1 // symtab.cc -- the gold symbol table
13 #include "workqueue.h"
21 // Initialize fields in Symbol. This initializes everything except u_
25 Symbol::init_fields(const char* name
, const char* version
,
26 elfcpp::STT type
, elfcpp::STB binding
,
27 elfcpp::STV visibility
, unsigned char nonvis
)
30 this->version_
= version
;
31 this->symtab_index_
= 0;
32 this->dynsym_index_
= 0;
33 this->got_offset_
= 0;
34 this->plt_offset_
= 0;
36 this->binding_
= binding
;
37 this->visibility_
= visibility
;
38 this->nonvis_
= nonvis
;
39 this->is_target_special_
= false;
40 this->is_def_
= false;
41 this->is_forwarder_
= false;
42 this->needs_dynsym_entry_
= false;
43 this->in_reg_
= false;
44 this->in_dyn_
= false;
45 this->has_got_offset_
= false;
46 this->has_plt_offset_
= false;
47 this->has_warning_
= false;
50 // Initialize the fields in the base class Symbol for SYM in OBJECT.
52 template<int size
, bool big_endian
>
54 Symbol::init_base(const char* name
, const char* version
, Object
* object
,
55 const elfcpp::Sym
<size
, big_endian
>& sym
)
57 this->init_fields(name
, version
, sym
.get_st_type(), sym
.get_st_bind(),
58 sym
.get_st_visibility(), sym
.get_st_nonvis());
59 this->u_
.from_object
.object
= object
;
60 // FIXME: Handle SHN_XINDEX.
61 this->u_
.from_object
.shndx
= sym
.get_st_shndx();
62 this->source_
= FROM_OBJECT
;
63 this->in_reg_
= !object
->is_dynamic();
64 this->in_dyn_
= object
->is_dynamic();
67 // Initialize the fields in the base class Symbol for a symbol defined
71 Symbol::init_base(const char* name
, Output_data
* od
, elfcpp::STT type
,
72 elfcpp::STB binding
, elfcpp::STV visibility
,
73 unsigned char nonvis
, bool offset_is_from_end
)
75 this->init_fields(name
, NULL
, type
, binding
, visibility
, nonvis
);
76 this->u_
.in_output_data
.output_data
= od
;
77 this->u_
.in_output_data
.offset_is_from_end
= offset_is_from_end
;
78 this->source_
= IN_OUTPUT_DATA
;
82 // Initialize the fields in the base class Symbol for a symbol defined
83 // in an Output_segment.
86 Symbol::init_base(const char* name
, Output_segment
* os
, elfcpp::STT type
,
87 elfcpp::STB binding
, elfcpp::STV visibility
,
88 unsigned char nonvis
, Segment_offset_base offset_base
)
90 this->init_fields(name
, NULL
, type
, binding
, visibility
, nonvis
);
91 this->u_
.in_output_segment
.output_segment
= os
;
92 this->u_
.in_output_segment
.offset_base
= offset_base
;
93 this->source_
= IN_OUTPUT_SEGMENT
;
97 // Initialize the fields in the base class Symbol for a symbol defined
101 Symbol::init_base(const char* name
, elfcpp::STT type
,
102 elfcpp::STB binding
, elfcpp::STV visibility
,
103 unsigned char nonvis
)
105 this->init_fields(name
, NULL
, type
, binding
, visibility
, nonvis
);
106 this->source_
= CONSTANT
;
107 this->in_reg_
= true;
110 // Initialize the fields in Sized_symbol for SYM in OBJECT.
113 template<bool big_endian
>
115 Sized_symbol
<size
>::init(const char* name
, const char* version
, Object
* object
,
116 const elfcpp::Sym
<size
, big_endian
>& sym
)
118 this->init_base(name
, version
, object
, sym
);
119 this->value_
= sym
.get_st_value();
120 this->symsize_
= sym
.get_st_size();
123 // Initialize the fields in Sized_symbol for a symbol defined in an
128 Sized_symbol
<size
>::init(const char* name
, Output_data
* od
,
129 Value_type value
, Size_type symsize
,
130 elfcpp::STT type
, elfcpp::STB binding
,
131 elfcpp::STV visibility
, unsigned char nonvis
,
132 bool offset_is_from_end
)
134 this->init_base(name
, od
, type
, binding
, visibility
, nonvis
,
136 this->value_
= value
;
137 this->symsize_
= symsize
;
140 // Initialize the fields in Sized_symbol for a symbol defined in an
145 Sized_symbol
<size
>::init(const char* name
, Output_segment
* os
,
146 Value_type value
, Size_type symsize
,
147 elfcpp::STT type
, elfcpp::STB binding
,
148 elfcpp::STV visibility
, unsigned char nonvis
,
149 Segment_offset_base offset_base
)
151 this->init_base(name
, os
, type
, binding
, visibility
, nonvis
, offset_base
);
152 this->value_
= value
;
153 this->symsize_
= symsize
;
156 // Initialize the fields in Sized_symbol for a symbol defined as a
161 Sized_symbol
<size
>::init(const char* name
, Value_type value
, Size_type symsize
,
162 elfcpp::STT type
, elfcpp::STB binding
,
163 elfcpp::STV visibility
, unsigned char nonvis
)
165 this->init_base(name
, type
, binding
, visibility
, nonvis
);
166 this->value_
= value
;
167 this->symsize_
= symsize
;
170 // Class Symbol_table.
172 Symbol_table::Symbol_table()
173 : size_(0), saw_undefined_(0), offset_(0), table_(), namepool_(),
174 forwarders_(), commons_(), warnings_()
178 Symbol_table::~Symbol_table()
182 // The hash function. The key is always canonicalized, so we use a
183 // simple combination of the pointers.
186 Symbol_table::Symbol_table_hash::operator()(const Symbol_table_key
& key
) const
188 return key
.first
^ key
.second
;
191 // The symbol table key equality function. This is only called with
192 // canonicalized name and version strings, so we can use pointer
196 Symbol_table::Symbol_table_eq::operator()(const Symbol_table_key
& k1
,
197 const Symbol_table_key
& k2
) const
199 return k1
.first
== k2
.first
&& k1
.second
== k2
.second
;
202 // Make TO a symbol which forwards to FROM.
205 Symbol_table::make_forwarder(Symbol
* from
, Symbol
* to
)
207 gold_assert(from
!= to
);
208 gold_assert(!from
->is_forwarder() && !to
->is_forwarder());
209 this->forwarders_
[from
] = to
;
210 from
->set_forwarder();
213 // Resolve the forwards from FROM, returning the real symbol.
216 Symbol_table::resolve_forwards(const Symbol
* from
) const
218 gold_assert(from
->is_forwarder());
219 Unordered_map
<const Symbol
*, Symbol
*>::const_iterator p
=
220 this->forwarders_
.find(from
);
221 gold_assert(p
!= this->forwarders_
.end());
225 // Look up a symbol by name.
228 Symbol_table::lookup(const char* name
, const char* version
) const
230 Stringpool::Key name_key
;
231 name
= this->namepool_
.find(name
, &name_key
);
235 Stringpool::Key version_key
= 0;
238 version
= this->namepool_
.find(version
, &version_key
);
243 Symbol_table_key
key(name_key
, version_key
);
244 Symbol_table::Symbol_table_type::const_iterator p
= this->table_
.find(key
);
245 if (p
== this->table_
.end())
250 // Resolve a Symbol with another Symbol. This is only used in the
251 // unusual case where there are references to both an unversioned
252 // symbol and a symbol with a version, and we then discover that that
253 // version is the default version. Because this is unusual, we do
254 // this the slow way, by converting back to an ELF symbol.
256 template<int size
, bool big_endian
>
258 Symbol_table::resolve(Sized_symbol
<size
>* to
, const Sized_symbol
<size
>* from
,
259 const char* version ACCEPT_SIZE_ENDIAN
)
261 unsigned char buf
[elfcpp::Elf_sizes
<size
>::sym_size
];
262 elfcpp::Sym_write
<size
, big_endian
> esym(buf
);
263 // We don't bother to set the st_name field.
264 esym
.put_st_value(from
->value());
265 esym
.put_st_size(from
->symsize());
266 esym
.put_st_info(from
->binding(), from
->type());
267 esym
.put_st_other(from
->visibility(), from
->nonvis());
268 esym
.put_st_shndx(from
->shndx());
269 Symbol_table::resolve(to
, esym
.sym(), from
->object(), version
);
272 // Add one symbol from OBJECT to the symbol table. NAME is symbol
273 // name and VERSION is the version; both are canonicalized. DEF is
274 // whether this is the default version.
276 // If DEF is true, then this is the definition of a default version of
277 // a symbol. That means that any lookup of NAME/NULL and any lookup
278 // of NAME/VERSION should always return the same symbol. This is
279 // obvious for references, but in particular we want to do this for
280 // definitions: overriding NAME/NULL should also override
281 // NAME/VERSION. If we don't do that, it would be very hard to
282 // override functions in a shared library which uses versioning.
284 // We implement this by simply making both entries in the hash table
285 // point to the same Symbol structure. That is easy enough if this is
286 // the first time we see NAME/NULL or NAME/VERSION, but it is possible
287 // that we have seen both already, in which case they will both have
288 // independent entries in the symbol table. We can't simply change
289 // the symbol table entry, because we have pointers to the entries
290 // attached to the object files. So we mark the entry attached to the
291 // object file as a forwarder, and record it in the forwarders_ map.
292 // Note that entries in the hash table will never be marked as
295 template<int size
, bool big_endian
>
297 Symbol_table::add_from_object(Object
* object
,
299 Stringpool::Key name_key
,
301 Stringpool::Key version_key
,
303 const elfcpp::Sym
<size
, big_endian
>& sym
)
305 Symbol
* const snull
= NULL
;
306 std::pair
<typename
Symbol_table_type::iterator
, bool> ins
=
307 this->table_
.insert(std::make_pair(std::make_pair(name_key
, version_key
),
310 std::pair
<typename
Symbol_table_type::iterator
, bool> insdef
=
311 std::make_pair(this->table_
.end(), false);
314 const Stringpool::Key vnull_key
= 0;
315 insdef
= this->table_
.insert(std::make_pair(std::make_pair(name_key
,
320 // ins.first: an iterator, which is a pointer to a pair.
321 // ins.first->first: the key (a pair of name and version).
322 // ins.first->second: the value (Symbol*).
323 // ins.second: true if new entry was inserted, false if not.
325 Sized_symbol
<size
>* ret
;
330 // We already have an entry for NAME/VERSION.
331 ret
= this->get_sized_symbol
SELECT_SIZE_NAME(size
) (ins
.first
->second
333 gold_assert(ret
!= NULL
);
335 was_undefined
= ret
->is_undefined();
336 was_common
= ret
->is_common();
338 Symbol_table::resolve(ret
, sym
, object
, version
);
344 // This is the first time we have seen NAME/NULL. Make
345 // NAME/NULL point to NAME/VERSION.
346 insdef
.first
->second
= ret
;
348 else if (insdef
.first
->second
!= ret
)
350 // This is the unfortunate case where we already have
351 // entries for both NAME/VERSION and NAME/NULL.
352 const Sized_symbol
<size
>* sym2
;
353 sym2
= this->get_sized_symbol
SELECT_SIZE_NAME(size
) (
356 Symbol_table::resolve
SELECT_SIZE_ENDIAN_NAME(size
, big_endian
) (
357 ret
, sym2
, version
SELECT_SIZE_ENDIAN(size
, big_endian
));
358 this->make_forwarder(insdef
.first
->second
, ret
);
359 insdef
.first
->second
= ret
;
365 // This is the first time we have seen NAME/VERSION.
366 gold_assert(ins
.first
->second
== NULL
);
368 was_undefined
= false;
371 if (def
&& !insdef
.second
)
373 // We already have an entry for NAME/NULL. If we override
374 // it, then change it to NAME/VERSION.
375 ret
= this->get_sized_symbol
SELECT_SIZE_NAME(size
) (
378 Symbol_table::resolve(ret
, sym
, object
, version
);
379 ins
.first
->second
= ret
;
383 Sized_target
<size
, big_endian
>* target
=
384 object
->sized_target
SELECT_SIZE_ENDIAN_NAME(size
, big_endian
) (
385 SELECT_SIZE_ENDIAN_ONLY(size
, big_endian
));
386 if (!target
->has_make_symbol())
387 ret
= new Sized_symbol
<size
>();
390 ret
= target
->make_symbol();
393 // This means that we don't want a symbol table
396 this->table_
.erase(ins
.first
);
399 this->table_
.erase(insdef
.first
);
400 // Inserting insdef invalidated ins.
401 this->table_
.erase(std::make_pair(name_key
,
408 ret
->init(name
, version
, object
, sym
);
410 ins
.first
->second
= ret
;
413 // This is the first time we have seen NAME/NULL. Point
414 // it at the new entry for NAME/VERSION.
415 gold_assert(insdef
.second
);
416 insdef
.first
->second
= ret
;
421 // Record every time we see a new undefined symbol, to speed up
423 if (!was_undefined
&& ret
->is_undefined())
424 ++this->saw_undefined_
;
426 // Keep track of common symbols, to speed up common symbol
428 if (!was_common
&& ret
->is_common())
429 this->commons_
.push_back(ret
);
434 // Add all the symbols in a relocatable object to the hash table.
436 template<int size
, bool big_endian
>
438 Symbol_table::add_from_relobj(
439 Sized_relobj
<size
, big_endian
>* relobj
,
440 const unsigned char* syms
,
442 const char* sym_names
,
443 size_t sym_name_size
,
444 Symbol
** sympointers
)
446 // We take the size from the first object we see.
447 if (this->get_size() == 0)
448 this->set_size(size
);
450 if (size
!= this->get_size() || size
!= relobj
->target()->get_size())
452 fprintf(stderr
, _("%s: %s: mixing 32-bit and 64-bit ELF objects\n"),
453 program_name
, relobj
->name().c_str());
457 const int sym_size
= elfcpp::Elf_sizes
<size
>::sym_size
;
459 const unsigned char* p
= syms
;
460 for (size_t i
= 0; i
< count
; ++i
, p
+= sym_size
)
462 elfcpp::Sym
<size
, big_endian
> sym(p
);
463 elfcpp::Sym
<size
, big_endian
>* psym
= &sym
;
465 unsigned int st_name
= psym
->get_st_name();
466 if (st_name
>= sym_name_size
)
469 _("%s: %s: bad global symbol name offset %u at %lu\n"),
470 program_name
, relobj
->name().c_str(), st_name
,
471 static_cast<unsigned long>(i
));
475 const char* name
= sym_names
+ st_name
;
477 // A symbol defined in a section which we are not including must
478 // be treated as an undefined symbol.
479 unsigned char symbuf
[sym_size
];
480 elfcpp::Sym
<size
, big_endian
> sym2(symbuf
);
481 unsigned int st_shndx
= psym
->get_st_shndx();
482 if (st_shndx
!= elfcpp::SHN_UNDEF
483 && st_shndx
< elfcpp::SHN_LORESERVE
484 && !relobj
->is_section_included(st_shndx
))
486 memcpy(symbuf
, p
, sym_size
);
487 elfcpp::Sym_write
<size
, big_endian
> sw(symbuf
);
488 sw
.put_st_shndx(elfcpp::SHN_UNDEF
);
492 // In an object file, an '@' in the name separates the symbol
493 // name from the version name. If there are two '@' characters,
494 // this is the default version.
495 const char* ver
= strchr(name
, '@');
500 Stringpool::Key name_key
;
501 name
= this->namepool_
.add(name
, &name_key
);
502 res
= this->add_from_object(relobj
, name
, name_key
, NULL
, 0,
507 Stringpool::Key name_key
;
508 name
= this->namepool_
.add(name
, ver
- name
, &name_key
);
518 Stringpool::Key ver_key
;
519 ver
= this->namepool_
.add(ver
, &ver_key
);
521 res
= this->add_from_object(relobj
, name
, name_key
, ver
, ver_key
,
525 *sympointers
++ = res
;
529 // Add all the symbols in a dynamic object to the hash table.
531 template<int size
, bool big_endian
>
533 Symbol_table::add_from_dynobj(
534 Sized_dynobj
<size
, big_endian
>* dynobj
,
535 const unsigned char* syms
,
537 const char* sym_names
,
538 size_t sym_name_size
,
539 const unsigned char* versym
,
541 const std::vector
<const char*>* version_map
)
543 // We take the size from the first object we see.
544 if (this->get_size() == 0)
545 this->set_size(size
);
547 if (size
!= this->get_size() || size
!= dynobj
->target()->get_size())
549 fprintf(stderr
, _("%s: %s: mixing 32-bit and 64-bit ELF objects\n"),
550 program_name
, dynobj
->name().c_str());
554 if (versym
!= NULL
&& versym_size
/ 2 < count
)
556 fprintf(stderr
, _("%s: %s: too few symbol versions\n"),
557 program_name
, dynobj
->name().c_str());
561 const int sym_size
= elfcpp::Elf_sizes
<size
>::sym_size
;
563 const unsigned char* p
= syms
;
564 const unsigned char* vs
= versym
;
565 for (size_t i
= 0; i
< count
; ++i
, p
+= sym_size
, vs
+= 2)
567 elfcpp::Sym
<size
, big_endian
> sym(p
);
569 // Ignore symbols with local binding.
570 if (sym
.get_st_bind() == elfcpp::STB_LOCAL
)
573 unsigned int st_name
= sym
.get_st_name();
574 if (st_name
>= sym_name_size
)
576 fprintf(stderr
, _("%s: %s: bad symbol name offset %u at %lu\n"),
577 program_name
, dynobj
->name().c_str(), st_name
,
578 static_cast<unsigned long>(i
));
582 const char* name
= sym_names
+ st_name
;
586 Stringpool::Key name_key
;
587 name
= this->namepool_
.add(name
, &name_key
);
588 this->add_from_object(dynobj
, name
, name_key
, NULL
, 0,
593 // Read the version information.
595 unsigned int v
= elfcpp::Swap
<16, big_endian
>::readval(vs
);
597 bool hidden
= (v
& elfcpp::VERSYM_HIDDEN
) != 0;
598 v
&= elfcpp::VERSYM_VERSION
;
600 if (v
== static_cast<unsigned int>(elfcpp::VER_NDX_LOCAL
))
602 // This symbol should not be visible outside the object.
606 // At this point we are definitely going to add this symbol.
607 Stringpool::Key name_key
;
608 name
= this->namepool_
.add(name
, &name_key
);
610 if (v
== static_cast<unsigned int>(elfcpp::VER_NDX_GLOBAL
))
612 // This symbol does not have a version.
613 this->add_from_object(dynobj
, name
, name_key
, NULL
, 0, false, sym
);
617 if (v
>= version_map
->size())
620 _("%s: %s: versym for symbol %zu out of range: %u\n"),
621 program_name
, dynobj
->name().c_str(), i
, v
);
625 const char* version
= (*version_map
)[v
];
628 fprintf(stderr
, _("%s: %s: versym for symbol %zu has no name: %u\n"),
629 program_name
, dynobj
->name().c_str(), i
, v
);
633 Stringpool::Key version_key
;
634 version
= this->namepool_
.add(version
, &version_key
);
636 // If this is an absolute symbol, and the version name and
637 // symbol name are the same, then this is the version definition
638 // symbol. These symbols exist to support using -u to pull in
639 // particular versions. We do not want to record a version for
641 if (sym
.get_st_shndx() == elfcpp::SHN_ABS
&& name_key
== version_key
)
643 this->add_from_object(dynobj
, name
, name_key
, NULL
, 0, false, sym
);
647 const bool def
= !hidden
&& sym
.get_st_shndx() != elfcpp::SHN_UNDEF
;
649 this->add_from_object(dynobj
, name
, name_key
, version
, version_key
,
654 // Create and return a specially defined symbol. If ONLY_IF_REF is
655 // true, then only create the symbol if there is a reference to it.
657 template<int size
, bool big_endian
>
659 Symbol_table::define_special_symbol(const Target
* target
, const char* name
,
660 const char* version
, bool only_if_ref
663 gold_assert(this->size_
== size
);
666 Sized_symbol
<size
>* sym
;
670 oldsym
= this->lookup(name
, version
);
671 if (oldsym
== NULL
|| !oldsym
->is_undefined())
675 // Canonicalize NAME and VERSION.
676 name
= oldsym
->name();
677 version
= oldsym
->version();
681 // Canonicalize NAME and VERSION.
682 Stringpool::Key name_key
;
683 name
= this->namepool_
.add(name
, &name_key
);
685 Stringpool::Key version_key
= 0;
687 version
= this->namepool_
.add(version
, &version_key
);
689 Symbol
* const snull
= NULL
;
690 std::pair
<typename
Symbol_table_type::iterator
, bool> ins
=
691 this->table_
.insert(std::make_pair(std::make_pair(name_key
,
697 // We already have a symbol table entry for NAME/VERSION.
698 oldsym
= ins
.first
->second
;
699 gold_assert(oldsym
!= NULL
);
704 // We haven't seen this symbol before.
705 gold_assert(ins
.first
->second
== NULL
);
707 if (!target
->has_make_symbol())
708 sym
= new Sized_symbol
<size
>();
711 gold_assert(target
->get_size() == size
);
712 gold_assert(target
->is_big_endian() ? big_endian
: !big_endian
);
713 typedef Sized_target
<size
, big_endian
> My_target
;
714 const My_target
* sized_target
=
715 static_cast<const My_target
*>(target
);
716 sym
= sized_target
->make_symbol();
721 ins
.first
->second
= sym
;
728 gold_assert(sym
== NULL
);
730 sym
= this->get_sized_symbol
SELECT_SIZE_NAME(size
) (oldsym
732 gold_assert(sym
->source() == Symbol::FROM_OBJECT
);
733 const int old_shndx
= sym
->shndx();
734 if (old_shndx
!= elfcpp::SHN_UNDEF
735 && old_shndx
!= elfcpp::SHN_COMMON
736 && !sym
->object()->is_dynamic())
738 fprintf(stderr
, "%s: linker defined: multiple definition of %s\n",
740 // FIXME: Report old location. Record that we have seen an
745 // Our new definition is going to override the old reference.
751 // Define a symbol based on an Output_data.
754 Symbol_table::define_in_output_data(const Target
* target
, const char* name
,
755 const char* version
, Output_data
* od
,
756 uint64_t value
, uint64_t symsize
,
757 elfcpp::STT type
, elfcpp::STB binding
,
758 elfcpp::STV visibility
,
759 unsigned char nonvis
,
760 bool offset_is_from_end
,
763 gold_assert(target
->get_size() == this->size_
);
764 if (this->size_
== 32)
765 return this->do_define_in_output_data
<32>(target
, name
, version
, od
, value
,
766 symsize
, type
, binding
,
768 offset_is_from_end
, only_if_ref
);
769 else if (this->size_
== 64)
770 return this->do_define_in_output_data
<64>(target
, name
, version
, od
, value
,
771 symsize
, type
, binding
,
773 offset_is_from_end
, only_if_ref
);
778 // Define a symbol in an Output_data, sized version.
782 Symbol_table::do_define_in_output_data(
783 const Target
* target
,
787 typename
elfcpp::Elf_types
<size
>::Elf_Addr value
,
788 typename
elfcpp::Elf_types
<size
>::Elf_WXword symsize
,
791 elfcpp::STV visibility
,
792 unsigned char nonvis
,
793 bool offset_is_from_end
,
796 Sized_symbol
<size
>* sym
;
798 if (target
->is_big_endian())
799 sym
= this->define_special_symbol
SELECT_SIZE_ENDIAN_NAME(size
, true) (
800 target
, name
, version
, only_if_ref
801 SELECT_SIZE_ENDIAN(size
, true));
803 sym
= this->define_special_symbol
SELECT_SIZE_ENDIAN_NAME(size
, false) (
804 target
, name
, version
, only_if_ref
805 SELECT_SIZE_ENDIAN(size
, false));
810 sym
->init(name
, od
, value
, symsize
, type
, binding
, visibility
, nonvis
,
816 // Define a symbol based on an Output_segment.
819 Symbol_table::define_in_output_segment(const Target
* target
, const char* name
,
820 const char* version
, Output_segment
* os
,
821 uint64_t value
, uint64_t symsize
,
822 elfcpp::STT type
, elfcpp::STB binding
,
823 elfcpp::STV visibility
,
824 unsigned char nonvis
,
825 Symbol::Segment_offset_base offset_base
,
828 gold_assert(target
->get_size() == this->size_
);
829 if (this->size_
== 32)
830 return this->do_define_in_output_segment
<32>(target
, name
, version
, os
,
831 value
, symsize
, type
, binding
,
833 offset_base
, only_if_ref
);
834 else if (this->size_
== 64)
835 return this->do_define_in_output_segment
<64>(target
, name
, version
, os
,
836 value
, symsize
, type
, binding
,
838 offset_base
, only_if_ref
);
843 // Define a symbol in an Output_segment, sized version.
847 Symbol_table::do_define_in_output_segment(
848 const Target
* target
,
852 typename
elfcpp::Elf_types
<size
>::Elf_Addr value
,
853 typename
elfcpp::Elf_types
<size
>::Elf_WXword symsize
,
856 elfcpp::STV visibility
,
857 unsigned char nonvis
,
858 Symbol::Segment_offset_base offset_base
,
861 Sized_symbol
<size
>* sym
;
863 if (target
->is_big_endian())
864 sym
= this->define_special_symbol
SELECT_SIZE_ENDIAN_NAME(size
, true) (
865 target
, name
, version
, only_if_ref
866 SELECT_SIZE_ENDIAN(size
, true));
868 sym
= this->define_special_symbol
SELECT_SIZE_ENDIAN_NAME(size
, false) (
869 target
, name
, version
, only_if_ref
870 SELECT_SIZE_ENDIAN(size
, false));
875 sym
->init(name
, os
, value
, symsize
, type
, binding
, visibility
, nonvis
,
881 // Define a special symbol with a constant value. It is a multiple
882 // definition error if this symbol is already defined.
885 Symbol_table::define_as_constant(const Target
* target
, const char* name
,
886 const char* version
, uint64_t value
,
887 uint64_t symsize
, elfcpp::STT type
,
888 elfcpp::STB binding
, elfcpp::STV visibility
,
889 unsigned char nonvis
, bool only_if_ref
)
891 gold_assert(target
->get_size() == this->size_
);
892 if (this->size_
== 32)
893 return this->do_define_as_constant
<32>(target
, name
, version
, value
,
894 symsize
, type
, binding
, visibility
,
895 nonvis
, only_if_ref
);
896 else if (this->size_
== 64)
897 return this->do_define_as_constant
<64>(target
, name
, version
, value
,
898 symsize
, type
, binding
, visibility
,
899 nonvis
, only_if_ref
);
904 // Define a symbol as a constant, sized version.
908 Symbol_table::do_define_as_constant(
909 const Target
* target
,
912 typename
elfcpp::Elf_types
<size
>::Elf_Addr value
,
913 typename
elfcpp::Elf_types
<size
>::Elf_WXword symsize
,
916 elfcpp::STV visibility
,
917 unsigned char nonvis
,
920 Sized_symbol
<size
>* sym
;
922 if (target
->is_big_endian())
923 sym
= this->define_special_symbol
SELECT_SIZE_ENDIAN_NAME(size
, true) (
924 target
, name
, version
, only_if_ref
925 SELECT_SIZE_ENDIAN(size
, true));
927 sym
= this->define_special_symbol
SELECT_SIZE_ENDIAN_NAME(size
, false) (
928 target
, name
, version
, only_if_ref
929 SELECT_SIZE_ENDIAN(size
, false));
934 sym
->init(name
, value
, symsize
, type
, binding
, visibility
, nonvis
);
939 // Define a set of symbols in output sections.
942 Symbol_table::define_symbols(const Layout
* layout
, const Target
* target
,
943 int count
, const Define_symbol_in_section
* p
)
945 for (int i
= 0; i
< count
; ++i
, ++p
)
947 Output_section
* os
= layout
->find_output_section(p
->output_section
);
949 this->define_in_output_data(target
, p
->name
, NULL
, os
, p
->value
,
950 p
->size
, p
->type
, p
->binding
,
951 p
->visibility
, p
->nonvis
,
952 p
->offset_is_from_end
, p
->only_if_ref
);
954 this->define_as_constant(target
, p
->name
, NULL
, 0, p
->size
, p
->type
,
955 p
->binding
, p
->visibility
, p
->nonvis
,
960 // Define a set of symbols in output segments.
963 Symbol_table::define_symbols(const Layout
* layout
, const Target
* target
,
964 int count
, const Define_symbol_in_segment
* p
)
966 for (int i
= 0; i
< count
; ++i
, ++p
)
968 Output_segment
* os
= layout
->find_output_segment(p
->segment_type
,
969 p
->segment_flags_set
,
970 p
->segment_flags_clear
);
972 this->define_in_output_segment(target
, p
->name
, NULL
, os
, p
->value
,
973 p
->size
, p
->type
, p
->binding
,
974 p
->visibility
, p
->nonvis
,
975 p
->offset_base
, p
->only_if_ref
);
977 this->define_as_constant(target
, p
->name
, NULL
, 0, p
->size
, p
->type
,
978 p
->binding
, p
->visibility
, p
->nonvis
,
983 // Set the dynamic symbol indexes. INDEX is the index of the first
984 // global dynamic symbol. Pointers to the symbols are stored into the
985 // vector SYMS. The names are added to DYNPOOL. This returns an
986 // updated dynamic symbol index.
989 Symbol_table::set_dynsym_indexes(const General_options
* options
,
990 const Target
* target
,
992 std::vector
<Symbol
*>* syms
,
996 for (Symbol_table_type::iterator p
= this->table_
.begin();
997 p
!= this->table_
.end();
1000 Symbol
* sym
= p
->second
;
1002 // Note that SYM may already have a dynamic symbol index, since
1003 // some symbols appear more than once in the symbol table, with
1004 // and without a version.
1006 if (!sym
->needs_dynsym_entry()
1007 && (!options
->export_dynamic()
1009 || !sym
->is_externally_visible()))
1010 sym
->set_dynsym_index(-1U);
1011 else if (!sym
->has_dynsym_index())
1013 sym
->set_dynsym_index(index
);
1015 syms
->push_back(sym
);
1016 dynpool
->add(sym
->name(), NULL
);
1018 // Record any version information.
1019 if (sym
->version() != NULL
)
1020 versions
->record_version(options
, dynpool
, sym
);
1024 // Finish up the versions. In some cases this may add new dynamic
1026 index
= versions
->finalize(target
, this, index
, syms
);
1031 // Set the final values for all the symbols. The index of the first
1032 // global symbol in the output file is INDEX. Record the file offset
1033 // OFF. Add their names to POOL. Return the new file offset.
1036 Symbol_table::finalize(unsigned int index
, off_t off
, off_t dynoff
,
1037 size_t dyn_global_index
, size_t dyncount
,
1042 gold_assert(index
!= 0);
1043 this->first_global_index_
= index
;
1045 this->dynamic_offset_
= dynoff
;
1046 this->first_dynamic_global_index_
= dyn_global_index
;
1047 this->dynamic_count_
= dyncount
;
1049 if (this->size_
== 32)
1050 ret
= this->sized_finalize
<32>(index
, off
, pool
);
1051 else if (this->size_
== 64)
1052 ret
= this->sized_finalize
<64>(index
, off
, pool
);
1056 // Now that we have the final symbol table, we can reliably note
1057 // which symbols should get warnings.
1058 this->warnings_
.note_warnings(this);
1063 // Set the final value for all the symbols. This is called after
1064 // Layout::finalize, so all the output sections have their final
1069 Symbol_table::sized_finalize(unsigned index
, off_t off
, Stringpool
* pool
)
1071 off
= align_address(off
, size
>> 3);
1072 this->offset_
= off
;
1074 size_t orig_index
= index
;
1076 const int sym_size
= elfcpp::Elf_sizes
<size
>::sym_size
;
1077 for (Symbol_table_type::iterator p
= this->table_
.begin();
1078 p
!= this->table_
.end();
1081 Sized_symbol
<size
>* sym
= static_cast<Sized_symbol
<size
>*>(p
->second
);
1083 // FIXME: Here we need to decide which symbols should go into
1084 // the output file, based on --strip.
1086 // The default version of a symbol may appear twice in the
1087 // symbol table. We only need to finalize it once.
1088 if (sym
->has_symtab_index())
1093 gold_assert(!sym
->has_symtab_index());
1094 sym
->set_symtab_index(-1U);
1095 gold_assert(sym
->dynsym_index() == -1U);
1099 typename Sized_symbol
<size
>::Value_type value
;
1101 switch (sym
->source())
1103 case Symbol::FROM_OBJECT
:
1105 unsigned int shndx
= sym
->shndx();
1107 // FIXME: We need some target specific support here.
1108 if (shndx
>= elfcpp::SHN_LORESERVE
1109 && shndx
!= elfcpp::SHN_ABS
)
1111 fprintf(stderr
, _("%s: %s: unsupported symbol section 0x%x\n"),
1112 program_name
, sym
->name(), shndx
);
1116 Object
* symobj
= sym
->object();
1117 if (symobj
->is_dynamic())
1120 shndx
= elfcpp::SHN_UNDEF
;
1122 else if (shndx
== elfcpp::SHN_UNDEF
)
1124 else if (shndx
== elfcpp::SHN_ABS
)
1125 value
= sym
->value();
1128 Relobj
* relobj
= static_cast<Relobj
*>(symobj
);
1130 Output_section
* os
= relobj
->output_section(shndx
, &secoff
);
1134 sym
->set_symtab_index(-1U);
1135 gold_assert(sym
->dynsym_index() == -1U);
1139 value
= sym
->value() + os
->address() + secoff
;
1144 case Symbol::IN_OUTPUT_DATA
:
1146 Output_data
* od
= sym
->output_data();
1147 value
= sym
->value() + od
->address();
1148 if (sym
->offset_is_from_end())
1149 value
+= od
->data_size();
1153 case Symbol::IN_OUTPUT_SEGMENT
:
1155 Output_segment
* os
= sym
->output_segment();
1156 value
= sym
->value() + os
->vaddr();
1157 switch (sym
->offset_base())
1159 case Symbol::SEGMENT_START
:
1161 case Symbol::SEGMENT_END
:
1162 value
+= os
->memsz();
1164 case Symbol::SEGMENT_BSS
:
1165 value
+= os
->filesz();
1173 case Symbol::CONSTANT
:
1174 value
= sym
->value();
1181 sym
->set_value(value
);
1182 sym
->set_symtab_index(index
);
1183 pool
->add(sym
->name(), NULL
);
1188 this->output_count_
= index
- orig_index
;
1193 // Write out the global symbols.
1196 Symbol_table::write_globals(const Target
* target
, const Stringpool
* sympool
,
1197 const Stringpool
* dynpool
, Output_file
* of
) const
1199 if (this->size_
== 32)
1201 if (target
->is_big_endian())
1202 this->sized_write_globals
<32, true>(target
, sympool
, dynpool
, of
);
1204 this->sized_write_globals
<32, false>(target
, sympool
, dynpool
, of
);
1206 else if (this->size_
== 64)
1208 if (target
->is_big_endian())
1209 this->sized_write_globals
<64, true>(target
, sympool
, dynpool
, of
);
1211 this->sized_write_globals
<64, false>(target
, sympool
, dynpool
, of
);
1217 // Write out the global symbols.
1219 template<int size
, bool big_endian
>
1221 Symbol_table::sized_write_globals(const Target
*,
1222 const Stringpool
* sympool
,
1223 const Stringpool
* dynpool
,
1224 Output_file
* of
) const
1226 const int sym_size
= elfcpp::Elf_sizes
<size
>::sym_size
;
1227 unsigned int index
= this->first_global_index_
;
1228 const off_t oview_size
= this->output_count_
* sym_size
;
1229 unsigned char* const psyms
= of
->get_output_view(this->offset_
, oview_size
);
1231 unsigned int dynamic_count
= this->dynamic_count_
;
1232 off_t dynamic_size
= dynamic_count
* sym_size
;
1233 unsigned int first_dynamic_global_index
= this->first_dynamic_global_index_
;
1234 unsigned char* dynamic_view
;
1235 if (this->dynamic_offset_
== 0)
1236 dynamic_view
= NULL
;
1238 dynamic_view
= of
->get_output_view(this->dynamic_offset_
, dynamic_size
);
1240 unsigned char* ps
= psyms
;
1241 for (Symbol_table_type::const_iterator p
= this->table_
.begin();
1242 p
!= this->table_
.end();
1245 Sized_symbol
<size
>* sym
= static_cast<Sized_symbol
<size
>*>(p
->second
);
1247 unsigned int sym_index
= sym
->symtab_index();
1248 unsigned int dynsym_index
;
1249 if (dynamic_view
== NULL
)
1252 dynsym_index
= sym
->dynsym_index();
1254 if (sym_index
== -1U && dynsym_index
== -1U)
1256 // This symbol is not included in the output file.
1260 if (sym_index
== index
)
1262 else if (sym_index
!= -1U)
1264 // We have already seen this symbol, because it has a
1266 gold_assert(sym_index
< index
);
1267 if (dynsym_index
== -1U)
1273 switch (sym
->source())
1275 case Symbol::FROM_OBJECT
:
1277 unsigned int in_shndx
= sym
->shndx();
1279 // FIXME: We need some target specific support here.
1280 if (in_shndx
>= elfcpp::SHN_LORESERVE
1281 && in_shndx
!= elfcpp::SHN_ABS
)
1283 fprintf(stderr
, _("%s: %s: unsupported symbol section 0x%x\n"),
1284 program_name
, sym
->name(), in_shndx
);
1288 Object
* symobj
= sym
->object();
1289 if (symobj
->is_dynamic())
1292 shndx
= elfcpp::SHN_UNDEF
;
1294 else if (in_shndx
== elfcpp::SHN_UNDEF
1295 || in_shndx
== elfcpp::SHN_ABS
)
1299 Relobj
* relobj
= static_cast<Relobj
*>(symobj
);
1301 Output_section
* os
= relobj
->output_section(in_shndx
, &secoff
);
1302 gold_assert(os
!= NULL
);
1303 shndx
= os
->out_shndx();
1308 case Symbol::IN_OUTPUT_DATA
:
1309 shndx
= sym
->output_data()->out_shndx();
1312 case Symbol::IN_OUTPUT_SEGMENT
:
1313 shndx
= elfcpp::SHN_ABS
;
1316 case Symbol::CONSTANT
:
1317 shndx
= elfcpp::SHN_ABS
;
1324 if (sym_index
!= -1U)
1326 this->sized_write_symbol
SELECT_SIZE_ENDIAN_NAME(size
, big_endian
) (
1327 sym
, shndx
, sympool
, ps
1328 SELECT_SIZE_ENDIAN(size
, big_endian
));
1332 if (dynsym_index
!= -1U)
1334 dynsym_index
-= first_dynamic_global_index
;
1335 gold_assert(dynsym_index
< dynamic_count
);
1336 unsigned char* pd
= dynamic_view
+ (dynsym_index
* sym_size
);
1337 this->sized_write_symbol
SELECT_SIZE_ENDIAN_NAME(size
, big_endian
) (
1338 sym
, shndx
, dynpool
, pd
1339 SELECT_SIZE_ENDIAN(size
, big_endian
));
1343 gold_assert(ps
- psyms
== oview_size
);
1345 of
->write_output_view(this->offset_
, oview_size
, psyms
);
1346 if (dynamic_view
!= NULL
)
1347 of
->write_output_view(this->dynamic_offset_
, dynamic_size
, dynamic_view
);
1350 // Write out the symbol SYM, in section SHNDX, to P. POOL is the
1351 // strtab holding the name.
1353 template<int size
, bool big_endian
>
1355 Symbol_table::sized_write_symbol(Sized_symbol
<size
>* sym
,
1357 const Stringpool
* pool
,
1359 ACCEPT_SIZE_ENDIAN
) const
1361 elfcpp::Sym_write
<size
, big_endian
> osym(p
);
1362 osym
.put_st_name(pool
->get_offset(sym
->name()));
1363 osym
.put_st_value(sym
->value());
1364 osym
.put_st_size(sym
->symsize());
1365 osym
.put_st_info(elfcpp::elf_st_info(sym
->binding(), sym
->type()));
1366 osym
.put_st_other(elfcpp::elf_st_other(sym
->visibility(), sym
->nonvis()));
1367 osym
.put_st_shndx(shndx
);
1370 // Write out a section symbol. Return the update offset.
1373 Symbol_table::write_section_symbol(const Target
* target
,
1374 const Output_section
*os
,
1378 if (this->size_
== 32)
1380 if (target
->is_big_endian())
1381 this->sized_write_section_symbol
<32, true>(os
, of
, offset
);
1383 this->sized_write_section_symbol
<32, false>(os
, of
, offset
);
1385 else if (this->size_
== 64)
1387 if (target
->is_big_endian())
1388 this->sized_write_section_symbol
<64, true>(os
, of
, offset
);
1390 this->sized_write_section_symbol
<64, false>(os
, of
, offset
);
1396 // Write out a section symbol, specialized for size and endianness.
1398 template<int size
, bool big_endian
>
1400 Symbol_table::sized_write_section_symbol(const Output_section
* os
,
1404 const int sym_size
= elfcpp::Elf_sizes
<size
>::sym_size
;
1406 unsigned char* pov
= of
->get_output_view(offset
, sym_size
);
1408 elfcpp::Sym_write
<size
, big_endian
> osym(pov
);
1409 osym
.put_st_name(0);
1410 osym
.put_st_value(os
->address());
1411 osym
.put_st_size(0);
1412 osym
.put_st_info(elfcpp::elf_st_info(elfcpp::STB_LOCAL
,
1413 elfcpp::STT_SECTION
));
1414 osym
.put_st_other(elfcpp::elf_st_other(elfcpp::STV_DEFAULT
, 0));
1415 osym
.put_st_shndx(os
->out_shndx());
1417 of
->write_output_view(offset
, sym_size
, pov
);
1420 // Warnings functions.
1422 // Add a new warning.
1425 Warnings::add_warning(Symbol_table
* symtab
, const char* name
, Object
* obj
,
1428 name
= symtab
->canonicalize_name(name
);
1429 this->warnings_
[name
].set(obj
, shndx
);
1432 // Look through the warnings and mark the symbols for which we should
1433 // warn. This is called during Layout::finalize when we know the
1434 // sources for all the symbols.
1437 Warnings::note_warnings(Symbol_table
* symtab
)
1439 for (Warning_table::iterator p
= this->warnings_
.begin();
1440 p
!= this->warnings_
.end();
1443 Symbol
* sym
= symtab
->lookup(p
->first
, NULL
);
1445 && sym
->source() == Symbol::FROM_OBJECT
1446 && sym
->object() == p
->second
.object
)
1448 sym
->set_has_warning();
1450 // Read the section contents to get the warning text. It
1451 // would be nicer if we only did this if we have to actually
1452 // issue a warning. Unfortunately, warnings are issued as
1453 // we relocate sections. That means that we can not lock
1454 // the object then, as we might try to issue the same
1455 // warning multiple times simultaneously.
1457 Task_locker_obj
<Object
> tl(*p
->second
.object
);
1458 const unsigned char* c
;
1460 c
= p
->second
.object
->section_contents(p
->second
.shndx
, &len
);
1461 p
->second
.set_text(reinterpret_cast<const char*>(c
), len
);
1467 // Issue a warning. This is called when we see a relocation against a
1468 // symbol for which has a warning.
1471 Warnings::issue_warning(const Symbol
* sym
, const std::string
& location
) const
1473 gold_assert(sym
->has_warning());
1474 Warning_table::const_iterator p
= this->warnings_
.find(sym
->name());
1475 gold_assert(p
!= this->warnings_
.end());
1476 fprintf(stderr
, _("%s: %s: warning: %s\n"), program_name
, location
.c_str(),
1477 p
->second
.text
.c_str());
1480 // Instantiate the templates we need. We could use the configure
1481 // script to restrict this to only the ones needed for implemented
1486 Symbol_table::add_from_relobj
<32, true>(
1487 Sized_relobj
<32, true>* relobj
,
1488 const unsigned char* syms
,
1490 const char* sym_names
,
1491 size_t sym_name_size
,
1492 Symbol
** sympointers
);
1496 Symbol_table::add_from_relobj
<32, false>(
1497 Sized_relobj
<32, false>* relobj
,
1498 const unsigned char* syms
,
1500 const char* sym_names
,
1501 size_t sym_name_size
,
1502 Symbol
** sympointers
);
1506 Symbol_table::add_from_relobj
<64, true>(
1507 Sized_relobj
<64, true>* relobj
,
1508 const unsigned char* syms
,
1510 const char* sym_names
,
1511 size_t sym_name_size
,
1512 Symbol
** sympointers
);
1516 Symbol_table::add_from_relobj
<64, false>(
1517 Sized_relobj
<64, false>* relobj
,
1518 const unsigned char* syms
,
1520 const char* sym_names
,
1521 size_t sym_name_size
,
1522 Symbol
** sympointers
);
1526 Symbol_table::add_from_dynobj
<32, true>(
1527 Sized_dynobj
<32, true>* dynobj
,
1528 const unsigned char* syms
,
1530 const char* sym_names
,
1531 size_t sym_name_size
,
1532 const unsigned char* versym
,
1534 const std::vector
<const char*>* version_map
);
1538 Symbol_table::add_from_dynobj
<32, false>(
1539 Sized_dynobj
<32, false>* dynobj
,
1540 const unsigned char* syms
,
1542 const char* sym_names
,
1543 size_t sym_name_size
,
1544 const unsigned char* versym
,
1546 const std::vector
<const char*>* version_map
);
1550 Symbol_table::add_from_dynobj
<64, true>(
1551 Sized_dynobj
<64, true>* dynobj
,
1552 const unsigned char* syms
,
1554 const char* sym_names
,
1555 size_t sym_name_size
,
1556 const unsigned char* versym
,
1558 const std::vector
<const char*>* version_map
);
1562 Symbol_table::add_from_dynobj
<64, false>(
1563 Sized_dynobj
<64, false>* dynobj
,
1564 const unsigned char* syms
,
1566 const char* sym_names
,
1567 size_t sym_name_size
,
1568 const unsigned char* versym
,
1570 const std::vector
<const char*>* version_map
);
1572 } // End namespace gold.