678 #ifdef HAVE_TARGET_32_LITTLE
1679 template
1680 void
1681 Symbol_table::add_from_relobj<32, false>(
1682     Sized_relobj<32, false>* relobj,
1683     const unsigned char* syms,
1684     size_t count,
1685     const char* sym_names,
1686     size_t sym_name_size,
1687     Symbol** sympointers);
1688 #endif
1689
1690 #ifdef HAVE_TARGET_32_BIG
1691 template
1692 void
1693 Symbol_table::add_from_relobj<32, true>(
1694     Sized_relobj<32, true>* relobj,
1695     const unsigned char* syms,
1696     size_t count,
1697     const char* sym_names,
1698     size_t sym_name_size,
1699     Symbol** sympointers);
1700 #endif
1701
1702 #ifdef HAVE_TARGET_64_LITTLE
1703 template
1704 void
1705 Symbol_table::add_from_relobj<64, false>(
1706     Sized_relobj<64, false>* relobj,
1707     const unsigned char* syms,
1708     size_t count,
1709     const char* sym_names,
1710     size_t sym_name_size,
1711     Symbol** sympointers);
1712 #endif
1713
1714 #ifdef HAVE_TARGET_64_BIG
1715 template
1716 void
1717 Symbol_table::add_from_relobj<64, true>(
1718     Sized_relobj<64, true>* relobj,
1719     const unsigned char* syms,
1720     size_t count,
1721     const char* sym_names,
1722     size_t sym_name_size,
1723     Symbol** sympointers);
1724 #endif
1725
1726 #ifdef HAVE_TARGET_32_LITTLE
1727 template
1728 void
1729 Symbol_table::add_from_dynobj<32, false>(
1730     Sized_dynobj<32, false>* dynobj,
1731     const unsigned char* syms,
1732     size_t count,
1733     const char* sym_names,
1734     size_t sym_name_size,
1735     const unsigned char* versym,
1736     size_t versym_size,
1737     const std::vector<const char*>* version_map);
1738 #endif
1739
1740 #ifdef HAVE_TARGET_32_BIG
1741 template
1742 void
1743 Symbol_table::add_from_dynobj<32, true>(
1744     Sized_dynobj<32, true>* dynobj,
1745     const unsigned char* syms,
1746     size_t count,
1747     const char* sym_names,
1748     size_t sym_name_size,
1749     const unsigned char* versym,
1750     size_t versym_size,
1751     const std::vector<const char*>* version_map);
1752 #endif
1753
1754 #ifdef HAVE_TARGET_64_LITTLE
1755 template
1756 void
1757 Symbol_table::add_from_dynobj<64, false>(
1758     Sized_dynobj<64, false>* dynobj,
1759     const unsigned char* syms,
1760     size_t count,
1761     const char* sym_names,
1762     size_t sym_name_size,
1763     const unsigned char* versym,
1764     size_t versym_size,
1765     const std::vector<const char*>* version_map);
1766 #endif
1767
1768 #ifdef HAVE_TARGET_64_BIG
1769 template
1770 void
1771 Symbol_table::add_from_dynobj<64, true>(
1772     Sized_dynobj<64, true>* dynobj,
1773     const unsigned char* syms,
1774     size_t count,
1775     const char* sym_names,
1776     size_t sym_name_size,
1777     const unsigned char* versym,
1778     size_t versym_size,
1779     const std::vector<const char*>* version_map);
1780 #endif
1781
1782 #ifdef HAVE_TARGET_32_LITTLE
1783 template
1784 void
1785 Warnings::issue_warning<32, false>(const Symbol* sym,
1786                                    const Relocate_info<32, false>* relinfo,
1787                                    size_t relnum, off_t reloffset) const;
1788 #endif
1789
1790 #ifdef HAVE_TARGET_32_BIG
1791 template
1792 void
1793 Warnings::issue_warning<32, true>(const Symbol* sym,
1794                                   const Relocate_info<32, true>* relinfo,
1795                                   size_t relnum, off_t reloffset) const;
1796 #endif
1797
1798 #ifdef HAVE_TARGET_64_LITTLE
1799 template
1800 void
1801 Warnings::issue_warning<64, false>(const Symbol* sym,
1802                                    const Relocate_info<64, false>* relinfo,
1803                                    size_t relnum, off_t reloffset) const;
1804 #endif
1805
1806 #ifdef HAVE_TARGET_64_BIG
1807 template
1808 void
1809 Warnings::issue_warning<64, true>(const Symbol* sym,
1810                                   const Relocate_info<64, true>* relinfo,
1811                                   size_t relnum, off_t reloffset) const;
1812 #endif
1813
1814
1815 } // End namespace gold.