1 // symtab.cc -- the gold symbol table
3 // Copyright (C) 2006-2017 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
51 // u1_, u2_ and source_.
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;
83 this->is_protected_
= false;
84 this->non_zero_localentry_
= false;
87 // Return the demangled version of the symbol's name, but only
88 // if the --demangle flag was set.
91 demangle(const char* name
)
93 if (!parameters
->options().do_demangle())
96 // cplus_demangle allocates memory for the result it returns,
97 // and returns NULL if the name is already demangled.
98 char* demangled_name
= cplus_demangle(name
, DMGL_ANSI
| DMGL_PARAMS
);
99 if (demangled_name
== NULL
)
102 std::string
retval(demangled_name
);
103 free(demangled_name
);
108 Symbol::demangled_name() const
110 return demangle(this->name());
113 // Initialize the fields in the base class Symbol for SYM in OBJECT.
115 template<int size
, bool big_endian
>
117 Symbol::init_base_object(const char* name
, const char* version
, Object
* object
,
118 const elfcpp::Sym
<size
, big_endian
>& sym
,
119 unsigned int st_shndx
, bool is_ordinary
)
121 this->init_fields(name
, version
, sym
.get_st_type(), sym
.get_st_bind(),
122 sym
.get_st_visibility(), sym
.get_st_nonvis());
123 this->u1_
.object
= object
;
124 this->u2_
.shndx
= st_shndx
;
125 this->is_ordinary_shndx_
= is_ordinary
;
126 this->source_
= FROM_OBJECT
;
127 this->in_reg_
= !object
->is_dynamic();
128 this->in_dyn_
= object
->is_dynamic();
129 this->in_real_elf_
= object
->pluginobj() == NULL
;
132 // Initialize the fields in the base class Symbol for a symbol defined
133 // in an Output_data.
136 Symbol::init_base_output_data(const char* name
, const char* version
,
137 Output_data
* od
, elfcpp::STT type
,
138 elfcpp::STB binding
, elfcpp::STV visibility
,
139 unsigned char nonvis
, bool offset_is_from_end
,
142 this->init_fields(name
, version
, type
, binding
, visibility
, nonvis
);
143 this->u1_
.output_data
= od
;
144 this->u2_
.offset_is_from_end
= offset_is_from_end
;
145 this->source_
= IN_OUTPUT_DATA
;
146 this->in_reg_
= true;
147 this->in_real_elf_
= true;
148 this->is_predefined_
= is_predefined
;
151 // Initialize the fields in the base class Symbol for a symbol defined
152 // in an Output_segment.
155 Symbol::init_base_output_segment(const char* name
, const char* version
,
156 Output_segment
* os
, elfcpp::STT type
,
157 elfcpp::STB binding
, elfcpp::STV visibility
,
158 unsigned char nonvis
,
159 Segment_offset_base offset_base
,
162 this->init_fields(name
, version
, type
, binding
, visibility
, nonvis
);
163 this->u1_
.output_segment
= os
;
164 this->u2_
.offset_base
= offset_base
;
165 this->source_
= IN_OUTPUT_SEGMENT
;
166 this->in_reg_
= true;
167 this->in_real_elf_
= true;
168 this->is_predefined_
= is_predefined
;
171 // Initialize the fields in the base class Symbol for a symbol defined
175 Symbol::init_base_constant(const char* name
, const char* version
,
176 elfcpp::STT type
, elfcpp::STB binding
,
177 elfcpp::STV visibility
, unsigned char nonvis
,
180 this->init_fields(name
, version
, type
, binding
, visibility
, nonvis
);
181 this->source_
= IS_CONSTANT
;
182 this->in_reg_
= true;
183 this->in_real_elf_
= true;
184 this->is_predefined_
= is_predefined
;
187 // Initialize the fields in the base class Symbol for an undefined
191 Symbol::init_base_undefined(const char* name
, const char* version
,
192 elfcpp::STT type
, elfcpp::STB binding
,
193 elfcpp::STV visibility
, unsigned char nonvis
)
195 this->init_fields(name
, version
, type
, binding
, visibility
, nonvis
);
196 this->dynsym_index_
= -1U;
197 this->source_
= IS_UNDEFINED
;
198 this->in_reg_
= true;
199 this->in_real_elf_
= true;
202 // Allocate a common symbol in the base.
205 Symbol::allocate_base_common(Output_data
* od
)
207 gold_assert(this->is_common());
208 this->source_
= IN_OUTPUT_DATA
;
209 this->u1_
.output_data
= od
;
210 this->u2_
.offset_is_from_end
= false;
213 // Initialize the fields in Sized_symbol for SYM in OBJECT.
216 template<bool big_endian
>
218 Sized_symbol
<size
>::init_object(const char* name
, const char* version
,
220 const elfcpp::Sym
<size
, big_endian
>& sym
,
221 unsigned int st_shndx
, bool is_ordinary
)
223 this->init_base_object(name
, version
, object
, sym
, st_shndx
, is_ordinary
);
224 this->value_
= sym
.get_st_value();
225 this->symsize_
= sym
.get_st_size();
228 // Initialize the fields in Sized_symbol for a symbol defined in an
233 Sized_symbol
<size
>::init_output_data(const char* name
, const char* version
,
234 Output_data
* od
, Value_type value
,
235 Size_type symsize
, elfcpp::STT type
,
237 elfcpp::STV visibility
,
238 unsigned char nonvis
,
239 bool offset_is_from_end
,
242 this->init_base_output_data(name
, version
, od
, type
, binding
, visibility
,
243 nonvis
, offset_is_from_end
, is_predefined
);
244 this->value_
= value
;
245 this->symsize_
= symsize
;
248 // Initialize the fields in Sized_symbol for a symbol defined in an
253 Sized_symbol
<size
>::init_output_segment(const char* name
, const char* version
,
254 Output_segment
* os
, Value_type value
,
255 Size_type symsize
, elfcpp::STT type
,
257 elfcpp::STV visibility
,
258 unsigned char nonvis
,
259 Segment_offset_base offset_base
,
262 this->init_base_output_segment(name
, version
, os
, type
, binding
, visibility
,
263 nonvis
, offset_base
, is_predefined
);
264 this->value_
= value
;
265 this->symsize_
= symsize
;
268 // Initialize the fields in Sized_symbol for a symbol defined as a
273 Sized_symbol
<size
>::init_constant(const char* name
, const char* version
,
274 Value_type value
, Size_type symsize
,
275 elfcpp::STT type
, elfcpp::STB binding
,
276 elfcpp::STV visibility
, unsigned char nonvis
,
279 this->init_base_constant(name
, version
, type
, binding
, visibility
, nonvis
,
281 this->value_
= value
;
282 this->symsize_
= symsize
;
285 // Initialize the fields in Sized_symbol for an undefined symbol.
289 Sized_symbol
<size
>::init_undefined(const char* name
, const char* version
,
290 Value_type value
, elfcpp::STT type
,
291 elfcpp::STB binding
, elfcpp::STV visibility
,
292 unsigned char nonvis
)
294 this->init_base_undefined(name
, version
, type
, binding
, visibility
, nonvis
);
295 this->value_
= value
;
299 // Return an allocated string holding the symbol's name as
300 // name@version. This is used for relocatable links.
303 Symbol::versioned_name() const
305 gold_assert(this->version_
!= NULL
);
306 std::string ret
= this->name_
;
310 ret
+= this->version_
;
314 // Return true if SHNDX represents a common symbol.
317 Symbol::is_common_shndx(unsigned int shndx
)
319 return (shndx
== elfcpp::SHN_COMMON
320 || shndx
== parameters
->target().small_common_shndx()
321 || shndx
== parameters
->target().large_common_shndx());
324 // Allocate a common symbol.
328 Sized_symbol
<size
>::allocate_common(Output_data
* od
, Value_type value
)
330 this->allocate_base_common(od
);
331 this->value_
= value
;
334 // The ""'s around str ensure str is a string literal, so sizeof works.
335 #define strprefix(var, str) (strncmp(var, str, sizeof("" str "") - 1) == 0)
337 // Return true if this symbol should be added to the dynamic symbol
341 Symbol::should_add_dynsym_entry(Symbol_table
* symtab
) const
343 // If the symbol is only present on plugin files, the plugin decided we
345 if (!this->in_real_elf())
348 // If the symbol is used by a dynamic relocation, we need to add it.
349 if (this->needs_dynsym_entry())
352 // If this symbol's section is not added, the symbol need not be added.
353 // The section may have been GCed. Note that export_dynamic is being
354 // overridden here. This should not be done for shared objects.
355 if (parameters
->options().gc_sections()
356 && !parameters
->options().shared()
357 && this->source() == Symbol::FROM_OBJECT
358 && !this->object()->is_dynamic())
360 Relobj
* relobj
= static_cast<Relobj
*>(this->object());
362 unsigned int shndx
= this->shndx(&is_ordinary
);
363 if (is_ordinary
&& shndx
!= elfcpp::SHN_UNDEF
364 && !relobj
->is_section_included(shndx
)
365 && !symtab
->is_section_folded(relobj
, shndx
))
369 // If the symbol was forced dynamic in a --dynamic-list file
370 // or an --export-dynamic-symbol option, add it.
371 if (!this->is_from_dynobj()
372 && (parameters
->options().in_dynamic_list(this->name())
373 || parameters
->options().is_export_dynamic_symbol(this->name())))
375 if (!this->is_forced_local())
377 gold_warning(_("Cannot export local symbol '%s'"),
378 this->demangled_name().c_str());
382 // If the symbol was forced local in a version script, do not add it.
383 if (this->is_forced_local())
386 // If dynamic-list-data was specified, add any STT_OBJECT.
387 if (parameters
->options().dynamic_list_data()
388 && !this->is_from_dynobj()
389 && this->type() == elfcpp::STT_OBJECT
)
392 // If --dynamic-list-cpp-new was specified, add any new/delete symbol.
393 // If --dynamic-list-cpp-typeinfo was specified, add any typeinfo symbols.
394 if ((parameters
->options().dynamic_list_cpp_new()
395 || parameters
->options().dynamic_list_cpp_typeinfo())
396 && !this->is_from_dynobj())
398 // TODO(csilvers): We could probably figure out if we're an operator
399 // new/delete or typeinfo without the need to demangle.
400 char* demangled_name
= cplus_demangle(this->name(),
401 DMGL_ANSI
| DMGL_PARAMS
);
402 if (demangled_name
== NULL
)
404 // Not a C++ symbol, so it can't satisfy these flags
406 else if (parameters
->options().dynamic_list_cpp_new()
407 && (strprefix(demangled_name
, "operator new")
408 || strprefix(demangled_name
, "operator delete")))
410 free(demangled_name
);
413 else if (parameters
->options().dynamic_list_cpp_typeinfo()
414 && (strprefix(demangled_name
, "typeinfo name for")
415 || strprefix(demangled_name
, "typeinfo for")))
417 free(demangled_name
);
421 free(demangled_name
);
424 // If exporting all symbols or building a shared library,
425 // or the symbol should be globally unique (GNU_UNIQUE),
426 // and the symbol is defined in a regular object and is
427 // externally visible, we need to add it.
428 if ((parameters
->options().export_dynamic()
429 || parameters
->options().shared()
430 || (parameters
->options().gnu_unique()
431 && this->binding() == elfcpp::STB_GNU_UNIQUE
))
432 && !this->is_from_dynobj()
433 && !this->is_undefined()
434 && this->is_externally_visible())
440 // Return true if the final value of this symbol is known at link
444 Symbol::final_value_is_known() const
446 // If we are not generating an executable, then no final values are
447 // known, since they will change at runtime, with the exception of
448 // TLS symbols in a position-independent executable.
449 if ((parameters
->options().output_is_position_independent()
450 || parameters
->options().relocatable())
451 && !(this->type() == elfcpp::STT_TLS
452 && parameters
->options().pie()))
455 // If the symbol is not from an object file, and is not undefined,
456 // then it is defined, and known.
457 if (this->source_
!= FROM_OBJECT
)
459 if (this->source_
!= IS_UNDEFINED
)
464 // If the symbol is from a dynamic object, then the final value
466 if (this->object()->is_dynamic())
469 // If the symbol is not undefined (it is defined or common),
470 // then the final value is known.
471 if (!this->is_undefined())
475 // If the symbol is undefined, then whether the final value is known
476 // depends on whether we are doing a static link. If we are doing a
477 // dynamic link, then the final value could be filled in at runtime.
478 // This could reasonably be the case for a weak undefined symbol.
479 return parameters
->doing_static_link();
482 // Return the output section where this symbol is defined.
485 Symbol::output_section() const
487 switch (this->source_
)
491 unsigned int shndx
= this->u2_
.shndx
;
492 if (shndx
!= elfcpp::SHN_UNDEF
&& this->is_ordinary_shndx_
)
494 gold_assert(!this->u1_
.object
->is_dynamic());
495 gold_assert(this->u1_
.object
->pluginobj() == NULL
);
496 Relobj
* relobj
= static_cast<Relobj
*>(this->u1_
.object
);
497 return relobj
->output_section(shndx
);
503 return this->u1_
.output_data
->output_section();
505 case IN_OUTPUT_SEGMENT
:
515 // Set the symbol's output section. This is used for symbols defined
516 // in scripts. This should only be called after the symbol table has
520 Symbol::set_output_section(Output_section
* os
)
522 switch (this->source_
)
526 gold_assert(this->output_section() == os
);
529 this->source_
= IN_OUTPUT_DATA
;
530 this->u1_
.output_data
= os
;
531 this->u2_
.offset_is_from_end
= false;
533 case IN_OUTPUT_SEGMENT
:
540 // Set the symbol's output segment. This is used for pre-defined
541 // symbols whose segments aren't known until after layout is done
542 // (e.g., __ehdr_start).
545 Symbol::set_output_segment(Output_segment
* os
, Segment_offset_base base
)
547 gold_assert(this->is_predefined_
);
548 this->source_
= IN_OUTPUT_SEGMENT
;
549 this->u1_
.output_segment
= os
;
550 this->u2_
.offset_base
= base
;
553 // Set the symbol to undefined. This is used for pre-defined
554 // symbols whose segments aren't known until after layout is done
555 // (e.g., __ehdr_start).
558 Symbol::set_undefined()
560 this->source_
= IS_UNDEFINED
;
561 this->is_predefined_
= false;
564 // Class Symbol_table.
566 Symbol_table::Symbol_table(unsigned int count
,
567 const Version_script_info
& version_script
)
568 : saw_undefined_(0), offset_(0), table_(count
), namepool_(),
569 forwarders_(), commons_(), tls_commons_(), small_commons_(),
570 large_commons_(), forced_locals_(), warnings_(),
571 version_script_(version_script
), gc_(NULL
), icf_(NULL
),
574 namepool_
.reserve(count
);
577 Symbol_table::~Symbol_table()
581 // The symbol table key equality function. This is called with
585 Symbol_table::Symbol_table_eq::operator()(const Symbol_table_key
& k1
,
586 const Symbol_table_key
& k2
) const
588 return k1
.first
== k2
.first
&& k1
.second
== k2
.second
;
592 Symbol_table::is_section_folded(Relobj
* obj
, unsigned int shndx
) const
594 return (parameters
->options().icf_enabled()
595 && this->icf_
->is_section_folded(obj
, shndx
));
598 // For symbols that have been listed with a -u or --export-dynamic-symbol
599 // option, add them to the work list to avoid gc'ing them.
602 Symbol_table::gc_mark_undef_symbols(Layout
* layout
)
604 for (options::String_set::const_iterator p
=
605 parameters
->options().undefined_begin();
606 p
!= parameters
->options().undefined_end();
609 const char* name
= p
->c_str();
610 Symbol
* sym
= this->lookup(name
);
611 gold_assert(sym
!= NULL
);
612 if (sym
->source() == Symbol::FROM_OBJECT
613 && !sym
->object()->is_dynamic())
615 this->gc_mark_symbol(sym
);
619 for (options::String_set::const_iterator p
=
620 parameters
->options().export_dynamic_symbol_begin();
621 p
!= parameters
->options().export_dynamic_symbol_end();
624 const char* name
= p
->c_str();
625 Symbol
* sym
= this->lookup(name
);
626 // It's not an error if a symbol named by --export-dynamic-symbol
629 && sym
->source() == Symbol::FROM_OBJECT
630 && !sym
->object()->is_dynamic())
632 this->gc_mark_symbol(sym
);
636 for (Script_options::referenced_const_iterator p
=
637 layout
->script_options()->referenced_begin();
638 p
!= layout
->script_options()->referenced_end();
641 Symbol
* sym
= this->lookup(p
->c_str());
642 gold_assert(sym
!= NULL
);
643 if (sym
->source() == Symbol::FROM_OBJECT
644 && !sym
->object()->is_dynamic())
646 this->gc_mark_symbol(sym
);
652 Symbol_table::gc_mark_symbol(Symbol
* sym
)
654 // Add the object and section to the work list.
656 unsigned int shndx
= sym
->shndx(&is_ordinary
);
657 if (is_ordinary
&& shndx
!= elfcpp::SHN_UNDEF
&& !sym
->object()->is_dynamic())
659 gold_assert(this->gc_
!= NULL
);
660 Relobj
* relobj
= static_cast<Relobj
*>(sym
->object());
661 this->gc_
->worklist().push_back(Section_id(relobj
, shndx
));
663 parameters
->target().gc_mark_symbol(this, sym
);
666 // When doing garbage collection, keep symbols that have been seen in
669 Symbol_table::gc_mark_dyn_syms(Symbol
* sym
)
671 if (sym
->in_dyn() && sym
->source() == Symbol::FROM_OBJECT
672 && !sym
->object()->is_dynamic())
673 this->gc_mark_symbol(sym
);
676 // Make TO a symbol which forwards to FROM.
679 Symbol_table::make_forwarder(Symbol
* from
, Symbol
* to
)
681 gold_assert(from
!= to
);
682 gold_assert(!from
->is_forwarder() && !to
->is_forwarder());
683 this->forwarders_
[from
] = to
;
684 from
->set_forwarder();
687 // Resolve the forwards from FROM, returning the real symbol.
690 Symbol_table::resolve_forwards(const Symbol
* from
) const
692 gold_assert(from
->is_forwarder());
693 Unordered_map
<const Symbol
*, Symbol
*>::const_iterator p
=
694 this->forwarders_
.find(from
);
695 gold_assert(p
!= this->forwarders_
.end());
699 // Look up a symbol by name.
702 Symbol_table::lookup(const char* name
, const char* version
) const
704 Stringpool::Key name_key
;
705 name
= this->namepool_
.find(name
, &name_key
);
709 Stringpool::Key version_key
= 0;
712 version
= this->namepool_
.find(version
, &version_key
);
717 Symbol_table_key
key(name_key
, version_key
);
718 Symbol_table::Symbol_table_type::const_iterator p
= this->table_
.find(key
);
719 if (p
== this->table_
.end())
724 // Resolve a Symbol with another Symbol. This is only used in the
725 // unusual case where there are references to both an unversioned
726 // symbol and a symbol with a version, and we then discover that that
727 // version is the default version. Because this is unusual, we do
728 // this the slow way, by converting back to an ELF symbol.
730 template<int size
, bool big_endian
>
732 Symbol_table::resolve(Sized_symbol
<size
>* to
, const Sized_symbol
<size
>* from
)
734 unsigned char buf
[elfcpp::Elf_sizes
<size
>::sym_size
];
735 elfcpp::Sym_write
<size
, big_endian
> esym(buf
);
736 // We don't bother to set the st_name or the st_shndx field.
737 esym
.put_st_value(from
->value());
738 esym
.put_st_size(from
->symsize());
739 esym
.put_st_info(from
->binding(), from
->type());
740 esym
.put_st_other(from
->visibility(), from
->nonvis());
742 unsigned int shndx
= from
->shndx(&is_ordinary
);
743 this->resolve(to
, esym
.sym(), shndx
, is_ordinary
, shndx
, from
->object(),
744 from
->version(), true);
749 if (parameters
->options().gc_sections())
750 this->gc_mark_dyn_syms(to
);
753 // Record that a symbol is forced to be local by a version script or
757 Symbol_table::force_local(Symbol
* sym
)
759 if (!sym
->is_defined() && !sym
->is_common())
761 if (sym
->is_forced_local())
763 // We already got this one.
766 sym
->set_is_forced_local();
767 this->forced_locals_
.push_back(sym
);
770 // Adjust NAME for wrapping, and update *NAME_KEY if necessary. This
771 // is only called for undefined symbols, when at least one --wrap
775 Symbol_table::wrap_symbol(const char* name
, Stringpool::Key
* name_key
)
777 // For some targets, we need to ignore a specific character when
778 // wrapping, and add it back later.
780 if (name
[0] == parameters
->target().wrap_char())
786 if (parameters
->options().is_wrap(name
))
788 // Turn NAME into __wrap_NAME.
795 // This will give us both the old and new name in NAMEPOOL_, but
796 // that is OK. Only the versions we need will wind up in the
797 // real string table in the output file.
798 return this->namepool_
.add(s
.c_str(), true, name_key
);
801 const char* const real_prefix
= "__real_";
802 const size_t real_prefix_length
= strlen(real_prefix
);
803 if (strncmp(name
, real_prefix
, real_prefix_length
) == 0
804 && parameters
->options().is_wrap(name
+ real_prefix_length
))
806 // Turn __real_NAME into NAME.
810 s
+= name
+ real_prefix_length
;
811 return this->namepool_
.add(s
.c_str(), true, name_key
);
817 // This is called when we see a symbol NAME/VERSION, and the symbol
818 // already exists in the symbol table, and VERSION is marked as being
819 // the default version. SYM is the NAME/VERSION symbol we just added.
820 // DEFAULT_IS_NEW is true if this is the first time we have seen the
821 // symbol NAME/NULL. PDEF points to the entry for NAME/NULL.
823 template<int size
, bool big_endian
>
825 Symbol_table::define_default_version(Sized_symbol
<size
>* sym
,
827 Symbol_table_type::iterator pdef
)
831 // This is the first time we have seen NAME/NULL. Make
832 // NAME/NULL point to NAME/VERSION, and mark SYM as the default
835 sym
->set_is_default();
837 else if (pdef
->second
== sym
)
839 // NAME/NULL already points to NAME/VERSION. Don't mark the
840 // symbol as the default if it is not already the default.
844 // This is the unfortunate case where we already have entries
845 // for both NAME/VERSION and NAME/NULL. We now see a symbol
846 // NAME/VERSION where VERSION is the default version. We have
847 // already resolved this new symbol with the existing
848 // NAME/VERSION symbol.
850 // It's possible that NAME/NULL and NAME/VERSION are both
851 // defined in regular objects. This can only happen if one
852 // object file defines foo and another defines foo@@ver. This
853 // is somewhat obscure, but we call it a multiple definition
856 // It's possible that NAME/NULL actually has a version, in which
857 // case it won't be the same as VERSION. This happens with
858 // ver_test_7.so in the testsuite for the symbol t2_2. We see
859 // t2_2@@VER2, so we define both t2_2/VER2 and t2_2/NULL. We
860 // then see an unadorned t2_2 in an object file and give it
861 // version VER1 from the version script. This looks like a
862 // default definition for VER1, so it looks like we should merge
863 // t2_2/NULL with t2_2/VER1. That doesn't make sense, but it's
864 // not obvious that this is an error, either. So we just punt.
866 // If one of the symbols has non-default visibility, and the
867 // other is defined in a shared object, then they are different
870 // If the two symbols are from different shared objects,
871 // they are different symbols.
873 // Otherwise, we just resolve the symbols as though they were
876 if (pdef
->second
->version() != NULL
)
877 gold_assert(pdef
->second
->version() != sym
->version());
878 else if (sym
->visibility() != elfcpp::STV_DEFAULT
879 && pdef
->second
->is_from_dynobj())
881 else if (pdef
->second
->visibility() != elfcpp::STV_DEFAULT
882 && sym
->is_from_dynobj())
884 else if (pdef
->second
->is_from_dynobj()
885 && sym
->is_from_dynobj()
886 && pdef
->second
->is_defined()
887 && pdef
->second
->object() != sym
->object())
891 const Sized_symbol
<size
>* symdef
;
892 symdef
= this->get_sized_symbol
<size
>(pdef
->second
);
893 Symbol_table::resolve
<size
, big_endian
>(sym
, symdef
);
894 this->make_forwarder(pdef
->second
, sym
);
896 sym
->set_is_default();
901 // Add one symbol from OBJECT to the symbol table. NAME is symbol
902 // name and VERSION is the version; both are canonicalized. DEF is
903 // whether this is the default version. ST_SHNDX is the symbol's
904 // section index; IS_ORDINARY is whether this is a normal section
905 // rather than a special code.
907 // If IS_DEFAULT_VERSION is true, then this is the definition of a
908 // default version of a symbol. That means that any lookup of
909 // NAME/NULL and any lookup of NAME/VERSION should always return the
910 // same symbol. This is obvious for references, but in particular we
911 // want to do this for definitions: overriding NAME/NULL should also
912 // override NAME/VERSION. If we don't do that, it would be very hard
913 // to override functions in a shared library which uses versioning.
915 // We implement this by simply making both entries in the hash table
916 // point to the same Symbol structure. That is easy enough if this is
917 // the first time we see NAME/NULL or NAME/VERSION, but it is possible
918 // that we have seen both already, in which case they will both have
919 // independent entries in the symbol table. We can't simply change
920 // the symbol table entry, because we have pointers to the entries
921 // attached to the object files. So we mark the entry attached to the
922 // object file as a forwarder, and record it in the forwarders_ map.
923 // Note that entries in the hash table will never be marked as
926 // ORIG_ST_SHNDX and ST_SHNDX are almost always the same.
927 // ORIG_ST_SHNDX is the section index in the input file, or SHN_UNDEF
928 // for a special section code. ST_SHNDX may be modified if the symbol
929 // is defined in a section being discarded.
931 template<int size
, bool big_endian
>
933 Symbol_table::add_from_object(Object
* object
,
935 Stringpool::Key name_key
,
937 Stringpool::Key version_key
,
938 bool is_default_version
,
939 const elfcpp::Sym
<size
, big_endian
>& sym
,
940 unsigned int st_shndx
,
942 unsigned int orig_st_shndx
)
944 // Print a message if this symbol is being traced.
945 if (parameters
->options().is_trace_symbol(name
))
947 if (orig_st_shndx
== elfcpp::SHN_UNDEF
)
948 gold_info(_("%s: reference to %s"), object
->name().c_str(), name
);
950 gold_info(_("%s: definition of %s"), object
->name().c_str(), name
);
953 // For an undefined symbol, we may need to adjust the name using
955 if (orig_st_shndx
== elfcpp::SHN_UNDEF
956 && parameters
->options().any_wrap())
958 const char* wrap_name
= this->wrap_symbol(name
, &name_key
);
959 if (wrap_name
!= name
)
961 // If we see a reference to malloc with version GLIBC_2.0,
962 // and we turn it into a reference to __wrap_malloc, then we
963 // discard the version number. Otherwise the user would be
964 // required to specify the correct version for
972 Symbol
* const snull
= NULL
;
973 std::pair
<typename
Symbol_table_type::iterator
, bool> ins
=
974 this->table_
.insert(std::make_pair(std::make_pair(name_key
, version_key
),
977 std::pair
<typename
Symbol_table_type::iterator
, bool> insdefault
=
978 std::make_pair(this->table_
.end(), false);
979 if (is_default_version
)
981 const Stringpool::Key vnull_key
= 0;
982 insdefault
= this->table_
.insert(std::make_pair(std::make_pair(name_key
,
987 // ins.first: an iterator, which is a pointer to a pair.
988 // ins.first->first: the key (a pair of name and version).
989 // ins.first->second: the value (Symbol*).
990 // ins.second: true if new entry was inserted, false if not.
992 Sized_symbol
<size
>* ret
;
997 // We already have an entry for NAME/VERSION.
998 ret
= this->get_sized_symbol
<size
>(ins
.first
->second
);
999 gold_assert(ret
!= NULL
);
1001 was_undefined
= ret
->is_undefined();
1002 // Commons from plugins are just placeholders.
1003 was_common
= ret
->is_common() && ret
->object()->pluginobj() == NULL
;
1005 this->resolve(ret
, sym
, st_shndx
, is_ordinary
, orig_st_shndx
, object
,
1006 version
, is_default_version
);
1007 if (parameters
->options().gc_sections())
1008 this->gc_mark_dyn_syms(ret
);
1010 if (is_default_version
)
1011 this->define_default_version
<size
, big_endian
>(ret
, insdefault
.second
,
1017 && ret
->source() == Symbol::FROM_OBJECT
1018 && ret
->object() == object
1020 && ret
->shndx(&dummy
) == st_shndx
1021 && ret
->is_default())
1023 // We have seen NAME/VERSION already, and marked it as the
1024 // default version, but now we see a definition for
1025 // NAME/VERSION that is not the default version. This can
1026 // happen when the assembler generates two symbols for
1027 // a symbol as a result of a ".symver foo,foo@VER"
1028 // directive. We see the first unversioned symbol and
1029 // we may mark it as the default version (from a
1030 // version script); then we see the second versioned
1031 // symbol and we need to override the first.
1032 // In any other case, the two symbols should have generated
1033 // a multiple definition error.
1034 // (See PR gold/18703.)
1035 ret
->set_is_not_default();
1036 const Stringpool::Key vnull_key
= 0;
1037 this->table_
.erase(std::make_pair(name_key
, vnull_key
));
1043 // This is the first time we have seen NAME/VERSION.
1044 gold_assert(ins
.first
->second
== NULL
);
1046 if (is_default_version
&& !insdefault
.second
)
1048 // We already have an entry for NAME/NULL. If we override
1049 // it, then change it to NAME/VERSION.
1050 ret
= this->get_sized_symbol
<size
>(insdefault
.first
->second
);
1052 was_undefined
= ret
->is_undefined();
1053 // Commons from plugins are just placeholders.
1054 was_common
= ret
->is_common() && ret
->object()->pluginobj() == NULL
;
1056 this->resolve(ret
, sym
, st_shndx
, is_ordinary
, orig_st_shndx
, object
,
1057 version
, is_default_version
);
1058 if (parameters
->options().gc_sections())
1059 this->gc_mark_dyn_syms(ret
);
1060 ins
.first
->second
= ret
;
1064 was_undefined
= false;
1067 Sized_target
<size
, big_endian
>* target
=
1068 parameters
->sized_target
<size
, big_endian
>();
1069 if (!target
->has_make_symbol())
1070 ret
= new Sized_symbol
<size
>();
1073 ret
= target
->make_symbol(name
, sym
.get_st_type(), object
,
1074 st_shndx
, sym
.get_st_value());
1077 // This means that we don't want a symbol table
1079 if (!is_default_version
)
1080 this->table_
.erase(ins
.first
);
1083 this->table_
.erase(insdefault
.first
);
1084 // Inserting INSDEFAULT invalidated INS.
1085 this->table_
.erase(std::make_pair(name_key
,
1092 ret
->init_object(name
, version
, object
, sym
, st_shndx
, is_ordinary
);
1094 ins
.first
->second
= ret
;
1095 if (is_default_version
)
1097 // This is the first time we have seen NAME/NULL. Point
1098 // it at the new entry for NAME/VERSION.
1099 gold_assert(insdefault
.second
);
1100 insdefault
.first
->second
= ret
;
1104 if (is_default_version
)
1105 ret
->set_is_default();
1108 // Record every time we see a new undefined symbol, to speed up
1110 if (!was_undefined
&& ret
->is_undefined())
1112 ++this->saw_undefined_
;
1113 if (parameters
->options().has_plugins())
1114 parameters
->options().plugins()->new_undefined_symbol(ret
);
1117 // Keep track of common symbols, to speed up common symbol
1118 // allocation. Don't record commons from plugin objects;
1119 // we need to wait until we see the real symbol in the
1120 // replacement file.
1121 if (!was_common
&& ret
->is_common() && ret
->object()->pluginobj() == NULL
)
1123 if (ret
->type() == elfcpp::STT_TLS
)
1124 this->tls_commons_
.push_back(ret
);
1125 else if (!is_ordinary
1126 && st_shndx
== parameters
->target().small_common_shndx())
1127 this->small_commons_
.push_back(ret
);
1128 else if (!is_ordinary
1129 && st_shndx
== parameters
->target().large_common_shndx())
1130 this->large_commons_
.push_back(ret
);
1132 this->commons_
.push_back(ret
);
1135 // If we're not doing a relocatable link, then any symbol with
1136 // hidden or internal visibility is local.
1137 if ((ret
->visibility() == elfcpp::STV_HIDDEN
1138 || ret
->visibility() == elfcpp::STV_INTERNAL
)
1139 && (ret
->binding() == elfcpp::STB_GLOBAL
1140 || ret
->binding() == elfcpp::STB_GNU_UNIQUE
1141 || ret
->binding() == elfcpp::STB_WEAK
)
1142 && !parameters
->options().relocatable())
1143 this->force_local(ret
);
1148 // Add all the symbols in a relocatable object to the hash table.
1150 template<int size
, bool big_endian
>
1152 Symbol_table::add_from_relobj(
1153 Sized_relobj_file
<size
, big_endian
>* relobj
,
1154 const unsigned char* syms
,
1156 size_t symndx_offset
,
1157 const char* sym_names
,
1158 size_t sym_name_size
,
1159 typename Sized_relobj_file
<size
, big_endian
>::Symbols
* sympointers
,
1164 gold_assert(size
== parameters
->target().get_size());
1166 const int sym_size
= elfcpp::Elf_sizes
<size
>::sym_size
;
1168 const bool just_symbols
= relobj
->just_symbols();
1170 const unsigned char* p
= syms
;
1171 for (size_t i
= 0; i
< count
; ++i
, p
+= sym_size
)
1173 (*sympointers
)[i
] = NULL
;
1175 elfcpp::Sym
<size
, big_endian
> sym(p
);
1177 unsigned int st_name
= sym
.get_st_name();
1178 if (st_name
>= sym_name_size
)
1180 relobj
->error(_("bad global symbol name offset %u at %zu"),
1185 const char* name
= sym_names
+ st_name
;
1187 if (!parameters
->options().relocatable()
1190 && strcmp (name
+ (name
[2] == '_'), "__gnu_lto_slim") == 0)
1191 gold_info(_("%s: plugin needed to handle lto object"),
1192 relobj
->name().c_str());
1195 unsigned int st_shndx
= relobj
->adjust_sym_shndx(i
+ symndx_offset
,
1198 unsigned int orig_st_shndx
= st_shndx
;
1200 orig_st_shndx
= elfcpp::SHN_UNDEF
;
1202 if (st_shndx
!= elfcpp::SHN_UNDEF
)
1205 // A symbol defined in a section which we are not including must
1206 // be treated as an undefined symbol.
1207 bool is_defined_in_discarded_section
= false;
1208 if (st_shndx
!= elfcpp::SHN_UNDEF
1210 && !relobj
->is_section_included(st_shndx
)
1211 && !this->is_section_folded(relobj
, st_shndx
))
1213 st_shndx
= elfcpp::SHN_UNDEF
;
1214 is_defined_in_discarded_section
= true;
1217 // In an object file, an '@' in the name separates the symbol
1218 // name from the version name. If there are two '@' characters,
1219 // this is the default version.
1220 const char* ver
= strchr(name
, '@');
1221 Stringpool::Key ver_key
= 0;
1223 // IS_DEFAULT_VERSION: is the version default?
1224 // IS_FORCED_LOCAL: is the symbol forced local?
1225 bool is_default_version
= false;
1226 bool is_forced_local
= false;
1228 // FIXME: For incremental links, we don't store version information,
1229 // so we need to ignore version symbols for now.
1230 if (parameters
->incremental_update() && ver
!= NULL
)
1232 namelen
= ver
- name
;
1238 // The symbol name is of the form foo@VERSION or foo@@VERSION
1239 namelen
= ver
- name
;
1243 is_default_version
= true;
1246 ver
= this->namepool_
.add(ver
, true, &ver_key
);
1248 // We don't want to assign a version to an undefined symbol,
1249 // even if it is listed in the version script. FIXME: What
1250 // about a common symbol?
1253 namelen
= strlen(name
);
1254 if (!this->version_script_
.empty()
1255 && st_shndx
!= elfcpp::SHN_UNDEF
)
1257 // The symbol name did not have a version, but the
1258 // version script may assign a version anyway.
1259 std::string version
;
1261 if (this->version_script_
.get_symbol_version(name
, &version
,
1265 is_forced_local
= true;
1266 else if (!version
.empty())
1268 ver
= this->namepool_
.add_with_length(version
.c_str(),
1272 is_default_version
= true;
1278 elfcpp::Sym
<size
, big_endian
>* psym
= &sym
;
1279 unsigned char symbuf
[sym_size
];
1280 elfcpp::Sym
<size
, big_endian
> sym2(symbuf
);
1283 memcpy(symbuf
, p
, sym_size
);
1284 elfcpp::Sym_write
<size
, big_endian
> sw(symbuf
);
1285 if (orig_st_shndx
!= elfcpp::SHN_UNDEF
1287 && relobj
->e_type() == elfcpp::ET_REL
)
1289 // Symbol values in relocatable object files are section
1290 // relative. This is normally what we want, but since here
1291 // we are converting the symbol to absolute we need to add
1292 // the section address. The section address in an object
1293 // file is normally zero, but people can use a linker
1294 // script to change it.
1295 sw
.put_st_value(sym
.get_st_value()
1296 + relobj
->section_address(orig_st_shndx
));
1298 st_shndx
= elfcpp::SHN_ABS
;
1299 is_ordinary
= false;
1303 // Fix up visibility if object has no-export set.
1304 if (relobj
->no_export()
1305 && (orig_st_shndx
!= elfcpp::SHN_UNDEF
|| !is_ordinary
))
1307 // We may have copied symbol already above.
1310 memcpy(symbuf
, p
, sym_size
);
1314 elfcpp::STV visibility
= sym2
.get_st_visibility();
1315 if (visibility
== elfcpp::STV_DEFAULT
1316 || visibility
== elfcpp::STV_PROTECTED
)
1318 elfcpp::Sym_write
<size
, big_endian
> sw(symbuf
);
1319 unsigned char nonvis
= sym2
.get_st_nonvis();
1320 sw
.put_st_other(elfcpp::STV_HIDDEN
, nonvis
);
1324 Stringpool::Key name_key
;
1325 name
= this->namepool_
.add_with_length(name
, namelen
, true,
1328 Sized_symbol
<size
>* res
;
1329 res
= this->add_from_object(relobj
, name
, name_key
, ver
, ver_key
,
1330 is_default_version
, *psym
, st_shndx
,
1331 is_ordinary
, orig_st_shndx
);
1336 if (is_forced_local
)
1337 this->force_local(res
);
1339 // Do not treat this symbol as garbage if this symbol will be
1340 // exported to the dynamic symbol table. This is true when
1341 // building a shared library or using --export-dynamic and
1342 // the symbol is externally visible.
1343 if (parameters
->options().gc_sections()
1344 && res
->is_externally_visible()
1345 && !res
->is_from_dynobj()
1346 && (parameters
->options().shared()
1347 || parameters
->options().export_dynamic()
1348 || parameters
->options().in_dynamic_list(res
->name())))
1349 this->gc_mark_symbol(res
);
1351 if (is_defined_in_discarded_section
)
1352 res
->set_is_defined_in_discarded_section();
1354 (*sympointers
)[i
] = res
;
1358 // Add a symbol from a plugin-claimed file.
1360 template<int size
, bool big_endian
>
1362 Symbol_table::add_from_pluginobj(
1363 Sized_pluginobj
<size
, big_endian
>* obj
,
1366 elfcpp::Sym
<size
, big_endian
>* sym
)
1368 unsigned int st_shndx
= sym
->get_st_shndx();
1369 bool is_ordinary
= st_shndx
< elfcpp::SHN_LORESERVE
;
1371 Stringpool::Key ver_key
= 0;
1372 bool is_default_version
= false;
1373 bool is_forced_local
= false;
1377 ver
= this->namepool_
.add(ver
, true, &ver_key
);
1379 // We don't want to assign a version to an undefined symbol,
1380 // even if it is listed in the version script. FIXME: What
1381 // about a common symbol?
1384 if (!this->version_script_
.empty()
1385 && st_shndx
!= elfcpp::SHN_UNDEF
)
1387 // The symbol name did not have a version, but the
1388 // version script may assign a version anyway.
1389 std::string version
;
1391 if (this->version_script_
.get_symbol_version(name
, &version
,
1395 is_forced_local
= true;
1396 else if (!version
.empty())
1398 ver
= this->namepool_
.add_with_length(version
.c_str(),
1402 is_default_version
= true;
1408 Stringpool::Key name_key
;
1409 name
= this->namepool_
.add(name
, true, &name_key
);
1411 Sized_symbol
<size
>* res
;
1412 res
= this->add_from_object(obj
, name
, name_key
, ver
, ver_key
,
1413 is_default_version
, *sym
, st_shndx
,
1414 is_ordinary
, st_shndx
);
1419 if (is_forced_local
)
1420 this->force_local(res
);
1425 // Add all the symbols in a dynamic object to the hash table.
1427 template<int size
, bool big_endian
>
1429 Symbol_table::add_from_dynobj(
1430 Sized_dynobj
<size
, big_endian
>* dynobj
,
1431 const unsigned char* syms
,
1433 const char* sym_names
,
1434 size_t sym_name_size
,
1435 const unsigned char* versym
,
1437 const std::vector
<const char*>* version_map
,
1438 typename Sized_relobj_file
<size
, big_endian
>::Symbols
* sympointers
,
1443 gold_assert(size
== parameters
->target().get_size());
1445 if (dynobj
->just_symbols())
1447 gold_error(_("--just-symbols does not make sense with a shared object"));
1451 // FIXME: For incremental links, we don't store version information,
1452 // so we need to ignore version symbols for now.
1453 if (parameters
->incremental_update())
1456 if (versym
!= NULL
&& versym_size
/ 2 < count
)
1458 dynobj
->error(_("too few symbol versions"));
1462 const int sym_size
= elfcpp::Elf_sizes
<size
>::sym_size
;
1464 // We keep a list of all STT_OBJECT symbols, so that we can resolve
1465 // weak aliases. This is necessary because if the dynamic object
1466 // provides the same variable under two names, one of which is a
1467 // weak definition, and the regular object refers to the weak
1468 // definition, we have to put both the weak definition and the
1469 // strong definition into the dynamic symbol table. Given a weak
1470 // definition, the only way that we can find the corresponding
1471 // strong definition, if any, is to search the symbol table.
1472 std::vector
<Sized_symbol
<size
>*> object_symbols
;
1474 const unsigned char* p
= syms
;
1475 const unsigned char* vs
= versym
;
1476 for (size_t i
= 0; i
< count
; ++i
, p
+= sym_size
, vs
+= 2)
1478 elfcpp::Sym
<size
, big_endian
> sym(p
);
1480 if (sympointers
!= NULL
)
1481 (*sympointers
)[i
] = NULL
;
1483 // Ignore symbols with local binding or that have
1484 // internal or hidden visibility.
1485 if (sym
.get_st_bind() == elfcpp::STB_LOCAL
1486 || sym
.get_st_visibility() == elfcpp::STV_INTERNAL
1487 || sym
.get_st_visibility() == elfcpp::STV_HIDDEN
)
1490 // A protected symbol in a shared library must be treated as a
1491 // normal symbol when viewed from outside the shared library.
1492 // Implement this by overriding the visibility here.
1493 // Likewise, an IFUNC symbol in a shared library must be treated
1494 // as a normal FUNC symbol.
1495 elfcpp::Sym
<size
, big_endian
>* psym
= &sym
;
1496 unsigned char symbuf
[sym_size
];
1497 elfcpp::Sym
<size
, big_endian
> sym2(symbuf
);
1498 if (sym
.get_st_visibility() == elfcpp::STV_PROTECTED
1499 || sym
.get_st_type() == elfcpp::STT_GNU_IFUNC
)
1501 memcpy(symbuf
, p
, sym_size
);
1502 elfcpp::Sym_write
<size
, big_endian
> sw(symbuf
);
1503 if (sym
.get_st_visibility() == elfcpp::STV_PROTECTED
)
1504 sw
.put_st_other(elfcpp::STV_DEFAULT
, sym
.get_st_nonvis());
1505 if (sym
.get_st_type() == elfcpp::STT_GNU_IFUNC
)
1506 sw
.put_st_info(sym
.get_st_bind(), elfcpp::STT_FUNC
);
1510 unsigned int st_name
= psym
->get_st_name();
1511 if (st_name
>= sym_name_size
)
1513 dynobj
->error(_("bad symbol name offset %u at %zu"),
1518 const char* name
= sym_names
+ st_name
;
1521 unsigned int st_shndx
= dynobj
->adjust_sym_shndx(i
, psym
->get_st_shndx(),
1524 if (st_shndx
!= elfcpp::SHN_UNDEF
)
1527 Sized_symbol
<size
>* res
;
1531 Stringpool::Key name_key
;
1532 name
= this->namepool_
.add(name
, true, &name_key
);
1533 res
= this->add_from_object(dynobj
, name
, name_key
, NULL
, 0,
1534 false, *psym
, st_shndx
, is_ordinary
,
1539 // Read the version information.
1541 unsigned int v
= elfcpp::Swap
<16, big_endian
>::readval(vs
);
1543 bool hidden
= (v
& elfcpp::VERSYM_HIDDEN
) != 0;
1544 v
&= elfcpp::VERSYM_VERSION
;
1546 // The Sun documentation says that V can be VER_NDX_LOCAL,
1547 // or VER_NDX_GLOBAL, or a version index. The meaning of
1548 // VER_NDX_LOCAL is defined as "Symbol has local scope."
1549 // The old GNU linker will happily generate VER_NDX_LOCAL
1550 // for an undefined symbol. I don't know what the Sun
1551 // linker will generate.
1553 if (v
== static_cast<unsigned int>(elfcpp::VER_NDX_LOCAL
)
1554 && st_shndx
!= elfcpp::SHN_UNDEF
)
1556 // This symbol should not be visible outside the object.
1560 // At this point we are definitely going to add this symbol.
1561 Stringpool::Key name_key
;
1562 name
= this->namepool_
.add(name
, true, &name_key
);
1564 if (v
== static_cast<unsigned int>(elfcpp::VER_NDX_LOCAL
)
1565 || v
== static_cast<unsigned int>(elfcpp::VER_NDX_GLOBAL
))
1567 // This symbol does not have a version.
1568 res
= this->add_from_object(dynobj
, name
, name_key
, NULL
, 0,
1569 false, *psym
, st_shndx
, is_ordinary
,
1574 if (v
>= version_map
->size())
1576 dynobj
->error(_("versym for symbol %zu out of range: %u"),
1581 const char* version
= (*version_map
)[v
];
1582 if (version
== NULL
)
1584 dynobj
->error(_("versym for symbol %zu has no name: %u"),
1589 Stringpool::Key version_key
;
1590 version
= this->namepool_
.add(version
, true, &version_key
);
1592 // If this is an absolute symbol, and the version name
1593 // and symbol name are the same, then this is the
1594 // version definition symbol. These symbols exist to
1595 // support using -u to pull in particular versions. We
1596 // do not want to record a version for them.
1597 if (st_shndx
== elfcpp::SHN_ABS
1599 && name_key
== version_key
)
1600 res
= this->add_from_object(dynobj
, name
, name_key
, NULL
, 0,
1601 false, *psym
, st_shndx
, is_ordinary
,
1605 const bool is_default_version
=
1606 !hidden
&& st_shndx
!= elfcpp::SHN_UNDEF
;
1607 res
= this->add_from_object(dynobj
, name
, name_key
, version
,
1608 version_key
, is_default_version
,
1610 is_ordinary
, st_shndx
);
1618 // Note that it is possible that RES was overridden by an
1619 // earlier object, in which case it can't be aliased here.
1620 if (st_shndx
!= elfcpp::SHN_UNDEF
1622 && psym
->get_st_type() == elfcpp::STT_OBJECT
1623 && res
->source() == Symbol::FROM_OBJECT
1624 && res
->object() == dynobj
)
1625 object_symbols
.push_back(res
);
1627 // If the symbol has protected visibility in the dynobj,
1628 // mark it as such if it was not overridden.
1629 if (res
->source() == Symbol::FROM_OBJECT
1630 && res
->object() == dynobj
1631 && sym
.get_st_visibility() == elfcpp::STV_PROTECTED
)
1632 res
->set_is_protected();
1634 if (sympointers
!= NULL
)
1635 (*sympointers
)[i
] = res
;
1638 this->record_weak_aliases(&object_symbols
);
1641 // Add a symbol from a incremental object file.
1643 template<int size
, bool big_endian
>
1645 Symbol_table::add_from_incrobj(
1649 elfcpp::Sym
<size
, big_endian
>* sym
)
1651 unsigned int st_shndx
= sym
->get_st_shndx();
1652 bool is_ordinary
= st_shndx
< elfcpp::SHN_LORESERVE
;
1654 Stringpool::Key ver_key
= 0;
1655 bool is_default_version
= false;
1657 Stringpool::Key name_key
;
1658 name
= this->namepool_
.add(name
, true, &name_key
);
1660 Sized_symbol
<size
>* res
;
1661 res
= this->add_from_object(obj
, name
, name_key
, ver
, ver_key
,
1662 is_default_version
, *sym
, st_shndx
,
1663 is_ordinary
, st_shndx
);
1668 // This is used to sort weak aliases. We sort them first by section
1669 // index, then by offset, then by weak ahead of strong.
1672 class Weak_alias_sorter
1675 bool operator()(const Sized_symbol
<size
>*, const Sized_symbol
<size
>*) const;
1680 Weak_alias_sorter
<size
>::operator()(const Sized_symbol
<size
>* s1
,
1681 const Sized_symbol
<size
>* s2
) const
1684 unsigned int s1_shndx
= s1
->shndx(&is_ordinary
);
1685 gold_assert(is_ordinary
);
1686 unsigned int s2_shndx
= s2
->shndx(&is_ordinary
);
1687 gold_assert(is_ordinary
);
1688 if (s1_shndx
!= s2_shndx
)
1689 return s1_shndx
< s2_shndx
;
1691 if (s1
->value() != s2
->value())
1692 return s1
->value() < s2
->value();
1693 if (s1
->binding() != s2
->binding())
1695 if (s1
->binding() == elfcpp::STB_WEAK
)
1697 if (s2
->binding() == elfcpp::STB_WEAK
)
1700 return std::string(s1
->name()) < std::string(s2
->name());
1703 // SYMBOLS is a list of object symbols from a dynamic object. Look
1704 // for any weak aliases, and record them so that if we add the weak
1705 // alias to the dynamic symbol table, we also add the corresponding
1710 Symbol_table::record_weak_aliases(std::vector
<Sized_symbol
<size
>*>* symbols
)
1712 // Sort the vector by section index, then by offset, then by weak
1714 std::sort(symbols
->begin(), symbols
->end(), Weak_alias_sorter
<size
>());
1716 // Walk through the vector. For each weak definition, record
1718 for (typename
std::vector
<Sized_symbol
<size
>*>::const_iterator p
=
1720 p
!= symbols
->end();
1723 if ((*p
)->binding() != elfcpp::STB_WEAK
)
1726 // Build a circular list of weak aliases. Each symbol points to
1727 // the next one in the circular list.
1729 Sized_symbol
<size
>* from_sym
= *p
;
1730 typename
std::vector
<Sized_symbol
<size
>*>::const_iterator q
;
1731 for (q
= p
+ 1; q
!= symbols
->end(); ++q
)
1734 if ((*q
)->shndx(&dummy
) != from_sym
->shndx(&dummy
)
1735 || (*q
)->value() != from_sym
->value())
1738 this->weak_aliases_
[from_sym
] = *q
;
1739 from_sym
->set_has_alias();
1745 this->weak_aliases_
[from_sym
] = *p
;
1746 from_sym
->set_has_alias();
1753 // Create and return a specially defined symbol. If ONLY_IF_REF is
1754 // true, then only create the symbol if there is a reference to it.
1755 // If this does not return NULL, it sets *POLDSYM to the existing
1756 // symbol if there is one. This sets *RESOLVE_OLDSYM if we should
1757 // resolve the newly created symbol to the old one. This
1758 // canonicalizes *PNAME and *PVERSION.
1760 template<int size
, bool big_endian
>
1762 Symbol_table::define_special_symbol(const char** pname
, const char** pversion
,
1764 Sized_symbol
<size
>** poldsym
,
1765 bool* resolve_oldsym
, bool is_forced_local
)
1767 *resolve_oldsym
= false;
1770 // If the caller didn't give us a version, see if we get one from
1771 // the version script.
1773 bool is_default_version
= false;
1774 if (!is_forced_local
&& *pversion
== NULL
)
1777 if (this->version_script_
.get_symbol_version(*pname
, &v
, &is_global
))
1779 if (is_global
&& !v
.empty())
1781 *pversion
= v
.c_str();
1782 // If we get the version from a version script, then we
1783 // are also the default version.
1784 is_default_version
= true;
1790 Sized_symbol
<size
>* sym
;
1792 bool add_to_table
= false;
1793 typename
Symbol_table_type::iterator add_loc
= this->table_
.end();
1794 bool add_def_to_table
= false;
1795 typename
Symbol_table_type::iterator add_def_loc
= this->table_
.end();
1799 oldsym
= this->lookup(*pname
, *pversion
);
1800 if (oldsym
== NULL
&& is_default_version
)
1801 oldsym
= this->lookup(*pname
, NULL
);
1802 if (oldsym
== NULL
|| !oldsym
->is_undefined())
1805 *pname
= oldsym
->name();
1806 if (is_default_version
)
1807 *pversion
= this->namepool_
.add(*pversion
, true, NULL
);
1809 *pversion
= oldsym
->version();
1813 // Canonicalize NAME and VERSION.
1814 Stringpool::Key name_key
;
1815 *pname
= this->namepool_
.add(*pname
, true, &name_key
);
1817 Stringpool::Key version_key
= 0;
1818 if (*pversion
!= NULL
)
1819 *pversion
= this->namepool_
.add(*pversion
, true, &version_key
);
1821 Symbol
* const snull
= NULL
;
1822 std::pair
<typename
Symbol_table_type::iterator
, bool> ins
=
1823 this->table_
.insert(std::make_pair(std::make_pair(name_key
,
1827 std::pair
<typename
Symbol_table_type::iterator
, bool> insdefault
=
1828 std::make_pair(this->table_
.end(), false);
1829 if (is_default_version
)
1831 const Stringpool::Key vnull
= 0;
1833 this->table_
.insert(std::make_pair(std::make_pair(name_key
,
1840 // We already have a symbol table entry for NAME/VERSION.
1841 oldsym
= ins
.first
->second
;
1842 gold_assert(oldsym
!= NULL
);
1844 if (is_default_version
)
1846 Sized_symbol
<size
>* soldsym
=
1847 this->get_sized_symbol
<size
>(oldsym
);
1848 this->define_default_version
<size
, big_endian
>(soldsym
,
1855 // We haven't seen this symbol before.
1856 gold_assert(ins
.first
->second
== NULL
);
1858 add_to_table
= true;
1859 add_loc
= ins
.first
;
1861 if (is_default_version
&& !insdefault
.second
)
1863 // We are adding NAME/VERSION, and it is the default
1864 // version. We already have an entry for NAME/NULL.
1865 oldsym
= insdefault
.first
->second
;
1866 *resolve_oldsym
= true;
1872 if (is_default_version
)
1874 add_def_to_table
= true;
1875 add_def_loc
= insdefault
.first
;
1881 const Target
& target
= parameters
->target();
1882 if (!target
.has_make_symbol())
1883 sym
= new Sized_symbol
<size
>();
1886 Sized_target
<size
, big_endian
>* sized_target
=
1887 parameters
->sized_target
<size
, big_endian
>();
1888 sym
= sized_target
->make_symbol(*pname
, elfcpp::STT_NOTYPE
,
1889 NULL
, elfcpp::SHN_UNDEF
, 0);
1895 add_loc
->second
= sym
;
1897 gold_assert(oldsym
!= NULL
);
1899 if (add_def_to_table
)
1900 add_def_loc
->second
= sym
;
1902 *poldsym
= this->get_sized_symbol
<size
>(oldsym
);
1907 // Define a symbol based on an Output_data.
1910 Symbol_table::define_in_output_data(const char* name
,
1911 const char* version
,
1917 elfcpp::STB binding
,
1918 elfcpp::STV visibility
,
1919 unsigned char nonvis
,
1920 bool offset_is_from_end
,
1923 if (parameters
->target().get_size() == 32)
1925 #if defined(HAVE_TARGET_32_LITTLE) || defined(HAVE_TARGET_32_BIG)
1926 return this->do_define_in_output_data
<32>(name
, version
, defined
, od
,
1927 value
, symsize
, type
, binding
,
1935 else if (parameters
->target().get_size() == 64)
1937 #if defined(HAVE_TARGET_64_LITTLE) || defined(HAVE_TARGET_64_BIG)
1938 return this->do_define_in_output_data
<64>(name
, version
, defined
, od
,
1939 value
, symsize
, type
, binding
,
1951 // Define a symbol in an Output_data, sized version.
1955 Symbol_table::do_define_in_output_data(
1957 const char* version
,
1960 typename
elfcpp::Elf_types
<size
>::Elf_Addr value
,
1961 typename
elfcpp::Elf_types
<size
>::Elf_WXword symsize
,
1963 elfcpp::STB binding
,
1964 elfcpp::STV visibility
,
1965 unsigned char nonvis
,
1966 bool offset_is_from_end
,
1969 Sized_symbol
<size
>* sym
;
1970 Sized_symbol
<size
>* oldsym
;
1971 bool resolve_oldsym
;
1972 const bool is_forced_local
= binding
== elfcpp::STB_LOCAL
;
1974 if (parameters
->target().is_big_endian())
1976 #if defined(HAVE_TARGET_32_BIG) || defined(HAVE_TARGET_64_BIG)
1977 sym
= this->define_special_symbol
<size
, true>(&name
, &version
,
1978 only_if_ref
, &oldsym
,
1987 #if defined(HAVE_TARGET_32_LITTLE) || defined(HAVE_TARGET_64_LITTLE)
1988 sym
= this->define_special_symbol
<size
, false>(&name
, &version
,
1989 only_if_ref
, &oldsym
,
2000 sym
->init_output_data(name
, version
, od
, value
, symsize
, type
, binding
,
2001 visibility
, nonvis
, offset_is_from_end
,
2002 defined
== PREDEFINED
);
2006 if (is_forced_local
|| this->version_script_
.symbol_is_local(name
))
2007 this->force_local(sym
);
2008 else if (version
!= NULL
)
2009 sym
->set_is_default();
2013 if (Symbol_table::should_override_with_special(oldsym
, type
, defined
))
2014 this->override_with_special(oldsym
, sym
);
2020 if (defined
== PREDEFINED
2021 && (is_forced_local
|| this->version_script_
.symbol_is_local(name
)))
2022 this->force_local(oldsym
);
2028 // Define a symbol based on an Output_segment.
2031 Symbol_table::define_in_output_segment(const char* name
,
2032 const char* version
,
2038 elfcpp::STB binding
,
2039 elfcpp::STV visibility
,
2040 unsigned char nonvis
,
2041 Symbol::Segment_offset_base offset_base
,
2044 if (parameters
->target().get_size() == 32)
2046 #if defined(HAVE_TARGET_32_LITTLE) || defined(HAVE_TARGET_32_BIG)
2047 return this->do_define_in_output_segment
<32>(name
, version
, defined
, os
,
2048 value
, symsize
, type
,
2049 binding
, visibility
, nonvis
,
2050 offset_base
, only_if_ref
);
2055 else if (parameters
->target().get_size() == 64)
2057 #if defined(HAVE_TARGET_64_LITTLE) || defined(HAVE_TARGET_64_BIG)
2058 return this->do_define_in_output_segment
<64>(name
, version
, defined
, os
,
2059 value
, symsize
, type
,
2060 binding
, visibility
, nonvis
,
2061 offset_base
, only_if_ref
);
2070 // Define a symbol in an Output_segment, sized version.
2074 Symbol_table::do_define_in_output_segment(
2076 const char* version
,
2079 typename
elfcpp::Elf_types
<size
>::Elf_Addr value
,
2080 typename
elfcpp::Elf_types
<size
>::Elf_WXword symsize
,
2082 elfcpp::STB binding
,
2083 elfcpp::STV visibility
,
2084 unsigned char nonvis
,
2085 Symbol::Segment_offset_base offset_base
,
2088 Sized_symbol
<size
>* sym
;
2089 Sized_symbol
<size
>* oldsym
;
2090 bool resolve_oldsym
;
2091 const bool is_forced_local
= binding
== elfcpp::STB_LOCAL
;
2093 if (parameters
->target().is_big_endian())
2095 #if defined(HAVE_TARGET_32_BIG) || defined(HAVE_TARGET_64_BIG)
2096 sym
= this->define_special_symbol
<size
, true>(&name
, &version
,
2097 only_if_ref
, &oldsym
,
2106 #if defined(HAVE_TARGET_32_LITTLE) || defined(HAVE_TARGET_64_LITTLE)
2107 sym
= this->define_special_symbol
<size
, false>(&name
, &version
,
2108 only_if_ref
, &oldsym
,
2119 sym
->init_output_segment(name
, version
, os
, value
, symsize
, type
, binding
,
2120 visibility
, nonvis
, offset_base
,
2121 defined
== PREDEFINED
);
2125 if (is_forced_local
|| this->version_script_
.symbol_is_local(name
))
2126 this->force_local(sym
);
2127 else if (version
!= NULL
)
2128 sym
->set_is_default();
2132 if (Symbol_table::should_override_with_special(oldsym
, type
, defined
))
2133 this->override_with_special(oldsym
, sym
);
2139 if (is_forced_local
|| this->version_script_
.symbol_is_local(name
))
2140 this->force_local(oldsym
);
2146 // Define a special symbol with a constant value. It is a multiple
2147 // definition error if this symbol is already defined.
2150 Symbol_table::define_as_constant(const char* name
,
2151 const char* version
,
2156 elfcpp::STB binding
,
2157 elfcpp::STV visibility
,
2158 unsigned char nonvis
,
2160 bool force_override
)
2162 if (parameters
->target().get_size() == 32)
2164 #if defined(HAVE_TARGET_32_LITTLE) || defined(HAVE_TARGET_32_BIG)
2165 return this->do_define_as_constant
<32>(name
, version
, defined
, value
,
2166 symsize
, type
, binding
,
2167 visibility
, nonvis
, only_if_ref
,
2173 else if (parameters
->target().get_size() == 64)
2175 #if defined(HAVE_TARGET_64_LITTLE) || defined(HAVE_TARGET_64_BIG)
2176 return this->do_define_as_constant
<64>(name
, version
, defined
, value
,
2177 symsize
, type
, binding
,
2178 visibility
, nonvis
, only_if_ref
,
2188 // Define a symbol as a constant, sized version.
2192 Symbol_table::do_define_as_constant(
2194 const char* version
,
2196 typename
elfcpp::Elf_types
<size
>::Elf_Addr value
,
2197 typename
elfcpp::Elf_types
<size
>::Elf_WXword symsize
,
2199 elfcpp::STB binding
,
2200 elfcpp::STV visibility
,
2201 unsigned char nonvis
,
2203 bool force_override
)
2205 Sized_symbol
<size
>* sym
;
2206 Sized_symbol
<size
>* oldsym
;
2207 bool resolve_oldsym
;
2208 const bool is_forced_local
= binding
== elfcpp::STB_LOCAL
;
2210 if (parameters
->target().is_big_endian())
2212 #if defined(HAVE_TARGET_32_BIG) || defined(HAVE_TARGET_64_BIG)
2213 sym
= this->define_special_symbol
<size
, true>(&name
, &version
,
2214 only_if_ref
, &oldsym
,
2223 #if defined(HAVE_TARGET_32_LITTLE) || defined(HAVE_TARGET_64_LITTLE)
2224 sym
= this->define_special_symbol
<size
, false>(&name
, &version
,
2225 only_if_ref
, &oldsym
,
2236 sym
->init_constant(name
, version
, value
, symsize
, type
, binding
, visibility
,
2237 nonvis
, defined
== PREDEFINED
);
2241 // Version symbols are absolute symbols with name == version.
2242 // We don't want to force them to be local.
2243 if ((version
== NULL
2246 && (is_forced_local
|| this->version_script_
.symbol_is_local(name
)))
2247 this->force_local(sym
);
2248 else if (version
!= NULL
2249 && (name
!= version
|| value
!= 0))
2250 sym
->set_is_default();
2255 || Symbol_table::should_override_with_special(oldsym
, type
, defined
))
2256 this->override_with_special(oldsym
, sym
);
2262 if (is_forced_local
|| this->version_script_
.symbol_is_local(name
))
2263 this->force_local(oldsym
);
2269 // Define a set of symbols in output sections.
2272 Symbol_table::define_symbols(const Layout
* layout
, int count
,
2273 const Define_symbol_in_section
* p
,
2276 for (int i
= 0; i
< count
; ++i
, ++p
)
2278 Output_section
* os
= layout
->find_output_section(p
->output_section
);
2280 this->define_in_output_data(p
->name
, NULL
, PREDEFINED
, os
, p
->value
,
2281 p
->size
, p
->type
, p
->binding
,
2282 p
->visibility
, p
->nonvis
,
2283 p
->offset_is_from_end
,
2284 only_if_ref
|| p
->only_if_ref
);
2286 this->define_as_constant(p
->name
, NULL
, PREDEFINED
, 0, p
->size
,
2287 p
->type
, p
->binding
, p
->visibility
, p
->nonvis
,
2288 only_if_ref
|| p
->only_if_ref
,
2293 // Define a set of symbols in output segments.
2296 Symbol_table::define_symbols(const Layout
* layout
, int count
,
2297 const Define_symbol_in_segment
* p
,
2300 for (int i
= 0; i
< count
; ++i
, ++p
)
2302 Output_segment
* os
= layout
->find_output_segment(p
->segment_type
,
2303 p
->segment_flags_set
,
2304 p
->segment_flags_clear
);
2306 this->define_in_output_segment(p
->name
, NULL
, PREDEFINED
, os
, p
->value
,
2307 p
->size
, p
->type
, p
->binding
,
2308 p
->visibility
, p
->nonvis
,
2310 only_if_ref
|| p
->only_if_ref
);
2312 this->define_as_constant(p
->name
, NULL
, PREDEFINED
, 0, p
->size
,
2313 p
->type
, p
->binding
, p
->visibility
, p
->nonvis
,
2314 only_if_ref
|| p
->only_if_ref
,
2319 // Define CSYM using a COPY reloc. POSD is the Output_data where the
2320 // symbol should be defined--typically a .dyn.bss section. VALUE is
2321 // the offset within POSD.
2325 Symbol_table::define_with_copy_reloc(
2326 Sized_symbol
<size
>* csym
,
2328 typename
elfcpp::Elf_types
<size
>::Elf_Addr value
)
2330 gold_assert(csym
->is_from_dynobj());
2331 gold_assert(!csym
->is_copied_from_dynobj());
2332 Object
* object
= csym
->object();
2333 gold_assert(object
->is_dynamic());
2334 Dynobj
* dynobj
= static_cast<Dynobj
*>(object
);
2336 // Our copied variable has to override any variable in a shared
2338 elfcpp::STB binding
= csym
->binding();
2339 if (binding
== elfcpp::STB_WEAK
)
2340 binding
= elfcpp::STB_GLOBAL
;
2342 this->define_in_output_data(csym
->name(), csym
->version(), COPY
,
2343 posd
, value
, csym
->symsize(),
2344 csym
->type(), binding
,
2345 csym
->visibility(), csym
->nonvis(),
2348 csym
->set_is_copied_from_dynobj();
2349 csym
->set_needs_dynsym_entry();
2351 this->copied_symbol_dynobjs_
[csym
] = dynobj
;
2353 // We have now defined all aliases, but we have not entered them all
2354 // in the copied_symbol_dynobjs_ map.
2355 if (csym
->has_alias())
2360 sym
= this->weak_aliases_
[sym
];
2363 gold_assert(sym
->output_data() == posd
);
2365 sym
->set_is_copied_from_dynobj();
2366 this->copied_symbol_dynobjs_
[sym
] = dynobj
;
2371 // SYM is defined using a COPY reloc. Return the dynamic object where
2372 // the original definition was found.
2375 Symbol_table::get_copy_source(const Symbol
* sym
) const
2377 gold_assert(sym
->is_copied_from_dynobj());
2378 Copied_symbol_dynobjs::const_iterator p
=
2379 this->copied_symbol_dynobjs_
.find(sym
);
2380 gold_assert(p
!= this->copied_symbol_dynobjs_
.end());
2384 // Add any undefined symbols named on the command line.
2387 Symbol_table::add_undefined_symbols_from_command_line(Layout
* layout
)
2389 if (parameters
->options().any_undefined()
2390 || layout
->script_options()->any_unreferenced())
2392 if (parameters
->target().get_size() == 32)
2394 #if defined(HAVE_TARGET_32_LITTLE) || defined(HAVE_TARGET_32_BIG)
2395 this->do_add_undefined_symbols_from_command_line
<32>(layout
);
2400 else if (parameters
->target().get_size() == 64)
2402 #if defined(HAVE_TARGET_64_LITTLE) || defined(HAVE_TARGET_64_BIG)
2403 this->do_add_undefined_symbols_from_command_line
<64>(layout
);
2415 Symbol_table::do_add_undefined_symbols_from_command_line(Layout
* layout
)
2417 for (options::String_set::const_iterator p
=
2418 parameters
->options().undefined_begin();
2419 p
!= parameters
->options().undefined_end();
2421 this->add_undefined_symbol_from_command_line
<size
>(p
->c_str());
2423 for (options::String_set::const_iterator p
=
2424 parameters
->options().export_dynamic_symbol_begin();
2425 p
!= parameters
->options().export_dynamic_symbol_end();
2427 this->add_undefined_symbol_from_command_line
<size
>(p
->c_str());
2429 for (Script_options::referenced_const_iterator p
=
2430 layout
->script_options()->referenced_begin();
2431 p
!= layout
->script_options()->referenced_end();
2433 this->add_undefined_symbol_from_command_line
<size
>(p
->c_str());
2438 Symbol_table::add_undefined_symbol_from_command_line(const char* name
)
2440 if (this->lookup(name
) != NULL
)
2443 const char* version
= NULL
;
2445 Sized_symbol
<size
>* sym
;
2446 Sized_symbol
<size
>* oldsym
;
2447 bool resolve_oldsym
;
2448 if (parameters
->target().is_big_endian())
2450 #if defined(HAVE_TARGET_32_BIG) || defined(HAVE_TARGET_64_BIG)
2451 sym
= this->define_special_symbol
<size
, true>(&name
, &version
,
2461 #if defined(HAVE_TARGET_32_LITTLE) || defined(HAVE_TARGET_64_LITTLE)
2462 sym
= this->define_special_symbol
<size
, false>(&name
, &version
,
2471 gold_assert(oldsym
== NULL
);
2473 sym
->init_undefined(name
, version
, 0, elfcpp::STT_NOTYPE
, elfcpp::STB_GLOBAL
,
2474 elfcpp::STV_DEFAULT
, 0);
2475 ++this->saw_undefined_
;
2478 // Set the dynamic symbol indexes. INDEX is the index of the first
2479 // global dynamic symbol. Pointers to the global symbols are stored
2480 // into the vector SYMS. The names are added to DYNPOOL.
2481 // This returns an updated dynamic symbol index.
2484 Symbol_table::set_dynsym_indexes(unsigned int index
,
2485 unsigned int* pforced_local_count
,
2486 std::vector
<Symbol
*>* syms
,
2487 Stringpool
* dynpool
,
2490 std::vector
<Symbol
*> as_needed_sym
;
2492 // First process all the symbols which have been forced to be local,
2493 // as they must appear before all global symbols.
2494 unsigned int forced_local_count
= 0;
2495 for (Forced_locals::iterator p
= this->forced_locals_
.begin();
2496 p
!= this->forced_locals_
.end();
2500 gold_assert(sym
->is_forced_local());
2501 if (sym
->has_dynsym_index())
2503 if (!sym
->should_add_dynsym_entry(this))
2504 sym
->set_dynsym_index(-1U);
2507 sym
->set_dynsym_index(index
);
2509 ++forced_local_count
;
2510 dynpool
->add(sym
->name(), false, NULL
);
2513 *pforced_local_count
= forced_local_count
;
2515 // Allow a target to set dynsym indexes.
2516 if (parameters
->target().has_custom_set_dynsym_indexes())
2518 std::vector
<Symbol
*> dyn_symbols
;
2519 for (Symbol_table_type::iterator p
= this->table_
.begin();
2520 p
!= this->table_
.end();
2523 Symbol
* sym
= p
->second
;
2524 if (sym
->is_forced_local())
2526 if (!sym
->should_add_dynsym_entry(this))
2527 sym
->set_dynsym_index(-1U);
2529 dyn_symbols
.push_back(sym
);
2532 return parameters
->target().set_dynsym_indexes(&dyn_symbols
, index
, syms
,
2533 dynpool
, versions
, this);
2536 for (Symbol_table_type::iterator p
= this->table_
.begin();
2537 p
!= this->table_
.end();
2540 Symbol
* sym
= p
->second
;
2542 if (sym
->is_forced_local())
2545 // Note that SYM may already have a dynamic symbol index, since
2546 // some symbols appear more than once in the symbol table, with
2547 // and without a version.
2549 if (!sym
->should_add_dynsym_entry(this))
2550 sym
->set_dynsym_index(-1U);
2551 else if (!sym
->has_dynsym_index())
2553 sym
->set_dynsym_index(index
);
2555 syms
->push_back(sym
);
2556 dynpool
->add(sym
->name(), false, NULL
);
2558 // If the symbol is defined in a dynamic object and is
2559 // referenced strongly in a regular object, then mark the
2560 // dynamic object as needed. This is used to implement
2562 if (sym
->is_from_dynobj()
2564 && !sym
->is_undef_binding_weak())
2565 sym
->object()->set_is_needed();
2567 // Record any version information, except those from
2568 // as-needed libraries not seen to be needed. Note that the
2569 // is_needed state for such libraries can change in this loop.
2570 if (sym
->version() != NULL
)
2572 if (!sym
->is_from_dynobj()
2573 || !sym
->object()->as_needed()
2574 || sym
->object()->is_needed())
2575 versions
->record_version(this, dynpool
, sym
);
2577 as_needed_sym
.push_back(sym
);
2582 // Process version information for symbols from as-needed libraries.
2583 for (std::vector
<Symbol
*>::iterator p
= as_needed_sym
.begin();
2584 p
!= as_needed_sym
.end();
2589 if (sym
->object()->is_needed())
2590 versions
->record_version(this, dynpool
, sym
);
2592 sym
->clear_version();
2595 // Finish up the versions. In some cases this may add new dynamic
2597 index
= versions
->finalize(this, index
, syms
);
2599 // Process target-specific symbols.
2600 for (std::vector
<Symbol
*>::iterator p
= this->target_symbols_
.begin();
2601 p
!= this->target_symbols_
.end();
2604 (*p
)->set_dynsym_index(index
);
2606 syms
->push_back(*p
);
2607 dynpool
->add((*p
)->name(), false, NULL
);
2613 // Set the final values for all the symbols. The index of the first
2614 // global symbol in the output file is *PLOCAL_SYMCOUNT. Record the
2615 // file offset OFF. Add their names to POOL. Return the new file
2616 // offset. Update *PLOCAL_SYMCOUNT if necessary. DYNOFF and
2617 // DYN_GLOBAL_INDEX refer to the start of the symbols that will be
2618 // written from the global symbol table in Symtab::write_globals(),
2619 // which will include forced-local symbols. DYN_GLOBAL_INDEX is
2620 // not necessarily the same as the sh_info field for the .dynsym
2621 // section, which will point to the first real global symbol.
2624 Symbol_table::finalize(off_t off
, off_t dynoff
, size_t dyn_global_index
,
2625 size_t dyncount
, Stringpool
* pool
,
2626 unsigned int* plocal_symcount
)
2630 gold_assert(*plocal_symcount
!= 0);
2631 this->first_global_index_
= *plocal_symcount
;
2633 this->dynamic_offset_
= dynoff
;
2634 this->first_dynamic_global_index_
= dyn_global_index
;
2635 this->dynamic_count_
= dyncount
;
2637 if (parameters
->target().get_size() == 32)
2639 #if defined(HAVE_TARGET_32_BIG) || defined(HAVE_TARGET_32_LITTLE)
2640 ret
= this->sized_finalize
<32>(off
, pool
, plocal_symcount
);
2645 else if (parameters
->target().get_size() == 64)
2647 #if defined(HAVE_TARGET_64_BIG) || defined(HAVE_TARGET_64_LITTLE)
2648 ret
= this->sized_finalize
<64>(off
, pool
, plocal_symcount
);
2656 // Now that we have the final symbol table, we can reliably note
2657 // which symbols should get warnings.
2658 this->warnings_
.note_warnings(this);
2663 // SYM is going into the symbol table at *PINDEX. Add the name to
2664 // POOL, update *PINDEX and *POFF.
2668 Symbol_table::add_to_final_symtab(Symbol
* sym
, Stringpool
* pool
,
2669 unsigned int* pindex
, off_t
* poff
)
2671 sym
->set_symtab_index(*pindex
);
2672 if (sym
->version() == NULL
|| !parameters
->options().relocatable())
2673 pool
->add(sym
->name(), false, NULL
);
2675 pool
->add(sym
->versioned_name(), true, NULL
);
2677 *poff
+= elfcpp::Elf_sizes
<size
>::sym_size
;
2680 // Set the final value for all the symbols. This is called after
2681 // Layout::finalize, so all the output sections have their final
2686 Symbol_table::sized_finalize(off_t off
, Stringpool
* pool
,
2687 unsigned int* plocal_symcount
)
2689 off
= align_address(off
, size
>> 3);
2690 this->offset_
= off
;
2692 unsigned int index
= *plocal_symcount
;
2693 const unsigned int orig_index
= index
;
2695 // First do all the symbols which have been forced to be local, as
2696 // they must appear before all global symbols.
2697 for (Forced_locals::iterator p
= this->forced_locals_
.begin();
2698 p
!= this->forced_locals_
.end();
2702 gold_assert(sym
->is_forced_local());
2703 if (this->sized_finalize_symbol
<size
>(sym
))
2705 this->add_to_final_symtab
<size
>(sym
, pool
, &index
, &off
);
2710 // Now do all the remaining symbols.
2711 for (Symbol_table_type::iterator p
= this->table_
.begin();
2712 p
!= this->table_
.end();
2715 Symbol
* sym
= p
->second
;
2716 if (this->sized_finalize_symbol
<size
>(sym
))
2717 this->add_to_final_symtab
<size
>(sym
, pool
, &index
, &off
);
2720 // Now do target-specific symbols.
2721 for (std::vector
<Symbol
*>::iterator p
= this->target_symbols_
.begin();
2722 p
!= this->target_symbols_
.end();
2725 this->add_to_final_symtab
<size
>(*p
, pool
, &index
, &off
);
2728 this->output_count_
= index
- orig_index
;
2733 // Compute the final value of SYM and store status in location PSTATUS.
2734 // During relaxation, this may be called multiple times for a symbol to
2735 // compute its would-be final value in each relaxation pass.
2738 typename Sized_symbol
<size
>::Value_type
2739 Symbol_table::compute_final_value(
2740 const Sized_symbol
<size
>* sym
,
2741 Compute_final_value_status
* pstatus
) const
2743 typedef typename Sized_symbol
<size
>::Value_type Value_type
;
2746 switch (sym
->source())
2748 case Symbol::FROM_OBJECT
:
2751 unsigned int shndx
= sym
->shndx(&is_ordinary
);
2754 && shndx
!= elfcpp::SHN_ABS
2755 && !Symbol::is_common_shndx(shndx
))
2757 *pstatus
= CFVS_UNSUPPORTED_SYMBOL_SECTION
;
2761 Object
* symobj
= sym
->object();
2762 if (symobj
->is_dynamic())
2765 shndx
= elfcpp::SHN_UNDEF
;
2767 else if (symobj
->pluginobj() != NULL
)
2770 shndx
= elfcpp::SHN_UNDEF
;
2772 else if (shndx
== elfcpp::SHN_UNDEF
)
2774 else if (!is_ordinary
2775 && (shndx
== elfcpp::SHN_ABS
2776 || Symbol::is_common_shndx(shndx
)))
2777 value
= sym
->value();
2780 Relobj
* relobj
= static_cast<Relobj
*>(symobj
);
2781 Output_section
* os
= relobj
->output_section(shndx
);
2783 if (this->is_section_folded(relobj
, shndx
))
2785 gold_assert(os
== NULL
);
2786 // Get the os of the section it is folded onto.
2787 Section_id folded
= this->icf_
->get_folded_section(relobj
,
2789 gold_assert(folded
.first
!= NULL
);
2790 Relobj
* folded_obj
= reinterpret_cast<Relobj
*>(folded
.first
);
2791 unsigned folded_shndx
= folded
.second
;
2793 os
= folded_obj
->output_section(folded_shndx
);
2794 gold_assert(os
!= NULL
);
2796 // Replace (relobj, shndx) with canonical ICF input section.
2797 shndx
= folded_shndx
;
2798 relobj
= folded_obj
;
2801 uint64_t secoff64
= relobj
->output_section_offset(shndx
);
2804 bool static_or_reloc
= (parameters
->doing_static_link() ||
2805 parameters
->options().relocatable());
2806 gold_assert(static_or_reloc
|| sym
->dynsym_index() == -1U);
2808 *pstatus
= CFVS_NO_OUTPUT_SECTION
;
2812 if (secoff64
== -1ULL)
2814 // The section needs special handling (e.g., a merge section).
2816 value
= os
->output_address(relobj
, shndx
, sym
->value());
2821 convert_types
<Value_type
, uint64_t>(secoff64
);
2822 if (sym
->type() == elfcpp::STT_TLS
)
2823 value
= sym
->value() + os
->tls_offset() + secoff
;
2825 value
= sym
->value() + os
->address() + secoff
;
2831 case Symbol::IN_OUTPUT_DATA
:
2833 Output_data
* od
= sym
->output_data();
2834 value
= sym
->value();
2835 if (sym
->type() != elfcpp::STT_TLS
)
2836 value
+= od
->address();
2839 Output_section
* os
= od
->output_section();
2840 gold_assert(os
!= NULL
);
2841 value
+= os
->tls_offset() + (od
->address() - os
->address());
2843 if (sym
->offset_is_from_end())
2844 value
+= od
->data_size();
2848 case Symbol::IN_OUTPUT_SEGMENT
:
2850 Output_segment
* os
= sym
->output_segment();
2851 value
= sym
->value();
2852 if (sym
->type() != elfcpp::STT_TLS
)
2853 value
+= os
->vaddr();
2854 switch (sym
->offset_base())
2856 case Symbol::SEGMENT_START
:
2858 case Symbol::SEGMENT_END
:
2859 value
+= os
->memsz();
2861 case Symbol::SEGMENT_BSS
:
2862 value
+= os
->filesz();
2870 case Symbol::IS_CONSTANT
:
2871 value
= sym
->value();
2874 case Symbol::IS_UNDEFINED
:
2886 // Finalize the symbol SYM. This returns true if the symbol should be
2887 // added to the symbol table, false otherwise.
2891 Symbol_table::sized_finalize_symbol(Symbol
* unsized_sym
)
2893 typedef typename Sized_symbol
<size
>::Value_type Value_type
;
2895 Sized_symbol
<size
>* sym
= static_cast<Sized_symbol
<size
>*>(unsized_sym
);
2897 // The default version of a symbol may appear twice in the symbol
2898 // table. We only need to finalize it once.
2899 if (sym
->has_symtab_index())
2904 gold_assert(!sym
->has_symtab_index());
2905 sym
->set_symtab_index(-1U);
2906 gold_assert(sym
->dynsym_index() == -1U);
2910 // If the symbol is only present on plugin files, the plugin decided we
2912 if (!sym
->in_real_elf())
2914 gold_assert(!sym
->has_symtab_index());
2915 sym
->set_symtab_index(-1U);
2919 // Compute final symbol value.
2920 Compute_final_value_status status
;
2921 Value_type value
= this->compute_final_value(sym
, &status
);
2927 case CFVS_UNSUPPORTED_SYMBOL_SECTION
:
2930 unsigned int shndx
= sym
->shndx(&is_ordinary
);
2931 gold_error(_("%s: unsupported symbol section 0x%x"),
2932 sym
->demangled_name().c_str(), shndx
);
2935 case CFVS_NO_OUTPUT_SECTION
:
2936 sym
->set_symtab_index(-1U);
2942 sym
->set_value(value
);
2944 if (parameters
->options().strip_all()
2945 || !parameters
->options().should_retain_symbol(sym
->name()))
2947 sym
->set_symtab_index(-1U);
2954 // Write out the global symbols.
2957 Symbol_table::write_globals(const Stringpool
* sympool
,
2958 const Stringpool
* dynpool
,
2959 Output_symtab_xindex
* symtab_xindex
,
2960 Output_symtab_xindex
* dynsym_xindex
,
2961 Output_file
* of
) const
2963 switch (parameters
->size_and_endianness())
2965 #ifdef HAVE_TARGET_32_LITTLE
2966 case Parameters::TARGET_32_LITTLE
:
2967 this->sized_write_globals
<32, false>(sympool
, dynpool
, symtab_xindex
,
2971 #ifdef HAVE_TARGET_32_BIG
2972 case Parameters::TARGET_32_BIG
:
2973 this->sized_write_globals
<32, true>(sympool
, dynpool
, symtab_xindex
,
2977 #ifdef HAVE_TARGET_64_LITTLE
2978 case Parameters::TARGET_64_LITTLE
:
2979 this->sized_write_globals
<64, false>(sympool
, dynpool
, symtab_xindex
,
2983 #ifdef HAVE_TARGET_64_BIG
2984 case Parameters::TARGET_64_BIG
:
2985 this->sized_write_globals
<64, true>(sympool
, dynpool
, symtab_xindex
,
2994 // Write out the global symbols.
2996 template<int size
, bool big_endian
>
2998 Symbol_table::sized_write_globals(const Stringpool
* sympool
,
2999 const Stringpool
* dynpool
,
3000 Output_symtab_xindex
* symtab_xindex
,
3001 Output_symtab_xindex
* dynsym_xindex
,
3002 Output_file
* of
) const
3004 const Target
& target
= parameters
->target();
3006 const int sym_size
= elfcpp::Elf_sizes
<size
>::sym_size
;
3008 const unsigned int output_count
= this->output_count_
;
3009 const section_size_type oview_size
= output_count
* sym_size
;
3010 const unsigned int first_global_index
= this->first_global_index_
;
3011 unsigned char* psyms
;
3012 if (this->offset_
== 0 || output_count
== 0)
3015 psyms
= of
->get_output_view(this->offset_
, oview_size
);
3017 const unsigned int dynamic_count
= this->dynamic_count_
;
3018 const section_size_type dynamic_size
= dynamic_count
* sym_size
;
3019 const unsigned int first_dynamic_global_index
=
3020 this->first_dynamic_global_index_
;
3021 unsigned char* dynamic_view
;
3022 if (this->dynamic_offset_
== 0 || dynamic_count
== 0)
3023 dynamic_view
= NULL
;
3025 dynamic_view
= of
->get_output_view(this->dynamic_offset_
, dynamic_size
);
3027 for (Symbol_table_type::const_iterator p
= this->table_
.begin();
3028 p
!= this->table_
.end();
3031 Sized_symbol
<size
>* sym
= static_cast<Sized_symbol
<size
>*>(p
->second
);
3033 // Possibly warn about unresolved symbols in shared libraries.
3034 this->warn_about_undefined_dynobj_symbol(sym
);
3036 unsigned int sym_index
= sym
->symtab_index();
3037 unsigned int dynsym_index
;
3038 if (dynamic_view
== NULL
)
3041 dynsym_index
= sym
->dynsym_index();
3043 if (sym_index
== -1U && dynsym_index
== -1U)
3045 // This symbol is not included in the output file.
3050 typename
elfcpp::Elf_types
<size
>::Elf_Addr sym_value
= sym
->value();
3051 typename
elfcpp::Elf_types
<size
>::Elf_Addr dynsym_value
= sym_value
;
3052 elfcpp::STB binding
= sym
->binding();
3054 // If --weak-unresolved-symbols is set, change binding of unresolved
3055 // global symbols to STB_WEAK.
3056 if (parameters
->options().weak_unresolved_symbols()
3057 && binding
== elfcpp::STB_GLOBAL
3058 && sym
->is_undefined())
3059 binding
= elfcpp::STB_WEAK
;
3061 // If --no-gnu-unique is set, change STB_GNU_UNIQUE to STB_GLOBAL.
3062 if (binding
== elfcpp::STB_GNU_UNIQUE
3063 && !parameters
->options().gnu_unique())
3064 binding
= elfcpp::STB_GLOBAL
;
3066 switch (sym
->source())
3068 case Symbol::FROM_OBJECT
:
3071 unsigned int in_shndx
= sym
->shndx(&is_ordinary
);
3074 && in_shndx
!= elfcpp::SHN_ABS
3075 && !Symbol::is_common_shndx(in_shndx
))
3077 gold_error(_("%s: unsupported symbol section 0x%x"),
3078 sym
->demangled_name().c_str(), in_shndx
);
3083 Object
* symobj
= sym
->object();
3084 if (symobj
->is_dynamic())
3086 if (sym
->needs_dynsym_value())
3087 dynsym_value
= target
.dynsym_value(sym
);
3088 shndx
= elfcpp::SHN_UNDEF
;
3089 if (sym
->is_undef_binding_weak())
3090 binding
= elfcpp::STB_WEAK
;
3092 binding
= elfcpp::STB_GLOBAL
;
3094 else if (symobj
->pluginobj() != NULL
)
3095 shndx
= elfcpp::SHN_UNDEF
;
3096 else if (in_shndx
== elfcpp::SHN_UNDEF
3098 && (in_shndx
== elfcpp::SHN_ABS
3099 || Symbol::is_common_shndx(in_shndx
))))
3103 Relobj
* relobj
= static_cast<Relobj
*>(symobj
);
3104 Output_section
* os
= relobj
->output_section(in_shndx
);
3105 if (this->is_section_folded(relobj
, in_shndx
))
3107 // This global symbol must be written out even though
3109 // Get the os of the section it is folded onto.
3111 this->icf_
->get_folded_section(relobj
, in_shndx
);
3112 gold_assert(folded
.first
!=NULL
);
3113 Relobj
* folded_obj
=
3114 reinterpret_cast<Relobj
*>(folded
.first
);
3115 os
= folded_obj
->output_section(folded
.second
);
3116 gold_assert(os
!= NULL
);
3118 gold_assert(os
!= NULL
);
3119 shndx
= os
->out_shndx();
3121 if (shndx
>= elfcpp::SHN_LORESERVE
)
3123 if (sym_index
!= -1U)
3124 symtab_xindex
->add(sym_index
, shndx
);
3125 if (dynsym_index
!= -1U)
3126 dynsym_xindex
->add(dynsym_index
, shndx
);
3127 shndx
= elfcpp::SHN_XINDEX
;
3130 // In object files symbol values are section
3132 if (parameters
->options().relocatable())
3133 sym_value
-= os
->address();
3139 case Symbol::IN_OUTPUT_DATA
:
3141 Output_data
* od
= sym
->output_data();
3143 shndx
= od
->out_shndx();
3144 if (shndx
>= elfcpp::SHN_LORESERVE
)
3146 if (sym_index
!= -1U)
3147 symtab_xindex
->add(sym_index
, shndx
);
3148 if (dynsym_index
!= -1U)
3149 dynsym_xindex
->add(dynsym_index
, shndx
);
3150 shndx
= elfcpp::SHN_XINDEX
;
3153 // In object files symbol values are section
3155 if (parameters
->options().relocatable())
3157 Output_section
* os
= od
->output_section();
3158 gold_assert(os
!= NULL
);
3159 sym_value
-= os
->address();
3164 case Symbol::IN_OUTPUT_SEGMENT
:
3166 Output_segment
* oseg
= sym
->output_segment();
3167 Output_section
* osect
= oseg
->first_section();
3169 shndx
= elfcpp::SHN_ABS
;
3171 shndx
= osect
->out_shndx();
3175 case Symbol::IS_CONSTANT
:
3176 shndx
= elfcpp::SHN_ABS
;
3179 case Symbol::IS_UNDEFINED
:
3180 shndx
= elfcpp::SHN_UNDEF
;
3187 if (sym_index
!= -1U)
3189 sym_index
-= first_global_index
;
3190 gold_assert(sym_index
< output_count
);
3191 unsigned char* ps
= psyms
+ (sym_index
* sym_size
);
3192 this->sized_write_symbol
<size
, big_endian
>(sym
, sym_value
, shndx
,
3193 binding
, sympool
, ps
);
3196 if (dynsym_index
!= -1U)
3198 dynsym_index
-= first_dynamic_global_index
;
3199 gold_assert(dynsym_index
< dynamic_count
);
3200 unsigned char* pd
= dynamic_view
+ (dynsym_index
* sym_size
);
3201 this->sized_write_symbol
<size
, big_endian
>(sym
, dynsym_value
, shndx
,
3202 binding
, dynpool
, pd
);
3203 // Allow a target to adjust dynamic symbol value.
3204 parameters
->target().adjust_dyn_symbol(sym
, pd
);
3208 // Write the target-specific symbols.
3209 for (std::vector
<Symbol
*>::const_iterator p
= this->target_symbols_
.begin();
3210 p
!= this->target_symbols_
.end();
3213 Sized_symbol
<size
>* sym
= static_cast<Sized_symbol
<size
>*>(*p
);
3215 unsigned int sym_index
= sym
->symtab_index();
3216 unsigned int dynsym_index
;
3217 if (dynamic_view
== NULL
)
3220 dynsym_index
= sym
->dynsym_index();
3223 switch (sym
->source())
3225 case Symbol::IS_CONSTANT
:
3226 shndx
= elfcpp::SHN_ABS
;
3228 case Symbol::IS_UNDEFINED
:
3229 shndx
= elfcpp::SHN_UNDEF
;
3235 if (sym_index
!= -1U)
3237 sym_index
-= first_global_index
;
3238 gold_assert(sym_index
< output_count
);
3239 unsigned char* ps
= psyms
+ (sym_index
* sym_size
);
3240 this->sized_write_symbol
<size
, big_endian
>(sym
, sym
->value(), shndx
,
3241 sym
->binding(), sympool
,
3245 if (dynsym_index
!= -1U)
3247 dynsym_index
-= first_dynamic_global_index
;
3248 gold_assert(dynsym_index
< dynamic_count
);
3249 unsigned char* pd
= dynamic_view
+ (dynsym_index
* sym_size
);
3250 this->sized_write_symbol
<size
, big_endian
>(sym
, sym
->value(), shndx
,
3251 sym
->binding(), dynpool
,
3256 of
->write_output_view(this->offset_
, oview_size
, psyms
);
3257 if (dynamic_view
!= NULL
)
3258 of
->write_output_view(this->dynamic_offset_
, dynamic_size
, dynamic_view
);
3261 // Write out the symbol SYM, in section SHNDX, to P. POOL is the
3262 // strtab holding the name.
3264 template<int size
, bool big_endian
>
3266 Symbol_table::sized_write_symbol(
3267 Sized_symbol
<size
>* sym
,
3268 typename
elfcpp::Elf_types
<size
>::Elf_Addr value
,
3270 elfcpp::STB binding
,
3271 const Stringpool
* pool
,
3272 unsigned char* p
) const
3274 elfcpp::Sym_write
<size
, big_endian
> osym(p
);
3275 if (sym
->version() == NULL
|| !parameters
->options().relocatable())
3276 osym
.put_st_name(pool
->get_offset(sym
->name()));
3278 osym
.put_st_name(pool
->get_offset(sym
->versioned_name()));
3279 osym
.put_st_value(value
);
3280 // Use a symbol size of zero for undefined symbols from shared libraries.
3281 if (shndx
== elfcpp::SHN_UNDEF
&& sym
->is_from_dynobj())
3282 osym
.put_st_size(0);
3284 osym
.put_st_size(sym
->symsize());
3285 elfcpp::STT type
= sym
->type();
3286 gold_assert(type
!= elfcpp::STT_GNU_IFUNC
|| !sym
->is_from_dynobj());
3287 // A version script may have overridden the default binding.
3288 if (sym
->is_forced_local())
3289 osym
.put_st_info(elfcpp::elf_st_info(elfcpp::STB_LOCAL
, type
));
3291 osym
.put_st_info(elfcpp::elf_st_info(binding
, type
));
3292 osym
.put_st_other(elfcpp::elf_st_other(sym
->visibility(), sym
->nonvis()));
3293 osym
.put_st_shndx(shndx
);
3296 // Check for unresolved symbols in shared libraries. This is
3297 // controlled by the --allow-shlib-undefined option.
3299 // We only warn about libraries for which we have seen all the
3300 // DT_NEEDED entries. We don't try to track down DT_NEEDED entries
3301 // which were not seen in this link. If we didn't see a DT_NEEDED
3302 // entry, we aren't going to be able to reliably report whether the
3303 // symbol is undefined.
3305 // We also don't warn about libraries found in a system library
3306 // directory (e.g., /lib or /usr/lib); we assume that those libraries
3307 // are OK. This heuristic avoids problems on GNU/Linux, in which -ldl
3308 // can have undefined references satisfied by ld-linux.so.
3311 Symbol_table::warn_about_undefined_dynobj_symbol(Symbol
* sym
) const
3314 if (sym
->source() == Symbol::FROM_OBJECT
3315 && sym
->object()->is_dynamic()
3316 && sym
->shndx(&dummy
) == elfcpp::SHN_UNDEF
3317 && sym
->binding() != elfcpp::STB_WEAK
3318 && !parameters
->options().allow_shlib_undefined()
3319 && !parameters
->target().is_defined_by_abi(sym
)
3320 && !sym
->object()->is_in_system_directory())
3322 // A very ugly cast.
3323 Dynobj
* dynobj
= static_cast<Dynobj
*>(sym
->object());
3324 if (!dynobj
->has_unknown_needed_entries())
3325 gold_undefined_symbol(sym
);
3329 // Write out a section symbol. Return the update offset.
3332 Symbol_table::write_section_symbol(const Output_section
* os
,
3333 Output_symtab_xindex
* symtab_xindex
,
3337 switch (parameters
->size_and_endianness())
3339 #ifdef HAVE_TARGET_32_LITTLE
3340 case Parameters::TARGET_32_LITTLE
:
3341 this->sized_write_section_symbol
<32, false>(os
, symtab_xindex
, of
,
3345 #ifdef HAVE_TARGET_32_BIG
3346 case Parameters::TARGET_32_BIG
:
3347 this->sized_write_section_symbol
<32, true>(os
, symtab_xindex
, of
,
3351 #ifdef HAVE_TARGET_64_LITTLE
3352 case Parameters::TARGET_64_LITTLE
:
3353 this->sized_write_section_symbol
<64, false>(os
, symtab_xindex
, of
,
3357 #ifdef HAVE_TARGET_64_BIG
3358 case Parameters::TARGET_64_BIG
:
3359 this->sized_write_section_symbol
<64, true>(os
, symtab_xindex
, of
,
3368 // Write out a section symbol, specialized for size and endianness.
3370 template<int size
, bool big_endian
>
3372 Symbol_table::sized_write_section_symbol(const Output_section
* os
,
3373 Output_symtab_xindex
* symtab_xindex
,
3377 const int sym_size
= elfcpp::Elf_sizes
<size
>::sym_size
;
3379 unsigned char* pov
= of
->get_output_view(offset
, sym_size
);
3381 elfcpp::Sym_write
<size
, big_endian
> osym(pov
);
3382 osym
.put_st_name(0);
3383 if (parameters
->options().relocatable())
3384 osym
.put_st_value(0);
3386 osym
.put_st_value(os
->address());
3387 osym
.put_st_size(0);
3388 osym
.put_st_info(elfcpp::elf_st_info(elfcpp::STB_LOCAL
,
3389 elfcpp::STT_SECTION
));
3390 osym
.put_st_other(elfcpp::elf_st_other(elfcpp::STV_DEFAULT
, 0));
3392 unsigned int shndx
= os
->out_shndx();
3393 if (shndx
>= elfcpp::SHN_LORESERVE
)
3395 symtab_xindex
->add(os
->symtab_index(), shndx
);
3396 shndx
= elfcpp::SHN_XINDEX
;
3398 osym
.put_st_shndx(shndx
);
3400 of
->write_output_view(offset
, sym_size
, pov
);
3403 // Print statistical information to stderr. This is used for --stats.
3406 Symbol_table::print_stats() const
3408 #if defined(HAVE_TR1_UNORDERED_MAP) || defined(HAVE_EXT_HASH_MAP)
3409 fprintf(stderr
, _("%s: symbol table entries: %zu; buckets: %zu\n"),
3410 program_name
, this->table_
.size(), this->table_
.bucket_count());
3412 fprintf(stderr
, _("%s: symbol table entries: %zu\n"),
3413 program_name
, this->table_
.size());
3415 this->namepool_
.print_stats("symbol table stringpool");
3418 // We check for ODR violations by looking for symbols with the same
3419 // name for which the debugging information reports that they were
3420 // defined in disjoint source locations. When comparing the source
3421 // location, we consider instances with the same base filename to be
3422 // the same. This is because different object files/shared libraries
3423 // can include the same header file using different paths, and
3424 // different optimization settings can make the line number appear to
3425 // be a couple lines off, and we don't want to report an ODR violation
3428 // This struct is used to compare line information, as returned by
3429 // Dwarf_line_info::one_addr2line. It implements a < comparison
3430 // operator used with std::sort.
3432 struct Odr_violation_compare
3435 operator()(const std::string
& s1
, const std::string
& s2
) const
3437 // Inputs should be of the form "dirname/filename:linenum" where
3438 // "dirname/" is optional. We want to compare just the filename:linenum.
3440 // Find the last '/' in each string.
3441 std::string::size_type s1begin
= s1
.rfind('/');
3442 std::string::size_type s2begin
= s2
.rfind('/');
3443 // If there was no '/' in a string, start at the beginning.
3444 if (s1begin
== std::string::npos
)
3446 if (s2begin
== std::string::npos
)
3448 return s1
.compare(s1begin
, std::string::npos
,
3449 s2
, s2begin
, std::string::npos
) < 0;
3453 // Returns all of the lines attached to LOC, not just the one the
3454 // instruction actually came from.
3455 std::vector
<std::string
>
3456 Symbol_table::linenos_from_loc(const Task
* task
,
3457 const Symbol_location
& loc
)
3459 // We need to lock the object in order to read it. This
3460 // means that we have to run in a singleton Task. If we
3461 // want to run this in a general Task for better
3462 // performance, we will need one Task for object, plus
3463 // appropriate locking to ensure that we don't conflict with
3464 // other uses of the object. Also note, one_addr2line is not
3465 // currently thread-safe.
3466 Task_lock_obj
<Object
> tl(task
, loc
.object
);
3468 std::vector
<std::string
> result
;
3469 Symbol_location code_loc
= loc
;
3470 parameters
->target().function_location(&code_loc
);
3471 // 16 is the size of the object-cache that one_addr2line should use.
3472 std::string canonical_result
= Dwarf_line_info::one_addr2line(
3473 code_loc
.object
, code_loc
.shndx
, code_loc
.offset
, 16, &result
);
3474 if (!canonical_result
.empty())
3475 result
.push_back(canonical_result
);
3479 // OutputIterator that records if it was ever assigned to. This
3480 // allows it to be used with std::set_intersection() to check for
3481 // intersection rather than computing the intersection.
3482 struct Check_intersection
3484 Check_intersection()
3488 bool had_intersection() const
3489 { return this->value_
; }
3491 Check_intersection
& operator++()
3494 Check_intersection
& operator*()
3497 template<typename T
>
3498 Check_intersection
& operator=(const T
&)
3500 this->value_
= true;
3508 // Check candidate_odr_violations_ to find symbols with the same name
3509 // but apparently different definitions (different source-file/line-no
3510 // for each line assigned to the first instruction).
3513 Symbol_table::detect_odr_violations(const Task
* task
,
3514 const char* output_file_name
) const
3516 for (Odr_map::const_iterator it
= candidate_odr_violations_
.begin();
3517 it
!= candidate_odr_violations_
.end();
3520 const char* const symbol_name
= it
->first
;
3522 std::string first_object_name
;
3523 std::vector
<std::string
> first_object_linenos
;
3525 Unordered_set
<Symbol_location
, Symbol_location_hash
>::const_iterator
3526 locs
= it
->second
.begin();
3527 const Unordered_set
<Symbol_location
, Symbol_location_hash
>::const_iterator
3528 locs_end
= it
->second
.end();
3529 for (; locs
!= locs_end
&& first_object_linenos
.empty(); ++locs
)
3531 // Save the line numbers from the first definition to
3532 // compare to the other definitions. Ideally, we'd compare
3533 // every definition to every other, but we don't want to
3534 // take O(N^2) time to do this. This shortcut may cause
3535 // false negatives that appear or disappear depending on the
3536 // link order, but it won't cause false positives.
3537 first_object_name
= locs
->object
->name();
3538 first_object_linenos
= this->linenos_from_loc(task
, *locs
);
3540 if (first_object_linenos
.empty())
3543 // Sort by Odr_violation_compare to make std::set_intersection work.
3544 std::string first_object_canonical_result
= first_object_linenos
.back();
3545 std::sort(first_object_linenos
.begin(), first_object_linenos
.end(),
3546 Odr_violation_compare());
3548 for (; locs
!= locs_end
; ++locs
)
3550 std::vector
<std::string
> linenos
=
3551 this->linenos_from_loc(task
, *locs
);
3552 // linenos will be empty if we couldn't parse the debug info.
3553 if (linenos
.empty())
3555 // Sort by Odr_violation_compare to make std::set_intersection work.
3556 gold_assert(!linenos
.empty());
3557 std::string second_object_canonical_result
= linenos
.back();
3558 std::sort(linenos
.begin(), linenos
.end(), Odr_violation_compare());
3560 Check_intersection intersection_result
=
3561 std::set_intersection(first_object_linenos
.begin(),
3562 first_object_linenos
.end(),
3565 Check_intersection(),
3566 Odr_violation_compare());
3567 if (!intersection_result
.had_intersection())
3569 gold_warning(_("while linking %s: symbol '%s' defined in "
3570 "multiple places (possible ODR violation):"),
3571 output_file_name
, demangle(symbol_name
).c_str());
3572 // This only prints one location from each definition,
3573 // which may not be the location we expect to intersect
3574 // with another definition. We could print the whole
3575 // set of locations, but that seems too verbose.
3576 fprintf(stderr
, _(" %s from %s\n"),
3577 first_object_canonical_result
.c_str(),
3578 first_object_name
.c_str());
3579 fprintf(stderr
, _(" %s from %s\n"),
3580 second_object_canonical_result
.c_str(),
3581 locs
->object
->name().c_str());
3582 // Only print one broken pair, to avoid needing to
3583 // compare against a list of the disjoint definition
3584 // locations we've found so far. (If we kept comparing
3585 // against just the first one, we'd get a lot of
3586 // redundant complaints about the second definition
3592 // We only call one_addr2line() in this function, so we can clear its cache.
3593 Dwarf_line_info::clear_addr2line_cache();
3596 // Warnings functions.
3598 // Add a new warning.
3601 Warnings::add_warning(Symbol_table
* symtab
, const char* name
, Object
* obj
,
3602 const std::string
& warning
)
3604 name
= symtab
->canonicalize_name(name
);
3605 this->warnings_
[name
].set(obj
, warning
);
3608 // Look through the warnings and mark the symbols for which we should
3609 // warn. This is called during Layout::finalize when we know the
3610 // sources for all the symbols.
3613 Warnings::note_warnings(Symbol_table
* symtab
)
3615 for (Warning_table::iterator p
= this->warnings_
.begin();
3616 p
!= this->warnings_
.end();
3619 Symbol
* sym
= symtab
->lookup(p
->first
, NULL
);
3621 && sym
->source() == Symbol::FROM_OBJECT
3622 && sym
->object() == p
->second
.object
)
3623 sym
->set_has_warning();
3627 // Issue a warning. This is called when we see a relocation against a
3628 // symbol for which has a warning.
3630 template<int size
, bool big_endian
>
3632 Warnings::issue_warning(const Symbol
* sym
,
3633 const Relocate_info
<size
, big_endian
>* relinfo
,
3634 size_t relnum
, off_t reloffset
) const
3636 gold_assert(sym
->has_warning());
3638 // We don't want to issue a warning for a relocation against the
3639 // symbol in the same object file in which the symbol is defined.
3640 if (sym
->object() == relinfo
->object
)
3643 Warning_table::const_iterator p
= this->warnings_
.find(sym
->name());
3644 gold_assert(p
!= this->warnings_
.end());
3645 gold_warning_at_location(relinfo
, relnum
, reloffset
,
3646 "%s", p
->second
.text
.c_str());
3649 // Instantiate the templates we need. We could use the configure
3650 // script to restrict this to only the ones needed for implemented
3653 #if defined(HAVE_TARGET_32_LITTLE) || defined(HAVE_TARGET_32_BIG)
3656 Sized_symbol
<32>::allocate_common(Output_data
*, Value_type
);
3659 #if defined(HAVE_TARGET_64_LITTLE) || defined(HAVE_TARGET_64_BIG)
3662 Sized_symbol
<64>::allocate_common(Output_data
*, Value_type
);
3665 #ifdef HAVE_TARGET_32_LITTLE
3668 Symbol_table::add_from_relobj
<32, false>(
3669 Sized_relobj_file
<32, false>* relobj
,
3670 const unsigned char* syms
,
3672 size_t symndx_offset
,
3673 const char* sym_names
,
3674 size_t sym_name_size
,
3675 Sized_relobj_file
<32, false>::Symbols
* sympointers
,
3679 #ifdef HAVE_TARGET_32_BIG
3682 Symbol_table::add_from_relobj
<32, true>(
3683 Sized_relobj_file
<32, true>* relobj
,
3684 const unsigned char* syms
,
3686 size_t symndx_offset
,
3687 const char* sym_names
,
3688 size_t sym_name_size
,
3689 Sized_relobj_file
<32, true>::Symbols
* sympointers
,
3693 #ifdef HAVE_TARGET_64_LITTLE
3696 Symbol_table::add_from_relobj
<64, false>(
3697 Sized_relobj_file
<64, false>* relobj
,
3698 const unsigned char* syms
,
3700 size_t symndx_offset
,
3701 const char* sym_names
,
3702 size_t sym_name_size
,
3703 Sized_relobj_file
<64, false>::Symbols
* sympointers
,
3707 #ifdef HAVE_TARGET_64_BIG
3710 Symbol_table::add_from_relobj
<64, true>(
3711 Sized_relobj_file
<64, true>* relobj
,
3712 const unsigned char* syms
,
3714 size_t symndx_offset
,
3715 const char* sym_names
,
3716 size_t sym_name_size
,
3717 Sized_relobj_file
<64, true>::Symbols
* sympointers
,
3721 #ifdef HAVE_TARGET_32_LITTLE
3724 Symbol_table::add_from_pluginobj
<32, false>(
3725 Sized_pluginobj
<32, false>* obj
,
3728 elfcpp::Sym
<32, false>* sym
);
3731 #ifdef HAVE_TARGET_32_BIG
3734 Symbol_table::add_from_pluginobj
<32, true>(
3735 Sized_pluginobj
<32, true>* obj
,
3738 elfcpp::Sym
<32, true>* sym
);
3741 #ifdef HAVE_TARGET_64_LITTLE
3744 Symbol_table::add_from_pluginobj
<64, false>(
3745 Sized_pluginobj
<64, false>* obj
,
3748 elfcpp::Sym
<64, false>* sym
);
3751 #ifdef HAVE_TARGET_64_BIG
3754 Symbol_table::add_from_pluginobj
<64, true>(
3755 Sized_pluginobj
<64, true>* obj
,
3758 elfcpp::Sym
<64, true>* sym
);
3761 #ifdef HAVE_TARGET_32_LITTLE
3764 Symbol_table::add_from_dynobj
<32, false>(
3765 Sized_dynobj
<32, false>* dynobj
,
3766 const unsigned char* syms
,
3768 const char* sym_names
,
3769 size_t sym_name_size
,
3770 const unsigned char* versym
,
3772 const std::vector
<const char*>* version_map
,
3773 Sized_relobj_file
<32, false>::Symbols
* sympointers
,
3777 #ifdef HAVE_TARGET_32_BIG
3780 Symbol_table::add_from_dynobj
<32, true>(
3781 Sized_dynobj
<32, true>* dynobj
,
3782 const unsigned char* syms
,
3784 const char* sym_names
,
3785 size_t sym_name_size
,
3786 const unsigned char* versym
,
3788 const std::vector
<const char*>* version_map
,
3789 Sized_relobj_file
<32, true>::Symbols
* sympointers
,
3793 #ifdef HAVE_TARGET_64_LITTLE
3796 Symbol_table::add_from_dynobj
<64, false>(
3797 Sized_dynobj
<64, false>* dynobj
,
3798 const unsigned char* syms
,
3800 const char* sym_names
,
3801 size_t sym_name_size
,
3802 const unsigned char* versym
,
3804 const std::vector
<const char*>* version_map
,
3805 Sized_relobj_file
<64, false>::Symbols
* sympointers
,
3809 #ifdef HAVE_TARGET_64_BIG
3812 Symbol_table::add_from_dynobj
<64, true>(
3813 Sized_dynobj
<64, true>* dynobj
,
3814 const unsigned char* syms
,
3816 const char* sym_names
,
3817 size_t sym_name_size
,
3818 const unsigned char* versym
,
3820 const std::vector
<const char*>* version_map
,
3821 Sized_relobj_file
<64, true>::Symbols
* sympointers
,
3825 #ifdef HAVE_TARGET_32_LITTLE
3828 Symbol_table::add_from_incrobj(
3832 elfcpp::Sym
<32, false>* sym
);
3835 #ifdef HAVE_TARGET_32_BIG
3838 Symbol_table::add_from_incrobj(
3842 elfcpp::Sym
<32, true>* sym
);
3845 #ifdef HAVE_TARGET_64_LITTLE
3848 Symbol_table::add_from_incrobj(
3852 elfcpp::Sym
<64, false>* sym
);
3855 #ifdef HAVE_TARGET_64_BIG
3858 Symbol_table::add_from_incrobj(
3862 elfcpp::Sym
<64, true>* sym
);
3865 #if defined(HAVE_TARGET_32_LITTLE) || defined(HAVE_TARGET_32_BIG)
3868 Symbol_table::define_with_copy_reloc
<32>(
3869 Sized_symbol
<32>* sym
,
3871 elfcpp::Elf_types
<32>::Elf_Addr value
);
3874 #if defined(HAVE_TARGET_64_LITTLE) || defined(HAVE_TARGET_64_BIG)
3877 Symbol_table::define_with_copy_reloc
<64>(
3878 Sized_symbol
<64>* sym
,
3880 elfcpp::Elf_types
<64>::Elf_Addr value
);
3883 #if defined(HAVE_TARGET_32_LITTLE) || defined(HAVE_TARGET_32_BIG)
3886 Sized_symbol
<32>::init_output_data(const char* name
, const char* version
,
3887 Output_data
* od
, Value_type value
,
3888 Size_type symsize
, elfcpp::STT type
,
3889 elfcpp::STB binding
,
3890 elfcpp::STV visibility
,
3891 unsigned char nonvis
,
3892 bool offset_is_from_end
,
3893 bool is_predefined
);
3897 Sized_symbol
<32>::init_constant(const char* name
, const char* version
,
3898 Value_type value
, Size_type symsize
,
3899 elfcpp::STT type
, elfcpp::STB binding
,
3900 elfcpp::STV visibility
, unsigned char nonvis
,
3901 bool is_predefined
);
3905 Sized_symbol
<32>::init_undefined(const char* name
, const char* version
,
3906 Value_type value
, elfcpp::STT type
,
3907 elfcpp::STB binding
, elfcpp::STV visibility
,
3908 unsigned char nonvis
);
3911 #if defined(HAVE_TARGET_64_LITTLE) || defined(HAVE_TARGET_64_BIG)
3914 Sized_symbol
<64>::init_output_data(const char* name
, const char* version
,
3915 Output_data
* od
, Value_type value
,
3916 Size_type symsize
, elfcpp::STT type
,
3917 elfcpp::STB binding
,
3918 elfcpp::STV visibility
,
3919 unsigned char nonvis
,
3920 bool offset_is_from_end
,
3921 bool is_predefined
);
3925 Sized_symbol
<64>::init_constant(const char* name
, const char* version
,
3926 Value_type value
, Size_type symsize
,
3927 elfcpp::STT type
, elfcpp::STB binding
,
3928 elfcpp::STV visibility
, unsigned char nonvis
,
3929 bool is_predefined
);
3933 Sized_symbol
<64>::init_undefined(const char* name
, const char* version
,
3934 Value_type value
, elfcpp::STT type
,
3935 elfcpp::STB binding
, elfcpp::STV visibility
,
3936 unsigned char nonvis
);
3939 #ifdef HAVE_TARGET_32_LITTLE
3942 Warnings::issue_warning
<32, false>(const Symbol
* sym
,
3943 const Relocate_info
<32, false>* relinfo
,
3944 size_t relnum
, off_t reloffset
) const;
3947 #ifdef HAVE_TARGET_32_BIG
3950 Warnings::issue_warning
<32, true>(const Symbol
* sym
,
3951 const Relocate_info
<32, true>* relinfo
,
3952 size_t relnum
, off_t reloffset
) const;
3955 #ifdef HAVE_TARGET_64_LITTLE
3958 Warnings::issue_warning
<64, false>(const Symbol
* sym
,
3959 const Relocate_info
<64, false>* relinfo
,
3960 size_t relnum
, off_t reloffset
) const;
3963 #ifdef HAVE_TARGET_64_BIG
3966 Warnings::issue_warning
<64, true>(const Symbol
* sym
,
3967 const Relocate_info
<64, true>* relinfo
,
3968 size_t relnum
, off_t reloffset
) const;
3971 } // End namespace gold.