1 // symtab.cc -- the gold symbol table
3 // Copyright 2006, 2007, 2008, 2009, 2010 Free Software Foundation, Inc.
4 // Written by Ian Lance Taylor <iant@google.com>.
6 // This file is part of gold.
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.
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.
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.
35 #include "dwarf_reader.h"
39 #include "workqueue.h"
41 #include "demangle.h" // needed for --dynamic-list-cpp-new
49 // Initialize fields in Symbol. This initializes everything except u_
53 Symbol::init_fields(const char* name, const char* version,
54 elfcpp::STT type, elfcpp::STB binding,
55 elfcpp::STV visibility, unsigned char nonvis)
58 this->version_ = version;
59 this->symtab_index_ = 0;
60 this->dynsym_index_ = 0;
61 this->got_offsets_.init();
62 this->plt_offset_ = -1U;
64 this->binding_ = binding;
65 this->visibility_ = visibility;
66 this->nonvis_ = nonvis;
67 this->is_def_ = false;
68 this->is_forwarder_ = false;
69 this->has_alias_ = false;
70 this->needs_dynsym_entry_ = false;
71 this->in_reg_ = false;
72 this->in_dyn_ = false;
73 this->has_warning_ = false;
74 this->is_copied_from_dynobj_ = false;
75 this->is_forced_local_ = false;
76 this->is_ordinary_shndx_ = false;
77 this->in_real_elf_ = false;
78 this->is_defined_in_discarded_section_ = false;
79 this->undef_binding_set_ = false;
80 this->undef_binding_weak_ = false;
83 // Return the demangled version of the symbol's name, but only
84 // if the --demangle flag was set.
87 demangle(const char* name)
89 if (!parameters->options().do_demangle())
92 // cplus_demangle allocates memory for the result it returns,
93 // and returns NULL if the name is already demangled.
94 char* demangled_name = cplus_demangle(name, DMGL_ANSI | DMGL_PARAMS);
95 if (demangled_name == NULL)
98 std::string retval(demangled_name);
104 Symbol::demangled_name() const
106 return demangle(this->name());
109 // Initialize the fields in the base class Symbol for SYM in OBJECT.
111 template<int size, bool big_endian>
113 Symbol::init_base_object(const char* name, const char* version, Object* object,
114 const elfcpp::Sym<size, big_endian>& sym,
115 unsigned int st_shndx, bool is_ordinary)
117 this->init_fields(name, version, sym.get_st_type(), sym.get_st_bind(),
118 sym.get_st_visibility(), sym.get_st_nonvis());
119 this->u_.from_object.object = object;
120 this->u_.from_object.shndx = st_shndx;
121 this->is_ordinary_shndx_ = is_ordinary;
122 this->source_ = FROM_OBJECT;
123 this->in_reg_ = !object->is_dynamic();
124 this->in_dyn_ = object->is_dynamic();
125 this->in_real_elf_ = object->pluginobj() == NULL;
128 // Initialize the fields in the base class Symbol for a symbol defined
129 // in an Output_data.
132 Symbol::init_base_output_data(const char* name, const char* version,
133 Output_data* od, elfcpp::STT type,
134 elfcpp::STB binding, elfcpp::STV visibility,
135 unsigned char nonvis, bool offset_is_from_end)
137 this->init_fields(name, version, type, binding, visibility, nonvis);
138 this->u_.in_output_data.output_data = od;
139 this->u_.in_output_data.offset_is_from_end = offset_is_from_end;
140 this->source_ = IN_OUTPUT_DATA;
141 this->in_reg_ = true;
142 this->in_real_elf_ = true;
145 // Initialize the fields in the base class Symbol for a symbol defined
146 // in an Output_segment.
149 Symbol::init_base_output_segment(const char* name, const char* version,
150 Output_segment* os, elfcpp::STT type,
151 elfcpp::STB binding, elfcpp::STV visibility,
152 unsigned char nonvis,
153 Segment_offset_base offset_base)
155 this->init_fields(name, version, type, binding, visibility, nonvis);
156 this->u_.in_output_segment.output_segment = os;
157 this->u_.in_output_segment.offset_base = offset_base;
158 this->source_ = IN_OUTPUT_SEGMENT;
159 this->in_reg_ = true;
160 this->in_real_elf_ = true;
163 // Initialize the fields in the base class Symbol for a symbol defined
167 Symbol::init_base_constant(const char* name, const char* version,
168 elfcpp::STT type, elfcpp::STB binding,
169 elfcpp::STV visibility, unsigned char nonvis)
171 this->init_fields(name, version, type, binding, visibility, nonvis);
172 this->source_ = IS_CONSTANT;
173 this->in_reg_ = true;
174 this->in_real_elf_ = true;
177 // Initialize the fields in the base class Symbol for an undefined
181 Symbol::init_base_undefined(const char* name, const char* version,
182 elfcpp::STT type, elfcpp::STB binding,
183 elfcpp::STV visibility, unsigned char nonvis)
185 this->init_fields(name, version, type, binding, visibility, nonvis);
186 this->dynsym_index_ = -1U;
187 this->source_ = IS_UNDEFINED;
188 this->in_reg_ = true;
189 this->in_real_elf_ = true;
192 // Allocate a common symbol in the base.
195 Symbol::allocate_base_common(Output_data* od)
197 gold_assert(this->is_common());
198 this->source_ = IN_OUTPUT_DATA;
199 this->u_.in_output_data.output_data = od;
200 this->u_.in_output_data.offset_is_from_end = false;
203 // Initialize the fields in Sized_symbol for SYM in OBJECT.
206 template<bool big_endian>
208 Sized_symbol<size>::init_object(const char* name, const char* version,
210 const elfcpp::Sym<size, big_endian>& sym,
211 unsigned int st_shndx, bool is_ordinary)
213 this->init_base_object(name, version, object, sym, st_shndx, is_ordinary);
214 this->value_ = sym.get_st_value();
215 this->symsize_ = sym.get_st_size();
218 // Initialize the fields in Sized_symbol for a symbol defined in an
223 Sized_symbol<size>::init_output_data(const char* name, const char* version,
224 Output_data* od, Value_type value,
225 Size_type symsize, elfcpp::STT type,
227 elfcpp::STV visibility,
228 unsigned char nonvis,
229 bool offset_is_from_end)
231 this->init_base_output_data(name, version, od, type, binding, visibility,
232 nonvis, offset_is_from_end);
233 this->value_ = value;
234 this->symsize_ = symsize;
237 // Initialize the fields in Sized_symbol for a symbol defined in an
242 Sized_symbol<size>::init_output_segment(const char* name, const char* version,
243 Output_segment* os, Value_type value,
244 Size_type symsize, elfcpp::STT type,
246 elfcpp::STV visibility,
247 unsigned char nonvis,
248 Segment_offset_base offset_base)
250 this->init_base_output_segment(name, version, os, type, binding, visibility,
251 nonvis, offset_base);
252 this->value_ = value;
253 this->symsize_ = symsize;
256 // Initialize the fields in Sized_symbol for a symbol defined as a
261 Sized_symbol<size>::init_constant(const char* name, const char* version,
262 Value_type value, Size_type symsize,
263 elfcpp::STT type, elfcpp::STB binding,
264 elfcpp::STV visibility, unsigned char nonvis)
266 this->init_base_constant(name, version, type, binding, visibility, nonvis);
267 this->value_ = value;
268 this->symsize_ = symsize;
271 // Initialize the fields in Sized_symbol for an undefined symbol.
275 Sized_symbol<size>::init_undefined(const char* name, const char* version,
276 elfcpp::STT type, elfcpp::STB binding,
277 elfcpp::STV visibility, unsigned char nonvis)
279 this->init_base_undefined(name, version, type, binding, visibility, nonvis);
284 // Return true if SHNDX represents a common symbol.
287 Symbol::is_common_shndx(unsigned int shndx)
289 return (shndx == elfcpp::SHN_COMMON
290 || shndx == parameters->target().small_common_shndx()
291 || shndx == parameters->target().large_common_shndx());
294 // Allocate a common symbol.
298 Sized_symbol<size>::allocate_common(Output_data* od, Value_type value)
300 this->allocate_base_common(od);
301 this->value_ = value;
304 // The ""'s around str ensure str is a string literal, so sizeof works.
305 #define strprefix(var, str) (strncmp(var, str, sizeof("" str "") - 1) == 0)
307 // Return true if this symbol should be added to the dynamic symbol
311 Symbol::should_add_dynsym_entry(Symbol_table* symtab) const
313 // If the symbol is used by a dynamic relocation, we need to add it.
314 if (this->needs_dynsym_entry())
317 // If this symbol's section is not added, the symbol need not be added.
318 // The section may have been GCed. Note that export_dynamic is being
319 // overridden here. This should not be done for shared objects.
320 if (parameters->options().gc_sections()
321 && !parameters->options().shared()
322 && this->source() == Symbol::FROM_OBJECT
323 && !this->object()->is_dynamic())
325 Relobj* relobj = static_cast<Relobj*>(this->object());
327 unsigned int shndx = this->shndx(&is_ordinary);
328 if (is_ordinary && shndx != elfcpp::SHN_UNDEF
329 && !relobj->is_section_included(shndx)
330 && !symtab->is_section_folded(relobj, shndx))
334 // If the symbol was forced local in a version script, do not add it.
335 if (this->is_forced_local())
338 // If the symbol was forced dynamic in a --dynamic-list file, add it.
339 if (parameters->options().in_dynamic_list(this->name()))
342 // If dynamic-list-data was specified, add any STT_OBJECT.
343 if (parameters->options().dynamic_list_data()
344 && !this->is_from_dynobj()
345 && this->type() == elfcpp::STT_OBJECT)
348 // If --dynamic-list-cpp-new was specified, add any new/delete symbol.
349 // If --dynamic-list-cpp-typeinfo was specified, add any typeinfo symbols.
350 if ((parameters->options().dynamic_list_cpp_new()
351 || parameters->options().dynamic_list_cpp_typeinfo())
352 && !this->is_from_dynobj())
354 // TODO(csilvers): We could probably figure out if we're an operator
355 // new/delete or typeinfo without the need to demangle.
356 char* demangled_name = cplus_demangle(this->name(),
357 DMGL_ANSI | DMGL_PARAMS);
358 if (demangled_name == NULL)
360 // Not a C++ symbol, so it can't satisfy these flags
362 else if (parameters->options().dynamic_list_cpp_new()
363 && (strprefix(demangled_name, "operator new")
364 || strprefix(demangled_name, "operator delete")))
366 free(demangled_name);
369 else if (parameters->options().dynamic_list_cpp_typeinfo()
370 && (strprefix(demangled_name, "typeinfo name for")
371 || strprefix(demangled_name, "typeinfo for")))
373 free(demangled_name);
377 free(demangled_name);
380 // If exporting all symbols or building a shared library,
381 // and the symbol is defined in a regular object and is
382 // externally visible, we need to add it.
383 if ((parameters->options().export_dynamic() || parameters->options().shared())
384 && !this->is_from_dynobj()
385 && this->is_externally_visible())
391 // Return true if the final value of this symbol is known at link
395 Symbol::final_value_is_known() const
397 // If we are not generating an executable, then no final values are
398 // known, since they will change at runtime.
399 if (parameters->options().output_is_position_independent()
400 || parameters->options().relocatable())
403 // If the symbol is not from an object file, and is not undefined,
404 // then it is defined, and known.
405 if (this->source_ != FROM_OBJECT)
407 if (this->source_ != IS_UNDEFINED)
412 // If the symbol is from a dynamic object, then the final value
414 if (this->object()->is_dynamic())
417 // If the symbol is not undefined (it is defined or common),
418 // then the final value is known.
419 if (!this->is_undefined())
423 // If the symbol is undefined, then whether the final value is known
424 // depends on whether we are doing a static link. If we are doing a
425 // dynamic link, then the final value could be filled in at runtime.
426 // This could reasonably be the case for a weak undefined symbol.
427 return parameters->doing_static_link();
430 // Return the output section where this symbol is defined.
433 Symbol::output_section() const
435 switch (this->source_)
439 unsigned int shndx = this->u_.from_object.shndx;
440 if (shndx != elfcpp::SHN_UNDEF && this->is_ordinary_shndx_)
442 gold_assert(!this->u_.from_object.object->is_dynamic());
443 gold_assert(this->u_.from_object.object->pluginobj() == NULL);
444 Relobj* relobj = static_cast<Relobj*>(this->u_.from_object.object);
445 return relobj->output_section(shndx);
451 return this->u_.in_output_data.output_data->output_section();
453 case IN_OUTPUT_SEGMENT:
463 // Set the symbol's output section. This is used for symbols defined
464 // in scripts. This should only be called after the symbol table has
468 Symbol::set_output_section(Output_section* os)
470 switch (this->source_)
474 gold_assert(this->output_section() == os);
477 this->source_ = IN_OUTPUT_DATA;
478 this->u_.in_output_data.output_data = os;
479 this->u_.in_output_data.offset_is_from_end = false;
481 case IN_OUTPUT_SEGMENT:
488 // Class Symbol_table.
490 Symbol_table::Symbol_table(unsigned int count,
491 const Version_script_info& version_script)
492 : saw_undefined_(0), offset_(0), table_(count), namepool_(),
493 forwarders_(), commons_(), tls_commons_(), small_commons_(),
494 large_commons_(), forced_locals_(), warnings_(),
495 version_script_(version_script), gc_(NULL), icf_(NULL)
497 namepool_.reserve(count);
500 Symbol_table::~Symbol_table()
504 // The hash function. The key values are Stringpool keys.
507 Symbol_table::Symbol_table_hash::operator()(const Symbol_table_key& key) const
509 return key.first ^ key.second;
512 // The symbol table key equality function. This is called with
516 Symbol_table::Symbol_table_eq::operator()(const Symbol_table_key& k1,
517 const Symbol_table_key& k2) const
519 return k1.first == k2.first && k1.second == k2.second;
523 Symbol_table::is_section_folded(Object* obj, unsigned int shndx) const
525 return (parameters->options().icf_enabled()
526 && this->icf_->is_section_folded(obj, shndx));
529 // For symbols that have been listed with -u option, add them to the
530 // work list to avoid gc'ing them.
533 Symbol_table::gc_mark_undef_symbols()
535 for (options::String_set::const_iterator p =
536 parameters->options().undefined_begin();
537 p != parameters->options().undefined_end();
540 const char* name = p->c_str();
541 Symbol* sym = this->lookup(name);
542 gold_assert (sym != NULL);
543 if (sym->source() == Symbol::FROM_OBJECT
544 && !sym->object()->is_dynamic())
546 Relobj* obj = static_cast<Relobj*>(sym->object());
548 unsigned int shndx = sym->shndx(&is_ordinary);
551 gold_assert(this->gc_ != NULL);
552 this->gc_->worklist().push(Section_id(obj, shndx));
559 Symbol_table::gc_mark_symbol_for_shlib(Symbol* sym)
561 if (!sym->is_from_dynobj()
562 && sym->is_externally_visible())
564 //Add the object and section to the work list.
565 Relobj* obj = static_cast<Relobj*>(sym->object());
567 unsigned int shndx = sym->shndx(&is_ordinary);
568 if (is_ordinary && shndx != elfcpp::SHN_UNDEF)
570 gold_assert(this->gc_!= NULL);
571 this->gc_->worklist().push(Section_id(obj, shndx));
576 // When doing garbage collection, keep symbols that have been seen in
579 Symbol_table::gc_mark_dyn_syms(Symbol* sym)
581 if (sym->in_dyn() && sym->source() == Symbol::FROM_OBJECT
582 && !sym->object()->is_dynamic())
584 Relobj *obj = static_cast<Relobj*>(sym->object());
586 unsigned int shndx = sym->shndx(&is_ordinary);
587 if (is_ordinary && shndx != elfcpp::SHN_UNDEF)
589 gold_assert(this->gc_ != NULL);
590 this->gc_->worklist().push(Section_id(obj, shndx));
595 // Make TO a symbol which forwards to FROM.
598 Symbol_table::make_forwarder(Symbol* from, Symbol* to)
600 gold_assert(from != to);
601 gold_assert(!from->is_forwarder() && !to->is_forwarder());
602 this->forwarders_[from] = to;
603 from->set_forwarder();
606 // Resolve the forwards from FROM, returning the real symbol.
609 Symbol_table::resolve_forwards(const Symbol* from) const
611 gold_assert(from->is_forwarder());
612 Unordered_map<const Symbol*, Symbol*>::const_iterator p =
613 this->forwarders_.find(from);
614 gold_assert(p != this->forwarders_.end());
618 // Look up a symbol by name.
621 Symbol_table::lookup(const char* name, const char* version) const
623 Stringpool::Key name_key;
624 name = this->namepool_.find(name, &name_key);
628 Stringpool::Key version_key = 0;
631 version = this->namepool_.find(version, &version_key);
636 Symbol_table_key key(name_key, version_key);
637 Symbol_table::Symbol_table_type::const_iterator p = this->table_.find(key);
638 if (p == this->table_.end())
643 // Resolve a Symbol with another Symbol. This is only used in the
644 // unusual case where there are references to both an unversioned
645 // symbol and a symbol with a version, and we then discover that that
646 // version is the default version. Because this is unusual, we do
647 // this the slow way, by converting back to an ELF symbol.
649 template<int size, bool big_endian>
651 Symbol_table::resolve(Sized_symbol<size>* to, const Sized_symbol<size>* from)
653 unsigned char buf[elfcpp::Elf_sizes<size>::sym_size];
654 elfcpp::Sym_write<size, big_endian> esym(buf);
655 // We don't bother to set the st_name or the st_shndx field.
656 esym.put_st_value(from->value());
657 esym.put_st_size(from->symsize());
658 esym.put_st_info(from->binding(), from->type());
659 esym.put_st_other(from->visibility(), from->nonvis());
661 unsigned int shndx = from->shndx(&is_ordinary);
662 this->resolve(to, esym.sym(), shndx, is_ordinary, shndx, from->object(),
668 if (parameters->options().gc_sections())
669 this->gc_mark_dyn_syms(to);
672 // Record that a symbol is forced to be local by a version script or
676 Symbol_table::force_local(Symbol* sym)
678 if (!sym->is_defined() && !sym->is_common())
680 if (sym->is_forced_local())
682 // We already got this one.
685 sym->set_is_forced_local();
686 this->forced_locals_.push_back(sym);
689 // Adjust NAME for wrapping, and update *NAME_KEY if necessary. This
690 // is only called for undefined symbols, when at least one --wrap
694 Symbol_table::wrap_symbol(const char* name, Stringpool::Key* name_key)
696 // For some targets, we need to ignore a specific character when
697 // wrapping, and add it back later.
699 if (name[0] == parameters->target().wrap_char())
705 if (parameters->options().is_wrap(name))
707 // Turn NAME into __wrap_NAME.
714 // This will give us both the old and new name in NAMEPOOL_, but
715 // that is OK. Only the versions we need will wind up in the
716 // real string table in the output file.
717 return this->namepool_.add(s.c_str(), true, name_key);
720 const char* const real_prefix = "__real_";
721 const size_t real_prefix_length = strlen(real_prefix);
722 if (strncmp(name, real_prefix, real_prefix_length) == 0
723 && parameters->options().is_wrap(name + real_prefix_length))
725 // Turn __real_NAME into NAME.
729 s += name + real_prefix_length;
730 return this->namepool_.add(s.c_str(), true, name_key);
736 // This is called when we see a symbol NAME/VERSION, and the symbol
737 // already exists in the symbol table, and VERSION is marked as being
738 // the default version. SYM is the NAME/VERSION symbol we just added.
739 // DEFAULT_IS_NEW is true if this is the first time we have seen the
740 // symbol NAME/NULL. PDEF points to the entry for NAME/NULL.
742 template<int size, bool big_endian>
744 Symbol_table::define_default_version(Sized_symbol<size>* sym,
746 Symbol_table_type::iterator pdef)
750 // This is the first time we have seen NAME/NULL. Make
751 // NAME/NULL point to NAME/VERSION, and mark SYM as the default
754 sym->set_is_default();
756 else if (pdef->second == sym)
758 // NAME/NULL already points to NAME/VERSION. Don't mark the
759 // symbol as the default if it is not already the default.
763 // This is the unfortunate case where we already have entries
764 // for both NAME/VERSION and NAME/NULL. We now see a symbol
765 // NAME/VERSION where VERSION is the default version. We have
766 // already resolved this new symbol with the existing
767 // NAME/VERSION symbol.
769 // It's possible that NAME/NULL and NAME/VERSION are both
770 // defined in regular objects. This can only happen if one
771 // object file defines foo and another defines foo@@ver. This
772 // is somewhat obscure, but we call it a multiple definition
775 // It's possible that NAME/NULL actually has a version, in which
776 // case it won't be the same as VERSION. This happens with
777 // ver_test_7.so in the testsuite for the symbol t2_2. We see
778 // t2_2@@VER2, so we define both t2_2/VER2 and t2_2/NULL. We
779 // then see an unadorned t2_2 in an object file and give it
780 // version VER1 from the version script. This looks like a
781 // default definition for VER1, so it looks like we should merge
782 // t2_2/NULL with t2_2/VER1. That doesn't make sense, but it's
783 // not obvious that this is an error, either. So we just punt.
785 // If one of the symbols has non-default visibility, and the
786 // other is defined in a shared object, then they are different
789 // Otherwise, we just resolve the symbols as though they were
792 if (pdef->second->version() != NULL)
793 gold_assert(pdef->second->version() != sym->version());
794 else if (sym->visibility() != elfcpp::STV_DEFAULT
795 && pdef->second->is_from_dynobj())
797 else if (pdef->second->visibility() != elfcpp::STV_DEFAULT
798 && sym->is_from_dynobj())
802 const Sized_symbol<size>* symdef;
803 symdef = this->get_sized_symbol<size>(pdef->second);
804 Symbol_table::resolve<size, big_endian>(sym, symdef);
805 this->make_forwarder(pdef->second, sym);
807 sym->set_is_default();
812 // Add one symbol from OBJECT to the symbol table. NAME is symbol
813 // name and VERSION is the version; both are canonicalized. DEF is
814 // whether this is the default version. ST_SHNDX is the symbol's
815 // section index; IS_ORDINARY is whether this is a normal section
816 // rather than a special code.
818 // If IS_DEFAULT_VERSION is true, then this is the definition of a
819 // default version of a symbol. That means that any lookup of
820 // NAME/NULL and any lookup of NAME/VERSION should always return the
821 // same symbol. This is obvious for references, but in particular we
822 // want to do this for definitions: overriding NAME/NULL should also
823 // override NAME/VERSION. If we don't do that, it would be very hard
824 // to override functions in a shared library which uses versioning.
826 // We implement this by simply making both entries in the hash table
827 // point to the same Symbol structure. That is easy enough if this is
828 // the first time we see NAME/NULL or NAME/VERSION, but it is possible
829 // that we have seen both already, in which case they will both have
830 // independent entries in the symbol table. We can't simply change
831 // the symbol table entry, because we have pointers to the entries
832 // attached to the object files. So we mark the entry attached to the
833 // object file as a forwarder, and record it in the forwarders_ map.
834 // Note that entries in the hash table will never be marked as
837 // ORIG_ST_SHNDX and ST_SHNDX are almost always the same.
838 // ORIG_ST_SHNDX is the section index in the input file, or SHN_UNDEF
839 // for a special section code. ST_SHNDX may be modified if the symbol
840 // is defined in a section being discarded.
842 template<int size, bool big_endian>
844 Symbol_table::add_from_object(Object* object,
846 Stringpool::Key name_key,
848 Stringpool::Key version_key,
849 bool is_default_version,
850 const elfcpp::Sym<size, big_endian>& sym,
851 unsigned int st_shndx,
853 unsigned int orig_st_shndx)
855 // Print a message if this symbol is being traced.
856 if (parameters->options().is_trace_symbol(name))
858 if (orig_st_shndx == elfcpp::SHN_UNDEF)
859 gold_info(_("%s: reference to %s"), object->name().c_str(), name);
861 gold_info(_("%s: definition of %s"), object->name().c_str(), name);
864 // For an undefined symbol, we may need to adjust the name using
866 if (orig_st_shndx == elfcpp::SHN_UNDEF
867 && parameters->options().any_wrap())
869 const char* wrap_name = this->wrap_symbol(name, &name_key);
870 if (wrap_name != name)
872 // If we see a reference to malloc with version GLIBC_2.0,
873 // and we turn it into a reference to __wrap_malloc, then we
874 // discard the version number. Otherwise the user would be
875 // required to specify the correct version for
883 Symbol* const snull = NULL;
884 std::pair<typename Symbol_table_type::iterator, bool> ins =
885 this->table_.insert(std::make_pair(std::make_pair(name_key, version_key),
888 std::pair<typename Symbol_table_type::iterator, bool> insdefault =
889 std::make_pair(this->table_.end(), false);
890 if (is_default_version)
892 const Stringpool::Key vnull_key = 0;
893 insdefault = this->table_.insert(std::make_pair(std::make_pair(name_key,
898 // ins.first: an iterator, which is a pointer to a pair.
899 // ins.first->first: the key (a pair of name and version).
900 // ins.first->second: the value (Symbol*).
901 // ins.second: true if new entry was inserted, false if not.
903 Sized_symbol<size>* ret;
908 // We already have an entry for NAME/VERSION.
909 ret = this->get_sized_symbol<size>(ins.first->second);
910 gold_assert(ret != NULL);
912 was_undefined = ret->is_undefined();
913 was_common = ret->is_common();
915 this->resolve(ret, sym, st_shndx, is_ordinary, orig_st_shndx, object,
917 if (parameters->options().gc_sections())
918 this->gc_mark_dyn_syms(ret);
920 if (is_default_version)
921 this->define_default_version<size, big_endian>(ret, insdefault.second,
926 // This is the first time we have seen NAME/VERSION.
927 gold_assert(ins.first->second == NULL);
929 if (is_default_version && !insdefault.second)
931 // We already have an entry for NAME/NULL. If we override
932 // it, then change it to NAME/VERSION.
933 ret = this->get_sized_symbol<size>(insdefault.first->second);
935 was_undefined = ret->is_undefined();
936 was_common = ret->is_common();
938 this->resolve(ret, sym, st_shndx, is_ordinary, orig_st_shndx, object,
940 if (parameters->options().gc_sections())
941 this->gc_mark_dyn_syms(ret);
942 ins.first->second = ret;
946 was_undefined = false;
949 Sized_target<size, big_endian>* target =
950 parameters->sized_target<size, big_endian>();
951 if (!target->has_make_symbol())
952 ret = new Sized_symbol<size>();
955 ret = target->make_symbol();
958 // This means that we don't want a symbol table
960 if (!is_default_version)
961 this->table_.erase(ins.first);
964 this->table_.erase(insdefault.first);
965 // Inserting INSDEFAULT invalidated INS.
966 this->table_.erase(std::make_pair(name_key,
973 ret->init_object(name, version, object, sym, st_shndx, is_ordinary);
975 ins.first->second = ret;
976 if (is_default_version)
978 // This is the first time we have seen NAME/NULL. Point
979 // it at the new entry for NAME/VERSION.
980 gold_assert(insdefault.second);
981 insdefault.first->second = ret;
985 if (is_default_version)
986 ret->set_is_default();
989 // Record every time we see a new undefined symbol, to speed up
991 if (!was_undefined && ret->is_undefined())
992 ++this->saw_undefined_;
994 // Keep track of common symbols, to speed up common symbol
996 if (!was_common && ret->is_common())
998 if (ret->type() == elfcpp::STT_TLS)
999 this->tls_commons_.push_back(ret);
1000 else if (!is_ordinary
1001 && st_shndx == parameters->target().small_common_shndx())
1002 this->small_commons_.push_back(ret);
1003 else if (!is_ordinary
1004 && st_shndx == parameters->target().large_common_shndx())
1005 this->large_commons_.push_back(ret);
1007 this->commons_.push_back(ret);
1010 // If we're not doing a relocatable link, then any symbol with
1011 // hidden or internal visibility is local.
1012 if ((ret->visibility() == elfcpp::STV_HIDDEN
1013 || ret->visibility() == elfcpp::STV_INTERNAL)
1014 && (ret->binding() == elfcpp::STB_GLOBAL
1015 || ret->binding() == elfcpp::STB_GNU_UNIQUE
1016 || ret->binding() == elfcpp::STB_WEAK)
1017 && !parameters->options().relocatable())
1018 this->force_local(ret);
1023 // Add all the symbols in a relocatable object to the hash table.
1025 template<int size, bool big_endian>
1027 Symbol_table::add_from_relobj(
1028 Sized_relobj<size, big_endian>* relobj,
1029 const unsigned char* syms,
1031 size_t symndx_offset,
1032 const char* sym_names,
1033 size_t sym_name_size,
1034 typename Sized_relobj<size, big_endian>::Symbols* sympointers,
1039 gold_assert(size == parameters->target().get_size());
1041 const int sym_size = elfcpp::Elf_sizes<size>::sym_size;
1043 const bool just_symbols = relobj->just_symbols();
1045 const unsigned char* p = syms;
1046 for (size_t i = 0; i < count; ++i, p += sym_size)
1048 (*sympointers)[i] = NULL;
1050 elfcpp::Sym<size, big_endian> sym(p);
1052 unsigned int st_name = sym.get_st_name();
1053 if (st_name >= sym_name_size)
1055 relobj->error(_("bad global symbol name offset %u at %zu"),
1060 const char* name = sym_names + st_name;
1063 unsigned int st_shndx = relobj->adjust_sym_shndx(i + symndx_offset,
1066 unsigned int orig_st_shndx = st_shndx;
1068 orig_st_shndx = elfcpp::SHN_UNDEF;
1070 if (st_shndx != elfcpp::SHN_UNDEF)
1073 // A symbol defined in a section which we are not including must
1074 // be treated as an undefined symbol.
1075 bool is_defined_in_discarded_section = false;
1076 if (st_shndx != elfcpp::SHN_UNDEF
1078 && !relobj->is_section_included(st_shndx)
1079 && !this->is_section_folded(relobj, st_shndx))
1081 st_shndx = elfcpp::SHN_UNDEF;
1082 is_defined_in_discarded_section = true;
1085 // In an object file, an '@' in the name separates the symbol
1086 // name from the version name. If there are two '@' characters,
1087 // this is the default version.
1088 const char* ver = strchr(name, '@');
1089 Stringpool::Key ver_key = 0;
1091 // IS_DEFAULT_VERSION: is the version default?
1092 // IS_FORCED_LOCAL: is the symbol forced local?
1093 bool is_default_version = false;
1094 bool is_forced_local = false;
1098 // The symbol name is of the form foo@VERSION or foo@@VERSION
1099 namelen = ver - name;
1103 is_default_version = true;
1106 ver = this->namepool_.add(ver, true, &ver_key);
1108 // We don't want to assign a version to an undefined symbol,
1109 // even if it is listed in the version script. FIXME: What
1110 // about a common symbol?
1113 namelen = strlen(name);
1114 if (!this->version_script_.empty()
1115 && st_shndx != elfcpp::SHN_UNDEF)
1117 // The symbol name did not have a version, but the
1118 // version script may assign a version anyway.
1119 std::string version;
1121 if (this->version_script_.get_symbol_version(name, &version,
1125 is_forced_local = true;
1126 else if (!version.empty())
1128 ver = this->namepool_.add_with_length(version.c_str(),
1132 is_default_version = true;
1138 elfcpp::Sym<size, big_endian>* psym = &sym;
1139 unsigned char symbuf[sym_size];
1140 elfcpp::Sym<size, big_endian> sym2(symbuf);
1143 memcpy(symbuf, p, sym_size);
1144 elfcpp::Sym_write<size, big_endian> sw(symbuf);
1145 if (orig_st_shndx != elfcpp::SHN_UNDEF && is_ordinary)
1147 // Symbol values in object files are section relative.
1148 // This is normally what we want, but since here we are
1149 // converting the symbol to absolute we need to add the
1150 // section address. The section address in an object
1151 // file is normally zero, but people can use a linker
1152 // script to change it.
1153 sw.put_st_value(sym.get_st_value()
1154 + relobj->section_address(orig_st_shndx));
1156 st_shndx = elfcpp::SHN_ABS;
1157 is_ordinary = false;
1161 // Fix up visibility if object has no-export set.
1162 if (relobj->no_export()
1163 && (orig_st_shndx != elfcpp::SHN_UNDEF || !is_ordinary))
1165 // We may have copied symbol already above.
1168 memcpy(symbuf, p, sym_size);
1172 elfcpp::STV visibility = sym2.get_st_visibility();
1173 if (visibility == elfcpp::STV_DEFAULT
1174 || visibility == elfcpp::STV_PROTECTED)
1176 elfcpp::Sym_write<size, big_endian> sw(symbuf);
1177 unsigned char nonvis = sym2.get_st_nonvis();
1178 sw.put_st_other(elfcpp::STV_HIDDEN, nonvis);
1182 Stringpool::Key name_key;
1183 name = this->namepool_.add_with_length(name, namelen, true,
1186 Sized_symbol<size>* res;
1187 res = this->add_from_object(relobj, name, name_key, ver, ver_key,
1188 is_default_version, *psym, st_shndx,
1189 is_ordinary, orig_st_shndx);
1191 // If building a shared library using garbage collection, do not
1192 // treat externally visible symbols as garbage.
1193 if (parameters->options().gc_sections()
1194 && parameters->options().shared())
1195 this->gc_mark_symbol_for_shlib(res);
1197 if (is_forced_local)
1198 this->force_local(res);
1200 if (is_defined_in_discarded_section)
1201 res->set_is_defined_in_discarded_section();
1203 (*sympointers)[i] = res;
1207 // Add a symbol from a plugin-claimed file.
1209 template<int size, bool big_endian>
1211 Symbol_table::add_from_pluginobj(
1212 Sized_pluginobj<size, big_endian>* obj,
1215 elfcpp::Sym<size, big_endian>* sym)
1217 unsigned int st_shndx = sym->get_st_shndx();
1218 bool is_ordinary = st_shndx < elfcpp::SHN_LORESERVE;
1220 Stringpool::Key ver_key = 0;
1221 bool is_default_version = false;
1222 bool is_forced_local = false;
1226 ver = this->namepool_.add(ver, true, &ver_key);
1228 // We don't want to assign a version to an undefined symbol,
1229 // even if it is listed in the version script. FIXME: What
1230 // about a common symbol?
1233 if (!this->version_script_.empty()
1234 && st_shndx != elfcpp::SHN_UNDEF)
1236 // The symbol name did not have a version, but the
1237 // version script may assign a version anyway.
1238 std::string version;
1240 if (this->version_script_.get_symbol_version(name, &version,
1244 is_forced_local = true;
1245 else if (!version.empty())
1247 ver = this->namepool_.add_with_length(version.c_str(),
1251 is_default_version = true;
1257 Stringpool::Key name_key;
1258 name = this->namepool_.add(name, true, &name_key);
1260 Sized_symbol<size>* res;
1261 res = this->add_from_object(obj, name, name_key, ver, ver_key,
1262 is_default_version, *sym, st_shndx,
1263 is_ordinary, st_shndx);
1265 if (is_forced_local)
1266 this->force_local(res);
1271 // Add all the symbols in a dynamic object to the hash table.
1273 template<int size, bool big_endian>
1275 Symbol_table::add_from_dynobj(
1276 Sized_dynobj<size, big_endian>* dynobj,
1277 const unsigned char* syms,
1279 const char* sym_names,
1280 size_t sym_name_size,
1281 const unsigned char* versym,
1283 const std::vector<const char*>* version_map,
1284 typename Sized_relobj<size, big_endian>::Symbols* sympointers,
1289 gold_assert(size == parameters->target().get_size());
1291 if (dynobj->just_symbols())
1293 gold_error(_("--just-symbols does not make sense with a shared object"));
1297 if (versym != NULL && versym_size / 2 < count)
1299 dynobj->error(_("too few symbol versions"));
1303 const int sym_size = elfcpp::Elf_sizes<size>::sym_size;
1305 // We keep a list of all STT_OBJECT symbols, so that we can resolve
1306 // weak aliases. This is necessary because if the dynamic object
1307 // provides the same variable under two names, one of which is a
1308 // weak definition, and the regular object refers to the weak
1309 // definition, we have to put both the weak definition and the
1310 // strong definition into the dynamic symbol table. Given a weak
1311 // definition, the only way that we can find the corresponding
1312 // strong definition, if any, is to search the symbol table.
1313 std::vector<Sized_symbol<size>*> object_symbols;
1315 const unsigned char* p = syms;
1316 const unsigned char* vs = versym;
1317 for (size_t i = 0; i < count; ++i, p += sym_size, vs += 2)
1319 elfcpp::Sym<size, big_endian> sym(p);
1321 if (sympointers != NULL)
1322 (*sympointers)[i] = NULL;
1324 // Ignore symbols with local binding or that have
1325 // internal or hidden visibility.
1326 if (sym.get_st_bind() == elfcpp::STB_LOCAL
1327 || sym.get_st_visibility() == elfcpp::STV_INTERNAL
1328 || sym.get_st_visibility() == elfcpp::STV_HIDDEN)
1331 // A protected symbol in a shared library must be treated as a
1332 // normal symbol when viewed from outside the shared library.
1333 // Implement this by overriding the visibility here.
1334 elfcpp::Sym<size, big_endian>* psym = &sym;
1335 unsigned char symbuf[sym_size];
1336 elfcpp::Sym<size, big_endian> sym2(symbuf);
1337 if (sym.get_st_visibility() == elfcpp::STV_PROTECTED)
1339 memcpy(symbuf, p, sym_size);
1340 elfcpp::Sym_write<size, big_endian> sw(symbuf);
1341 sw.put_st_other(elfcpp::STV_DEFAULT, sym.get_st_nonvis());
1345 unsigned int st_name = psym->get_st_name();
1346 if (st_name >= sym_name_size)
1348 dynobj->error(_("bad symbol name offset %u at %zu"),
1353 const char* name = sym_names + st_name;
1356 unsigned int st_shndx = dynobj->adjust_sym_shndx(i, psym->get_st_shndx(),
1359 if (st_shndx != elfcpp::SHN_UNDEF)
1362 Sized_symbol<size>* res;
1366 Stringpool::Key name_key;
1367 name = this->namepool_.add(name, true, &name_key);
1368 res = this->add_from_object(dynobj, name, name_key, NULL, 0,
1369 false, *psym, st_shndx, is_ordinary,
1374 // Read the version information.
1376 unsigned int v = elfcpp::Swap<16, big_endian>::readval(vs);
1378 bool hidden = (v & elfcpp::VERSYM_HIDDEN) != 0;
1379 v &= elfcpp::VERSYM_VERSION;
1381 // The Sun documentation says that V can be VER_NDX_LOCAL,
1382 // or VER_NDX_GLOBAL, or a version index. The meaning of
1383 // VER_NDX_LOCAL is defined as "Symbol has local scope."
1384 // The old GNU linker will happily generate VER_NDX_LOCAL
1385 // for an undefined symbol. I don't know what the Sun
1386 // linker will generate.
1388 if (v == static_cast<unsigned int>(elfcpp::VER_NDX_LOCAL)
1389 && st_shndx != elfcpp::SHN_UNDEF)
1391 // This symbol should not be visible outside the object.
1395 // At this point we are definitely going to add this symbol.
1396 Stringpool::Key name_key;
1397 name = this->namepool_.add(name, true, &name_key);
1399 if (v == static_cast<unsigned int>(elfcpp::VER_NDX_LOCAL)
1400 || v == static_cast<unsigned int>(elfcpp::VER_NDX_GLOBAL))
1402 // This symbol does not have a version.
1403 res = this->add_from_object(dynobj, name, name_key, NULL, 0,
1404 false, *psym, st_shndx, is_ordinary,
1409 if (v >= version_map->size())
1411 dynobj->error(_("versym for symbol %zu out of range: %u"),
1416 const char* version = (*version_map)[v];
1417 if (version == NULL)
1419 dynobj->error(_("versym for symbol %zu has no name: %u"),
1424 Stringpool::Key version_key;
1425 version = this->namepool_.add(version, true, &version_key);
1427 // If this is an absolute symbol, and the version name
1428 // and symbol name are the same, then this is the
1429 // version definition symbol. These symbols exist to
1430 // support using -u to pull in particular versions. We
1431 // do not want to record a version for them.
1432 if (st_shndx == elfcpp::SHN_ABS
1434 && name_key == version_key)
1435 res = this->add_from_object(dynobj, name, name_key, NULL, 0,
1436 false, *psym, st_shndx, is_ordinary,
1440 const bool is_default_version =
1441 !hidden && st_shndx != elfcpp::SHN_UNDEF;
1442 res = this->add_from_object(dynobj, name, name_key, version,
1443 version_key, is_default_version,
1445 is_ordinary, st_shndx);
1450 // Note that it is possible that RES was overridden by an
1451 // earlier object, in which case it can't be aliased here.
1452 if (st_shndx != elfcpp::SHN_UNDEF
1454 && psym->get_st_type() == elfcpp::STT_OBJECT
1455 && res->source() == Symbol::FROM_OBJECT
1456 && res->object() == dynobj)
1457 object_symbols.push_back(res);
1459 if (sympointers != NULL)
1460 (*sympointers)[i] = res;
1463 this->record_weak_aliases(&object_symbols);
1466 // This is used to sort weak aliases. We sort them first by section
1467 // index, then by offset, then by weak ahead of strong.
1470 class Weak_alias_sorter
1473 bool operator()(const Sized_symbol<size>*, const Sized_symbol<size>*) const;
1478 Weak_alias_sorter<size>::operator()(const Sized_symbol<size>* s1,
1479 const Sized_symbol<size>* s2) const
1482 unsigned int s1_shndx = s1->shndx(&is_ordinary);
1483 gold_assert(is_ordinary);
1484 unsigned int s2_shndx = s2->shndx(&is_ordinary);
1485 gold_assert(is_ordinary);
1486 if (s1_shndx != s2_shndx)
1487 return s1_shndx < s2_shndx;
1489 if (s1->value() != s2->value())
1490 return s1->value() < s2->value();
1491 if (s1->binding() != s2->binding())
1493 if (s1->binding() == elfcpp::STB_WEAK)
1495 if (s2->binding() == elfcpp::STB_WEAK)
1498 return std::string(s1->name()) < std::string(s2->name());
1501 // SYMBOLS is a list of object symbols from a dynamic object. Look
1502 // for any weak aliases, and record them so that if we add the weak
1503 // alias to the dynamic symbol table, we also add the corresponding
1508 Symbol_table::record_weak_aliases(std::vector<Sized_symbol<size>*>* symbols)
1510 // Sort the vector by section index, then by offset, then by weak
1512 std::sort(symbols->begin(), symbols->end(), Weak_alias_sorter<size>());
1514 // Walk through the vector. For each weak definition, record
1516 for (typename std::vector<Sized_symbol<size>*>::const_iterator p =
1518 p != symbols->end();
1521 if ((*p)->binding() != elfcpp::STB_WEAK)
1524 // Build a circular list of weak aliases. Each symbol points to
1525 // the next one in the circular list.
1527 Sized_symbol<size>* from_sym = *p;
1528 typename std::vector<Sized_symbol<size>*>::const_iterator q;
1529 for (q = p + 1; q != symbols->end(); ++q)
1532 if ((*q)->shndx(&dummy) != from_sym->shndx(&dummy)
1533 || (*q)->value() != from_sym->value())
1536 this->weak_aliases_[from_sym] = *q;
1537 from_sym->set_has_alias();
1543 this->weak_aliases_[from_sym] = *p;
1544 from_sym->set_has_alias();
1551 // Create and return a specially defined symbol. If ONLY_IF_REF is
1552 // true, then only create the symbol if there is a reference to it.
1553 // If this does not return NULL, it sets *POLDSYM to the existing
1554 // symbol if there is one. This sets *RESOLVE_OLDSYM if we should
1555 // resolve the newly created symbol to the old one. This
1556 // canonicalizes *PNAME and *PVERSION.
1558 template<int size, bool big_endian>
1560 Symbol_table::define_special_symbol(const char** pname, const char** pversion,
1562 Sized_symbol<size>** poldsym,
1563 bool *resolve_oldsym)
1565 *resolve_oldsym = false;
1567 // If the caller didn't give us a version, see if we get one from
1568 // the version script.
1570 bool is_default_version = false;
1571 if (*pversion == NULL)
1574 if (this->version_script_.get_symbol_version(*pname, &v, &is_global))
1576 if (is_global && !v.empty())
1578 *pversion = v.c_str();
1579 // If we get the version from a version script, then we
1580 // are also the default version.
1581 is_default_version = true;
1587 Sized_symbol<size>* sym;
1589 bool add_to_table = false;
1590 typename Symbol_table_type::iterator add_loc = this->table_.end();
1591 bool add_def_to_table = false;
1592 typename Symbol_table_type::iterator add_def_loc = this->table_.end();
1596 oldsym = this->lookup(*pname, *pversion);
1597 if (oldsym == NULL && is_default_version)
1598 oldsym = this->lookup(*pname, NULL);
1599 if (oldsym == NULL || !oldsym->is_undefined())
1602 *pname = oldsym->name();
1603 if (!is_default_version)
1604 *pversion = oldsym->version();
1608 // Canonicalize NAME and VERSION.
1609 Stringpool::Key name_key;
1610 *pname = this->namepool_.add(*pname, true, &name_key);
1612 Stringpool::Key version_key = 0;
1613 if (*pversion != NULL)
1614 *pversion = this->namepool_.add(*pversion, true, &version_key);
1616 Symbol* const snull = NULL;
1617 std::pair<typename Symbol_table_type::iterator, bool> ins =
1618 this->table_.insert(std::make_pair(std::make_pair(name_key,
1622 std::pair<typename Symbol_table_type::iterator, bool> insdefault =
1623 std::make_pair(this->table_.end(), false);
1624 if (is_default_version)
1626 const Stringpool::Key vnull = 0;
1628 this->table_.insert(std::make_pair(std::make_pair(name_key,
1635 // We already have a symbol table entry for NAME/VERSION.
1636 oldsym = ins.first->second;
1637 gold_assert(oldsym != NULL);
1639 if (is_default_version)
1641 Sized_symbol<size>* soldsym =
1642 this->get_sized_symbol<size>(oldsym);
1643 this->define_default_version<size, big_endian>(soldsym,
1650 // We haven't seen this symbol before.
1651 gold_assert(ins.first->second == NULL);
1653 add_to_table = true;
1654 add_loc = ins.first;
1656 if (is_default_version && !insdefault.second)
1658 // We are adding NAME/VERSION, and it is the default
1659 // version. We already have an entry for NAME/NULL.
1660 oldsym = insdefault.first->second;
1661 *resolve_oldsym = true;
1667 if (is_default_version)
1669 add_def_to_table = true;
1670 add_def_loc = insdefault.first;
1676 const Target& target = parameters->target();
1677 if (!target.has_make_symbol())
1678 sym = new Sized_symbol<size>();
1681 Sized_target<size, big_endian>* sized_target =
1682 parameters->sized_target<size, big_endian>();
1683 sym = sized_target->make_symbol();
1689 add_loc->second = sym;
1691 gold_assert(oldsym != NULL);
1693 if (add_def_to_table)
1694 add_def_loc->second = sym;
1696 *poldsym = this->get_sized_symbol<size>(oldsym);
1701 // Define a symbol based on an Output_data.
1704 Symbol_table::define_in_output_data(const char* name,
1705 const char* version,
1711 elfcpp::STB binding,
1712 elfcpp::STV visibility,
1713 unsigned char nonvis,
1714 bool offset_is_from_end,
1717 if (parameters->target().get_size() == 32)
1719 #if defined(HAVE_TARGET_32_LITTLE) || defined(HAVE_TARGET_32_BIG)
1720 return this->do_define_in_output_data<32>(name, version, defined, od,
1721 value, symsize, type, binding,
1729 else if (parameters->target().get_size() == 64)
1731 #if defined(HAVE_TARGET_64_LITTLE) || defined(HAVE_TARGET_64_BIG)
1732 return this->do_define_in_output_data<64>(name, version, defined, od,
1733 value, symsize, type, binding,
1745 // Define a symbol in an Output_data, sized version.
1749 Symbol_table::do_define_in_output_data(
1751 const char* version,
1754 typename elfcpp::Elf_types<size>::Elf_Addr value,
1755 typename elfcpp::Elf_types<size>::Elf_WXword symsize,
1757 elfcpp::STB binding,
1758 elfcpp::STV visibility,
1759 unsigned char nonvis,
1760 bool offset_is_from_end,
1763 Sized_symbol<size>* sym;
1764 Sized_symbol<size>* oldsym;
1765 bool resolve_oldsym;
1767 if (parameters->target().is_big_endian())
1769 #if defined(HAVE_TARGET_32_BIG) || defined(HAVE_TARGET_64_BIG)
1770 sym = this->define_special_symbol<size, true>(&name, &version,
1771 only_if_ref, &oldsym,
1779 #if defined(HAVE_TARGET_32_LITTLE) || defined(HAVE_TARGET_64_LITTLE)
1780 sym = this->define_special_symbol<size, false>(&name, &version,
1781 only_if_ref, &oldsym,
1791 sym->init_output_data(name, version, od, value, symsize, type, binding,
1792 visibility, nonvis, offset_is_from_end);
1796 if (binding == elfcpp::STB_LOCAL
1797 || this->version_script_.symbol_is_local(name))
1798 this->force_local(sym);
1799 else if (version != NULL)
1800 sym->set_is_default();
1804 if (Symbol_table::should_override_with_special(oldsym, defined))
1805 this->override_with_special(oldsym, sym);
1816 // Define a symbol based on an Output_segment.
1819 Symbol_table::define_in_output_segment(const char* name,
1820 const char* version,
1826 elfcpp::STB binding,
1827 elfcpp::STV visibility,
1828 unsigned char nonvis,
1829 Symbol::Segment_offset_base offset_base,
1832 if (parameters->target().get_size() == 32)
1834 #if defined(HAVE_TARGET_32_LITTLE) || defined(HAVE_TARGET_32_BIG)
1835 return this->do_define_in_output_segment<32>(name, version, defined, os,
1836 value, symsize, type,
1837 binding, visibility, nonvis,
1838 offset_base, only_if_ref);
1843 else if (parameters->target().get_size() == 64)
1845 #if defined(HAVE_TARGET_64_LITTLE) || defined(HAVE_TARGET_64_BIG)
1846 return this->do_define_in_output_segment<64>(name, version, defined, os,
1847 value, symsize, type,
1848 binding, visibility, nonvis,
1849 offset_base, only_if_ref);
1858 // Define a symbol in an Output_segment, sized version.
1862 Symbol_table::do_define_in_output_segment(
1864 const char* version,
1867 typename elfcpp::Elf_types<size>::Elf_Addr value,
1868 typename elfcpp::Elf_types<size>::Elf_WXword symsize,
1870 elfcpp::STB binding,
1871 elfcpp::STV visibility,
1872 unsigned char nonvis,
1873 Symbol::Segment_offset_base offset_base,
1876 Sized_symbol<size>* sym;
1877 Sized_symbol<size>* oldsym;
1878 bool resolve_oldsym;
1880 if (parameters->target().is_big_endian())
1882 #if defined(HAVE_TARGET_32_BIG) || defined(HAVE_TARGET_64_BIG)
1883 sym = this->define_special_symbol<size, true>(&name, &version,
1884 only_if_ref, &oldsym,
1892 #if defined(HAVE_TARGET_32_LITTLE) || defined(HAVE_TARGET_64_LITTLE)
1893 sym = this->define_special_symbol<size, false>(&name, &version,
1894 only_if_ref, &oldsym,
1904 sym->init_output_segment(name, version, os, value, symsize, type, binding,
1905 visibility, nonvis, offset_base);
1909 if (binding == elfcpp::STB_LOCAL
1910 || this->version_script_.symbol_is_local(name))
1911 this->force_local(sym);
1912 else if (version != NULL)
1913 sym->set_is_default();
1917 if (Symbol_table::should_override_with_special(oldsym, defined))
1918 this->override_with_special(oldsym, sym);
1929 // Define a special symbol with a constant value. It is a multiple
1930 // definition error if this symbol is already defined.
1933 Symbol_table::define_as_constant(const char* name,
1934 const char* version,
1939 elfcpp::STB binding,
1940 elfcpp::STV visibility,
1941 unsigned char nonvis,
1943 bool force_override)
1945 if (parameters->target().get_size() == 32)
1947 #if defined(HAVE_TARGET_32_LITTLE) || defined(HAVE_TARGET_32_BIG)
1948 return this->do_define_as_constant<32>(name, version, defined, value,
1949 symsize, type, binding,
1950 visibility, nonvis, only_if_ref,
1956 else if (parameters->target().get_size() == 64)
1958 #if defined(HAVE_TARGET_64_LITTLE) || defined(HAVE_TARGET_64_BIG)
1959 return this->do_define_as_constant<64>(name, version, defined, value,
1960 symsize, type, binding,
1961 visibility, nonvis, only_if_ref,
1971 // Define a symbol as a constant, sized version.
1975 Symbol_table::do_define_as_constant(
1977 const char* version,
1979 typename elfcpp::Elf_types<size>::Elf_Addr value,
1980 typename elfcpp::Elf_types<size>::Elf_WXword symsize,
1982 elfcpp::STB binding,
1983 elfcpp::STV visibility,
1984 unsigned char nonvis,
1986 bool force_override)
1988 Sized_symbol<size>* sym;
1989 Sized_symbol<size>* oldsym;
1990 bool resolve_oldsym;
1992 if (parameters->target().is_big_endian())
1994 #if defined(HAVE_TARGET_32_BIG) || defined(HAVE_TARGET_64_BIG)
1995 sym = this->define_special_symbol<size, true>(&name, &version,
1996 only_if_ref, &oldsym,
2004 #if defined(HAVE_TARGET_32_LITTLE) || defined(HAVE_TARGET_64_LITTLE)
2005 sym = this->define_special_symbol<size, false>(&name, &version,
2006 only_if_ref, &oldsym,
2016 sym->init_constant(name, version, value, symsize, type, binding, visibility,
2021 // Version symbols are absolute symbols with name == version.
2022 // We don't want to force them to be local.
2023 if ((version == NULL
2026 && (binding == elfcpp::STB_LOCAL
2027 || this->version_script_.symbol_is_local(name)))
2028 this->force_local(sym);
2029 else if (version != NULL
2030 && (name != version || value != 0))
2031 sym->set_is_default();
2036 || Symbol_table::should_override_with_special(oldsym, defined))
2037 this->override_with_special(oldsym, sym);
2048 // Define a set of symbols in output sections.
2051 Symbol_table::define_symbols(const Layout* layout, int count,
2052 const Define_symbol_in_section* p,
2055 for (int i = 0; i < count; ++i, ++p)
2057 Output_section* os = layout->find_output_section(p->output_section);
2059 this->define_in_output_data(p->name, NULL, PREDEFINED, os, p->value,
2060 p->size, p->type, p->binding,
2061 p->visibility, p->nonvis,
2062 p->offset_is_from_end,
2063 only_if_ref || p->only_if_ref);
2065 this->define_as_constant(p->name, NULL, PREDEFINED, 0, p->size,
2066 p->type, p->binding, p->visibility, p->nonvis,
2067 only_if_ref || p->only_if_ref,
2072 // Define a set of symbols in output segments.
2075 Symbol_table::define_symbols(const Layout* layout, int count,
2076 const Define_symbol_in_segment* p,
2079 for (int i = 0; i < count; ++i, ++p)
2081 Output_segment* os = layout->find_output_segment(p->segment_type,
2082 p->segment_flags_set,
2083 p->segment_flags_clear);
2085 this->define_in_output_segment(p->name, NULL, PREDEFINED, os, p->value,
2086 p->size, p->type, p->binding,
2087 p->visibility, p->nonvis,
2089 only_if_ref || p->only_if_ref);
2091 this->define_as_constant(p->name, NULL, PREDEFINED, 0, p->size,
2092 p->type, p->binding, p->visibility, p->nonvis,
2093 only_if_ref || p->only_if_ref,
2098 // Define CSYM using a COPY reloc. POSD is the Output_data where the
2099 // symbol should be defined--typically a .dyn.bss section. VALUE is
2100 // the offset within POSD.
2104 Symbol_table::define_with_copy_reloc(
2105 Sized_symbol<size>* csym,
2107 typename elfcpp::Elf_types<size>::Elf_Addr value)
2109 gold_assert(csym->is_from_dynobj());
2110 gold_assert(!csym->is_copied_from_dynobj());
2111 Object* object = csym->object();
2112 gold_assert(object->is_dynamic());
2113 Dynobj* dynobj = static_cast<Dynobj*>(object);
2115 // Our copied variable has to override any variable in a shared
2117 elfcpp::STB binding = csym->binding();
2118 if (binding == elfcpp::STB_WEAK)
2119 binding = elfcpp::STB_GLOBAL;
2121 this->define_in_output_data(csym->name(), csym->version(), COPY,
2122 posd, value, csym->symsize(),
2123 csym->type(), binding,
2124 csym->visibility(), csym->nonvis(),
2127 csym->set_is_copied_from_dynobj();
2128 csym->set_needs_dynsym_entry();
2130 this->copied_symbol_dynobjs_[csym] = dynobj;
2132 // We have now defined all aliases, but we have not entered them all
2133 // in the copied_symbol_dynobjs_ map.
2134 if (csym->has_alias())
2139 sym = this->weak_aliases_[sym];
2142 gold_assert(sym->output_data() == posd);
2144 sym->set_is_copied_from_dynobj();
2145 this->copied_symbol_dynobjs_[sym] = dynobj;
2150 // SYM is defined using a COPY reloc. Return the dynamic object where
2151 // the original definition was found.
2154 Symbol_table::get_copy_source(const Symbol* sym) const
2156 gold_assert(sym->is_copied_from_dynobj());
2157 Copied_symbol_dynobjs::const_iterator p =
2158 this->copied_symbol_dynobjs_.find(sym);
2159 gold_assert(p != this->copied_symbol_dynobjs_.end());
2163 // Add any undefined symbols named on the command line.
2166 Symbol_table::add_undefined_symbols_from_command_line()
2168 if (parameters->options().any_undefined())
2170 if (parameters->target().get_size() == 32)
2172 #if defined(HAVE_TARGET_32_LITTLE) || defined(HAVE_TARGET_32_BIG)
2173 this->do_add_undefined_symbols_from_command_line<32>();
2178 else if (parameters->target().get_size() == 64)
2180 #if defined(HAVE_TARGET_64_LITTLE) || defined(HAVE_TARGET_64_BIG)
2181 this->do_add_undefined_symbols_from_command_line<64>();
2193 Symbol_table::do_add_undefined_symbols_from_command_line()
2195 for (options::String_set::const_iterator p =
2196 parameters->options().undefined_begin();
2197 p != parameters->options().undefined_end();
2200 const char* name = p->c_str();
2202 if (this->lookup(name) != NULL)
2205 const char* version = NULL;
2207 Sized_symbol<size>* sym;
2208 Sized_symbol<size>* oldsym;
2209 bool resolve_oldsym;
2210 if (parameters->target().is_big_endian())
2212 #if defined(HAVE_TARGET_32_BIG) || defined(HAVE_TARGET_64_BIG)
2213 sym = this->define_special_symbol<size, true>(&name, &version,
2222 #if defined(HAVE_TARGET_32_LITTLE) || defined(HAVE_TARGET_64_LITTLE)
2223 sym = this->define_special_symbol<size, false>(&name, &version,
2231 gold_assert(oldsym == NULL);
2233 sym->init_undefined(name, version, elfcpp::STT_NOTYPE, elfcpp::STB_GLOBAL,
2234 elfcpp::STV_DEFAULT, 0);
2235 ++this->saw_undefined_;
2239 // Set the dynamic symbol indexes. INDEX is the index of the first
2240 // global dynamic symbol. Pointers to the symbols are stored into the
2241 // vector SYMS. The names are added to DYNPOOL. This returns an
2242 // updated dynamic symbol index.
2245 Symbol_table::set_dynsym_indexes(unsigned int index,
2246 std::vector<Symbol*>* syms,
2247 Stringpool* dynpool,
2250 for (Symbol_table_type::iterator p = this->table_.begin();
2251 p != this->table_.end();
2254 Symbol* sym = p->second;
2256 // Note that SYM may already have a dynamic symbol index, since
2257 // some symbols appear more than once in the symbol table, with
2258 // and without a version.
2260 if (!sym->should_add_dynsym_entry(this))
2261 sym->set_dynsym_index(-1U);
2262 else if (!sym->has_dynsym_index())
2264 sym->set_dynsym_index(index);
2266 syms->push_back(sym);
2267 dynpool->add(sym->name(), false, NULL);
2269 // Record any version information.
2270 if (sym->version() != NULL)
2271 versions->record_version(this, dynpool, sym);
2273 // If the symbol is defined in a dynamic object and is
2274 // referenced in a regular object, then mark the dynamic
2275 // object as needed. This is used to implement --as-needed.
2276 if (sym->is_from_dynobj() && sym->in_reg())
2277 sym->object()->set_is_needed();
2281 // Finish up the versions. In some cases this may add new dynamic
2283 index = versions->finalize(this, index, syms);
2288 // Set the final values for all the symbols. The index of the first
2289 // global symbol in the output file is *PLOCAL_SYMCOUNT. Record the
2290 // file offset OFF. Add their names to POOL. Return the new file
2291 // offset. Update *PLOCAL_SYMCOUNT if necessary.
2294 Symbol_table::finalize(off_t off, off_t dynoff, size_t dyn_global_index,
2295 size_t dyncount, Stringpool* pool,
2296 unsigned int *plocal_symcount)
2300 gold_assert(*plocal_symcount != 0);
2301 this->first_global_index_ = *plocal_symcount;
2303 this->dynamic_offset_ = dynoff;
2304 this->first_dynamic_global_index_ = dyn_global_index;
2305 this->dynamic_count_ = dyncount;
2307 if (parameters->target().get_size() == 32)
2309 #if defined(HAVE_TARGET_32_BIG) || defined(HAVE_TARGET_32_LITTLE)
2310 ret = this->sized_finalize<32>(off, pool, plocal_symcount);
2315 else if (parameters->target().get_size() == 64)
2317 #if defined(HAVE_TARGET_64_BIG) || defined(HAVE_TARGET_64_LITTLE)
2318 ret = this->sized_finalize<64>(off, pool, plocal_symcount);
2326 // Now that we have the final symbol table, we can reliably note
2327 // which symbols should get warnings.
2328 this->warnings_.note_warnings(this);
2333 // SYM is going into the symbol table at *PINDEX. Add the name to
2334 // POOL, update *PINDEX and *POFF.
2338 Symbol_table::add_to_final_symtab(Symbol* sym, Stringpool* pool,
2339 unsigned int* pindex, off_t* poff)
2341 sym->set_symtab_index(*pindex);
2342 pool->add(sym->name(), false, NULL);
2344 *poff += elfcpp::Elf_sizes<size>::sym_size;
2347 // Set the final value for all the symbols. This is called after
2348 // Layout::finalize, so all the output sections have their final
2353 Symbol_table::sized_finalize(off_t off, Stringpool* pool,
2354 unsigned int* plocal_symcount)
2356 off = align_address(off, size >> 3);
2357 this->offset_ = off;
2359 unsigned int index = *plocal_symcount;
2360 const unsigned int orig_index = index;
2362 // First do all the symbols which have been forced to be local, as
2363 // they must appear before all global symbols.
2364 for (Forced_locals::iterator p = this->forced_locals_.begin();
2365 p != this->forced_locals_.end();
2369 gold_assert(sym->is_forced_local());
2370 if (this->sized_finalize_symbol<size>(sym))
2372 this->add_to_final_symtab<size>(sym, pool, &index, &off);
2377 // Now do all the remaining symbols.
2378 for (Symbol_table_type::iterator p = this->table_.begin();
2379 p != this->table_.end();
2382 Symbol* sym = p->second;
2383 if (this->sized_finalize_symbol<size>(sym))
2384 this->add_to_final_symtab<size>(sym, pool, &index, &off);
2387 this->output_count_ = index - orig_index;
2392 // Compute the final value of SYM and store status in location PSTATUS.
2393 // During relaxation, this may be called multiple times for a symbol to
2394 // compute its would-be final value in each relaxation pass.
2397 typename Sized_symbol<size>::Value_type
2398 Symbol_table::compute_final_value(
2399 const Sized_symbol<size>* sym,
2400 Compute_final_value_status* pstatus) const
2402 typedef typename Sized_symbol<size>::Value_type Value_type;
2405 switch (sym->source())
2407 case Symbol::FROM_OBJECT:
2410 unsigned int shndx = sym->shndx(&is_ordinary);
2413 && shndx != elfcpp::SHN_ABS
2414 && !Symbol::is_common_shndx(shndx))
2416 *pstatus = CFVS_UNSUPPORTED_SYMBOL_SECTION;
2420 Object* symobj = sym->object();
2421 if (symobj->is_dynamic())
2424 shndx = elfcpp::SHN_UNDEF;
2426 else if (symobj->pluginobj() != NULL)
2429 shndx = elfcpp::SHN_UNDEF;
2431 else if (shndx == elfcpp::SHN_UNDEF)
2433 else if (!is_ordinary
2434 && (shndx == elfcpp::SHN_ABS
2435 || Symbol::is_common_shndx(shndx)))
2436 value = sym->value();
2439 Relobj* relobj = static_cast<Relobj*>(symobj);
2440 Output_section* os = relobj->output_section(shndx);
2442 if (this->is_section_folded(relobj, shndx))
2444 gold_assert(os == NULL);
2445 // Get the os of the section it is folded onto.
2446 Section_id folded = this->icf_->get_folded_section(relobj,
2448 gold_assert(folded.first != NULL);
2449 Relobj* folded_obj = reinterpret_cast<Relobj*>(folded.first);
2450 unsigned folded_shndx = folded.second;
2452 os = folded_obj->output_section(folded_shndx);
2453 gold_assert(os != NULL);
2455 // Replace (relobj, shndx) with canonical ICF input section.
2456 shndx = folded_shndx;
2457 relobj = folded_obj;
2460 uint64_t secoff64 = relobj->output_section_offset(shndx);
2463 bool static_or_reloc = (parameters->doing_static_link() ||
2464 parameters->options().relocatable());
2465 gold_assert(static_or_reloc || sym->dynsym_index() == -1U);
2467 *pstatus = CFVS_NO_OUTPUT_SECTION;
2471 if (secoff64 == -1ULL)
2473 // The section needs special handling (e.g., a merge section).
2475 value = os->output_address(relobj, shndx, sym->value());
2480 convert_types<Value_type, uint64_t>(secoff64);
2481 if (sym->type() == elfcpp::STT_TLS)
2482 value = sym->value() + os->tls_offset() + secoff;
2484 value = sym->value() + os->address() + secoff;
2490 case Symbol::IN_OUTPUT_DATA:
2492 Output_data* od = sym->output_data();
2493 value = sym->value();
2494 if (sym->type() != elfcpp::STT_TLS)
2495 value += od->address();
2498 Output_section* os = od->output_section();
2499 gold_assert(os != NULL);
2500 value += os->tls_offset() + (od->address() - os->address());
2502 if (sym->offset_is_from_end())
2503 value += od->data_size();
2507 case Symbol::IN_OUTPUT_SEGMENT:
2509 Output_segment* os = sym->output_segment();
2510 value = sym->value();
2511 if (sym->type() != elfcpp::STT_TLS)
2512 value += os->vaddr();
2513 switch (sym->offset_base())
2515 case Symbol::SEGMENT_START:
2517 case Symbol::SEGMENT_END:
2518 value += os->memsz();
2520 case Symbol::SEGMENT_BSS:
2521 value += os->filesz();
2529 case Symbol::IS_CONSTANT:
2530 value = sym->value();
2533 case Symbol::IS_UNDEFINED:
2545 // Finalize the symbol SYM. This returns true if the symbol should be
2546 // added to the symbol table, false otherwise.
2550 Symbol_table::sized_finalize_symbol(Symbol* unsized_sym)
2552 typedef typename Sized_symbol<size>::Value_type Value_type;
2554 Sized_symbol<size>* sym = static_cast<Sized_symbol<size>*>(unsized_sym);
2556 // The default version of a symbol may appear twice in the symbol
2557 // table. We only need to finalize it once.
2558 if (sym->has_symtab_index())
2563 gold_assert(!sym->has_symtab_index());
2564 sym->set_symtab_index(-1U);
2565 gold_assert(sym->dynsym_index() == -1U);
2569 // Compute final symbol value.
2570 Compute_final_value_status status;
2571 Value_type value = this->compute_final_value(sym, &status);
2577 case CFVS_UNSUPPORTED_SYMBOL_SECTION:
2580 unsigned int shndx = sym->shndx(&is_ordinary);
2581 gold_error(_("%s: unsupported symbol section 0x%x"),
2582 sym->demangled_name().c_str(), shndx);
2585 case CFVS_NO_OUTPUT_SECTION:
2586 sym->set_symtab_index(-1U);
2592 sym->set_value(value);
2594 if (parameters->options().strip_all()
2595 || !parameters->options().should_retain_symbol(sym->name()))
2597 sym->set_symtab_index(-1U);
2604 // Write out the global symbols.
2607 Symbol_table::write_globals(const Stringpool* sympool,
2608 const Stringpool* dynpool,
2609 Output_symtab_xindex* symtab_xindex,
2610 Output_symtab_xindex* dynsym_xindex,
2611 Output_file* of) const
2613 switch (parameters->size_and_endianness())
2615 #ifdef HAVE_TARGET_32_LITTLE
2616 case Parameters::TARGET_32_LITTLE:
2617 this->sized_write_globals<32, false>(sympool, dynpool, symtab_xindex,
2621 #ifdef HAVE_TARGET_32_BIG
2622 case Parameters::TARGET_32_BIG:
2623 this->sized_write_globals<32, true>(sympool, dynpool, symtab_xindex,
2627 #ifdef HAVE_TARGET_64_LITTLE
2628 case Parameters::TARGET_64_LITTLE:
2629 this->sized_write_globals<64, false>(sympool, dynpool, symtab_xindex,
2633 #ifdef HAVE_TARGET_64_BIG
2634 case Parameters::TARGET_64_BIG:
2635 this->sized_write_globals<64, true>(sympool, dynpool, symtab_xindex,
2644 // Write out the global symbols.
2646 template<int size, bool big_endian>
2648 Symbol_table::sized_write_globals(const Stringpool* sympool,
2649 const Stringpool* dynpool,
2650 Output_symtab_xindex* symtab_xindex,
2651 Output_symtab_xindex* dynsym_xindex,
2652 Output_file* of) const
2654 const Target& target = parameters->target();
2656 const int sym_size = elfcpp::Elf_sizes<size>::sym_size;
2658 const unsigned int output_count = this->output_count_;
2659 const section_size_type oview_size = output_count * sym_size;
2660 const unsigned int first_global_index = this->first_global_index_;
2661 unsigned char* psyms;
2662 if (this->offset_ == 0 || output_count == 0)
2665 psyms = of->get_output_view(this->offset_, oview_size);
2667 const unsigned int dynamic_count = this->dynamic_count_;
2668 const section_size_type dynamic_size = dynamic_count * sym_size;
2669 const unsigned int first_dynamic_global_index =
2670 this->first_dynamic_global_index_;
2671 unsigned char* dynamic_view;
2672 if (this->dynamic_offset_ == 0 || dynamic_count == 0)
2673 dynamic_view = NULL;
2675 dynamic_view = of->get_output_view(this->dynamic_offset_, dynamic_size);
2677 for (Symbol_table_type::const_iterator p = this->table_.begin();
2678 p != this->table_.end();
2681 Sized_symbol<size>* sym = static_cast<Sized_symbol<size>*>(p->second);
2683 // Possibly warn about unresolved symbols in shared libraries.
2684 this->warn_about_undefined_dynobj_symbol(sym);
2686 unsigned int sym_index = sym->symtab_index();
2687 unsigned int dynsym_index;
2688 if (dynamic_view == NULL)
2691 dynsym_index = sym->dynsym_index();
2693 if (sym_index == -1U && dynsym_index == -1U)
2695 // This symbol is not included in the output file.
2700 typename elfcpp::Elf_types<size>::Elf_Addr sym_value = sym->value();
2701 typename elfcpp::Elf_types<size>::Elf_Addr dynsym_value = sym_value;
2702 elfcpp::STB binding = sym->binding();
2703 switch (sym->source())
2705 case Symbol::FROM_OBJECT:
2708 unsigned int in_shndx = sym->shndx(&is_ordinary);
2711 && in_shndx != elfcpp::SHN_ABS
2712 && !Symbol::is_common_shndx(in_shndx))
2714 gold_error(_("%s: unsupported symbol section 0x%x"),
2715 sym->demangled_name().c_str(), in_shndx);
2720 Object* symobj = sym->object();
2721 if (symobj->is_dynamic())
2723 if (sym->needs_dynsym_value())
2724 dynsym_value = target.dynsym_value(sym);
2725 shndx = elfcpp::SHN_UNDEF;
2726 if (sym->is_undef_binding_weak())
2727 binding = elfcpp::STB_WEAK;
2729 else if (symobj->pluginobj() != NULL)
2730 shndx = elfcpp::SHN_UNDEF;
2731 else if (in_shndx == elfcpp::SHN_UNDEF
2733 && (in_shndx == elfcpp::SHN_ABS
2734 || Symbol::is_common_shndx(in_shndx))))
2738 Relobj* relobj = static_cast<Relobj*>(symobj);
2739 Output_section* os = relobj->output_section(in_shndx);
2740 if (this->is_section_folded(relobj, in_shndx))
2742 // This global symbol must be written out even though
2744 // Get the os of the section it is folded onto.
2746 this->icf_->get_folded_section(relobj, in_shndx);
2747 gold_assert(folded.first !=NULL);
2748 Relobj* folded_obj =
2749 reinterpret_cast<Relobj*>(folded.first);
2750 os = folded_obj->output_section(folded.second);
2751 gold_assert(os != NULL);
2753 gold_assert(os != NULL);
2754 shndx = os->out_shndx();
2756 if (shndx >= elfcpp::SHN_LORESERVE)
2758 if (sym_index != -1U)
2759 symtab_xindex->add(sym_index, shndx);
2760 if (dynsym_index != -1U)
2761 dynsym_xindex->add(dynsym_index, shndx);
2762 shndx = elfcpp::SHN_XINDEX;
2765 // In object files symbol values are section
2767 if (parameters->options().relocatable())
2768 sym_value -= os->address();
2774 case Symbol::IN_OUTPUT_DATA:
2775 shndx = sym->output_data()->out_shndx();
2776 if (shndx >= elfcpp::SHN_LORESERVE)
2778 if (sym_index != -1U)
2779 symtab_xindex->add(sym_index, shndx);
2780 if (dynsym_index != -1U)
2781 dynsym_xindex->add(dynsym_index, shndx);
2782 shndx = elfcpp::SHN_XINDEX;
2786 case Symbol::IN_OUTPUT_SEGMENT:
2787 shndx = elfcpp::SHN_ABS;
2790 case Symbol::IS_CONSTANT:
2791 shndx = elfcpp::SHN_ABS;
2794 case Symbol::IS_UNDEFINED:
2795 shndx = elfcpp::SHN_UNDEF;
2802 if (sym_index != -1U)
2804 sym_index -= first_global_index;
2805 gold_assert(sym_index < output_count);
2806 unsigned char* ps = psyms + (sym_index * sym_size);
2807 this->sized_write_symbol<size, big_endian>(sym, sym_value, shndx,
2808 binding, sympool, ps);
2811 if (dynsym_index != -1U)
2813 dynsym_index -= first_dynamic_global_index;
2814 gold_assert(dynsym_index < dynamic_count);
2815 unsigned char* pd = dynamic_view + (dynsym_index * sym_size);
2816 this->sized_write_symbol<size, big_endian>(sym, dynsym_value, shndx,
2817 binding, dynpool, pd);
2821 of->write_output_view(this->offset_, oview_size, psyms);
2822 if (dynamic_view != NULL)
2823 of->write_output_view(this->dynamic_offset_, dynamic_size, dynamic_view);
2826 // Write out the symbol SYM, in section SHNDX, to P. POOL is the
2827 // strtab holding the name.
2829 template<int size, bool big_endian>
2831 Symbol_table::sized_write_symbol(
2832 Sized_symbol<size>* sym,
2833 typename elfcpp::Elf_types<size>::Elf_Addr value,
2835 elfcpp::STB binding,
2836 const Stringpool* pool,
2837 unsigned char* p) const
2839 elfcpp::Sym_write<size, big_endian> osym(p);
2840 osym.put_st_name(pool->get_offset(sym->name()));
2841 osym.put_st_value(value);
2842 // Use a symbol size of zero for undefined symbols from shared libraries.
2843 if (shndx == elfcpp::SHN_UNDEF && sym->is_from_dynobj())
2844 osym.put_st_size(0);
2846 osym.put_st_size(sym->symsize());
2847 elfcpp::STT type = sym->type();
2848 // Turn IFUNC symbols from shared libraries into normal FUNC symbols.
2849 if (type == elfcpp::STT_GNU_IFUNC
2850 && sym->is_from_dynobj())
2851 type = elfcpp::STT_FUNC;
2852 // A version script may have overridden the default binding.
2853 if (sym->is_forced_local())
2854 osym.put_st_info(elfcpp::elf_st_info(elfcpp::STB_LOCAL, type));
2856 osym.put_st_info(elfcpp::elf_st_info(binding, type));
2857 osym.put_st_other(elfcpp::elf_st_other(sym->visibility(), sym->nonvis()));
2858 osym.put_st_shndx(shndx);
2861 // Check for unresolved symbols in shared libraries. This is
2862 // controlled by the --allow-shlib-undefined option.
2864 // We only warn about libraries for which we have seen all the
2865 // DT_NEEDED entries. We don't try to track down DT_NEEDED entries
2866 // which were not seen in this link. If we didn't see a DT_NEEDED
2867 // entry, we aren't going to be able to reliably report whether the
2868 // symbol is undefined.
2870 // We also don't warn about libraries found in a system library
2871 // directory (e.g., /lib or /usr/lib); we assume that those libraries
2872 // are OK. This heuristic avoids problems on GNU/Linux, in which -ldl
2873 // can have undefined references satisfied by ld-linux.so.
2876 Symbol_table::warn_about_undefined_dynobj_symbol(Symbol* sym) const
2879 if (sym->source() == Symbol::FROM_OBJECT
2880 && sym->object()->is_dynamic()
2881 && sym->shndx(&dummy) == elfcpp::SHN_UNDEF
2882 && sym->binding() != elfcpp::STB_WEAK
2883 && !parameters->options().allow_shlib_undefined()
2884 && !parameters->target().is_defined_by_abi(sym)
2885 && !sym->object()->is_in_system_directory())
2887 // A very ugly cast.
2888 Dynobj* dynobj = static_cast<Dynobj*>(sym->object());
2889 if (!dynobj->has_unknown_needed_entries())
2890 gold_undefined_symbol(sym);
2894 // Write out a section symbol. Return the update offset.
2897 Symbol_table::write_section_symbol(const Output_section *os,
2898 Output_symtab_xindex* symtab_xindex,
2902 switch (parameters->size_and_endianness())
2904 #ifdef HAVE_TARGET_32_LITTLE
2905 case Parameters::TARGET_32_LITTLE:
2906 this->sized_write_section_symbol<32, false>(os, symtab_xindex, of,
2910 #ifdef HAVE_TARGET_32_BIG
2911 case Parameters::TARGET_32_BIG:
2912 this->sized_write_section_symbol<32, true>(os, symtab_xindex, of,
2916 #ifdef HAVE_TARGET_64_LITTLE
2917 case Parameters::TARGET_64_LITTLE:
2918 this->sized_write_section_symbol<64, false>(os, symtab_xindex, of,
2922 #ifdef HAVE_TARGET_64_BIG
2923 case Parameters::TARGET_64_BIG:
2924 this->sized_write_section_symbol<64, true>(os, symtab_xindex, of,
2933 // Write out a section symbol, specialized for size and endianness.
2935 template<int size, bool big_endian>
2937 Symbol_table::sized_write_section_symbol(const Output_section* os,
2938 Output_symtab_xindex* symtab_xindex,
2942 const int sym_size = elfcpp::Elf_sizes<size>::sym_size;
2944 unsigned char* pov = of->get_output_view(offset, sym_size);
2946 elfcpp::Sym_write<size, big_endian> osym(pov);
2947 osym.put_st_name(0);
2948 if (parameters->options().relocatable())
2949 osym.put_st_value(0);
2951 osym.put_st_value(os->address());
2952 osym.put_st_size(0);
2953 osym.put_st_info(elfcpp::elf_st_info(elfcpp::STB_LOCAL,
2954 elfcpp::STT_SECTION));
2955 osym.put_st_other(elfcpp::elf_st_other(elfcpp::STV_DEFAULT, 0));
2957 unsigned int shndx = os->out_shndx();
2958 if (shndx >= elfcpp::SHN_LORESERVE)
2960 symtab_xindex->add(os->symtab_index(), shndx);
2961 shndx = elfcpp::SHN_XINDEX;
2963 osym.put_st_shndx(shndx);
2965 of->write_output_view(offset, sym_size, pov);
2968 // Print statistical information to stderr. This is used for --stats.
2971 Symbol_table::print_stats() const
2973 #if defined(HAVE_TR1_UNORDERED_MAP) || defined(HAVE_EXT_HASH_MAP)
2974 fprintf(stderr, _("%s: symbol table entries: %zu; buckets: %zu\n"),
2975 program_name, this->table_.size(), this->table_.bucket_count());
2977 fprintf(stderr, _("%s: symbol table entries: %zu\n"),
2978 program_name, this->table_.size());
2980 this->namepool_.print_stats("symbol table stringpool");
2983 // We check for ODR violations by looking for symbols with the same
2984 // name for which the debugging information reports that they were
2985 // defined in different source locations. When comparing the source
2986 // location, we consider instances with the same base filename and
2987 // line number to be the same. This is because different object
2988 // files/shared libraries can include the same header file using
2989 // different paths, and we don't want to report an ODR violation in
2992 // This struct is used to compare line information, as returned by
2993 // Dwarf_line_info::one_addr2line. It implements a < comparison
2994 // operator used with std::set.
2996 struct Odr_violation_compare
2999 operator()(const std::string& s1, const std::string& s2) const
3001 std::string::size_type pos1 = s1.rfind('/');
3002 std::string::size_type pos2 = s2.rfind('/');
3003 if (pos1 == std::string::npos
3004 || pos2 == std::string::npos)
3006 return s1.compare(pos1, std::string::npos,
3007 s2, pos2, std::string::npos) < 0;
3011 // Check candidate_odr_violations_ to find symbols with the same name
3012 // but apparently different definitions (different source-file/line-no).
3015 Symbol_table::detect_odr_violations(const Task* task,
3016 const char* output_file_name) const
3018 for (Odr_map::const_iterator it = candidate_odr_violations_.begin();
3019 it != candidate_odr_violations_.end();
3022 const char* symbol_name = it->first;
3023 // Maps from symbol location to a sample object file we found
3024 // that location in. We use a sorted map so the location order
3025 // is deterministic, but we only store an arbitrary object file
3026 // to avoid copying lots of names.
3027 std::map<std::string, std::string, Odr_violation_compare> line_nums;
3029 for (Unordered_set<Symbol_location, Symbol_location_hash>::const_iterator
3030 locs = it->second.begin();
3031 locs != it->second.end();
3034 // We need to lock the object in order to read it. This
3035 // means that we have to run in a singleton Task. If we
3036 // want to run this in a general Task for better
3037 // performance, we will need one Task for object, plus
3038 // appropriate locking to ensure that we don't conflict with
3039 // other uses of the object. Also note, one_addr2line is not
3040 // currently thread-safe.
3041 Task_lock_obj<Object> tl(task, locs->object);
3042 // 16 is the size of the object-cache that one_addr2line should use.
3043 std::string lineno = Dwarf_line_info::one_addr2line(
3044 locs->object, locs->shndx, locs->offset, 16);
3045 if (!lineno.empty())
3047 std::string& sample_object = line_nums[lineno];
3048 if (sample_object.empty())
3049 sample_object = locs->object->name();
3053 if (line_nums.size() > 1)
3055 gold_warning(_("while linking %s: symbol '%s' defined in multiple "
3056 "places (possible ODR violation):"),
3057 output_file_name, demangle(symbol_name).c_str());
3058 for (std::map<std::string, std::string>::const_iterator it2 =
3060 it2 != line_nums.end();
3062 fprintf(stderr, _(" %s from %s\n"),
3063 it2->first.c_str(), it2->second.c_str());
3066 // We only call one_addr2line() in this function, so we can clear its cache.
3067 Dwarf_line_info::clear_addr2line_cache();
3070 // Warnings functions.
3072 // Add a new warning.
3075 Warnings::add_warning(Symbol_table* symtab, const char* name, Object* obj,
3076 const std::string& warning)
3078 name = symtab->canonicalize_name(name);
3079 this->warnings_[name].set(obj, warning);
3082 // Look through the warnings and mark the symbols for which we should
3083 // warn. This is called during Layout::finalize when we know the
3084 // sources for all the symbols.
3087 Warnings::note_warnings(Symbol_table* symtab)
3089 for (Warning_table::iterator p = this->warnings_.begin();
3090 p != this->warnings_.end();
3093 Symbol* sym = symtab->lookup(p->first, NULL);
3095 && sym->source() == Symbol::FROM_OBJECT
3096 && sym->object() == p->second.object)
3097 sym->set_has_warning();
3101 // Issue a warning. This is called when we see a relocation against a
3102 // symbol for which has a warning.
3104 template<int size, bool big_endian>
3106 Warnings::issue_warning(const Symbol* sym,
3107 const Relocate_info<size, big_endian>* relinfo,
3108 size_t relnum, off_t reloffset) const
3110 gold_assert(sym->has_warning());
3111 Warning_table::const_iterator p = this->warnings_.find(sym->name());
3112 gold_assert(p != this->warnings_.end());
3113 gold_warning_at_location(relinfo, relnum, reloffset,
3114 "%s", p->second.text.c_str());
3117 // Instantiate the templates we need. We could use the configure
3118 // script to restrict this to only the ones needed for implemented
3121 #if defined(HAVE_TARGET_32_LITTLE) || defined(HAVE_TARGET_32_BIG)
3124 Sized_symbol<32>::allocate_common(Output_data*, Value_type);
3127 #if defined(HAVE_TARGET_64_LITTLE) || defined(HAVE_TARGET_64_BIG)
3130 Sized_symbol<64>::allocate_common(Output_data*, Value_type);
3133 #ifdef HAVE_TARGET_32_LITTLE
3136 Symbol_table::add_from_relobj<32, false>(
3137 Sized_relobj<32, false>* relobj,
3138 const unsigned char* syms,
3140 size_t symndx_offset,
3141 const char* sym_names,
3142 size_t sym_name_size,
3143 Sized_relobj<32, false>::Symbols* sympointers,
3147 #ifdef HAVE_TARGET_32_BIG
3150 Symbol_table::add_from_relobj<32, true>(
3151 Sized_relobj<32, true>* relobj,
3152 const unsigned char* syms,
3154 size_t symndx_offset,
3155 const char* sym_names,
3156 size_t sym_name_size,
3157 Sized_relobj<32, true>::Symbols* sympointers,
3161 #ifdef HAVE_TARGET_64_LITTLE
3164 Symbol_table::add_from_relobj<64, false>(
3165 Sized_relobj<64, false>* relobj,
3166 const unsigned char* syms,
3168 size_t symndx_offset,
3169 const char* sym_names,
3170 size_t sym_name_size,
3171 Sized_relobj<64, false>::Symbols* sympointers,
3175 #ifdef HAVE_TARGET_64_BIG
3178 Symbol_table::add_from_relobj<64, true>(
3179 Sized_relobj<64, true>* relobj,
3180 const unsigned char* syms,
3182 size_t symndx_offset,
3183 const char* sym_names,
3184 size_t sym_name_size,
3185 Sized_relobj<64, true>::Symbols* sympointers,
3189 #ifdef HAVE_TARGET_32_LITTLE
3192 Symbol_table::add_from_pluginobj<32, false>(
3193 Sized_pluginobj<32, false>* obj,
3196 elfcpp::Sym<32, false>* sym);
3199 #ifdef HAVE_TARGET_32_BIG
3202 Symbol_table::add_from_pluginobj<32, true>(
3203 Sized_pluginobj<32, true>* obj,
3206 elfcpp::Sym<32, true>* sym);
3209 #ifdef HAVE_TARGET_64_LITTLE
3212 Symbol_table::add_from_pluginobj<64, false>(
3213 Sized_pluginobj<64, false>* obj,
3216 elfcpp::Sym<64, false>* sym);
3219 #ifdef HAVE_TARGET_64_BIG
3222 Symbol_table::add_from_pluginobj<64, true>(
3223 Sized_pluginobj<64, true>* obj,
3226 elfcpp::Sym<64, true>* sym);
3229 #ifdef HAVE_TARGET_32_LITTLE
3232 Symbol_table::add_from_dynobj<32, false>(
3233 Sized_dynobj<32, false>* dynobj,
3234 const unsigned char* syms,
3236 const char* sym_names,
3237 size_t sym_name_size,
3238 const unsigned char* versym,
3240 const std::vector<const char*>* version_map,
3241 Sized_relobj<32, false>::Symbols* sympointers,
3245 #ifdef HAVE_TARGET_32_BIG
3248 Symbol_table::add_from_dynobj<32, true>(
3249 Sized_dynobj<32, true>* dynobj,
3250 const unsigned char* syms,
3252 const char* sym_names,
3253 size_t sym_name_size,
3254 const unsigned char* versym,
3256 const std::vector<const char*>* version_map,
3257 Sized_relobj<32, true>::Symbols* sympointers,
3261 #ifdef HAVE_TARGET_64_LITTLE
3264 Symbol_table::add_from_dynobj<64, false>(
3265 Sized_dynobj<64, false>* dynobj,
3266 const unsigned char* syms,
3268 const char* sym_names,
3269 size_t sym_name_size,
3270 const unsigned char* versym,
3272 const std::vector<const char*>* version_map,
3273 Sized_relobj<64, false>::Symbols* sympointers,
3277 #ifdef HAVE_TARGET_64_BIG
3280 Symbol_table::add_from_dynobj<64, true>(
3281 Sized_dynobj<64, true>* dynobj,
3282 const unsigned char* syms,
3284 const char* sym_names,
3285 size_t sym_name_size,
3286 const unsigned char* versym,
3288 const std::vector<const char*>* version_map,
3289 Sized_relobj<64, true>::Symbols* sympointers,
3293 #if defined(HAVE_TARGET_32_LITTLE) || defined(HAVE_TARGET_32_BIG)
3296 Symbol_table::define_with_copy_reloc<32>(
3297 Sized_symbol<32>* sym,
3299 elfcpp::Elf_types<32>::Elf_Addr value);
3302 #if defined(HAVE_TARGET_64_LITTLE) || defined(HAVE_TARGET_64_BIG)
3305 Symbol_table::define_with_copy_reloc<64>(
3306 Sized_symbol<64>* sym,
3308 elfcpp::Elf_types<64>::Elf_Addr value);
3311 #ifdef HAVE_TARGET_32_LITTLE
3314 Warnings::issue_warning<32, false>(const Symbol* sym,
3315 const Relocate_info<32, false>* relinfo,
3316 size_t relnum, off_t reloffset) const;
3319 #ifdef HAVE_TARGET_32_BIG
3322 Warnings::issue_warning<32, true>(const Symbol* sym,
3323 const Relocate_info<32, true>* relinfo,
3324 size_t relnum, off_t reloffset) const;
3327 #ifdef HAVE_TARGET_64_LITTLE
3330 Warnings::issue_warning<64, false>(const Symbol* sym,
3331 const Relocate_info<64, false>* relinfo,
3332 size_t relnum, off_t reloffset) const;
3335 #ifdef HAVE_TARGET_64_BIG
3338 Warnings::issue_warning<64, true>(const Symbol* sym,
3339 const Relocate_info<64, true>* relinfo,
3340 size_t relnum, off_t reloffset) const;
3343 } // End namespace gold.