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()
1188 && strcmp (name
, "__gnu_lto_slim") == 0)
1189 gold_info(_("%s: plugin needed to handle lto object"),
1190 relobj
->name().c_str());
1193 unsigned int st_shndx
= relobj
->adjust_sym_shndx(i
+ symndx_offset
,
1196 unsigned int orig_st_shndx
= st_shndx
;
1198 orig_st_shndx
= elfcpp::SHN_UNDEF
;
1200 if (st_shndx
!= elfcpp::SHN_UNDEF
)
1203 // A symbol defined in a section which we are not including must
1204 // be treated as an undefined symbol.
1205 bool is_defined_in_discarded_section
= false;
1206 if (st_shndx
!= elfcpp::SHN_UNDEF
1208 && !relobj
->is_section_included(st_shndx
)
1209 && !this->is_section_folded(relobj
, st_shndx
))
1211 st_shndx
= elfcpp::SHN_UNDEF
;
1212 is_defined_in_discarded_section
= true;
1215 // In an object file, an '@' in the name separates the symbol
1216 // name from the version name. If there are two '@' characters,
1217 // this is the default version.
1218 const char* ver
= strchr(name
, '@');
1219 Stringpool::Key ver_key
= 0;
1221 // IS_DEFAULT_VERSION: is the version default?
1222 // IS_FORCED_LOCAL: is the symbol forced local?
1223 bool is_default_version
= false;
1224 bool is_forced_local
= false;
1226 // FIXME: For incremental links, we don't store version information,
1227 // so we need to ignore version symbols for now.
1228 if (parameters
->incremental_update() && ver
!= NULL
)
1230 namelen
= ver
- name
;
1236 // The symbol name is of the form foo@VERSION or foo@@VERSION
1237 namelen
= ver
- name
;
1241 is_default_version
= true;
1244 ver
= this->namepool_
.add(ver
, true, &ver_key
);
1246 // We don't want to assign a version to an undefined symbol,
1247 // even if it is listed in the version script. FIXME: What
1248 // about a common symbol?
1251 namelen
= strlen(name
);
1252 if (!this->version_script_
.empty()
1253 && st_shndx
!= elfcpp::SHN_UNDEF
)
1255 // The symbol name did not have a version, but the
1256 // version script may assign a version anyway.
1257 std::string version
;
1259 if (this->version_script_
.get_symbol_version(name
, &version
,
1263 is_forced_local
= true;
1264 else if (!version
.empty())
1266 ver
= this->namepool_
.add_with_length(version
.c_str(),
1270 is_default_version
= true;
1276 elfcpp::Sym
<size
, big_endian
>* psym
= &sym
;
1277 unsigned char symbuf
[sym_size
];
1278 elfcpp::Sym
<size
, big_endian
> sym2(symbuf
);
1281 memcpy(symbuf
, p
, sym_size
);
1282 elfcpp::Sym_write
<size
, big_endian
> sw(symbuf
);
1283 if (orig_st_shndx
!= elfcpp::SHN_UNDEF
1285 && relobj
->e_type() == elfcpp::ET_REL
)
1287 // Symbol values in relocatable object files are section
1288 // relative. This is normally what we want, but since here
1289 // we are converting the symbol to absolute we need to add
1290 // the section address. The section address in an object
1291 // file is normally zero, but people can use a linker
1292 // script to change it.
1293 sw
.put_st_value(sym
.get_st_value()
1294 + relobj
->section_address(orig_st_shndx
));
1296 st_shndx
= elfcpp::SHN_ABS
;
1297 is_ordinary
= false;
1301 // Fix up visibility if object has no-export set.
1302 if (relobj
->no_export()
1303 && (orig_st_shndx
!= elfcpp::SHN_UNDEF
|| !is_ordinary
))
1305 // We may have copied symbol already above.
1308 memcpy(symbuf
, p
, sym_size
);
1312 elfcpp::STV visibility
= sym2
.get_st_visibility();
1313 if (visibility
== elfcpp::STV_DEFAULT
1314 || visibility
== elfcpp::STV_PROTECTED
)
1316 elfcpp::Sym_write
<size
, big_endian
> sw(symbuf
);
1317 unsigned char nonvis
= sym2
.get_st_nonvis();
1318 sw
.put_st_other(elfcpp::STV_HIDDEN
, nonvis
);
1322 Stringpool::Key name_key
;
1323 name
= this->namepool_
.add_with_length(name
, namelen
, true,
1326 Sized_symbol
<size
>* res
;
1327 res
= this->add_from_object(relobj
, name
, name_key
, ver
, ver_key
,
1328 is_default_version
, *psym
, st_shndx
,
1329 is_ordinary
, orig_st_shndx
);
1334 if (is_forced_local
)
1335 this->force_local(res
);
1337 // Do not treat this symbol as garbage if this symbol will be
1338 // exported to the dynamic symbol table. This is true when
1339 // building a shared library or using --export-dynamic and
1340 // the symbol is externally visible.
1341 if (parameters
->options().gc_sections()
1342 && res
->is_externally_visible()
1343 && !res
->is_from_dynobj()
1344 && (parameters
->options().shared()
1345 || parameters
->options().export_dynamic()
1346 || parameters
->options().in_dynamic_list(res
->name())))
1347 this->gc_mark_symbol(res
);
1349 if (is_defined_in_discarded_section
)
1350 res
->set_is_defined_in_discarded_section();
1352 (*sympointers
)[i
] = res
;
1356 // Add a symbol from a plugin-claimed file.
1358 template<int size
, bool big_endian
>
1360 Symbol_table::add_from_pluginobj(
1361 Sized_pluginobj
<size
, big_endian
>* obj
,
1364 elfcpp::Sym
<size
, big_endian
>* sym
)
1366 unsigned int st_shndx
= sym
->get_st_shndx();
1367 bool is_ordinary
= st_shndx
< elfcpp::SHN_LORESERVE
;
1369 Stringpool::Key ver_key
= 0;
1370 bool is_default_version
= false;
1371 bool is_forced_local
= false;
1375 ver
= this->namepool_
.add(ver
, true, &ver_key
);
1377 // We don't want to assign a version to an undefined symbol,
1378 // even if it is listed in the version script. FIXME: What
1379 // about a common symbol?
1382 if (!this->version_script_
.empty()
1383 && st_shndx
!= elfcpp::SHN_UNDEF
)
1385 // The symbol name did not have a version, but the
1386 // version script may assign a version anyway.
1387 std::string version
;
1389 if (this->version_script_
.get_symbol_version(name
, &version
,
1393 is_forced_local
= true;
1394 else if (!version
.empty())
1396 ver
= this->namepool_
.add_with_length(version
.c_str(),
1400 is_default_version
= true;
1406 Stringpool::Key name_key
;
1407 name
= this->namepool_
.add(name
, true, &name_key
);
1409 Sized_symbol
<size
>* res
;
1410 res
= this->add_from_object(obj
, name
, name_key
, ver
, ver_key
,
1411 is_default_version
, *sym
, st_shndx
,
1412 is_ordinary
, st_shndx
);
1417 if (is_forced_local
)
1418 this->force_local(res
);
1423 // Add all the symbols in a dynamic object to the hash table.
1425 template<int size
, bool big_endian
>
1427 Symbol_table::add_from_dynobj(
1428 Sized_dynobj
<size
, big_endian
>* dynobj
,
1429 const unsigned char* syms
,
1431 const char* sym_names
,
1432 size_t sym_name_size
,
1433 const unsigned char* versym
,
1435 const std::vector
<const char*>* version_map
,
1436 typename Sized_relobj_file
<size
, big_endian
>::Symbols
* sympointers
,
1441 gold_assert(size
== parameters
->target().get_size());
1443 if (dynobj
->just_symbols())
1445 gold_error(_("--just-symbols does not make sense with a shared object"));
1449 // FIXME: For incremental links, we don't store version information,
1450 // so we need to ignore version symbols for now.
1451 if (parameters
->incremental_update())
1454 if (versym
!= NULL
&& versym_size
/ 2 < count
)
1456 dynobj
->error(_("too few symbol versions"));
1460 const int sym_size
= elfcpp::Elf_sizes
<size
>::sym_size
;
1462 // We keep a list of all STT_OBJECT symbols, so that we can resolve
1463 // weak aliases. This is necessary because if the dynamic object
1464 // provides the same variable under two names, one of which is a
1465 // weak definition, and the regular object refers to the weak
1466 // definition, we have to put both the weak definition and the
1467 // strong definition into the dynamic symbol table. Given a weak
1468 // definition, the only way that we can find the corresponding
1469 // strong definition, if any, is to search the symbol table.
1470 std::vector
<Sized_symbol
<size
>*> object_symbols
;
1472 const unsigned char* p
= syms
;
1473 const unsigned char* vs
= versym
;
1474 for (size_t i
= 0; i
< count
; ++i
, p
+= sym_size
, vs
+= 2)
1476 elfcpp::Sym
<size
, big_endian
> sym(p
);
1478 if (sympointers
!= NULL
)
1479 (*sympointers
)[i
] = NULL
;
1481 // Ignore symbols with local binding or that have
1482 // internal or hidden visibility.
1483 if (sym
.get_st_bind() == elfcpp::STB_LOCAL
1484 || sym
.get_st_visibility() == elfcpp::STV_INTERNAL
1485 || sym
.get_st_visibility() == elfcpp::STV_HIDDEN
)
1488 // A protected symbol in a shared library must be treated as a
1489 // normal symbol when viewed from outside the shared library.
1490 // Implement this by overriding the visibility here.
1491 // Likewise, an IFUNC symbol in a shared library must be treated
1492 // as a normal FUNC symbol.
1493 elfcpp::Sym
<size
, big_endian
>* psym
= &sym
;
1494 unsigned char symbuf
[sym_size
];
1495 elfcpp::Sym
<size
, big_endian
> sym2(symbuf
);
1496 if (sym
.get_st_visibility() == elfcpp::STV_PROTECTED
1497 || sym
.get_st_type() == elfcpp::STT_GNU_IFUNC
)
1499 memcpy(symbuf
, p
, sym_size
);
1500 elfcpp::Sym_write
<size
, big_endian
> sw(symbuf
);
1501 if (sym
.get_st_visibility() == elfcpp::STV_PROTECTED
)
1502 sw
.put_st_other(elfcpp::STV_DEFAULT
, sym
.get_st_nonvis());
1503 if (sym
.get_st_type() == elfcpp::STT_GNU_IFUNC
)
1504 sw
.put_st_info(sym
.get_st_bind(), elfcpp::STT_FUNC
);
1508 unsigned int st_name
= psym
->get_st_name();
1509 if (st_name
>= sym_name_size
)
1511 dynobj
->error(_("bad symbol name offset %u at %zu"),
1516 const char* name
= sym_names
+ st_name
;
1519 unsigned int st_shndx
= dynobj
->adjust_sym_shndx(i
, psym
->get_st_shndx(),
1522 if (st_shndx
!= elfcpp::SHN_UNDEF
)
1525 Sized_symbol
<size
>* res
;
1529 Stringpool::Key name_key
;
1530 name
= this->namepool_
.add(name
, true, &name_key
);
1531 res
= this->add_from_object(dynobj
, name
, name_key
, NULL
, 0,
1532 false, *psym
, st_shndx
, is_ordinary
,
1537 // Read the version information.
1539 unsigned int v
= elfcpp::Swap
<16, big_endian
>::readval(vs
);
1541 bool hidden
= (v
& elfcpp::VERSYM_HIDDEN
) != 0;
1542 v
&= elfcpp::VERSYM_VERSION
;
1544 // The Sun documentation says that V can be VER_NDX_LOCAL,
1545 // or VER_NDX_GLOBAL, or a version index. The meaning of
1546 // VER_NDX_LOCAL is defined as "Symbol has local scope."
1547 // The old GNU linker will happily generate VER_NDX_LOCAL
1548 // for an undefined symbol. I don't know what the Sun
1549 // linker will generate.
1551 if (v
== static_cast<unsigned int>(elfcpp::VER_NDX_LOCAL
)
1552 && st_shndx
!= elfcpp::SHN_UNDEF
)
1554 // This symbol should not be visible outside the object.
1558 // At this point we are definitely going to add this symbol.
1559 Stringpool::Key name_key
;
1560 name
= this->namepool_
.add(name
, true, &name_key
);
1562 if (v
== static_cast<unsigned int>(elfcpp::VER_NDX_LOCAL
)
1563 || v
== static_cast<unsigned int>(elfcpp::VER_NDX_GLOBAL
))
1565 // This symbol does not have a version.
1566 res
= this->add_from_object(dynobj
, name
, name_key
, NULL
, 0,
1567 false, *psym
, st_shndx
, is_ordinary
,
1572 if (v
>= version_map
->size())
1574 dynobj
->error(_("versym for symbol %zu out of range: %u"),
1579 const char* version
= (*version_map
)[v
];
1580 if (version
== NULL
)
1582 dynobj
->error(_("versym for symbol %zu has no name: %u"),
1587 Stringpool::Key version_key
;
1588 version
= this->namepool_
.add(version
, true, &version_key
);
1590 // If this is an absolute symbol, and the version name
1591 // and symbol name are the same, then this is the
1592 // version definition symbol. These symbols exist to
1593 // support using -u to pull in particular versions. We
1594 // do not want to record a version for them.
1595 if (st_shndx
== elfcpp::SHN_ABS
1597 && name_key
== version_key
)
1598 res
= this->add_from_object(dynobj
, name
, name_key
, NULL
, 0,
1599 false, *psym
, st_shndx
, is_ordinary
,
1603 const bool is_default_version
=
1604 !hidden
&& st_shndx
!= elfcpp::SHN_UNDEF
;
1605 res
= this->add_from_object(dynobj
, name
, name_key
, version
,
1606 version_key
, is_default_version
,
1608 is_ordinary
, st_shndx
);
1616 // Note that it is possible that RES was overridden by an
1617 // earlier object, in which case it can't be aliased here.
1618 if (st_shndx
!= elfcpp::SHN_UNDEF
1620 && psym
->get_st_type() == elfcpp::STT_OBJECT
1621 && res
->source() == Symbol::FROM_OBJECT
1622 && res
->object() == dynobj
)
1623 object_symbols
.push_back(res
);
1625 // If the symbol has protected visibility in the dynobj,
1626 // mark it as such if it was not overridden.
1627 if (res
->source() == Symbol::FROM_OBJECT
1628 && res
->object() == dynobj
1629 && sym
.get_st_visibility() == elfcpp::STV_PROTECTED
)
1630 res
->set_is_protected();
1632 if (sympointers
!= NULL
)
1633 (*sympointers
)[i
] = res
;
1636 this->record_weak_aliases(&object_symbols
);
1639 // Add a symbol from a incremental object file.
1641 template<int size
, bool big_endian
>
1643 Symbol_table::add_from_incrobj(
1647 elfcpp::Sym
<size
, big_endian
>* sym
)
1649 unsigned int st_shndx
= sym
->get_st_shndx();
1650 bool is_ordinary
= st_shndx
< elfcpp::SHN_LORESERVE
;
1652 Stringpool::Key ver_key
= 0;
1653 bool is_default_version
= false;
1655 Stringpool::Key name_key
;
1656 name
= this->namepool_
.add(name
, true, &name_key
);
1658 Sized_symbol
<size
>* res
;
1659 res
= this->add_from_object(obj
, name
, name_key
, ver
, ver_key
,
1660 is_default_version
, *sym
, st_shndx
,
1661 is_ordinary
, st_shndx
);
1666 // This is used to sort weak aliases. We sort them first by section
1667 // index, then by offset, then by weak ahead of strong.
1670 class Weak_alias_sorter
1673 bool operator()(const Sized_symbol
<size
>*, const Sized_symbol
<size
>*) const;
1678 Weak_alias_sorter
<size
>::operator()(const Sized_symbol
<size
>* s1
,
1679 const Sized_symbol
<size
>* s2
) const
1682 unsigned int s1_shndx
= s1
->shndx(&is_ordinary
);
1683 gold_assert(is_ordinary
);
1684 unsigned int s2_shndx
= s2
->shndx(&is_ordinary
);
1685 gold_assert(is_ordinary
);
1686 if (s1_shndx
!= s2_shndx
)
1687 return s1_shndx
< s2_shndx
;
1689 if (s1
->value() != s2
->value())
1690 return s1
->value() < s2
->value();
1691 if (s1
->binding() != s2
->binding())
1693 if (s1
->binding() == elfcpp::STB_WEAK
)
1695 if (s2
->binding() == elfcpp::STB_WEAK
)
1698 return std::string(s1
->name()) < std::string(s2
->name());
1701 // SYMBOLS is a list of object symbols from a dynamic object. Look
1702 // for any weak aliases, and record them so that if we add the weak
1703 // alias to the dynamic symbol table, we also add the corresponding
1708 Symbol_table::record_weak_aliases(std::vector
<Sized_symbol
<size
>*>* symbols
)
1710 // Sort the vector by section index, then by offset, then by weak
1712 std::sort(symbols
->begin(), symbols
->end(), Weak_alias_sorter
<size
>());
1714 // Walk through the vector. For each weak definition, record
1716 for (typename
std::vector
<Sized_symbol
<size
>*>::const_iterator p
=
1718 p
!= symbols
->end();
1721 if ((*p
)->binding() != elfcpp::STB_WEAK
)
1724 // Build a circular list of weak aliases. Each symbol points to
1725 // the next one in the circular list.
1727 Sized_symbol
<size
>* from_sym
= *p
;
1728 typename
std::vector
<Sized_symbol
<size
>*>::const_iterator q
;
1729 for (q
= p
+ 1; q
!= symbols
->end(); ++q
)
1732 if ((*q
)->shndx(&dummy
) != from_sym
->shndx(&dummy
)
1733 || (*q
)->value() != from_sym
->value())
1736 this->weak_aliases_
[from_sym
] = *q
;
1737 from_sym
->set_has_alias();
1743 this->weak_aliases_
[from_sym
] = *p
;
1744 from_sym
->set_has_alias();
1751 // Create and return a specially defined symbol. If ONLY_IF_REF is
1752 // true, then only create the symbol if there is a reference to it.
1753 // If this does not return NULL, it sets *POLDSYM to the existing
1754 // symbol if there is one. This sets *RESOLVE_OLDSYM if we should
1755 // resolve the newly created symbol to the old one. This
1756 // canonicalizes *PNAME and *PVERSION.
1758 template<int size
, bool big_endian
>
1760 Symbol_table::define_special_symbol(const char** pname
, const char** pversion
,
1762 Sized_symbol
<size
>** poldsym
,
1763 bool* resolve_oldsym
, bool is_forced_local
)
1765 *resolve_oldsym
= false;
1768 // If the caller didn't give us a version, see if we get one from
1769 // the version script.
1771 bool is_default_version
= false;
1772 if (!is_forced_local
&& *pversion
== NULL
)
1775 if (this->version_script_
.get_symbol_version(*pname
, &v
, &is_global
))
1777 if (is_global
&& !v
.empty())
1779 *pversion
= v
.c_str();
1780 // If we get the version from a version script, then we
1781 // are also the default version.
1782 is_default_version
= true;
1788 Sized_symbol
<size
>* sym
;
1790 bool add_to_table
= false;
1791 typename
Symbol_table_type::iterator add_loc
= this->table_
.end();
1792 bool add_def_to_table
= false;
1793 typename
Symbol_table_type::iterator add_def_loc
= this->table_
.end();
1797 oldsym
= this->lookup(*pname
, *pversion
);
1798 if (oldsym
== NULL
&& is_default_version
)
1799 oldsym
= this->lookup(*pname
, NULL
);
1800 if (oldsym
== NULL
|| !oldsym
->is_undefined())
1803 *pname
= oldsym
->name();
1804 if (is_default_version
)
1805 *pversion
= this->namepool_
.add(*pversion
, true, NULL
);
1807 *pversion
= oldsym
->version();
1811 // Canonicalize NAME and VERSION.
1812 Stringpool::Key name_key
;
1813 *pname
= this->namepool_
.add(*pname
, true, &name_key
);
1815 Stringpool::Key version_key
= 0;
1816 if (*pversion
!= NULL
)
1817 *pversion
= this->namepool_
.add(*pversion
, true, &version_key
);
1819 Symbol
* const snull
= NULL
;
1820 std::pair
<typename
Symbol_table_type::iterator
, bool> ins
=
1821 this->table_
.insert(std::make_pair(std::make_pair(name_key
,
1825 std::pair
<typename
Symbol_table_type::iterator
, bool> insdefault
=
1826 std::make_pair(this->table_
.end(), false);
1827 if (is_default_version
)
1829 const Stringpool::Key vnull
= 0;
1831 this->table_
.insert(std::make_pair(std::make_pair(name_key
,
1838 // We already have a symbol table entry for NAME/VERSION.
1839 oldsym
= ins
.first
->second
;
1840 gold_assert(oldsym
!= NULL
);
1842 if (is_default_version
)
1844 Sized_symbol
<size
>* soldsym
=
1845 this->get_sized_symbol
<size
>(oldsym
);
1846 this->define_default_version
<size
, big_endian
>(soldsym
,
1853 // We haven't seen this symbol before.
1854 gold_assert(ins
.first
->second
== NULL
);
1856 add_to_table
= true;
1857 add_loc
= ins
.first
;
1859 if (is_default_version
&& !insdefault
.second
)
1861 // We are adding NAME/VERSION, and it is the default
1862 // version. We already have an entry for NAME/NULL.
1863 oldsym
= insdefault
.first
->second
;
1864 *resolve_oldsym
= true;
1870 if (is_default_version
)
1872 add_def_to_table
= true;
1873 add_def_loc
= insdefault
.first
;
1879 const Target
& target
= parameters
->target();
1880 if (!target
.has_make_symbol())
1881 sym
= new Sized_symbol
<size
>();
1884 Sized_target
<size
, big_endian
>* sized_target
=
1885 parameters
->sized_target
<size
, big_endian
>();
1886 sym
= sized_target
->make_symbol(*pname
, elfcpp::STT_NOTYPE
,
1887 NULL
, elfcpp::SHN_UNDEF
, 0);
1893 add_loc
->second
= sym
;
1895 gold_assert(oldsym
!= NULL
);
1897 if (add_def_to_table
)
1898 add_def_loc
->second
= sym
;
1900 *poldsym
= this->get_sized_symbol
<size
>(oldsym
);
1905 // Define a symbol based on an Output_data.
1908 Symbol_table::define_in_output_data(const char* name
,
1909 const char* version
,
1915 elfcpp::STB binding
,
1916 elfcpp::STV visibility
,
1917 unsigned char nonvis
,
1918 bool offset_is_from_end
,
1921 if (parameters
->target().get_size() == 32)
1923 #if defined(HAVE_TARGET_32_LITTLE) || defined(HAVE_TARGET_32_BIG)
1924 return this->do_define_in_output_data
<32>(name
, version
, defined
, od
,
1925 value
, symsize
, type
, binding
,
1933 else if (parameters
->target().get_size() == 64)
1935 #if defined(HAVE_TARGET_64_LITTLE) || defined(HAVE_TARGET_64_BIG)
1936 return this->do_define_in_output_data
<64>(name
, version
, defined
, od
,
1937 value
, symsize
, type
, binding
,
1949 // Define a symbol in an Output_data, sized version.
1953 Symbol_table::do_define_in_output_data(
1955 const char* version
,
1958 typename
elfcpp::Elf_types
<size
>::Elf_Addr value
,
1959 typename
elfcpp::Elf_types
<size
>::Elf_WXword symsize
,
1961 elfcpp::STB binding
,
1962 elfcpp::STV visibility
,
1963 unsigned char nonvis
,
1964 bool offset_is_from_end
,
1967 Sized_symbol
<size
>* sym
;
1968 Sized_symbol
<size
>* oldsym
;
1969 bool resolve_oldsym
;
1970 const bool is_forced_local
= binding
== elfcpp::STB_LOCAL
;
1972 if (parameters
->target().is_big_endian())
1974 #if defined(HAVE_TARGET_32_BIG) || defined(HAVE_TARGET_64_BIG)
1975 sym
= this->define_special_symbol
<size
, true>(&name
, &version
,
1976 only_if_ref
, &oldsym
,
1985 #if defined(HAVE_TARGET_32_LITTLE) || defined(HAVE_TARGET_64_LITTLE)
1986 sym
= this->define_special_symbol
<size
, false>(&name
, &version
,
1987 only_if_ref
, &oldsym
,
1998 sym
->init_output_data(name
, version
, od
, value
, symsize
, type
, binding
,
1999 visibility
, nonvis
, offset_is_from_end
,
2000 defined
== PREDEFINED
);
2004 if (is_forced_local
|| this->version_script_
.symbol_is_local(name
))
2005 this->force_local(sym
);
2006 else if (version
!= NULL
)
2007 sym
->set_is_default();
2011 if (Symbol_table::should_override_with_special(oldsym
, type
, defined
))
2012 this->override_with_special(oldsym
, sym
);
2018 if (defined
== PREDEFINED
2019 && (is_forced_local
|| this->version_script_
.symbol_is_local(name
)))
2020 this->force_local(oldsym
);
2026 // Define a symbol based on an Output_segment.
2029 Symbol_table::define_in_output_segment(const char* name
,
2030 const char* version
,
2036 elfcpp::STB binding
,
2037 elfcpp::STV visibility
,
2038 unsigned char nonvis
,
2039 Symbol::Segment_offset_base offset_base
,
2042 if (parameters
->target().get_size() == 32)
2044 #if defined(HAVE_TARGET_32_LITTLE) || defined(HAVE_TARGET_32_BIG)
2045 return this->do_define_in_output_segment
<32>(name
, version
, defined
, os
,
2046 value
, symsize
, type
,
2047 binding
, visibility
, nonvis
,
2048 offset_base
, only_if_ref
);
2053 else if (parameters
->target().get_size() == 64)
2055 #if defined(HAVE_TARGET_64_LITTLE) || defined(HAVE_TARGET_64_BIG)
2056 return this->do_define_in_output_segment
<64>(name
, version
, defined
, os
,
2057 value
, symsize
, type
,
2058 binding
, visibility
, nonvis
,
2059 offset_base
, only_if_ref
);
2068 // Define a symbol in an Output_segment, sized version.
2072 Symbol_table::do_define_in_output_segment(
2074 const char* version
,
2077 typename
elfcpp::Elf_types
<size
>::Elf_Addr value
,
2078 typename
elfcpp::Elf_types
<size
>::Elf_WXword symsize
,
2080 elfcpp::STB binding
,
2081 elfcpp::STV visibility
,
2082 unsigned char nonvis
,
2083 Symbol::Segment_offset_base offset_base
,
2086 Sized_symbol
<size
>* sym
;
2087 Sized_symbol
<size
>* oldsym
;
2088 bool resolve_oldsym
;
2089 const bool is_forced_local
= binding
== elfcpp::STB_LOCAL
;
2091 if (parameters
->target().is_big_endian())
2093 #if defined(HAVE_TARGET_32_BIG) || defined(HAVE_TARGET_64_BIG)
2094 sym
= this->define_special_symbol
<size
, true>(&name
, &version
,
2095 only_if_ref
, &oldsym
,
2104 #if defined(HAVE_TARGET_32_LITTLE) || defined(HAVE_TARGET_64_LITTLE)
2105 sym
= this->define_special_symbol
<size
, false>(&name
, &version
,
2106 only_if_ref
, &oldsym
,
2117 sym
->init_output_segment(name
, version
, os
, value
, symsize
, type
, binding
,
2118 visibility
, nonvis
, offset_base
,
2119 defined
== PREDEFINED
);
2123 if (is_forced_local
|| this->version_script_
.symbol_is_local(name
))
2124 this->force_local(sym
);
2125 else if (version
!= NULL
)
2126 sym
->set_is_default();
2130 if (Symbol_table::should_override_with_special(oldsym
, type
, defined
))
2131 this->override_with_special(oldsym
, sym
);
2137 if (is_forced_local
|| this->version_script_
.symbol_is_local(name
))
2138 this->force_local(oldsym
);
2144 // Define a special symbol with a constant value. It is a multiple
2145 // definition error if this symbol is already defined.
2148 Symbol_table::define_as_constant(const char* name
,
2149 const char* version
,
2154 elfcpp::STB binding
,
2155 elfcpp::STV visibility
,
2156 unsigned char nonvis
,
2158 bool force_override
)
2160 if (parameters
->target().get_size() == 32)
2162 #if defined(HAVE_TARGET_32_LITTLE) || defined(HAVE_TARGET_32_BIG)
2163 return this->do_define_as_constant
<32>(name
, version
, defined
, value
,
2164 symsize
, type
, binding
,
2165 visibility
, nonvis
, only_if_ref
,
2171 else if (parameters
->target().get_size() == 64)
2173 #if defined(HAVE_TARGET_64_LITTLE) || defined(HAVE_TARGET_64_BIG)
2174 return this->do_define_as_constant
<64>(name
, version
, defined
, value
,
2175 symsize
, type
, binding
,
2176 visibility
, nonvis
, only_if_ref
,
2186 // Define a symbol as a constant, sized version.
2190 Symbol_table::do_define_as_constant(
2192 const char* version
,
2194 typename
elfcpp::Elf_types
<size
>::Elf_Addr value
,
2195 typename
elfcpp::Elf_types
<size
>::Elf_WXword symsize
,
2197 elfcpp::STB binding
,
2198 elfcpp::STV visibility
,
2199 unsigned char nonvis
,
2201 bool force_override
)
2203 Sized_symbol
<size
>* sym
;
2204 Sized_symbol
<size
>* oldsym
;
2205 bool resolve_oldsym
;
2206 const bool is_forced_local
= binding
== elfcpp::STB_LOCAL
;
2208 if (parameters
->target().is_big_endian())
2210 #if defined(HAVE_TARGET_32_BIG) || defined(HAVE_TARGET_64_BIG)
2211 sym
= this->define_special_symbol
<size
, true>(&name
, &version
,
2212 only_if_ref
, &oldsym
,
2221 #if defined(HAVE_TARGET_32_LITTLE) || defined(HAVE_TARGET_64_LITTLE)
2222 sym
= this->define_special_symbol
<size
, false>(&name
, &version
,
2223 only_if_ref
, &oldsym
,
2234 sym
->init_constant(name
, version
, value
, symsize
, type
, binding
, visibility
,
2235 nonvis
, defined
== PREDEFINED
);
2239 // Version symbols are absolute symbols with name == version.
2240 // We don't want to force them to be local.
2241 if ((version
== NULL
2244 && (is_forced_local
|| this->version_script_
.symbol_is_local(name
)))
2245 this->force_local(sym
);
2246 else if (version
!= NULL
2247 && (name
!= version
|| value
!= 0))
2248 sym
->set_is_default();
2253 || Symbol_table::should_override_with_special(oldsym
, type
, defined
))
2254 this->override_with_special(oldsym
, sym
);
2260 if (is_forced_local
|| this->version_script_
.symbol_is_local(name
))
2261 this->force_local(oldsym
);
2267 // Define a set of symbols in output sections.
2270 Symbol_table::define_symbols(const Layout
* layout
, int count
,
2271 const Define_symbol_in_section
* p
,
2274 for (int i
= 0; i
< count
; ++i
, ++p
)
2276 Output_section
* os
= layout
->find_output_section(p
->output_section
);
2278 this->define_in_output_data(p
->name
, NULL
, PREDEFINED
, os
, p
->value
,
2279 p
->size
, p
->type
, p
->binding
,
2280 p
->visibility
, p
->nonvis
,
2281 p
->offset_is_from_end
,
2282 only_if_ref
|| p
->only_if_ref
);
2284 this->define_as_constant(p
->name
, NULL
, PREDEFINED
, 0, p
->size
,
2285 p
->type
, p
->binding
, p
->visibility
, p
->nonvis
,
2286 only_if_ref
|| p
->only_if_ref
,
2291 // Define a set of symbols in output segments.
2294 Symbol_table::define_symbols(const Layout
* layout
, int count
,
2295 const Define_symbol_in_segment
* p
,
2298 for (int i
= 0; i
< count
; ++i
, ++p
)
2300 Output_segment
* os
= layout
->find_output_segment(p
->segment_type
,
2301 p
->segment_flags_set
,
2302 p
->segment_flags_clear
);
2304 this->define_in_output_segment(p
->name
, NULL
, PREDEFINED
, os
, p
->value
,
2305 p
->size
, p
->type
, p
->binding
,
2306 p
->visibility
, p
->nonvis
,
2308 only_if_ref
|| p
->only_if_ref
);
2310 this->define_as_constant(p
->name
, NULL
, PREDEFINED
, 0, p
->size
,
2311 p
->type
, p
->binding
, p
->visibility
, p
->nonvis
,
2312 only_if_ref
|| p
->only_if_ref
,
2317 // Define CSYM using a COPY reloc. POSD is the Output_data where the
2318 // symbol should be defined--typically a .dyn.bss section. VALUE is
2319 // the offset within POSD.
2323 Symbol_table::define_with_copy_reloc(
2324 Sized_symbol
<size
>* csym
,
2326 typename
elfcpp::Elf_types
<size
>::Elf_Addr value
)
2328 gold_assert(csym
->is_from_dynobj());
2329 gold_assert(!csym
->is_copied_from_dynobj());
2330 Object
* object
= csym
->object();
2331 gold_assert(object
->is_dynamic());
2332 Dynobj
* dynobj
= static_cast<Dynobj
*>(object
);
2334 // Our copied variable has to override any variable in a shared
2336 elfcpp::STB binding
= csym
->binding();
2337 if (binding
== elfcpp::STB_WEAK
)
2338 binding
= elfcpp::STB_GLOBAL
;
2340 this->define_in_output_data(csym
->name(), csym
->version(), COPY
,
2341 posd
, value
, csym
->symsize(),
2342 csym
->type(), binding
,
2343 csym
->visibility(), csym
->nonvis(),
2346 csym
->set_is_copied_from_dynobj();
2347 csym
->set_needs_dynsym_entry();
2349 this->copied_symbol_dynobjs_
[csym
] = dynobj
;
2351 // We have now defined all aliases, but we have not entered them all
2352 // in the copied_symbol_dynobjs_ map.
2353 if (csym
->has_alias())
2358 sym
= this->weak_aliases_
[sym
];
2361 gold_assert(sym
->output_data() == posd
);
2363 sym
->set_is_copied_from_dynobj();
2364 this->copied_symbol_dynobjs_
[sym
] = dynobj
;
2369 // SYM is defined using a COPY reloc. Return the dynamic object where
2370 // the original definition was found.
2373 Symbol_table::get_copy_source(const Symbol
* sym
) const
2375 gold_assert(sym
->is_copied_from_dynobj());
2376 Copied_symbol_dynobjs::const_iterator p
=
2377 this->copied_symbol_dynobjs_
.find(sym
);
2378 gold_assert(p
!= this->copied_symbol_dynobjs_
.end());
2382 // Add any undefined symbols named on the command line.
2385 Symbol_table::add_undefined_symbols_from_command_line(Layout
* layout
)
2387 if (parameters
->options().any_undefined()
2388 || layout
->script_options()->any_unreferenced())
2390 if (parameters
->target().get_size() == 32)
2392 #if defined(HAVE_TARGET_32_LITTLE) || defined(HAVE_TARGET_32_BIG)
2393 this->do_add_undefined_symbols_from_command_line
<32>(layout
);
2398 else if (parameters
->target().get_size() == 64)
2400 #if defined(HAVE_TARGET_64_LITTLE) || defined(HAVE_TARGET_64_BIG)
2401 this->do_add_undefined_symbols_from_command_line
<64>(layout
);
2413 Symbol_table::do_add_undefined_symbols_from_command_line(Layout
* layout
)
2415 for (options::String_set::const_iterator p
=
2416 parameters
->options().undefined_begin();
2417 p
!= parameters
->options().undefined_end();
2419 this->add_undefined_symbol_from_command_line
<size
>(p
->c_str());
2421 for (options::String_set::const_iterator p
=
2422 parameters
->options().export_dynamic_symbol_begin();
2423 p
!= parameters
->options().export_dynamic_symbol_end();
2425 this->add_undefined_symbol_from_command_line
<size
>(p
->c_str());
2427 for (Script_options::referenced_const_iterator p
=
2428 layout
->script_options()->referenced_begin();
2429 p
!= layout
->script_options()->referenced_end();
2431 this->add_undefined_symbol_from_command_line
<size
>(p
->c_str());
2436 Symbol_table::add_undefined_symbol_from_command_line(const char* name
)
2438 if (this->lookup(name
) != NULL
)
2441 const char* version
= NULL
;
2443 Sized_symbol
<size
>* sym
;
2444 Sized_symbol
<size
>* oldsym
;
2445 bool resolve_oldsym
;
2446 if (parameters
->target().is_big_endian())
2448 #if defined(HAVE_TARGET_32_BIG) || defined(HAVE_TARGET_64_BIG)
2449 sym
= this->define_special_symbol
<size
, true>(&name
, &version
,
2459 #if defined(HAVE_TARGET_32_LITTLE) || defined(HAVE_TARGET_64_LITTLE)
2460 sym
= this->define_special_symbol
<size
, false>(&name
, &version
,
2469 gold_assert(oldsym
== NULL
);
2471 sym
->init_undefined(name
, version
, 0, elfcpp::STT_NOTYPE
, elfcpp::STB_GLOBAL
,
2472 elfcpp::STV_DEFAULT
, 0);
2473 ++this->saw_undefined_
;
2476 // Set the dynamic symbol indexes. INDEX is the index of the first
2477 // global dynamic symbol. Pointers to the global symbols are stored
2478 // into the vector SYMS. The names are added to DYNPOOL.
2479 // This returns an updated dynamic symbol index.
2482 Symbol_table::set_dynsym_indexes(unsigned int index
,
2483 unsigned int* pforced_local_count
,
2484 std::vector
<Symbol
*>* syms
,
2485 Stringpool
* dynpool
,
2488 std::vector
<Symbol
*> as_needed_sym
;
2490 // First process all the symbols which have been forced to be local,
2491 // as they must appear before all global symbols.
2492 unsigned int forced_local_count
= 0;
2493 for (Forced_locals::iterator p
= this->forced_locals_
.begin();
2494 p
!= this->forced_locals_
.end();
2498 gold_assert(sym
->is_forced_local());
2499 if (sym
->has_dynsym_index())
2501 if (!sym
->should_add_dynsym_entry(this))
2502 sym
->set_dynsym_index(-1U);
2505 sym
->set_dynsym_index(index
);
2507 ++forced_local_count
;
2508 dynpool
->add(sym
->name(), false, NULL
);
2511 *pforced_local_count
= forced_local_count
;
2513 // Allow a target to set dynsym indexes.
2514 if (parameters
->target().has_custom_set_dynsym_indexes())
2516 std::vector
<Symbol
*> dyn_symbols
;
2517 for (Symbol_table_type::iterator p
= this->table_
.begin();
2518 p
!= this->table_
.end();
2521 Symbol
* sym
= p
->second
;
2522 if (sym
->is_forced_local())
2524 if (!sym
->should_add_dynsym_entry(this))
2525 sym
->set_dynsym_index(-1U);
2527 dyn_symbols
.push_back(sym
);
2530 return parameters
->target().set_dynsym_indexes(&dyn_symbols
, index
, syms
,
2531 dynpool
, versions
, this);
2534 for (Symbol_table_type::iterator p
= this->table_
.begin();
2535 p
!= this->table_
.end();
2538 Symbol
* sym
= p
->second
;
2540 if (sym
->is_forced_local())
2543 // Note that SYM may already have a dynamic symbol index, since
2544 // some symbols appear more than once in the symbol table, with
2545 // and without a version.
2547 if (!sym
->should_add_dynsym_entry(this))
2548 sym
->set_dynsym_index(-1U);
2549 else if (!sym
->has_dynsym_index())
2551 sym
->set_dynsym_index(index
);
2553 syms
->push_back(sym
);
2554 dynpool
->add(sym
->name(), false, NULL
);
2556 // If the symbol is defined in a dynamic object and is
2557 // referenced strongly in a regular object, then mark the
2558 // dynamic object as needed. This is used to implement
2560 if (sym
->is_from_dynobj()
2562 && !sym
->is_undef_binding_weak())
2563 sym
->object()->set_is_needed();
2565 // Record any version information, except those from
2566 // as-needed libraries not seen to be needed. Note that the
2567 // is_needed state for such libraries can change in this loop.
2568 if (sym
->version() != NULL
)
2570 if (!sym
->is_from_dynobj()
2571 || !sym
->object()->as_needed()
2572 || sym
->object()->is_needed())
2573 versions
->record_version(this, dynpool
, sym
);
2575 as_needed_sym
.push_back(sym
);
2580 // Process version information for symbols from as-needed libraries.
2581 for (std::vector
<Symbol
*>::iterator p
= as_needed_sym
.begin();
2582 p
!= as_needed_sym
.end();
2587 if (sym
->object()->is_needed())
2588 versions
->record_version(this, dynpool
, sym
);
2590 sym
->clear_version();
2593 // Finish up the versions. In some cases this may add new dynamic
2595 index
= versions
->finalize(this, index
, syms
);
2597 // Process target-specific symbols.
2598 for (std::vector
<Symbol
*>::iterator p
= this->target_symbols_
.begin();
2599 p
!= this->target_symbols_
.end();
2602 (*p
)->set_dynsym_index(index
);
2604 syms
->push_back(*p
);
2605 dynpool
->add((*p
)->name(), false, NULL
);
2611 // Set the final values for all the symbols. The index of the first
2612 // global symbol in the output file is *PLOCAL_SYMCOUNT. Record the
2613 // file offset OFF. Add their names to POOL. Return the new file
2614 // offset. Update *PLOCAL_SYMCOUNT if necessary. DYNOFF and
2615 // DYN_GLOBAL_INDEX refer to the start of the symbols that will be
2616 // written from the global symbol table in Symtab::write_globals(),
2617 // which will include forced-local symbols. DYN_GLOBAL_INDEX is
2618 // not necessarily the same as the sh_info field for the .dynsym
2619 // section, which will point to the first real global symbol.
2622 Symbol_table::finalize(off_t off
, off_t dynoff
, size_t dyn_global_index
,
2623 size_t dyncount
, Stringpool
* pool
,
2624 unsigned int* plocal_symcount
)
2628 gold_assert(*plocal_symcount
!= 0);
2629 this->first_global_index_
= *plocal_symcount
;
2631 this->dynamic_offset_
= dynoff
;
2632 this->first_dynamic_global_index_
= dyn_global_index
;
2633 this->dynamic_count_
= dyncount
;
2635 if (parameters
->target().get_size() == 32)
2637 #if defined(HAVE_TARGET_32_BIG) || defined(HAVE_TARGET_32_LITTLE)
2638 ret
= this->sized_finalize
<32>(off
, pool
, plocal_symcount
);
2643 else if (parameters
->target().get_size() == 64)
2645 #if defined(HAVE_TARGET_64_BIG) || defined(HAVE_TARGET_64_LITTLE)
2646 ret
= this->sized_finalize
<64>(off
, pool
, plocal_symcount
);
2654 // Now that we have the final symbol table, we can reliably note
2655 // which symbols should get warnings.
2656 this->warnings_
.note_warnings(this);
2661 // SYM is going into the symbol table at *PINDEX. Add the name to
2662 // POOL, update *PINDEX and *POFF.
2666 Symbol_table::add_to_final_symtab(Symbol
* sym
, Stringpool
* pool
,
2667 unsigned int* pindex
, off_t
* poff
)
2669 sym
->set_symtab_index(*pindex
);
2670 if (sym
->version() == NULL
|| !parameters
->options().relocatable())
2671 pool
->add(sym
->name(), false, NULL
);
2673 pool
->add(sym
->versioned_name(), true, NULL
);
2675 *poff
+= elfcpp::Elf_sizes
<size
>::sym_size
;
2678 // Set the final value for all the symbols. This is called after
2679 // Layout::finalize, so all the output sections have their final
2684 Symbol_table::sized_finalize(off_t off
, Stringpool
* pool
,
2685 unsigned int* plocal_symcount
)
2687 off
= align_address(off
, size
>> 3);
2688 this->offset_
= off
;
2690 unsigned int index
= *plocal_symcount
;
2691 const unsigned int orig_index
= index
;
2693 // First do all the symbols which have been forced to be local, as
2694 // they must appear before all global symbols.
2695 for (Forced_locals::iterator p
= this->forced_locals_
.begin();
2696 p
!= this->forced_locals_
.end();
2700 gold_assert(sym
->is_forced_local());
2701 if (this->sized_finalize_symbol
<size
>(sym
))
2703 this->add_to_final_symtab
<size
>(sym
, pool
, &index
, &off
);
2708 // Now do all the remaining symbols.
2709 for (Symbol_table_type::iterator p
= this->table_
.begin();
2710 p
!= this->table_
.end();
2713 Symbol
* sym
= p
->second
;
2714 if (this->sized_finalize_symbol
<size
>(sym
))
2715 this->add_to_final_symtab
<size
>(sym
, pool
, &index
, &off
);
2718 // Now do target-specific symbols.
2719 for (std::vector
<Symbol
*>::iterator p
= this->target_symbols_
.begin();
2720 p
!= this->target_symbols_
.end();
2723 this->add_to_final_symtab
<size
>(*p
, pool
, &index
, &off
);
2726 this->output_count_
= index
- orig_index
;
2731 // Compute the final value of SYM and store status in location PSTATUS.
2732 // During relaxation, this may be called multiple times for a symbol to
2733 // compute its would-be final value in each relaxation pass.
2736 typename Sized_symbol
<size
>::Value_type
2737 Symbol_table::compute_final_value(
2738 const Sized_symbol
<size
>* sym
,
2739 Compute_final_value_status
* pstatus
) const
2741 typedef typename Sized_symbol
<size
>::Value_type Value_type
;
2744 switch (sym
->source())
2746 case Symbol::FROM_OBJECT
:
2749 unsigned int shndx
= sym
->shndx(&is_ordinary
);
2752 && shndx
!= elfcpp::SHN_ABS
2753 && !Symbol::is_common_shndx(shndx
))
2755 *pstatus
= CFVS_UNSUPPORTED_SYMBOL_SECTION
;
2759 Object
* symobj
= sym
->object();
2760 if (symobj
->is_dynamic())
2763 shndx
= elfcpp::SHN_UNDEF
;
2765 else if (symobj
->pluginobj() != NULL
)
2768 shndx
= elfcpp::SHN_UNDEF
;
2770 else if (shndx
== elfcpp::SHN_UNDEF
)
2772 else if (!is_ordinary
2773 && (shndx
== elfcpp::SHN_ABS
2774 || Symbol::is_common_shndx(shndx
)))
2775 value
= sym
->value();
2778 Relobj
* relobj
= static_cast<Relobj
*>(symobj
);
2779 Output_section
* os
= relobj
->output_section(shndx
);
2781 if (this->is_section_folded(relobj
, shndx
))
2783 gold_assert(os
== NULL
);
2784 // Get the os of the section it is folded onto.
2785 Section_id folded
= this->icf_
->get_folded_section(relobj
,
2787 gold_assert(folded
.first
!= NULL
);
2788 Relobj
* folded_obj
= reinterpret_cast<Relobj
*>(folded
.first
);
2789 unsigned folded_shndx
= folded
.second
;
2791 os
= folded_obj
->output_section(folded_shndx
);
2792 gold_assert(os
!= NULL
);
2794 // Replace (relobj, shndx) with canonical ICF input section.
2795 shndx
= folded_shndx
;
2796 relobj
= folded_obj
;
2799 uint64_t secoff64
= relobj
->output_section_offset(shndx
);
2802 bool static_or_reloc
= (parameters
->doing_static_link() ||
2803 parameters
->options().relocatable());
2804 gold_assert(static_or_reloc
|| sym
->dynsym_index() == -1U);
2806 *pstatus
= CFVS_NO_OUTPUT_SECTION
;
2810 if (secoff64
== -1ULL)
2812 // The section needs special handling (e.g., a merge section).
2814 value
= os
->output_address(relobj
, shndx
, sym
->value());
2819 convert_types
<Value_type
, uint64_t>(secoff64
);
2820 if (sym
->type() == elfcpp::STT_TLS
)
2821 value
= sym
->value() + os
->tls_offset() + secoff
;
2823 value
= sym
->value() + os
->address() + secoff
;
2829 case Symbol::IN_OUTPUT_DATA
:
2831 Output_data
* od
= sym
->output_data();
2832 value
= sym
->value();
2833 if (sym
->type() != elfcpp::STT_TLS
)
2834 value
+= od
->address();
2837 Output_section
* os
= od
->output_section();
2838 gold_assert(os
!= NULL
);
2839 value
+= os
->tls_offset() + (od
->address() - os
->address());
2841 if (sym
->offset_is_from_end())
2842 value
+= od
->data_size();
2846 case Symbol::IN_OUTPUT_SEGMENT
:
2848 Output_segment
* os
= sym
->output_segment();
2849 value
= sym
->value();
2850 if (sym
->type() != elfcpp::STT_TLS
)
2851 value
+= os
->vaddr();
2852 switch (sym
->offset_base())
2854 case Symbol::SEGMENT_START
:
2856 case Symbol::SEGMENT_END
:
2857 value
+= os
->memsz();
2859 case Symbol::SEGMENT_BSS
:
2860 value
+= os
->filesz();
2868 case Symbol::IS_CONSTANT
:
2869 value
= sym
->value();
2872 case Symbol::IS_UNDEFINED
:
2884 // Finalize the symbol SYM. This returns true if the symbol should be
2885 // added to the symbol table, false otherwise.
2889 Symbol_table::sized_finalize_symbol(Symbol
* unsized_sym
)
2891 typedef typename Sized_symbol
<size
>::Value_type Value_type
;
2893 Sized_symbol
<size
>* sym
= static_cast<Sized_symbol
<size
>*>(unsized_sym
);
2895 // The default version of a symbol may appear twice in the symbol
2896 // table. We only need to finalize it once.
2897 if (sym
->has_symtab_index())
2902 gold_assert(!sym
->has_symtab_index());
2903 sym
->set_symtab_index(-1U);
2904 gold_assert(sym
->dynsym_index() == -1U);
2908 // If the symbol is only present on plugin files, the plugin decided we
2910 if (!sym
->in_real_elf())
2912 gold_assert(!sym
->has_symtab_index());
2913 sym
->set_symtab_index(-1U);
2917 // Compute final symbol value.
2918 Compute_final_value_status status
;
2919 Value_type value
= this->compute_final_value(sym
, &status
);
2925 case CFVS_UNSUPPORTED_SYMBOL_SECTION
:
2928 unsigned int shndx
= sym
->shndx(&is_ordinary
);
2929 gold_error(_("%s: unsupported symbol section 0x%x"),
2930 sym
->demangled_name().c_str(), shndx
);
2933 case CFVS_NO_OUTPUT_SECTION
:
2934 sym
->set_symtab_index(-1U);
2940 sym
->set_value(value
);
2942 if (parameters
->options().strip_all()
2943 || !parameters
->options().should_retain_symbol(sym
->name()))
2945 sym
->set_symtab_index(-1U);
2952 // Write out the global symbols.
2955 Symbol_table::write_globals(const Stringpool
* sympool
,
2956 const Stringpool
* dynpool
,
2957 Output_symtab_xindex
* symtab_xindex
,
2958 Output_symtab_xindex
* dynsym_xindex
,
2959 Output_file
* of
) const
2961 switch (parameters
->size_and_endianness())
2963 #ifdef HAVE_TARGET_32_LITTLE
2964 case Parameters::TARGET_32_LITTLE
:
2965 this->sized_write_globals
<32, false>(sympool
, dynpool
, symtab_xindex
,
2969 #ifdef HAVE_TARGET_32_BIG
2970 case Parameters::TARGET_32_BIG
:
2971 this->sized_write_globals
<32, true>(sympool
, dynpool
, symtab_xindex
,
2975 #ifdef HAVE_TARGET_64_LITTLE
2976 case Parameters::TARGET_64_LITTLE
:
2977 this->sized_write_globals
<64, false>(sympool
, dynpool
, symtab_xindex
,
2981 #ifdef HAVE_TARGET_64_BIG
2982 case Parameters::TARGET_64_BIG
:
2983 this->sized_write_globals
<64, true>(sympool
, dynpool
, symtab_xindex
,
2992 // Write out the global symbols.
2994 template<int size
, bool big_endian
>
2996 Symbol_table::sized_write_globals(const Stringpool
* sympool
,
2997 const Stringpool
* dynpool
,
2998 Output_symtab_xindex
* symtab_xindex
,
2999 Output_symtab_xindex
* dynsym_xindex
,
3000 Output_file
* of
) const
3002 const Target
& target
= parameters
->target();
3004 const int sym_size
= elfcpp::Elf_sizes
<size
>::sym_size
;
3006 const unsigned int output_count
= this->output_count_
;
3007 const section_size_type oview_size
= output_count
* sym_size
;
3008 const unsigned int first_global_index
= this->first_global_index_
;
3009 unsigned char* psyms
;
3010 if (this->offset_
== 0 || output_count
== 0)
3013 psyms
= of
->get_output_view(this->offset_
, oview_size
);
3015 const unsigned int dynamic_count
= this->dynamic_count_
;
3016 const section_size_type dynamic_size
= dynamic_count
* sym_size
;
3017 const unsigned int first_dynamic_global_index
=
3018 this->first_dynamic_global_index_
;
3019 unsigned char* dynamic_view
;
3020 if (this->dynamic_offset_
== 0 || dynamic_count
== 0)
3021 dynamic_view
= NULL
;
3023 dynamic_view
= of
->get_output_view(this->dynamic_offset_
, dynamic_size
);
3025 for (Symbol_table_type::const_iterator p
= this->table_
.begin();
3026 p
!= this->table_
.end();
3029 Sized_symbol
<size
>* sym
= static_cast<Sized_symbol
<size
>*>(p
->second
);
3031 // Possibly warn about unresolved symbols in shared libraries.
3032 this->warn_about_undefined_dynobj_symbol(sym
);
3034 unsigned int sym_index
= sym
->symtab_index();
3035 unsigned int dynsym_index
;
3036 if (dynamic_view
== NULL
)
3039 dynsym_index
= sym
->dynsym_index();
3041 if (sym_index
== -1U && dynsym_index
== -1U)
3043 // This symbol is not included in the output file.
3048 typename
elfcpp::Elf_types
<size
>::Elf_Addr sym_value
= sym
->value();
3049 typename
elfcpp::Elf_types
<size
>::Elf_Addr dynsym_value
= sym_value
;
3050 elfcpp::STB binding
= sym
->binding();
3052 // If --weak-unresolved-symbols is set, change binding of unresolved
3053 // global symbols to STB_WEAK.
3054 if (parameters
->options().weak_unresolved_symbols()
3055 && binding
== elfcpp::STB_GLOBAL
3056 && sym
->is_undefined())
3057 binding
= elfcpp::STB_WEAK
;
3059 // If --no-gnu-unique is set, change STB_GNU_UNIQUE to STB_GLOBAL.
3060 if (binding
== elfcpp::STB_GNU_UNIQUE
3061 && !parameters
->options().gnu_unique())
3062 binding
= elfcpp::STB_GLOBAL
;
3064 switch (sym
->source())
3066 case Symbol::FROM_OBJECT
:
3069 unsigned int in_shndx
= sym
->shndx(&is_ordinary
);
3072 && in_shndx
!= elfcpp::SHN_ABS
3073 && !Symbol::is_common_shndx(in_shndx
))
3075 gold_error(_("%s: unsupported symbol section 0x%x"),
3076 sym
->demangled_name().c_str(), in_shndx
);
3081 Object
* symobj
= sym
->object();
3082 if (symobj
->is_dynamic())
3084 if (sym
->needs_dynsym_value())
3085 dynsym_value
= target
.dynsym_value(sym
);
3086 shndx
= elfcpp::SHN_UNDEF
;
3087 if (sym
->is_undef_binding_weak())
3088 binding
= elfcpp::STB_WEAK
;
3090 binding
= elfcpp::STB_GLOBAL
;
3092 else if (symobj
->pluginobj() != NULL
)
3093 shndx
= elfcpp::SHN_UNDEF
;
3094 else if (in_shndx
== elfcpp::SHN_UNDEF
3096 && (in_shndx
== elfcpp::SHN_ABS
3097 || Symbol::is_common_shndx(in_shndx
))))
3101 Relobj
* relobj
= static_cast<Relobj
*>(symobj
);
3102 Output_section
* os
= relobj
->output_section(in_shndx
);
3103 if (this->is_section_folded(relobj
, in_shndx
))
3105 // This global symbol must be written out even though
3107 // Get the os of the section it is folded onto.
3109 this->icf_
->get_folded_section(relobj
, in_shndx
);
3110 gold_assert(folded
.first
!=NULL
);
3111 Relobj
* folded_obj
=
3112 reinterpret_cast<Relobj
*>(folded
.first
);
3113 os
= folded_obj
->output_section(folded
.second
);
3114 gold_assert(os
!= NULL
);
3116 gold_assert(os
!= NULL
);
3117 shndx
= os
->out_shndx();
3119 if (shndx
>= elfcpp::SHN_LORESERVE
)
3121 if (sym_index
!= -1U)
3122 symtab_xindex
->add(sym_index
, shndx
);
3123 if (dynsym_index
!= -1U)
3124 dynsym_xindex
->add(dynsym_index
, shndx
);
3125 shndx
= elfcpp::SHN_XINDEX
;
3128 // In object files symbol values are section
3130 if (parameters
->options().relocatable())
3131 sym_value
-= os
->address();
3137 case Symbol::IN_OUTPUT_DATA
:
3139 Output_data
* od
= sym
->output_data();
3141 shndx
= od
->out_shndx();
3142 if (shndx
>= elfcpp::SHN_LORESERVE
)
3144 if (sym_index
!= -1U)
3145 symtab_xindex
->add(sym_index
, shndx
);
3146 if (dynsym_index
!= -1U)
3147 dynsym_xindex
->add(dynsym_index
, shndx
);
3148 shndx
= elfcpp::SHN_XINDEX
;
3151 // In object files symbol values are section
3153 if (parameters
->options().relocatable())
3155 Output_section
* os
= od
->output_section();
3156 gold_assert(os
!= NULL
);
3157 sym_value
-= os
->address();
3162 case Symbol::IN_OUTPUT_SEGMENT
:
3164 Output_segment
* oseg
= sym
->output_segment();
3165 Output_section
* osect
= oseg
->first_section();
3167 shndx
= elfcpp::SHN_ABS
;
3169 shndx
= osect
->out_shndx();
3173 case Symbol::IS_CONSTANT
:
3174 shndx
= elfcpp::SHN_ABS
;
3177 case Symbol::IS_UNDEFINED
:
3178 shndx
= elfcpp::SHN_UNDEF
;
3185 if (sym_index
!= -1U)
3187 sym_index
-= first_global_index
;
3188 gold_assert(sym_index
< output_count
);
3189 unsigned char* ps
= psyms
+ (sym_index
* sym_size
);
3190 this->sized_write_symbol
<size
, big_endian
>(sym
, sym_value
, shndx
,
3191 binding
, sympool
, ps
);
3194 if (dynsym_index
!= -1U)
3196 dynsym_index
-= first_dynamic_global_index
;
3197 gold_assert(dynsym_index
< dynamic_count
);
3198 unsigned char* pd
= dynamic_view
+ (dynsym_index
* sym_size
);
3199 this->sized_write_symbol
<size
, big_endian
>(sym
, dynsym_value
, shndx
,
3200 binding
, dynpool
, pd
);
3201 // Allow a target to adjust dynamic symbol value.
3202 parameters
->target().adjust_dyn_symbol(sym
, pd
);
3206 // Write the target-specific symbols.
3207 for (std::vector
<Symbol
*>::const_iterator p
= this->target_symbols_
.begin();
3208 p
!= this->target_symbols_
.end();
3211 Sized_symbol
<size
>* sym
= static_cast<Sized_symbol
<size
>*>(*p
);
3213 unsigned int sym_index
= sym
->symtab_index();
3214 unsigned int dynsym_index
;
3215 if (dynamic_view
== NULL
)
3218 dynsym_index
= sym
->dynsym_index();
3221 switch (sym
->source())
3223 case Symbol::IS_CONSTANT
:
3224 shndx
= elfcpp::SHN_ABS
;
3226 case Symbol::IS_UNDEFINED
:
3227 shndx
= elfcpp::SHN_UNDEF
;
3233 if (sym_index
!= -1U)
3235 sym_index
-= first_global_index
;
3236 gold_assert(sym_index
< output_count
);
3237 unsigned char* ps
= psyms
+ (sym_index
* sym_size
);
3238 this->sized_write_symbol
<size
, big_endian
>(sym
, sym
->value(), shndx
,
3239 sym
->binding(), sympool
,
3243 if (dynsym_index
!= -1U)
3245 dynsym_index
-= first_dynamic_global_index
;
3246 gold_assert(dynsym_index
< dynamic_count
);
3247 unsigned char* pd
= dynamic_view
+ (dynsym_index
* sym_size
);
3248 this->sized_write_symbol
<size
, big_endian
>(sym
, sym
->value(), shndx
,
3249 sym
->binding(), dynpool
,
3254 of
->write_output_view(this->offset_
, oview_size
, psyms
);
3255 if (dynamic_view
!= NULL
)
3256 of
->write_output_view(this->dynamic_offset_
, dynamic_size
, dynamic_view
);
3259 // Write out the symbol SYM, in section SHNDX, to P. POOL is the
3260 // strtab holding the name.
3262 template<int size
, bool big_endian
>
3264 Symbol_table::sized_write_symbol(
3265 Sized_symbol
<size
>* sym
,
3266 typename
elfcpp::Elf_types
<size
>::Elf_Addr value
,
3268 elfcpp::STB binding
,
3269 const Stringpool
* pool
,
3270 unsigned char* p
) const
3272 elfcpp::Sym_write
<size
, big_endian
> osym(p
);
3273 if (sym
->version() == NULL
|| !parameters
->options().relocatable())
3274 osym
.put_st_name(pool
->get_offset(sym
->name()));
3276 osym
.put_st_name(pool
->get_offset(sym
->versioned_name()));
3277 osym
.put_st_value(value
);
3278 // Use a symbol size of zero for undefined symbols from shared libraries.
3279 if (shndx
== elfcpp::SHN_UNDEF
&& sym
->is_from_dynobj())
3280 osym
.put_st_size(0);
3282 osym
.put_st_size(sym
->symsize());
3283 elfcpp::STT type
= sym
->type();
3284 gold_assert(type
!= elfcpp::STT_GNU_IFUNC
|| !sym
->is_from_dynobj());
3285 // A version script may have overridden the default binding.
3286 if (sym
->is_forced_local())
3287 osym
.put_st_info(elfcpp::elf_st_info(elfcpp::STB_LOCAL
, type
));
3289 osym
.put_st_info(elfcpp::elf_st_info(binding
, type
));
3290 osym
.put_st_other(elfcpp::elf_st_other(sym
->visibility(), sym
->nonvis()));
3291 osym
.put_st_shndx(shndx
);
3294 // Check for unresolved symbols in shared libraries. This is
3295 // controlled by the --allow-shlib-undefined option.
3297 // We only warn about libraries for which we have seen all the
3298 // DT_NEEDED entries. We don't try to track down DT_NEEDED entries
3299 // which were not seen in this link. If we didn't see a DT_NEEDED
3300 // entry, we aren't going to be able to reliably report whether the
3301 // symbol is undefined.
3303 // We also don't warn about libraries found in a system library
3304 // directory (e.g., /lib or /usr/lib); we assume that those libraries
3305 // are OK. This heuristic avoids problems on GNU/Linux, in which -ldl
3306 // can have undefined references satisfied by ld-linux.so.
3309 Symbol_table::warn_about_undefined_dynobj_symbol(Symbol
* sym
) const
3312 if (sym
->source() == Symbol::FROM_OBJECT
3313 && sym
->object()->is_dynamic()
3314 && sym
->shndx(&dummy
) == elfcpp::SHN_UNDEF
3315 && sym
->binding() != elfcpp::STB_WEAK
3316 && !parameters
->options().allow_shlib_undefined()
3317 && !parameters
->target().is_defined_by_abi(sym
)
3318 && !sym
->object()->is_in_system_directory())
3320 // A very ugly cast.
3321 Dynobj
* dynobj
= static_cast<Dynobj
*>(sym
->object());
3322 if (!dynobj
->has_unknown_needed_entries())
3323 gold_undefined_symbol(sym
);
3327 // Write out a section symbol. Return the update offset.
3330 Symbol_table::write_section_symbol(const Output_section
* os
,
3331 Output_symtab_xindex
* symtab_xindex
,
3335 switch (parameters
->size_and_endianness())
3337 #ifdef HAVE_TARGET_32_LITTLE
3338 case Parameters::TARGET_32_LITTLE
:
3339 this->sized_write_section_symbol
<32, false>(os
, symtab_xindex
, of
,
3343 #ifdef HAVE_TARGET_32_BIG
3344 case Parameters::TARGET_32_BIG
:
3345 this->sized_write_section_symbol
<32, true>(os
, symtab_xindex
, of
,
3349 #ifdef HAVE_TARGET_64_LITTLE
3350 case Parameters::TARGET_64_LITTLE
:
3351 this->sized_write_section_symbol
<64, false>(os
, symtab_xindex
, of
,
3355 #ifdef HAVE_TARGET_64_BIG
3356 case Parameters::TARGET_64_BIG
:
3357 this->sized_write_section_symbol
<64, true>(os
, symtab_xindex
, of
,
3366 // Write out a section symbol, specialized for size and endianness.
3368 template<int size
, bool big_endian
>
3370 Symbol_table::sized_write_section_symbol(const Output_section
* os
,
3371 Output_symtab_xindex
* symtab_xindex
,
3375 const int sym_size
= elfcpp::Elf_sizes
<size
>::sym_size
;
3377 unsigned char* pov
= of
->get_output_view(offset
, sym_size
);
3379 elfcpp::Sym_write
<size
, big_endian
> osym(pov
);
3380 osym
.put_st_name(0);
3381 if (parameters
->options().relocatable())
3382 osym
.put_st_value(0);
3384 osym
.put_st_value(os
->address());
3385 osym
.put_st_size(0);
3386 osym
.put_st_info(elfcpp::elf_st_info(elfcpp::STB_LOCAL
,
3387 elfcpp::STT_SECTION
));
3388 osym
.put_st_other(elfcpp::elf_st_other(elfcpp::STV_DEFAULT
, 0));
3390 unsigned int shndx
= os
->out_shndx();
3391 if (shndx
>= elfcpp::SHN_LORESERVE
)
3393 symtab_xindex
->add(os
->symtab_index(), shndx
);
3394 shndx
= elfcpp::SHN_XINDEX
;
3396 osym
.put_st_shndx(shndx
);
3398 of
->write_output_view(offset
, sym_size
, pov
);
3401 // Print statistical information to stderr. This is used for --stats.
3404 Symbol_table::print_stats() const
3406 #if defined(HAVE_TR1_UNORDERED_MAP) || defined(HAVE_EXT_HASH_MAP)
3407 fprintf(stderr
, _("%s: symbol table entries: %zu; buckets: %zu\n"),
3408 program_name
, this->table_
.size(), this->table_
.bucket_count());
3410 fprintf(stderr
, _("%s: symbol table entries: %zu\n"),
3411 program_name
, this->table_
.size());
3413 this->namepool_
.print_stats("symbol table stringpool");
3416 // We check for ODR violations by looking for symbols with the same
3417 // name for which the debugging information reports that they were
3418 // defined in disjoint source locations. When comparing the source
3419 // location, we consider instances with the same base filename to be
3420 // the same. This is because different object files/shared libraries
3421 // can include the same header file using different paths, and
3422 // different optimization settings can make the line number appear to
3423 // be a couple lines off, and we don't want to report an ODR violation
3426 // This struct is used to compare line information, as returned by
3427 // Dwarf_line_info::one_addr2line. It implements a < comparison
3428 // operator used with std::sort.
3430 struct Odr_violation_compare
3433 operator()(const std::string
& s1
, const std::string
& s2
) const
3435 // Inputs should be of the form "dirname/filename:linenum" where
3436 // "dirname/" is optional. We want to compare just the filename:linenum.
3438 // Find the last '/' in each string.
3439 std::string::size_type s1begin
= s1
.rfind('/');
3440 std::string::size_type s2begin
= s2
.rfind('/');
3441 // If there was no '/' in a string, start at the beginning.
3442 if (s1begin
== std::string::npos
)
3444 if (s2begin
== std::string::npos
)
3446 return s1
.compare(s1begin
, std::string::npos
,
3447 s2
, s2begin
, std::string::npos
) < 0;
3451 // Returns all of the lines attached to LOC, not just the one the
3452 // instruction actually came from.
3453 std::vector
<std::string
>
3454 Symbol_table::linenos_from_loc(const Task
* task
,
3455 const Symbol_location
& loc
)
3457 // We need to lock the object in order to read it. This
3458 // means that we have to run in a singleton Task. If we
3459 // want to run this in a general Task for better
3460 // performance, we will need one Task for object, plus
3461 // appropriate locking to ensure that we don't conflict with
3462 // other uses of the object. Also note, one_addr2line is not
3463 // currently thread-safe.
3464 Task_lock_obj
<Object
> tl(task
, loc
.object
);
3466 std::vector
<std::string
> result
;
3467 Symbol_location code_loc
= loc
;
3468 parameters
->target().function_location(&code_loc
);
3469 // 16 is the size of the object-cache that one_addr2line should use.
3470 std::string canonical_result
= Dwarf_line_info::one_addr2line(
3471 code_loc
.object
, code_loc
.shndx
, code_loc
.offset
, 16, &result
);
3472 if (!canonical_result
.empty())
3473 result
.push_back(canonical_result
);
3477 // OutputIterator that records if it was ever assigned to. This
3478 // allows it to be used with std::set_intersection() to check for
3479 // intersection rather than computing the intersection.
3480 struct Check_intersection
3482 Check_intersection()
3486 bool had_intersection() const
3487 { return this->value_
; }
3489 Check_intersection
& operator++()
3492 Check_intersection
& operator*()
3495 template<typename T
>
3496 Check_intersection
& operator=(const T
&)
3498 this->value_
= true;
3506 // Check candidate_odr_violations_ to find symbols with the same name
3507 // but apparently different definitions (different source-file/line-no
3508 // for each line assigned to the first instruction).
3511 Symbol_table::detect_odr_violations(const Task
* task
,
3512 const char* output_file_name
) const
3514 for (Odr_map::const_iterator it
= candidate_odr_violations_
.begin();
3515 it
!= candidate_odr_violations_
.end();
3518 const char* const symbol_name
= it
->first
;
3520 std::string first_object_name
;
3521 std::vector
<std::string
> first_object_linenos
;
3523 Unordered_set
<Symbol_location
, Symbol_location_hash
>::const_iterator
3524 locs
= it
->second
.begin();
3525 const Unordered_set
<Symbol_location
, Symbol_location_hash
>::const_iterator
3526 locs_end
= it
->second
.end();
3527 for (; locs
!= locs_end
&& first_object_linenos
.empty(); ++locs
)
3529 // Save the line numbers from the first definition to
3530 // compare to the other definitions. Ideally, we'd compare
3531 // every definition to every other, but we don't want to
3532 // take O(N^2) time to do this. This shortcut may cause
3533 // false negatives that appear or disappear depending on the
3534 // link order, but it won't cause false positives.
3535 first_object_name
= locs
->object
->name();
3536 first_object_linenos
= this->linenos_from_loc(task
, *locs
);
3538 if (first_object_linenos
.empty())
3541 // Sort by Odr_violation_compare to make std::set_intersection work.
3542 std::string first_object_canonical_result
= first_object_linenos
.back();
3543 std::sort(first_object_linenos
.begin(), first_object_linenos
.end(),
3544 Odr_violation_compare());
3546 for (; locs
!= locs_end
; ++locs
)
3548 std::vector
<std::string
> linenos
=
3549 this->linenos_from_loc(task
, *locs
);
3550 // linenos will be empty if we couldn't parse the debug info.
3551 if (linenos
.empty())
3553 // Sort by Odr_violation_compare to make std::set_intersection work.
3554 gold_assert(!linenos
.empty());
3555 std::string second_object_canonical_result
= linenos
.back();
3556 std::sort(linenos
.begin(), linenos
.end(), Odr_violation_compare());
3558 Check_intersection intersection_result
=
3559 std::set_intersection(first_object_linenos
.begin(),
3560 first_object_linenos
.end(),
3563 Check_intersection(),
3564 Odr_violation_compare());
3565 if (!intersection_result
.had_intersection())
3567 gold_warning(_("while linking %s: symbol '%s' defined in "
3568 "multiple places (possible ODR violation):"),
3569 output_file_name
, demangle(symbol_name
).c_str());
3570 // This only prints one location from each definition,
3571 // which may not be the location we expect to intersect
3572 // with another definition. We could print the whole
3573 // set of locations, but that seems too verbose.
3574 fprintf(stderr
, _(" %s from %s\n"),
3575 first_object_canonical_result
.c_str(),
3576 first_object_name
.c_str());
3577 fprintf(stderr
, _(" %s from %s\n"),
3578 second_object_canonical_result
.c_str(),
3579 locs
->object
->name().c_str());
3580 // Only print one broken pair, to avoid needing to
3581 // compare against a list of the disjoint definition
3582 // locations we've found so far. (If we kept comparing
3583 // against just the first one, we'd get a lot of
3584 // redundant complaints about the second definition
3590 // We only call one_addr2line() in this function, so we can clear its cache.
3591 Dwarf_line_info::clear_addr2line_cache();
3594 // Warnings functions.
3596 // Add a new warning.
3599 Warnings::add_warning(Symbol_table
* symtab
, const char* name
, Object
* obj
,
3600 const std::string
& warning
)
3602 name
= symtab
->canonicalize_name(name
);
3603 this->warnings_
[name
].set(obj
, warning
);
3606 // Look through the warnings and mark the symbols for which we should
3607 // warn. This is called during Layout::finalize when we know the
3608 // sources for all the symbols.
3611 Warnings::note_warnings(Symbol_table
* symtab
)
3613 for (Warning_table::iterator p
= this->warnings_
.begin();
3614 p
!= this->warnings_
.end();
3617 Symbol
* sym
= symtab
->lookup(p
->first
, NULL
);
3619 && sym
->source() == Symbol::FROM_OBJECT
3620 && sym
->object() == p
->second
.object
)
3621 sym
->set_has_warning();
3625 // Issue a warning. This is called when we see a relocation against a
3626 // symbol for which has a warning.
3628 template<int size
, bool big_endian
>
3630 Warnings::issue_warning(const Symbol
* sym
,
3631 const Relocate_info
<size
, big_endian
>* relinfo
,
3632 size_t relnum
, off_t reloffset
) const
3634 gold_assert(sym
->has_warning());
3636 // We don't want to issue a warning for a relocation against the
3637 // symbol in the same object file in which the symbol is defined.
3638 if (sym
->object() == relinfo
->object
)
3641 Warning_table::const_iterator p
= this->warnings_
.find(sym
->name());
3642 gold_assert(p
!= this->warnings_
.end());
3643 gold_warning_at_location(relinfo
, relnum
, reloffset
,
3644 "%s", p
->second
.text
.c_str());
3647 // Instantiate the templates we need. We could use the configure
3648 // script to restrict this to only the ones needed for implemented
3651 #if defined(HAVE_TARGET_32_LITTLE) || defined(HAVE_TARGET_32_BIG)
3654 Sized_symbol
<32>::allocate_common(Output_data
*, Value_type
);
3657 #if defined(HAVE_TARGET_64_LITTLE) || defined(HAVE_TARGET_64_BIG)
3660 Sized_symbol
<64>::allocate_common(Output_data
*, Value_type
);
3663 #ifdef HAVE_TARGET_32_LITTLE
3666 Symbol_table::add_from_relobj
<32, false>(
3667 Sized_relobj_file
<32, false>* relobj
,
3668 const unsigned char* syms
,
3670 size_t symndx_offset
,
3671 const char* sym_names
,
3672 size_t sym_name_size
,
3673 Sized_relobj_file
<32, false>::Symbols
* sympointers
,
3677 #ifdef HAVE_TARGET_32_BIG
3680 Symbol_table::add_from_relobj
<32, true>(
3681 Sized_relobj_file
<32, true>* relobj
,
3682 const unsigned char* syms
,
3684 size_t symndx_offset
,
3685 const char* sym_names
,
3686 size_t sym_name_size
,
3687 Sized_relobj_file
<32, true>::Symbols
* sympointers
,
3691 #ifdef HAVE_TARGET_64_LITTLE
3694 Symbol_table::add_from_relobj
<64, false>(
3695 Sized_relobj_file
<64, false>* relobj
,
3696 const unsigned char* syms
,
3698 size_t symndx_offset
,
3699 const char* sym_names
,
3700 size_t sym_name_size
,
3701 Sized_relobj_file
<64, false>::Symbols
* sympointers
,
3705 #ifdef HAVE_TARGET_64_BIG
3708 Symbol_table::add_from_relobj
<64, true>(
3709 Sized_relobj_file
<64, true>* relobj
,
3710 const unsigned char* syms
,
3712 size_t symndx_offset
,
3713 const char* sym_names
,
3714 size_t sym_name_size
,
3715 Sized_relobj_file
<64, true>::Symbols
* sympointers
,
3719 #ifdef HAVE_TARGET_32_LITTLE
3722 Symbol_table::add_from_pluginobj
<32, false>(
3723 Sized_pluginobj
<32, false>* obj
,
3726 elfcpp::Sym
<32, false>* sym
);
3729 #ifdef HAVE_TARGET_32_BIG
3732 Symbol_table::add_from_pluginobj
<32, true>(
3733 Sized_pluginobj
<32, true>* obj
,
3736 elfcpp::Sym
<32, true>* sym
);
3739 #ifdef HAVE_TARGET_64_LITTLE
3742 Symbol_table::add_from_pluginobj
<64, false>(
3743 Sized_pluginobj
<64, false>* obj
,
3746 elfcpp::Sym
<64, false>* sym
);
3749 #ifdef HAVE_TARGET_64_BIG
3752 Symbol_table::add_from_pluginobj
<64, true>(
3753 Sized_pluginobj
<64, true>* obj
,
3756 elfcpp::Sym
<64, true>* sym
);
3759 #ifdef HAVE_TARGET_32_LITTLE
3762 Symbol_table::add_from_dynobj
<32, false>(
3763 Sized_dynobj
<32, false>* dynobj
,
3764 const unsigned char* syms
,
3766 const char* sym_names
,
3767 size_t sym_name_size
,
3768 const unsigned char* versym
,
3770 const std::vector
<const char*>* version_map
,
3771 Sized_relobj_file
<32, false>::Symbols
* sympointers
,
3775 #ifdef HAVE_TARGET_32_BIG
3778 Symbol_table::add_from_dynobj
<32, true>(
3779 Sized_dynobj
<32, true>* dynobj
,
3780 const unsigned char* syms
,
3782 const char* sym_names
,
3783 size_t sym_name_size
,
3784 const unsigned char* versym
,
3786 const std::vector
<const char*>* version_map
,
3787 Sized_relobj_file
<32, true>::Symbols
* sympointers
,
3791 #ifdef HAVE_TARGET_64_LITTLE
3794 Symbol_table::add_from_dynobj
<64, false>(
3795 Sized_dynobj
<64, false>* dynobj
,
3796 const unsigned char* syms
,
3798 const char* sym_names
,
3799 size_t sym_name_size
,
3800 const unsigned char* versym
,
3802 const std::vector
<const char*>* version_map
,
3803 Sized_relobj_file
<64, false>::Symbols
* sympointers
,
3807 #ifdef HAVE_TARGET_64_BIG
3810 Symbol_table::add_from_dynobj
<64, true>(
3811 Sized_dynobj
<64, true>* dynobj
,
3812 const unsigned char* syms
,
3814 const char* sym_names
,
3815 size_t sym_name_size
,
3816 const unsigned char* versym
,
3818 const std::vector
<const char*>* version_map
,
3819 Sized_relobj_file
<64, true>::Symbols
* sympointers
,
3823 #ifdef HAVE_TARGET_32_LITTLE
3826 Symbol_table::add_from_incrobj(
3830 elfcpp::Sym
<32, false>* sym
);
3833 #ifdef HAVE_TARGET_32_BIG
3836 Symbol_table::add_from_incrobj(
3840 elfcpp::Sym
<32, true>* sym
);
3843 #ifdef HAVE_TARGET_64_LITTLE
3846 Symbol_table::add_from_incrobj(
3850 elfcpp::Sym
<64, false>* sym
);
3853 #ifdef HAVE_TARGET_64_BIG
3856 Symbol_table::add_from_incrobj(
3860 elfcpp::Sym
<64, true>* sym
);
3863 #if defined(HAVE_TARGET_32_LITTLE) || defined(HAVE_TARGET_32_BIG)
3866 Symbol_table::define_with_copy_reloc
<32>(
3867 Sized_symbol
<32>* sym
,
3869 elfcpp::Elf_types
<32>::Elf_Addr value
);
3872 #if defined(HAVE_TARGET_64_LITTLE) || defined(HAVE_TARGET_64_BIG)
3875 Symbol_table::define_with_copy_reloc
<64>(
3876 Sized_symbol
<64>* sym
,
3878 elfcpp::Elf_types
<64>::Elf_Addr value
);
3881 #if defined(HAVE_TARGET_32_LITTLE) || defined(HAVE_TARGET_32_BIG)
3884 Sized_symbol
<32>::init_output_data(const char* name
, const char* version
,
3885 Output_data
* od
, Value_type value
,
3886 Size_type symsize
, elfcpp::STT type
,
3887 elfcpp::STB binding
,
3888 elfcpp::STV visibility
,
3889 unsigned char nonvis
,
3890 bool offset_is_from_end
,
3891 bool is_predefined
);
3895 Sized_symbol
<32>::init_constant(const char* name
, const char* version
,
3896 Value_type value
, Size_type symsize
,
3897 elfcpp::STT type
, elfcpp::STB binding
,
3898 elfcpp::STV visibility
, unsigned char nonvis
,
3899 bool is_predefined
);
3903 Sized_symbol
<32>::init_undefined(const char* name
, const char* version
,
3904 Value_type value
, elfcpp::STT type
,
3905 elfcpp::STB binding
, elfcpp::STV visibility
,
3906 unsigned char nonvis
);
3909 #if defined(HAVE_TARGET_64_LITTLE) || defined(HAVE_TARGET_64_BIG)
3912 Sized_symbol
<64>::init_output_data(const char* name
, const char* version
,
3913 Output_data
* od
, Value_type value
,
3914 Size_type symsize
, elfcpp::STT type
,
3915 elfcpp::STB binding
,
3916 elfcpp::STV visibility
,
3917 unsigned char nonvis
,
3918 bool offset_is_from_end
,
3919 bool is_predefined
);
3923 Sized_symbol
<64>::init_constant(const char* name
, const char* version
,
3924 Value_type value
, Size_type symsize
,
3925 elfcpp::STT type
, elfcpp::STB binding
,
3926 elfcpp::STV visibility
, unsigned char nonvis
,
3927 bool is_predefined
);
3931 Sized_symbol
<64>::init_undefined(const char* name
, const char* version
,
3932 Value_type value
, elfcpp::STT type
,
3933 elfcpp::STB binding
, elfcpp::STV visibility
,
3934 unsigned char nonvis
);
3937 #ifdef HAVE_TARGET_32_LITTLE
3940 Warnings::issue_warning
<32, false>(const Symbol
* sym
,
3941 const Relocate_info
<32, false>* relinfo
,
3942 size_t relnum
, off_t reloffset
) const;
3945 #ifdef HAVE_TARGET_32_BIG
3948 Warnings::issue_warning
<32, true>(const Symbol
* sym
,
3949 const Relocate_info
<32, true>* relinfo
,
3950 size_t relnum
, off_t reloffset
) const;
3953 #ifdef HAVE_TARGET_64_LITTLE
3956 Warnings::issue_warning
<64, false>(const Symbol
* sym
,
3957 const Relocate_info
<64, false>* relinfo
,
3958 size_t relnum
, off_t reloffset
) const;
3961 #ifdef HAVE_TARGET_64_BIG
3964 Warnings::issue_warning
<64, true>(const Symbol
* sym
,
3965 const Relocate_info
<64, true>* relinfo
,
3966 size_t relnum
, off_t reloffset
) const;
3969 } // End namespace gold.