1 // symtab.cc -- the gold symbol table
3 // Copyright (C) 2006-2014 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"
43 #include "incremental.h"
50 // Initialize fields in Symbol. This initializes everything except u_
54 Symbol::init_fields(const char* name
, const char* version
,
55 elfcpp::STT type
, elfcpp::STB binding
,
56 elfcpp::STV visibility
, unsigned char nonvis
)
59 this->version_
= version
;
60 this->symtab_index_
= 0;
61 this->dynsym_index_
= 0;
62 this->got_offsets_
.init();
63 this->plt_offset_
= -1U;
65 this->binding_
= binding
;
66 this->visibility_
= visibility
;
67 this->nonvis_
= nonvis
;
68 this->is_def_
= false;
69 this->is_forwarder_
= false;
70 this->has_alias_
= false;
71 this->needs_dynsym_entry_
= false;
72 this->in_reg_
= false;
73 this->in_dyn_
= false;
74 this->has_warning_
= false;
75 this->is_copied_from_dynobj_
= false;
76 this->is_forced_local_
= false;
77 this->is_ordinary_shndx_
= false;
78 this->in_real_elf_
= false;
79 this->is_defined_in_discarded_section_
= false;
80 this->undef_binding_set_
= false;
81 this->undef_binding_weak_
= false;
82 this->is_predefined_
= false;
85 // Return the demangled version of the symbol's name, but only
86 // if the --demangle flag was set.
89 demangle(const char* name
)
91 if (!parameters
->options().do_demangle())
94 // cplus_demangle allocates memory for the result it returns,
95 // and returns NULL if the name is already demangled.
96 char* demangled_name
= cplus_demangle(name
, DMGL_ANSI
| DMGL_PARAMS
);
97 if (demangled_name
== NULL
)
100 std::string
retval(demangled_name
);
101 free(demangled_name
);
106 Symbol::demangled_name() const
108 return demangle(this->name());
111 // Initialize the fields in the base class Symbol for SYM in OBJECT.
113 template<int size
, bool big_endian
>
115 Symbol::init_base_object(const char* name
, const char* version
, Object
* object
,
116 const elfcpp::Sym
<size
, big_endian
>& sym
,
117 unsigned int st_shndx
, bool is_ordinary
)
119 this->init_fields(name
, version
, sym
.get_st_type(), sym
.get_st_bind(),
120 sym
.get_st_visibility(), sym
.get_st_nonvis());
121 this->u_
.from_object
.object
= object
;
122 this->u_
.from_object
.shndx
= st_shndx
;
123 this->is_ordinary_shndx_
= is_ordinary
;
124 this->source_
= FROM_OBJECT
;
125 this->in_reg_
= !object
->is_dynamic();
126 this->in_dyn_
= object
->is_dynamic();
127 this->in_real_elf_
= object
->pluginobj() == NULL
;
130 // Initialize the fields in the base class Symbol for a symbol defined
131 // in an Output_data.
134 Symbol::init_base_output_data(const char* name
, const char* version
,
135 Output_data
* od
, elfcpp::STT type
,
136 elfcpp::STB binding
, elfcpp::STV visibility
,
137 unsigned char nonvis
, bool offset_is_from_end
,
140 this->init_fields(name
, version
, type
, binding
, visibility
, nonvis
);
141 this->u_
.in_output_data
.output_data
= od
;
142 this->u_
.in_output_data
.offset_is_from_end
= offset_is_from_end
;
143 this->source_
= IN_OUTPUT_DATA
;
144 this->in_reg_
= true;
145 this->in_real_elf_
= true;
146 this->is_predefined_
= is_predefined
;
149 // Initialize the fields in the base class Symbol for a symbol defined
150 // in an Output_segment.
153 Symbol::init_base_output_segment(const char* name
, const char* version
,
154 Output_segment
* os
, elfcpp::STT type
,
155 elfcpp::STB binding
, elfcpp::STV visibility
,
156 unsigned char nonvis
,
157 Segment_offset_base offset_base
,
160 this->init_fields(name
, version
, type
, binding
, visibility
, nonvis
);
161 this->u_
.in_output_segment
.output_segment
= os
;
162 this->u_
.in_output_segment
.offset_base
= offset_base
;
163 this->source_
= IN_OUTPUT_SEGMENT
;
164 this->in_reg_
= true;
165 this->in_real_elf_
= true;
166 this->is_predefined_
= is_predefined
;
169 // Initialize the fields in the base class Symbol for a symbol defined
173 Symbol::init_base_constant(const char* name
, const char* version
,
174 elfcpp::STT type
, elfcpp::STB binding
,
175 elfcpp::STV visibility
, unsigned char nonvis
,
178 this->init_fields(name
, version
, type
, binding
, visibility
, nonvis
);
179 this->source_
= IS_CONSTANT
;
180 this->in_reg_
= true;
181 this->in_real_elf_
= true;
182 this->is_predefined_
= is_predefined
;
185 // Initialize the fields in the base class Symbol for an undefined
189 Symbol::init_base_undefined(const char* name
, const char* version
,
190 elfcpp::STT type
, elfcpp::STB binding
,
191 elfcpp::STV visibility
, unsigned char nonvis
)
193 this->init_fields(name
, version
, type
, binding
, visibility
, nonvis
);
194 this->dynsym_index_
= -1U;
195 this->source_
= IS_UNDEFINED
;
196 this->in_reg_
= true;
197 this->in_real_elf_
= true;
200 // Allocate a common symbol in the base.
203 Symbol::allocate_base_common(Output_data
* od
)
205 gold_assert(this->is_common());
206 this->source_
= IN_OUTPUT_DATA
;
207 this->u_
.in_output_data
.output_data
= od
;
208 this->u_
.in_output_data
.offset_is_from_end
= false;
211 // Initialize the fields in Sized_symbol for SYM in OBJECT.
214 template<bool big_endian
>
216 Sized_symbol
<size
>::init_object(const char* name
, const char* version
,
218 const elfcpp::Sym
<size
, big_endian
>& sym
,
219 unsigned int st_shndx
, bool is_ordinary
)
221 this->init_base_object(name
, version
, object
, sym
, st_shndx
, is_ordinary
);
222 this->value_
= sym
.get_st_value();
223 this->symsize_
= sym
.get_st_size();
226 // Initialize the fields in Sized_symbol for a symbol defined in an
231 Sized_symbol
<size
>::init_output_data(const char* name
, const char* version
,
232 Output_data
* od
, Value_type value
,
233 Size_type symsize
, elfcpp::STT type
,
235 elfcpp::STV visibility
,
236 unsigned char nonvis
,
237 bool offset_is_from_end
,
240 this->init_base_output_data(name
, version
, od
, type
, binding
, visibility
,
241 nonvis
, offset_is_from_end
, is_predefined
);
242 this->value_
= value
;
243 this->symsize_
= symsize
;
246 // Initialize the fields in Sized_symbol for a symbol defined in an
251 Sized_symbol
<size
>::init_output_segment(const char* name
, const char* version
,
252 Output_segment
* os
, Value_type value
,
253 Size_type symsize
, elfcpp::STT type
,
255 elfcpp::STV visibility
,
256 unsigned char nonvis
,
257 Segment_offset_base offset_base
,
260 this->init_base_output_segment(name
, version
, os
, type
, binding
, visibility
,
261 nonvis
, offset_base
, is_predefined
);
262 this->value_
= value
;
263 this->symsize_
= symsize
;
266 // Initialize the fields in Sized_symbol for a symbol defined as a
271 Sized_symbol
<size
>::init_constant(const char* name
, const char* version
,
272 Value_type value
, Size_type symsize
,
273 elfcpp::STT type
, elfcpp::STB binding
,
274 elfcpp::STV visibility
, unsigned char nonvis
,
277 this->init_base_constant(name
, version
, type
, binding
, visibility
, nonvis
,
279 this->value_
= value
;
280 this->symsize_
= symsize
;
283 // Initialize the fields in Sized_symbol for an undefined symbol.
287 Sized_symbol
<size
>::init_undefined(const char* name
, const char* version
,
288 elfcpp::STT type
, elfcpp::STB binding
,
289 elfcpp::STV visibility
, unsigned char nonvis
)
291 this->init_base_undefined(name
, version
, type
, binding
, visibility
, nonvis
);
296 // Return an allocated string holding the symbol's name as
297 // name@version. This is used for relocatable links.
300 Symbol::versioned_name() const
302 gold_assert(this->version_
!= NULL
);
303 std::string ret
= this->name_
;
307 ret
+= this->version_
;
311 // Return true if SHNDX represents a common symbol.
314 Symbol::is_common_shndx(unsigned int shndx
)
316 return (shndx
== elfcpp::SHN_COMMON
317 || shndx
== parameters
->target().small_common_shndx()
318 || shndx
== parameters
->target().large_common_shndx());
321 // Allocate a common symbol.
325 Sized_symbol
<size
>::allocate_common(Output_data
* od
, Value_type value
)
327 this->allocate_base_common(od
);
328 this->value_
= value
;
331 // The ""'s around str ensure str is a string literal, so sizeof works.
332 #define strprefix(var, str) (strncmp(var, str, sizeof("" str "") - 1) == 0)
334 // Return true if this symbol should be added to the dynamic symbol
338 Symbol::should_add_dynsym_entry(Symbol_table
* symtab
) const
340 // If the symbol is only present on plugin files, the plugin decided we
342 if (!this->in_real_elf())
345 // If the symbol is used by a dynamic relocation, we need to add it.
346 if (this->needs_dynsym_entry())
349 // If this symbol's section is not added, the symbol need not be added.
350 // The section may have been GCed. Note that export_dynamic is being
351 // overridden here. This should not be done for shared objects.
352 if (parameters
->options().gc_sections()
353 && !parameters
->options().shared()
354 && this->source() == Symbol::FROM_OBJECT
355 && !this->object()->is_dynamic())
357 Relobj
* relobj
= static_cast<Relobj
*>(this->object());
359 unsigned int shndx
= this->shndx(&is_ordinary
);
360 if (is_ordinary
&& shndx
!= elfcpp::SHN_UNDEF
361 && !relobj
->is_section_included(shndx
)
362 && !symtab
->is_section_folded(relobj
, shndx
))
366 // If the symbol was forced dynamic in a --dynamic-list file
367 // or an --export-dynamic-symbol option, add it.
368 if (!this->is_from_dynobj()
369 && (parameters
->options().in_dynamic_list(this->name())
370 || parameters
->options().is_export_dynamic_symbol(this->name())))
372 if (!this->is_forced_local())
374 gold_warning(_("Cannot export local symbol '%s'"),
375 this->demangled_name().c_str());
379 // If the symbol was forced local in a version script, do not add it.
380 if (this->is_forced_local())
383 // If dynamic-list-data was specified, add any STT_OBJECT.
384 if (parameters
->options().dynamic_list_data()
385 && !this->is_from_dynobj()
386 && this->type() == elfcpp::STT_OBJECT
)
389 // If --dynamic-list-cpp-new was specified, add any new/delete symbol.
390 // If --dynamic-list-cpp-typeinfo was specified, add any typeinfo symbols.
391 if ((parameters
->options().dynamic_list_cpp_new()
392 || parameters
->options().dynamic_list_cpp_typeinfo())
393 && !this->is_from_dynobj())
395 // TODO(csilvers): We could probably figure out if we're an operator
396 // new/delete or typeinfo without the need to demangle.
397 char* demangled_name
= cplus_demangle(this->name(),
398 DMGL_ANSI
| DMGL_PARAMS
);
399 if (demangled_name
== NULL
)
401 // Not a C++ symbol, so it can't satisfy these flags
403 else if (parameters
->options().dynamic_list_cpp_new()
404 && (strprefix(demangled_name
, "operator new")
405 || strprefix(demangled_name
, "operator delete")))
407 free(demangled_name
);
410 else if (parameters
->options().dynamic_list_cpp_typeinfo()
411 && (strprefix(demangled_name
, "typeinfo name for")
412 || strprefix(demangled_name
, "typeinfo for")))
414 free(demangled_name
);
418 free(demangled_name
);
421 // If exporting all symbols or building a shared library,
422 // and the symbol is defined in a regular object and is
423 // externally visible, we need to add it.
424 if ((parameters
->options().export_dynamic() || parameters
->options().shared())
425 && !this->is_from_dynobj()
426 && !this->is_undefined()
427 && this->is_externally_visible())
433 // Return true if the final value of this symbol is known at link
437 Symbol::final_value_is_known() const
439 // If we are not generating an executable, then no final values are
440 // known, since they will change at runtime.
441 if (parameters
->options().output_is_position_independent()
442 || parameters
->options().relocatable())
445 // If the symbol is not from an object file, and is not undefined,
446 // then it is defined, and known.
447 if (this->source_
!= FROM_OBJECT
)
449 if (this->source_
!= IS_UNDEFINED
)
454 // If the symbol is from a dynamic object, then the final value
456 if (this->object()->is_dynamic())
459 // If the symbol is not undefined (it is defined or common),
460 // then the final value is known.
461 if (!this->is_undefined())
465 // If the symbol is undefined, then whether the final value is known
466 // depends on whether we are doing a static link. If we are doing a
467 // dynamic link, then the final value could be filled in at runtime.
468 // This could reasonably be the case for a weak undefined symbol.
469 return parameters
->doing_static_link();
472 // Return the output section where this symbol is defined.
475 Symbol::output_section() const
477 switch (this->source_
)
481 unsigned int shndx
= this->u_
.from_object
.shndx
;
482 if (shndx
!= elfcpp::SHN_UNDEF
&& this->is_ordinary_shndx_
)
484 gold_assert(!this->u_
.from_object
.object
->is_dynamic());
485 gold_assert(this->u_
.from_object
.object
->pluginobj() == NULL
);
486 Relobj
* relobj
= static_cast<Relobj
*>(this->u_
.from_object
.object
);
487 return relobj
->output_section(shndx
);
493 return this->u_
.in_output_data
.output_data
->output_section();
495 case IN_OUTPUT_SEGMENT
:
505 // Set the symbol's output section. This is used for symbols defined
506 // in scripts. This should only be called after the symbol table has
510 Symbol::set_output_section(Output_section
* os
)
512 switch (this->source_
)
516 gold_assert(this->output_section() == os
);
519 this->source_
= IN_OUTPUT_DATA
;
520 this->u_
.in_output_data
.output_data
= os
;
521 this->u_
.in_output_data
.offset_is_from_end
= false;
523 case IN_OUTPUT_SEGMENT
:
530 // Set the symbol's output segment. This is used for pre-defined
531 // symbols whose segments aren't known until after layout is done
532 // (e.g., __ehdr_start).
535 Symbol::set_output_segment(Output_segment
* os
, Segment_offset_base base
)
537 gold_assert(this->is_predefined_
);
538 this->source_
= IN_OUTPUT_SEGMENT
;
539 this->u_
.in_output_segment
.output_segment
= os
;
540 this->u_
.in_output_segment
.offset_base
= base
;
543 // Set the symbol to undefined. This is used for pre-defined
544 // symbols whose segments aren't known until after layout is done
545 // (e.g., __ehdr_start).
548 Symbol::set_undefined()
550 gold_assert(this->is_predefined_
);
551 this->source_
= IS_UNDEFINED
;
552 this->is_predefined_
= false;
555 // Class Symbol_table.
557 Symbol_table::Symbol_table(unsigned int count
,
558 const Version_script_info
& version_script
)
559 : saw_undefined_(0), offset_(0), table_(count
), namepool_(),
560 forwarders_(), commons_(), tls_commons_(), small_commons_(),
561 large_commons_(), forced_locals_(), warnings_(),
562 version_script_(version_script
), gc_(NULL
), icf_(NULL
)
564 namepool_
.reserve(count
);
567 Symbol_table::~Symbol_table()
571 // The symbol table key equality function. This is called with
575 Symbol_table::Symbol_table_eq::operator()(const Symbol_table_key
& k1
,
576 const Symbol_table_key
& k2
) const
578 return k1
.first
== k2
.first
&& k1
.second
== k2
.second
;
582 Symbol_table::is_section_folded(Object
* obj
, unsigned int shndx
) const
584 return (parameters
->options().icf_enabled()
585 && this->icf_
->is_section_folded(obj
, shndx
));
588 // For symbols that have been listed with a -u or --export-dynamic-symbol
589 // option, add them to the work list to avoid gc'ing them.
592 Symbol_table::gc_mark_undef_symbols(Layout
* layout
)
594 for (options::String_set::const_iterator p
=
595 parameters
->options().undefined_begin();
596 p
!= parameters
->options().undefined_end();
599 const char* name
= p
->c_str();
600 Symbol
* sym
= this->lookup(name
);
601 gold_assert(sym
!= NULL
);
602 if (sym
->source() == Symbol::FROM_OBJECT
603 && !sym
->object()->is_dynamic())
605 this->gc_mark_symbol(sym
);
609 for (options::String_set::const_iterator p
=
610 parameters
->options().export_dynamic_symbol_begin();
611 p
!= parameters
->options().export_dynamic_symbol_end();
614 const char* name
= p
->c_str();
615 Symbol
* sym
= this->lookup(name
);
616 // It's not an error if a symbol named by --export-dynamic-symbol
619 && sym
->source() == Symbol::FROM_OBJECT
620 && !sym
->object()->is_dynamic())
622 this->gc_mark_symbol(sym
);
626 for (Script_options::referenced_const_iterator p
=
627 layout
->script_options()->referenced_begin();
628 p
!= layout
->script_options()->referenced_end();
631 Symbol
* sym
= this->lookup(p
->c_str());
632 gold_assert(sym
!= NULL
);
633 if (sym
->source() == Symbol::FROM_OBJECT
634 && !sym
->object()->is_dynamic())
636 this->gc_mark_symbol(sym
);
642 Symbol_table::gc_mark_symbol(Symbol
* sym
)
644 // Add the object and section to the work list.
646 unsigned int shndx
= sym
->shndx(&is_ordinary
);
647 if (is_ordinary
&& shndx
!= elfcpp::SHN_UNDEF
)
649 gold_assert(this->gc_
!= NULL
);
650 this->gc_
->worklist().push(Section_id(sym
->object(), shndx
));
652 parameters
->target().gc_mark_symbol(this, sym
);
655 // When doing garbage collection, keep symbols that have been seen in
658 Symbol_table::gc_mark_dyn_syms(Symbol
* sym
)
660 if (sym
->in_dyn() && sym
->source() == Symbol::FROM_OBJECT
661 && !sym
->object()->is_dynamic())
662 this->gc_mark_symbol(sym
);
665 // Make TO a symbol which forwards to FROM.
668 Symbol_table::make_forwarder(Symbol
* from
, Symbol
* to
)
670 gold_assert(from
!= to
);
671 gold_assert(!from
->is_forwarder() && !to
->is_forwarder());
672 this->forwarders_
[from
] = to
;
673 from
->set_forwarder();
676 // Resolve the forwards from FROM, returning the real symbol.
679 Symbol_table::resolve_forwards(const Symbol
* from
) const
681 gold_assert(from
->is_forwarder());
682 Unordered_map
<const Symbol
*, Symbol
*>::const_iterator p
=
683 this->forwarders_
.find(from
);
684 gold_assert(p
!= this->forwarders_
.end());
688 // Look up a symbol by name.
691 Symbol_table::lookup(const char* name
, const char* version
) const
693 Stringpool::Key name_key
;
694 name
= this->namepool_
.find(name
, &name_key
);
698 Stringpool::Key version_key
= 0;
701 version
= this->namepool_
.find(version
, &version_key
);
706 Symbol_table_key
key(name_key
, version_key
);
707 Symbol_table::Symbol_table_type::const_iterator p
= this->table_
.find(key
);
708 if (p
== this->table_
.end())
713 // Resolve a Symbol with another Symbol. This is only used in the
714 // unusual case where there are references to both an unversioned
715 // symbol and a symbol with a version, and we then discover that that
716 // version is the default version. Because this is unusual, we do
717 // this the slow way, by converting back to an ELF symbol.
719 template<int size
, bool big_endian
>
721 Symbol_table::resolve(Sized_symbol
<size
>* to
, const Sized_symbol
<size
>* from
)
723 unsigned char buf
[elfcpp::Elf_sizes
<size
>::sym_size
];
724 elfcpp::Sym_write
<size
, big_endian
> esym(buf
);
725 // We don't bother to set the st_name or the st_shndx field.
726 esym
.put_st_value(from
->value());
727 esym
.put_st_size(from
->symsize());
728 esym
.put_st_info(from
->binding(), from
->type());
729 esym
.put_st_other(from
->visibility(), from
->nonvis());
731 unsigned int shndx
= from
->shndx(&is_ordinary
);
732 this->resolve(to
, esym
.sym(), shndx
, is_ordinary
, shndx
, from
->object(),
738 if (parameters
->options().gc_sections())
739 this->gc_mark_dyn_syms(to
);
742 // Record that a symbol is forced to be local by a version script or
746 Symbol_table::force_local(Symbol
* sym
)
748 if (!sym
->is_defined() && !sym
->is_common())
750 if (sym
->is_forced_local())
752 // We already got this one.
755 sym
->set_is_forced_local();
756 this->forced_locals_
.push_back(sym
);
759 // Adjust NAME for wrapping, and update *NAME_KEY if necessary. This
760 // is only called for undefined symbols, when at least one --wrap
764 Symbol_table::wrap_symbol(const char* name
, Stringpool::Key
* name_key
)
766 // For some targets, we need to ignore a specific character when
767 // wrapping, and add it back later.
769 if (name
[0] == parameters
->target().wrap_char())
775 if (parameters
->options().is_wrap(name
))
777 // Turn NAME into __wrap_NAME.
784 // This will give us both the old and new name in NAMEPOOL_, but
785 // that is OK. Only the versions we need will wind up in the
786 // real string table in the output file.
787 return this->namepool_
.add(s
.c_str(), true, name_key
);
790 const char* const real_prefix
= "__real_";
791 const size_t real_prefix_length
= strlen(real_prefix
);
792 if (strncmp(name
, real_prefix
, real_prefix_length
) == 0
793 && parameters
->options().is_wrap(name
+ real_prefix_length
))
795 // Turn __real_NAME into NAME.
799 s
+= name
+ real_prefix_length
;
800 return this->namepool_
.add(s
.c_str(), true, name_key
);
806 // This is called when we see a symbol NAME/VERSION, and the symbol
807 // already exists in the symbol table, and VERSION is marked as being
808 // the default version. SYM is the NAME/VERSION symbol we just added.
809 // DEFAULT_IS_NEW is true if this is the first time we have seen the
810 // symbol NAME/NULL. PDEF points to the entry for NAME/NULL.
812 template<int size
, bool big_endian
>
814 Symbol_table::define_default_version(Sized_symbol
<size
>* sym
,
816 Symbol_table_type::iterator pdef
)
820 // This is the first time we have seen NAME/NULL. Make
821 // NAME/NULL point to NAME/VERSION, and mark SYM as the default
824 sym
->set_is_default();
826 else if (pdef
->second
== sym
)
828 // NAME/NULL already points to NAME/VERSION. Don't mark the
829 // symbol as the default if it is not already the default.
833 // This is the unfortunate case where we already have entries
834 // for both NAME/VERSION and NAME/NULL. We now see a symbol
835 // NAME/VERSION where VERSION is the default version. We have
836 // already resolved this new symbol with the existing
837 // NAME/VERSION symbol.
839 // It's possible that NAME/NULL and NAME/VERSION are both
840 // defined in regular objects. This can only happen if one
841 // object file defines foo and another defines foo@@ver. This
842 // is somewhat obscure, but we call it a multiple definition
845 // It's possible that NAME/NULL actually has a version, in which
846 // case it won't be the same as VERSION. This happens with
847 // ver_test_7.so in the testsuite for the symbol t2_2. We see
848 // t2_2@@VER2, so we define both t2_2/VER2 and t2_2/NULL. We
849 // then see an unadorned t2_2 in an object file and give it
850 // version VER1 from the version script. This looks like a
851 // default definition for VER1, so it looks like we should merge
852 // t2_2/NULL with t2_2/VER1. That doesn't make sense, but it's
853 // not obvious that this is an error, either. So we just punt.
855 // If one of the symbols has non-default visibility, and the
856 // other is defined in a shared object, then they are different
859 // Otherwise, we just resolve the symbols as though they were
862 if (pdef
->second
->version() != NULL
)
863 gold_assert(pdef
->second
->version() != sym
->version());
864 else if (sym
->visibility() != elfcpp::STV_DEFAULT
865 && pdef
->second
->is_from_dynobj())
867 else if (pdef
->second
->visibility() != elfcpp::STV_DEFAULT
868 && sym
->is_from_dynobj())
872 const Sized_symbol
<size
>* symdef
;
873 symdef
= this->get_sized_symbol
<size
>(pdef
->second
);
874 Symbol_table::resolve
<size
, big_endian
>(sym
, symdef
);
875 this->make_forwarder(pdef
->second
, sym
);
877 sym
->set_is_default();
882 // Add one symbol from OBJECT to the symbol table. NAME is symbol
883 // name and VERSION is the version; both are canonicalized. DEF is
884 // whether this is the default version. ST_SHNDX is the symbol's
885 // section index; IS_ORDINARY is whether this is a normal section
886 // rather than a special code.
888 // If IS_DEFAULT_VERSION is true, then this is the definition of a
889 // default version of a symbol. That means that any lookup of
890 // NAME/NULL and any lookup of NAME/VERSION should always return the
891 // same symbol. This is obvious for references, but in particular we
892 // want to do this for definitions: overriding NAME/NULL should also
893 // override NAME/VERSION. If we don't do that, it would be very hard
894 // to override functions in a shared library which uses versioning.
896 // We implement this by simply making both entries in the hash table
897 // point to the same Symbol structure. That is easy enough if this is
898 // the first time we see NAME/NULL or NAME/VERSION, but it is possible
899 // that we have seen both already, in which case they will both have
900 // independent entries in the symbol table. We can't simply change
901 // the symbol table entry, because we have pointers to the entries
902 // attached to the object files. So we mark the entry attached to the
903 // object file as a forwarder, and record it in the forwarders_ map.
904 // Note that entries in the hash table will never be marked as
907 // ORIG_ST_SHNDX and ST_SHNDX are almost always the same.
908 // ORIG_ST_SHNDX is the section index in the input file, or SHN_UNDEF
909 // for a special section code. ST_SHNDX may be modified if the symbol
910 // is defined in a section being discarded.
912 template<int size
, bool big_endian
>
914 Symbol_table::add_from_object(Object
* object
,
916 Stringpool::Key name_key
,
918 Stringpool::Key version_key
,
919 bool is_default_version
,
920 const elfcpp::Sym
<size
, big_endian
>& sym
,
921 unsigned int st_shndx
,
923 unsigned int orig_st_shndx
)
925 // Print a message if this symbol is being traced.
926 if (parameters
->options().is_trace_symbol(name
))
928 if (orig_st_shndx
== elfcpp::SHN_UNDEF
)
929 gold_info(_("%s: reference to %s"), object
->name().c_str(), name
);
931 gold_info(_("%s: definition of %s"), object
->name().c_str(), name
);
934 // For an undefined symbol, we may need to adjust the name using
936 if (orig_st_shndx
== elfcpp::SHN_UNDEF
937 && parameters
->options().any_wrap())
939 const char* wrap_name
= this->wrap_symbol(name
, &name_key
);
940 if (wrap_name
!= name
)
942 // If we see a reference to malloc with version GLIBC_2.0,
943 // and we turn it into a reference to __wrap_malloc, then we
944 // discard the version number. Otherwise the user would be
945 // required to specify the correct version for
953 Symbol
* const snull
= NULL
;
954 std::pair
<typename
Symbol_table_type::iterator
, bool> ins
=
955 this->table_
.insert(std::make_pair(std::make_pair(name_key
, version_key
),
958 std::pair
<typename
Symbol_table_type::iterator
, bool> insdefault
=
959 std::make_pair(this->table_
.end(), false);
960 if (is_default_version
)
962 const Stringpool::Key vnull_key
= 0;
963 insdefault
= this->table_
.insert(std::make_pair(std::make_pair(name_key
,
968 // ins.first: an iterator, which is a pointer to a pair.
969 // ins.first->first: the key (a pair of name and version).
970 // ins.first->second: the value (Symbol*).
971 // ins.second: true if new entry was inserted, false if not.
973 Sized_symbol
<size
>* ret
;
978 // We already have an entry for NAME/VERSION.
979 ret
= this->get_sized_symbol
<size
>(ins
.first
->second
);
980 gold_assert(ret
!= NULL
);
982 was_undefined
= ret
->is_undefined();
983 // Commons from plugins are just placeholders.
984 was_common
= ret
->is_common() && ret
->object()->pluginobj() == NULL
;
986 this->resolve(ret
, sym
, st_shndx
, is_ordinary
, orig_st_shndx
, object
,
988 if (parameters
->options().gc_sections())
989 this->gc_mark_dyn_syms(ret
);
991 if (is_default_version
)
992 this->define_default_version
<size
, big_endian
>(ret
, insdefault
.second
,
997 // This is the first time we have seen NAME/VERSION.
998 gold_assert(ins
.first
->second
== NULL
);
1000 if (is_default_version
&& !insdefault
.second
)
1002 // We already have an entry for NAME/NULL. If we override
1003 // it, then change it to NAME/VERSION.
1004 ret
= this->get_sized_symbol
<size
>(insdefault
.first
->second
);
1006 was_undefined
= ret
->is_undefined();
1007 // Commons from plugins are just placeholders.
1008 was_common
= ret
->is_common() && ret
->object()->pluginobj() == NULL
;
1010 this->resolve(ret
, sym
, st_shndx
, is_ordinary
, orig_st_shndx
, object
,
1012 if (parameters
->options().gc_sections())
1013 this->gc_mark_dyn_syms(ret
);
1014 ins
.first
->second
= ret
;
1018 was_undefined
= false;
1021 Sized_target
<size
, big_endian
>* target
=
1022 parameters
->sized_target
<size
, big_endian
>();
1023 if (!target
->has_make_symbol())
1024 ret
= new Sized_symbol
<size
>();
1027 ret
= target
->make_symbol();
1030 // This means that we don't want a symbol table
1032 if (!is_default_version
)
1033 this->table_
.erase(ins
.first
);
1036 this->table_
.erase(insdefault
.first
);
1037 // Inserting INSDEFAULT invalidated INS.
1038 this->table_
.erase(std::make_pair(name_key
,
1045 ret
->init_object(name
, version
, object
, sym
, st_shndx
, is_ordinary
);
1047 ins
.first
->second
= ret
;
1048 if (is_default_version
)
1050 // This is the first time we have seen NAME/NULL. Point
1051 // it at the new entry for NAME/VERSION.
1052 gold_assert(insdefault
.second
);
1053 insdefault
.first
->second
= ret
;
1057 if (is_default_version
)
1058 ret
->set_is_default();
1061 // Record every time we see a new undefined symbol, to speed up
1063 if (!was_undefined
&& ret
->is_undefined())
1065 ++this->saw_undefined_
;
1066 if (parameters
->options().has_plugins())
1067 parameters
->options().plugins()->new_undefined_symbol(ret
);
1070 // Keep track of common symbols, to speed up common symbol
1071 // allocation. Don't record commons from plugin objects;
1072 // we need to wait until we see the real symbol in the
1073 // replacement file.
1074 if (!was_common
&& ret
->is_common() && ret
->object()->pluginobj() == NULL
)
1076 if (ret
->type() == elfcpp::STT_TLS
)
1077 this->tls_commons_
.push_back(ret
);
1078 else if (!is_ordinary
1079 && st_shndx
== parameters
->target().small_common_shndx())
1080 this->small_commons_
.push_back(ret
);
1081 else if (!is_ordinary
1082 && st_shndx
== parameters
->target().large_common_shndx())
1083 this->large_commons_
.push_back(ret
);
1085 this->commons_
.push_back(ret
);
1088 // If we're not doing a relocatable link, then any symbol with
1089 // hidden or internal visibility is local.
1090 if ((ret
->visibility() == elfcpp::STV_HIDDEN
1091 || ret
->visibility() == elfcpp::STV_INTERNAL
)
1092 && (ret
->binding() == elfcpp::STB_GLOBAL
1093 || ret
->binding() == elfcpp::STB_GNU_UNIQUE
1094 || ret
->binding() == elfcpp::STB_WEAK
)
1095 && !parameters
->options().relocatable())
1096 this->force_local(ret
);
1101 // Add all the symbols in a relocatable object to the hash table.
1103 template<int size
, bool big_endian
>
1105 Symbol_table::add_from_relobj(
1106 Sized_relobj_file
<size
, big_endian
>* relobj
,
1107 const unsigned char* syms
,
1109 size_t symndx_offset
,
1110 const char* sym_names
,
1111 size_t sym_name_size
,
1112 typename Sized_relobj_file
<size
, big_endian
>::Symbols
* sympointers
,
1117 gold_assert(size
== parameters
->target().get_size());
1119 const int sym_size
= elfcpp::Elf_sizes
<size
>::sym_size
;
1121 const bool just_symbols
= relobj
->just_symbols();
1123 const unsigned char* p
= syms
;
1124 for (size_t i
= 0; i
< count
; ++i
, p
+= sym_size
)
1126 (*sympointers
)[i
] = NULL
;
1128 elfcpp::Sym
<size
, big_endian
> sym(p
);
1130 unsigned int st_name
= sym
.get_st_name();
1131 if (st_name
>= sym_name_size
)
1133 relobj
->error(_("bad global symbol name offset %u at %zu"),
1138 const char* name
= sym_names
+ st_name
;
1140 if (strcmp (name
, "__gnu_lto_slim") == 0)
1141 gold_info(_("%s: plugin needed to handle lto object"),
1142 relobj
->name().c_str());
1145 unsigned int st_shndx
= relobj
->adjust_sym_shndx(i
+ symndx_offset
,
1148 unsigned int orig_st_shndx
= st_shndx
;
1150 orig_st_shndx
= elfcpp::SHN_UNDEF
;
1152 if (st_shndx
!= elfcpp::SHN_UNDEF
)
1155 // A symbol defined in a section which we are not including must
1156 // be treated as an undefined symbol.
1157 bool is_defined_in_discarded_section
= false;
1158 if (st_shndx
!= elfcpp::SHN_UNDEF
1160 && !relobj
->is_section_included(st_shndx
)
1161 && !this->is_section_folded(relobj
, st_shndx
))
1163 st_shndx
= elfcpp::SHN_UNDEF
;
1164 is_defined_in_discarded_section
= true;
1167 // In an object file, an '@' in the name separates the symbol
1168 // name from the version name. If there are two '@' characters,
1169 // this is the default version.
1170 const char* ver
= strchr(name
, '@');
1171 Stringpool::Key ver_key
= 0;
1173 // IS_DEFAULT_VERSION: is the version default?
1174 // IS_FORCED_LOCAL: is the symbol forced local?
1175 bool is_default_version
= false;
1176 bool is_forced_local
= false;
1178 // FIXME: For incremental links, we don't store version information,
1179 // so we need to ignore version symbols for now.
1180 if (parameters
->incremental_update() && ver
!= NULL
)
1182 namelen
= ver
- name
;
1188 // The symbol name is of the form foo@VERSION or foo@@VERSION
1189 namelen
= ver
- name
;
1193 is_default_version
= true;
1196 ver
= this->namepool_
.add(ver
, true, &ver_key
);
1198 // We don't want to assign a version to an undefined symbol,
1199 // even if it is listed in the version script. FIXME: What
1200 // about a common symbol?
1203 namelen
= strlen(name
);
1204 if (!this->version_script_
.empty()
1205 && st_shndx
!= elfcpp::SHN_UNDEF
)
1207 // The symbol name did not have a version, but the
1208 // version script may assign a version anyway.
1209 std::string version
;
1211 if (this->version_script_
.get_symbol_version(name
, &version
,
1215 is_forced_local
= true;
1216 else if (!version
.empty())
1218 ver
= this->namepool_
.add_with_length(version
.c_str(),
1222 is_default_version
= true;
1228 elfcpp::Sym
<size
, big_endian
>* psym
= &sym
;
1229 unsigned char symbuf
[sym_size
];
1230 elfcpp::Sym
<size
, big_endian
> sym2(symbuf
);
1233 memcpy(symbuf
, p
, sym_size
);
1234 elfcpp::Sym_write
<size
, big_endian
> sw(symbuf
);
1235 if (orig_st_shndx
!= elfcpp::SHN_UNDEF
1237 && relobj
->e_type() == elfcpp::ET_REL
)
1239 // Symbol values in relocatable object files are section
1240 // relative. This is normally what we want, but since here
1241 // we are converting the symbol to absolute we need to add
1242 // the section address. The section address in an object
1243 // file is normally zero, but people can use a linker
1244 // script to change it.
1245 sw
.put_st_value(sym
.get_st_value()
1246 + relobj
->section_address(orig_st_shndx
));
1248 st_shndx
= elfcpp::SHN_ABS
;
1249 is_ordinary
= false;
1253 // Fix up visibility if object has no-export set.
1254 if (relobj
->no_export()
1255 && (orig_st_shndx
!= elfcpp::SHN_UNDEF
|| !is_ordinary
))
1257 // We may have copied symbol already above.
1260 memcpy(symbuf
, p
, sym_size
);
1264 elfcpp::STV visibility
= sym2
.get_st_visibility();
1265 if (visibility
== elfcpp::STV_DEFAULT
1266 || visibility
== elfcpp::STV_PROTECTED
)
1268 elfcpp::Sym_write
<size
, big_endian
> sw(symbuf
);
1269 unsigned char nonvis
= sym2
.get_st_nonvis();
1270 sw
.put_st_other(elfcpp::STV_HIDDEN
, nonvis
);
1274 Stringpool::Key name_key
;
1275 name
= this->namepool_
.add_with_length(name
, namelen
, true,
1278 Sized_symbol
<size
>* res
;
1279 res
= this->add_from_object(relobj
, name
, name_key
, ver
, ver_key
,
1280 is_default_version
, *psym
, st_shndx
,
1281 is_ordinary
, orig_st_shndx
);
1283 if (is_forced_local
)
1284 this->force_local(res
);
1286 // Do not treat this symbol as garbage if this symbol will be
1287 // exported to the dynamic symbol table. This is true when
1288 // building a shared library or using --export-dynamic and
1289 // the symbol is externally visible.
1290 if (parameters
->options().gc_sections()
1291 && res
->is_externally_visible()
1292 && !res
->is_from_dynobj()
1293 && (parameters
->options().shared()
1294 || parameters
->options().export_dynamic()
1295 || parameters
->options().in_dynamic_list(res
->name())))
1296 this->gc_mark_symbol(res
);
1298 if (is_defined_in_discarded_section
)
1299 res
->set_is_defined_in_discarded_section();
1301 (*sympointers
)[i
] = res
;
1305 // Add a symbol from a plugin-claimed file.
1307 template<int size
, bool big_endian
>
1309 Symbol_table::add_from_pluginobj(
1310 Sized_pluginobj
<size
, big_endian
>* obj
,
1313 elfcpp::Sym
<size
, big_endian
>* sym
)
1315 unsigned int st_shndx
= sym
->get_st_shndx();
1316 bool is_ordinary
= st_shndx
< elfcpp::SHN_LORESERVE
;
1318 Stringpool::Key ver_key
= 0;
1319 bool is_default_version
= false;
1320 bool is_forced_local
= false;
1324 ver
= this->namepool_
.add(ver
, true, &ver_key
);
1326 // We don't want to assign a version to an undefined symbol,
1327 // even if it is listed in the version script. FIXME: What
1328 // about a common symbol?
1331 if (!this->version_script_
.empty()
1332 && st_shndx
!= elfcpp::SHN_UNDEF
)
1334 // The symbol name did not have a version, but the
1335 // version script may assign a version anyway.
1336 std::string version
;
1338 if (this->version_script_
.get_symbol_version(name
, &version
,
1342 is_forced_local
= true;
1343 else if (!version
.empty())
1345 ver
= this->namepool_
.add_with_length(version
.c_str(),
1349 is_default_version
= true;
1355 Stringpool::Key name_key
;
1356 name
= this->namepool_
.add(name
, true, &name_key
);
1358 Sized_symbol
<size
>* res
;
1359 res
= this->add_from_object(obj
, name
, name_key
, ver
, ver_key
,
1360 is_default_version
, *sym
, st_shndx
,
1361 is_ordinary
, st_shndx
);
1363 if (is_forced_local
)
1364 this->force_local(res
);
1369 // Add all the symbols in a dynamic object to the hash table.
1371 template<int size
, bool big_endian
>
1373 Symbol_table::add_from_dynobj(
1374 Sized_dynobj
<size
, big_endian
>* dynobj
,
1375 const unsigned char* syms
,
1377 const char* sym_names
,
1378 size_t sym_name_size
,
1379 const unsigned char* versym
,
1381 const std::vector
<const char*>* version_map
,
1382 typename Sized_relobj_file
<size
, big_endian
>::Symbols
* sympointers
,
1387 gold_assert(size
== parameters
->target().get_size());
1389 if (dynobj
->just_symbols())
1391 gold_error(_("--just-symbols does not make sense with a shared object"));
1395 // FIXME: For incremental links, we don't store version information,
1396 // so we need to ignore version symbols for now.
1397 if (parameters
->incremental_update())
1400 if (versym
!= NULL
&& versym_size
/ 2 < count
)
1402 dynobj
->error(_("too few symbol versions"));
1406 const int sym_size
= elfcpp::Elf_sizes
<size
>::sym_size
;
1408 // We keep a list of all STT_OBJECT symbols, so that we can resolve
1409 // weak aliases. This is necessary because if the dynamic object
1410 // provides the same variable under two names, one of which is a
1411 // weak definition, and the regular object refers to the weak
1412 // definition, we have to put both the weak definition and the
1413 // strong definition into the dynamic symbol table. Given a weak
1414 // definition, the only way that we can find the corresponding
1415 // strong definition, if any, is to search the symbol table.
1416 std::vector
<Sized_symbol
<size
>*> object_symbols
;
1418 const unsigned char* p
= syms
;
1419 const unsigned char* vs
= versym
;
1420 for (size_t i
= 0; i
< count
; ++i
, p
+= sym_size
, vs
+= 2)
1422 elfcpp::Sym
<size
, big_endian
> sym(p
);
1424 if (sympointers
!= NULL
)
1425 (*sympointers
)[i
] = NULL
;
1427 // Ignore symbols with local binding or that have
1428 // internal or hidden visibility.
1429 if (sym
.get_st_bind() == elfcpp::STB_LOCAL
1430 || sym
.get_st_visibility() == elfcpp::STV_INTERNAL
1431 || sym
.get_st_visibility() == elfcpp::STV_HIDDEN
)
1434 // A protected symbol in a shared library must be treated as a
1435 // normal symbol when viewed from outside the shared library.
1436 // Implement this by overriding the visibility here.
1437 elfcpp::Sym
<size
, big_endian
>* psym
= &sym
;
1438 unsigned char symbuf
[sym_size
];
1439 elfcpp::Sym
<size
, big_endian
> sym2(symbuf
);
1440 if (sym
.get_st_visibility() == elfcpp::STV_PROTECTED
)
1442 memcpy(symbuf
, p
, sym_size
);
1443 elfcpp::Sym_write
<size
, big_endian
> sw(symbuf
);
1444 sw
.put_st_other(elfcpp::STV_DEFAULT
, sym
.get_st_nonvis());
1448 unsigned int st_name
= psym
->get_st_name();
1449 if (st_name
>= sym_name_size
)
1451 dynobj
->error(_("bad symbol name offset %u at %zu"),
1456 const char* name
= sym_names
+ st_name
;
1459 unsigned int st_shndx
= dynobj
->adjust_sym_shndx(i
, psym
->get_st_shndx(),
1462 if (st_shndx
!= elfcpp::SHN_UNDEF
)
1465 Sized_symbol
<size
>* res
;
1469 Stringpool::Key name_key
;
1470 name
= this->namepool_
.add(name
, true, &name_key
);
1471 res
= this->add_from_object(dynobj
, name
, name_key
, NULL
, 0,
1472 false, *psym
, st_shndx
, is_ordinary
,
1477 // Read the version information.
1479 unsigned int v
= elfcpp::Swap
<16, big_endian
>::readval(vs
);
1481 bool hidden
= (v
& elfcpp::VERSYM_HIDDEN
) != 0;
1482 v
&= elfcpp::VERSYM_VERSION
;
1484 // The Sun documentation says that V can be VER_NDX_LOCAL,
1485 // or VER_NDX_GLOBAL, or a version index. The meaning of
1486 // VER_NDX_LOCAL is defined as "Symbol has local scope."
1487 // The old GNU linker will happily generate VER_NDX_LOCAL
1488 // for an undefined symbol. I don't know what the Sun
1489 // linker will generate.
1491 if (v
== static_cast<unsigned int>(elfcpp::VER_NDX_LOCAL
)
1492 && st_shndx
!= elfcpp::SHN_UNDEF
)
1494 // This symbol should not be visible outside the object.
1498 // At this point we are definitely going to add this symbol.
1499 Stringpool::Key name_key
;
1500 name
= this->namepool_
.add(name
, true, &name_key
);
1502 if (v
== static_cast<unsigned int>(elfcpp::VER_NDX_LOCAL
)
1503 || v
== static_cast<unsigned int>(elfcpp::VER_NDX_GLOBAL
))
1505 // This symbol does not have a version.
1506 res
= this->add_from_object(dynobj
, name
, name_key
, NULL
, 0,
1507 false, *psym
, st_shndx
, is_ordinary
,
1512 if (v
>= version_map
->size())
1514 dynobj
->error(_("versym for symbol %zu out of range: %u"),
1519 const char* version
= (*version_map
)[v
];
1520 if (version
== NULL
)
1522 dynobj
->error(_("versym for symbol %zu has no name: %u"),
1527 Stringpool::Key version_key
;
1528 version
= this->namepool_
.add(version
, true, &version_key
);
1530 // If this is an absolute symbol, and the version name
1531 // and symbol name are the same, then this is the
1532 // version definition symbol. These symbols exist to
1533 // support using -u to pull in particular versions. We
1534 // do not want to record a version for them.
1535 if (st_shndx
== elfcpp::SHN_ABS
1537 && name_key
== version_key
)
1538 res
= this->add_from_object(dynobj
, name
, name_key
, NULL
, 0,
1539 false, *psym
, st_shndx
, is_ordinary
,
1543 const bool is_default_version
=
1544 !hidden
&& st_shndx
!= elfcpp::SHN_UNDEF
;
1545 res
= this->add_from_object(dynobj
, name
, name_key
, version
,
1546 version_key
, is_default_version
,
1548 is_ordinary
, st_shndx
);
1553 // Note that it is possible that RES was overridden by an
1554 // earlier object, in which case it can't be aliased here.
1555 if (st_shndx
!= elfcpp::SHN_UNDEF
1557 && psym
->get_st_type() == elfcpp::STT_OBJECT
1558 && res
->source() == Symbol::FROM_OBJECT
1559 && res
->object() == dynobj
)
1560 object_symbols
.push_back(res
);
1562 if (sympointers
!= NULL
)
1563 (*sympointers
)[i
] = res
;
1566 this->record_weak_aliases(&object_symbols
);
1569 // Add a symbol from a incremental object file.
1571 template<int size
, bool big_endian
>
1573 Symbol_table::add_from_incrobj(
1577 elfcpp::Sym
<size
, big_endian
>* sym
)
1579 unsigned int st_shndx
= sym
->get_st_shndx();
1580 bool is_ordinary
= st_shndx
< elfcpp::SHN_LORESERVE
;
1582 Stringpool::Key ver_key
= 0;
1583 bool is_default_version
= false;
1584 bool is_forced_local
= false;
1586 Stringpool::Key name_key
;
1587 name
= this->namepool_
.add(name
, true, &name_key
);
1589 Sized_symbol
<size
>* res
;
1590 res
= this->add_from_object(obj
, name
, name_key
, ver
, ver_key
,
1591 is_default_version
, *sym
, st_shndx
,
1592 is_ordinary
, st_shndx
);
1594 if (is_forced_local
)
1595 this->force_local(res
);
1600 // This is used to sort weak aliases. We sort them first by section
1601 // index, then by offset, then by weak ahead of strong.
1604 class Weak_alias_sorter
1607 bool operator()(const Sized_symbol
<size
>*, const Sized_symbol
<size
>*) const;
1612 Weak_alias_sorter
<size
>::operator()(const Sized_symbol
<size
>* s1
,
1613 const Sized_symbol
<size
>* s2
) const
1616 unsigned int s1_shndx
= s1
->shndx(&is_ordinary
);
1617 gold_assert(is_ordinary
);
1618 unsigned int s2_shndx
= s2
->shndx(&is_ordinary
);
1619 gold_assert(is_ordinary
);
1620 if (s1_shndx
!= s2_shndx
)
1621 return s1_shndx
< s2_shndx
;
1623 if (s1
->value() != s2
->value())
1624 return s1
->value() < s2
->value();
1625 if (s1
->binding() != s2
->binding())
1627 if (s1
->binding() == elfcpp::STB_WEAK
)
1629 if (s2
->binding() == elfcpp::STB_WEAK
)
1632 return std::string(s1
->name()) < std::string(s2
->name());
1635 // SYMBOLS is a list of object symbols from a dynamic object. Look
1636 // for any weak aliases, and record them so that if we add the weak
1637 // alias to the dynamic symbol table, we also add the corresponding
1642 Symbol_table::record_weak_aliases(std::vector
<Sized_symbol
<size
>*>* symbols
)
1644 // Sort the vector by section index, then by offset, then by weak
1646 std::sort(symbols
->begin(), symbols
->end(), Weak_alias_sorter
<size
>());
1648 // Walk through the vector. For each weak definition, record
1650 for (typename
std::vector
<Sized_symbol
<size
>*>::const_iterator p
=
1652 p
!= symbols
->end();
1655 if ((*p
)->binding() != elfcpp::STB_WEAK
)
1658 // Build a circular list of weak aliases. Each symbol points to
1659 // the next one in the circular list.
1661 Sized_symbol
<size
>* from_sym
= *p
;
1662 typename
std::vector
<Sized_symbol
<size
>*>::const_iterator q
;
1663 for (q
= p
+ 1; q
!= symbols
->end(); ++q
)
1666 if ((*q
)->shndx(&dummy
) != from_sym
->shndx(&dummy
)
1667 || (*q
)->value() != from_sym
->value())
1670 this->weak_aliases_
[from_sym
] = *q
;
1671 from_sym
->set_has_alias();
1677 this->weak_aliases_
[from_sym
] = *p
;
1678 from_sym
->set_has_alias();
1685 // Create and return a specially defined symbol. If ONLY_IF_REF is
1686 // true, then only create the symbol if there is a reference to it.
1687 // If this does not return NULL, it sets *POLDSYM to the existing
1688 // symbol if there is one. This sets *RESOLVE_OLDSYM if we should
1689 // resolve the newly created symbol to the old one. This
1690 // canonicalizes *PNAME and *PVERSION.
1692 template<int size
, bool big_endian
>
1694 Symbol_table::define_special_symbol(const char** pname
, const char** pversion
,
1696 Sized_symbol
<size
>** poldsym
,
1697 bool* resolve_oldsym
)
1699 *resolve_oldsym
= false;
1702 // If the caller didn't give us a version, see if we get one from
1703 // the version script.
1705 bool is_default_version
= false;
1706 if (*pversion
== NULL
)
1709 if (this->version_script_
.get_symbol_version(*pname
, &v
, &is_global
))
1711 if (is_global
&& !v
.empty())
1713 *pversion
= v
.c_str();
1714 // If we get the version from a version script, then we
1715 // are also the default version.
1716 is_default_version
= true;
1722 Sized_symbol
<size
>* sym
;
1724 bool add_to_table
= false;
1725 typename
Symbol_table_type::iterator add_loc
= this->table_
.end();
1726 bool add_def_to_table
= false;
1727 typename
Symbol_table_type::iterator add_def_loc
= this->table_
.end();
1731 oldsym
= this->lookup(*pname
, *pversion
);
1732 if (oldsym
== NULL
&& is_default_version
)
1733 oldsym
= this->lookup(*pname
, NULL
);
1734 if (oldsym
== NULL
|| !oldsym
->is_undefined())
1737 *pname
= oldsym
->name();
1738 if (is_default_version
)
1739 *pversion
= this->namepool_
.add(*pversion
, true, NULL
);
1741 *pversion
= oldsym
->version();
1745 // Canonicalize NAME and VERSION.
1746 Stringpool::Key name_key
;
1747 *pname
= this->namepool_
.add(*pname
, true, &name_key
);
1749 Stringpool::Key version_key
= 0;
1750 if (*pversion
!= NULL
)
1751 *pversion
= this->namepool_
.add(*pversion
, true, &version_key
);
1753 Symbol
* const snull
= NULL
;
1754 std::pair
<typename
Symbol_table_type::iterator
, bool> ins
=
1755 this->table_
.insert(std::make_pair(std::make_pair(name_key
,
1759 std::pair
<typename
Symbol_table_type::iterator
, bool> insdefault
=
1760 std::make_pair(this->table_
.end(), false);
1761 if (is_default_version
)
1763 const Stringpool::Key vnull
= 0;
1765 this->table_
.insert(std::make_pair(std::make_pair(name_key
,
1772 // We already have a symbol table entry for NAME/VERSION.
1773 oldsym
= ins
.first
->second
;
1774 gold_assert(oldsym
!= NULL
);
1776 if (is_default_version
)
1778 Sized_symbol
<size
>* soldsym
=
1779 this->get_sized_symbol
<size
>(oldsym
);
1780 this->define_default_version
<size
, big_endian
>(soldsym
,
1787 // We haven't seen this symbol before.
1788 gold_assert(ins
.first
->second
== NULL
);
1790 add_to_table
= true;
1791 add_loc
= ins
.first
;
1793 if (is_default_version
&& !insdefault
.second
)
1795 // We are adding NAME/VERSION, and it is the default
1796 // version. We already have an entry for NAME/NULL.
1797 oldsym
= insdefault
.first
->second
;
1798 *resolve_oldsym
= true;
1804 if (is_default_version
)
1806 add_def_to_table
= true;
1807 add_def_loc
= insdefault
.first
;
1813 const Target
& target
= parameters
->target();
1814 if (!target
.has_make_symbol())
1815 sym
= new Sized_symbol
<size
>();
1818 Sized_target
<size
, big_endian
>* sized_target
=
1819 parameters
->sized_target
<size
, big_endian
>();
1820 sym
= sized_target
->make_symbol();
1826 add_loc
->second
= sym
;
1828 gold_assert(oldsym
!= NULL
);
1830 if (add_def_to_table
)
1831 add_def_loc
->second
= sym
;
1833 *poldsym
= this->get_sized_symbol
<size
>(oldsym
);
1838 // Define a symbol based on an Output_data.
1841 Symbol_table::define_in_output_data(const char* name
,
1842 const char* version
,
1848 elfcpp::STB binding
,
1849 elfcpp::STV visibility
,
1850 unsigned char nonvis
,
1851 bool offset_is_from_end
,
1854 if (parameters
->target().get_size() == 32)
1856 #if defined(HAVE_TARGET_32_LITTLE) || defined(HAVE_TARGET_32_BIG)
1857 return this->do_define_in_output_data
<32>(name
, version
, defined
, od
,
1858 value
, symsize
, type
, binding
,
1866 else if (parameters
->target().get_size() == 64)
1868 #if defined(HAVE_TARGET_64_LITTLE) || defined(HAVE_TARGET_64_BIG)
1869 return this->do_define_in_output_data
<64>(name
, version
, defined
, od
,
1870 value
, symsize
, type
, binding
,
1882 // Define a symbol in an Output_data, sized version.
1886 Symbol_table::do_define_in_output_data(
1888 const char* version
,
1891 typename
elfcpp::Elf_types
<size
>::Elf_Addr value
,
1892 typename
elfcpp::Elf_types
<size
>::Elf_WXword symsize
,
1894 elfcpp::STB binding
,
1895 elfcpp::STV visibility
,
1896 unsigned char nonvis
,
1897 bool offset_is_from_end
,
1900 Sized_symbol
<size
>* sym
;
1901 Sized_symbol
<size
>* oldsym
;
1902 bool resolve_oldsym
;
1904 if (parameters
->target().is_big_endian())
1906 #if defined(HAVE_TARGET_32_BIG) || defined(HAVE_TARGET_64_BIG)
1907 sym
= this->define_special_symbol
<size
, true>(&name
, &version
,
1908 only_if_ref
, &oldsym
,
1916 #if defined(HAVE_TARGET_32_LITTLE) || defined(HAVE_TARGET_64_LITTLE)
1917 sym
= this->define_special_symbol
<size
, false>(&name
, &version
,
1918 only_if_ref
, &oldsym
,
1928 sym
->init_output_data(name
, version
, od
, value
, symsize
, type
, binding
,
1929 visibility
, nonvis
, offset_is_from_end
,
1930 defined
== PREDEFINED
);
1934 if (binding
== elfcpp::STB_LOCAL
1935 || this->version_script_
.symbol_is_local(name
))
1936 this->force_local(sym
);
1937 else if (version
!= NULL
)
1938 sym
->set_is_default();
1942 if (Symbol_table::should_override_with_special(oldsym
, type
, defined
))
1943 this->override_with_special(oldsym
, sym
);
1954 // Define a symbol based on an Output_segment.
1957 Symbol_table::define_in_output_segment(const char* name
,
1958 const char* version
,
1964 elfcpp::STB binding
,
1965 elfcpp::STV visibility
,
1966 unsigned char nonvis
,
1967 Symbol::Segment_offset_base offset_base
,
1970 if (parameters
->target().get_size() == 32)
1972 #if defined(HAVE_TARGET_32_LITTLE) || defined(HAVE_TARGET_32_BIG)
1973 return this->do_define_in_output_segment
<32>(name
, version
, defined
, os
,
1974 value
, symsize
, type
,
1975 binding
, visibility
, nonvis
,
1976 offset_base
, only_if_ref
);
1981 else if (parameters
->target().get_size() == 64)
1983 #if defined(HAVE_TARGET_64_LITTLE) || defined(HAVE_TARGET_64_BIG)
1984 return this->do_define_in_output_segment
<64>(name
, version
, defined
, os
,
1985 value
, symsize
, type
,
1986 binding
, visibility
, nonvis
,
1987 offset_base
, only_if_ref
);
1996 // Define a symbol in an Output_segment, sized version.
2000 Symbol_table::do_define_in_output_segment(
2002 const char* version
,
2005 typename
elfcpp::Elf_types
<size
>::Elf_Addr value
,
2006 typename
elfcpp::Elf_types
<size
>::Elf_WXword symsize
,
2008 elfcpp::STB binding
,
2009 elfcpp::STV visibility
,
2010 unsigned char nonvis
,
2011 Symbol::Segment_offset_base offset_base
,
2014 Sized_symbol
<size
>* sym
;
2015 Sized_symbol
<size
>* oldsym
;
2016 bool resolve_oldsym
;
2018 if (parameters
->target().is_big_endian())
2020 #if defined(HAVE_TARGET_32_BIG) || defined(HAVE_TARGET_64_BIG)
2021 sym
= this->define_special_symbol
<size
, true>(&name
, &version
,
2022 only_if_ref
, &oldsym
,
2030 #if defined(HAVE_TARGET_32_LITTLE) || defined(HAVE_TARGET_64_LITTLE)
2031 sym
= this->define_special_symbol
<size
, false>(&name
, &version
,
2032 only_if_ref
, &oldsym
,
2042 sym
->init_output_segment(name
, version
, os
, value
, symsize
, type
, binding
,
2043 visibility
, nonvis
, offset_base
,
2044 defined
== PREDEFINED
);
2048 if (binding
== elfcpp::STB_LOCAL
2049 || this->version_script_
.symbol_is_local(name
))
2050 this->force_local(sym
);
2051 else if (version
!= NULL
)
2052 sym
->set_is_default();
2056 if (Symbol_table::should_override_with_special(oldsym
, type
, defined
))
2057 this->override_with_special(oldsym
, sym
);
2068 // Define a special symbol with a constant value. It is a multiple
2069 // definition error if this symbol is already defined.
2072 Symbol_table::define_as_constant(const char* name
,
2073 const char* version
,
2078 elfcpp::STB binding
,
2079 elfcpp::STV visibility
,
2080 unsigned char nonvis
,
2082 bool force_override
)
2084 if (parameters
->target().get_size() == 32)
2086 #if defined(HAVE_TARGET_32_LITTLE) || defined(HAVE_TARGET_32_BIG)
2087 return this->do_define_as_constant
<32>(name
, version
, defined
, value
,
2088 symsize
, type
, binding
,
2089 visibility
, nonvis
, only_if_ref
,
2095 else if (parameters
->target().get_size() == 64)
2097 #if defined(HAVE_TARGET_64_LITTLE) || defined(HAVE_TARGET_64_BIG)
2098 return this->do_define_as_constant
<64>(name
, version
, defined
, value
,
2099 symsize
, type
, binding
,
2100 visibility
, nonvis
, only_if_ref
,
2110 // Define a symbol as a constant, sized version.
2114 Symbol_table::do_define_as_constant(
2116 const char* version
,
2118 typename
elfcpp::Elf_types
<size
>::Elf_Addr value
,
2119 typename
elfcpp::Elf_types
<size
>::Elf_WXword symsize
,
2121 elfcpp::STB binding
,
2122 elfcpp::STV visibility
,
2123 unsigned char nonvis
,
2125 bool force_override
)
2127 Sized_symbol
<size
>* sym
;
2128 Sized_symbol
<size
>* oldsym
;
2129 bool resolve_oldsym
;
2131 if (parameters
->target().is_big_endian())
2133 #if defined(HAVE_TARGET_32_BIG) || defined(HAVE_TARGET_64_BIG)
2134 sym
= this->define_special_symbol
<size
, true>(&name
, &version
,
2135 only_if_ref
, &oldsym
,
2143 #if defined(HAVE_TARGET_32_LITTLE) || defined(HAVE_TARGET_64_LITTLE)
2144 sym
= this->define_special_symbol
<size
, false>(&name
, &version
,
2145 only_if_ref
, &oldsym
,
2155 sym
->init_constant(name
, version
, value
, symsize
, type
, binding
, visibility
,
2156 nonvis
, defined
== PREDEFINED
);
2160 // Version symbols are absolute symbols with name == version.
2161 // We don't want to force them to be local.
2162 if ((version
== NULL
2165 && (binding
== elfcpp::STB_LOCAL
2166 || this->version_script_
.symbol_is_local(name
)))
2167 this->force_local(sym
);
2168 else if (version
!= NULL
2169 && (name
!= version
|| value
!= 0))
2170 sym
->set_is_default();
2175 || Symbol_table::should_override_with_special(oldsym
, type
, defined
))
2176 this->override_with_special(oldsym
, sym
);
2187 // Define a set of symbols in output sections.
2190 Symbol_table::define_symbols(const Layout
* layout
, int count
,
2191 const Define_symbol_in_section
* p
,
2194 for (int i
= 0; i
< count
; ++i
, ++p
)
2196 Output_section
* os
= layout
->find_output_section(p
->output_section
);
2198 this->define_in_output_data(p
->name
, NULL
, PREDEFINED
, os
, p
->value
,
2199 p
->size
, p
->type
, p
->binding
,
2200 p
->visibility
, p
->nonvis
,
2201 p
->offset_is_from_end
,
2202 only_if_ref
|| p
->only_if_ref
);
2204 this->define_as_constant(p
->name
, NULL
, PREDEFINED
, 0, p
->size
,
2205 p
->type
, p
->binding
, p
->visibility
, p
->nonvis
,
2206 only_if_ref
|| p
->only_if_ref
,
2211 // Define a set of symbols in output segments.
2214 Symbol_table::define_symbols(const Layout
* layout
, int count
,
2215 const Define_symbol_in_segment
* p
,
2218 for (int i
= 0; i
< count
; ++i
, ++p
)
2220 Output_segment
* os
= layout
->find_output_segment(p
->segment_type
,
2221 p
->segment_flags_set
,
2222 p
->segment_flags_clear
);
2224 this->define_in_output_segment(p
->name
, NULL
, PREDEFINED
, os
, p
->value
,
2225 p
->size
, p
->type
, p
->binding
,
2226 p
->visibility
, p
->nonvis
,
2228 only_if_ref
|| p
->only_if_ref
);
2230 this->define_as_constant(p
->name
, NULL
, PREDEFINED
, 0, p
->size
,
2231 p
->type
, p
->binding
, p
->visibility
, p
->nonvis
,
2232 only_if_ref
|| p
->only_if_ref
,
2237 // Define CSYM using a COPY reloc. POSD is the Output_data where the
2238 // symbol should be defined--typically a .dyn.bss section. VALUE is
2239 // the offset within POSD.
2243 Symbol_table::define_with_copy_reloc(
2244 Sized_symbol
<size
>* csym
,
2246 typename
elfcpp::Elf_types
<size
>::Elf_Addr value
)
2248 gold_assert(csym
->is_from_dynobj());
2249 gold_assert(!csym
->is_copied_from_dynobj());
2250 Object
* object
= csym
->object();
2251 gold_assert(object
->is_dynamic());
2252 Dynobj
* dynobj
= static_cast<Dynobj
*>(object
);
2254 // Our copied variable has to override any variable in a shared
2256 elfcpp::STB binding
= csym
->binding();
2257 if (binding
== elfcpp::STB_WEAK
)
2258 binding
= elfcpp::STB_GLOBAL
;
2260 this->define_in_output_data(csym
->name(), csym
->version(), COPY
,
2261 posd
, value
, csym
->symsize(),
2262 csym
->type(), binding
,
2263 csym
->visibility(), csym
->nonvis(),
2266 csym
->set_is_copied_from_dynobj();
2267 csym
->set_needs_dynsym_entry();
2269 this->copied_symbol_dynobjs_
[csym
] = dynobj
;
2271 // We have now defined all aliases, but we have not entered them all
2272 // in the copied_symbol_dynobjs_ map.
2273 if (csym
->has_alias())
2278 sym
= this->weak_aliases_
[sym
];
2281 gold_assert(sym
->output_data() == posd
);
2283 sym
->set_is_copied_from_dynobj();
2284 this->copied_symbol_dynobjs_
[sym
] = dynobj
;
2289 // SYM is defined using a COPY reloc. Return the dynamic object where
2290 // the original definition was found.
2293 Symbol_table::get_copy_source(const Symbol
* sym
) const
2295 gold_assert(sym
->is_copied_from_dynobj());
2296 Copied_symbol_dynobjs::const_iterator p
=
2297 this->copied_symbol_dynobjs_
.find(sym
);
2298 gold_assert(p
!= this->copied_symbol_dynobjs_
.end());
2302 // Add any undefined symbols named on the command line.
2305 Symbol_table::add_undefined_symbols_from_command_line(Layout
* layout
)
2307 if (parameters
->options().any_undefined()
2308 || layout
->script_options()->any_unreferenced())
2310 if (parameters
->target().get_size() == 32)
2312 #if defined(HAVE_TARGET_32_LITTLE) || defined(HAVE_TARGET_32_BIG)
2313 this->do_add_undefined_symbols_from_command_line
<32>(layout
);
2318 else if (parameters
->target().get_size() == 64)
2320 #if defined(HAVE_TARGET_64_LITTLE) || defined(HAVE_TARGET_64_BIG)
2321 this->do_add_undefined_symbols_from_command_line
<64>(layout
);
2333 Symbol_table::do_add_undefined_symbols_from_command_line(Layout
* layout
)
2335 for (options::String_set::const_iterator p
=
2336 parameters
->options().undefined_begin();
2337 p
!= parameters
->options().undefined_end();
2339 this->add_undefined_symbol_from_command_line
<size
>(p
->c_str());
2341 for (options::String_set::const_iterator p
=
2342 parameters
->options().export_dynamic_symbol_begin();
2343 p
!= parameters
->options().export_dynamic_symbol_end();
2345 this->add_undefined_symbol_from_command_line
<size
>(p
->c_str());
2347 for (Script_options::referenced_const_iterator p
=
2348 layout
->script_options()->referenced_begin();
2349 p
!= layout
->script_options()->referenced_end();
2351 this->add_undefined_symbol_from_command_line
<size
>(p
->c_str());
2356 Symbol_table::add_undefined_symbol_from_command_line(const char* name
)
2358 if (this->lookup(name
) != NULL
)
2361 const char* version
= NULL
;
2363 Sized_symbol
<size
>* sym
;
2364 Sized_symbol
<size
>* oldsym
;
2365 bool resolve_oldsym
;
2366 if (parameters
->target().is_big_endian())
2368 #if defined(HAVE_TARGET_32_BIG) || defined(HAVE_TARGET_64_BIG)
2369 sym
= this->define_special_symbol
<size
, true>(&name
, &version
,
2378 #if defined(HAVE_TARGET_32_LITTLE) || defined(HAVE_TARGET_64_LITTLE)
2379 sym
= this->define_special_symbol
<size
, false>(&name
, &version
,
2387 gold_assert(oldsym
== NULL
);
2389 sym
->init_undefined(name
, version
, elfcpp::STT_NOTYPE
, elfcpp::STB_GLOBAL
,
2390 elfcpp::STV_DEFAULT
, 0);
2391 ++this->saw_undefined_
;
2394 // Set the dynamic symbol indexes. INDEX is the index of the first
2395 // global dynamic symbol. Pointers to the symbols are stored into the
2396 // vector SYMS. The names are added to DYNPOOL. This returns an
2397 // updated dynamic symbol index.
2400 Symbol_table::set_dynsym_indexes(unsigned int index
,
2401 std::vector
<Symbol
*>* syms
,
2402 Stringpool
* dynpool
,
2405 std::vector
<Symbol
*> as_needed_sym
;
2407 // Allow a target to set dynsym indexes.
2408 if (parameters
->target().has_custom_set_dynsym_indexes())
2410 std::vector
<Symbol
*> dyn_symbols
;
2411 for (Symbol_table_type::iterator p
= this->table_
.begin();
2412 p
!= this->table_
.end();
2415 Symbol
* sym
= p
->second
;
2416 if (!sym
->should_add_dynsym_entry(this))
2417 sym
->set_dynsym_index(-1U);
2419 dyn_symbols
.push_back(sym
);
2422 return parameters
->target().set_dynsym_indexes(&dyn_symbols
, index
, syms
,
2423 dynpool
, versions
, this);
2426 for (Symbol_table_type::iterator p
= this->table_
.begin();
2427 p
!= this->table_
.end();
2430 Symbol
* sym
= p
->second
;
2432 // Note that SYM may already have a dynamic symbol index, since
2433 // some symbols appear more than once in the symbol table, with
2434 // and without a version.
2436 if (!sym
->should_add_dynsym_entry(this))
2437 sym
->set_dynsym_index(-1U);
2438 else if (!sym
->has_dynsym_index())
2440 sym
->set_dynsym_index(index
);
2442 syms
->push_back(sym
);
2443 dynpool
->add(sym
->name(), false, NULL
);
2445 // If the symbol is defined in a dynamic object and is
2446 // referenced strongly in a regular object, then mark the
2447 // dynamic object as needed. This is used to implement
2449 if (sym
->is_from_dynobj()
2451 && !sym
->is_undef_binding_weak())
2452 sym
->object()->set_is_needed();
2454 // Record any version information, except those from
2455 // as-needed libraries not seen to be needed. Note that the
2456 // is_needed state for such libraries can change in this loop.
2457 if (sym
->version() != NULL
)
2459 if (!sym
->is_from_dynobj()
2460 || !sym
->object()->as_needed()
2461 || sym
->object()->is_needed())
2462 versions
->record_version(this, dynpool
, sym
);
2464 as_needed_sym
.push_back(sym
);
2469 // Process version information for symbols from as-needed libraries.
2470 for (std::vector
<Symbol
*>::iterator p
= as_needed_sym
.begin();
2471 p
!= as_needed_sym
.end();
2476 if (sym
->object()->is_needed())
2477 versions
->record_version(this, dynpool
, sym
);
2479 sym
->clear_version();
2482 // Finish up the versions. In some cases this may add new dynamic
2484 index
= versions
->finalize(this, index
, syms
);
2489 // Set the final values for all the symbols. The index of the first
2490 // global symbol in the output file is *PLOCAL_SYMCOUNT. Record the
2491 // file offset OFF. Add their names to POOL. Return the new file
2492 // offset. Update *PLOCAL_SYMCOUNT if necessary.
2495 Symbol_table::finalize(off_t off
, off_t dynoff
, size_t dyn_global_index
,
2496 size_t dyncount
, Stringpool
* pool
,
2497 unsigned int* plocal_symcount
)
2501 gold_assert(*plocal_symcount
!= 0);
2502 this->first_global_index_
= *plocal_symcount
;
2504 this->dynamic_offset_
= dynoff
;
2505 this->first_dynamic_global_index_
= dyn_global_index
;
2506 this->dynamic_count_
= dyncount
;
2508 if (parameters
->target().get_size() == 32)
2510 #if defined(HAVE_TARGET_32_BIG) || defined(HAVE_TARGET_32_LITTLE)
2511 ret
= this->sized_finalize
<32>(off
, pool
, plocal_symcount
);
2516 else if (parameters
->target().get_size() == 64)
2518 #if defined(HAVE_TARGET_64_BIG) || defined(HAVE_TARGET_64_LITTLE)
2519 ret
= this->sized_finalize
<64>(off
, pool
, plocal_symcount
);
2527 // Now that we have the final symbol table, we can reliably note
2528 // which symbols should get warnings.
2529 this->warnings_
.note_warnings(this);
2534 // SYM is going into the symbol table at *PINDEX. Add the name to
2535 // POOL, update *PINDEX and *POFF.
2539 Symbol_table::add_to_final_symtab(Symbol
* sym
, Stringpool
* pool
,
2540 unsigned int* pindex
, off_t
* poff
)
2542 sym
->set_symtab_index(*pindex
);
2543 if (sym
->version() == NULL
|| !parameters
->options().relocatable())
2544 pool
->add(sym
->name(), false, NULL
);
2546 pool
->add(sym
->versioned_name(), true, NULL
);
2548 *poff
+= elfcpp::Elf_sizes
<size
>::sym_size
;
2551 // Set the final value for all the symbols. This is called after
2552 // Layout::finalize, so all the output sections have their final
2557 Symbol_table::sized_finalize(off_t off
, Stringpool
* pool
,
2558 unsigned int* plocal_symcount
)
2560 off
= align_address(off
, size
>> 3);
2561 this->offset_
= off
;
2563 unsigned int index
= *plocal_symcount
;
2564 const unsigned int orig_index
= index
;
2566 // First do all the symbols which have been forced to be local, as
2567 // they must appear before all global symbols.
2568 for (Forced_locals::iterator p
= this->forced_locals_
.begin();
2569 p
!= this->forced_locals_
.end();
2573 gold_assert(sym
->is_forced_local());
2574 if (this->sized_finalize_symbol
<size
>(sym
))
2576 this->add_to_final_symtab
<size
>(sym
, pool
, &index
, &off
);
2581 // Now do all the remaining symbols.
2582 for (Symbol_table_type::iterator p
= this->table_
.begin();
2583 p
!= this->table_
.end();
2586 Symbol
* sym
= p
->second
;
2587 if (this->sized_finalize_symbol
<size
>(sym
))
2588 this->add_to_final_symtab
<size
>(sym
, pool
, &index
, &off
);
2591 this->output_count_
= index
- orig_index
;
2596 // Compute the final value of SYM and store status in location PSTATUS.
2597 // During relaxation, this may be called multiple times for a symbol to
2598 // compute its would-be final value in each relaxation pass.
2601 typename Sized_symbol
<size
>::Value_type
2602 Symbol_table::compute_final_value(
2603 const Sized_symbol
<size
>* sym
,
2604 Compute_final_value_status
* pstatus
) const
2606 typedef typename Sized_symbol
<size
>::Value_type Value_type
;
2609 switch (sym
->source())
2611 case Symbol::FROM_OBJECT
:
2614 unsigned int shndx
= sym
->shndx(&is_ordinary
);
2617 && shndx
!= elfcpp::SHN_ABS
2618 && !Symbol::is_common_shndx(shndx
))
2620 *pstatus
= CFVS_UNSUPPORTED_SYMBOL_SECTION
;
2624 Object
* symobj
= sym
->object();
2625 if (symobj
->is_dynamic())
2628 shndx
= elfcpp::SHN_UNDEF
;
2630 else if (symobj
->pluginobj() != NULL
)
2633 shndx
= elfcpp::SHN_UNDEF
;
2635 else if (shndx
== elfcpp::SHN_UNDEF
)
2637 else if (!is_ordinary
2638 && (shndx
== elfcpp::SHN_ABS
2639 || Symbol::is_common_shndx(shndx
)))
2640 value
= sym
->value();
2643 Relobj
* relobj
= static_cast<Relobj
*>(symobj
);
2644 Output_section
* os
= relobj
->output_section(shndx
);
2646 if (this->is_section_folded(relobj
, shndx
))
2648 gold_assert(os
== NULL
);
2649 // Get the os of the section it is folded onto.
2650 Section_id folded
= this->icf_
->get_folded_section(relobj
,
2652 gold_assert(folded
.first
!= NULL
);
2653 Relobj
* folded_obj
= reinterpret_cast<Relobj
*>(folded
.first
);
2654 unsigned folded_shndx
= folded
.second
;
2656 os
= folded_obj
->output_section(folded_shndx
);
2657 gold_assert(os
!= NULL
);
2659 // Replace (relobj, shndx) with canonical ICF input section.
2660 shndx
= folded_shndx
;
2661 relobj
= folded_obj
;
2664 uint64_t secoff64
= relobj
->output_section_offset(shndx
);
2667 bool static_or_reloc
= (parameters
->doing_static_link() ||
2668 parameters
->options().relocatable());
2669 gold_assert(static_or_reloc
|| sym
->dynsym_index() == -1U);
2671 *pstatus
= CFVS_NO_OUTPUT_SECTION
;
2675 if (secoff64
== -1ULL)
2677 // The section needs special handling (e.g., a merge section).
2679 value
= os
->output_address(relobj
, shndx
, sym
->value());
2684 convert_types
<Value_type
, uint64_t>(secoff64
);
2685 if (sym
->type() == elfcpp::STT_TLS
)
2686 value
= sym
->value() + os
->tls_offset() + secoff
;
2688 value
= sym
->value() + os
->address() + secoff
;
2694 case Symbol::IN_OUTPUT_DATA
:
2696 Output_data
* od
= sym
->output_data();
2697 value
= sym
->value();
2698 if (sym
->type() != elfcpp::STT_TLS
)
2699 value
+= od
->address();
2702 Output_section
* os
= od
->output_section();
2703 gold_assert(os
!= NULL
);
2704 value
+= os
->tls_offset() + (od
->address() - os
->address());
2706 if (sym
->offset_is_from_end())
2707 value
+= od
->data_size();
2711 case Symbol::IN_OUTPUT_SEGMENT
:
2713 Output_segment
* os
= sym
->output_segment();
2714 value
= sym
->value();
2715 if (sym
->type() != elfcpp::STT_TLS
)
2716 value
+= os
->vaddr();
2717 switch (sym
->offset_base())
2719 case Symbol::SEGMENT_START
:
2721 case Symbol::SEGMENT_END
:
2722 value
+= os
->memsz();
2724 case Symbol::SEGMENT_BSS
:
2725 value
+= os
->filesz();
2733 case Symbol::IS_CONSTANT
:
2734 value
= sym
->value();
2737 case Symbol::IS_UNDEFINED
:
2749 // Finalize the symbol SYM. This returns true if the symbol should be
2750 // added to the symbol table, false otherwise.
2754 Symbol_table::sized_finalize_symbol(Symbol
* unsized_sym
)
2756 typedef typename Sized_symbol
<size
>::Value_type Value_type
;
2758 Sized_symbol
<size
>* sym
= static_cast<Sized_symbol
<size
>*>(unsized_sym
);
2760 // The default version of a symbol may appear twice in the symbol
2761 // table. We only need to finalize it once.
2762 if (sym
->has_symtab_index())
2767 gold_assert(!sym
->has_symtab_index());
2768 sym
->set_symtab_index(-1U);
2769 gold_assert(sym
->dynsym_index() == -1U);
2773 // If the symbol is only present on plugin files, the plugin decided we
2775 if (!sym
->in_real_elf())
2777 gold_assert(!sym
->has_symtab_index());
2778 sym
->set_symtab_index(-1U);
2782 // Compute final symbol value.
2783 Compute_final_value_status status
;
2784 Value_type value
= this->compute_final_value(sym
, &status
);
2790 case CFVS_UNSUPPORTED_SYMBOL_SECTION
:
2793 unsigned int shndx
= sym
->shndx(&is_ordinary
);
2794 gold_error(_("%s: unsupported symbol section 0x%x"),
2795 sym
->demangled_name().c_str(), shndx
);
2798 case CFVS_NO_OUTPUT_SECTION
:
2799 sym
->set_symtab_index(-1U);
2805 sym
->set_value(value
);
2807 if (parameters
->options().strip_all()
2808 || !parameters
->options().should_retain_symbol(sym
->name()))
2810 sym
->set_symtab_index(-1U);
2817 // Write out the global symbols.
2820 Symbol_table::write_globals(const Stringpool
* sympool
,
2821 const Stringpool
* dynpool
,
2822 Output_symtab_xindex
* symtab_xindex
,
2823 Output_symtab_xindex
* dynsym_xindex
,
2824 Output_file
* of
) const
2826 switch (parameters
->size_and_endianness())
2828 #ifdef HAVE_TARGET_32_LITTLE
2829 case Parameters::TARGET_32_LITTLE
:
2830 this->sized_write_globals
<32, false>(sympool
, dynpool
, symtab_xindex
,
2834 #ifdef HAVE_TARGET_32_BIG
2835 case Parameters::TARGET_32_BIG
:
2836 this->sized_write_globals
<32, true>(sympool
, dynpool
, symtab_xindex
,
2840 #ifdef HAVE_TARGET_64_LITTLE
2841 case Parameters::TARGET_64_LITTLE
:
2842 this->sized_write_globals
<64, false>(sympool
, dynpool
, symtab_xindex
,
2846 #ifdef HAVE_TARGET_64_BIG
2847 case Parameters::TARGET_64_BIG
:
2848 this->sized_write_globals
<64, true>(sympool
, dynpool
, symtab_xindex
,
2857 // Write out the global symbols.
2859 template<int size
, bool big_endian
>
2861 Symbol_table::sized_write_globals(const Stringpool
* sympool
,
2862 const Stringpool
* dynpool
,
2863 Output_symtab_xindex
* symtab_xindex
,
2864 Output_symtab_xindex
* dynsym_xindex
,
2865 Output_file
* of
) const
2867 const Target
& target
= parameters
->target();
2869 const int sym_size
= elfcpp::Elf_sizes
<size
>::sym_size
;
2871 const unsigned int output_count
= this->output_count_
;
2872 const section_size_type oview_size
= output_count
* sym_size
;
2873 const unsigned int first_global_index
= this->first_global_index_
;
2874 unsigned char* psyms
;
2875 if (this->offset_
== 0 || output_count
== 0)
2878 psyms
= of
->get_output_view(this->offset_
, oview_size
);
2880 const unsigned int dynamic_count
= this->dynamic_count_
;
2881 const section_size_type dynamic_size
= dynamic_count
* sym_size
;
2882 const unsigned int first_dynamic_global_index
=
2883 this->first_dynamic_global_index_
;
2884 unsigned char* dynamic_view
;
2885 if (this->dynamic_offset_
== 0 || dynamic_count
== 0)
2886 dynamic_view
= NULL
;
2888 dynamic_view
= of
->get_output_view(this->dynamic_offset_
, dynamic_size
);
2890 for (Symbol_table_type::const_iterator p
= this->table_
.begin();
2891 p
!= this->table_
.end();
2894 Sized_symbol
<size
>* sym
= static_cast<Sized_symbol
<size
>*>(p
->second
);
2896 // Possibly warn about unresolved symbols in shared libraries.
2897 this->warn_about_undefined_dynobj_symbol(sym
);
2899 unsigned int sym_index
= sym
->symtab_index();
2900 unsigned int dynsym_index
;
2901 if (dynamic_view
== NULL
)
2904 dynsym_index
= sym
->dynsym_index();
2906 if (sym_index
== -1U && dynsym_index
== -1U)
2908 // This symbol is not included in the output file.
2913 typename
elfcpp::Elf_types
<size
>::Elf_Addr sym_value
= sym
->value();
2914 typename
elfcpp::Elf_types
<size
>::Elf_Addr dynsym_value
= sym_value
;
2915 elfcpp::STB binding
= sym
->binding();
2917 // If --no-gnu-unique is set, change STB_GNU_UNIQUE to STB_GLOBAL.
2918 if (binding
== elfcpp::STB_GNU_UNIQUE
2919 && !parameters
->options().gnu_unique())
2920 binding
= elfcpp::STB_GLOBAL
;
2922 switch (sym
->source())
2924 case Symbol::FROM_OBJECT
:
2927 unsigned int in_shndx
= sym
->shndx(&is_ordinary
);
2930 && in_shndx
!= elfcpp::SHN_ABS
2931 && !Symbol::is_common_shndx(in_shndx
))
2933 gold_error(_("%s: unsupported symbol section 0x%x"),
2934 sym
->demangled_name().c_str(), in_shndx
);
2939 Object
* symobj
= sym
->object();
2940 if (symobj
->is_dynamic())
2942 if (sym
->needs_dynsym_value())
2943 dynsym_value
= target
.dynsym_value(sym
);
2944 shndx
= elfcpp::SHN_UNDEF
;
2945 if (sym
->is_undef_binding_weak())
2946 binding
= elfcpp::STB_WEAK
;
2948 binding
= elfcpp::STB_GLOBAL
;
2950 else if (symobj
->pluginobj() != NULL
)
2951 shndx
= elfcpp::SHN_UNDEF
;
2952 else if (in_shndx
== elfcpp::SHN_UNDEF
2954 && (in_shndx
== elfcpp::SHN_ABS
2955 || Symbol::is_common_shndx(in_shndx
))))
2959 Relobj
* relobj
= static_cast<Relobj
*>(symobj
);
2960 Output_section
* os
= relobj
->output_section(in_shndx
);
2961 if (this->is_section_folded(relobj
, in_shndx
))
2963 // This global symbol must be written out even though
2965 // Get the os of the section it is folded onto.
2967 this->icf_
->get_folded_section(relobj
, in_shndx
);
2968 gold_assert(folded
.first
!=NULL
);
2969 Relobj
* folded_obj
=
2970 reinterpret_cast<Relobj
*>(folded
.first
);
2971 os
= folded_obj
->output_section(folded
.second
);
2972 gold_assert(os
!= NULL
);
2974 gold_assert(os
!= NULL
);
2975 shndx
= os
->out_shndx();
2977 if (shndx
>= elfcpp::SHN_LORESERVE
)
2979 if (sym_index
!= -1U)
2980 symtab_xindex
->add(sym_index
, shndx
);
2981 if (dynsym_index
!= -1U)
2982 dynsym_xindex
->add(dynsym_index
, shndx
);
2983 shndx
= elfcpp::SHN_XINDEX
;
2986 // In object files symbol values are section
2988 if (parameters
->options().relocatable())
2989 sym_value
-= os
->address();
2995 case Symbol::IN_OUTPUT_DATA
:
2997 Output_data
* od
= sym
->output_data();
2999 shndx
= od
->out_shndx();
3000 if (shndx
>= elfcpp::SHN_LORESERVE
)
3002 if (sym_index
!= -1U)
3003 symtab_xindex
->add(sym_index
, shndx
);
3004 if (dynsym_index
!= -1U)
3005 dynsym_xindex
->add(dynsym_index
, shndx
);
3006 shndx
= elfcpp::SHN_XINDEX
;
3009 // In object files symbol values are section
3011 if (parameters
->options().relocatable())
3012 sym_value
-= od
->address();
3016 case Symbol::IN_OUTPUT_SEGMENT
:
3017 shndx
= elfcpp::SHN_ABS
;
3020 case Symbol::IS_CONSTANT
:
3021 shndx
= elfcpp::SHN_ABS
;
3024 case Symbol::IS_UNDEFINED
:
3025 shndx
= elfcpp::SHN_UNDEF
;
3032 if (sym_index
!= -1U)
3034 sym_index
-= first_global_index
;
3035 gold_assert(sym_index
< output_count
);
3036 unsigned char* ps
= psyms
+ (sym_index
* sym_size
);
3037 this->sized_write_symbol
<size
, big_endian
>(sym
, sym_value
, shndx
,
3038 binding
, sympool
, ps
);
3041 if (dynsym_index
!= -1U)
3043 dynsym_index
-= first_dynamic_global_index
;
3044 gold_assert(dynsym_index
< dynamic_count
);
3045 unsigned char* pd
= dynamic_view
+ (dynsym_index
* sym_size
);
3046 this->sized_write_symbol
<size
, big_endian
>(sym
, dynsym_value
, shndx
,
3047 binding
, dynpool
, pd
);
3048 // Allow a target to adjust dynamic symbol value.
3049 parameters
->target().adjust_dyn_symbol(sym
, pd
);
3053 of
->write_output_view(this->offset_
, oview_size
, psyms
);
3054 if (dynamic_view
!= NULL
)
3055 of
->write_output_view(this->dynamic_offset_
, dynamic_size
, dynamic_view
);
3058 // Write out the symbol SYM, in section SHNDX, to P. POOL is the
3059 // strtab holding the name.
3061 template<int size
, bool big_endian
>
3063 Symbol_table::sized_write_symbol(
3064 Sized_symbol
<size
>* sym
,
3065 typename
elfcpp::Elf_types
<size
>::Elf_Addr value
,
3067 elfcpp::STB binding
,
3068 const Stringpool
* pool
,
3069 unsigned char* p
) const
3071 elfcpp::Sym_write
<size
, big_endian
> osym(p
);
3072 if (sym
->version() == NULL
|| !parameters
->options().relocatable())
3073 osym
.put_st_name(pool
->get_offset(sym
->name()));
3075 osym
.put_st_name(pool
->get_offset(sym
->versioned_name()));
3076 osym
.put_st_value(value
);
3077 // Use a symbol size of zero for undefined symbols from shared libraries.
3078 if (shndx
== elfcpp::SHN_UNDEF
&& sym
->is_from_dynobj())
3079 osym
.put_st_size(0);
3081 osym
.put_st_size(sym
->symsize());
3082 elfcpp::STT type
= sym
->type();
3083 // Turn IFUNC symbols from shared libraries into normal FUNC symbols.
3084 if (type
== elfcpp::STT_GNU_IFUNC
3085 && sym
->is_from_dynobj())
3086 type
= elfcpp::STT_FUNC
;
3087 // A version script may have overridden the default binding.
3088 if (sym
->is_forced_local())
3089 osym
.put_st_info(elfcpp::elf_st_info(elfcpp::STB_LOCAL
, type
));
3091 osym
.put_st_info(elfcpp::elf_st_info(binding
, type
));
3092 osym
.put_st_other(elfcpp::elf_st_other(sym
->visibility(), sym
->nonvis()));
3093 osym
.put_st_shndx(shndx
);
3096 // Check for unresolved symbols in shared libraries. This is
3097 // controlled by the --allow-shlib-undefined option.
3099 // We only warn about libraries for which we have seen all the
3100 // DT_NEEDED entries. We don't try to track down DT_NEEDED entries
3101 // which were not seen in this link. If we didn't see a DT_NEEDED
3102 // entry, we aren't going to be able to reliably report whether the
3103 // symbol is undefined.
3105 // We also don't warn about libraries found in a system library
3106 // directory (e.g., /lib or /usr/lib); we assume that those libraries
3107 // are OK. This heuristic avoids problems on GNU/Linux, in which -ldl
3108 // can have undefined references satisfied by ld-linux.so.
3111 Symbol_table::warn_about_undefined_dynobj_symbol(Symbol
* sym
) const
3114 if (sym
->source() == Symbol::FROM_OBJECT
3115 && sym
->object()->is_dynamic()
3116 && sym
->shndx(&dummy
) == elfcpp::SHN_UNDEF
3117 && sym
->binding() != elfcpp::STB_WEAK
3118 && !parameters
->options().allow_shlib_undefined()
3119 && !parameters
->target().is_defined_by_abi(sym
)
3120 && !sym
->object()->is_in_system_directory())
3122 // A very ugly cast.
3123 Dynobj
* dynobj
= static_cast<Dynobj
*>(sym
->object());
3124 if (!dynobj
->has_unknown_needed_entries())
3125 gold_undefined_symbol(sym
);
3129 // Write out a section symbol. Return the update offset.
3132 Symbol_table::write_section_symbol(const Output_section
* os
,
3133 Output_symtab_xindex
* symtab_xindex
,
3137 switch (parameters
->size_and_endianness())
3139 #ifdef HAVE_TARGET_32_LITTLE
3140 case Parameters::TARGET_32_LITTLE
:
3141 this->sized_write_section_symbol
<32, false>(os
, symtab_xindex
, of
,
3145 #ifdef HAVE_TARGET_32_BIG
3146 case Parameters::TARGET_32_BIG
:
3147 this->sized_write_section_symbol
<32, true>(os
, symtab_xindex
, of
,
3151 #ifdef HAVE_TARGET_64_LITTLE
3152 case Parameters::TARGET_64_LITTLE
:
3153 this->sized_write_section_symbol
<64, false>(os
, symtab_xindex
, of
,
3157 #ifdef HAVE_TARGET_64_BIG
3158 case Parameters::TARGET_64_BIG
:
3159 this->sized_write_section_symbol
<64, true>(os
, symtab_xindex
, of
,
3168 // Write out a section symbol, specialized for size and endianness.
3170 template<int size
, bool big_endian
>
3172 Symbol_table::sized_write_section_symbol(const Output_section
* os
,
3173 Output_symtab_xindex
* symtab_xindex
,
3177 const int sym_size
= elfcpp::Elf_sizes
<size
>::sym_size
;
3179 unsigned char* pov
= of
->get_output_view(offset
, sym_size
);
3181 elfcpp::Sym_write
<size
, big_endian
> osym(pov
);
3182 osym
.put_st_name(0);
3183 if (parameters
->options().relocatable())
3184 osym
.put_st_value(0);
3186 osym
.put_st_value(os
->address());
3187 osym
.put_st_size(0);
3188 osym
.put_st_info(elfcpp::elf_st_info(elfcpp::STB_LOCAL
,
3189 elfcpp::STT_SECTION
));
3190 osym
.put_st_other(elfcpp::elf_st_other(elfcpp::STV_DEFAULT
, 0));
3192 unsigned int shndx
= os
->out_shndx();
3193 if (shndx
>= elfcpp::SHN_LORESERVE
)
3195 symtab_xindex
->add(os
->symtab_index(), shndx
);
3196 shndx
= elfcpp::SHN_XINDEX
;
3198 osym
.put_st_shndx(shndx
);
3200 of
->write_output_view(offset
, sym_size
, pov
);
3203 // Print statistical information to stderr. This is used for --stats.
3206 Symbol_table::print_stats() const
3208 #if defined(HAVE_TR1_UNORDERED_MAP) || defined(HAVE_EXT_HASH_MAP)
3209 fprintf(stderr
, _("%s: symbol table entries: %zu; buckets: %zu\n"),
3210 program_name
, this->table_
.size(), this->table_
.bucket_count());
3212 fprintf(stderr
, _("%s: symbol table entries: %zu\n"),
3213 program_name
, this->table_
.size());
3215 this->namepool_
.print_stats("symbol table stringpool");
3218 // We check for ODR violations by looking for symbols with the same
3219 // name for which the debugging information reports that they were
3220 // defined in disjoint source locations. When comparing the source
3221 // location, we consider instances with the same base filename to be
3222 // the same. This is because different object files/shared libraries
3223 // can include the same header file using different paths, and
3224 // different optimization settings can make the line number appear to
3225 // be a couple lines off, and we don't want to report an ODR violation
3228 // This struct is used to compare line information, as returned by
3229 // Dwarf_line_info::one_addr2line. It implements a < comparison
3230 // operator used with std::sort.
3232 struct Odr_violation_compare
3235 operator()(const std::string
& s1
, const std::string
& s2
) const
3237 // Inputs should be of the form "dirname/filename:linenum" where
3238 // "dirname/" is optional. We want to compare just the filename:linenum.
3240 // Find the last '/' in each string.
3241 std::string::size_type s1begin
= s1
.rfind('/');
3242 std::string::size_type s2begin
= s2
.rfind('/');
3243 // If there was no '/' in a string, start at the beginning.
3244 if (s1begin
== std::string::npos
)
3246 if (s2begin
== std::string::npos
)
3248 return s1
.compare(s1begin
, std::string::npos
,
3249 s2
, s2begin
, std::string::npos
) < 0;
3253 // Returns all of the lines attached to LOC, not just the one the
3254 // instruction actually came from.
3255 std::vector
<std::string
>
3256 Symbol_table::linenos_from_loc(const Task
* task
,
3257 const Symbol_location
& loc
)
3259 // We need to lock the object in order to read it. This
3260 // means that we have to run in a singleton Task. If we
3261 // want to run this in a general Task for better
3262 // performance, we will need one Task for object, plus
3263 // appropriate locking to ensure that we don't conflict with
3264 // other uses of the object. Also note, one_addr2line is not
3265 // currently thread-safe.
3266 Task_lock_obj
<Object
> tl(task
, loc
.object
);
3268 std::vector
<std::string
> result
;
3269 Symbol_location code_loc
= loc
;
3270 parameters
->target().function_location(&code_loc
);
3271 // 16 is the size of the object-cache that one_addr2line should use.
3272 std::string canonical_result
= Dwarf_line_info::one_addr2line(
3273 code_loc
.object
, code_loc
.shndx
, code_loc
.offset
, 16, &result
);
3274 if (!canonical_result
.empty())
3275 result
.push_back(canonical_result
);
3279 // OutputIterator that records if it was ever assigned to. This
3280 // allows it to be used with std::set_intersection() to check for
3281 // intersection rather than computing the intersection.
3282 struct Check_intersection
3284 Check_intersection()
3288 bool had_intersection() const
3289 { return this->value_
; }
3291 Check_intersection
& operator++()
3294 Check_intersection
& operator*()
3297 template<typename T
>
3298 Check_intersection
& operator=(const T
&)
3300 this->value_
= true;
3308 // Check candidate_odr_violations_ to find symbols with the same name
3309 // but apparently different definitions (different source-file/line-no
3310 // for each line assigned to the first instruction).
3313 Symbol_table::detect_odr_violations(const Task
* task
,
3314 const char* output_file_name
) const
3316 for (Odr_map::const_iterator it
= candidate_odr_violations_
.begin();
3317 it
!= candidate_odr_violations_
.end();
3320 const char* const symbol_name
= it
->first
;
3322 std::string first_object_name
;
3323 std::vector
<std::string
> first_object_linenos
;
3325 Unordered_set
<Symbol_location
, Symbol_location_hash
>::const_iterator
3326 locs
= it
->second
.begin();
3327 const Unordered_set
<Symbol_location
, Symbol_location_hash
>::const_iterator
3328 locs_end
= it
->second
.end();
3329 for (; locs
!= locs_end
&& first_object_linenos
.empty(); ++locs
)
3331 // Save the line numbers from the first definition to
3332 // compare to the other definitions. Ideally, we'd compare
3333 // every definition to every other, but we don't want to
3334 // take O(N^2) time to do this. This shortcut may cause
3335 // false negatives that appear or disappear depending on the
3336 // link order, but it won't cause false positives.
3337 first_object_name
= locs
->object
->name();
3338 first_object_linenos
= this->linenos_from_loc(task
, *locs
);
3341 // Sort by Odr_violation_compare to make std::set_intersection work.
3342 std::sort(first_object_linenos
.begin(), first_object_linenos
.end(),
3343 Odr_violation_compare());
3345 for (; locs
!= locs_end
; ++locs
)
3347 std::vector
<std::string
> linenos
=
3348 this->linenos_from_loc(task
, *locs
);
3349 // linenos will be empty if we couldn't parse the debug info.
3350 if (linenos
.empty())
3352 // Sort by Odr_violation_compare to make std::set_intersection work.
3353 std::sort(linenos
.begin(), linenos
.end(), Odr_violation_compare());
3355 Check_intersection intersection_result
=
3356 std::set_intersection(first_object_linenos
.begin(),
3357 first_object_linenos
.end(),
3360 Check_intersection(),
3361 Odr_violation_compare());
3362 if (!intersection_result
.had_intersection())
3364 gold_warning(_("while linking %s: symbol '%s' defined in "
3365 "multiple places (possible ODR violation):"),
3366 output_file_name
, demangle(symbol_name
).c_str());
3367 // This only prints one location from each definition,
3368 // which may not be the location we expect to intersect
3369 // with another definition. We could print the whole
3370 // set of locations, but that seems too verbose.
3371 gold_assert(!first_object_linenos
.empty());
3372 gold_assert(!linenos
.empty());
3373 fprintf(stderr
, _(" %s from %s\n"),
3374 first_object_linenos
[0].c_str(),
3375 first_object_name
.c_str());
3376 fprintf(stderr
, _(" %s from %s\n"),
3378 locs
->object
->name().c_str());
3379 // Only print one broken pair, to avoid needing to
3380 // compare against a list of the disjoint definition
3381 // locations we've found so far. (If we kept comparing
3382 // against just the first one, we'd get a lot of
3383 // redundant complaints about the second definition
3389 // We only call one_addr2line() in this function, so we can clear its cache.
3390 Dwarf_line_info::clear_addr2line_cache();
3393 // Warnings functions.
3395 // Add a new warning.
3398 Warnings::add_warning(Symbol_table
* symtab
, const char* name
, Object
* obj
,
3399 const std::string
& warning
)
3401 name
= symtab
->canonicalize_name(name
);
3402 this->warnings_
[name
].set(obj
, warning
);
3405 // Look through the warnings and mark the symbols for which we should
3406 // warn. This is called during Layout::finalize when we know the
3407 // sources for all the symbols.
3410 Warnings::note_warnings(Symbol_table
* symtab
)
3412 for (Warning_table::iterator p
= this->warnings_
.begin();
3413 p
!= this->warnings_
.end();
3416 Symbol
* sym
= symtab
->lookup(p
->first
, NULL
);
3418 && sym
->source() == Symbol::FROM_OBJECT
3419 && sym
->object() == p
->second
.object
)
3420 sym
->set_has_warning();
3424 // Issue a warning. This is called when we see a relocation against a
3425 // symbol for which has a warning.
3427 template<int size
, bool big_endian
>
3429 Warnings::issue_warning(const Symbol
* sym
,
3430 const Relocate_info
<size
, big_endian
>* relinfo
,
3431 size_t relnum
, off_t reloffset
) const
3433 gold_assert(sym
->has_warning());
3435 // We don't want to issue a warning for a relocation against the
3436 // symbol in the same object file in which the symbol is defined.
3437 if (sym
->object() == relinfo
->object
)
3440 Warning_table::const_iterator p
= this->warnings_
.find(sym
->name());
3441 gold_assert(p
!= this->warnings_
.end());
3442 gold_warning_at_location(relinfo
, relnum
, reloffset
,
3443 "%s", p
->second
.text
.c_str());
3446 // Instantiate the templates we need. We could use the configure
3447 // script to restrict this to only the ones needed for implemented
3450 #if defined(HAVE_TARGET_32_LITTLE) || defined(HAVE_TARGET_32_BIG)
3453 Sized_symbol
<32>::allocate_common(Output_data
*, Value_type
);
3456 #if defined(HAVE_TARGET_64_LITTLE) || defined(HAVE_TARGET_64_BIG)
3459 Sized_symbol
<64>::allocate_common(Output_data
*, Value_type
);
3462 #ifdef HAVE_TARGET_32_LITTLE
3465 Symbol_table::add_from_relobj
<32, false>(
3466 Sized_relobj_file
<32, false>* relobj
,
3467 const unsigned char* syms
,
3469 size_t symndx_offset
,
3470 const char* sym_names
,
3471 size_t sym_name_size
,
3472 Sized_relobj_file
<32, false>::Symbols
* sympointers
,
3476 #ifdef HAVE_TARGET_32_BIG
3479 Symbol_table::add_from_relobj
<32, true>(
3480 Sized_relobj_file
<32, true>* relobj
,
3481 const unsigned char* syms
,
3483 size_t symndx_offset
,
3484 const char* sym_names
,
3485 size_t sym_name_size
,
3486 Sized_relobj_file
<32, true>::Symbols
* sympointers
,
3490 #ifdef HAVE_TARGET_64_LITTLE
3493 Symbol_table::add_from_relobj
<64, false>(
3494 Sized_relobj_file
<64, false>* relobj
,
3495 const unsigned char* syms
,
3497 size_t symndx_offset
,
3498 const char* sym_names
,
3499 size_t sym_name_size
,
3500 Sized_relobj_file
<64, false>::Symbols
* sympointers
,
3504 #ifdef HAVE_TARGET_64_BIG
3507 Symbol_table::add_from_relobj
<64, true>(
3508 Sized_relobj_file
<64, true>* relobj
,
3509 const unsigned char* syms
,
3511 size_t symndx_offset
,
3512 const char* sym_names
,
3513 size_t sym_name_size
,
3514 Sized_relobj_file
<64, true>::Symbols
* sympointers
,
3518 #ifdef HAVE_TARGET_32_LITTLE
3521 Symbol_table::add_from_pluginobj
<32, false>(
3522 Sized_pluginobj
<32, false>* obj
,
3525 elfcpp::Sym
<32, false>* sym
);
3528 #ifdef HAVE_TARGET_32_BIG
3531 Symbol_table::add_from_pluginobj
<32, true>(
3532 Sized_pluginobj
<32, true>* obj
,
3535 elfcpp::Sym
<32, true>* sym
);
3538 #ifdef HAVE_TARGET_64_LITTLE
3541 Symbol_table::add_from_pluginobj
<64, false>(
3542 Sized_pluginobj
<64, false>* obj
,
3545 elfcpp::Sym
<64, false>* sym
);
3548 #ifdef HAVE_TARGET_64_BIG
3551 Symbol_table::add_from_pluginobj
<64, true>(
3552 Sized_pluginobj
<64, true>* obj
,
3555 elfcpp::Sym
<64, true>* sym
);
3558 #ifdef HAVE_TARGET_32_LITTLE
3561 Symbol_table::add_from_dynobj
<32, false>(
3562 Sized_dynobj
<32, false>* dynobj
,
3563 const unsigned char* syms
,
3565 const char* sym_names
,
3566 size_t sym_name_size
,
3567 const unsigned char* versym
,
3569 const std::vector
<const char*>* version_map
,
3570 Sized_relobj_file
<32, false>::Symbols
* sympointers
,
3574 #ifdef HAVE_TARGET_32_BIG
3577 Symbol_table::add_from_dynobj
<32, true>(
3578 Sized_dynobj
<32, true>* dynobj
,
3579 const unsigned char* syms
,
3581 const char* sym_names
,
3582 size_t sym_name_size
,
3583 const unsigned char* versym
,
3585 const std::vector
<const char*>* version_map
,
3586 Sized_relobj_file
<32, true>::Symbols
* sympointers
,
3590 #ifdef HAVE_TARGET_64_LITTLE
3593 Symbol_table::add_from_dynobj
<64, false>(
3594 Sized_dynobj
<64, false>* dynobj
,
3595 const unsigned char* syms
,
3597 const char* sym_names
,
3598 size_t sym_name_size
,
3599 const unsigned char* versym
,
3601 const std::vector
<const char*>* version_map
,
3602 Sized_relobj_file
<64, false>::Symbols
* sympointers
,
3606 #ifdef HAVE_TARGET_64_BIG
3609 Symbol_table::add_from_dynobj
<64, true>(
3610 Sized_dynobj
<64, true>* dynobj
,
3611 const unsigned char* syms
,
3613 const char* sym_names
,
3614 size_t sym_name_size
,
3615 const unsigned char* versym
,
3617 const std::vector
<const char*>* version_map
,
3618 Sized_relobj_file
<64, true>::Symbols
* sympointers
,
3622 #ifdef HAVE_TARGET_32_LITTLE
3625 Symbol_table::add_from_incrobj(
3629 elfcpp::Sym
<32, false>* sym
);
3632 #ifdef HAVE_TARGET_32_BIG
3635 Symbol_table::add_from_incrobj(
3639 elfcpp::Sym
<32, true>* sym
);
3642 #ifdef HAVE_TARGET_64_LITTLE
3645 Symbol_table::add_from_incrobj(
3649 elfcpp::Sym
<64, false>* sym
);
3652 #ifdef HAVE_TARGET_64_BIG
3655 Symbol_table::add_from_incrobj(
3659 elfcpp::Sym
<64, true>* sym
);
3662 #if defined(HAVE_TARGET_32_LITTLE) || defined(HAVE_TARGET_32_BIG)
3665 Symbol_table::define_with_copy_reloc
<32>(
3666 Sized_symbol
<32>* sym
,
3668 elfcpp::Elf_types
<32>::Elf_Addr value
);
3671 #if defined(HAVE_TARGET_64_LITTLE) || defined(HAVE_TARGET_64_BIG)
3674 Symbol_table::define_with_copy_reloc
<64>(
3675 Sized_symbol
<64>* sym
,
3677 elfcpp::Elf_types
<64>::Elf_Addr value
);
3680 #if defined(HAVE_TARGET_32_LITTLE) || defined(HAVE_TARGET_32_BIG)
3683 Sized_symbol
<32>::init_output_data(const char* name
, const char* version
,
3684 Output_data
* od
, Value_type value
,
3685 Size_type symsize
, elfcpp::STT type
,
3686 elfcpp::STB binding
,
3687 elfcpp::STV visibility
,
3688 unsigned char nonvis
,
3689 bool offset_is_from_end
,
3690 bool is_predefined
);
3693 #if defined(HAVE_TARGET_64_LITTLE) || defined(HAVE_TARGET_64_BIG)
3696 Sized_symbol
<64>::init_output_data(const char* name
, const char* version
,
3697 Output_data
* od
, Value_type value
,
3698 Size_type symsize
, elfcpp::STT type
,
3699 elfcpp::STB binding
,
3700 elfcpp::STV visibility
,
3701 unsigned char nonvis
,
3702 bool offset_is_from_end
,
3703 bool is_predefined
);
3706 #ifdef HAVE_TARGET_32_LITTLE
3709 Warnings::issue_warning
<32, false>(const Symbol
* sym
,
3710 const Relocate_info
<32, false>* relinfo
,
3711 size_t relnum
, off_t reloffset
) const;
3714 #ifdef HAVE_TARGET_32_BIG
3717 Warnings::issue_warning
<32, true>(const Symbol
* sym
,
3718 const Relocate_info
<32, true>* relinfo
,
3719 size_t relnum
, off_t reloffset
) const;
3722 #ifdef HAVE_TARGET_64_LITTLE
3725 Warnings::issue_warning
<64, false>(const Symbol
* sym
,
3726 const Relocate_info
<64, false>* relinfo
,
3727 size_t relnum
, off_t reloffset
) const;
3730 #ifdef HAVE_TARGET_64_BIG
3733 Warnings::issue_warning
<64, true>(const Symbol
* sym
,
3734 const Relocate_info
<64, true>* relinfo
,
3735 size_t relnum
, off_t reloffset
) const;
3738 } // End namespace gold.