1 // symtab.cc -- the gold symbol table
3 // Copyright 2006, 2007, 2008, 2009 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_ = 0;
64 this->binding_ = binding;
65 this->visibility_ = visibility;
66 this->nonvis_ = nonvis;
67 this->is_target_special_ = false;
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_plt_offset_ = false;
75 this->has_warning_ = false;
76 this->is_copied_from_dynobj_ = false;
77 this->is_forced_local_ = false;
78 this->is_ordinary_shndx_ = false;
79 this->in_real_elf_ = false;
82 // Return the demangled version of the symbol's name, but only
83 // if the --demangle flag was set.
86 demangle(const char* name)
88 if (!parameters->options().do_demangle())
91 // cplus_demangle allocates memory for the result it returns,
92 // and returns NULL if the name is already demangled.
93 char* demangled_name = cplus_demangle(name, DMGL_ANSI | DMGL_PARAMS);
94 if (demangled_name == NULL)
97 std::string retval(demangled_name);
103 Symbol::demangled_name() const
105 return demangle(this->name());
108 // Initialize the fields in the base class Symbol for SYM in OBJECT.
110 template<int size, bool big_endian>
112 Symbol::init_base_object(const char* name, const char* version, Object* object,
113 const elfcpp::Sym<size, big_endian>& sym,
114 unsigned int st_shndx, bool is_ordinary)
116 this->init_fields(name, version, sym.get_st_type(), sym.get_st_bind(),
117 sym.get_st_visibility(), sym.get_st_nonvis());
118 this->u_.from_object.object = object;
119 this->u_.from_object.shndx = st_shndx;
120 this->is_ordinary_shndx_ = is_ordinary;
121 this->source_ = FROM_OBJECT;
122 this->in_reg_ = !object->is_dynamic();
123 this->in_dyn_ = object->is_dynamic();
124 this->in_real_elf_ = object->pluginobj() == NULL;
127 // Initialize the fields in the base class Symbol for a symbol defined
128 // in an Output_data.
131 Symbol::init_base_output_data(const char* name, const char* version,
132 Output_data* od, elfcpp::STT type,
133 elfcpp::STB binding, elfcpp::STV visibility,
134 unsigned char nonvis, bool offset_is_from_end)
136 this->init_fields(name, version, type, binding, visibility, nonvis);
137 this->u_.in_output_data.output_data = od;
138 this->u_.in_output_data.offset_is_from_end = offset_is_from_end;
139 this->source_ = IN_OUTPUT_DATA;
140 this->in_reg_ = true;
141 this->in_real_elf_ = true;
144 // Initialize the fields in the base class Symbol for a symbol defined
145 // in an Output_segment.
148 Symbol::init_base_output_segment(const char* name, const char* version,
149 Output_segment* os, elfcpp::STT type,
150 elfcpp::STB binding, elfcpp::STV visibility,
151 unsigned char nonvis,
152 Segment_offset_base offset_base)
154 this->init_fields(name, version, type, binding, visibility, nonvis);
155 this->u_.in_output_segment.output_segment = os;
156 this->u_.in_output_segment.offset_base = offset_base;
157 this->source_ = IN_OUTPUT_SEGMENT;
158 this->in_reg_ = true;
159 this->in_real_elf_ = true;
162 // Initialize the fields in the base class Symbol for a symbol defined
166 Symbol::init_base_constant(const char* name, const char* version,
167 elfcpp::STT type, elfcpp::STB binding,
168 elfcpp::STV visibility, unsigned char nonvis)
170 this->init_fields(name, version, type, binding, visibility, nonvis);
171 this->source_ = IS_CONSTANT;
172 this->in_reg_ = true;
173 this->in_real_elf_ = true;
176 // Initialize the fields in the base class Symbol for an undefined
180 Symbol::init_base_undefined(const char* name, const char* version,
181 elfcpp::STT type, elfcpp::STB binding,
182 elfcpp::STV visibility, unsigned char nonvis)
184 this->init_fields(name, version, type, binding, visibility, nonvis);
185 this->dynsym_index_ = -1U;
186 this->source_ = IS_UNDEFINED;
187 this->in_reg_ = true;
188 this->in_real_elf_ = true;
191 // Allocate a common symbol in the base.
194 Symbol::allocate_base_common(Output_data* od)
196 gold_assert(this->is_common());
197 this->source_ = IN_OUTPUT_DATA;
198 this->u_.in_output_data.output_data = od;
199 this->u_.in_output_data.offset_is_from_end = false;
202 // Initialize the fields in Sized_symbol for SYM in OBJECT.
205 template<bool big_endian>
207 Sized_symbol<size>::init_object(const char* name, const char* version,
209 const elfcpp::Sym<size, big_endian>& sym,
210 unsigned int st_shndx, bool is_ordinary)
212 this->init_base_object(name, version, object, sym, st_shndx, is_ordinary);
213 this->value_ = sym.get_st_value();
214 this->symsize_ = sym.get_st_size();
217 // Initialize the fields in Sized_symbol for a symbol defined in an
222 Sized_symbol<size>::init_output_data(const char* name, const char* version,
223 Output_data* od, Value_type value,
224 Size_type symsize, elfcpp::STT type,
226 elfcpp::STV visibility,
227 unsigned char nonvis,
228 bool offset_is_from_end)
230 this->init_base_output_data(name, version, od, type, binding, visibility,
231 nonvis, offset_is_from_end);
232 this->value_ = value;
233 this->symsize_ = symsize;
236 // Initialize the fields in Sized_symbol for a symbol defined in an
241 Sized_symbol<size>::init_output_segment(const char* name, const char* version,
242 Output_segment* os, Value_type value,
243 Size_type symsize, elfcpp::STT type,
245 elfcpp::STV visibility,
246 unsigned char nonvis,
247 Segment_offset_base offset_base)
249 this->init_base_output_segment(name, version, os, type, binding, visibility,
250 nonvis, offset_base);
251 this->value_ = value;
252 this->symsize_ = symsize;
255 // Initialize the fields in Sized_symbol for a symbol defined as a
260 Sized_symbol<size>::init_constant(const char* name, const char* version,
261 Value_type value, Size_type symsize,
262 elfcpp::STT type, elfcpp::STB binding,
263 elfcpp::STV visibility, unsigned char nonvis)
265 this->init_base_constant(name, version, type, binding, visibility, nonvis);
266 this->value_ = value;
267 this->symsize_ = symsize;
270 // Initialize the fields in Sized_symbol for an undefined symbol.
274 Sized_symbol<size>::init_undefined(const char* name, const char* version,
275 elfcpp::STT type, elfcpp::STB binding,
276 elfcpp::STV visibility, unsigned char nonvis)
278 this->init_base_undefined(name, version, type, binding, visibility, nonvis);
283 // Allocate a common symbol.
287 Sized_symbol<size>::allocate_common(Output_data* od, Value_type value)
289 this->allocate_base_common(od);
290 this->value_ = value;
293 // The ""'s around str ensure str is a string literal, so sizeof works.
294 #define strprefix(var, str) (strncmp(var, str, sizeof("" str "") - 1) == 0)
296 // Return true if this symbol should be added to the dynamic symbol
300 Symbol::should_add_dynsym_entry() const
302 // If the symbol is used by a dynamic relocation, we need to add it.
303 if (this->needs_dynsym_entry())
306 // If this symbol's section is not added, the symbol need not be added.
307 // The section may have been GCed. Note that export_dynamic is being
308 // overridden here. This should not be done for shared objects.
309 if (parameters->options().gc_sections()
310 && !parameters->options().shared()
311 && this->source() == Symbol::FROM_OBJECT
312 && !this->object()->is_dynamic())
314 Relobj* relobj = static_cast<Relobj*>(this->object());
316 unsigned int shndx = this->shndx(&is_ordinary);
317 if (is_ordinary && shndx != elfcpp::SHN_UNDEF
318 && !relobj->is_section_included(shndx))
322 // If the symbol was forced local in a version script, do not add it.
323 if (this->is_forced_local())
326 // If the symbol was forced dynamic in a --dynamic-list file, add it.
327 if (parameters->options().in_dynamic_list(this->name()))
330 // If dynamic-list-data was specified, add any STT_OBJECT.
331 if (parameters->options().dynamic_list_data()
332 && !this->is_from_dynobj()
333 && this->type() == elfcpp::STT_OBJECT)
336 // If --dynamic-list-cpp-new was specified, add any new/delete symbol.
337 // If --dynamic-list-cpp-typeinfo was specified, add any typeinfo symbols.
338 if ((parameters->options().dynamic_list_cpp_new()
339 || parameters->options().dynamic_list_cpp_typeinfo())
340 && !this->is_from_dynobj())
342 // TODO(csilvers): We could probably figure out if we're an operator
343 // new/delete or typeinfo without the need to demangle.
344 char* demangled_name = cplus_demangle(this->name(),
345 DMGL_ANSI | DMGL_PARAMS);
346 if (demangled_name == NULL)
348 // Not a C++ symbol, so it can't satisfy these flags
350 else if (parameters->options().dynamic_list_cpp_new()
351 && (strprefix(demangled_name, "operator new")
352 || strprefix(demangled_name, "operator delete")))
354 free(demangled_name);
357 else if (parameters->options().dynamic_list_cpp_typeinfo()
358 && (strprefix(demangled_name, "typeinfo name for")
359 || strprefix(demangled_name, "typeinfo for")))
361 free(demangled_name);
365 free(demangled_name);
368 // If exporting all symbols or building a shared library,
369 // and the symbol is defined in a regular object and is
370 // externally visible, we need to add it.
371 if ((parameters->options().export_dynamic() || parameters->options().shared())
372 && !this->is_from_dynobj()
373 && this->is_externally_visible())
379 // Return true if the final value of this symbol is known at link
383 Symbol::final_value_is_known() const
385 // If we are not generating an executable, then no final values are
386 // known, since they will change at runtime.
387 if (parameters->options().shared() || parameters->options().relocatable())
390 // If the symbol is not from an object file, and is not undefined,
391 // then it is defined, and known.
392 if (this->source_ != FROM_OBJECT)
394 if (this->source_ != IS_UNDEFINED)
399 // If the symbol is from a dynamic object, then the final value
401 if (this->object()->is_dynamic())
404 // If the symbol is not undefined (it is defined or common),
405 // then the final value is known.
406 if (!this->is_undefined())
410 // If the symbol is undefined, then whether the final value is known
411 // depends on whether we are doing a static link. If we are doing a
412 // dynamic link, then the final value could be filled in at runtime.
413 // This could reasonably be the case for a weak undefined symbol.
414 return parameters->doing_static_link();
417 // Return the output section where this symbol is defined.
420 Symbol::output_section() const
422 switch (this->source_)
426 unsigned int shndx = this->u_.from_object.shndx;
427 if (shndx != elfcpp::SHN_UNDEF && this->is_ordinary_shndx_)
429 gold_assert(!this->u_.from_object.object->is_dynamic());
430 gold_assert(this->u_.from_object.object->pluginobj() == NULL);
431 Relobj* relobj = static_cast<Relobj*>(this->u_.from_object.object);
432 return relobj->output_section(shndx);
438 return this->u_.in_output_data.output_data->output_section();
440 case IN_OUTPUT_SEGMENT:
450 // Set the symbol's output section. This is used for symbols defined
451 // in scripts. This should only be called after the symbol table has
455 Symbol::set_output_section(Output_section* os)
457 switch (this->source_)
461 gold_assert(this->output_section() == os);
464 this->source_ = IN_OUTPUT_DATA;
465 this->u_.in_output_data.output_data = os;
466 this->u_.in_output_data.offset_is_from_end = false;
468 case IN_OUTPUT_SEGMENT:
475 // Class Symbol_table.
477 Symbol_table::Symbol_table(unsigned int count,
478 const Version_script_info& version_script)
479 : saw_undefined_(0), offset_(0), table_(count), namepool_(),
480 forwarders_(), commons_(), tls_commons_(), forced_locals_(), warnings_(),
481 version_script_(version_script), gc_(NULL)
483 namepool_.reserve(count);
486 Symbol_table::~Symbol_table()
490 // The hash function. The key values are Stringpool keys.
493 Symbol_table::Symbol_table_hash::operator()(const Symbol_table_key& key) const
495 return key.first ^ key.second;
498 // The symbol table key equality function. This is called with
502 Symbol_table::Symbol_table_eq::operator()(const Symbol_table_key& k1,
503 const Symbol_table_key& k2) const
505 return k1.first == k2.first && k1.second == k2.second;
508 // For symbols that have been listed with -u option, add them to the
509 // work list to avoid gc'ing them.
512 Symbol_table::gc_mark_undef_symbols()
514 for (options::String_set::const_iterator p =
515 parameters->options().undefined_begin();
516 p != parameters->options().undefined_end();
519 const char* name = p->c_str();
520 Symbol* sym = this->lookup(name);
521 gold_assert (sym != NULL);
522 if (sym->source() == Symbol::FROM_OBJECT
523 && !sym->object()->is_dynamic())
525 Relobj* obj = static_cast<Relobj*>(sym->object());
527 unsigned int shndx = sym->shndx(&is_ordinary);
530 gold_assert(this->gc_ != NULL);
531 this->gc_->worklist().push(Section_id(obj, shndx));
538 Symbol_table::gc_mark_symbol_for_shlib(Symbol* sym)
540 if (!sym->is_from_dynobj()
541 && sym->is_externally_visible())
543 //Add the object and section to the work list.
544 Relobj* obj = static_cast<Relobj*>(sym->object());
546 unsigned int shndx = sym->shndx(&is_ordinary);
547 if (is_ordinary && shndx != elfcpp::SHN_UNDEF)
549 gold_assert(this->gc_!= NULL);
550 this->gc_->worklist().push(Section_id(obj, shndx));
555 // When doing garbage collection, keep symbols that have been seen in
558 Symbol_table::gc_mark_dyn_syms(Symbol* sym)
560 if (sym->in_dyn() && sym->source() == Symbol::FROM_OBJECT
561 && !sym->object()->is_dynamic())
563 Relobj *obj = static_cast<Relobj*>(sym->object());
565 unsigned int shndx = sym->shndx(&is_ordinary);
566 if (is_ordinary && shndx != elfcpp::SHN_UNDEF)
568 gold_assert(this->gc_ != NULL);
569 this->gc_->worklist().push(Section_id(obj, shndx));
574 // Make TO a symbol which forwards to FROM.
577 Symbol_table::make_forwarder(Symbol* from, Symbol* to)
579 gold_assert(from != to);
580 gold_assert(!from->is_forwarder() && !to->is_forwarder());
581 this->forwarders_[from] = to;
582 from->set_forwarder();
585 // Resolve the forwards from FROM, returning the real symbol.
588 Symbol_table::resolve_forwards(const Symbol* from) const
590 gold_assert(from->is_forwarder());
591 Unordered_map<const Symbol*, Symbol*>::const_iterator p =
592 this->forwarders_.find(from);
593 gold_assert(p != this->forwarders_.end());
597 // Look up a symbol by name.
600 Symbol_table::lookup(const char* name, const char* version) const
602 Stringpool::Key name_key;
603 name = this->namepool_.find(name, &name_key);
607 Stringpool::Key version_key = 0;
610 version = this->namepool_.find(version, &version_key);
615 Symbol_table_key key(name_key, version_key);
616 Symbol_table::Symbol_table_type::const_iterator p = this->table_.find(key);
617 if (p == this->table_.end())
622 // Resolve a Symbol with another Symbol. This is only used in the
623 // unusual case where there are references to both an unversioned
624 // symbol and a symbol with a version, and we then discover that that
625 // version is the default version. Because this is unusual, we do
626 // this the slow way, by converting back to an ELF symbol.
628 template<int size, bool big_endian>
630 Symbol_table::resolve(Sized_symbol<size>* to, const Sized_symbol<size>* from)
632 unsigned char buf[elfcpp::Elf_sizes<size>::sym_size];
633 elfcpp::Sym_write<size, big_endian> esym(buf);
634 // We don't bother to set the st_name or the st_shndx field.
635 esym.put_st_value(from->value());
636 esym.put_st_size(from->symsize());
637 esym.put_st_info(from->binding(), from->type());
638 esym.put_st_other(from->visibility(), from->nonvis());
640 unsigned int shndx = from->shndx(&is_ordinary);
641 this->resolve(to, esym.sym(), shndx, is_ordinary, shndx, from->object(),
647 if (parameters->options().gc_sections())
648 this->gc_mark_dyn_syms(to);
651 // Record that a symbol is forced to be local by a version script.
654 Symbol_table::force_local(Symbol* sym)
656 if (!sym->is_defined() && !sym->is_common())
658 if (sym->is_forced_local())
660 // We already got this one.
663 sym->set_is_forced_local();
664 this->forced_locals_.push_back(sym);
667 // Adjust NAME for wrapping, and update *NAME_KEY if necessary. This
668 // is only called for undefined symbols, when at least one --wrap
672 Symbol_table::wrap_symbol(Object* object, const char* name,
673 Stringpool::Key* name_key)
675 // For some targets, we need to ignore a specific character when
676 // wrapping, and add it back later.
678 if (name[0] == object->target()->wrap_char())
684 if (parameters->options().is_wrap(name))
686 // Turn NAME into __wrap_NAME.
693 // This will give us both the old and new name in NAMEPOOL_, but
694 // that is OK. Only the versions we need will wind up in the
695 // real string table in the output file.
696 return this->namepool_.add(s.c_str(), true, name_key);
699 const char* const real_prefix = "__real_";
700 const size_t real_prefix_length = strlen(real_prefix);
701 if (strncmp(name, real_prefix, real_prefix_length) == 0
702 && parameters->options().is_wrap(name + real_prefix_length))
704 // Turn __real_NAME into NAME.
708 s += name + real_prefix_length;
709 return this->namepool_.add(s.c_str(), true, name_key);
715 // Add one symbol from OBJECT to the symbol table. NAME is symbol
716 // name and VERSION is the version; both are canonicalized. DEF is
717 // whether this is the default version. ST_SHNDX is the symbol's
718 // section index; IS_ORDINARY is whether this is a normal section
719 // rather than a special code.
721 // If DEF is true, then this is the definition of a default version of
722 // a symbol. That means that any lookup of NAME/NULL and any lookup
723 // of NAME/VERSION should always return the same symbol. This is
724 // obvious for references, but in particular we want to do this for
725 // definitions: overriding NAME/NULL should also override
726 // NAME/VERSION. If we don't do that, it would be very hard to
727 // override functions in a shared library which uses versioning.
729 // We implement this by simply making both entries in the hash table
730 // point to the same Symbol structure. That is easy enough if this is
731 // the first time we see NAME/NULL or NAME/VERSION, but it is possible
732 // that we have seen both already, in which case they will both have
733 // independent entries in the symbol table. We can't simply change
734 // the symbol table entry, because we have pointers to the entries
735 // attached to the object files. So we mark the entry attached to the
736 // object file as a forwarder, and record it in the forwarders_ map.
737 // Note that entries in the hash table will never be marked as
740 // ORIG_ST_SHNDX and ST_SHNDX are almost always the same.
741 // ORIG_ST_SHNDX is the section index in the input file, or SHN_UNDEF
742 // for a special section code. ST_SHNDX may be modified if the symbol
743 // is defined in a section being discarded.
745 template<int size, bool big_endian>
747 Symbol_table::add_from_object(Object* object,
749 Stringpool::Key name_key,
751 Stringpool::Key version_key,
753 const elfcpp::Sym<size, big_endian>& sym,
754 unsigned int st_shndx,
756 unsigned int orig_st_shndx)
758 // Print a message if this symbol is being traced.
759 if (parameters->options().is_trace_symbol(name))
761 if (orig_st_shndx == elfcpp::SHN_UNDEF)
762 gold_info(_("%s: reference to %s"), object->name().c_str(), name);
764 gold_info(_("%s: definition of %s"), object->name().c_str(), name);
767 // For an undefined symbol, we may need to adjust the name using
769 if (orig_st_shndx == elfcpp::SHN_UNDEF
770 && parameters->options().any_wrap())
772 const char* wrap_name = this->wrap_symbol(object, name, &name_key);
773 if (wrap_name != name)
775 // If we see a reference to malloc with version GLIBC_2.0,
776 // and we turn it into a reference to __wrap_malloc, then we
777 // discard the version number. Otherwise the user would be
778 // required to specify the correct version for
786 Symbol* const snull = NULL;
787 std::pair<typename Symbol_table_type::iterator, bool> ins =
788 this->table_.insert(std::make_pair(std::make_pair(name_key, version_key),
791 std::pair<typename Symbol_table_type::iterator, bool> insdef =
792 std::make_pair(this->table_.end(), false);
795 const Stringpool::Key vnull_key = 0;
796 insdef = this->table_.insert(std::make_pair(std::make_pair(name_key,
801 // ins.first: an iterator, which is a pointer to a pair.
802 // ins.first->first: the key (a pair of name and version).
803 // ins.first->second: the value (Symbol*).
804 // ins.second: true if new entry was inserted, false if not.
806 Sized_symbol<size>* ret;
811 // We already have an entry for NAME/VERSION.
812 ret = this->get_sized_symbol<size>(ins.first->second);
813 gold_assert(ret != NULL);
815 was_undefined = ret->is_undefined();
816 was_common = ret->is_common();
818 this->resolve(ret, sym, st_shndx, is_ordinary, orig_st_shndx, object,
820 if (parameters->options().gc_sections())
821 this->gc_mark_dyn_syms(ret);
827 // This is the first time we have seen NAME/NULL. Make
828 // NAME/NULL point to NAME/VERSION.
829 insdef.first->second = ret;
831 else if (insdef.first->second != ret)
833 // This is the unfortunate case where we already have
834 // entries for both NAME/VERSION and NAME/NULL. We now
835 // see a symbol NAME/VERSION where VERSION is the
836 // default version. We have already resolved this new
837 // symbol with the existing NAME/VERSION symbol.
839 // It's possible that NAME/NULL and NAME/VERSION are
840 // both defined in regular objects. This can only
841 // happen if one object file defines foo and another
842 // defines foo@@ver. This is somewhat obscure, but we
843 // call it a multiple definition error.
845 // It's possible that NAME/NULL actually has a version,
846 // in which case it won't be the same as VERSION. This
847 // happens with ver_test_7.so in the testsuite for the
848 // symbol t2_2. We see t2_2@@VER2, so we define both
849 // t2_2/VER2 and t2_2/NULL. We then see an unadorned
850 // t2_2 in an object file and give it version VER1 from
851 // the version script. This looks like a default
852 // definition for VER1, so it looks like we should merge
853 // t2_2/NULL with t2_2/VER1. That doesn't make sense,
854 // but it's not obvious that this is an error, either.
857 // If one of the symbols has non-default visibility, and
858 // the other is defined in a shared object, then they
859 // are different symbols.
861 // Otherwise, we just resolve the symbols as though they
864 if (insdef.first->second->version() != NULL)
866 gold_assert(insdef.first->second->version() != version);
869 else if (ret->visibility() != elfcpp::STV_DEFAULT
870 && insdef.first->second->is_from_dynobj())
872 else if (insdef.first->second->visibility() != elfcpp::STV_DEFAULT
873 && ret->is_from_dynobj())
877 const Sized_symbol<size>* sym2;
878 sym2 = this->get_sized_symbol<size>(insdef.first->second);
879 Symbol_table::resolve<size, big_endian>(ret, sym2);
880 this->make_forwarder(insdef.first->second, ret);
881 insdef.first->second = ret;
890 // This is the first time we have seen NAME/VERSION.
891 gold_assert(ins.first->second == NULL);
893 if (def && !insdef.second)
895 // We already have an entry for NAME/NULL. If we override
896 // it, then change it to NAME/VERSION.
897 ret = this->get_sized_symbol<size>(insdef.first->second);
899 was_undefined = ret->is_undefined();
900 was_common = ret->is_common();
902 this->resolve(ret, sym, st_shndx, is_ordinary, orig_st_shndx, object,
904 if (parameters->options().gc_sections())
905 this->gc_mark_dyn_syms(ret);
906 ins.first->second = ret;
910 was_undefined = false;
913 Sized_target<size, big_endian>* target =
914 object->sized_target<size, big_endian>();
915 if (!target->has_make_symbol())
916 ret = new Sized_symbol<size>();
919 ret = target->make_symbol();
922 // This means that we don't want a symbol table
925 this->table_.erase(ins.first);
928 this->table_.erase(insdef.first);
929 // Inserting insdef invalidated ins.
930 this->table_.erase(std::make_pair(name_key,
937 ret->init_object(name, version, object, sym, st_shndx, is_ordinary);
939 ins.first->second = ret;
942 // This is the first time we have seen NAME/NULL. Point
943 // it at the new entry for NAME/VERSION.
944 gold_assert(insdef.second);
945 insdef.first->second = ret;
950 // Record every time we see a new undefined symbol, to speed up
952 if (!was_undefined && ret->is_undefined())
953 ++this->saw_undefined_;
955 // Keep track of common symbols, to speed up common symbol
957 if (!was_common && ret->is_common())
959 if (ret->type() != elfcpp::STT_TLS)
960 this->commons_.push_back(ret);
962 this->tls_commons_.push_back(ret);
966 ret->set_is_default();
970 // Add all the symbols in a relocatable object to the hash table.
972 template<int size, bool big_endian>
974 Symbol_table::add_from_relobj(
975 Sized_relobj<size, big_endian>* relobj,
976 const unsigned char* syms,
978 size_t symndx_offset,
979 const char* sym_names,
980 size_t sym_name_size,
981 typename Sized_relobj<size, big_endian>::Symbols* sympointers,
986 gold_assert(size == relobj->target()->get_size());
987 gold_assert(size == parameters->target().get_size());
989 const int sym_size = elfcpp::Elf_sizes<size>::sym_size;
991 const bool just_symbols = relobj->just_symbols();
993 const unsigned char* p = syms;
994 for (size_t i = 0; i < count; ++i, p += sym_size)
996 (*sympointers)[i] = NULL;
998 elfcpp::Sym<size, big_endian> sym(p);
1000 unsigned int st_name = sym.get_st_name();
1001 if (st_name >= sym_name_size)
1003 relobj->error(_("bad global symbol name offset %u at %zu"),
1008 const char* name = sym_names + st_name;
1011 unsigned int st_shndx = relobj->adjust_sym_shndx(i + symndx_offset,
1014 unsigned int orig_st_shndx = st_shndx;
1016 orig_st_shndx = elfcpp::SHN_UNDEF;
1018 if (st_shndx != elfcpp::SHN_UNDEF)
1021 // A symbol defined in a section which we are not including must
1022 // be treated as an undefined symbol.
1023 if (st_shndx != elfcpp::SHN_UNDEF
1025 && !relobj->is_section_included(st_shndx))
1026 st_shndx = elfcpp::SHN_UNDEF;
1028 // In an object file, an '@' in the name separates the symbol
1029 // name from the version name. If there are two '@' characters,
1030 // this is the default version.
1031 const char* ver = strchr(name, '@');
1032 Stringpool::Key ver_key = 0;
1034 // DEF: is the version default? LOCAL: is the symbol forced local?
1040 // The symbol name is of the form foo@VERSION or foo@@VERSION
1041 namelen = ver - name;
1048 ver = this->namepool_.add(ver, true, &ver_key);
1050 // We don't want to assign a version to an undefined symbol,
1051 // even if it is listed in the version script. FIXME: What
1052 // about a common symbol?
1055 namelen = strlen(name);
1056 if (!this->version_script_.empty()
1057 && st_shndx != elfcpp::SHN_UNDEF)
1059 // The symbol name did not have a version, but the
1060 // version script may assign a version anyway.
1061 std::string version;
1062 if (this->version_script_.get_symbol_version(name, &version))
1064 // The version can be empty if the version script is
1065 // only used to force some symbols to be local.
1066 if (!version.empty())
1068 ver = this->namepool_.add_with_length(version.c_str(),
1075 else if (this->version_script_.symbol_is_local(name))
1080 elfcpp::Sym<size, big_endian>* psym = &sym;
1081 unsigned char symbuf[sym_size];
1082 elfcpp::Sym<size, big_endian> sym2(symbuf);
1085 memcpy(symbuf, p, sym_size);
1086 elfcpp::Sym_write<size, big_endian> sw(symbuf);
1087 if (orig_st_shndx != elfcpp::SHN_UNDEF && is_ordinary)
1089 // Symbol values in object files are section relative.
1090 // This is normally what we want, but since here we are
1091 // converting the symbol to absolute we need to add the
1092 // section address. The section address in an object
1093 // file is normally zero, but people can use a linker
1094 // script to change it.
1095 sw.put_st_value(sym.get_st_value()
1096 + relobj->section_address(orig_st_shndx));
1098 st_shndx = elfcpp::SHN_ABS;
1099 is_ordinary = false;
1103 Stringpool::Key name_key;
1104 name = this->namepool_.add_with_length(name, namelen, true,
1107 Sized_symbol<size>* res;
1108 res = this->add_from_object(relobj, name, name_key, ver, ver_key,
1109 def, *psym, st_shndx, is_ordinary,
1112 // If building a shared library using garbage collection, do not
1113 // treat externally visible symbols as garbage.
1114 if (parameters->options().gc_sections()
1115 && parameters->options().shared())
1116 this->gc_mark_symbol_for_shlib(res);
1119 this->force_local(res);
1121 (*sympointers)[i] = res;
1125 // Add a symbol from a plugin-claimed file.
1127 template<int size, bool big_endian>
1129 Symbol_table::add_from_pluginobj(
1130 Sized_pluginobj<size, big_endian>* obj,
1133 elfcpp::Sym<size, big_endian>* sym)
1135 unsigned int st_shndx = sym->get_st_shndx();
1137 Stringpool::Key ver_key = 0;
1143 ver = this->namepool_.add(ver, true, &ver_key);
1145 // We don't want to assign a version to an undefined symbol,
1146 // even if it is listed in the version script. FIXME: What
1147 // about a common symbol?
1150 if (!this->version_script_.empty()
1151 && st_shndx != elfcpp::SHN_UNDEF)
1153 // The symbol name did not have a version, but the
1154 // version script may assign a version anyway.
1155 std::string version;
1156 if (this->version_script_.get_symbol_version(name, &version))
1158 // The version can be empty if the version script is
1159 // only used to force some symbols to be local.
1160 if (!version.empty())
1162 ver = this->namepool_.add_with_length(version.c_str(),
1169 else if (this->version_script_.symbol_is_local(name))
1174 Stringpool::Key name_key;
1175 name = this->namepool_.add(name, true, &name_key);
1177 Sized_symbol<size>* res;
1178 res = this->add_from_object(obj, name, name_key, ver, ver_key,
1179 def, *sym, st_shndx, true, st_shndx);
1182 this->force_local(res);
1187 // Add all the symbols in a dynamic object to the hash table.
1189 template<int size, bool big_endian>
1191 Symbol_table::add_from_dynobj(
1192 Sized_dynobj<size, big_endian>* dynobj,
1193 const unsigned char* syms,
1195 const char* sym_names,
1196 size_t sym_name_size,
1197 const unsigned char* versym,
1199 const std::vector<const char*>* version_map,
1200 typename Sized_relobj<size, big_endian>::Symbols* sympointers,
1205 gold_assert(size == dynobj->target()->get_size());
1206 gold_assert(size == parameters->target().get_size());
1208 if (dynobj->just_symbols())
1210 gold_error(_("--just-symbols does not make sense with a shared object"));
1214 if (versym != NULL && versym_size / 2 < count)
1216 dynobj->error(_("too few symbol versions"));
1220 const int sym_size = elfcpp::Elf_sizes<size>::sym_size;
1222 // We keep a list of all STT_OBJECT symbols, so that we can resolve
1223 // weak aliases. This is necessary because if the dynamic object
1224 // provides the same variable under two names, one of which is a
1225 // weak definition, and the regular object refers to the weak
1226 // definition, we have to put both the weak definition and the
1227 // strong definition into the dynamic symbol table. Given a weak
1228 // definition, the only way that we can find the corresponding
1229 // strong definition, if any, is to search the symbol table.
1230 std::vector<Sized_symbol<size>*> object_symbols;
1232 const unsigned char* p = syms;
1233 const unsigned char* vs = versym;
1234 for (size_t i = 0; i < count; ++i, p += sym_size, vs += 2)
1236 elfcpp::Sym<size, big_endian> sym(p);
1238 if (sympointers != NULL)
1239 (*sympointers)[i] = NULL;
1241 // Ignore symbols with local binding or that have
1242 // internal or hidden visibility.
1243 if (sym.get_st_bind() == elfcpp::STB_LOCAL
1244 || sym.get_st_visibility() == elfcpp::STV_INTERNAL
1245 || sym.get_st_visibility() == elfcpp::STV_HIDDEN)
1248 // A protected symbol in a shared library must be treated as a
1249 // normal symbol when viewed from outside the shared library.
1250 // Implement this by overriding the visibility here.
1251 elfcpp::Sym<size, big_endian>* psym = &sym;
1252 unsigned char symbuf[sym_size];
1253 elfcpp::Sym<size, big_endian> sym2(symbuf);
1254 if (sym.get_st_visibility() == elfcpp::STV_PROTECTED)
1256 memcpy(symbuf, p, sym_size);
1257 elfcpp::Sym_write<size, big_endian> sw(symbuf);
1258 sw.put_st_other(elfcpp::STV_DEFAULT, sym.get_st_nonvis());
1262 unsigned int st_name = psym->get_st_name();
1263 if (st_name >= sym_name_size)
1265 dynobj->error(_("bad symbol name offset %u at %zu"),
1270 const char* name = sym_names + st_name;
1273 unsigned int st_shndx = dynobj->adjust_sym_shndx(i, psym->get_st_shndx(),
1276 if (st_shndx != elfcpp::SHN_UNDEF)
1279 Sized_symbol<size>* res;
1283 Stringpool::Key name_key;
1284 name = this->namepool_.add(name, true, &name_key);
1285 res = this->add_from_object(dynobj, name, name_key, NULL, 0,
1286 false, *psym, st_shndx, is_ordinary,
1291 // Read the version information.
1293 unsigned int v = elfcpp::Swap<16, big_endian>::readval(vs);
1295 bool hidden = (v & elfcpp::VERSYM_HIDDEN) != 0;
1296 v &= elfcpp::VERSYM_VERSION;
1298 // The Sun documentation says that V can be VER_NDX_LOCAL,
1299 // or VER_NDX_GLOBAL, or a version index. The meaning of
1300 // VER_NDX_LOCAL is defined as "Symbol has local scope."
1301 // The old GNU linker will happily generate VER_NDX_LOCAL
1302 // for an undefined symbol. I don't know what the Sun
1303 // linker will generate.
1305 if (v == static_cast<unsigned int>(elfcpp::VER_NDX_LOCAL)
1306 && st_shndx != elfcpp::SHN_UNDEF)
1308 // This symbol should not be visible outside the object.
1312 // At this point we are definitely going to add this symbol.
1313 Stringpool::Key name_key;
1314 name = this->namepool_.add(name, true, &name_key);
1316 if (v == static_cast<unsigned int>(elfcpp::VER_NDX_LOCAL)
1317 || v == static_cast<unsigned int>(elfcpp::VER_NDX_GLOBAL))
1319 // This symbol does not have a version.
1320 res = this->add_from_object(dynobj, name, name_key, NULL, 0,
1321 false, *psym, st_shndx, is_ordinary,
1326 if (v >= version_map->size())
1328 dynobj->error(_("versym for symbol %zu out of range: %u"),
1333 const char* version = (*version_map)[v];
1334 if (version == NULL)
1336 dynobj->error(_("versym for symbol %zu has no name: %u"),
1341 Stringpool::Key version_key;
1342 version = this->namepool_.add(version, true, &version_key);
1344 // If this is an absolute symbol, and the version name
1345 // and symbol name are the same, then this is the
1346 // version definition symbol. These symbols exist to
1347 // support using -u to pull in particular versions. We
1348 // do not want to record a version for them.
1349 if (st_shndx == elfcpp::SHN_ABS
1351 && name_key == version_key)
1352 res = this->add_from_object(dynobj, name, name_key, NULL, 0,
1353 false, *psym, st_shndx, is_ordinary,
1357 const bool def = (!hidden
1358 && st_shndx != elfcpp::SHN_UNDEF);
1359 res = this->add_from_object(dynobj, name, name_key, version,
1360 version_key, def, *psym, st_shndx,
1361 is_ordinary, st_shndx);
1366 // Note that it is possible that RES was overridden by an
1367 // earlier object, in which case it can't be aliased here.
1368 if (st_shndx != elfcpp::SHN_UNDEF
1370 && psym->get_st_type() == elfcpp::STT_OBJECT
1371 && res->source() == Symbol::FROM_OBJECT
1372 && res->object() == dynobj)
1373 object_symbols.push_back(res);
1375 if (sympointers != NULL)
1376 (*sympointers)[i] = res;
1379 this->record_weak_aliases(&object_symbols);
1382 // This is used to sort weak aliases. We sort them first by section
1383 // index, then by offset, then by weak ahead of strong.
1386 class Weak_alias_sorter
1389 bool operator()(const Sized_symbol<size>*, const Sized_symbol<size>*) const;
1394 Weak_alias_sorter<size>::operator()(const Sized_symbol<size>* s1,
1395 const Sized_symbol<size>* s2) const
1398 unsigned int s1_shndx = s1->shndx(&is_ordinary);
1399 gold_assert(is_ordinary);
1400 unsigned int s2_shndx = s2->shndx(&is_ordinary);
1401 gold_assert(is_ordinary);
1402 if (s1_shndx != s2_shndx)
1403 return s1_shndx < s2_shndx;
1405 if (s1->value() != s2->value())
1406 return s1->value() < s2->value();
1407 if (s1->binding() != s2->binding())
1409 if (s1->binding() == elfcpp::STB_WEAK)
1411 if (s2->binding() == elfcpp::STB_WEAK)
1414 return std::string(s1->name()) < std::string(s2->name());
1417 // SYMBOLS is a list of object symbols from a dynamic object. Look
1418 // for any weak aliases, and record them so that if we add the weak
1419 // alias to the dynamic symbol table, we also add the corresponding
1424 Symbol_table::record_weak_aliases(std::vector<Sized_symbol<size>*>* symbols)
1426 // Sort the vector by section index, then by offset, then by weak
1428 std::sort(symbols->begin(), symbols->end(), Weak_alias_sorter<size>());
1430 // Walk through the vector. For each weak definition, record
1432 for (typename std::vector<Sized_symbol<size>*>::const_iterator p =
1434 p != symbols->end();
1437 if ((*p)->binding() != elfcpp::STB_WEAK)
1440 // Build a circular list of weak aliases. Each symbol points to
1441 // the next one in the circular list.
1443 Sized_symbol<size>* from_sym = *p;
1444 typename std::vector<Sized_symbol<size>*>::const_iterator q;
1445 for (q = p + 1; q != symbols->end(); ++q)
1448 if ((*q)->shndx(&dummy) != from_sym->shndx(&dummy)
1449 || (*q)->value() != from_sym->value())
1452 this->weak_aliases_[from_sym] = *q;
1453 from_sym->set_has_alias();
1459 this->weak_aliases_[from_sym] = *p;
1460 from_sym->set_has_alias();
1467 // Create and return a specially defined symbol. If ONLY_IF_REF is
1468 // true, then only create the symbol if there is a reference to it.
1469 // If this does not return NULL, it sets *POLDSYM to the existing
1470 // symbol if there is one. This canonicalizes *PNAME and *PVERSION.
1472 template<int size, bool big_endian>
1474 Symbol_table::define_special_symbol(const char** pname, const char** pversion,
1476 Sized_symbol<size>** poldsym)
1479 Sized_symbol<size>* sym;
1480 bool add_to_table = false;
1481 typename Symbol_table_type::iterator add_loc = this->table_.end();
1483 // If the caller didn't give us a version, see if we get one from
1484 // the version script.
1486 if (*pversion == NULL)
1488 if (this->version_script_.get_symbol_version(*pname, &v))
1491 *pversion = v.c_str();
1497 oldsym = this->lookup(*pname, *pversion);
1498 if (oldsym == NULL || !oldsym->is_undefined())
1501 *pname = oldsym->name();
1502 *pversion = oldsym->version();
1506 // Canonicalize NAME and VERSION.
1507 Stringpool::Key name_key;
1508 *pname = this->namepool_.add(*pname, true, &name_key);
1510 Stringpool::Key version_key = 0;
1511 if (*pversion != NULL)
1512 *pversion = this->namepool_.add(*pversion, true, &version_key);
1514 Symbol* const snull = NULL;
1515 std::pair<typename Symbol_table_type::iterator, bool> ins =
1516 this->table_.insert(std::make_pair(std::make_pair(name_key,
1522 // We already have a symbol table entry for NAME/VERSION.
1523 oldsym = ins.first->second;
1524 gold_assert(oldsym != NULL);
1528 // We haven't seen this symbol before.
1529 gold_assert(ins.first->second == NULL);
1530 add_to_table = true;
1531 add_loc = ins.first;
1536 const Target& target = parameters->target();
1537 if (!target.has_make_symbol())
1538 sym = new Sized_symbol<size>();
1541 gold_assert(target.get_size() == size);
1542 gold_assert(target.is_big_endian() ? big_endian : !big_endian);
1543 typedef Sized_target<size, big_endian> My_target;
1544 const My_target* sized_target =
1545 static_cast<const My_target*>(&target);
1546 sym = sized_target->make_symbol();
1552 add_loc->second = sym;
1554 gold_assert(oldsym != NULL);
1556 *poldsym = this->get_sized_symbol<size>(oldsym);
1561 // Define a symbol based on an Output_data.
1564 Symbol_table::define_in_output_data(const char* name,
1565 const char* version,
1570 elfcpp::STB binding,
1571 elfcpp::STV visibility,
1572 unsigned char nonvis,
1573 bool offset_is_from_end,
1576 if (parameters->target().get_size() == 32)
1578 #if defined(HAVE_TARGET_32_LITTLE) || defined(HAVE_TARGET_32_BIG)
1579 return this->do_define_in_output_data<32>(name, version, od,
1580 value, symsize, type, binding,
1588 else if (parameters->target().get_size() == 64)
1590 #if defined(HAVE_TARGET_64_LITTLE) || defined(HAVE_TARGET_64_BIG)
1591 return this->do_define_in_output_data<64>(name, version, od,
1592 value, symsize, type, binding,
1604 // Define a symbol in an Output_data, sized version.
1608 Symbol_table::do_define_in_output_data(
1610 const char* version,
1612 typename elfcpp::Elf_types<size>::Elf_Addr value,
1613 typename elfcpp::Elf_types<size>::Elf_WXword symsize,
1615 elfcpp::STB binding,
1616 elfcpp::STV visibility,
1617 unsigned char nonvis,
1618 bool offset_is_from_end,
1621 Sized_symbol<size>* sym;
1622 Sized_symbol<size>* oldsym;
1624 if (parameters->target().is_big_endian())
1626 #if defined(HAVE_TARGET_32_BIG) || defined(HAVE_TARGET_64_BIG)
1627 sym = this->define_special_symbol<size, true>(&name, &version,
1628 only_if_ref, &oldsym);
1635 #if defined(HAVE_TARGET_32_LITTLE) || defined(HAVE_TARGET_64_LITTLE)
1636 sym = this->define_special_symbol<size, false>(&name, &version,
1637 only_if_ref, &oldsym);
1646 sym->init_output_data(name, version, od, value, symsize, type, binding,
1647 visibility, nonvis, offset_is_from_end);
1651 if (binding == elfcpp::STB_LOCAL
1652 || this->version_script_.symbol_is_local(name))
1653 this->force_local(sym);
1654 else if (version != NULL)
1655 sym->set_is_default();
1659 if (Symbol_table::should_override_with_special(oldsym))
1660 this->override_with_special(oldsym, sym);
1665 // Define a symbol based on an Output_segment.
1668 Symbol_table::define_in_output_segment(const char* name,
1669 const char* version, Output_segment* os,
1673 elfcpp::STB binding,
1674 elfcpp::STV visibility,
1675 unsigned char nonvis,
1676 Symbol::Segment_offset_base offset_base,
1679 if (parameters->target().get_size() == 32)
1681 #if defined(HAVE_TARGET_32_LITTLE) || defined(HAVE_TARGET_32_BIG)
1682 return this->do_define_in_output_segment<32>(name, version, os,
1683 value, symsize, type,
1684 binding, visibility, nonvis,
1685 offset_base, only_if_ref);
1690 else if (parameters->target().get_size() == 64)
1692 #if defined(HAVE_TARGET_64_LITTLE) || defined(HAVE_TARGET_64_BIG)
1693 return this->do_define_in_output_segment<64>(name, version, os,
1694 value, symsize, type,
1695 binding, visibility, nonvis,
1696 offset_base, only_if_ref);
1705 // Define a symbol in an Output_segment, sized version.
1709 Symbol_table::do_define_in_output_segment(
1711 const char* version,
1713 typename elfcpp::Elf_types<size>::Elf_Addr value,
1714 typename elfcpp::Elf_types<size>::Elf_WXword symsize,
1716 elfcpp::STB binding,
1717 elfcpp::STV visibility,
1718 unsigned char nonvis,
1719 Symbol::Segment_offset_base offset_base,
1722 Sized_symbol<size>* sym;
1723 Sized_symbol<size>* oldsym;
1725 if (parameters->target().is_big_endian())
1727 #if defined(HAVE_TARGET_32_BIG) || defined(HAVE_TARGET_64_BIG)
1728 sym = this->define_special_symbol<size, true>(&name, &version,
1729 only_if_ref, &oldsym);
1736 #if defined(HAVE_TARGET_32_LITTLE) || defined(HAVE_TARGET_64_LITTLE)
1737 sym = this->define_special_symbol<size, false>(&name, &version,
1738 only_if_ref, &oldsym);
1747 sym->init_output_segment(name, version, os, value, symsize, type, binding,
1748 visibility, nonvis, offset_base);
1752 if (binding == elfcpp::STB_LOCAL
1753 || this->version_script_.symbol_is_local(name))
1754 this->force_local(sym);
1755 else if (version != NULL)
1756 sym->set_is_default();
1760 if (Symbol_table::should_override_with_special(oldsym))
1761 this->override_with_special(oldsym, sym);
1766 // Define a special symbol with a constant value. It is a multiple
1767 // definition error if this symbol is already defined.
1770 Symbol_table::define_as_constant(const char* name,
1771 const char* version,
1775 elfcpp::STB binding,
1776 elfcpp::STV visibility,
1777 unsigned char nonvis,
1779 bool force_override)
1781 if (parameters->target().get_size() == 32)
1783 #if defined(HAVE_TARGET_32_LITTLE) || defined(HAVE_TARGET_32_BIG)
1784 return this->do_define_as_constant<32>(name, version, value,
1785 symsize, type, binding,
1786 visibility, nonvis, only_if_ref,
1792 else if (parameters->target().get_size() == 64)
1794 #if defined(HAVE_TARGET_64_LITTLE) || defined(HAVE_TARGET_64_BIG)
1795 return this->do_define_as_constant<64>(name, version, value,
1796 symsize, type, binding,
1797 visibility, nonvis, only_if_ref,
1807 // Define a symbol as a constant, sized version.
1811 Symbol_table::do_define_as_constant(
1813 const char* version,
1814 typename elfcpp::Elf_types<size>::Elf_Addr value,
1815 typename elfcpp::Elf_types<size>::Elf_WXword symsize,
1817 elfcpp::STB binding,
1818 elfcpp::STV visibility,
1819 unsigned char nonvis,
1821 bool force_override)
1823 Sized_symbol<size>* sym;
1824 Sized_symbol<size>* oldsym;
1826 if (parameters->target().is_big_endian())
1828 #if defined(HAVE_TARGET_32_BIG) || defined(HAVE_TARGET_64_BIG)
1829 sym = this->define_special_symbol<size, true>(&name, &version,
1830 only_if_ref, &oldsym);
1837 #if defined(HAVE_TARGET_32_LITTLE) || defined(HAVE_TARGET_64_LITTLE)
1838 sym = this->define_special_symbol<size, false>(&name, &version,
1839 only_if_ref, &oldsym);
1848 sym->init_constant(name, version, value, symsize, type, binding, visibility,
1853 // Version symbols are absolute symbols with name == version.
1854 // We don't want to force them to be local.
1855 if ((version == NULL
1858 && (binding == elfcpp::STB_LOCAL
1859 || this->version_script_.symbol_is_local(name)))
1860 this->force_local(sym);
1861 else if (version != NULL
1862 && (name != version || value != 0))
1863 sym->set_is_default();
1867 if (force_override || Symbol_table::should_override_with_special(oldsym))
1868 this->override_with_special(oldsym, sym);
1873 // Define a set of symbols in output sections.
1876 Symbol_table::define_symbols(const Layout* layout, int count,
1877 const Define_symbol_in_section* p,
1880 for (int i = 0; i < count; ++i, ++p)
1882 Output_section* os = layout->find_output_section(p->output_section);
1884 this->define_in_output_data(p->name, NULL, os, p->value,
1885 p->size, p->type, p->binding,
1886 p->visibility, p->nonvis,
1887 p->offset_is_from_end,
1888 only_if_ref || p->only_if_ref);
1890 this->define_as_constant(p->name, NULL, 0, p->size, p->type,
1891 p->binding, p->visibility, p->nonvis,
1892 only_if_ref || p->only_if_ref,
1897 // Define a set of symbols in output segments.
1900 Symbol_table::define_symbols(const Layout* layout, int count,
1901 const Define_symbol_in_segment* p,
1904 for (int i = 0; i < count; ++i, ++p)
1906 Output_segment* os = layout->find_output_segment(p->segment_type,
1907 p->segment_flags_set,
1908 p->segment_flags_clear);
1910 this->define_in_output_segment(p->name, NULL, os, p->value,
1911 p->size, p->type, p->binding,
1912 p->visibility, p->nonvis,
1914 only_if_ref || p->only_if_ref);
1916 this->define_as_constant(p->name, NULL, 0, p->size, p->type,
1917 p->binding, p->visibility, p->nonvis,
1918 only_if_ref || p->only_if_ref,
1923 // Define CSYM using a COPY reloc. POSD is the Output_data where the
1924 // symbol should be defined--typically a .dyn.bss section. VALUE is
1925 // the offset within POSD.
1929 Symbol_table::define_with_copy_reloc(
1930 Sized_symbol<size>* csym,
1932 typename elfcpp::Elf_types<size>::Elf_Addr value)
1934 gold_assert(csym->is_from_dynobj());
1935 gold_assert(!csym->is_copied_from_dynobj());
1936 Object* object = csym->object();
1937 gold_assert(object->is_dynamic());
1938 Dynobj* dynobj = static_cast<Dynobj*>(object);
1940 // Our copied variable has to override any variable in a shared
1942 elfcpp::STB binding = csym->binding();
1943 if (binding == elfcpp::STB_WEAK)
1944 binding = elfcpp::STB_GLOBAL;
1946 this->define_in_output_data(csym->name(), csym->version(),
1947 posd, value, csym->symsize(),
1948 csym->type(), binding,
1949 csym->visibility(), csym->nonvis(),
1952 csym->set_is_copied_from_dynobj();
1953 csym->set_needs_dynsym_entry();
1955 this->copied_symbol_dynobjs_[csym] = dynobj;
1957 // We have now defined all aliases, but we have not entered them all
1958 // in the copied_symbol_dynobjs_ map.
1959 if (csym->has_alias())
1964 sym = this->weak_aliases_[sym];
1967 gold_assert(sym->output_data() == posd);
1969 sym->set_is_copied_from_dynobj();
1970 this->copied_symbol_dynobjs_[sym] = dynobj;
1975 // SYM is defined using a COPY reloc. Return the dynamic object where
1976 // the original definition was found.
1979 Symbol_table::get_copy_source(const Symbol* sym) const
1981 gold_assert(sym->is_copied_from_dynobj());
1982 Copied_symbol_dynobjs::const_iterator p =
1983 this->copied_symbol_dynobjs_.find(sym);
1984 gold_assert(p != this->copied_symbol_dynobjs_.end());
1988 // Add any undefined symbols named on the command line.
1991 Symbol_table::add_undefined_symbols_from_command_line()
1993 if (parameters->options().any_undefined())
1995 if (parameters->target().get_size() == 32)
1997 #if defined(HAVE_TARGET_32_LITTLE) || defined(HAVE_TARGET_32_BIG)
1998 this->do_add_undefined_symbols_from_command_line<32>();
2003 else if (parameters->target().get_size() == 64)
2005 #if defined(HAVE_TARGET_64_LITTLE) || defined(HAVE_TARGET_64_BIG)
2006 this->do_add_undefined_symbols_from_command_line<64>();
2018 Symbol_table::do_add_undefined_symbols_from_command_line()
2020 for (options::String_set::const_iterator p =
2021 parameters->options().undefined_begin();
2022 p != parameters->options().undefined_end();
2025 const char* name = p->c_str();
2027 if (this->lookup(name) != NULL)
2030 const char* version = NULL;
2032 Sized_symbol<size>* sym;
2033 Sized_symbol<size>* oldsym;
2034 if (parameters->target().is_big_endian())
2036 #if defined(HAVE_TARGET_32_BIG) || defined(HAVE_TARGET_64_BIG)
2037 sym = this->define_special_symbol<size, true>(&name, &version,
2045 #if defined(HAVE_TARGET_32_LITTLE) || defined(HAVE_TARGET_64_LITTLE)
2046 sym = this->define_special_symbol<size, false>(&name, &version,
2053 gold_assert(oldsym == NULL);
2055 sym->init_undefined(name, version, elfcpp::STT_NOTYPE, elfcpp::STB_GLOBAL,
2056 elfcpp::STV_DEFAULT, 0);
2057 ++this->saw_undefined_;
2061 // Set the dynamic symbol indexes. INDEX is the index of the first
2062 // global dynamic symbol. Pointers to the symbols are stored into the
2063 // vector SYMS. The names are added to DYNPOOL. This returns an
2064 // updated dynamic symbol index.
2067 Symbol_table::set_dynsym_indexes(unsigned int index,
2068 std::vector<Symbol*>* syms,
2069 Stringpool* dynpool,
2072 for (Symbol_table_type::iterator p = this->table_.begin();
2073 p != this->table_.end();
2076 Symbol* sym = p->second;
2078 // Note that SYM may already have a dynamic symbol index, since
2079 // some symbols appear more than once in the symbol table, with
2080 // and without a version.
2082 if (!sym->should_add_dynsym_entry())
2083 sym->set_dynsym_index(-1U);
2084 else if (!sym->has_dynsym_index())
2086 sym->set_dynsym_index(index);
2088 syms->push_back(sym);
2089 dynpool->add(sym->name(), false, NULL);
2091 // Record any version information.
2092 if (sym->version() != NULL)
2093 versions->record_version(this, dynpool, sym);
2097 // Finish up the versions. In some cases this may add new dynamic
2099 index = versions->finalize(this, index, syms);
2104 // Set the final values for all the symbols. The index of the first
2105 // global symbol in the output file is *PLOCAL_SYMCOUNT. Record the
2106 // file offset OFF. Add their names to POOL. Return the new file
2107 // offset. Update *PLOCAL_SYMCOUNT if necessary.
2110 Symbol_table::finalize(off_t off, off_t dynoff, size_t dyn_global_index,
2111 size_t dyncount, Stringpool* pool,
2112 unsigned int *plocal_symcount)
2116 gold_assert(*plocal_symcount != 0);
2117 this->first_global_index_ = *plocal_symcount;
2119 this->dynamic_offset_ = dynoff;
2120 this->first_dynamic_global_index_ = dyn_global_index;
2121 this->dynamic_count_ = dyncount;
2123 if (parameters->target().get_size() == 32)
2125 #if defined(HAVE_TARGET_32_BIG) || defined(HAVE_TARGET_32_LITTLE)
2126 ret = this->sized_finalize<32>(off, pool, plocal_symcount);
2131 else if (parameters->target().get_size() == 64)
2133 #if defined(HAVE_TARGET_64_BIG) || defined(HAVE_TARGET_64_LITTLE)
2134 ret = this->sized_finalize<64>(off, pool, plocal_symcount);
2142 // Now that we have the final symbol table, we can reliably note
2143 // which symbols should get warnings.
2144 this->warnings_.note_warnings(this);
2149 // SYM is going into the symbol table at *PINDEX. Add the name to
2150 // POOL, update *PINDEX and *POFF.
2154 Symbol_table::add_to_final_symtab(Symbol* sym, Stringpool* pool,
2155 unsigned int* pindex, off_t* poff)
2157 sym->set_symtab_index(*pindex);
2158 pool->add(sym->name(), false, NULL);
2160 *poff += elfcpp::Elf_sizes<size>::sym_size;
2163 // Set the final value for all the symbols. This is called after
2164 // Layout::finalize, so all the output sections have their final
2169 Symbol_table::sized_finalize(off_t off, Stringpool* pool,
2170 unsigned int* plocal_symcount)
2172 off = align_address(off, size >> 3);
2173 this->offset_ = off;
2175 unsigned int index = *plocal_symcount;
2176 const unsigned int orig_index = index;
2178 // First do all the symbols which have been forced to be local, as
2179 // they must appear before all global symbols.
2180 for (Forced_locals::iterator p = this->forced_locals_.begin();
2181 p != this->forced_locals_.end();
2185 gold_assert(sym->is_forced_local());
2186 if (this->sized_finalize_symbol<size>(sym))
2188 this->add_to_final_symtab<size>(sym, pool, &index, &off);
2193 // Now do all the remaining symbols.
2194 for (Symbol_table_type::iterator p = this->table_.begin();
2195 p != this->table_.end();
2198 Symbol* sym = p->second;
2199 if (this->sized_finalize_symbol<size>(sym))
2200 this->add_to_final_symtab<size>(sym, pool, &index, &off);
2203 this->output_count_ = index - orig_index;
2208 // Finalize the symbol SYM. This returns true if the symbol should be
2209 // added to the symbol table, false otherwise.
2213 Symbol_table::sized_finalize_symbol(Symbol* unsized_sym)
2215 typedef typename Sized_symbol<size>::Value_type Value_type;
2217 Sized_symbol<size>* sym = static_cast<Sized_symbol<size>*>(unsized_sym);
2219 // The default version of a symbol may appear twice in the symbol
2220 // table. We only need to finalize it once.
2221 if (sym->has_symtab_index())
2226 gold_assert(!sym->has_symtab_index());
2227 sym->set_symtab_index(-1U);
2228 gold_assert(sym->dynsym_index() == -1U);
2234 switch (sym->source())
2236 case Symbol::FROM_OBJECT:
2239 unsigned int shndx = sym->shndx(&is_ordinary);
2241 // FIXME: We need some target specific support here.
2243 && shndx != elfcpp::SHN_ABS
2244 && shndx != elfcpp::SHN_COMMON)
2246 gold_error(_("%s: unsupported symbol section 0x%x"),
2247 sym->demangled_name().c_str(), shndx);
2248 shndx = elfcpp::SHN_UNDEF;
2251 Object* symobj = sym->object();
2252 if (symobj->is_dynamic())
2255 shndx = elfcpp::SHN_UNDEF;
2257 else if (symobj->pluginobj() != NULL)
2260 shndx = elfcpp::SHN_UNDEF;
2262 else if (shndx == elfcpp::SHN_UNDEF)
2264 else if (!is_ordinary
2265 && (shndx == elfcpp::SHN_ABS || shndx == elfcpp::SHN_COMMON))
2266 value = sym->value();
2269 Relobj* relobj = static_cast<Relobj*>(symobj);
2270 Output_section* os = relobj->output_section(shndx);
2274 sym->set_symtab_index(-1U);
2275 bool static_or_reloc = (parameters->doing_static_link() ||
2276 parameters->options().relocatable());
2277 gold_assert(static_or_reloc || sym->dynsym_index() == -1U);
2282 uint64_t secoff64 = relobj->output_section_offset(shndx);
2283 if (secoff64 == -1ULL)
2285 // The section needs special handling (e.g., a merge section).
2286 value = os->output_address(relobj, shndx, sym->value());
2291 convert_types<Value_type, uint64_t>(secoff64);
2292 if (sym->type() == elfcpp::STT_TLS)
2293 value = sym->value() + os->tls_offset() + secoff;
2295 value = sym->value() + os->address() + secoff;
2301 case Symbol::IN_OUTPUT_DATA:
2303 Output_data* od = sym->output_data();
2304 value = sym->value();
2305 if (sym->type() != elfcpp::STT_TLS)
2306 value += od->address();
2309 Output_section* os = od->output_section();
2310 gold_assert(os != NULL);
2311 value += os->tls_offset() + (od->address() - os->address());
2313 if (sym->offset_is_from_end())
2314 value += od->data_size();
2318 case Symbol::IN_OUTPUT_SEGMENT:
2320 Output_segment* os = sym->output_segment();
2321 value = sym->value();
2322 if (sym->type() != elfcpp::STT_TLS)
2323 value += os->vaddr();
2324 switch (sym->offset_base())
2326 case Symbol::SEGMENT_START:
2328 case Symbol::SEGMENT_END:
2329 value += os->memsz();
2331 case Symbol::SEGMENT_BSS:
2332 value += os->filesz();
2340 case Symbol::IS_CONSTANT:
2341 value = sym->value();
2344 case Symbol::IS_UNDEFINED:
2352 sym->set_value(value);
2354 if (parameters->options().strip_all())
2356 sym->set_symtab_index(-1U);
2363 // Write out the global symbols.
2366 Symbol_table::write_globals(const Input_objects* input_objects,
2367 const Stringpool* sympool,
2368 const Stringpool* dynpool,
2369 Output_symtab_xindex* symtab_xindex,
2370 Output_symtab_xindex* dynsym_xindex,
2371 Output_file* of) const
2373 switch (parameters->size_and_endianness())
2375 #ifdef HAVE_TARGET_32_LITTLE
2376 case Parameters::TARGET_32_LITTLE:
2377 this->sized_write_globals<32, false>(input_objects, sympool,
2378 dynpool, symtab_xindex,
2382 #ifdef HAVE_TARGET_32_BIG
2383 case Parameters::TARGET_32_BIG:
2384 this->sized_write_globals<32, true>(input_objects, sympool,
2385 dynpool, symtab_xindex,
2389 #ifdef HAVE_TARGET_64_LITTLE
2390 case Parameters::TARGET_64_LITTLE:
2391 this->sized_write_globals<64, false>(input_objects, sympool,
2392 dynpool, symtab_xindex,
2396 #ifdef HAVE_TARGET_64_BIG
2397 case Parameters::TARGET_64_BIG:
2398 this->sized_write_globals<64, true>(input_objects, sympool,
2399 dynpool, symtab_xindex,
2408 // Write out the global symbols.
2410 template<int size, bool big_endian>
2412 Symbol_table::sized_write_globals(const Input_objects* input_objects,
2413 const Stringpool* sympool,
2414 const Stringpool* dynpool,
2415 Output_symtab_xindex* symtab_xindex,
2416 Output_symtab_xindex* dynsym_xindex,
2417 Output_file* of) const
2419 const Target& target = parameters->target();
2421 const int sym_size = elfcpp::Elf_sizes<size>::sym_size;
2423 const unsigned int output_count = this->output_count_;
2424 const section_size_type oview_size = output_count * sym_size;
2425 const unsigned int first_global_index = this->first_global_index_;
2426 unsigned char* psyms;
2427 if (this->offset_ == 0 || output_count == 0)
2430 psyms = of->get_output_view(this->offset_, oview_size);
2432 const unsigned int dynamic_count = this->dynamic_count_;
2433 const section_size_type dynamic_size = dynamic_count * sym_size;
2434 const unsigned int first_dynamic_global_index =
2435 this->first_dynamic_global_index_;
2436 unsigned char* dynamic_view;
2437 if (this->dynamic_offset_ == 0 || dynamic_count == 0)
2438 dynamic_view = NULL;
2440 dynamic_view = of->get_output_view(this->dynamic_offset_, dynamic_size);
2442 for (Symbol_table_type::const_iterator p = this->table_.begin();
2443 p != this->table_.end();
2446 Sized_symbol<size>* sym = static_cast<Sized_symbol<size>*>(p->second);
2448 // Possibly warn about unresolved symbols in shared libraries.
2449 this->warn_about_undefined_dynobj_symbol(input_objects, sym);
2451 unsigned int sym_index = sym->symtab_index();
2452 unsigned int dynsym_index;
2453 if (dynamic_view == NULL)
2456 dynsym_index = sym->dynsym_index();
2458 if (sym_index == -1U && dynsym_index == -1U)
2460 // This symbol is not included in the output file.
2465 typename elfcpp::Elf_types<size>::Elf_Addr sym_value = sym->value();
2466 typename elfcpp::Elf_types<size>::Elf_Addr dynsym_value = sym_value;
2467 switch (sym->source())
2469 case Symbol::FROM_OBJECT:
2472 unsigned int in_shndx = sym->shndx(&is_ordinary);
2474 // FIXME: We need some target specific support here.
2476 && in_shndx != elfcpp::SHN_ABS
2477 && in_shndx != elfcpp::SHN_COMMON)
2479 gold_error(_("%s: unsupported symbol section 0x%x"),
2480 sym->demangled_name().c_str(), in_shndx);
2485 Object* symobj = sym->object();
2486 if (symobj->is_dynamic())
2488 if (sym->needs_dynsym_value())
2489 dynsym_value = target.dynsym_value(sym);
2490 shndx = elfcpp::SHN_UNDEF;
2492 else if (symobj->pluginobj() != NULL)
2493 shndx = elfcpp::SHN_UNDEF;
2494 else if (in_shndx == elfcpp::SHN_UNDEF
2496 && (in_shndx == elfcpp::SHN_ABS
2497 || in_shndx == elfcpp::SHN_COMMON)))
2501 Relobj* relobj = static_cast<Relobj*>(symobj);
2502 Output_section* os = relobj->output_section(in_shndx);
2503 gold_assert(os != NULL);
2504 shndx = os->out_shndx();
2506 if (shndx >= elfcpp::SHN_LORESERVE)
2508 if (sym_index != -1U)
2509 symtab_xindex->add(sym_index, shndx);
2510 if (dynsym_index != -1U)
2511 dynsym_xindex->add(dynsym_index, shndx);
2512 shndx = elfcpp::SHN_XINDEX;
2515 // In object files symbol values are section
2517 if (parameters->options().relocatable())
2518 sym_value -= os->address();
2524 case Symbol::IN_OUTPUT_DATA:
2525 shndx = sym->output_data()->out_shndx();
2526 if (shndx >= elfcpp::SHN_LORESERVE)
2528 if (sym_index != -1U)
2529 symtab_xindex->add(sym_index, shndx);
2530 if (dynsym_index != -1U)
2531 dynsym_xindex->add(dynsym_index, shndx);
2532 shndx = elfcpp::SHN_XINDEX;
2536 case Symbol::IN_OUTPUT_SEGMENT:
2537 shndx = elfcpp::SHN_ABS;
2540 case Symbol::IS_CONSTANT:
2541 shndx = elfcpp::SHN_ABS;
2544 case Symbol::IS_UNDEFINED:
2545 shndx = elfcpp::SHN_UNDEF;
2552 if (sym_index != -1U)
2554 sym_index -= first_global_index;
2555 gold_assert(sym_index < output_count);
2556 unsigned char* ps = psyms + (sym_index * sym_size);
2557 this->sized_write_symbol<size, big_endian>(sym, sym_value, shndx,
2561 if (dynsym_index != -1U)
2563 dynsym_index -= first_dynamic_global_index;
2564 gold_assert(dynsym_index < dynamic_count);
2565 unsigned char* pd = dynamic_view + (dynsym_index * sym_size);
2566 this->sized_write_symbol<size, big_endian>(sym, dynsym_value, shndx,
2571 of->write_output_view(this->offset_, oview_size, psyms);
2572 if (dynamic_view != NULL)
2573 of->write_output_view(this->dynamic_offset_, dynamic_size, dynamic_view);
2576 // Write out the symbol SYM, in section SHNDX, to P. POOL is the
2577 // strtab holding the name.
2579 template<int size, bool big_endian>
2581 Symbol_table::sized_write_symbol(
2582 Sized_symbol<size>* sym,
2583 typename elfcpp::Elf_types<size>::Elf_Addr value,
2585 const Stringpool* pool,
2586 unsigned char* p) const
2588 elfcpp::Sym_write<size, big_endian> osym(p);
2589 osym.put_st_name(pool->get_offset(sym->name()));
2590 osym.put_st_value(value);
2591 // Use a symbol size of zero for undefined symbols from shared libraries.
2592 if (shndx == elfcpp::SHN_UNDEF && sym->is_from_dynobj())
2593 osym.put_st_size(0);
2595 osym.put_st_size(sym->symsize());
2596 // A version script may have overridden the default binding.
2597 if (sym->is_forced_local())
2598 osym.put_st_info(elfcpp::elf_st_info(elfcpp::STB_LOCAL, sym->type()));
2600 osym.put_st_info(elfcpp::elf_st_info(sym->binding(), sym->type()));
2601 osym.put_st_other(elfcpp::elf_st_other(sym->visibility(), sym->nonvis()));
2602 osym.put_st_shndx(shndx);
2605 // Check for unresolved symbols in shared libraries. This is
2606 // controlled by the --allow-shlib-undefined option.
2608 // We only warn about libraries for which we have seen all the
2609 // DT_NEEDED entries. We don't try to track down DT_NEEDED entries
2610 // which were not seen in this link. If we didn't see a DT_NEEDED
2611 // entry, we aren't going to be able to reliably report whether the
2612 // symbol is undefined.
2614 // We also don't warn about libraries found in the system library
2615 // directory (the directory were we find libc.so); we assume that
2616 // those libraries are OK. This heuristic avoids problems in
2617 // GNU/Linux, in which -ldl can have undefined references satisfied by
2621 Symbol_table::warn_about_undefined_dynobj_symbol(
2622 const Input_objects* input_objects,
2626 if (sym->source() == Symbol::FROM_OBJECT
2627 && sym->object()->is_dynamic()
2628 && sym->shndx(&dummy) == elfcpp::SHN_UNDEF
2629 && sym->binding() != elfcpp::STB_WEAK
2630 && !parameters->options().allow_shlib_undefined()
2631 && !parameters->target().is_defined_by_abi(sym)
2632 && !input_objects->found_in_system_library_directory(sym->object()))
2634 // A very ugly cast.
2635 Dynobj* dynobj = static_cast<Dynobj*>(sym->object());
2636 if (!dynobj->has_unknown_needed_entries())
2637 gold_undefined_symbol(sym);
2641 // Write out a section symbol. Return the update offset.
2644 Symbol_table::write_section_symbol(const Output_section *os,
2645 Output_symtab_xindex* symtab_xindex,
2649 switch (parameters->size_and_endianness())
2651 #ifdef HAVE_TARGET_32_LITTLE
2652 case Parameters::TARGET_32_LITTLE:
2653 this->sized_write_section_symbol<32, false>(os, symtab_xindex, of,
2657 #ifdef HAVE_TARGET_32_BIG
2658 case Parameters::TARGET_32_BIG:
2659 this->sized_write_section_symbol<32, true>(os, symtab_xindex, of,
2663 #ifdef HAVE_TARGET_64_LITTLE
2664 case Parameters::TARGET_64_LITTLE:
2665 this->sized_write_section_symbol<64, false>(os, symtab_xindex, of,
2669 #ifdef HAVE_TARGET_64_BIG
2670 case Parameters::TARGET_64_BIG:
2671 this->sized_write_section_symbol<64, true>(os, symtab_xindex, of,
2680 // Write out a section symbol, specialized for size and endianness.
2682 template<int size, bool big_endian>
2684 Symbol_table::sized_write_section_symbol(const Output_section* os,
2685 Output_symtab_xindex* symtab_xindex,
2689 const int sym_size = elfcpp::Elf_sizes<size>::sym_size;
2691 unsigned char* pov = of->get_output_view(offset, sym_size);
2693 elfcpp::Sym_write<size, big_endian> osym(pov);
2694 osym.put_st_name(0);
2695 osym.put_st_value(os->address());
2696 osym.put_st_size(0);
2697 osym.put_st_info(elfcpp::elf_st_info(elfcpp::STB_LOCAL,
2698 elfcpp::STT_SECTION));
2699 osym.put_st_other(elfcpp::elf_st_other(elfcpp::STV_DEFAULT, 0));
2701 unsigned int shndx = os->out_shndx();
2702 if (shndx >= elfcpp::SHN_LORESERVE)
2704 symtab_xindex->add(os->symtab_index(), shndx);
2705 shndx = elfcpp::SHN_XINDEX;
2707 osym.put_st_shndx(shndx);
2709 of->write_output_view(offset, sym_size, pov);
2712 // Print statistical information to stderr. This is used for --stats.
2715 Symbol_table::print_stats() const
2717 #if defined(HAVE_TR1_UNORDERED_MAP) || defined(HAVE_EXT_HASH_MAP)
2718 fprintf(stderr, _("%s: symbol table entries: %zu; buckets: %zu\n"),
2719 program_name, this->table_.size(), this->table_.bucket_count());
2721 fprintf(stderr, _("%s: symbol table entries: %zu\n"),
2722 program_name, this->table_.size());
2724 this->namepool_.print_stats("symbol table stringpool");
2727 // We check for ODR violations by looking for symbols with the same
2728 // name for which the debugging information reports that they were
2729 // defined in different source locations. When comparing the source
2730 // location, we consider instances with the same base filename and
2731 // line number to be the same. This is because different object
2732 // files/shared libraries can include the same header file using
2733 // different paths, and we don't want to report an ODR violation in
2736 // This struct is used to compare line information, as returned by
2737 // Dwarf_line_info::one_addr2line. It implements a < comparison
2738 // operator used with std::set.
2740 struct Odr_violation_compare
2743 operator()(const std::string& s1, const std::string& s2) const
2745 std::string::size_type pos1 = s1.rfind('/');
2746 std::string::size_type pos2 = s2.rfind('/');
2747 if (pos1 == std::string::npos
2748 || pos2 == std::string::npos)
2750 return s1.compare(pos1, std::string::npos,
2751 s2, pos2, std::string::npos) < 0;
2755 // Check candidate_odr_violations_ to find symbols with the same name
2756 // but apparently different definitions (different source-file/line-no).
2759 Symbol_table::detect_odr_violations(const Task* task,
2760 const char* output_file_name) const
2762 for (Odr_map::const_iterator it = candidate_odr_violations_.begin();
2763 it != candidate_odr_violations_.end();
2766 const char* symbol_name = it->first;
2767 // We use a sorted set so the output is deterministic.
2768 std::set<std::string, Odr_violation_compare> line_nums;
2770 for (Unordered_set<Symbol_location, Symbol_location_hash>::const_iterator
2771 locs = it->second.begin();
2772 locs != it->second.end();
2775 // We need to lock the object in order to read it. This
2776 // means that we have to run in a singleton Task. If we
2777 // want to run this in a general Task for better
2778 // performance, we will need one Task for object, plus
2779 // appropriate locking to ensure that we don't conflict with
2780 // other uses of the object. Also note, one_addr2line is not
2781 // currently thread-safe.
2782 Task_lock_obj<Object> tl(task, locs->object);
2783 // 16 is the size of the object-cache that one_addr2line should use.
2784 std::string lineno = Dwarf_line_info::one_addr2line(
2785 locs->object, locs->shndx, locs->offset, 16);
2786 if (!lineno.empty())
2787 line_nums.insert(lineno);
2790 if (line_nums.size() > 1)
2792 gold_warning(_("while linking %s: symbol '%s' defined in multiple "
2793 "places (possible ODR violation):"),
2794 output_file_name, demangle(symbol_name).c_str());
2795 for (std::set<std::string>::const_iterator it2 = line_nums.begin();
2796 it2 != line_nums.end();
2798 fprintf(stderr, " %s\n", it2->c_str());
2801 // We only call one_addr2line() in this function, so we can clear its cache.
2802 Dwarf_line_info::clear_addr2line_cache();
2805 // Warnings functions.
2807 // Add a new warning.
2810 Warnings::add_warning(Symbol_table* symtab, const char* name, Object* obj,
2811 const std::string& warning)
2813 name = symtab->canonicalize_name(name);
2814 this->warnings_[name].set(obj, warning);
2817 // Look through the warnings and mark the symbols for which we should
2818 // warn. This is called during Layout::finalize when we know the
2819 // sources for all the symbols.
2822 Warnings::note_warnings(Symbol_table* symtab)
2824 for (Warning_table::iterator p = this->warnings_.begin();
2825 p != this->warnings_.end();
2828 Symbol* sym = symtab->lookup(p->first, NULL);
2830 && sym->source() == Symbol::FROM_OBJECT
2831 && sym->object() == p->second.object)
2832 sym->set_has_warning();
2836 // Issue a warning. This is called when we see a relocation against a
2837 // symbol for which has a warning.
2839 template<int size, bool big_endian>
2841 Warnings::issue_warning(const Symbol* sym,
2842 const Relocate_info<size, big_endian>* relinfo,
2843 size_t relnum, off_t reloffset) const
2845 gold_assert(sym->has_warning());
2846 Warning_table::const_iterator p = this->warnings_.find(sym->name());
2847 gold_assert(p != this->warnings_.end());
2848 gold_warning_at_location(relinfo, relnum, reloffset,
2849 "%s", p->second.text.c_str());
2852 // Instantiate the templates we need. We could use the configure
2853 // script to restrict this to only the ones needed for implemented
2856 #if defined(HAVE_TARGET_32_LITTLE) || defined(HAVE_TARGET_32_BIG)
2859 Sized_symbol<32>::allocate_common(Output_data*, Value_type);
2862 #if defined(HAVE_TARGET_64_LITTLE) || defined(HAVE_TARGET_64_BIG)
2865 Sized_symbol<64>::allocate_common(Output_data*, Value_type);
2868 #ifdef HAVE_TARGET_32_LITTLE
2871 Symbol_table::add_from_relobj<32, false>(
2872 Sized_relobj<32, false>* relobj,
2873 const unsigned char* syms,
2875 size_t symndx_offset,
2876 const char* sym_names,
2877 size_t sym_name_size,
2878 Sized_relobj<32, false>::Symbols* sympointers,
2882 #ifdef HAVE_TARGET_32_BIG
2885 Symbol_table::add_from_relobj<32, true>(
2886 Sized_relobj<32, true>* relobj,
2887 const unsigned char* syms,
2889 size_t symndx_offset,
2890 const char* sym_names,
2891 size_t sym_name_size,
2892 Sized_relobj<32, true>::Symbols* sympointers,
2896 #ifdef HAVE_TARGET_64_LITTLE
2899 Symbol_table::add_from_relobj<64, false>(
2900 Sized_relobj<64, false>* relobj,
2901 const unsigned char* syms,
2903 size_t symndx_offset,
2904 const char* sym_names,
2905 size_t sym_name_size,
2906 Sized_relobj<64, false>::Symbols* sympointers,
2910 #ifdef HAVE_TARGET_64_BIG
2913 Symbol_table::add_from_relobj<64, true>(
2914 Sized_relobj<64, true>* relobj,
2915 const unsigned char* syms,
2917 size_t symndx_offset,
2918 const char* sym_names,
2919 size_t sym_name_size,
2920 Sized_relobj<64, true>::Symbols* sympointers,
2924 #ifdef HAVE_TARGET_32_LITTLE
2927 Symbol_table::add_from_pluginobj<32, false>(
2928 Sized_pluginobj<32, false>* obj,
2931 elfcpp::Sym<32, false>* sym);
2934 #ifdef HAVE_TARGET_32_BIG
2937 Symbol_table::add_from_pluginobj<32, true>(
2938 Sized_pluginobj<32, true>* obj,
2941 elfcpp::Sym<32, true>* sym);
2944 #ifdef HAVE_TARGET_64_LITTLE
2947 Symbol_table::add_from_pluginobj<64, false>(
2948 Sized_pluginobj<64, false>* obj,
2951 elfcpp::Sym<64, false>* sym);
2954 #ifdef HAVE_TARGET_64_BIG
2957 Symbol_table::add_from_pluginobj<64, true>(
2958 Sized_pluginobj<64, true>* obj,
2961 elfcpp::Sym<64, true>* sym);
2964 #ifdef HAVE_TARGET_32_LITTLE
2967 Symbol_table::add_from_dynobj<32, false>(
2968 Sized_dynobj<32, false>* dynobj,
2969 const unsigned char* syms,
2971 const char* sym_names,
2972 size_t sym_name_size,
2973 const unsigned char* versym,
2975 const std::vector<const char*>* version_map,
2976 Sized_relobj<32, false>::Symbols* sympointers,
2980 #ifdef HAVE_TARGET_32_BIG
2983 Symbol_table::add_from_dynobj<32, true>(
2984 Sized_dynobj<32, true>* dynobj,
2985 const unsigned char* syms,
2987 const char* sym_names,
2988 size_t sym_name_size,
2989 const unsigned char* versym,
2991 const std::vector<const char*>* version_map,
2992 Sized_relobj<32, true>::Symbols* sympointers,
2996 #ifdef HAVE_TARGET_64_LITTLE
2999 Symbol_table::add_from_dynobj<64, false>(
3000 Sized_dynobj<64, false>* dynobj,
3001 const unsigned char* syms,
3003 const char* sym_names,
3004 size_t sym_name_size,
3005 const unsigned char* versym,
3007 const std::vector<const char*>* version_map,
3008 Sized_relobj<64, false>::Symbols* sympointers,
3012 #ifdef HAVE_TARGET_64_BIG
3015 Symbol_table::add_from_dynobj<64, true>(
3016 Sized_dynobj<64, true>* dynobj,
3017 const unsigned char* syms,
3019 const char* sym_names,
3020 size_t sym_name_size,
3021 const unsigned char* versym,
3023 const std::vector<const char*>* version_map,
3024 Sized_relobj<64, true>::Symbols* sympointers,
3028 #if defined(HAVE_TARGET_32_LITTLE) || defined(HAVE_TARGET_32_BIG)
3031 Symbol_table::define_with_copy_reloc<32>(
3032 Sized_symbol<32>* sym,
3034 elfcpp::Elf_types<32>::Elf_Addr value);
3037 #if defined(HAVE_TARGET_64_LITTLE) || defined(HAVE_TARGET_64_BIG)
3040 Symbol_table::define_with_copy_reloc<64>(
3041 Sized_symbol<64>* sym,
3043 elfcpp::Elf_types<64>::Elf_Addr value);
3046 #ifdef HAVE_TARGET_32_LITTLE
3049 Warnings::issue_warning<32, false>(const Symbol* sym,
3050 const Relocate_info<32, false>* relinfo,
3051 size_t relnum, off_t reloffset) const;
3054 #ifdef HAVE_TARGET_32_BIG
3057 Warnings::issue_warning<32, true>(const Symbol* sym,
3058 const Relocate_info<32, true>* relinfo,
3059 size_t relnum, off_t reloffset) const;
3062 #ifdef HAVE_TARGET_64_LITTLE
3065 Warnings::issue_warning<64, false>(const Symbol* sym,
3066 const Relocate_info<64, false>* relinfo,
3067 size_t relnum, off_t reloffset) const;
3070 #ifdef HAVE_TARGET_64_BIG
3073 Warnings::issue_warning<64, true>(const Symbol* sym,
3074 const Relocate_info<64, true>* relinfo,
3075 size_t relnum, off_t reloffset) const;
3078 } // End namespace gold.