1 // symtab.cc -- the gold symbol table
3 // Copyright 2006, 2007, 2008 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.
32 #include "dwarf_reader.h"
36 #include "workqueue.h"
44 // Initialize fields in Symbol. This initializes everything except u_
48 Symbol::init_fields(const char* name
, const char* version
,
49 elfcpp::STT type
, elfcpp::STB binding
,
50 elfcpp::STV visibility
, unsigned char nonvis
)
53 this->version_
= version
;
54 this->symtab_index_
= 0;
55 this->dynsym_index_
= 0;
56 this->got_offset_
= 0;
57 this->plt_offset_
= 0;
59 this->binding_
= binding
;
60 this->visibility_
= visibility
;
61 this->nonvis_
= nonvis
;
62 this->is_target_special_
= false;
63 this->is_def_
= false;
64 this->is_forwarder_
= false;
65 this->has_alias_
= false;
66 this->needs_dynsym_entry_
= false;
67 this->in_reg_
= false;
68 this->in_dyn_
= false;
69 this->has_got_offset_
= false;
70 this->has_plt_offset_
= false;
71 this->has_warning_
= false;
72 this->is_copied_from_dynobj_
= false;
73 this->is_forced_local_
= false;
76 // Return the demangled version of the symbol's name, but only
77 // if the --demangle flag was set.
80 demangle(const char* name
)
82 if (!parameters
->demangle())
85 // cplus_demangle allocates memory for the result it returns,
86 // and returns NULL if the name is already demangled.
87 char* demangled_name
= cplus_demangle(name
, DMGL_ANSI
| DMGL_PARAMS
);
88 if (demangled_name
== NULL
)
91 std::string
retval(demangled_name
);
97 Symbol::demangled_name() const
99 return demangle(this->name());
102 // Initialize the fields in the base class Symbol for SYM in OBJECT.
104 template<int size
, bool big_endian
>
106 Symbol::init_base(const char* name
, const char* version
, Object
* object
,
107 const elfcpp::Sym
<size
, big_endian
>& sym
)
109 this->init_fields(name
, version
, sym
.get_st_type(), sym
.get_st_bind(),
110 sym
.get_st_visibility(), sym
.get_st_nonvis());
111 this->u_
.from_object
.object
= object
;
112 // FIXME: Handle SHN_XINDEX.
113 this->u_
.from_object
.shndx
= sym
.get_st_shndx();
114 this->source_
= FROM_OBJECT
;
115 this->in_reg_
= !object
->is_dynamic();
116 this->in_dyn_
= object
->is_dynamic();
119 // Initialize the fields in the base class Symbol for a symbol defined
120 // in an Output_data.
123 Symbol::init_base(const char* name
, Output_data
* od
, elfcpp::STT type
,
124 elfcpp::STB binding
, elfcpp::STV visibility
,
125 unsigned char nonvis
, bool offset_is_from_end
)
127 this->init_fields(name
, NULL
, type
, binding
, visibility
, nonvis
);
128 this->u_
.in_output_data
.output_data
= od
;
129 this->u_
.in_output_data
.offset_is_from_end
= offset_is_from_end
;
130 this->source_
= IN_OUTPUT_DATA
;
131 this->in_reg_
= true;
134 // Initialize the fields in the base class Symbol for a symbol defined
135 // in an Output_segment.
138 Symbol::init_base(const char* name
, Output_segment
* os
, elfcpp::STT type
,
139 elfcpp::STB binding
, elfcpp::STV visibility
,
140 unsigned char nonvis
, Segment_offset_base offset_base
)
142 this->init_fields(name
, NULL
, type
, binding
, visibility
, nonvis
);
143 this->u_
.in_output_segment
.output_segment
= os
;
144 this->u_
.in_output_segment
.offset_base
= offset_base
;
145 this->source_
= IN_OUTPUT_SEGMENT
;
146 this->in_reg_
= true;
149 // Initialize the fields in the base class Symbol for a symbol defined
153 Symbol::init_base(const char* name
, elfcpp::STT type
,
154 elfcpp::STB binding
, elfcpp::STV visibility
,
155 unsigned char nonvis
)
157 this->init_fields(name
, NULL
, type
, binding
, visibility
, nonvis
);
158 this->source_
= CONSTANT
;
159 this->in_reg_
= true;
162 // Allocate a common symbol in the base.
165 Symbol::allocate_base_common(Output_data
* od
)
167 gold_assert(this->is_common());
168 this->source_
= IN_OUTPUT_DATA
;
169 this->u_
.in_output_data
.output_data
= od
;
170 this->u_
.in_output_data
.offset_is_from_end
= false;
173 // Initialize the fields in Sized_symbol for SYM in OBJECT.
176 template<bool big_endian
>
178 Sized_symbol
<size
>::init(const char* name
, const char* version
, Object
* object
,
179 const elfcpp::Sym
<size
, big_endian
>& sym
)
181 this->init_base(name
, version
, object
, sym
);
182 this->value_
= sym
.get_st_value();
183 this->symsize_
= sym
.get_st_size();
186 // Initialize the fields in Sized_symbol for a symbol defined in an
191 Sized_symbol
<size
>::init(const char* name
, Output_data
* od
,
192 Value_type value
, Size_type symsize
,
193 elfcpp::STT type
, elfcpp::STB binding
,
194 elfcpp::STV visibility
, unsigned char nonvis
,
195 bool offset_is_from_end
)
197 this->init_base(name
, od
, type
, binding
, visibility
, nonvis
,
199 this->value_
= value
;
200 this->symsize_
= symsize
;
203 // Initialize the fields in Sized_symbol for a symbol defined in an
208 Sized_symbol
<size
>::init(const char* name
, Output_segment
* os
,
209 Value_type value
, Size_type symsize
,
210 elfcpp::STT type
, elfcpp::STB binding
,
211 elfcpp::STV visibility
, unsigned char nonvis
,
212 Segment_offset_base offset_base
)
214 this->init_base(name
, os
, type
, binding
, visibility
, nonvis
, offset_base
);
215 this->value_
= value
;
216 this->symsize_
= symsize
;
219 // Initialize the fields in Sized_symbol for a symbol defined as a
224 Sized_symbol
<size
>::init(const char* name
, Value_type value
, Size_type symsize
,
225 elfcpp::STT type
, elfcpp::STB binding
,
226 elfcpp::STV visibility
, unsigned char nonvis
)
228 this->init_base(name
, type
, binding
, visibility
, nonvis
);
229 this->value_
= value
;
230 this->symsize_
= symsize
;
233 // Allocate a common symbol.
237 Sized_symbol
<size
>::allocate_common(Output_data
* od
, Value_type value
)
239 this->allocate_base_common(od
);
240 this->value_
= value
;
243 // Return true if this symbol should be added to the dynamic symbol
247 Symbol::should_add_dynsym_entry() const
249 // If the symbol is used by a dynamic relocation, we need to add it.
250 if (this->needs_dynsym_entry())
253 // If the symbol was forced local in a version script, do not add it.
254 if (this->is_forced_local())
257 // If exporting all symbols or building a shared library,
258 // and the symbol is defined in a regular object and is
259 // externally visible, we need to add it.
260 if ((parameters
->export_dynamic() || parameters
->output_is_shared())
261 && !this->is_from_dynobj()
262 && this->is_externally_visible())
268 // Return true if the final value of this symbol is known at link
272 Symbol::final_value_is_known() const
274 // If we are not generating an executable, then no final values are
275 // known, since they will change at runtime.
276 if (!parameters
->output_is_executable())
279 // If the symbol is not from an object file, then it is defined, and
281 if (this->source_
!= FROM_OBJECT
)
284 // If the symbol is from a dynamic object, then the final value is
286 if (this->object()->is_dynamic())
289 // If the symbol is not undefined (it is defined or common), then
290 // the final value is known.
291 if (!this->is_undefined())
294 // If the symbol is undefined, then whether the final value is known
295 // depends on whether we are doing a static link. If we are doing a
296 // dynamic link, then the final value could be filled in at runtime.
297 // This could reasonably be the case for a weak undefined symbol.
298 return parameters
->doing_static_link();
301 // Class Symbol_table.
303 Symbol_table::Symbol_table(unsigned int count
,
304 const Version_script_info
& version_script
)
305 : saw_undefined_(0), offset_(0), table_(count
), namepool_(),
306 forwarders_(), commons_(), forced_locals_(), warnings_(),
307 version_script_(version_script
)
309 namepool_
.reserve(count
);
312 Symbol_table::~Symbol_table()
316 // The hash function. The key values are Stringpool keys.
319 Symbol_table::Symbol_table_hash::operator()(const Symbol_table_key
& key
) const
321 return key
.first
^ key
.second
;
324 // The symbol table key equality function. This is called with
328 Symbol_table::Symbol_table_eq::operator()(const Symbol_table_key
& k1
,
329 const Symbol_table_key
& k2
) const
331 return k1
.first
== k2
.first
&& k1
.second
== k2
.second
;
334 // Make TO a symbol which forwards to FROM.
337 Symbol_table::make_forwarder(Symbol
* from
, Symbol
* to
)
339 gold_assert(from
!= to
);
340 gold_assert(!from
->is_forwarder() && !to
->is_forwarder());
341 this->forwarders_
[from
] = to
;
342 from
->set_forwarder();
345 // Resolve the forwards from FROM, returning the real symbol.
348 Symbol_table::resolve_forwards(const Symbol
* from
) const
350 gold_assert(from
->is_forwarder());
351 Unordered_map
<const Symbol
*, Symbol
*>::const_iterator p
=
352 this->forwarders_
.find(from
);
353 gold_assert(p
!= this->forwarders_
.end());
357 // Look up a symbol by name.
360 Symbol_table::lookup(const char* name
, const char* version
) const
362 Stringpool::Key name_key
;
363 name
= this->namepool_
.find(name
, &name_key
);
367 Stringpool::Key version_key
= 0;
370 version
= this->namepool_
.find(version
, &version_key
);
375 Symbol_table_key
key(name_key
, version_key
);
376 Symbol_table::Symbol_table_type::const_iterator p
= this->table_
.find(key
);
377 if (p
== this->table_
.end())
382 // Resolve a Symbol with another Symbol. This is only used in the
383 // unusual case where there are references to both an unversioned
384 // symbol and a symbol with a version, and we then discover that that
385 // version is the default version. Because this is unusual, we do
386 // this the slow way, by converting back to an ELF symbol.
388 template<int size
, bool big_endian
>
390 Symbol_table::resolve(Sized_symbol
<size
>* to
, const Sized_symbol
<size
>* from
,
391 const char* version ACCEPT_SIZE_ENDIAN
)
393 unsigned char buf
[elfcpp::Elf_sizes
<size
>::sym_size
];
394 elfcpp::Sym_write
<size
, big_endian
> esym(buf
);
395 // We don't bother to set the st_name field.
396 esym
.put_st_value(from
->value());
397 esym
.put_st_size(from
->symsize());
398 esym
.put_st_info(from
->binding(), from
->type());
399 esym
.put_st_other(from
->visibility(), from
->nonvis());
400 esym
.put_st_shndx(from
->shndx());
401 this->resolve(to
, esym
.sym(), esym
.sym(), from
->object(), version
);
408 // Record that a symbol is forced to be local by a version script.
411 Symbol_table::force_local(Symbol
* sym
)
413 if (!sym
->is_defined() && !sym
->is_common())
415 if (sym
->is_forced_local())
417 // We already got this one.
420 sym
->set_is_forced_local();
421 this->forced_locals_
.push_back(sym
);
424 // Add one symbol from OBJECT to the symbol table. NAME is symbol
425 // name and VERSION is the version; both are canonicalized. DEF is
426 // whether this is the default version.
428 // If DEF is true, then this is the definition of a default version of
429 // a symbol. That means that any lookup of NAME/NULL and any lookup
430 // of NAME/VERSION should always return the same symbol. This is
431 // obvious for references, but in particular we want to do this for
432 // definitions: overriding NAME/NULL should also override
433 // NAME/VERSION. If we don't do that, it would be very hard to
434 // override functions in a shared library which uses versioning.
436 // We implement this by simply making both entries in the hash table
437 // point to the same Symbol structure. That is easy enough if this is
438 // the first time we see NAME/NULL or NAME/VERSION, but it is possible
439 // that we have seen both already, in which case they will both have
440 // independent entries in the symbol table. We can't simply change
441 // the symbol table entry, because we have pointers to the entries
442 // attached to the object files. So we mark the entry attached to the
443 // object file as a forwarder, and record it in the forwarders_ map.
444 // Note that entries in the hash table will never be marked as
447 // SYM and ORIG_SYM are almost always the same. ORIG_SYM is the
448 // symbol exactly as it existed in the input file. SYM is usually
449 // that as well, but can be modified, for instance if we determine
450 // it's in a to-be-discarded section.
452 template<int size
, bool big_endian
>
454 Symbol_table::add_from_object(Object
* object
,
456 Stringpool::Key name_key
,
458 Stringpool::Key version_key
,
460 const elfcpp::Sym
<size
, big_endian
>& sym
,
461 const elfcpp::Sym
<size
, big_endian
>& orig_sym
)
463 Symbol
* const snull
= NULL
;
464 std::pair
<typename
Symbol_table_type::iterator
, bool> ins
=
465 this->table_
.insert(std::make_pair(std::make_pair(name_key
, version_key
),
468 std::pair
<typename
Symbol_table_type::iterator
, bool> insdef
=
469 std::make_pair(this->table_
.end(), false);
472 const Stringpool::Key vnull_key
= 0;
473 insdef
= this->table_
.insert(std::make_pair(std::make_pair(name_key
,
478 // ins.first: an iterator, which is a pointer to a pair.
479 // ins.first->first: the key (a pair of name and version).
480 // ins.first->second: the value (Symbol*).
481 // ins.second: true if new entry was inserted, false if not.
483 Sized_symbol
<size
>* ret
;
488 // We already have an entry for NAME/VERSION.
489 ret
= this->get_sized_symbol
SELECT_SIZE_NAME(size
) (ins
.first
->second
491 gold_assert(ret
!= NULL
);
493 was_undefined
= ret
->is_undefined();
494 was_common
= ret
->is_common();
496 this->resolve(ret
, sym
, orig_sym
, object
, version
);
502 // This is the first time we have seen NAME/NULL. Make
503 // NAME/NULL point to NAME/VERSION.
504 insdef
.first
->second
= ret
;
506 else if (insdef
.first
->second
!= ret
507 && insdef
.first
->second
->is_undefined())
509 // This is the unfortunate case where we already have
510 // entries for both NAME/VERSION and NAME/NULL. Note
511 // that we don't want to combine them if the existing
512 // symbol is going to override the new one. FIXME: We
513 // currently just test is_undefined, but this may not do
514 // the right thing if the existing symbol is from a
515 // shared library and the new one is from a regular
518 const Sized_symbol
<size
>* sym2
;
519 sym2
= this->get_sized_symbol
SELECT_SIZE_NAME(size
) (
522 Symbol_table::resolve
SELECT_SIZE_ENDIAN_NAME(size
, big_endian
) (
523 ret
, sym2
, version
SELECT_SIZE_ENDIAN(size
, big_endian
));
524 this->make_forwarder(insdef
.first
->second
, ret
);
525 insdef
.first
->second
= ret
;
531 // This is the first time we have seen NAME/VERSION.
532 gold_assert(ins
.first
->second
== NULL
);
534 was_undefined
= false;
537 if (def
&& !insdef
.second
)
539 // We already have an entry for NAME/NULL. If we override
540 // it, then change it to NAME/VERSION.
541 ret
= this->get_sized_symbol
SELECT_SIZE_NAME(size
) (
544 this->resolve(ret
, sym
, orig_sym
, object
, version
);
545 ins
.first
->second
= ret
;
549 Sized_target
<size
, big_endian
>* target
=
550 object
->sized_target
SELECT_SIZE_ENDIAN_NAME(size
, big_endian
) (
551 SELECT_SIZE_ENDIAN_ONLY(size
, big_endian
));
552 if (!target
->has_make_symbol())
553 ret
= new Sized_symbol
<size
>();
556 ret
= target
->make_symbol();
559 // This means that we don't want a symbol table
562 this->table_
.erase(ins
.first
);
565 this->table_
.erase(insdef
.first
);
566 // Inserting insdef invalidated ins.
567 this->table_
.erase(std::make_pair(name_key
,
574 ret
->init(name
, version
, object
, sym
);
576 ins
.first
->second
= ret
;
579 // This is the first time we have seen NAME/NULL. Point
580 // it at the new entry for NAME/VERSION.
581 gold_assert(insdef
.second
);
582 insdef
.first
->second
= ret
;
587 // Record every time we see a new undefined symbol, to speed up
589 if (!was_undefined
&& ret
->is_undefined())
590 ++this->saw_undefined_
;
592 // Keep track of common symbols, to speed up common symbol
594 if (!was_common
&& ret
->is_common())
595 this->commons_
.push_back(ret
);
597 ret
->set_is_default(def
);
601 // Add all the symbols in a relocatable object to the hash table.
603 template<int size
, bool big_endian
>
605 Symbol_table::add_from_relobj(
606 Sized_relobj
<size
, big_endian
>* relobj
,
607 const unsigned char* syms
,
609 const char* sym_names
,
610 size_t sym_name_size
,
611 typename Sized_relobj
<size
, big_endian
>::Symbols
* sympointers
)
613 gold_assert(size
== relobj
->target()->get_size());
614 gold_assert(size
== parameters
->get_size());
616 const int sym_size
= elfcpp::Elf_sizes
<size
>::sym_size
;
618 const unsigned char* p
= syms
;
619 for (size_t i
= 0; i
< count
; ++i
, p
+= sym_size
)
621 elfcpp::Sym
<size
, big_endian
> sym(p
);
622 elfcpp::Sym
<size
, big_endian
>* psym
= &sym
;
624 unsigned int st_name
= psym
->get_st_name();
625 if (st_name
>= sym_name_size
)
627 relobj
->error(_("bad global symbol name offset %u at %zu"),
632 const char* name
= sym_names
+ st_name
;
634 // A symbol defined in a section which we are not including must
635 // be treated as an undefined symbol.
636 unsigned char symbuf
[sym_size
];
637 elfcpp::Sym
<size
, big_endian
> sym2(symbuf
);
638 unsigned int st_shndx
= psym
->get_st_shndx();
639 if (st_shndx
!= elfcpp::SHN_UNDEF
640 && st_shndx
< elfcpp::SHN_LORESERVE
641 && !relobj
->is_section_included(st_shndx
))
643 memcpy(symbuf
, p
, sym_size
);
644 elfcpp::Sym_write
<size
, big_endian
> sw(symbuf
);
645 sw
.put_st_shndx(elfcpp::SHN_UNDEF
);
649 // In an object file, an '@' in the name separates the symbol
650 // name from the version name. If there are two '@' characters,
651 // this is the default version.
652 const char* ver
= strchr(name
, '@');
654 // DEF: is the version default? LOCAL: is the symbol forced local?
660 // The symbol name is of the form foo@VERSION or foo@@VERSION
661 namelen
= ver
- name
;
669 else if (!version_script_
.empty())
671 // The symbol name did not have a version, but
672 // the version script may assign a version anyway.
673 namelen
= strlen(name
);
675 // Check the global: entries from the version script.
676 const std::string
& version
=
677 version_script_
.get_symbol_version(name
);
678 if (!version
.empty())
679 ver
= version
.c_str();
680 // Check the local: entries from the version script
681 if (version_script_
.symbol_is_local(name
))
685 Sized_symbol
<size
>* res
;
688 Stringpool::Key name_key
;
689 name
= this->namepool_
.add(name
, true, &name_key
);
690 res
= this->add_from_object(relobj
, name
, name_key
, NULL
, 0,
693 this->force_local(res
);
697 Stringpool::Key name_key
;
698 name
= this->namepool_
.add_with_length(name
, namelen
, true,
700 Stringpool::Key ver_key
;
701 ver
= this->namepool_
.add(ver
, true, &ver_key
);
703 res
= this->add_from_object(relobj
, name
, name_key
, ver
, ver_key
,
707 (*sympointers
)[i
] = res
;
711 // Add all the symbols in a dynamic object to the hash table.
713 template<int size
, bool big_endian
>
715 Symbol_table::add_from_dynobj(
716 Sized_dynobj
<size
, big_endian
>* dynobj
,
717 const unsigned char* syms
,
719 const char* sym_names
,
720 size_t sym_name_size
,
721 const unsigned char* versym
,
723 const std::vector
<const char*>* version_map
)
725 gold_assert(size
== dynobj
->target()->get_size());
726 gold_assert(size
== parameters
->get_size());
728 if (versym
!= NULL
&& versym_size
/ 2 < count
)
730 dynobj
->error(_("too few symbol versions"));
734 const int sym_size
= elfcpp::Elf_sizes
<size
>::sym_size
;
736 // We keep a list of all STT_OBJECT symbols, so that we can resolve
737 // weak aliases. This is necessary because if the dynamic object
738 // provides the same variable under two names, one of which is a
739 // weak definition, and the regular object refers to the weak
740 // definition, we have to put both the weak definition and the
741 // strong definition into the dynamic symbol table. Given a weak
742 // definition, the only way that we can find the corresponding
743 // strong definition, if any, is to search the symbol table.
744 std::vector
<Sized_symbol
<size
>*> object_symbols
;
746 const unsigned char* p
= syms
;
747 const unsigned char* vs
= versym
;
748 for (size_t i
= 0; i
< count
; ++i
, p
+= sym_size
, vs
+= 2)
750 elfcpp::Sym
<size
, big_endian
> sym(p
);
752 // Ignore symbols with local binding.
753 if (sym
.get_st_bind() == elfcpp::STB_LOCAL
)
756 unsigned int st_name
= sym
.get_st_name();
757 if (st_name
>= sym_name_size
)
759 dynobj
->error(_("bad symbol name offset %u at %zu"),
764 const char* name
= sym_names
+ st_name
;
766 Sized_symbol
<size
>* res
;
770 Stringpool::Key name_key
;
771 name
= this->namepool_
.add(name
, true, &name_key
);
772 res
= this->add_from_object(dynobj
, name
, name_key
, NULL
, 0,
777 // Read the version information.
779 unsigned int v
= elfcpp::Swap
<16, big_endian
>::readval(vs
);
781 bool hidden
= (v
& elfcpp::VERSYM_HIDDEN
) != 0;
782 v
&= elfcpp::VERSYM_VERSION
;
784 // The Sun documentation says that V can be VER_NDX_LOCAL,
785 // or VER_NDX_GLOBAL, or a version index. The meaning of
786 // VER_NDX_LOCAL is defined as "Symbol has local scope."
787 // The old GNU linker will happily generate VER_NDX_LOCAL
788 // for an undefined symbol. I don't know what the Sun
789 // linker will generate.
791 if (v
== static_cast<unsigned int>(elfcpp::VER_NDX_LOCAL
)
792 && sym
.get_st_shndx() != elfcpp::SHN_UNDEF
)
794 // This symbol should not be visible outside the object.
798 // At this point we are definitely going to add this symbol.
799 Stringpool::Key name_key
;
800 name
= this->namepool_
.add(name
, true, &name_key
);
802 if (v
== static_cast<unsigned int>(elfcpp::VER_NDX_LOCAL
)
803 || v
== static_cast<unsigned int>(elfcpp::VER_NDX_GLOBAL
))
805 // This symbol does not have a version.
806 res
= this->add_from_object(dynobj
, name
, name_key
, NULL
, 0,
811 if (v
>= version_map
->size())
813 dynobj
->error(_("versym for symbol %zu out of range: %u"),
818 const char* version
= (*version_map
)[v
];
821 dynobj
->error(_("versym for symbol %zu has no name: %u"),
826 Stringpool::Key version_key
;
827 version
= this->namepool_
.add(version
, true, &version_key
);
829 // If this is an absolute symbol, and the version name
830 // and symbol name are the same, then this is the
831 // version definition symbol. These symbols exist to
832 // support using -u to pull in particular versions. We
833 // do not want to record a version for them.
834 if (sym
.get_st_shndx() == elfcpp::SHN_ABS
835 && name_key
== version_key
)
836 res
= this->add_from_object(dynobj
, name
, name_key
, NULL
, 0,
840 const bool def
= (!hidden
841 && (sym
.get_st_shndx()
842 != elfcpp::SHN_UNDEF
));
843 res
= this->add_from_object(dynobj
, name
, name_key
, version
,
844 version_key
, def
, sym
, sym
);
849 if (sym
.get_st_shndx() != elfcpp::SHN_UNDEF
850 && sym
.get_st_type() == elfcpp::STT_OBJECT
)
851 object_symbols
.push_back(res
);
854 this->record_weak_aliases(&object_symbols
);
857 // This is used to sort weak aliases. We sort them first by section
858 // index, then by offset, then by weak ahead of strong.
861 class Weak_alias_sorter
864 bool operator()(const Sized_symbol
<size
>*, const Sized_symbol
<size
>*) const;
869 Weak_alias_sorter
<size
>::operator()(const Sized_symbol
<size
>* s1
,
870 const Sized_symbol
<size
>* s2
) const
872 if (s1
->shndx() != s2
->shndx())
873 return s1
->shndx() < s2
->shndx();
874 if (s1
->value() != s2
->value())
875 return s1
->value() < s2
->value();
876 if (s1
->binding() != s2
->binding())
878 if (s1
->binding() == elfcpp::STB_WEAK
)
880 if (s2
->binding() == elfcpp::STB_WEAK
)
883 return std::string(s1
->name()) < std::string(s2
->name());
886 // SYMBOLS is a list of object symbols from a dynamic object. Look
887 // for any weak aliases, and record them so that if we add the weak
888 // alias to the dynamic symbol table, we also add the corresponding
893 Symbol_table::record_weak_aliases(std::vector
<Sized_symbol
<size
>*>* symbols
)
895 // Sort the vector by section index, then by offset, then by weak
897 std::sort(symbols
->begin(), symbols
->end(), Weak_alias_sorter
<size
>());
899 // Walk through the vector. For each weak definition, record
901 for (typename
std::vector
<Sized_symbol
<size
>*>::const_iterator p
=
906 if ((*p
)->binding() != elfcpp::STB_WEAK
)
909 // Build a circular list of weak aliases. Each symbol points to
910 // the next one in the circular list.
912 Sized_symbol
<size
>* from_sym
= *p
;
913 typename
std::vector
<Sized_symbol
<size
>*>::const_iterator q
;
914 for (q
= p
+ 1; q
!= symbols
->end(); ++q
)
916 if ((*q
)->shndx() != from_sym
->shndx()
917 || (*q
)->value() != from_sym
->value())
920 this->weak_aliases_
[from_sym
] = *q
;
921 from_sym
->set_has_alias();
927 this->weak_aliases_
[from_sym
] = *p
;
928 from_sym
->set_has_alias();
935 // Create and return a specially defined symbol. If ONLY_IF_REF is
936 // true, then only create the symbol if there is a reference to it.
937 // If this does not return NULL, it sets *POLDSYM to the existing
938 // symbol if there is one. This canonicalizes *PNAME and *PVERSION.
940 template<int size
, bool big_endian
>
942 Symbol_table::define_special_symbol(const Target
* target
, const char** pname
,
943 const char** pversion
, bool only_if_ref
,
944 Sized_symbol
<size
>** poldsym
948 Sized_symbol
<size
>* sym
;
949 bool add_to_table
= false;
950 typename
Symbol_table_type::iterator add_loc
= this->table_
.end();
952 // If the caller didn't give us a version, see if we get one from
953 // the version script.
954 if (*pversion
== NULL
)
956 const std::string
& v(this->version_script_
.get_symbol_version(*pname
));
958 *pversion
= v
.c_str();
963 oldsym
= this->lookup(*pname
, *pversion
);
964 if (oldsym
== NULL
|| !oldsym
->is_undefined())
967 *pname
= oldsym
->name();
968 *pversion
= oldsym
->version();
972 // Canonicalize NAME and VERSION.
973 Stringpool::Key name_key
;
974 *pname
= this->namepool_
.add(*pname
, true, &name_key
);
976 Stringpool::Key version_key
= 0;
977 if (*pversion
!= NULL
)
978 *pversion
= this->namepool_
.add(*pversion
, true, &version_key
);
980 Symbol
* const snull
= NULL
;
981 std::pair
<typename
Symbol_table_type::iterator
, bool> ins
=
982 this->table_
.insert(std::make_pair(std::make_pair(name_key
,
988 // We already have a symbol table entry for NAME/VERSION.
989 oldsym
= ins
.first
->second
;
990 gold_assert(oldsym
!= NULL
);
994 // We haven't seen this symbol before.
995 gold_assert(ins
.first
->second
== NULL
);
1002 if (!target
->has_make_symbol())
1003 sym
= new Sized_symbol
<size
>();
1006 gold_assert(target
->get_size() == size
);
1007 gold_assert(target
->is_big_endian() ? big_endian
: !big_endian
);
1008 typedef Sized_target
<size
, big_endian
> My_target
;
1009 const My_target
* sized_target
=
1010 static_cast<const My_target
*>(target
);
1011 sym
= sized_target
->make_symbol();
1017 add_loc
->second
= sym
;
1019 gold_assert(oldsym
!= NULL
);
1021 *poldsym
= this->get_sized_symbol
SELECT_SIZE_NAME(size
) (oldsym
1027 // Define a symbol based on an Output_data.
1030 Symbol_table::define_in_output_data(const Target
* target
, const char* name
,
1031 const char* version
, Output_data
* od
,
1032 uint64_t value
, uint64_t symsize
,
1033 elfcpp::STT type
, elfcpp::STB binding
,
1034 elfcpp::STV visibility
,
1035 unsigned char nonvis
,
1036 bool offset_is_from_end
,
1039 if (parameters
->get_size() == 32)
1041 #if defined(HAVE_TARGET_32_LITTLE) || defined(HAVE_TARGET_32_BIG)
1042 return this->do_define_in_output_data
<32>(target
, name
, version
, od
,
1043 value
, symsize
, type
, binding
,
1051 else if (parameters
->get_size() == 64)
1053 #if defined(HAVE_TARGET_64_LITTLE) || defined(HAVE_TARGET_64_BIG)
1054 return this->do_define_in_output_data
<64>(target
, name
, version
, od
,
1055 value
, symsize
, type
, binding
,
1067 // Define a symbol in an Output_data, sized version.
1071 Symbol_table::do_define_in_output_data(
1072 const Target
* target
,
1074 const char* version
,
1076 typename
elfcpp::Elf_types
<size
>::Elf_Addr value
,
1077 typename
elfcpp::Elf_types
<size
>::Elf_WXword symsize
,
1079 elfcpp::STB binding
,
1080 elfcpp::STV visibility
,
1081 unsigned char nonvis
,
1082 bool offset_is_from_end
,
1085 Sized_symbol
<size
>* sym
;
1086 Sized_symbol
<size
>* oldsym
;
1088 if (parameters
->is_big_endian())
1090 #if defined(HAVE_TARGET_32_BIG) || defined(HAVE_TARGET_64_BIG)
1091 sym
= this->define_special_symbol
SELECT_SIZE_ENDIAN_NAME(size
, true) (
1092 target
, &name
, &version
, only_if_ref
, &oldsym
1093 SELECT_SIZE_ENDIAN(size
, true));
1100 #if defined(HAVE_TARGET_32_LITTLE) || defined(HAVE_TARGET_64_LITTLE)
1101 sym
= this->define_special_symbol
SELECT_SIZE_ENDIAN_NAME(size
, false) (
1102 target
, &name
, &version
, only_if_ref
, &oldsym
1103 SELECT_SIZE_ENDIAN(size
, false));
1112 gold_assert(version
== NULL
|| oldsym
!= NULL
);
1113 sym
->init(name
, od
, value
, symsize
, type
, binding
, visibility
, nonvis
,
1114 offset_is_from_end
);
1118 if (binding
== elfcpp::STB_LOCAL
1119 || this->version_script_
.symbol_is_local(name
))
1120 this->force_local(sym
);
1124 if (Symbol_table::should_override_with_special(oldsym
))
1125 this->override_with_special(oldsym
, sym
);
1130 // Define a symbol based on an Output_segment.
1133 Symbol_table::define_in_output_segment(const Target
* target
, const char* name
,
1134 const char* version
, Output_segment
* os
,
1135 uint64_t value
, uint64_t symsize
,
1136 elfcpp::STT type
, elfcpp::STB binding
,
1137 elfcpp::STV visibility
,
1138 unsigned char nonvis
,
1139 Symbol::Segment_offset_base offset_base
,
1142 if (parameters
->get_size() == 32)
1144 #if defined(HAVE_TARGET_32_LITTLE) || defined(HAVE_TARGET_32_BIG)
1145 return this->do_define_in_output_segment
<32>(target
, name
, version
, os
,
1146 value
, symsize
, type
,
1147 binding
, visibility
, nonvis
,
1148 offset_base
, only_if_ref
);
1153 else if (parameters
->get_size() == 64)
1155 #if defined(HAVE_TARGET_64_LITTLE) || defined(HAVE_TARGET_64_BIG)
1156 return this->do_define_in_output_segment
<64>(target
, name
, version
, os
,
1157 value
, symsize
, type
,
1158 binding
, visibility
, nonvis
,
1159 offset_base
, only_if_ref
);
1168 // Define a symbol in an Output_segment, sized version.
1172 Symbol_table::do_define_in_output_segment(
1173 const Target
* target
,
1175 const char* version
,
1177 typename
elfcpp::Elf_types
<size
>::Elf_Addr value
,
1178 typename
elfcpp::Elf_types
<size
>::Elf_WXword symsize
,
1180 elfcpp::STB binding
,
1181 elfcpp::STV visibility
,
1182 unsigned char nonvis
,
1183 Symbol::Segment_offset_base offset_base
,
1186 Sized_symbol
<size
>* sym
;
1187 Sized_symbol
<size
>* oldsym
;
1189 if (parameters
->is_big_endian())
1191 #if defined(HAVE_TARGET_32_BIG) || defined(HAVE_TARGET_64_BIG)
1192 sym
= this->define_special_symbol
SELECT_SIZE_ENDIAN_NAME(size
, true) (
1193 target
, &name
, &version
, only_if_ref
, &oldsym
1194 SELECT_SIZE_ENDIAN(size
, true));
1201 #if defined(HAVE_TARGET_32_LITTLE) || defined(HAVE_TARGET_64_LITTLE)
1202 sym
= this->define_special_symbol
SELECT_SIZE_ENDIAN_NAME(size
, false) (
1203 target
, &name
, &version
, only_if_ref
, &oldsym
1204 SELECT_SIZE_ENDIAN(size
, false));
1213 gold_assert(version
== NULL
|| oldsym
!= NULL
);
1214 sym
->init(name
, os
, value
, symsize
, type
, binding
, visibility
, nonvis
,
1219 if (binding
== elfcpp::STB_LOCAL
1220 || this->version_script_
.symbol_is_local(name
))
1221 this->force_local(sym
);
1225 if (Symbol_table::should_override_with_special(oldsym
))
1226 this->override_with_special(oldsym
, sym
);
1231 // Define a special symbol with a constant value. It is a multiple
1232 // definition error if this symbol is already defined.
1235 Symbol_table::define_as_constant(const Target
* target
, const char* name
,
1236 const char* version
, uint64_t value
,
1237 uint64_t symsize
, elfcpp::STT type
,
1238 elfcpp::STB binding
, elfcpp::STV visibility
,
1239 unsigned char nonvis
, bool only_if_ref
)
1241 if (parameters
->get_size() == 32)
1243 #if defined(HAVE_TARGET_32_LITTLE) || defined(HAVE_TARGET_32_BIG)
1244 return this->do_define_as_constant
<32>(target
, name
, version
, value
,
1245 symsize
, type
, binding
,
1246 visibility
, nonvis
, only_if_ref
);
1251 else if (parameters
->get_size() == 64)
1253 #if defined(HAVE_TARGET_64_LITTLE) || defined(HAVE_TARGET_64_BIG)
1254 return this->do_define_as_constant
<64>(target
, name
, version
, value
,
1255 symsize
, type
, binding
,
1256 visibility
, nonvis
, only_if_ref
);
1265 // Define a symbol as a constant, sized version.
1269 Symbol_table::do_define_as_constant(
1270 const Target
* target
,
1272 const char* version
,
1273 typename
elfcpp::Elf_types
<size
>::Elf_Addr value
,
1274 typename
elfcpp::Elf_types
<size
>::Elf_WXword symsize
,
1276 elfcpp::STB binding
,
1277 elfcpp::STV visibility
,
1278 unsigned char nonvis
,
1281 Sized_symbol
<size
>* sym
;
1282 Sized_symbol
<size
>* oldsym
;
1284 if (parameters
->is_big_endian())
1286 #if defined(HAVE_TARGET_32_BIG) || defined(HAVE_TARGET_64_BIG)
1287 sym
= this->define_special_symbol
SELECT_SIZE_ENDIAN_NAME(size
, true) (
1288 target
, &name
, &version
, only_if_ref
, &oldsym
1289 SELECT_SIZE_ENDIAN(size
, true));
1296 #if defined(HAVE_TARGET_32_LITTLE) || defined(HAVE_TARGET_64_LITTLE)
1297 sym
= this->define_special_symbol
SELECT_SIZE_ENDIAN_NAME(size
, false) (
1298 target
, &name
, &version
, only_if_ref
, &oldsym
1299 SELECT_SIZE_ENDIAN(size
, false));
1308 gold_assert(version
== NULL
|| version
== name
|| oldsym
!= NULL
);
1309 sym
->init(name
, value
, symsize
, type
, binding
, visibility
, nonvis
);
1313 if (binding
== elfcpp::STB_LOCAL
1314 || this->version_script_
.symbol_is_local(name
))
1315 this->force_local(sym
);
1319 if (Symbol_table::should_override_with_special(oldsym
))
1320 this->override_with_special(oldsym
, sym
);
1325 // Define a set of symbols in output sections.
1328 Symbol_table::define_symbols(const Layout
* layout
, const Target
* target
,
1329 int count
, const Define_symbol_in_section
* p
)
1331 for (int i
= 0; i
< count
; ++i
, ++p
)
1333 Output_section
* os
= layout
->find_output_section(p
->output_section
);
1335 this->define_in_output_data(target
, p
->name
, NULL
, os
, p
->value
,
1336 p
->size
, p
->type
, p
->binding
,
1337 p
->visibility
, p
->nonvis
,
1338 p
->offset_is_from_end
, p
->only_if_ref
);
1340 this->define_as_constant(target
, p
->name
, NULL
, 0, p
->size
, p
->type
,
1341 p
->binding
, p
->visibility
, p
->nonvis
,
1346 // Define a set of symbols in output segments.
1349 Symbol_table::define_symbols(const Layout
* layout
, const Target
* target
,
1350 int count
, const Define_symbol_in_segment
* p
)
1352 for (int i
= 0; i
< count
; ++i
, ++p
)
1354 Output_segment
* os
= layout
->find_output_segment(p
->segment_type
,
1355 p
->segment_flags_set
,
1356 p
->segment_flags_clear
);
1358 this->define_in_output_segment(target
, p
->name
, NULL
, os
, p
->value
,
1359 p
->size
, p
->type
, p
->binding
,
1360 p
->visibility
, p
->nonvis
,
1361 p
->offset_base
, p
->only_if_ref
);
1363 this->define_as_constant(target
, p
->name
, NULL
, 0, p
->size
, p
->type
,
1364 p
->binding
, p
->visibility
, p
->nonvis
,
1369 // Define CSYM using a COPY reloc. POSD is the Output_data where the
1370 // symbol should be defined--typically a .dyn.bss section. VALUE is
1371 // the offset within POSD.
1375 Symbol_table::define_with_copy_reloc(
1376 const Target
* target
,
1377 Sized_symbol
<size
>* csym
,
1379 typename
elfcpp::Elf_types
<size
>::Elf_Addr value
)
1381 gold_assert(csym
->is_from_dynobj());
1382 gold_assert(!csym
->is_copied_from_dynobj());
1383 Object
* object
= csym
->object();
1384 gold_assert(object
->is_dynamic());
1385 Dynobj
* dynobj
= static_cast<Dynobj
*>(object
);
1387 // Our copied variable has to override any variable in a shared
1389 elfcpp::STB binding
= csym
->binding();
1390 if (binding
== elfcpp::STB_WEAK
)
1391 binding
= elfcpp::STB_GLOBAL
;
1393 this->define_in_output_data(target
, csym
->name(), csym
->version(),
1394 posd
, value
, csym
->symsize(),
1395 csym
->type(), binding
,
1396 csym
->visibility(), csym
->nonvis(),
1399 csym
->set_is_copied_from_dynobj();
1400 csym
->set_needs_dynsym_entry();
1402 this->copied_symbol_dynobjs_
[csym
] = dynobj
;
1404 // We have now defined all aliases, but we have not entered them all
1405 // in the copied_symbol_dynobjs_ map.
1406 if (csym
->has_alias())
1411 sym
= this->weak_aliases_
[sym
];
1414 gold_assert(sym
->output_data() == posd
);
1416 sym
->set_is_copied_from_dynobj();
1417 this->copied_symbol_dynobjs_
[sym
] = dynobj
;
1422 // SYM is defined using a COPY reloc. Return the dynamic object where
1423 // the original definition was found.
1426 Symbol_table::get_copy_source(const Symbol
* sym
) const
1428 gold_assert(sym
->is_copied_from_dynobj());
1429 Copied_symbol_dynobjs::const_iterator p
=
1430 this->copied_symbol_dynobjs_
.find(sym
);
1431 gold_assert(p
!= this->copied_symbol_dynobjs_
.end());
1435 // Set the dynamic symbol indexes. INDEX is the index of the first
1436 // global dynamic symbol. Pointers to the symbols are stored into the
1437 // vector SYMS. The names are added to DYNPOOL. This returns an
1438 // updated dynamic symbol index.
1441 Symbol_table::set_dynsym_indexes(const Target
* target
,
1443 std::vector
<Symbol
*>* syms
,
1444 Stringpool
* dynpool
,
1447 for (Symbol_table_type::iterator p
= this->table_
.begin();
1448 p
!= this->table_
.end();
1451 Symbol
* sym
= p
->second
;
1453 // Note that SYM may already have a dynamic symbol index, since
1454 // some symbols appear more than once in the symbol table, with
1455 // and without a version.
1457 if (!sym
->should_add_dynsym_entry())
1458 sym
->set_dynsym_index(-1U);
1459 else if (!sym
->has_dynsym_index())
1461 sym
->set_dynsym_index(index
);
1463 syms
->push_back(sym
);
1464 dynpool
->add(sym
->name(), false, NULL
);
1466 // Record any version information.
1467 if (sym
->version() != NULL
)
1468 versions
->record_version(this, dynpool
, sym
);
1472 // Finish up the versions. In some cases this may add new dynamic
1474 index
= versions
->finalize(target
, this, index
, syms
);
1479 // Set the final values for all the symbols. The index of the first
1480 // global symbol in the output file is *PLOCAL_SYMCOUNT. Record the
1481 // file offset OFF. Add their names to POOL. Return the new file
1482 // offset. Update *PLOCAL_SYMCOUNT if necessary.
1485 Symbol_table::finalize(off_t off
, off_t dynoff
, size_t dyn_global_index
,
1486 size_t dyncount
, Stringpool
* pool
,
1487 unsigned int *plocal_symcount
)
1491 gold_assert(*plocal_symcount
!= 0);
1492 this->first_global_index_
= *plocal_symcount
;
1494 this->dynamic_offset_
= dynoff
;
1495 this->first_dynamic_global_index_
= dyn_global_index
;
1496 this->dynamic_count_
= dyncount
;
1498 if (parameters
->get_size() == 32)
1500 #if defined(HAVE_TARGET_32_BIG) || defined(HAVE_TARGET_32_LITTLE)
1501 ret
= this->sized_finalize
<32>(off
, pool
, plocal_symcount
);
1506 else if (parameters
->get_size() == 64)
1508 #if defined(HAVE_TARGET_64_BIG) || defined(HAVE_TARGET_64_LITTLE)
1509 ret
= this->sized_finalize
<64>(off
, pool
, plocal_symcount
);
1517 // Now that we have the final symbol table, we can reliably note
1518 // which symbols should get warnings.
1519 this->warnings_
.note_warnings(this);
1524 // SYM is going into the symbol table at *PINDEX. Add the name to
1525 // POOL, update *PINDEX and *POFF.
1529 Symbol_table::add_to_final_symtab(Symbol
* sym
, Stringpool
* pool
,
1530 unsigned int* pindex
, off_t
* poff
)
1532 sym
->set_symtab_index(*pindex
);
1533 pool
->add(sym
->name(), false, NULL
);
1535 *poff
+= elfcpp::Elf_sizes
<size
>::sym_size
;
1538 // Set the final value for all the symbols. This is called after
1539 // Layout::finalize, so all the output sections have their final
1544 Symbol_table::sized_finalize(off_t off
, Stringpool
* pool
,
1545 unsigned int* plocal_symcount
)
1547 off
= align_address(off
, size
>> 3);
1548 this->offset_
= off
;
1550 unsigned int index
= *plocal_symcount
;
1551 const unsigned int orig_index
= index
;
1553 // First do all the symbols which have been forced to be local, as
1554 // they must appear before all global symbols.
1555 for (Forced_locals::iterator p
= this->forced_locals_
.begin();
1556 p
!= this->forced_locals_
.end();
1560 gold_assert(sym
->is_forced_local());
1561 if (this->sized_finalize_symbol
<size
>(sym
))
1563 this->add_to_final_symtab
<size
>(sym
, pool
, &index
, &off
);
1568 // Now do all the remaining symbols.
1569 for (Symbol_table_type::iterator p
= this->table_
.begin();
1570 p
!= this->table_
.end();
1573 Symbol
* sym
= p
->second
;
1574 if (this->sized_finalize_symbol
<size
>(sym
))
1575 this->add_to_final_symtab
<size
>(sym
, pool
, &index
, &off
);
1578 this->output_count_
= index
- orig_index
;
1583 // Finalize the symbol SYM. This returns true if the symbol should be
1584 // added to the symbol table, false otherwise.
1588 Symbol_table::sized_finalize_symbol(Symbol
* unsized_sym
)
1590 Sized_symbol
<size
>* sym
= static_cast<Sized_symbol
<size
>*>(unsized_sym
);
1592 // The default version of a symbol may appear twice in the symbol
1593 // table. We only need to finalize it once.
1594 if (sym
->has_symtab_index())
1599 gold_assert(!sym
->has_symtab_index());
1600 sym
->set_symtab_index(-1U);
1601 gold_assert(sym
->dynsym_index() == -1U);
1605 typename Sized_symbol
<size
>::Value_type value
;
1607 switch (sym
->source())
1609 case Symbol::FROM_OBJECT
:
1611 unsigned int shndx
= sym
->shndx();
1613 // FIXME: We need some target specific support here.
1614 if (shndx
>= elfcpp::SHN_LORESERVE
1615 && shndx
!= elfcpp::SHN_ABS
)
1617 gold_error(_("%s: unsupported symbol section 0x%x"),
1618 sym
->demangled_name().c_str(), shndx
);
1619 shndx
= elfcpp::SHN_UNDEF
;
1622 Object
* symobj
= sym
->object();
1623 if (symobj
->is_dynamic())
1626 shndx
= elfcpp::SHN_UNDEF
;
1628 else if (shndx
== elfcpp::SHN_UNDEF
)
1630 else if (shndx
== elfcpp::SHN_ABS
)
1631 value
= sym
->value();
1634 Relobj
* relobj
= static_cast<Relobj
*>(symobj
);
1635 section_offset_type secoff
;
1636 Output_section
* os
= relobj
->output_section(shndx
, &secoff
);
1640 sym
->set_symtab_index(-1U);
1641 gold_assert(sym
->dynsym_index() == -1U);
1645 if (sym
->type() == elfcpp::STT_TLS
)
1646 value
= sym
->value() + os
->tls_offset() + secoff
;
1648 value
= sym
->value() + os
->address() + secoff
;
1653 case Symbol::IN_OUTPUT_DATA
:
1655 Output_data
* od
= sym
->output_data();
1656 value
= sym
->value() + od
->address();
1657 if (sym
->offset_is_from_end())
1658 value
+= od
->data_size();
1662 case Symbol::IN_OUTPUT_SEGMENT
:
1664 Output_segment
* os
= sym
->output_segment();
1665 value
= sym
->value() + os
->vaddr();
1666 switch (sym
->offset_base())
1668 case Symbol::SEGMENT_START
:
1670 case Symbol::SEGMENT_END
:
1671 value
+= os
->memsz();
1673 case Symbol::SEGMENT_BSS
:
1674 value
+= os
->filesz();
1682 case Symbol::CONSTANT
:
1683 value
= sym
->value();
1690 sym
->set_value(value
);
1692 if (parameters
->strip_all())
1694 sym
->set_symtab_index(-1U);
1701 // Write out the global symbols.
1704 Symbol_table::write_globals(const Input_objects
* input_objects
,
1705 const Stringpool
* sympool
,
1706 const Stringpool
* dynpool
, Output_file
* of
) const
1708 if (parameters
->get_size() == 32)
1710 if (parameters
->is_big_endian())
1712 #ifdef HAVE_TARGET_32_BIG
1713 this->sized_write_globals
<32, true>(input_objects
, sympool
,
1721 #ifdef HAVE_TARGET_32_LITTLE
1722 this->sized_write_globals
<32, false>(input_objects
, sympool
,
1729 else if (parameters
->get_size() == 64)
1731 if (parameters
->is_big_endian())
1733 #ifdef HAVE_TARGET_64_BIG
1734 this->sized_write_globals
<64, true>(input_objects
, sympool
,
1742 #ifdef HAVE_TARGET_64_LITTLE
1743 this->sized_write_globals
<64, false>(input_objects
, sympool
,
1754 // Write out the global symbols.
1756 template<int size
, bool big_endian
>
1758 Symbol_table::sized_write_globals(const Input_objects
* input_objects
,
1759 const Stringpool
* sympool
,
1760 const Stringpool
* dynpool
,
1761 Output_file
* of
) const
1763 const Target
* const target
= input_objects
->target();
1765 const int sym_size
= elfcpp::Elf_sizes
<size
>::sym_size
;
1767 const unsigned int output_count
= this->output_count_
;
1768 const section_size_type oview_size
= output_count
* sym_size
;
1769 const unsigned int first_global_index
= this->first_global_index_
;
1770 unsigned char* const psyms
= of
->get_output_view(this->offset_
, oview_size
);
1772 const unsigned int dynamic_count
= this->dynamic_count_
;
1773 const section_size_type dynamic_size
= dynamic_count
* sym_size
;
1774 const unsigned int first_dynamic_global_index
=
1775 this->first_dynamic_global_index_
;
1776 unsigned char* dynamic_view
;
1777 if (this->dynamic_offset_
== 0)
1778 dynamic_view
= NULL
;
1780 dynamic_view
= of
->get_output_view(this->dynamic_offset_
, dynamic_size
);
1782 for (Symbol_table_type::const_iterator p
= this->table_
.begin();
1783 p
!= this->table_
.end();
1786 Sized_symbol
<size
>* sym
= static_cast<Sized_symbol
<size
>*>(p
->second
);
1788 // Possibly warn about unresolved symbols in shared libraries.
1789 this->warn_about_undefined_dynobj_symbol(input_objects
, sym
);
1791 unsigned int sym_index
= sym
->symtab_index();
1792 unsigned int dynsym_index
;
1793 if (dynamic_view
== NULL
)
1796 dynsym_index
= sym
->dynsym_index();
1798 if (sym_index
== -1U && dynsym_index
== -1U)
1800 // This symbol is not included in the output file.
1805 typename
elfcpp::Elf_types
<32>::Elf_Addr value
= sym
->value();
1806 switch (sym
->source())
1808 case Symbol::FROM_OBJECT
:
1810 unsigned int in_shndx
= sym
->shndx();
1812 // FIXME: We need some target specific support here.
1813 if (in_shndx
>= elfcpp::SHN_LORESERVE
1814 && in_shndx
!= elfcpp::SHN_ABS
)
1816 gold_error(_("%s: unsupported symbol section 0x%x"),
1817 sym
->demangled_name().c_str(), in_shndx
);
1822 Object
* symobj
= sym
->object();
1823 if (symobj
->is_dynamic())
1825 if (sym
->needs_dynsym_value())
1826 value
= target
->dynsym_value(sym
);
1827 shndx
= elfcpp::SHN_UNDEF
;
1829 else if (in_shndx
== elfcpp::SHN_UNDEF
1830 || in_shndx
== elfcpp::SHN_ABS
)
1834 Relobj
* relobj
= static_cast<Relobj
*>(symobj
);
1835 section_offset_type secoff
;
1836 Output_section
* os
= relobj
->output_section(in_shndx
,
1838 gold_assert(os
!= NULL
);
1839 shndx
= os
->out_shndx();
1845 case Symbol::IN_OUTPUT_DATA
:
1846 shndx
= sym
->output_data()->out_shndx();
1849 case Symbol::IN_OUTPUT_SEGMENT
:
1850 shndx
= elfcpp::SHN_ABS
;
1853 case Symbol::CONSTANT
:
1854 shndx
= elfcpp::SHN_ABS
;
1861 if (sym_index
!= -1U)
1863 sym_index
-= first_global_index
;
1864 gold_assert(sym_index
< output_count
);
1865 unsigned char* ps
= psyms
+ (sym_index
* sym_size
);
1866 this->sized_write_symbol
SELECT_SIZE_ENDIAN_NAME(size
, big_endian
) (
1867 sym
, sym
->value(), shndx
, sympool
, ps
1868 SELECT_SIZE_ENDIAN(size
, big_endian
));
1871 if (dynsym_index
!= -1U)
1873 dynsym_index
-= first_dynamic_global_index
;
1874 gold_assert(dynsym_index
< dynamic_count
);
1875 unsigned char* pd
= dynamic_view
+ (dynsym_index
* sym_size
);
1876 this->sized_write_symbol
SELECT_SIZE_ENDIAN_NAME(size
, big_endian
) (
1877 sym
, value
, shndx
, dynpool
, pd
1878 SELECT_SIZE_ENDIAN(size
, big_endian
));
1882 of
->write_output_view(this->offset_
, oview_size
, psyms
);
1883 if (dynamic_view
!= NULL
)
1884 of
->write_output_view(this->dynamic_offset_
, dynamic_size
, dynamic_view
);
1887 // Write out the symbol SYM, in section SHNDX, to P. POOL is the
1888 // strtab holding the name.
1890 template<int size
, bool big_endian
>
1892 Symbol_table::sized_write_symbol(
1893 Sized_symbol
<size
>* sym
,
1894 typename
elfcpp::Elf_types
<size
>::Elf_Addr value
,
1896 const Stringpool
* pool
,
1898 ACCEPT_SIZE_ENDIAN
) const
1900 elfcpp::Sym_write
<size
, big_endian
> osym(p
);
1901 osym
.put_st_name(pool
->get_offset(sym
->name()));
1902 osym
.put_st_value(value
);
1903 osym
.put_st_size(sym
->symsize());
1904 // A version script may have overridden the default binding.
1905 if (sym
->is_forced_local())
1906 osym
.put_st_info(elfcpp::elf_st_info(elfcpp::STB_LOCAL
, sym
->type()));
1908 osym
.put_st_info(elfcpp::elf_st_info(sym
->binding(), sym
->type()));
1909 osym
.put_st_other(elfcpp::elf_st_other(sym
->visibility(), sym
->nonvis()));
1910 osym
.put_st_shndx(shndx
);
1913 // Check for unresolved symbols in shared libraries. This is
1914 // controlled by the --allow-shlib-undefined option.
1916 // We only warn about libraries for which we have seen all the
1917 // DT_NEEDED entries. We don't try to track down DT_NEEDED entries
1918 // which were not seen in this link. If we didn't see a DT_NEEDED
1919 // entry, we aren't going to be able to reliably report whether the
1920 // symbol is undefined.
1922 // We also don't warn about libraries found in the system library
1923 // directory (the directory were we find libc.so); we assume that
1924 // those libraries are OK. This heuristic avoids problems in
1925 // GNU/Linux, in which -ldl can have undefined references satisfied by
1929 Symbol_table::warn_about_undefined_dynobj_symbol(
1930 const Input_objects
* input_objects
,
1933 if (sym
->source() == Symbol::FROM_OBJECT
1934 && sym
->object()->is_dynamic()
1935 && sym
->shndx() == elfcpp::SHN_UNDEF
1936 && sym
->binding() != elfcpp::STB_WEAK
1937 && !parameters
->allow_shlib_undefined()
1938 && !input_objects
->target()->is_defined_by_abi(sym
)
1939 && !input_objects
->found_in_system_library_directory(sym
->object()))
1941 // A very ugly cast.
1942 Dynobj
* dynobj
= static_cast<Dynobj
*>(sym
->object());
1943 if (!dynobj
->has_unknown_needed_entries())
1944 gold_error(_("%s: undefined reference to '%s'"),
1945 sym
->object()->name().c_str(),
1946 sym
->demangled_name().c_str());
1950 // Write out a section symbol. Return the update offset.
1953 Symbol_table::write_section_symbol(const Output_section
*os
,
1957 if (parameters
->get_size() == 32)
1959 if (parameters
->is_big_endian())
1961 #ifdef HAVE_TARGET_32_BIG
1962 this->sized_write_section_symbol
<32, true>(os
, of
, offset
);
1969 #ifdef HAVE_TARGET_32_LITTLE
1970 this->sized_write_section_symbol
<32, false>(os
, of
, offset
);
1976 else if (parameters
->get_size() == 64)
1978 if (parameters
->is_big_endian())
1980 #ifdef HAVE_TARGET_64_BIG
1981 this->sized_write_section_symbol
<64, true>(os
, of
, offset
);
1988 #ifdef HAVE_TARGET_64_LITTLE
1989 this->sized_write_section_symbol
<64, false>(os
, of
, offset
);
1999 // Write out a section symbol, specialized for size and endianness.
2001 template<int size
, bool big_endian
>
2003 Symbol_table::sized_write_section_symbol(const Output_section
* os
,
2007 const int sym_size
= elfcpp::Elf_sizes
<size
>::sym_size
;
2009 unsigned char* pov
= of
->get_output_view(offset
, sym_size
);
2011 elfcpp::Sym_write
<size
, big_endian
> osym(pov
);
2012 osym
.put_st_name(0);
2013 osym
.put_st_value(os
->address());
2014 osym
.put_st_size(0);
2015 osym
.put_st_info(elfcpp::elf_st_info(elfcpp::STB_LOCAL
,
2016 elfcpp::STT_SECTION
));
2017 osym
.put_st_other(elfcpp::elf_st_other(elfcpp::STV_DEFAULT
, 0));
2018 osym
.put_st_shndx(os
->out_shndx());
2020 of
->write_output_view(offset
, sym_size
, pov
);
2023 // Print statistical information to stderr. This is used for --stats.
2026 Symbol_table::print_stats() const
2028 #if defined(HAVE_TR1_UNORDERED_MAP) || defined(HAVE_EXT_HASH_MAP)
2029 fprintf(stderr
, _("%s: symbol table entries: %zu; buckets: %zu\n"),
2030 program_name
, this->table_
.size(), this->table_
.bucket_count());
2032 fprintf(stderr
, _("%s: symbol table entries: %zu\n"),
2033 program_name
, this->table_
.size());
2035 this->namepool_
.print_stats("symbol table stringpool");
2038 // We check for ODR violations by looking for symbols with the same
2039 // name for which the debugging information reports that they were
2040 // defined in different source locations. When comparing the source
2041 // location, we consider instances with the same base filename and
2042 // line number to be the same. This is because different object
2043 // files/shared libraries can include the same header file using
2044 // different paths, and we don't want to report an ODR violation in
2047 // This struct is used to compare line information, as returned by
2048 // Dwarf_line_info::one_addr2line. It implements a < comparison
2049 // operator used with std::set.
2051 struct Odr_violation_compare
2054 operator()(const std::string
& s1
, const std::string
& s2
) const
2056 std::string::size_type pos1
= s1
.rfind('/');
2057 std::string::size_type pos2
= s2
.rfind('/');
2058 if (pos1
== std::string::npos
2059 || pos2
== std::string::npos
)
2061 return s1
.compare(pos1
, std::string::npos
,
2062 s2
, pos2
, std::string::npos
) < 0;
2066 // Check candidate_odr_violations_ to find symbols with the same name
2067 // but apparently different definitions (different source-file/line-no).
2070 Symbol_table::detect_odr_violations(const Task
* task
,
2071 const char* output_file_name
) const
2073 for (Odr_map::const_iterator it
= candidate_odr_violations_
.begin();
2074 it
!= candidate_odr_violations_
.end();
2077 const char* symbol_name
= it
->first
;
2078 // We use a sorted set so the output is deterministic.
2079 std::set
<std::string
, Odr_violation_compare
> line_nums
;
2081 for (Unordered_set
<Symbol_location
, Symbol_location_hash
>::const_iterator
2082 locs
= it
->second
.begin();
2083 locs
!= it
->second
.end();
2086 // We need to lock the object in order to read it. This
2087 // means that we have to run in a singleton Task. If we
2088 // want to run this in a general Task for better
2089 // performance, we will need one Task for object, plus
2090 // appropriate locking to ensure that we don't conflict with
2091 // other uses of the object.
2092 Task_lock_obj
<Object
> tl(task
, locs
->object
);
2093 std::string lineno
= Dwarf_line_info::one_addr2line(
2094 locs
->object
, locs
->shndx
, locs
->offset
);
2095 if (!lineno
.empty())
2096 line_nums
.insert(lineno
);
2099 if (line_nums
.size() > 1)
2101 gold_warning(_("while linking %s: symbol '%s' defined in multiple "
2102 "places (possible ODR violation):"),
2103 output_file_name
, demangle(symbol_name
).c_str());
2104 for (std::set
<std::string
>::const_iterator it2
= line_nums
.begin();
2105 it2
!= line_nums
.end();
2107 fprintf(stderr
, " %s\n", it2
->c_str());
2112 // Warnings functions.
2114 // Add a new warning.
2117 Warnings::add_warning(Symbol_table
* symtab
, const char* name
, Object
* obj
,
2118 const std::string
& warning
)
2120 name
= symtab
->canonicalize_name(name
);
2121 this->warnings_
[name
].set(obj
, warning
);
2124 // Look through the warnings and mark the symbols for which we should
2125 // warn. This is called during Layout::finalize when we know the
2126 // sources for all the symbols.
2129 Warnings::note_warnings(Symbol_table
* symtab
)
2131 for (Warning_table::iterator p
= this->warnings_
.begin();
2132 p
!= this->warnings_
.end();
2135 Symbol
* sym
= symtab
->lookup(p
->first
, NULL
);
2137 && sym
->source() == Symbol::FROM_OBJECT
2138 && sym
->object() == p
->second
.object
)
2139 sym
->set_has_warning();
2143 // Issue a warning. This is called when we see a relocation against a
2144 // symbol for which has a warning.
2146 template<int size
, bool big_endian
>
2148 Warnings::issue_warning(const Symbol
* sym
,
2149 const Relocate_info
<size
, big_endian
>* relinfo
,
2150 size_t relnum
, off_t reloffset
) const
2152 gold_assert(sym
->has_warning());
2153 Warning_table::const_iterator p
= this->warnings_
.find(sym
->name());
2154 gold_assert(p
!= this->warnings_
.end());
2155 gold_warning_at_location(relinfo
, relnum
, reloffset
,
2156 "%s", p
->second
.text
.c_str());
2159 // Instantiate the templates we need. We could use the configure
2160 // script to restrict this to only the ones needed for implemented
2163 #if defined(HAVE_TARGET_32_LITTLE) || defined(HAVE_TARGET_32_BIG)
2166 Sized_symbol
<32>::allocate_common(Output_data
*, Value_type
);
2169 #if defined(HAVE_TARGET_64_LITTLE) || defined(HAVE_TARGET_64_BIG)
2172 Sized_symbol
<64>::allocate_common(Output_data
*, Value_type
);
2175 #ifdef HAVE_TARGET_32_LITTLE
2178 Symbol_table::add_from_relobj
<32, false>(
2179 Sized_relobj
<32, false>* relobj
,
2180 const unsigned char* syms
,
2182 const char* sym_names
,
2183 size_t sym_name_size
,
2184 Sized_relobj
<32, true>::Symbols
* sympointers
);
2187 #ifdef HAVE_TARGET_32_BIG
2190 Symbol_table::add_from_relobj
<32, true>(
2191 Sized_relobj
<32, true>* relobj
,
2192 const unsigned char* syms
,
2194 const char* sym_names
,
2195 size_t sym_name_size
,
2196 Sized_relobj
<32, false>::Symbols
* sympointers
);
2199 #ifdef HAVE_TARGET_64_LITTLE
2202 Symbol_table::add_from_relobj
<64, false>(
2203 Sized_relobj
<64, false>* relobj
,
2204 const unsigned char* syms
,
2206 const char* sym_names
,
2207 size_t sym_name_size
,
2208 Sized_relobj
<64, true>::Symbols
* sympointers
);
2211 #ifdef HAVE_TARGET_64_BIG
2214 Symbol_table::add_from_relobj
<64, true>(
2215 Sized_relobj
<64, true>* relobj
,
2216 const unsigned char* syms
,
2218 const char* sym_names
,
2219 size_t sym_name_size
,
2220 Sized_relobj
<64, false>::Symbols
* sympointers
);
2223 #ifdef HAVE_TARGET_32_LITTLE
2226 Symbol_table::add_from_dynobj
<32, false>(
2227 Sized_dynobj
<32, false>* dynobj
,
2228 const unsigned char* syms
,
2230 const char* sym_names
,
2231 size_t sym_name_size
,
2232 const unsigned char* versym
,
2234 const std::vector
<const char*>* version_map
);
2237 #ifdef HAVE_TARGET_32_BIG
2240 Symbol_table::add_from_dynobj
<32, true>(
2241 Sized_dynobj
<32, true>* dynobj
,
2242 const unsigned char* syms
,
2244 const char* sym_names
,
2245 size_t sym_name_size
,
2246 const unsigned char* versym
,
2248 const std::vector
<const char*>* version_map
);
2251 #ifdef HAVE_TARGET_64_LITTLE
2254 Symbol_table::add_from_dynobj
<64, false>(
2255 Sized_dynobj
<64, false>* dynobj
,
2256 const unsigned char* syms
,
2258 const char* sym_names
,
2259 size_t sym_name_size
,
2260 const unsigned char* versym
,
2262 const std::vector
<const char*>* version_map
);
2265 #ifdef HAVE_TARGET_64_BIG
2268 Symbol_table::add_from_dynobj
<64, true>(
2269 Sized_dynobj
<64, true>* dynobj
,
2270 const unsigned char* syms
,
2272 const char* sym_names
,
2273 size_t sym_name_size
,
2274 const unsigned char* versym
,
2276 const std::vector
<const char*>* version_map
);
2279 #if defined(HAVE_TARGET_32_LITTLE) || defined(HAVE_TARGET_32_BIG)
2282 Symbol_table::define_with_copy_reloc
<32>(
2283 const Target
* target
,
2284 Sized_symbol
<32>* sym
,
2286 elfcpp::Elf_types
<32>::Elf_Addr value
);
2289 #if defined(HAVE_TARGET_64_LITTLE) || defined(HAVE_TARGET_64_BIG)
2292 Symbol_table::define_with_copy_reloc
<64>(
2293 const Target
* target
,
2294 Sized_symbol
<64>* sym
,
2296 elfcpp::Elf_types
<64>::Elf_Addr value
);
2299 #ifdef HAVE_TARGET_32_LITTLE
2302 Warnings::issue_warning
<32, false>(const Symbol
* sym
,
2303 const Relocate_info
<32, false>* relinfo
,
2304 size_t relnum
, off_t reloffset
) const;
2307 #ifdef HAVE_TARGET_32_BIG
2310 Warnings::issue_warning
<32, true>(const Symbol
* sym
,
2311 const Relocate_info
<32, true>* relinfo
,
2312 size_t relnum
, off_t reloffset
) const;
2315 #ifdef HAVE_TARGET_64_LITTLE
2318 Warnings::issue_warning
<64, false>(const Symbol
* sym
,
2319 const Relocate_info
<64, false>* relinfo
,
2320 size_t relnum
, off_t reloffset
) const;
2323 #ifdef HAVE_TARGET_64_BIG
2326 Warnings::issue_warning
<64, true>(const Symbol
* sym
,
2327 const Relocate_info
<64, true>* relinfo
,
2328 size_t relnum
, off_t reloffset
) const;
2331 } // End namespace gold.