gold/symtab.cc

   1 // symtab.cc -- the gold symbol table
   2
   3 // Copyright 2006, 2007, 2008, 2009, 2010, 2011 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 <cstring>
  26 #include <stdint.h>
  27 #include <algorithm>
  28 #include <set>
  29 #include <string>
  30 #include <utility>
  31 #include "demangle.h"
  32
  33 #include "gc.h"
  34 #include "object.h"
  35 #include "dwarf_reader.h"
  36 #include "dynobj.h"
  37 #include "output.h"
  38 #include "target.h"
  39 #include "workqueue.h"
  40 #include "symtab.h"
  41 #include "script.h"
  42 #include "plugin.h"
  43 #include "incremental.h"
  44
  45 namespace gold
  46 {
  47
  48 // Class Symbol.
  49
  50 // Initialize fields in Symbol.  This initializes everything except u_
  51 // and source_.
  52
  53 void
  54 Symbol::init_fields(const char* name, const char* version,
  55                     elfcpp::STT type, elfcpp::STB binding,
  56                     elfcpp::STV visibility, unsigned char nonvis)
  57 {
  58   this->name_ = name;
  59   this->version_ = version;
  60   this->symtab_index_ = 0;
  61   this->dynsym_index_ = 0;
  62   this->got_offsets_.init();
  63   this->plt_offset_ = -1U;
  64   this->type_ = type;
  65   this->binding_ = binding;
  66   this->visibility_ = visibility;
  67   this->nonvis_ = nonvis;
  68   this->is_def_ = false;
  69   this->is_forwarder_ = false;
  70   this->has_alias_ = false;
  71   this->needs_dynsym_entry_ = false;
  72   this->in_reg_ = false;
  73   this->in_dyn_ = false;
  74   this->has_warning_ = false;
  75   this->is_copied_from_dynobj_ = false;
  76   this->is_forced_local_ = false;
  77   this->is_ordinary_shndx_ = false;
  78   this->in_real_elf_ = false;
  79   this->is_defined_in_discarded_section_ = false;
  80   this->undef_binding_set_ = false;
  81   this->undef_binding_weak_ = false;
  82 }
  83
  84 // Return the demangled version of the symbol's name, but only
  85 // if the --demangle flag was set.
  86
  87 static std::string
  88 demangle(const char* name)
  89 {
  90   if (!parameters->options().do_demangle())
  91     return name;
  92
  93   // cplus_demangle allocates memory for the result it returns,
  94   // and returns NULL if the name is already demangled.
  95   char* demangled_name = cplus_demangle(name, DMGL_ANSI | DMGL_PARAMS);
  96   if (demangled_name == NULL)
  97     return name;
  98
  99   std::string retval(demangled_name);
 100   free(demangled_name);
 101   return retval;
 102 }
 103
 104 std::string
 105 Symbol::demangled_name() const
 106 {
 107   return demangle(this->name());
 108 }
 109
 110 // Initialize the fields in the base class Symbol for SYM in OBJECT.
 111
 112 template<int size, bool big_endian>
 113 void
 114 Symbol::init_base_object(const char* name, const char* version, Object* object,
 115                          const elfcpp::Sym<size, big_endian>& sym,
 116                          unsigned int st_shndx, bool is_ordinary)
 117 {
 118   this->init_fields(name, version, sym.get_st_type(), sym.get_st_bind(),
 119                     sym.get_st_visibility(), sym.get_st_nonvis());
 120   this->u_.from_object.object = object;
 121   this->u_.from_object.shndx = st_shndx;
 122   this->is_ordinary_shndx_ = is_ordinary;
 123   this->source_ = FROM_OBJECT;
 124   this->in_reg_ = !object->is_dynamic();
 125   this->in_dyn_ = object->is_dynamic();
 126   this->in_real_elf_ = object->pluginobj() == NULL;
 127 }
 128
 129 // Initialize the fields in the base class Symbol for a symbol defined
 130 // in an Output_data.
 131
 132 void
 133 Symbol::init_base_output_data(const char* name, const char* version,
 134                               Output_data* od, elfcpp::STT type,
 135                               elfcpp::STB binding, elfcpp::STV visibility,
 136                               unsigned char nonvis, bool offset_is_from_end)
 137 {
 138   this->init_fields(name, version, type, binding, visibility, nonvis);
 139   this->u_.in_output_data.output_data = od;
 140   this->u_.in_output_data.offset_is_from_end = offset_is_from_end;
 141   this->source_ = IN_OUTPUT_DATA;
 142   this->in_reg_ = true;
 143   this->in_real_elf_ = true;
 144 }
 145
 146 // Initialize the fields in the base class Symbol for a symbol defined
 147 // in an Output_segment.
 148
 149 void
 150 Symbol::init_base_output_segment(const char* name, const char* version,
 151                                  Output_segment* os, elfcpp::STT type,
 152                                  elfcpp::STB binding, elfcpp::STV visibility,
 153                                  unsigned char nonvis,
 154                                  Segment_offset_base offset_base)
 155 {
 156   this->init_fields(name, version, type, binding, visibility, nonvis);
 157   this->u_.in_output_segment.output_segment = os;
 158   this->u_.in_output_segment.offset_base = offset_base;
 159   this->source_ = IN_OUTPUT_SEGMENT;
 160   this->in_reg_ = true;
 161   this->in_real_elf_ = true;
 162 }
 163
 164 // Initialize the fields in the base class Symbol for a symbol defined
 165 // as a constant.
 166
 167 void
 168 Symbol::init_base_constant(const char* name, const char* version,
 169                            elfcpp::STT type, elfcpp::STB binding,
 170                            elfcpp::STV visibility, unsigned char nonvis)
 171 {
 172   this->init_fields(name, version, type, binding, visibility, nonvis);
 173   this->source_ = IS_CONSTANT;
 174   this->in_reg_ = true;
 175   this->in_real_elf_ = true;
 176 }
 177
 178 // Initialize the fields in the base class Symbol for an undefined
 179 // symbol.
 180
 181 void
 182 Symbol::init_base_undefined(const char* name, const char* version,
 183                             elfcpp::STT type, elfcpp::STB binding,
 184                             elfcpp::STV visibility, unsigned char nonvis)
 185 {
 186   this->init_fields(name, version, type, binding, visibility, nonvis);
 187   this->dynsym_index_ = -1U;
 188   this->source_ = IS_UNDEFINED;
 189   this->in_reg_ = true;
 190   this->in_real_elf_ = true;
 191 }
 192
 193 // Allocate a common symbol in the base.
 194
 195 void
 196 Symbol::allocate_base_common(Output_data* od)
 197 {
 198   gold_assert(this->is_common());
 199   this->source_ = IN_OUTPUT_DATA;
 200   this->u_.in_output_data.output_data = od;
 201   this->u_.in_output_data.offset_is_from_end = false;
 202 }
 203
 204 // Initialize the fields in Sized_symbol for SYM in OBJECT.
 205
 206 template<int size>
 207 template<bool big_endian>
 208 void
 209 Sized_symbol<size>::init_object(const char* name, const char* version,
 210                                 Object* object,
 211                                 const elfcpp::Sym<size, big_endian>& sym,
 212                                 unsigned int st_shndx, bool is_ordinary)
 213 {
 214   this->init_base_object(name, version, object, sym, st_shndx, is_ordinary);
 215   this->value_ = sym.get_st_value();
 216   this->symsize_ = sym.get_st_size();
 217 }
 218
 219 // Initialize the fields in Sized_symbol for a symbol defined in an
 220 // Output_data.
 221
 222 template<int size>
 223 void
 224 Sized_symbol<size>::init_output_data(const char* name, const char* version,
 225                                      Output_data* od, Value_type value,
 226                                      Size_type symsize, elfcpp::STT type,
 227                                      elfcpp::STB binding,
 228                                      elfcpp::STV visibility,
 229                                      unsigned char nonvis,
 230                                      bool offset_is_from_end)
 231 {
 232   this->init_base_output_data(name, version, od, type, binding, visibility,
 233                               nonvis, offset_is_from_end);
 234   this->value_ = value;
 235   this->symsize_ = symsize;
 236 }
 237
 238 // Initialize the fields in Sized_symbol for a symbol defined in an
 239 // Output_segment.
 240
 241 template<int size>
 242 void
 243 Sized_symbol<size>::init_output_segment(const char* name, const char* version,
 244                                         Output_segment* os, Value_type value,
 245                                         Size_type symsize, elfcpp::STT type,
 246                                         elfcpp::STB binding,
 247                                         elfcpp::STV visibility,
 248                                         unsigned char nonvis,
 249                                         Segment_offset_base offset_base)
 250 {
 251   this->init_base_output_segment(name, version, os, type, binding, visibility,
 252                                  nonvis, offset_base);
 253   this->value_ = value;
 254   this->symsize_ = symsize;
 255 }
 256
 257 // Initialize the fields in Sized_symbol for a symbol defined as a
 258 // constant.
 259
 260 template<int size>
 261 void
 262 Sized_symbol<size>::init_constant(const char* name, const char* version,
 263                                   Value_type value, Size_type symsize,
 264                                   elfcpp::STT type, elfcpp::STB binding,
 265                                   elfcpp::STV visibility, unsigned char nonvis)
 266 {
 267   this->init_base_constant(name, version, type, binding, visibility, nonvis);
 268   this->value_ = value;
 269   this->symsize_ = symsize;
 270 }
 271
 272 // Initialize the fields in Sized_symbol for an undefined symbol.
 273
 274 template<int size>
 275 void
 276 Sized_symbol<size>::init_undefined(const char* name, const char* version,
 277                                    elfcpp::STT type, elfcpp::STB binding,
 278                                    elfcpp::STV visibility, unsigned char nonvis)
 279 {
 280   this->init_base_undefined(name, version, type, binding, visibility, nonvis);
 281   this->value_ = 0;
 282   this->symsize_ = 0;
 283 }
 284
 285 // Return true if SHNDX represents a common symbol.
 286
 287 bool
 288 Symbol::is_common_shndx(unsigned int shndx)
 289 {
 290   return (shndx == elfcpp::SHN_COMMON
 291           || shndx == parameters->target().small_common_shndx()
 292           || shndx == parameters->target().large_common_shndx());
 293 }
 294
 295 // Allocate a common symbol.
 296
 297 template<int size>
 298 void
 299 Sized_symbol<size>::allocate_common(Output_data* od, Value_type value)
 300 {
 301   this->allocate_base_common(od);
 302   this->value_ = value;
 303 }
 304
 305 // The ""'s around str ensure str is a string literal, so sizeof works.
 306 #define strprefix(var, str)   (strncmp(var, str, sizeof("" str "") - 1) == 0)
 307
 308 // Return true if this symbol should be added to the dynamic symbol
 309 // table.
 310
 311 inline bool
 312 Symbol::should_add_dynsym_entry(Symbol_table* symtab) const
 313 {
 314   // If the symbol is only present on plugin files, the plugin decided we
 315   // don't need it.
 316   if (!this->in_real_elf())
 317     return false;
 318
 319   // If the symbol is used by a dynamic relocation, we need to add it.
 320   if (this->needs_dynsym_entry())
 321     return true;
 322
 323   // If this symbol's section is not added, the symbol need not be added.
 324   // The section may have been GCed.  Note that export_dynamic is being
 325   // overridden here.  This should not be done for shared objects.
 326   if (parameters->options().gc_sections()
 327       && !parameters->options().shared()
 328       && this->source() == Symbol::FROM_OBJECT
 329       && !this->object()->is_dynamic())
 330     {
 331       Relobj* relobj = static_cast<Relobj*>(this->object());
 332       bool is_ordinary;
 333       unsigned int shndx = this->shndx(&is_ordinary);
 334       if (is_ordinary && shndx != elfcpp::SHN_UNDEF
 335           && !relobj->is_section_included(shndx)
 336           && !symtab->is_section_folded(relobj, shndx))
 337         return false;
 338     }
 339
 340   // If the symbol was forced local in a version script, do not add it.
 341   if (this->is_forced_local())
 342     return false;
 343
 344   // If the symbol was forced dynamic in a --dynamic-list file, add it.
 345   if (parameters->options().in_dynamic_list(this->name()))
 346     return true;
 347
 348   // If dynamic-list-data was specified, add any STT_OBJECT.
 349   if (parameters->options().dynamic_list_data()
 350       && !this->is_from_dynobj()
 351       && this->type() == elfcpp::STT_OBJECT)
 352     return true;
 353
 354   // If --dynamic-list-cpp-new was specified, add any new/delete symbol.
 355   // If --dynamic-list-cpp-typeinfo was specified, add any typeinfo symbols.
 356   if ((parameters->options().dynamic_list_cpp_new()
 357        || parameters->options().dynamic_list_cpp_typeinfo())
 358       && !this->is_from_dynobj())
 359     {
 360       // TODO(csilvers): We could probably figure out if we're an operator
 361       //                 new/delete or typeinfo without the need to demangle.
 362       char* demangled_name = cplus_demangle(this->name(),
 363                                             DMGL_ANSI | DMGL_PARAMS);
 364       if (demangled_name == NULL)
 365         {
 366           // Not a C++ symbol, so it can't satisfy these flags
 367         }
 368       else if (parameters->options().dynamic_list_cpp_new()
 369                && (strprefix(demangled_name, "operator new")
 370                    || strprefix(demangled_name, "operator delete")))
 371         {
 372           free(demangled_name);
 373           return true;
 374         }
 375       else if (parameters->options().dynamic_list_cpp_typeinfo()
 376                && (strprefix(demangled_name, "typeinfo name for")
 377                    || strprefix(demangled_name, "typeinfo for")))
 378         {
 379           free(demangled_name);
 380           return true;
 381         }
 382       else
 383         free(demangled_name);
 384     }
 385
 386   // If exporting all symbols or building a shared library,
 387   // and the symbol is defined in a regular object and is
 388   // externally visible, we need to add it.
 389   if ((parameters->options().export_dynamic() || parameters->options().shared())
 390       && !this->is_from_dynobj()
 391       && this->is_externally_visible())
 392     return true;
 393
 394   return false;
 395 }
 396
 397 // Return true if the final value of this symbol is known at link
 398 // time.
 399
 400 bool
 401 Symbol::final_value_is_known() const
 402 {
 403   // If we are not generating an executable, then no final values are
 404   // known, since they will change at runtime.
 405   if (parameters->options().output_is_position_independent()
 406       || parameters->options().relocatable())
 407     return false;
 408
 409   // If the symbol is not from an object file, and is not undefined,
 410   // then it is defined, and known.
 411   if (this->source_ != FROM_OBJECT)
 412     {
 413       if (this->source_ != IS_UNDEFINED)
 414         return true;
 415     }
 416   else
 417     {
 418       // If the symbol is from a dynamic object, then the final value
 419       // is not known.
 420       if (this->object()->is_dynamic())
 421         return false;
 422
 423       // If the symbol is not undefined (it is defined or common),
 424       // then the final value is known.
 425       if (!this->is_undefined())
 426         return true;
 427     }
 428
 429   // If the symbol is undefined, then whether the final value is known
 430   // depends on whether we are doing a static link.  If we are doing a
 431   // dynamic link, then the final value could be filled in at runtime.
 432   // This could reasonably be the case for a weak undefined symbol.
 433   return parameters->doing_static_link();
 434 }
 435
 436 // Return the output section where this symbol is defined.
 437
 438 Output_section*
 439 Symbol::output_section() const
 440 {
 441   switch (this->source_)
 442     {
 443     case FROM_OBJECT:
 444       {
 445         unsigned int shndx = this->u_.from_object.shndx;
 446         if (shndx != elfcpp::SHN_UNDEF && this->is_ordinary_shndx_)
 447           {
 448             gold_assert(!this->u_.from_object.object->is_dynamic());
 449             gold_assert(this->u_.from_object.object->pluginobj() == NULL);
 450             Relobj* relobj = static_cast<Relobj*>(this->u_.from_object.object);
 451             return relobj->output_section(shndx);
 452           }
 453         return NULL;
 454       }
 455
 456     case IN_OUTPUT_DATA:
 457       return this->u_.in_output_data.output_data->output_section();
 458
 459     case IN_OUTPUT_SEGMENT:
 460     case IS_CONSTANT:
 461     case IS_UNDEFINED:
 462       return NULL;
 463
 464     default:
 465       gold_unreachable();
 466     }
 467 }
 468
 469 // Set the symbol's output section.  This is used for symbols defined
 470 // in scripts.  This should only be called after the symbol table has
 471 // been finalized.
 472
 473 void
 474 Symbol::set_output_section(Output_section* os)
 475 {
 476   switch (this->source_)
 477     {
 478     case FROM_OBJECT:
 479     case IN_OUTPUT_DATA:
 480       gold_assert(this->output_section() == os);
 481       break;
 482     case IS_CONSTANT:
 483       this->source_ = IN_OUTPUT_DATA;
 484       this->u_.in_output_data.output_data = os;
 485       this->u_.in_output_data.offset_is_from_end = false;
 486       break;
 487     case IN_OUTPUT_SEGMENT:
 488     case IS_UNDEFINED:
 489     default:
 490       gold_unreachable();
 491     }
 492 }
 493
 494 // Class Symbol_table.
 495
 496 Symbol_table::Symbol_table(unsigned int count,
 497                            const Version_script_info& version_script)
 498   : saw_undefined_(0), offset_(0), table_(count), namepool_(),
 499     forwarders_(), commons_(), tls_commons_(), small_commons_(),
 500     large_commons_(), forced_locals_(), warnings_(),
 501     version_script_(version_script), gc_(NULL), icf_(NULL)
 502 {
 503   namepool_.reserve(count);
 504 }
 505
 506 Symbol_table::~Symbol_table()
 507 {
 508 }
 509
 510 // The symbol table key equality function.  This is called with
 511 // Stringpool keys.
 512
 513 inline bool
 514 Symbol_table::Symbol_table_eq::operator()(const Symbol_table_key& k1,
 515                                           const Symbol_table_key& k2) const
 516 {
 517   return k1.first == k2.first && k1.second == k2.second;
 518 }
 519
 520 bool
 521 Symbol_table::is_section_folded(Object* obj, unsigned int shndx) const
 522 {
 523   return (parameters->options().icf_enabled()
 524           && this->icf_->is_section_folded(obj, shndx));
 525 }
 526
 527 // For symbols that have been listed with -u option, add them to the
 528 // work list to avoid gc'ing them.
 529
 530 void
 531 Symbol_table::gc_mark_undef_symbols(Layout* layout)
 532 {
 533   for (options::String_set::const_iterator p =
 534          parameters->options().undefined_begin();
 535        p != parameters->options().undefined_end();
 536        ++p)
 537     {
 538       const char* name = p->c_str();
 539       Symbol* sym = this->lookup(name);
 540       gold_assert(sym != NULL);
 541       if (sym->source() == Symbol::FROM_OBJECT
 542           && !sym->object()->is_dynamic())
 543         {
 544           Relobj* obj = static_cast<Relobj*>(sym->object());
 545           bool is_ordinary;
 546           unsigned int shndx = sym->shndx(&is_ordinary);
 547           if (is_ordinary)
 548             {
 549               gold_assert(this->gc_ != NULL);
 550               this->gc_->worklist().push(Section_id(obj, shndx));
 551             }
 552         }
 553     }
 554
 555   for (Script_options::referenced_const_iterator p =
 556          layout->script_options()->referenced_begin();
 557        p != layout->script_options()->referenced_end();
 558        ++p)
 559     {
 560       Symbol* sym = this->lookup(p->c_str());
 561       gold_assert(sym != NULL);
 562       if (sym->source() == Symbol::FROM_OBJECT
 563           && !sym->object()->is_dynamic())
 564         {
 565           Relobj* obj = static_cast<Relobj*>(sym->object());
 566           bool is_ordinary;
 567           unsigned int shndx = sym->shndx(&is_ordinary);
 568           if (is_ordinary)
 569             {
 570               gold_assert(this->gc_ != NULL);
 571               this->gc_->worklist().push(Section_id(obj, shndx));
 572             }
 573         }
 574     }
 575 }
 576
 577 void
 578 Symbol_table::gc_mark_symbol_for_shlib(Symbol* sym)
 579 {
 580   if (!sym->is_from_dynobj()
 581       && sym->is_externally_visible())
 582     {
 583       //Add the object and section to the work list.
 584       Relobj* obj = static_cast<Relobj*>(sym->object());
 585       bool is_ordinary;
 586       unsigned int shndx = sym->shndx(&is_ordinary);
 587       if (is_ordinary && shndx != elfcpp::SHN_UNDEF)
 588         {
 589           gold_assert(this->gc_!= NULL);
 590           this->gc_->worklist().push(Section_id(obj, shndx));
 591         }
 592     }
 593 }
 594
 595 // When doing garbage collection, keep symbols that have been seen in
 596 // dynamic objects.
 597 inline void
 598 Symbol_table::gc_mark_dyn_syms(Symbol* sym)
 599 {
 600   if (sym->in_dyn() && sym->source() == Symbol::FROM_OBJECT
 601       && !sym->object()->is_dynamic())
 602     {
 603       Relobj* obj = static_cast<Relobj*>(sym->object());
 604       bool is_ordinary;
 605       unsigned int shndx = sym->shndx(&is_ordinary);
 606       if (is_ordinary && shndx != elfcpp::SHN_UNDEF)
 607         {
 608           gold_assert(this->gc_ != NULL);
 609           this->gc_->worklist().push(Section_id(obj, shndx));
 610         }
 611     }
 612 }
 613
 614 // Make TO a symbol which forwards to FROM.
 615
 616 void
 617 Symbol_table::make_forwarder(Symbol* from, Symbol* to)
 618 {
 619   gold_assert(from != to);
 620   gold_assert(!from->is_forwarder() && !to->is_forwarder());
 621   this->forwarders_[from] = to;
 622   from->set_forwarder();
 623 }
 624
 625 // Resolve the forwards from FROM, returning the real symbol.
 626
 627 Symbol*
 628 Symbol_table::resolve_forwards(const Symbol* from) const
 629 {
 630   gold_assert(from->is_forwarder());
 631   Unordered_map<const Symbol*, Symbol*>::const_iterator p =
 632     this->forwarders_.find(from);
 633   gold_assert(p != this->forwarders_.end());
 634   return p->second;
 635 }
 636
 637 // Look up a symbol by name.
 638
 639 Symbol*
 640 Symbol_table::lookup(const char* name, const char* version) const
 641 {
 642   Stringpool::Key name_key;
 643   name = this->namepool_.find(name, &name_key);
 644   if (name == NULL)
 645     return NULL;
 646
 647   Stringpool::Key version_key = 0;
 648   if (version != NULL)
 649     {
 650       version = this->namepool_.find(version, &version_key);
 651       if (version == NULL)
 652         return NULL;
 653     }
 654
 655   Symbol_table_key key(name_key, version_key);
 656   Symbol_table::Symbol_table_type::const_iterator p = this->table_.find(key);
 657   if (p == this->table_.end())
 658     return NULL;
 659   return p->second;
 660 }
 661
 662 // Resolve a Symbol with another Symbol.  This is only used in the
 663 // unusual case where there are references to both an unversioned
 664 // symbol and a symbol with a version, and we then discover that that
 665 // version is the default version.  Because this is unusual, we do
 666 // this the slow way, by converting back to an ELF symbol.
 667
 668 template<int size, bool big_endian>
 669 void
 670 Symbol_table::resolve(Sized_symbol<size>* to, const Sized_symbol<size>* from)
 671 {
 672   unsigned char buf[elfcpp::Elf_sizes<size>::sym_size];
 673   elfcpp::Sym_write<size, big_endian> esym(buf);
 674   // We don't bother to set the st_name or the st_shndx field.
 675   esym.put_st_value(from->value());
 676   esym.put_st_size(from->symsize());
 677   esym.put_st_info(from->binding(), from->type());
 678   esym.put_st_other(from->visibility(), from->nonvis());
 679   bool is_ordinary;
 680   unsigned int shndx = from->shndx(&is_ordinary);
 681   this->resolve(to, esym.sym(), shndx, is_ordinary, shndx, from->object(),
 682                 from->version());
 683   if (from->in_reg())
 684     to->set_in_reg();
 685   if (from->in_dyn())
 686     to->set_in_dyn();
 687   if (parameters->options().gc_sections())
 688     this->gc_mark_dyn_syms(to);
 689 }
 690
 691 // Record that a symbol is forced to be local by a version script or
 692 // by visibility.
 693
 694 void
 695 Symbol_table::force_local(Symbol* sym)
 696 {
 697   if (!sym->is_defined() && !sym->is_common())
 698     return;
 699   if (sym->is_forced_local())
 700     {
 701       // We already got this one.
 702       return;
 703     }
 704   sym->set_is_forced_local();
 705   this->forced_locals_.push_back(sym);
 706 }
 707
 708 // Adjust NAME for wrapping, and update *NAME_KEY if necessary.  This
 709 // is only called for undefined symbols, when at least one --wrap
 710 // option was used.
 711
 712 const char*
 713 Symbol_table::wrap_symbol(const char* name, Stringpool::Key* name_key)
 714 {
 715   // For some targets, we need to ignore a specific character when
 716   // wrapping, and add it back later.
 717   char prefix = '\0';
 718   if (name[0] == parameters->target().wrap_char())
 719     {
 720       prefix = name[0];
 721       ++name;
 722     }
 723
 724   if (parameters->options().is_wrap(name))
 725     {
 726       // Turn NAME into __wrap_NAME.
 727       std::string s;
 728       if (prefix != '\0')
 729         s += prefix;
 730       s += "__wrap_";
 731       s += name;
 732
 733       // This will give us both the old and new name in NAMEPOOL_, but
 734       // that is OK.  Only the versions we need will wind up in the
 735       // real string table in the output file.
 736       return this->namepool_.add(s.c_str(), true, name_key);
 737     }
 738
 739   const char* const real_prefix = "__real_";
 740   const size_t real_prefix_length = strlen(real_prefix);
 741   if (strncmp(name, real_prefix, real_prefix_length) == 0
 742       && parameters->options().is_wrap(name + real_prefix_length))
 743     {
 744       // Turn __real_NAME into NAME.
 745       std::string s;
 746       if (prefix != '\0')
 747         s += prefix;
 748       s += name + real_prefix_length;
 749       return this->namepool_.add(s.c_str(), true, name_key);
 750     }
 751
 752   return name;
 753 }
 754
 755 // This is called when we see a symbol NAME/VERSION, and the symbol
 756 // already exists in the symbol table, and VERSION is marked as being
 757 // the default version.  SYM is the NAME/VERSION symbol we just added.
 758 // DEFAULT_IS_NEW is true if this is the first time we have seen the
 759 // symbol NAME/NULL.  PDEF points to the entry for NAME/NULL.
 760
 761 template<int size, bool big_endian>
 762 void
 763 Symbol_table::define_default_version(Sized_symbol<size>* sym,
 764                                      bool default_is_new,
 765                                      Symbol_table_type::iterator pdef)
 766 {
 767   if (default_is_new)
 768     {
 769       // This is the first time we have seen NAME/NULL.  Make
 770       // NAME/NULL point to NAME/VERSION, and mark SYM as the default
 771       // version.
 772       pdef->second = sym;
 773       sym->set_is_default();
 774     }
 775   else if (pdef->second == sym)
 776     {
 777       // NAME/NULL already points to NAME/VERSION.  Don't mark the
 778       // symbol as the default if it is not already the default.
 779     }
 780   else
 781     {
 782       // This is the unfortunate case where we already have entries
 783       // for both NAME/VERSION and NAME/NULL.  We now see a symbol
 784       // NAME/VERSION where VERSION is the default version.  We have
 785       // already resolved this new symbol with the existing
 786       // NAME/VERSION symbol.
 787
 788       // It's possible that NAME/NULL and NAME/VERSION are both
 789       // defined in regular objects.  This can only happen if one
 790       // object file defines foo and another defines foo@@ver.  This
 791       // is somewhat obscure, but we call it a multiple definition
 792       // error.
 793
 794       // It's possible that NAME/NULL actually has a version, in which
 795       // case it won't be the same as VERSION.  This happens with
 796       // ver_test_7.so in the testsuite for the symbol t2_2.  We see
 797       // t2_2@@VER2, so we define both t2_2/VER2 and t2_2/NULL.  We
 798       // then see an unadorned t2_2 in an object file and give it
 799       // version VER1 from the version script.  This looks like a
 800       // default definition for VER1, so it looks like we should merge
 801       // t2_2/NULL with t2_2/VER1.  That doesn't make sense, but it's
 802       // not obvious that this is an error, either.  So we just punt.
 803
 804       // If one of the symbols has non-default visibility, and the
 805       // other is defined in a shared object, then they are different
 806       // symbols.
 807
 808       // Otherwise, we just resolve the symbols as though they were
 809       // the same.
 810
 811       if (pdef->second->version() != NULL)
 812         gold_assert(pdef->second->version() != sym->version());
 813       else if (sym->visibility() != elfcpp::STV_DEFAULT
 814                && pdef->second->is_from_dynobj())
 815         ;
 816       else if (pdef->second->visibility() != elfcpp::STV_DEFAULT
 817                && sym->is_from_dynobj())
 818         ;
 819       else
 820         {
 821           const Sized_symbol<size>* symdef;
 822           symdef = this->get_sized_symbol<size>(pdef->second);
 823           Symbol_table::resolve<size, big_endian>(sym, symdef);
 824           this->make_forwarder(pdef->second, sym);
 825           pdef->second = sym;
 826           sym->set_is_default();
 827         }
 828     }
 829 }
 830
 831 // Add one symbol from OBJECT to the symbol table.  NAME is symbol
 832 // name and VERSION is the version; both are canonicalized.  DEF is
 833 // whether this is the default version.  ST_SHNDX is the symbol's
 834 // section index; IS_ORDINARY is whether this is a normal section
 835 // rather than a special code.
 836
 837 // If IS_DEFAULT_VERSION is true, then this is the definition of a
 838 // default version of a symbol.  That means that any lookup of
 839 // NAME/NULL and any lookup of NAME/VERSION should always return the
 840 // same symbol.  This is obvious for references, but in particular we
 841 // want to do this for definitions: overriding NAME/NULL should also
 842 // override NAME/VERSION.  If we don't do that, it would be very hard
 843 // to override functions in a shared library which uses versioning.
 844
 845 // We implement this by simply making both entries in the hash table
 846 // point to the same Symbol structure.  That is easy enough if this is
 847 // the first time we see NAME/NULL or NAME/VERSION, but it is possible
 848 // that we have seen both already, in which case they will both have
 849 // independent entries in the symbol table.  We can't simply change
 850 // the symbol table entry, because we have pointers to the entries
 851 // attached to the object files.  So we mark the entry attached to the
 852 // object file as a forwarder, and record it in the forwarders_ map.
 853 // Note that entries in the hash table will never be marked as
 854 // forwarders.
 855 //
 856 // ORIG_ST_SHNDX and ST_SHNDX are almost always the same.
 857 // ORIG_ST_SHNDX is the section index in the input file, or SHN_UNDEF
 858 // for a special section code.  ST_SHNDX may be modified if the symbol
 859 // is defined in a section being discarded.
 860
 861 template<int size, bool big_endian>
 862 Sized_symbol<size>*
 863 Symbol_table::add_from_object(Object* object,
 864                               const char* name,
 865                               Stringpool::Key name_key,
 866                               const char* version,
 867                               Stringpool::Key version_key,
 868                               bool is_default_version,
 869                               const elfcpp::Sym<size, big_endian>& sym,
 870                               unsigned int st_shndx,
 871                               bool is_ordinary,
 872                               unsigned int orig_st_shndx)
 873 {
 874   // Print a message if this symbol is being traced.
 875   if (parameters->options().is_trace_symbol(name))
 876     {
 877       if (orig_st_shndx == elfcpp::SHN_UNDEF)
 878         gold_info(_("%s: reference to %s"), object->name().c_str(), name);
 879       else
 880         gold_info(_("%s: definition of %s"), object->name().c_str(), name);
 881     }
 882
 883   // For an undefined symbol, we may need to adjust the name using
 884   // --wrap.
 885   if (orig_st_shndx == elfcpp::SHN_UNDEF
 886       && parameters->options().any_wrap())
 887     {
 888       const char* wrap_name = this->wrap_symbol(name, &name_key);
 889       if (wrap_name != name)
 890         {
 891           // If we see a reference to malloc with version GLIBC_2.0,
 892           // and we turn it into a reference to __wrap_malloc, then we
 893           // discard the version number.  Otherwise the user would be
 894           // required to specify the correct version for
 895           // __wrap_malloc.
 896           version = NULL;
 897           version_key = 0;
 898           name = wrap_name;
 899         }
 900     }
 901
 902   Symbol* const snull = NULL;
 903   std::pair<typename Symbol_table_type::iterator, bool> ins =
 904     this->table_.insert(std::make_pair(std::make_pair(name_key, version_key),
 905                                        snull));
 906
 907   std::pair<typename Symbol_table_type::iterator, bool> insdefault =
 908     std::make_pair(this->table_.end(), false);
 909   if (is_default_version)
 910     {
 911       const Stringpool::Key vnull_key = 0;
 912       insdefault = this->table_.insert(std::make_pair(std::make_pair(name_key,
 913                                                                      vnull_key),
 914                                                       snull));
 915     }
 916
 917   // ins.first: an iterator, which is a pointer to a pair.
 918   // ins.first->first: the key (a pair of name and version).
 919   // ins.first->second: the value (Symbol*).
 920   // ins.second: true if new entry was inserted, false if not.
 921
 922   Sized_symbol<size>* ret;
 923   bool was_undefined;
 924   bool was_common;
 925   if (!ins.second)
 926     {
 927       // We already have an entry for NAME/VERSION.
 928       ret = this->get_sized_symbol<size>(ins.first->second);
 929       gold_assert(ret != NULL);
 930
 931       was_undefined = ret->is_undefined();
 932       was_common = ret->is_common();
 933
 934       this->resolve(ret, sym, st_shndx, is_ordinary, orig_st_shndx, object,
 935                     version);
 936       if (parameters->options().gc_sections())
 937         this->gc_mark_dyn_syms(ret);
 938
 939       if (is_default_version)
 940         this->define_default_version<size, big_endian>(ret, insdefault.second,
 941                                                        insdefault.first);
 942     }
 943   else
 944     {
 945       // This is the first time we have seen NAME/VERSION.
 946       gold_assert(ins.first->second == NULL);
 947
 948       if (is_default_version && !insdefault.second)
 949         {
 950           // We already have an entry for NAME/NULL.  If we override
 951           // it, then change it to NAME/VERSION.
 952           ret = this->get_sized_symbol<size>(insdefault.first->second);
 953
 954           was_undefined = ret->is_undefined();
 955           was_common = ret->is_common();
 956
 957           this->resolve(ret, sym, st_shndx, is_ordinary, orig_st_shndx, object,
 958                         version);
 959           if (parameters->options().gc_sections())
 960             this->gc_mark_dyn_syms(ret);
 961           ins.first->second = ret;
 962         }
 963       else
 964         {
 965           was_undefined = false;
 966           was_common = false;
 967
 968           Sized_target<size, big_endian>* target =
 969             parameters->sized_target<size, big_endian>();
 970           if (!target->has_make_symbol())
 971             ret = new Sized_symbol<size>();
 972           else
 973             {
 974               ret = target->make_symbol();
 975               if (ret == NULL)
 976                 {
 977                   // This means that we don't want a symbol table
 978                   // entry after all.
 979                   if (!is_default_version)
 980                     this->table_.erase(ins.first);
 981                   else
 982                     {
 983                       this->table_.erase(insdefault.first);
 984                       // Inserting INSDEFAULT invalidated INS.
 985                       this->table_.erase(std::make_pair(name_key,
 986                                                         version_key));
 987                     }
 988                   return NULL;
 989                 }
 990             }
 991
 992           ret->init_object(name, version, object, sym, st_shndx, is_ordinary);
 993
 994           ins.first->second = ret;
 995           if (is_default_version)
 996             {
 997               // This is the first time we have seen NAME/NULL.  Point
 998               // it at the new entry for NAME/VERSION.
 999               gold_assert(insdefault.second);
1000               insdefault.first->second = ret;
1001             }
1002         }
1003
1004       if (is_default_version)
1005         ret->set_is_default();
1006     }
1007
1008   // Record every time we see a new undefined symbol, to speed up
1009   // archive groups.
1010   if (!was_undefined && ret->is_undefined())
1011     {
1012       ++this->saw_undefined_;
1013       if (parameters->options().has_plugins())
1014         parameters->options().plugins()->new_undefined_symbol(ret);
1015     }
1016
1017   // Keep track of common symbols, to speed up common symbol
1018   // allocation.
1019   if (!was_common && ret->is_common())
1020     {
1021       if (ret->type() == elfcpp::STT_TLS)
1022         this->tls_commons_.push_back(ret);
1023       else if (!is_ordinary
1024                && st_shndx == parameters->target().small_common_shndx())
1025         this->small_commons_.push_back(ret);
1026       else if (!is_ordinary
1027                && st_shndx == parameters->target().large_common_shndx())
1028         this->large_commons_.push_back(ret);
1029       else
1030         this->commons_.push_back(ret);
1031     }
1032
1033   // If we're not doing a relocatable link, then any symbol with
1034   // hidden or internal visibility is local.
1035   if ((ret->visibility() == elfcpp::STV_HIDDEN
1036        || ret->visibility() == elfcpp::STV_INTERNAL)
1037       && (ret->binding() == elfcpp::STB_GLOBAL
1038           || ret->binding() == elfcpp::STB_GNU_UNIQUE
1039           || ret->binding() == elfcpp::STB_WEAK)
1040       && !parameters->options().relocatable())
1041     this->force_local(ret);
1042
1043   return ret;
1044 }
1045
1046 // Add all the symbols in a relocatable object to the hash table.
1047
1048 template<int size, bool big_endian>
1049 void
1050 Symbol_table::add_from_relobj(
1051     Sized_relobj<size, big_endian>* relobj,
1052     const unsigned char* syms,
1053     size_t count,
1054     size_t symndx_offset,
1055     const char* sym_names,
1056     size_t sym_name_size,
1057     typename Sized_relobj<size, big_endian>::Symbols* sympointers,
1058     size_t* defined)
1059 {
1060   *defined = 0;
1061
1062   gold_assert(size == parameters->target().get_size());
1063
1064   const int sym_size = elfcpp::Elf_sizes<size>::sym_size;
1065
1066   const bool just_symbols = relobj->just_symbols();
1067
1068   const unsigned char* p = syms;
1069   for (size_t i = 0; i < count; ++i, p += sym_size)
1070     {
1071       (*sympointers)[i] = NULL;
1072
1073       elfcpp::Sym<size, big_endian> sym(p);
1074
1075       unsigned int st_name = sym.get_st_name();
1076       if (st_name >= sym_name_size)
1077         {
1078           relobj->error(_("bad global symbol name offset %u at %zu"),
1079                         st_name, i);
1080           continue;
1081         }
1082
1083       const char* name = sym_names + st_name;
1084
1085       bool is_ordinary;
1086       unsigned int st_shndx = relobj->adjust_sym_shndx(i + symndx_offset,
1087                                                        sym.get_st_shndx(),
1088                                                        &is_ordinary);
1089       unsigned int orig_st_shndx = st_shndx;
1090       if (!is_ordinary)
1091         orig_st_shndx = elfcpp::SHN_UNDEF;
1092
1093       if (st_shndx != elfcpp::SHN_UNDEF)
1094         ++*defined;
1095
1096       // A symbol defined in a section which we are not including must
1097       // be treated as an undefined symbol.
1098       bool is_defined_in_discarded_section = false;
1099       if (st_shndx != elfcpp::SHN_UNDEF
1100           && is_ordinary
1101           && !relobj->is_section_included(st_shndx)
1102           && !this->is_section_folded(relobj, st_shndx))
1103         {
1104           st_shndx = elfcpp::SHN_UNDEF;
1105           is_defined_in_discarded_section = true;
1106         }
1107
1108       // In an object file, an '@' in the name separates the symbol
1109       // name from the version name.  If there are two '@' characters,
1110       // this is the default version.
1111       const char* ver = strchr(name, '@');
1112       Stringpool::Key ver_key = 0;
1113       int namelen = 0;
1114       // IS_DEFAULT_VERSION: is the version default?
1115       // IS_FORCED_LOCAL: is the symbol forced local?
1116       bool is_default_version = false;
1117       bool is_forced_local = false;
1118
1119       if (ver != NULL)
1120         {
1121           // The symbol name is of the form foo@VERSION or foo@@VERSION
1122           namelen = ver - name;
1123           ++ver;
1124           if (*ver == '@')
1125             {
1126               is_default_version = true;
1127               ++ver;
1128             }
1129           ver = this->namepool_.add(ver, true, &ver_key);
1130         }
1131       // We don't want to assign a version to an undefined symbol,
1132       // even if it is listed in the version script.  FIXME: What
1133       // about a common symbol?
1134       else
1135         {
1136           namelen = strlen(name);
1137           if (!this->version_script_.empty()
1138               && st_shndx != elfcpp::SHN_UNDEF)
1139             {
1140               // The symbol name did not have a version, but the
1141               // version script may assign a version anyway.
1142               std::string version;
1143               bool is_global;
1144               if (this->version_script_.get_symbol_version(name, &version,
1145                                                            &is_global))
1146                 {
1147                   if (!is_global)
1148                     is_forced_local = true;
1149                   else if (!version.empty())
1150                     {
1151                       ver = this->namepool_.add_with_length(version.c_str(),
1152                                                             version.length(),
1153                                                             true,
1154                                                             &ver_key);
1155                       is_default_version = true;
1156                     }
1157                 }
1158             }
1159         }
1160
1161       elfcpp::Sym<size, big_endian>* psym = &sym;
1162       unsigned char symbuf[sym_size];
1163       elfcpp::Sym<size, big_endian> sym2(symbuf);
1164       if (just_symbols)
1165         {
1166           memcpy(symbuf, p, sym_size);
1167           elfcpp::Sym_write<size, big_endian> sw(symbuf);
1168           if (orig_st_shndx != elfcpp::SHN_UNDEF && is_ordinary)
1169             {
1170               // Symbol values in object files are section relative.
1171               // This is normally what we want, but since here we are
1172               // converting the symbol to absolute we need to add the
1173               // section address.  The section address in an object
1174               // file is normally zero, but people can use a linker
1175               // script to change it.
1176               sw.put_st_value(sym.get_st_value()
1177                               + relobj->section_address(orig_st_shndx));
1178             }
1179           st_shndx = elfcpp::SHN_ABS;
1180           is_ordinary = false;
1181           psym = &sym2;
1182         }
1183
1184       // Fix up visibility if object has no-export set.
1185       if (relobj->no_export()
1186           && (orig_st_shndx != elfcpp::SHN_UNDEF || !is_ordinary))
1187         {
1188           // We may have copied symbol already above.
1189           if (psym != &sym2)
1190             {
1191               memcpy(symbuf, p, sym_size);
1192               psym = &sym2;
1193             }
1194
1195           elfcpp::STV visibility = sym2.get_st_visibility();
1196           if (visibility == elfcpp::STV_DEFAULT
1197               || visibility == elfcpp::STV_PROTECTED)
1198             {
1199               elfcpp::Sym_write<size, big_endian> sw(symbuf);
1200               unsigned char nonvis = sym2.get_st_nonvis();
1201               sw.put_st_other(elfcpp::STV_HIDDEN, nonvis);
1202             }
1203         }
1204
1205       Stringpool::Key name_key;
1206       name = this->namepool_.add_with_length(name, namelen, true,
1207                                              &name_key);
1208
1209       Sized_symbol<size>* res;
1210       res = this->add_from_object(relobj, name, name_key, ver, ver_key,
1211                                   is_default_version, *psym, st_shndx,
1212                                   is_ordinary, orig_st_shndx);
1213
1214       // If building a shared library using garbage collection, do not
1215       // treat externally visible symbols as garbage.
1216       if (parameters->options().gc_sections()
1217           && parameters->options().shared())
1218         this->gc_mark_symbol_for_shlib(res);
1219
1220       if (is_forced_local)
1221         this->force_local(res);
1222
1223       if (is_defined_in_discarded_section)
1224         res->set_is_defined_in_discarded_section();
1225
1226       (*sympointers)[i] = res;
1227     }
1228 }
1229
1230 // Add a symbol from a plugin-claimed file.
1231
1232 template<int size, bool big_endian>
1233 Symbol*
1234 Symbol_table::add_from_pluginobj(
1235     Sized_pluginobj<size, big_endian>* obj,
1236     const char* name,
1237     const char* ver,
1238     elfcpp::Sym<size, big_endian>* sym)
1239 {
1240   unsigned int st_shndx = sym->get_st_shndx();
1241   bool is_ordinary = st_shndx < elfcpp::SHN_LORESERVE;
1242
1243   Stringpool::Key ver_key = 0;
1244   bool is_default_version = false;
1245   bool is_forced_local = false;
1246
1247   if (ver != NULL)
1248     {
1249       ver = this->namepool_.add(ver, true, &ver_key);
1250     }
1251   // We don't want to assign a version to an undefined symbol,
1252   // even if it is listed in the version script.  FIXME: What
1253   // about a common symbol?
1254   else
1255     {
1256       if (!this->version_script_.empty()
1257           && st_shndx != elfcpp::SHN_UNDEF)
1258         {
1259           // The symbol name did not have a version, but the
1260           // version script may assign a version anyway.
1261           std::string version;
1262           bool is_global;
1263           if (this->version_script_.get_symbol_version(name, &version,
1264                                                        &is_global))
1265             {
1266               if (!is_global)
1267                 is_forced_local = true;
1268               else if (!version.empty())
1269                 {
1270                   ver = this->namepool_.add_with_length(version.c_str(),
1271                                                         version.length(),
1272                                                         true,
1273                                                         &ver_key);
1274                   is_default_version = true;
1275                 }
1276             }
1277         }
1278     }
1279
1280   Stringpool::Key name_key;
1281   name = this->namepool_.add(name, true, &name_key);
1282
1283   Sized_symbol<size>* res;
1284   res = this->add_from_object(obj, name, name_key, ver, ver_key,
1285                               is_default_version, *sym, st_shndx,
1286                               is_ordinary, st_shndx);
1287
1288   if (is_forced_local)
1289     this->force_local(res);
1290
1291   return res;
1292 }
1293
1294 // Add all the symbols in a dynamic object to the hash table.
1295
1296 template<int size, bool big_endian>
1297 void
1298 Symbol_table::add_from_dynobj(
1299     Sized_dynobj<size, big_endian>* dynobj,
1300     const unsigned char* syms,
1301     size_t count,
1302     const char* sym_names,
1303     size_t sym_name_size,
1304     const unsigned char* versym,
1305     size_t versym_size,
1306     const std::vector<const char*>* version_map,
1307     typename Sized_relobj<size, big_endian>::Symbols* sympointers,
1308     size_t* defined)
1309 {
1310   *defined = 0;
1311
1312   gold_assert(size == parameters->target().get_size());
1313
1314   if (dynobj->just_symbols())
1315     {
1316       gold_error(_("--just-symbols does not make sense with a shared object"));
1317       return;
1318     }
1319
1320   if (versym != NULL && versym_size / 2 < count)
1321     {
1322       dynobj->error(_("too few symbol versions"));
1323       return;
1324     }
1325
1326   const int sym_size = elfcpp::Elf_sizes<size>::sym_size;
1327
1328   // We keep a list of all STT_OBJECT symbols, so that we can resolve
1329   // weak aliases.  This is necessary because if the dynamic object
1330   // provides the same variable under two names, one of which is a
1331   // weak definition, and the regular object refers to the weak
1332   // definition, we have to put both the weak definition and the
1333   // strong definition into the dynamic symbol table.  Given a weak
1334   // definition, the only way that we can find the corresponding
1335   // strong definition, if any, is to search the symbol table.
1336   std::vector<Sized_symbol<size>*> object_symbols;
1337
1338   const unsigned char* p = syms;
1339   const unsigned char* vs = versym;
1340   for (size_t i = 0; i < count; ++i, p += sym_size, vs += 2)
1341     {
1342       elfcpp::Sym<size, big_endian> sym(p);
1343
1344       if (sympointers != NULL)
1345         (*sympointers)[i] = NULL;
1346
1347       // Ignore symbols with local binding or that have
1348       // internal or hidden visibility.
1349       if (sym.get_st_bind() == elfcpp::STB_LOCAL
1350           || sym.get_st_visibility() == elfcpp::STV_INTERNAL
1351           || sym.get_st_visibility() == elfcpp::STV_HIDDEN)
1352         continue;
1353
1354       // A protected symbol in a shared library must be treated as a
1355       // normal symbol when viewed from outside the shared library.
1356       // Implement this by overriding the visibility here.
1357       elfcpp::Sym<size, big_endian>* psym = &sym;
1358       unsigned char symbuf[sym_size];
1359       elfcpp::Sym<size, big_endian> sym2(symbuf);
1360       if (sym.get_st_visibility() == elfcpp::STV_PROTECTED)
1361         {
1362           memcpy(symbuf, p, sym_size);
1363           elfcpp::Sym_write<size, big_endian> sw(symbuf);
1364           sw.put_st_other(elfcpp::STV_DEFAULT, sym.get_st_nonvis());
1365           psym = &sym2;
1366         }
1367
1368       unsigned int st_name = psym->get_st_name();
1369       if (st_name >= sym_name_size)
1370         {
1371           dynobj->error(_("bad symbol name offset %u at %zu"),
1372                         st_name, i);
1373           continue;
1374         }
1375
1376       const char* name = sym_names + st_name;
1377
1378       bool is_ordinary;
1379       unsigned int st_shndx = dynobj->adjust_sym_shndx(i, psym->get_st_shndx(),
1380                                                        &is_ordinary);
1381
1382       if (st_shndx != elfcpp::SHN_UNDEF)
1383         ++*defined;
1384
1385       Sized_symbol<size>* res;
1386
1387       if (versym == NULL)
1388         {
1389           Stringpool::Key name_key;
1390           name = this->namepool_.add(name, true, &name_key);
1391           res = this->add_from_object(dynobj, name, name_key, NULL, 0,
1392                                       false, *psym, st_shndx, is_ordinary,
1393                                       st_shndx);
1394         }
1395       else
1396         {
1397           // Read the version information.
1398
1399           unsigned int v = elfcpp::Swap<16, big_endian>::readval(vs);
1400
1401           bool hidden = (v & elfcpp::VERSYM_HIDDEN) != 0;
1402           v &= elfcpp::VERSYM_VERSION;
1403
1404           // The Sun documentation says that V can be VER_NDX_LOCAL,
1405           // or VER_NDX_GLOBAL, or a version index.  The meaning of
1406           // VER_NDX_LOCAL is defined as "Symbol has local scope."
1407           // The old GNU linker will happily generate VER_NDX_LOCAL
1408           // for an undefined symbol.  I don't know what the Sun
1409           // linker will generate.
1410
1411           if (v == static_cast<unsigned int>(elfcpp::VER_NDX_LOCAL)
1412               && st_shndx != elfcpp::SHN_UNDEF)
1413             {
1414               // This symbol should not be visible outside the object.
1415               continue;
1416             }
1417
1418           // At this point we are definitely going to add this symbol.
1419           Stringpool::Key name_key;
1420           name = this->namepool_.add(name, true, &name_key);
1421
1422           if (v == static_cast<unsigned int>(elfcpp::VER_NDX_LOCAL)
1423               || v == static_cast<unsigned int>(elfcpp::VER_NDX_GLOBAL))
1424             {
1425               // This symbol does not have a version.
1426               res = this->add_from_object(dynobj, name, name_key, NULL, 0,
1427                                           false, *psym, st_shndx, is_ordinary,
1428                                           st_shndx);
1429             }
1430           else
1431             {
1432               if (v >= version_map->size())
1433                 {
1434                   dynobj->error(_("versym for symbol %zu out of range: %u"),
1435                                 i, v);
1436                   continue;
1437                 }
1438
1439               const char* version = (*version_map)[v];
1440               if (version == NULL)
1441                 {
1442                   dynobj->error(_("versym for symbol %zu has no name: %u"),
1443                                 i, v);
1444                   continue;
1445                 }
1446
1447               Stringpool::Key version_key;
1448               version = this->namepool_.add(version, true, &version_key);
1449
1450               // If this is an absolute symbol, and the version name
1451               // and symbol name are the same, then this is the
1452               // version definition symbol.  These symbols exist to
1453               // support using -u to pull in particular versions.  We
1454               // do not want to record a version for them.
1455               if (st_shndx == elfcpp::SHN_ABS
1456                   && !is_ordinary
1457                   && name_key == version_key)
1458                 res = this->add_from_object(dynobj, name, name_key, NULL, 0,
1459                                             false, *psym, st_shndx, is_ordinary,
1460                                             st_shndx);
1461               else
1462                 {
1463                   const bool is_default_version =
1464                     !hidden && st_shndx != elfcpp::SHN_UNDEF;
1465                   res = this->add_from_object(dynobj, name, name_key, version,
1466                                               version_key, is_default_version,
1467                                               *psym, st_shndx,
1468                                               is_ordinary, st_shndx);
1469                 }
1470             }
1471         }
1472
1473       // Note that it is possible that RES was overridden by an
1474       // earlier object, in which case it can't be aliased here.
1475       if (st_shndx != elfcpp::SHN_UNDEF
1476           && is_ordinary
1477           && psym->get_st_type() == elfcpp::STT_OBJECT
1478           && res->source() == Symbol::FROM_OBJECT
1479           && res->object() == dynobj)
1480         object_symbols.push_back(res);
1481
1482       if (sympointers != NULL)
1483         (*sympointers)[i] = res;
1484     }
1485
1486   this->record_weak_aliases(&object_symbols);
1487 }
1488
1489 // Add a symbol from a incremental object file.
1490
1491 template<int size, bool big_endian>
1492 Symbol*
1493 Symbol_table::add_from_incrobj(
1494     Object* obj,
1495     const char* name,
1496     const char* ver,
1497     elfcpp::Sym<size, big_endian>* sym)
1498 {
1499   unsigned int st_shndx = sym->get_st_shndx();
1500   bool is_ordinary = st_shndx < elfcpp::SHN_LORESERVE;
1501
1502   Stringpool::Key ver_key = 0;
1503   bool is_default_version = false;
1504   bool is_forced_local = false;
1505
1506   Stringpool::Key name_key;
1507   name = this->namepool_.add(name, true, &name_key);
1508
1509   Sized_symbol<size>* res;
1510   res = this->add_from_object(obj, name, name_key, ver, ver_key,
1511                               is_default_version, *sym, st_shndx,
1512                               is_ordinary, st_shndx);
1513
1514   if (is_forced_local)
1515     this->force_local(res);
1516
1517   return res;
1518 }
1519
1520 // This is used to sort weak aliases.  We sort them first by section
1521 // index, then by offset, then by weak ahead of strong.
1522
1523 template<int size>
1524 class Weak_alias_sorter
1525 {
1526  public:
1527   bool operator()(const Sized_symbol<size>*, const Sized_symbol<size>*) const;
1528 };
1529
1530 template<int size>
1531 bool
1532 Weak_alias_sorter<size>::operator()(const Sized_symbol<size>* s1,
1533                                     const Sized_symbol<size>* s2) const
1534 {
1535   bool is_ordinary;
1536   unsigned int s1_shndx = s1->shndx(&is_ordinary);
1537   gold_assert(is_ordinary);
1538   unsigned int s2_shndx = s2->shndx(&is_ordinary);
1539   gold_assert(is_ordinary);
1540   if (s1_shndx != s2_shndx)
1541     return s1_shndx < s2_shndx;
1542
1543   if (s1->value() != s2->value())
1544     return s1->value() < s2->value();
1545   if (s1->binding() != s2->binding())
1546     {
1547       if (s1->binding() == elfcpp::STB_WEAK)
1548         return true;
1549       if (s2->binding() == elfcpp::STB_WEAK)
1550         return false;
1551     }
1552   return std::string(s1->name()) < std::string(s2->name());
1553 }
1554
1555 // SYMBOLS is a list of object symbols from a dynamic object.  Look
1556 // for any weak aliases, and record them so that if we add the weak
1557 // alias to the dynamic symbol table, we also add the corresponding
1558 // strong symbol.
1559
1560 template<int size>
1561 void
1562 Symbol_table::record_weak_aliases(std::vector<Sized_symbol<size>*>* symbols)
1563 {
1564   // Sort the vector by section index, then by offset, then by weak
1565   // ahead of strong.
1566   std::sort(symbols->begin(), symbols->end(), Weak_alias_sorter<size>());
1567
1568   // Walk through the vector.  For each weak definition, record
1569   // aliases.
1570   for (typename std::vector<Sized_symbol<size>*>::const_iterator p =
1571          symbols->begin();
1572        p != symbols->end();
1573        ++p)
1574     {
1575       if ((*p)->binding() != elfcpp::STB_WEAK)
1576         continue;
1577
1578       // Build a circular list of weak aliases.  Each symbol points to
1579       // the next one in the circular list.
1580
1581       Sized_symbol<size>* from_sym = *p;
1582       typename std::vector<Sized_symbol<size>*>::const_iterator q;
1583       for (q = p + 1; q != symbols->end(); ++q)
1584         {
1585           bool dummy;
1586           if ((*q)->shndx(&dummy) != from_sym->shndx(&dummy)
1587               || (*q)->value() != from_sym->value())
1588             break;
1589
1590           this->weak_aliases_[from_sym] = *q;
1591           from_sym->set_has_alias();
1592           from_sym = *q;
1593         }
1594
1595       if (from_sym != *p)
1596         {
1597           this->weak_aliases_[from_sym] = *p;
1598           from_sym->set_has_alias();
1599         }
1600
1601       p = q - 1;
1602     }
1603 }
1604
1605 // Create and return a specially defined symbol.  If ONLY_IF_REF is
1606 // true, then only create the symbol if there is a reference to it.
1607 // If this does not return NULL, it sets *POLDSYM to the existing
1608 // symbol if there is one.  This sets *RESOLVE_OLDSYM if we should
1609 // resolve the newly created symbol to the old one.  This
1610 // canonicalizes *PNAME and *PVERSION.
1611
1612 template<int size, bool big_endian>
1613 Sized_symbol<size>*
1614 Symbol_table::define_special_symbol(const char** pname, const char** pversion,
1615                                     bool only_if_ref,
1616                                     Sized_symbol<size>** poldsym,
1617                                     bool* resolve_oldsym)
1618 {
1619   *resolve_oldsym = false;
1620
1621   // If the caller didn't give us a version, see if we get one from
1622   // the version script.
1623   std::string v;
1624   bool is_default_version = false;
1625   if (*pversion == NULL)
1626     {
1627       bool is_global;
1628       if (this->version_script_.get_symbol_version(*pname, &v, &is_global))
1629         {
1630           if (is_global && !v.empty())
1631             {
1632               *pversion = v.c_str();
1633               // If we get the version from a version script, then we
1634               // are also the default version.
1635               is_default_version = true;
1636             }
1637         }
1638     }
1639
1640   Symbol* oldsym;
1641   Sized_symbol<size>* sym;
1642
1643   bool add_to_table = false;
1644   typename Symbol_table_type::iterator add_loc = this->table_.end();
1645   bool add_def_to_table = false;
1646   typename Symbol_table_type::iterator add_def_loc = this->table_.end();
1647
1648   if (only_if_ref)
1649     {
1650       oldsym = this->lookup(*pname, *pversion);
1651       if (oldsym == NULL && is_default_version)
1652         oldsym = this->lookup(*pname, NULL);
1653       if (oldsym == NULL || !oldsym->is_undefined())
1654         return NULL;
1655
1656       *pname = oldsym->name();
1657       if (!is_default_version)
1658         *pversion = oldsym->version();
1659     }
1660   else
1661     {
1662       // Canonicalize NAME and VERSION.
1663       Stringpool::Key name_key;
1664       *pname = this->namepool_.add(*pname, true, &name_key);
1665
1666       Stringpool::Key version_key = 0;
1667       if (*pversion != NULL)
1668         *pversion = this->namepool_.add(*pversion, true, &version_key);
1669
1670       Symbol* const snull = NULL;
1671       std::pair<typename Symbol_table_type::iterator, bool> ins =
1672         this->table_.insert(std::make_pair(std::make_pair(name_key,
1673                                                           version_key),
1674                                            snull));
1675
1676       std::pair<typename Symbol_table_type::iterator, bool> insdefault =
1677         std::make_pair(this->table_.end(), false);
1678       if (is_default_version)
1679         {
1680           const Stringpool::Key vnull = 0;
1681           insdefault =
1682             this->table_.insert(std::make_pair(std::make_pair(name_key,
1683                                                               vnull),
1684                                                snull));
1685         }
1686
1687       if (!ins.second)
1688         {
1689           // We already have a symbol table entry for NAME/VERSION.
1690           oldsym = ins.first->second;
1691           gold_assert(oldsym != NULL);
1692
1693           if (is_default_version)
1694             {
1695               Sized_symbol<size>* soldsym =
1696                 this->get_sized_symbol<size>(oldsym);
1697               this->define_default_version<size, big_endian>(soldsym,
1698                                                              insdefault.second,
1699                                                              insdefault.first);
1700             }
1701         }
1702       else
1703         {
1704           // We haven't seen this symbol before.
1705           gold_assert(ins.first->second == NULL);
1706
1707           add_to_table = true;
1708           add_loc = ins.first;
1709
1710           if (is_default_version && !insdefault.second)
1711             {
1712               // We are adding NAME/VERSION, and it is the default
1713               // version.  We already have an entry for NAME/NULL.
1714               oldsym = insdefault.first->second;
1715               *resolve_oldsym = true;
1716             }
1717           else
1718             {
1719               oldsym = NULL;
1720
1721               if (is_default_version)
1722                 {
1723                   add_def_to_table = true;
1724                   add_def_loc = insdefault.first;
1725                 }
1726             }
1727         }
1728     }
1729
1730   const Target& target = parameters->target();
1731   if (!target.has_make_symbol())
1732     sym = new Sized_symbol<size>();
1733   else
1734     {
1735       Sized_target<size, big_endian>* sized_target =
1736         parameters->sized_target<size, big_endian>();
1737       sym = sized_target->make_symbol();
1738       if (sym == NULL)
1739         return NULL;
1740     }
1741
1742   if (add_to_table)
1743     add_loc->second = sym;
1744   else
1745     gold_assert(oldsym != NULL);
1746
1747   if (add_def_to_table)
1748     add_def_loc->second = sym;
1749
1750   *poldsym = this->get_sized_symbol<size>(oldsym);
1751
1752   return sym;
1753 }
1754
1755 // Define a symbol based on an Output_data.
1756
1757 Symbol*
1758 Symbol_table::define_in_output_data(const char* name,
1759                                     const char* version,
1760                                     Defined defined,
1761                                     Output_data* od,
1762                                     uint64_t value,
1763                                     uint64_t symsize,
1764                                     elfcpp::STT type,
1765                                     elfcpp::STB binding,
1766                                     elfcpp::STV visibility,
1767                                     unsigned char nonvis,
1768                                     bool offset_is_from_end,
1769                                     bool only_if_ref)
1770 {
1771   if (parameters->target().get_size() == 32)
1772     {
1773 #if defined(HAVE_TARGET_32_LITTLE) || defined(HAVE_TARGET_32_BIG)
1774       return this->do_define_in_output_data<32>(name, version, defined, od,
1775                                                 value, symsize, type, binding,
1776                                                 visibility, nonvis,
1777                                                 offset_is_from_end,
1778                                                 only_if_ref);
1779 #else
1780       gold_unreachable();
1781 #endif
1782     }
1783   else if (parameters->target().get_size() == 64)
1784     {
1785 #if defined(HAVE_TARGET_64_LITTLE) || defined(HAVE_TARGET_64_BIG)
1786       return this->do_define_in_output_data<64>(name, version, defined, od,
1787                                                 value, symsize, type, binding,
1788                                                 visibility, nonvis,
1789                                                 offset_is_from_end,
1790                                                 only_if_ref);
1791 #else
1792       gold_unreachable();
1793 #endif
1794     }
1795   else
1796     gold_unreachable();
1797 }
1798
1799 // Define a symbol in an Output_data, sized version.
1800
1801 template<int size>
1802 Sized_symbol<size>*
1803 Symbol_table::do_define_in_output_data(
1804     const char* name,
1805     const char* version,
1806     Defined defined,
1807     Output_data* od,
1808     typename elfcpp::Elf_types<size>::Elf_Addr value,
1809     typename elfcpp::Elf_types<size>::Elf_WXword symsize,
1810     elfcpp::STT type,
1811     elfcpp::STB binding,
1812     elfcpp::STV visibility,
1813     unsigned char nonvis,
1814     bool offset_is_from_end,
1815     bool only_if_ref)
1816 {
1817   Sized_symbol<size>* sym;
1818   Sized_symbol<size>* oldsym;
1819   bool resolve_oldsym;
1820
1821   if (parameters->target().is_big_endian())
1822     {
1823 #if defined(HAVE_TARGET_32_BIG) || defined(HAVE_TARGET_64_BIG)
1824       sym = this->define_special_symbol<size, true>(&name, &version,
1825                                                     only_if_ref, &oldsym,
1826                                                     &resolve_oldsym);
1827 #else
1828       gold_unreachable();
1829 #endif
1830     }
1831   else
1832     {
1833 #if defined(HAVE_TARGET_32_LITTLE) || defined(HAVE_TARGET_64_LITTLE)
1834       sym = this->define_special_symbol<size, false>(&name, &version,
1835                                                      only_if_ref, &oldsym,
1836                                                      &resolve_oldsym);
1837 #else
1838       gold_unreachable();
1839 #endif
1840     }
1841
1842   if (sym == NULL)
1843     return NULL;
1844
1845   sym->init_output_data(name, version, od, value, symsize, type, binding,
1846                         visibility, nonvis, offset_is_from_end);
1847
1848   if (oldsym == NULL)
1849     {
1850       if (binding == elfcpp::STB_LOCAL
1851           || this->version_script_.symbol_is_local(name))
1852         this->force_local(sym);
1853       else if (version != NULL)
1854         sym->set_is_default();
1855       return sym;
1856     }
1857
1858   if (Symbol_table::should_override_with_special(oldsym, defined))
1859     this->override_with_special(oldsym, sym);
1860
1861   if (resolve_oldsym)
1862     return sym;
1863   else
1864     {
1865       delete sym;
1866       return oldsym;
1867     }
1868 }
1869
1870 // Define a symbol based on an Output_segment.
1871
1872 Symbol*
1873 Symbol_table::define_in_output_segment(const char* name,
1874                                        const char* version,
1875                                        Defined defined,
1876                                        Output_segment* os,
1877                                        uint64_t value,
1878                                        uint64_t symsize,
1879                                        elfcpp::STT type,
1880                                        elfcpp::STB binding,
1881                                        elfcpp::STV visibility,
1882                                        unsigned char nonvis,
1883                                        Symbol::Segment_offset_base offset_base,
1884                                        bool only_if_ref)
1885 {
1886   if (parameters->target().get_size() == 32)
1887     {
1888 #if defined(HAVE_TARGET_32_LITTLE) || defined(HAVE_TARGET_32_BIG)
1889       return this->do_define_in_output_segment<32>(name, version, defined, os,
1890                                                    value, symsize, type,
1891                                                    binding, visibility, nonvis,
1892                                                    offset_base, only_if_ref);
1893 #else
1894       gold_unreachable();
1895 #endif
1896     }
1897   else if (parameters->target().get_size() == 64)
1898     {
1899 #if defined(HAVE_TARGET_64_LITTLE) || defined(HAVE_TARGET_64_BIG)
1900       return this->do_define_in_output_segment<64>(name, version, defined, os,
1901                                                    value, symsize, type,
1902                                                    binding, visibility, nonvis,
1903                                                    offset_base, only_if_ref);
1904 #else
1905       gold_unreachable();
1906 #endif
1907     }
1908   else
1909     gold_unreachable();
1910 }
1911
1912 // Define a symbol in an Output_segment, sized version.
1913
1914 template<int size>
1915 Sized_symbol<size>*
1916 Symbol_table::do_define_in_output_segment(
1917     const char* name,
1918     const char* version,
1919     Defined defined,
1920     Output_segment* os,
1921     typename elfcpp::Elf_types<size>::Elf_Addr value,
1922     typename elfcpp::Elf_types<size>::Elf_WXword symsize,
1923     elfcpp::STT type,
1924     elfcpp::STB binding,
1925     elfcpp::STV visibility,
1926     unsigned char nonvis,
1927     Symbol::Segment_offset_base offset_base,
1928     bool only_if_ref)
1929 {
1930   Sized_symbol<size>* sym;
1931   Sized_symbol<size>* oldsym;
1932   bool resolve_oldsym;
1933
1934   if (parameters->target().is_big_endian())
1935     {
1936 #if defined(HAVE_TARGET_32_BIG) || defined(HAVE_TARGET_64_BIG)
1937       sym = this->define_special_symbol<size, true>(&name, &version,
1938                                                     only_if_ref, &oldsym,
1939                                                     &resolve_oldsym);
1940 #else
1941       gold_unreachable();
1942 #endif
1943     }
1944   else
1945     {
1946 #if defined(HAVE_TARGET_32_LITTLE) || defined(HAVE_TARGET_64_LITTLE)
1947       sym = this->define_special_symbol<size, false>(&name, &version,
1948                                                      only_if_ref, &oldsym,
1949                                                      &resolve_oldsym);
1950 #else
1951       gold_unreachable();
1952 #endif
1953     }
1954
1955   if (sym == NULL)
1956     return NULL;
1957
1958   sym->init_output_segment(name, version, os, value, symsize, type, binding,
1959                            visibility, nonvis, offset_base);
1960
1961   if (oldsym == NULL)
1962     {
1963       if (binding == elfcpp::STB_LOCAL
1964           || this->version_script_.symbol_is_local(name))
1965         this->force_local(sym);
1966       else if (version != NULL)
1967         sym->set_is_default();
1968       return sym;
1969     }
1970
1971   if (Symbol_table::should_override_with_special(oldsym, defined))
1972     this->override_with_special(oldsym, sym);
1973
1974   if (resolve_oldsym)
1975     return sym;
1976   else
1977     {
1978       delete sym;
1979       return oldsym;
1980     }
1981 }
1982
1983 // Define a special symbol with a constant value.  It is a multiple
1984 // definition error if this symbol is already defined.
1985
1986 Symbol*
1987 Symbol_table::define_as_constant(const char* name,
1988                                  const char* version,
1989                                  Defined defined,
1990                                  uint64_t value,
1991                                  uint64_t symsize,
1992                                  elfcpp::STT type,
1993                                  elfcpp::STB binding,
1994                                  elfcpp::STV visibility,
1995                                  unsigned char nonvis,
1996                                  bool only_if_ref,
1997                                  bool force_override)
1998 {
1999   if (parameters->target().get_size() == 32)
2000     {
2001 #if defined(HAVE_TARGET_32_LITTLE) || defined(HAVE_TARGET_32_BIG)
2002       return this->do_define_as_constant<32>(name, version, defined, value,
2003                                              symsize, type, binding,
2004                                              visibility, nonvis, only_if_ref,
2005                                              force_override);
2006 #else
2007       gold_unreachable();
2008 #endif
2009     }
2010   else if (parameters->target().get_size() == 64)
2011     {
2012 #if defined(HAVE_TARGET_64_LITTLE) || defined(HAVE_TARGET_64_BIG)
2013       return this->do_define_as_constant<64>(name, version, defined, value,
2014                                              symsize, type, binding,
2015                                              visibility, nonvis, only_if_ref,
2016                                              force_override);
2017 #else
2018       gold_unreachable();
2019 #endif
2020     }
2021   else
2022     gold_unreachable();
2023 }
2024
2025 // Define a symbol as a constant, sized version.
2026
2027 template<int size>
2028 Sized_symbol<size>*
2029 Symbol_table::do_define_as_constant(
2030     const char* name,
2031     const char* version,
2032     Defined defined,
2033     typename elfcpp::Elf_types<size>::Elf_Addr value,
2034     typename elfcpp::Elf_types<size>::Elf_WXword symsize,
2035     elfcpp::STT type,
2036     elfcpp::STB binding,
2037     elfcpp::STV visibility,
2038     unsigned char nonvis,
2039     bool only_if_ref,
2040     bool force_override)
2041 {
2042   Sized_symbol<size>* sym;
2043   Sized_symbol<size>* oldsym;
2044   bool resolve_oldsym;
2045
2046   if (parameters->target().is_big_endian())
2047     {
2048 #if defined(HAVE_TARGET_32_BIG) || defined(HAVE_TARGET_64_BIG)
2049       sym = this->define_special_symbol<size, true>(&name, &version,
2050                                                     only_if_ref, &oldsym,
2051                                                     &resolve_oldsym);
2052 #else
2053       gold_unreachable();
2054 #endif
2055     }
2056   else
2057     {
2058 #if defined(HAVE_TARGET_32_LITTLE) || defined(HAVE_TARGET_64_LITTLE)
2059       sym = this->define_special_symbol<size, false>(&name, &version,
2060                                                      only_if_ref, &oldsym,
2061                                                      &resolve_oldsym);
2062 #else
2063       gold_unreachable();
2064 #endif
2065     }
2066
2067   if (sym == NULL)
2068     return NULL;
2069
2070   sym->init_constant(name, version, value, symsize, type, binding, visibility,
2071                      nonvis);
2072
2073   if (oldsym == NULL)
2074     {
2075       // Version symbols are absolute symbols with name == version.
2076       // We don't want to force them to be local.
2077       if ((version == NULL
2078            || name != version
2079            || value != 0)
2080           && (binding == elfcpp::STB_LOCAL
2081               || this->version_script_.symbol_is_local(name)))
2082         this->force_local(sym);
2083       else if (version != NULL
2084                && (name != version || value != 0))
2085         sym->set_is_default();
2086       return sym;
2087     }
2088
2089   if (force_override
2090       || Symbol_table::should_override_with_special(oldsym, defined))
2091     this->override_with_special(oldsym, sym);
2092
2093   if (resolve_oldsym)
2094     return sym;
2095   else
2096     {
2097       delete sym;
2098       return oldsym;
2099     }
2100 }
2101
2102 // Define a set of symbols in output sections.
2103
2104 void
2105 Symbol_table::define_symbols(const Layout* layout, int count,
2106                              const Define_symbol_in_section* p,
2107                              bool only_if_ref)
2108 {
2109   for (int i = 0; i < count; ++i, ++p)
2110     {
2111       Output_section* os = layout->find_output_section(p->output_section);
2112       if (os != NULL)
2113         this->define_in_output_data(p->name, NULL, PREDEFINED, os, p->value,
2114                                     p->size, p->type, p->binding,
2115                                     p->visibility, p->nonvis,
2116                                     p->offset_is_from_end,
2117                                     only_if_ref || p->only_if_ref);
2118       else
2119         this->define_as_constant(p->name, NULL, PREDEFINED, 0, p->size,
2120                                  p->type, p->binding, p->visibility, p->nonvis,
2121                                  only_if_ref || p->only_if_ref,
2122                                  false);
2123     }
2124 }
2125
2126 // Define a set of symbols in output segments.
2127
2128 void
2129 Symbol_table::define_symbols(const Layout* layout, int count,
2130                              const Define_symbol_in_segment* p,
2131                              bool only_if_ref)
2132 {
2133   for (int i = 0; i < count; ++i, ++p)
2134     {
2135       Output_segment* os = layout->find_output_segment(p->segment_type,
2136                                                        p->segment_flags_set,
2137                                                        p->segment_flags_clear);
2138       if (os != NULL)
2139         this->define_in_output_segment(p->name, NULL, PREDEFINED, os, p->value,
2140                                        p->size, p->type, p->binding,
2141                                        p->visibility, p->nonvis,
2142                                        p->offset_base,
2143                                        only_if_ref || p->only_if_ref);
2144       else
2145         this->define_as_constant(p->name, NULL, PREDEFINED, 0, p->size,
2146                                  p->type, p->binding, p->visibility, p->nonvis,
2147                                  only_if_ref || p->only_if_ref,
2148                                  false);
2149     }
2150 }
2151
2152 // Define CSYM using a COPY reloc.  POSD is the Output_data where the
2153 // symbol should be defined--typically a .dyn.bss section.  VALUE is
2154 // the offset within POSD.
2155
2156 template<int size>
2157 void
2158 Symbol_table::define_with_copy_reloc(
2159     Sized_symbol<size>* csym,
2160     Output_data* posd,
2161     typename elfcpp::Elf_types<size>::Elf_Addr value)
2162 {
2163   gold_assert(csym->is_from_dynobj());
2164   gold_assert(!csym->is_copied_from_dynobj());
2165   Object* object = csym->object();
2166   gold_assert(object->is_dynamic());
2167   Dynobj* dynobj = static_cast<Dynobj*>(object);
2168
2169   // Our copied variable has to override any variable in a shared
2170   // library.
2171   elfcpp::STB binding = csym->binding();
2172   if (binding == elfcpp::STB_WEAK)
2173     binding = elfcpp::STB_GLOBAL;
2174
2175   this->define_in_output_data(csym->name(), csym->version(), COPY,
2176                               posd, value, csym->symsize(),
2177                               csym->type(), binding,
2178                               csym->visibility(), csym->nonvis(),
2179                               false, false);
2180
2181   csym->set_is_copied_from_dynobj();
2182   csym->set_needs_dynsym_entry();
2183
2184   this->copied_symbol_dynobjs_[csym] = dynobj;
2185
2186   // We have now defined all aliases, but we have not entered them all
2187   // in the copied_symbol_dynobjs_ map.
2188   if (csym->has_alias())
2189     {
2190       Symbol* sym = csym;
2191       while (true)
2192         {
2193           sym = this->weak_aliases_[sym];
2194           if (sym == csym)
2195             break;
2196           gold_assert(sym->output_data() == posd);
2197
2198           sym->set_is_copied_from_dynobj();
2199           this->copied_symbol_dynobjs_[sym] = dynobj;
2200         }
2201     }
2202 }
2203
2204 // SYM is defined using a COPY reloc.  Return the dynamic object where
2205 // the original definition was found.
2206
2207 Dynobj*
2208 Symbol_table::get_copy_source(const Symbol* sym) const
2209 {
2210   gold_assert(sym->is_copied_from_dynobj());
2211   Copied_symbol_dynobjs::const_iterator p =
2212     this->copied_symbol_dynobjs_.find(sym);
2213   gold_assert(p != this->copied_symbol_dynobjs_.end());
2214   return p->second;
2215 }
2216
2217 // Add any undefined symbols named on the command line.
2218
2219 void
2220 Symbol_table::add_undefined_symbols_from_command_line(Layout* layout)
2221 {
2222   if (parameters->options().any_undefined()
2223       || layout->script_options()->any_unreferenced())
2224     {
2225       if (parameters->target().get_size() == 32)
2226         {
2227 #if defined(HAVE_TARGET_32_LITTLE) || defined(HAVE_TARGET_32_BIG)
2228           this->do_add_undefined_symbols_from_command_line<32>(layout);
2229 #else
2230           gold_unreachable();
2231 #endif
2232         }
2233       else if (parameters->target().get_size() == 64)
2234         {
2235 #if defined(HAVE_TARGET_64_LITTLE) || defined(HAVE_TARGET_64_BIG)
2236           this->do_add_undefined_symbols_from_command_line<64>(layout);
2237 #else
2238           gold_unreachable();
2239 #endif
2240         }
2241       else
2242         gold_unreachable();
2243     }
2244 }
2245
2246 template<int size>
2247 void
2248 Symbol_table::do_add_undefined_symbols_from_command_line(Layout* layout)
2249 {
2250   for (options::String_set::const_iterator p =
2251          parameters->options().undefined_begin();
2252        p != parameters->options().undefined_end();
2253        ++p)
2254     this->add_undefined_symbol_from_command_line<size>(p->c_str());
2255
2256   for (Script_options::referenced_const_iterator p =
2257          layout->script_options()->referenced_begin();
2258        p != layout->script_options()->referenced_end();
2259        ++p)
2260     this->add_undefined_symbol_from_command_line<size>(p->c_str());
2261 }
2262
2263 template<int size>
2264 void
2265 Symbol_table::add_undefined_symbol_from_command_line(const char* name)
2266 {
2267   if (this->lookup(name) != NULL)
2268     return;
2269
2270   const char* version = NULL;
2271
2272   Sized_symbol<size>* sym;
2273   Sized_symbol<size>* oldsym;
2274   bool resolve_oldsym;
2275   if (parameters->target().is_big_endian())
2276     {
2277 #if defined(HAVE_TARGET_32_BIG) || defined(HAVE_TARGET_64_BIG)
2278       sym = this->define_special_symbol<size, true>(&name, &version,
2279                                                     false, &oldsym,
2280                                                     &resolve_oldsym);
2281 #else
2282       gold_unreachable();
2283 #endif
2284     }
2285   else
2286     {
2287 #if defined(HAVE_TARGET_32_LITTLE) || defined(HAVE_TARGET_64_LITTLE)
2288       sym = this->define_special_symbol<size, false>(&name, &version,
2289                                                      false, &oldsym,
2290                                                      &resolve_oldsym);
2291 #else
2292       gold_unreachable();
2293 #endif
2294     }
2295
2296   gold_assert(oldsym == NULL);
2297
2298   sym->init_undefined(name, version, elfcpp::STT_NOTYPE, elfcpp::STB_GLOBAL,
2299                       elfcpp::STV_DEFAULT, 0);
2300   ++this->saw_undefined_;
2301 }
2302
2303 // Set the dynamic symbol indexes.  INDEX is the index of the first
2304 // global dynamic symbol.  Pointers to the symbols are stored into the
2305 // vector SYMS.  The names are added to DYNPOOL.  This returns an
2306 // updated dynamic symbol index.
2307
2308 unsigned int
2309 Symbol_table::set_dynsym_indexes(unsigned int index,
2310                                  std::vector<Symbol*>* syms,
2311                                  Stringpool* dynpool,
2312                                  Versions* versions)
2313 {
2314   for (Symbol_table_type::iterator p = this->table_.begin();
2315        p != this->table_.end();
2316        ++p)
2317     {
2318       Symbol* sym = p->second;
2319
2320       // Note that SYM may already have a dynamic symbol index, since
2321       // some symbols appear more than once in the symbol table, with
2322       // and without a version.
2323
2324       if (!sym->should_add_dynsym_entry(this))
2325         sym->set_dynsym_index(-1U);
2326       else if (!sym->has_dynsym_index())
2327         {
2328           sym->set_dynsym_index(index);
2329           ++index;
2330           syms->push_back(sym);
2331           dynpool->add(sym->name(), false, NULL);
2332
2333           // Record any version information.
2334           if (sym->version() != NULL)
2335             versions->record_version(this, dynpool, sym);
2336
2337           // If the symbol is defined in a dynamic object and is
2338           // referenced in a regular object, then mark the dynamic
2339           // object as needed.  This is used to implement --as-needed.
2340           if (sym->is_from_dynobj() && sym->in_reg())
2341             sym->object()->set_is_needed();
2342         }
2343     }
2344
2345   // Finish up the versions.  In some cases this may add new dynamic
2346   // symbols.
2347   index = versions->finalize(this, index, syms);
2348
2349   return index;
2350 }
2351
2352 // Set the final values for all the symbols.  The index of the first
2353 // global symbol in the output file is *PLOCAL_SYMCOUNT.  Record the
2354 // file offset OFF.  Add their names to POOL.  Return the new file
2355 // offset.  Update *PLOCAL_SYMCOUNT if necessary.
2356
2357 off_t
2358 Symbol_table::finalize(off_t off, off_t dynoff, size_t dyn_global_index,
2359                        size_t dyncount, Stringpool* pool,
2360                        unsigned int* plocal_symcount)
2361 {
2362   off_t ret;
2363
2364   gold_assert(*plocal_symcount != 0);
2365   this->first_global_index_ = *plocal_symcount;
2366
2367   this->dynamic_offset_ = dynoff;
2368   this->first_dynamic_global_index_ = dyn_global_index;
2369   this->dynamic_count_ = dyncount;
2370
2371   if (parameters->target().get_size() == 32)
2372     {
2373 #if defined(HAVE_TARGET_32_BIG) || defined(HAVE_TARGET_32_LITTLE)
2374       ret = this->sized_finalize<32>(off, pool, plocal_symcount);
2375 #else
2376       gold_unreachable();
2377 #endif
2378     }
2379   else if (parameters->target().get_size() == 64)
2380     {
2381 #if defined(HAVE_TARGET_64_BIG) || defined(HAVE_TARGET_64_LITTLE)
2382       ret = this->sized_finalize<64>(off, pool, plocal_symcount);
2383 #else
2384       gold_unreachable();
2385 #endif
2386     }
2387   else
2388     gold_unreachable();
2389
2390   // Now that we have the final symbol table, we can reliably note
2391   // which symbols should get warnings.
2392   this->warnings_.note_warnings(this);
2393
2394   return ret;
2395 }
2396
2397 // SYM is going into the symbol table at *PINDEX.  Add the name to
2398 // POOL, update *PINDEX and *POFF.
2399
2400 template<int size>
2401 void
2402 Symbol_table::add_to_final_symtab(Symbol* sym, Stringpool* pool,
2403                                   unsigned int* pindex, off_t* poff)
2404 {
2405   sym->set_symtab_index(*pindex);
2406   pool->add(sym->name(), false, NULL);
2407   ++*pindex;
2408   *poff += elfcpp::Elf_sizes<size>::sym_size;
2409 }
2410
2411 // Set the final value for all the symbols.  This is called after
2412 // Layout::finalize, so all the output sections have their final
2413 // address.
2414
2415 template<int size>
2416 off_t
2417 Symbol_table::sized_finalize(off_t off, Stringpool* pool,
2418                              unsigned int* plocal_symcount)
2419 {
2420   off = align_address(off, size >> 3);
2421   this->offset_ = off;
2422
2423   unsigned int index = *plocal_symcount;
2424   const unsigned int orig_index = index;
2425
2426   // First do all the symbols which have been forced to be local, as
2427   // they must appear before all global symbols.
2428   for (Forced_locals::iterator p = this->forced_locals_.begin();
2429        p != this->forced_locals_.end();
2430        ++p)
2431     {
2432       Symbol* sym = *p;
2433       gold_assert(sym->is_forced_local());
2434       if (this->sized_finalize_symbol<size>(sym))
2435         {
2436           this->add_to_final_symtab<size>(sym, pool, &index, &off);
2437           ++*plocal_symcount;
2438         }
2439     }
2440
2441   // Now do all the remaining symbols.
2442   for (Symbol_table_type::iterator p = this->table_.begin();
2443        p != this->table_.end();
2444        ++p)
2445     {
2446       Symbol* sym = p->second;
2447       if (this->sized_finalize_symbol<size>(sym))
2448         this->add_to_final_symtab<size>(sym, pool, &index, &off);
2449     }
2450
2451   this->output_count_ = index - orig_index;
2452
2453   return off;
2454 }
2455
2456 // Compute the final value of SYM and store status in location PSTATUS.
2457 // During relaxation, this may be called multiple times for a symbol to
2458 // compute its would-be final value in each relaxation pass.
2459
2460 template<int size>
2461 typename Sized_symbol<size>::Value_type
2462 Symbol_table::compute_final_value(
2463     const Sized_symbol<size>* sym,
2464     Compute_final_value_status* pstatus) const
2465 {
2466   typedef typename Sized_symbol<size>::Value_type Value_type;
2467   Value_type value;
2468
2469   switch (sym->source())
2470     {
2471     case Symbol::FROM_OBJECT:
2472       {
2473         bool is_ordinary;
2474         unsigned int shndx = sym->shndx(&is_ordinary);
2475
2476         if (!is_ordinary
2477             && shndx != elfcpp::SHN_ABS
2478             && !Symbol::is_common_shndx(shndx))
2479           {
2480             *pstatus = CFVS_UNSUPPORTED_SYMBOL_SECTION;
2481             return 0;
2482           }
2483
2484         Object* symobj = sym->object();
2485         if (symobj->is_dynamic())
2486           {
2487             value = 0;
2488             shndx = elfcpp::SHN_UNDEF;
2489           }
2490         else if (symobj->pluginobj() != NULL)
2491           {
2492             value = 0;
2493             shndx = elfcpp::SHN_UNDEF;
2494           }
2495         else if (shndx == elfcpp::SHN_UNDEF)
2496           value = 0;
2497         else if (!is_ordinary
2498                  && (shndx == elfcpp::SHN_ABS
2499                      || Symbol::is_common_shndx(shndx)))
2500           value = sym->value();
2501         else
2502           {
2503             Relobj* relobj = static_cast<Relobj*>(symobj);
2504             Output_section* os = relobj->output_section(shndx);
2505
2506             if (this->is_section_folded(relobj, shndx))
2507               {
2508                 gold_assert(os == NULL);
2509                 // Get the os of the section it is folded onto.
2510                 Section_id folded = this->icf_->get_folded_section(relobj,
2511                                                                    shndx);
2512                 gold_assert(folded.first != NULL);
2513                 Relobj* folded_obj = reinterpret_cast<Relobj*>(folded.first);
2514                 unsigned folded_shndx = folded.second;
2515
2516                 os = folded_obj->output_section(folded_shndx);
2517                 gold_assert(os != NULL);
2518
2519                 // Replace (relobj, shndx) with canonical ICF input section.
2520                 shndx = folded_shndx;
2521                 relobj = folded_obj;
2522               }
2523
2524             uint64_t secoff64 = relobj->output_section_offset(shndx);
2525             if (os == NULL)
2526               {
2527                 bool static_or_reloc = (parameters->doing_static_link() ||
2528                                         parameters->options().relocatable());
2529                 gold_assert(static_or_reloc || sym->dynsym_index() == -1U);
2530
2531                 *pstatus = CFVS_NO_OUTPUT_SECTION;
2532                 return 0;
2533               }
2534
2535             if (secoff64 == -1ULL)
2536               {
2537                 // The section needs special handling (e.g., a merge section).
2538
2539                 value = os->output_address(relobj, shndx, sym->value());
2540               }
2541             else
2542               {
2543                 Value_type secoff =
2544                   convert_types<Value_type, uint64_t>(secoff64);
2545                 if (sym->type() == elfcpp::STT_TLS)
2546                   value = sym->value() + os->tls_offset() + secoff;
2547                 else
2548                   value = sym->value() + os->address() + secoff;
2549               }
2550           }
2551       }
2552       break;
2553
2554     case Symbol::IN_OUTPUT_DATA:
2555       {
2556         Output_data* od = sym->output_data();
2557         value = sym->value();
2558         if (sym->type() != elfcpp::STT_TLS)
2559           value += od->address();
2560         else
2561           {
2562             Output_section* os = od->output_section();
2563             gold_assert(os != NULL);
2564             value += os->tls_offset() + (od->address() - os->address());
2565           }
2566         if (sym->offset_is_from_end())
2567           value += od->data_size();
2568       }
2569       break;
2570
2571     case Symbol::IN_OUTPUT_SEGMENT:
2572       {
2573         Output_segment* os = sym->output_segment();
2574         value = sym->value();
2575         if (sym->type() != elfcpp::STT_TLS)
2576           value += os->vaddr();
2577         switch (sym->offset_base())
2578           {
2579           case Symbol::SEGMENT_START:
2580             break;
2581           case Symbol::SEGMENT_END:
2582             value += os->memsz();
2583             break;
2584           case Symbol::SEGMENT_BSS:
2585             value += os->filesz();
2586             break;
2587           default:
2588             gold_unreachable();
2589           }
2590       }
2591       break;
2592
2593     case Symbol::IS_CONSTANT:
2594       value = sym->value();
2595       break;
2596
2597     case Symbol::IS_UNDEFINED:
2598       value = 0;
2599       break;
2600
2601     default:
2602       gold_unreachable();
2603     }
2604
2605   *pstatus = CFVS_OK;
2606   return value;
2607 }
2608
2609 // Finalize the symbol SYM.  This returns true if the symbol should be
2610 // added to the symbol table, false otherwise.
2611
2612 template<int size>
2613 bool
2614 Symbol_table::sized_finalize_symbol(Symbol* unsized_sym)
2615 {
2616   typedef typename Sized_symbol<size>::Value_type Value_type;
2617
2618   Sized_symbol<size>* sym = static_cast<Sized_symbol<size>*>(unsized_sym);
2619
2620   // The default version of a symbol may appear twice in the symbol
2621   // table.  We only need to finalize it once.
2622   if (sym->has_symtab_index())
2623     return false;
2624
2625   if (!sym->in_reg())
2626     {
2627       gold_assert(!sym->has_symtab_index());
2628       sym->set_symtab_index(-1U);
2629       gold_assert(sym->dynsym_index() == -1U);
2630       return false;
2631     }
2632
2633   // If the symbol is only present on plugin files, the plugin decided we
2634   // don't need it.
2635   if (!sym->in_real_elf())
2636     {
2637       gold_assert(!sym->has_symtab_index());
2638       sym->set_symtab_index(-1U);
2639       return false;
2640     }
2641
2642   // Compute final symbol value.
2643   Compute_final_value_status status;
2644   Value_type value = this->compute_final_value(sym, &status);
2645
2646   switch (status)
2647     {
2648     case CFVS_OK:
2649       break;
2650     case CFVS_UNSUPPORTED_SYMBOL_SECTION:
2651       {
2652         bool is_ordinary;
2653         unsigned int shndx = sym->shndx(&is_ordinary);
2654         gold_error(_("%s: unsupported symbol section 0x%x"),
2655                    sym->demangled_name().c_str(), shndx);
2656       }
2657       break;
2658     case CFVS_NO_OUTPUT_SECTION:
2659       sym->set_symtab_index(-1U);
2660       return false;
2661     default:
2662       gold_unreachable();
2663     }
2664
2665   sym->set_value(value);
2666
2667   if (parameters->options().strip_all()
2668       || !parameters->options().should_retain_symbol(sym->name()))
2669     {
2670       sym->set_symtab_index(-1U);
2671       return false;
2672     }
2673
2674   return true;
2675 }
2676
2677 // Write out the global symbols.
2678
2679 void
2680 Symbol_table::write_globals(const Stringpool* sympool,
2681                             const Stringpool* dynpool,
2682                             Output_symtab_xindex* symtab_xindex,
2683                             Output_symtab_xindex* dynsym_xindex,
2684                             Output_file* of) const
2685 {
2686   switch (parameters->size_and_endianness())
2687     {
2688 #ifdef HAVE_TARGET_32_LITTLE
2689     case Parameters::TARGET_32_LITTLE:
2690       this->sized_write_globals<32, false>(sympool, dynpool, symtab_xindex,
2691                                            dynsym_xindex, of);
2692       break;
2693 #endif
2694 #ifdef HAVE_TARGET_32_BIG
2695     case Parameters::TARGET_32_BIG:
2696       this->sized_write_globals<32, true>(sympool, dynpool, symtab_xindex,
2697                                           dynsym_xindex, of);
2698       break;
2699 #endif
2700 #ifdef HAVE_TARGET_64_LITTLE
2701     case Parameters::TARGET_64_LITTLE:
2702       this->sized_write_globals<64, false>(sympool, dynpool, symtab_xindex,
2703                                            dynsym_xindex, of);
2704       break;
2705 #endif
2706 #ifdef HAVE_TARGET_64_BIG
2707     case Parameters::TARGET_64_BIG:
2708       this->sized_write_globals<64, true>(sympool, dynpool, symtab_xindex,
2709                                           dynsym_xindex, of);
2710       break;
2711 #endif
2712     default:
2713       gold_unreachable();
2714     }
2715 }
2716
2717 // Write out the global symbols.
2718
2719 template<int size, bool big_endian>
2720 void
2721 Symbol_table::sized_write_globals(const Stringpool* sympool,
2722                                   const Stringpool* dynpool,
2723                                   Output_symtab_xindex* symtab_xindex,
2724                                   Output_symtab_xindex* dynsym_xindex,
2725                                   Output_file* of) const
2726 {
2727   const Target& target = parameters->target();
2728
2729   const int sym_size = elfcpp::Elf_sizes<size>::sym_size;
2730
2731   const unsigned int output_count = this->output_count_;
2732   const section_size_type oview_size = output_count * sym_size;
2733   const unsigned int first_global_index = this->first_global_index_;
2734   unsigned char* psyms;
2735   if (this->offset_ == 0 || output_count == 0)
2736     psyms = NULL;
2737   else
2738     psyms = of->get_output_view(this->offset_, oview_size);
2739
2740   const unsigned int dynamic_count = this->dynamic_count_;
2741   const section_size_type dynamic_size = dynamic_count * sym_size;
2742   const unsigned int first_dynamic_global_index =
2743     this->first_dynamic_global_index_;
2744   unsigned char* dynamic_view;
2745   if (this->dynamic_offset_ == 0 || dynamic_count == 0)
2746     dynamic_view = NULL;
2747   else
2748     dynamic_view = of->get_output_view(this->dynamic_offset_, dynamic_size);
2749
2750   for (Symbol_table_type::const_iterator p = this->table_.begin();
2751        p != this->table_.end();
2752        ++p)
2753     {
2754       Sized_symbol<size>* sym = static_cast<Sized_symbol<size>*>(p->second);
2755
2756       // Possibly warn about unresolved symbols in shared libraries.
2757       this->warn_about_undefined_dynobj_symbol(sym);
2758
2759       unsigned int sym_index = sym->symtab_index();
2760       unsigned int dynsym_index;
2761       if (dynamic_view == NULL)
2762         dynsym_index = -1U;
2763       else
2764         dynsym_index = sym->dynsym_index();
2765
2766       if (sym_index == -1U && dynsym_index == -1U)
2767         {
2768           // This symbol is not included in the output file.
2769           continue;
2770         }
2771
2772       unsigned int shndx;
2773       typename elfcpp::Elf_types<size>::Elf_Addr sym_value = sym->value();
2774       typename elfcpp::Elf_types<size>::Elf_Addr dynsym_value = sym_value;
2775       elfcpp::STB binding = sym->binding();
2776       switch (sym->source())
2777         {
2778         case Symbol::FROM_OBJECT:
2779           {
2780             bool is_ordinary;
2781             unsigned int in_shndx = sym->shndx(&is_ordinary);
2782
2783             if (!is_ordinary
2784                 && in_shndx != elfcpp::SHN_ABS
2785                 && !Symbol::is_common_shndx(in_shndx))
2786               {
2787                 gold_error(_("%s: unsupported symbol section 0x%x"),
2788                            sym->demangled_name().c_str(), in_shndx);
2789                 shndx = in_shndx;
2790               }
2791             else
2792               {
2793                 Object* symobj = sym->object();
2794                 if (symobj->is_dynamic())
2795                   {
2796                     if (sym->needs_dynsym_value())
2797                       dynsym_value = target.dynsym_value(sym);
2798                     shndx = elfcpp::SHN_UNDEF;
2799                     if (sym->is_undef_binding_weak())
2800                       binding = elfcpp::STB_WEAK;
2801                     else
2802                       binding = elfcpp::STB_GLOBAL;
2803                   }
2804                 else if (symobj->pluginobj() != NULL)
2805                   shndx = elfcpp::SHN_UNDEF;
2806                 else if (in_shndx == elfcpp::SHN_UNDEF
2807                          || (!is_ordinary
2808                              && (in_shndx == elfcpp::SHN_ABS
2809                                  || Symbol::is_common_shndx(in_shndx))))
2810                   shndx = in_shndx;
2811                 else
2812                   {
2813                     Relobj* relobj = static_cast<Relobj*>(symobj);
2814                     Output_section* os = relobj->output_section(in_shndx);
2815                     if (this->is_section_folded(relobj, in_shndx))
2816                       {
2817                         // This global symbol must be written out even though
2818                         // it is folded.
2819                         // Get the os of the section it is folded onto.
2820                         Section_id folded =
2821                              this->icf_->get_folded_section(relobj, in_shndx);
2822                         gold_assert(folded.first !=NULL);
2823                         Relobj* folded_obj =
2824                           reinterpret_cast<Relobj*>(folded.first);
2825                         os = folded_obj->output_section(folded.second);
2826                         gold_assert(os != NULL);
2827                       }
2828                     gold_assert(os != NULL);
2829                     shndx = os->out_shndx();
2830
2831                     if (shndx >= elfcpp::SHN_LORESERVE)
2832                       {
2833                         if (sym_index != -1U)
2834                           symtab_xindex->add(sym_index, shndx);
2835                         if (dynsym_index != -1U)
2836                           dynsym_xindex->add(dynsym_index, shndx);
2837                         shndx = elfcpp::SHN_XINDEX;
2838                       }
2839
2840                     // In object files symbol values are section
2841                     // relative.
2842                     if (parameters->options().relocatable())
2843                       sym_value -= os->address();
2844                   }
2845               }
2846           }
2847           break;
2848
2849         case Symbol::IN_OUTPUT_DATA:
2850           shndx = sym->output_data()->out_shndx();
2851           if (shndx >= elfcpp::SHN_LORESERVE)
2852             {
2853               if (sym_index != -1U)
2854                 symtab_xindex->add(sym_index, shndx);
2855               if (dynsym_index != -1U)
2856                 dynsym_xindex->add(dynsym_index, shndx);
2857               shndx = elfcpp::SHN_XINDEX;
2858             }
2859           break;
2860
2861         case Symbol::IN_OUTPUT_SEGMENT:
2862           shndx = elfcpp::SHN_ABS;
2863           break;
2864
2865         case Symbol::IS_CONSTANT:
2866           shndx = elfcpp::SHN_ABS;
2867           break;
2868
2869         case Symbol::IS_UNDEFINED:
2870           shndx = elfcpp::SHN_UNDEF;
2871           break;
2872
2873         default:
2874           gold_unreachable();
2875         }
2876
2877       if (sym_index != -1U)
2878         {
2879           sym_index -= first_global_index;
2880           gold_assert(sym_index < output_count);
2881           unsigned char* ps = psyms + (sym_index * sym_size);
2882           this->sized_write_symbol<size, big_endian>(sym, sym_value, shndx,
2883                                                      binding, sympool, ps);
2884         }
2885
2886       if (dynsym_index != -1U)
2887         {
2888           dynsym_index -= first_dynamic_global_index;
2889           gold_assert(dynsym_index < dynamic_count);
2890           unsigned char* pd = dynamic_view + (dynsym_index * sym_size);
2891           this->sized_write_symbol<size, big_endian>(sym, dynsym_value, shndx,
2892                                                      binding, dynpool, pd);
2893         }
2894     }
2895
2896   of->write_output_view(this->offset_, oview_size, psyms);
2897   if (dynamic_view != NULL)
2898     of->write_output_view(this->dynamic_offset_, dynamic_size, dynamic_view);
2899 }
2900
2901 // Write out the symbol SYM, in section SHNDX, to P.  POOL is the
2902 // strtab holding the name.
2903
2904 template<int size, bool big_endian>
2905 void
2906 Symbol_table::sized_write_symbol(
2907     Sized_symbol<size>* sym,
2908     typename elfcpp::Elf_types<size>::Elf_Addr value,
2909     unsigned int shndx,
2910     elfcpp::STB binding,
2911     const Stringpool* pool,
2912     unsigned char* p) const
2913 {
2914   elfcpp::Sym_write<size, big_endian> osym(p);
2915   osym.put_st_name(pool->get_offset(sym->name()));
2916   osym.put_st_value(value);
2917   // Use a symbol size of zero for undefined symbols from shared libraries.
2918   if (shndx == elfcpp::SHN_UNDEF && sym->is_from_dynobj())
2919     osym.put_st_size(0);
2920   else
2921     osym.put_st_size(sym->symsize());
2922   elfcpp::STT type = sym->type();
2923   // Turn IFUNC symbols from shared libraries into normal FUNC symbols.
2924   if (type == elfcpp::STT_GNU_IFUNC
2925       && sym->is_from_dynobj())
2926     type = elfcpp::STT_FUNC;
2927   // A version script may have overridden the default binding.
2928   if (sym->is_forced_local())
2929     osym.put_st_info(elfcpp::elf_st_info(elfcpp::STB_LOCAL, type));
2930   else
2931     osym.put_st_info(elfcpp::elf_st_info(binding, type));
2932   osym.put_st_other(elfcpp::elf_st_other(sym->visibility(), sym->nonvis()));
2933   osym.put_st_shndx(shndx);
2934 }
2935
2936 // Check for unresolved symbols in shared libraries.  This is
2937 // controlled by the --allow-shlib-undefined option.
2938
2939 // We only warn about libraries for which we have seen all the
2940 // DT_NEEDED entries.  We don't try to track down DT_NEEDED entries
2941 // which were not seen in this link.  If we didn't see a DT_NEEDED
2942 // entry, we aren't going to be able to reliably report whether the
2943 // symbol is undefined.
2944
2945 // We also don't warn about libraries found in a system library
2946 // directory (e.g., /lib or /usr/lib); we assume that those libraries
2947 // are OK.  This heuristic avoids problems on GNU/Linux, in which -ldl
2948 // can have undefined references satisfied by ld-linux.so.
2949
2950 inline void
2951 Symbol_table::warn_about_undefined_dynobj_symbol(Symbol* sym) const
2952 {
2953   bool dummy;
2954   if (sym->source() == Symbol::FROM_OBJECT
2955       && sym->object()->is_dynamic()
2956       && sym->shndx(&dummy) == elfcpp::SHN_UNDEF
2957       && sym->binding() != elfcpp::STB_WEAK
2958       && !parameters->options().allow_shlib_undefined()
2959       && !parameters->target().is_defined_by_abi(sym)
2960       && !sym->object()->is_in_system_directory())
2961     {
2962       // A very ugly cast.
2963       Dynobj* dynobj = static_cast<Dynobj*>(sym->object());
2964       if (!dynobj->has_unknown_needed_entries())
2965         gold_undefined_symbol(sym);
2966     }
2967 }
2968
2969 // Write out a section symbol.  Return the update offset.
2970
2971 void
2972 Symbol_table::write_section_symbol(const Output_section* os,
2973                                    Output_symtab_xindex* symtab_xindex,
2974                                    Output_file* of,
2975                                    off_t offset) const
2976 {
2977   switch (parameters->size_and_endianness())
2978     {
2979 #ifdef HAVE_TARGET_32_LITTLE
2980     case Parameters::TARGET_32_LITTLE:
2981       this->sized_write_section_symbol<32, false>(os, symtab_xindex, of,
2982                                                   offset);
2983       break;
2984 #endif
2985 #ifdef HAVE_TARGET_32_BIG
2986     case Parameters::TARGET_32_BIG:
2987       this->sized_write_section_symbol<32, true>(os, symtab_xindex, of,
2988                                                  offset);
2989       break;
2990 #endif
2991 #ifdef HAVE_TARGET_64_LITTLE
2992     case Parameters::TARGET_64_LITTLE:
2993       this->sized_write_section_symbol<64, false>(os, symtab_xindex, of,
2994                                                   offset);
2995       break;
2996 #endif
2997 #ifdef HAVE_TARGET_64_BIG
2998     case Parameters::TARGET_64_BIG:
2999       this->sized_write_section_symbol<64, true>(os, symtab_xindex, of,
3000                                                  offset);
3001       break;
3002 #endif
3003     default:
3004       gold_unreachable();
3005     }
3006 }
3007
3008 // Write out a section symbol, specialized for size and endianness.
3009
3010 template<int size, bool big_endian>
3011 void
3012 Symbol_table::sized_write_section_symbol(const Output_section* os,
3013                                          Output_symtab_xindex* symtab_xindex,
3014                                          Output_file* of,
3015                                          off_t offset) const
3016 {
3017   const int sym_size = elfcpp::Elf_sizes<size>::sym_size;
3018
3019   unsigned char* pov = of->get_output_view(offset, sym_size);
3020
3021   elfcpp::Sym_write<size, big_endian> osym(pov);
3022   osym.put_st_name(0);
3023   if (parameters->options().relocatable())
3024     osym.put_st_value(0);
3025   else
3026     osym.put_st_value(os->address());
3027   osym.put_st_size(0);
3028   osym.put_st_info(elfcpp::elf_st_info(elfcpp::STB_LOCAL,
3029                                        elfcpp::STT_SECTION));
3030   osym.put_st_other(elfcpp::elf_st_other(elfcpp::STV_DEFAULT, 0));
3031
3032   unsigned int shndx = os->out_shndx();
3033   if (shndx >= elfcpp::SHN_LORESERVE)
3034     {
3035       symtab_xindex->add(os->symtab_index(), shndx);
3036       shndx = elfcpp::SHN_XINDEX;
3037     }
3038   osym.put_st_shndx(shndx);
3039
3040   of->write_output_view(offset, sym_size, pov);
3041 }
3042
3043 // Print statistical information to stderr.  This is used for --stats.
3044
3045 void
3046 Symbol_table::print_stats() const
3047 {
3048 #if defined(HAVE_TR1_UNORDERED_MAP) || defined(HAVE_EXT_HASH_MAP)
3049   fprintf(stderr, _("%s: symbol table entries: %zu; buckets: %zu\n"),
3050           program_name, this->table_.size(), this->table_.bucket_count());
3051 #else
3052   fprintf(stderr, _("%s: symbol table entries: %zu\n"),
3053           program_name, this->table_.size());
3054 #endif
3055   this->namepool_.print_stats("symbol table stringpool");
3056 }
3057
3058 // We check for ODR violations by looking for symbols with the same
3059 // name for which the debugging information reports that they were
3060 // defined in disjoint source locations.  When comparing the source
3061 // location, we consider instances with the same base filename to be
3062 // the same.  This is because different object files/shared libraries
3063 // can include the same header file using different paths, and
3064 // different optimization settings can make the line number appear to
3065 // be a couple lines off, and we don't want to report an ODR violation
3066 // in those cases.
3067
3068 // This struct is used to compare line information, as returned by
3069 // Dwarf_line_info::one_addr2line.  It implements a < comparison
3070 // operator used with std::sort.
3071
3072 struct Odr_violation_compare
3073 {
3074   bool
3075   operator()(const std::string& s1, const std::string& s2) const
3076   {
3077     // Inputs should be of the form "dirname/filename:linenum" where
3078     // "dirname/" is optional.  We want to compare just the filename:linenum.
3079
3080     // Find the last '/' in each string.
3081     std::string::size_type s1begin = s1.rfind('/');
3082     std::string::size_type s2begin = s2.rfind('/');
3083     // If there was no '/' in a string, start at the beginning.
3084     if (s1begin == std::string::npos)
3085       s1begin = 0;
3086     if (s2begin == std::string::npos)
3087       s2begin = 0;
3088     return s1.compare(s1begin, std::string::npos,
3089                       s2, s2begin, std::string::npos) < 0;
3090   }
3091 };
3092
3093 // Returns all of the lines attached to LOC, not just the one the
3094 // instruction actually came from.
3095 std::vector<std::string>
3096 Symbol_table::linenos_from_loc(const Task* task,
3097                                const Symbol_location& loc)
3098 {
3099   // We need to lock the object in order to read it.  This
3100   // means that we have to run in a singleton Task.  If we
3101   // want to run this in a general Task for better
3102   // performance, we will need one Task for object, plus
3103   // appropriate locking to ensure that we don't conflict with
3104   // other uses of the object.  Also note, one_addr2line is not
3105   // currently thread-safe.
3106   Task_lock_obj<Object> tl(task, loc.object);
3107
3108   std::vector<std::string> result;
3109   // 16 is the size of the object-cache that one_addr2line should use.
3110   std::string canonical_result = Dwarf_line_info::one_addr2line(
3111       loc.object, loc.shndx, loc.offset, 16, &result);
3112   if (!canonical_result.empty())
3113     result.push_back(canonical_result);
3114   return result;
3115 }
3116
3117 // OutputIterator that records if it was ever assigned to.  This
3118 // allows it to be used with std::set_intersection() to check for
3119 // intersection rather than computing the intersection.
3120 struct Check_intersection
3121 {
3122   Check_intersection()
3123     : value_(false)
3124   {}
3125
3126   bool had_intersection() const
3127   { return this->value_; }
3128
3129   Check_intersection& operator++()
3130   { return *this; }
3131
3132   Check_intersection& operator*()
3133   { return *this; }
3134
3135   template<typename T>
3136   Check_intersection& operator=(const T&)
3137   {
3138     this->value_ = true;
3139     return *this;
3140   }
3141
3142  private:
3143   bool value_;
3144 };
3145
3146 // Check candidate_odr_violations_ to find symbols with the same name
3147 // but apparently different definitions (different source-file/line-no
3148 // for each line assigned to the first instruction).
3149
3150 void
3151 Symbol_table::detect_odr_violations(const Task* task,
3152                                     const char* output_file_name) const
3153 {
3154   for (Odr_map::const_iterator it = candidate_odr_violations_.begin();
3155        it != candidate_odr_violations_.end();
3156        ++it)
3157     {
3158       const char* const symbol_name = it->first;
3159
3160       std::string first_object_name;
3161       std::vector<std::string> first_object_linenos;
3162
3163       Unordered_set<Symbol_location, Symbol_location_hash>::const_iterator
3164           locs = it->second.begin();
3165       const Unordered_set<Symbol_location, Symbol_location_hash>::const_iterator
3166           locs_end = it->second.end();
3167       for (; locs != locs_end && first_object_linenos.empty(); ++locs)
3168         {
3169           // Save the line numbers from the first definition to
3170           // compare to the other definitions.  Ideally, we'd compare
3171           // every definition to every other, but we don't want to
3172           // take O(N^2) time to do this.  This shortcut may cause
3173           // false negatives that appear or disappear depending on the
3174           // link order, but it won't cause false positives.
3175           first_object_name = locs->object->name();
3176           first_object_linenos = this->linenos_from_loc(task, *locs);
3177         }
3178
3179       // Sort by Odr_violation_compare to make std::set_intersection work.
3180       std::sort(first_object_linenos.begin(), first_object_linenos.end(),
3181                 Odr_violation_compare());
3182
3183       for (; locs != locs_end; ++locs)
3184         {
3185           std::vector<std::string> linenos =
3186               this->linenos_from_loc(task, *locs);
3187           // linenos will be empty if we couldn't parse the debug info.
3188           if (linenos.empty())
3189             continue;
3190           // Sort by Odr_violation_compare to make std::set_intersection work.
3191           std::sort(linenos.begin(), linenos.end(), Odr_violation_compare());
3192
3193           Check_intersection intersection_result =
3194               std::set_intersection(first_object_linenos.begin(),
3195                                     first_object_linenos.end(),
3196                                     linenos.begin(),
3197                                     linenos.end(),
3198                                     Check_intersection(),
3199                                     Odr_violation_compare());
3200           if (!intersection_result.had_intersection())
3201             {
3202               gold_warning(_("while linking %s: symbol '%s' defined in "
3203                              "multiple places (possible ODR violation):"),
3204                            output_file_name, demangle(symbol_name).c_str());
3205               // This only prints one location from each definition,
3206               // which may not be the location we expect to intersect
3207               // with another definition.  We could print the whole
3208               // set of locations, but that seems too verbose.
3209               gold_assert(!first_object_linenos.empty());
3210               gold_assert(!linenos.empty());
3211               fprintf(stderr, _("  %s from %s\n"),
3212                       first_object_linenos[0].c_str(),
3213                       first_object_name.c_str());
3214               fprintf(stderr, _("  %s from %s\n"),
3215                       linenos[0].c_str(),
3216                       locs->object->name().c_str());
3217               // Only print one broken pair, to avoid needing to
3218               // compare against a list of the disjoint definition
3219               // locations we've found so far.  (If we kept comparing
3220               // against just the first one, we'd get a lot of
3221               // redundant complaints about the second definition
3222               // location.)
3223               break;
3224             }
3225         }
3226     }
3227   // We only call one_addr2line() in this function, so we can clear its cache.
3228   Dwarf_line_info::clear_addr2line_cache();
3229 }
3230
3231 // Warnings functions.
3232
3233 // Add a new warning.
3234
3235 void
3236 Warnings::add_warning(Symbol_table* symtab, const char* name, Object* obj,
3237                       const std::string& warning)
3238 {
3239   name = symtab->canonicalize_name(name);
3240   this->warnings_[name].set(obj, warning);
3241 }
3242
3243 // Look through the warnings and mark the symbols for which we should
3244 // warn.  This is called during Layout::finalize when we know the
3245 // sources for all the symbols.
3246
3247 void
3248 Warnings::note_warnings(Symbol_table* symtab)
3249 {
3250   for (Warning_table::iterator p = this->warnings_.begin();
3251        p != this->warnings_.end();
3252        ++p)
3253     {
3254       Symbol* sym = symtab->lookup(p->first, NULL);
3255       if (sym != NULL
3256           && sym->source() == Symbol::FROM_OBJECT
3257           && sym->object() == p->second.object)
3258         sym->set_has_warning();
3259     }
3260 }
3261
3262 // Issue a warning.  This is called when we see a relocation against a
3263 // symbol for which has a warning.
3264
3265 template<int size, bool big_endian>
3266 void
3267 Warnings::issue_warning(const Symbol* sym,
3268                         const Relocate_info<size, big_endian>* relinfo,
3269                         size_t relnum, off_t reloffset) const
3270 {
3271   gold_assert(sym->has_warning());
3272   Warning_table::const_iterator p = this->warnings_.find(sym->name());
3273   gold_assert(p != this->warnings_.end());
3274   gold_warning_at_location(relinfo, relnum, reloffset,
3275                            "%s", p->second.text.c_str());
3276 }
3277
3278 // Instantiate the templates we need.  We could use the configure
3279 // script to restrict this to only the ones needed for implemented
3280 // targets.
3281
3282 #if defined(HAVE_TARGET_32_LITTLE) || defined(HAVE_TARGET_32_BIG)
3283 template
3284 void
3285 Sized_symbol<32>::allocate_common(Output_data*, Value_type);
3286 #endif
3287
3288 #if defined(HAVE_TARGET_64_LITTLE) || defined(HAVE_TARGET_64_BIG)
3289 template
3290 void
3291 Sized_symbol<64>::allocate_common(Output_data*, Value_type);
3292 #endif
3293
3294 #ifdef HAVE_TARGET_32_LITTLE
3295 template
3296 void
3297 Symbol_table::add_from_relobj<32, false>(
3298     Sized_relobj<32, false>* relobj,
3299     const unsigned char* syms,
3300     size_t count,
3301     size_t symndx_offset,
3302     const char* sym_names,
3303     size_t sym_name_size,
3304     Sized_relobj<32, false>::Symbols* sympointers,
3305     size_t* defined);
3306 #endif
3307
3308 #ifdef HAVE_TARGET_32_BIG
3309 template
3310 void
3311 Symbol_table::add_from_relobj<32, true>(
3312     Sized_relobj<32, true>* relobj,
3313     const unsigned char* syms,
3314     size_t count,
3315     size_t symndx_offset,
3316     const char* sym_names,
3317     size_t sym_name_size,
3318     Sized_relobj<32, true>::Symbols* sympointers,
3319     size_t* defined);
3320 #endif
3321
3322 #ifdef HAVE_TARGET_64_LITTLE
3323 template
3324 void
3325 Symbol_table::add_from_relobj<64, false>(
3326     Sized_relobj<64, false>* relobj,
3327     const unsigned char* syms,
3328     size_t count,
3329     size_t symndx_offset,
3330     const char* sym_names,
3331     size_t sym_name_size,
3332     Sized_relobj<64, false>::Symbols* sympointers,
3333     size_t* defined);
3334 #endif
3335
3336 #ifdef HAVE_TARGET_64_BIG
3337 template
3338 void
3339 Symbol_table::add_from_relobj<64, true>(
3340     Sized_relobj<64, true>* relobj,
3341     const unsigned char* syms,
3342     size_t count,
3343     size_t symndx_offset,
3344     const char* sym_names,
3345     size_t sym_name_size,
3346     Sized_relobj<64, true>::Symbols* sympointers,
3347     size_t* defined);
3348 #endif
3349
3350 #ifdef HAVE_TARGET_32_LITTLE
3351 template
3352 Symbol*
3353 Symbol_table::add_from_pluginobj<32, false>(
3354     Sized_pluginobj<32, false>* obj,
3355     const char* name,
3356     const char* ver,
3357     elfcpp::Sym<32, false>* sym);
3358 #endif
3359
3360 #ifdef HAVE_TARGET_32_BIG
3361 template
3362 Symbol*
3363 Symbol_table::add_from_pluginobj<32, true>(
3364     Sized_pluginobj<32, true>* obj,
3365     const char* name,
3366     const char* ver,
3367     elfcpp::Sym<32, true>* sym);
3368 #endif
3369
3370 #ifdef HAVE_TARGET_64_LITTLE
3371 template
3372 Symbol*
3373 Symbol_table::add_from_pluginobj<64, false>(
3374     Sized_pluginobj<64, false>* obj,
3375     const char* name,
3376     const char* ver,
3377     elfcpp::Sym<64, false>* sym);
3378 #endif
3379
3380 #ifdef HAVE_TARGET_64_BIG
3381 template
3382 Symbol*
3383 Symbol_table::add_from_pluginobj<64, true>(
3384     Sized_pluginobj<64, true>* obj,
3385     const char* name,
3386     const char* ver,
3387     elfcpp::Sym<64, true>* sym);
3388 #endif
3389
3390 #ifdef HAVE_TARGET_32_LITTLE
3391 template
3392 void
3393 Symbol_table::add_from_dynobj<32, false>(
3394     Sized_dynobj<32, false>* dynobj,
3395     const unsigned char* syms,
3396     size_t count,
3397     const char* sym_names,
3398     size_t sym_name_size,
3399     const unsigned char* versym,
3400     size_t versym_size,
3401     const std::vector<const char*>* version_map,
3402     Sized_relobj<32, false>::Symbols* sympointers,
3403     size_t* defined);
3404 #endif
3405
3406 #ifdef HAVE_TARGET_32_BIG
3407 template
3408 void
3409 Symbol_table::add_from_dynobj<32, true>(
3410     Sized_dynobj<32, true>* dynobj,
3411     const unsigned char* syms,
3412     size_t count,
3413     const char* sym_names,
3414     size_t sym_name_size,
3415     const unsigned char* versym,
3416     size_t versym_size,
3417     const std::vector<const char*>* version_map,
3418     Sized_relobj<32, true>::Symbols* sympointers,
3419     size_t* defined);
3420 #endif
3421
3422 #ifdef HAVE_TARGET_64_LITTLE
3423 template
3424 void
3425 Symbol_table::add_from_dynobj<64, false>(
3426     Sized_dynobj<64, false>* dynobj,
3427     const unsigned char* syms,
3428     size_t count,
3429     const char* sym_names,
3430     size_t sym_name_size,
3431     const unsigned char* versym,
3432     size_t versym_size,
3433     const std::vector<const char*>* version_map,
3434     Sized_relobj<64, false>::Symbols* sympointers,
3435     size_t* defined);
3436 #endif
3437
3438 #ifdef HAVE_TARGET_64_BIG
3439 template
3440 void
3441 Symbol_table::add_from_dynobj<64, true>(
3442     Sized_dynobj<64, true>* dynobj,
3443     const unsigned char* syms,
3444     size_t count,
3445     const char* sym_names,
3446     size_t sym_name_size,
3447     const unsigned char* versym,
3448     size_t versym_size,
3449     const std::vector<const char*>* version_map,
3450     Sized_relobj<64, true>::Symbols* sympointers,
3451     size_t* defined);
3452 #endif
3453
3454 #ifdef HAVE_TARGET_32_LITTLE
3455 template
3456 Symbol*
3457 Symbol_table::add_from_incrobj(
3458     Object* obj,
3459     const char* name,
3460     const char* ver,
3461     elfcpp::Sym<32, false>* sym);
3462 #endif
3463
3464 #ifdef HAVE_TARGET_32_BIG
3465 template
3466 Symbol*
3467 Symbol_table::add_from_incrobj(
3468     Object* obj,
3469     const char* name,
3470     const char* ver,
3471     elfcpp::Sym<32, true>* sym);
3472 #endif
3473
3474 #ifdef HAVE_TARGET_64_LITTLE
3475 template
3476 Symbol*
3477 Symbol_table::add_from_incrobj(
3478     Object* obj,
3479     const char* name,
3480     const char* ver,
3481     elfcpp::Sym<64, false>* sym);
3482 #endif
3483
3484 #ifdef HAVE_TARGET_64_BIG
3485 template
3486 Symbol*
3487 Symbol_table::add_from_incrobj(
3488     Object* obj,
3489     const char* name,
3490     const char* ver,
3491     elfcpp::Sym<64, true>* sym);
3492 #endif
3493
3494 #if defined(HAVE_TARGET_32_LITTLE) || defined(HAVE_TARGET_32_BIG)
3495 template
3496 void
3497 Symbol_table::define_with_copy_reloc<32>(
3498     Sized_symbol<32>* sym,
3499     Output_data* posd,
3500     elfcpp::Elf_types<32>::Elf_Addr value);
3501 #endif
3502
3503 #if defined(HAVE_TARGET_64_LITTLE) || defined(HAVE_TARGET_64_BIG)
3504 template
3505 void
3506 Symbol_table::define_with_copy_reloc<64>(
3507     Sized_symbol<64>* sym,
3508     Output_data* posd,
3509     elfcpp::Elf_types<64>::Elf_Addr value);
3510 #endif
3511
3512 #ifdef HAVE_TARGET_32_LITTLE
3513 template
3514 void
3515 Warnings::issue_warning<32, false>(const Symbol* sym,
3516                                    const Relocate_info<32, false>* relinfo,
3517                                    size_t relnum, off_t reloffset) const;
3518 #endif
3519
3520 #ifdef HAVE_TARGET_32_BIG
3521 template
3522 void
3523 Warnings::issue_warning<32, true>(const Symbol* sym,
3524                                   const Relocate_info<32, true>* relinfo,
3525                                   size_t relnum, off_t reloffset) const;
3526 #endif
3527
3528 #ifdef HAVE_TARGET_64_LITTLE
3529 template
3530 void
3531 Warnings::issue_warning<64, false>(const Symbol* sym,
3532                                    const Relocate_info<64, false>* relinfo,
3533                                    size_t relnum, off_t reloffset) const;
3534 #endif
3535
3536 #ifdef HAVE_TARGET_64_BIG
3537 template
3538 void
3539 Warnings::issue_warning<64, true>(const Symbol* sym,
3540                                   const Relocate_info<64, true>* relinfo,
3541                                   size_t relnum, off_t reloffset) const;
3542 #endif
3543
3544 } // End namespace gold.