1 // symtab.h -- the gold symbol table -*- C++ -*-
3 // Copyright 2006, 2007, 2008, 2009, 2010, 2011 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.
34 #include "parameters.h"
35 #include "stringpool.h"
44 template<int size, bool big_endian>
45 class Sized_relobj_file;
46 template<int size, bool big_endian>
47 class Sized_pluginobj;
49 template<int size, bool big_endian>
51 template<int size, bool big_endian>
54 class Version_script_info;
60 class Output_symtab_xindex;
61 class Garbage_collection;
64 // The base class of an entry in the symbol table. The symbol table
65 // can have a lot of entries, so we don't want this class to big.
66 // Size dependent fields can be found in the template class
67 // Sized_symbol. Targets may support their own derived classes.
72 // Because we want the class to be small, we don't use any virtual
73 // functions. But because symbols can be defined in different
74 // places, we need to classify them. This enum is the different
75 // sources of symbols we support.
78 // Symbol defined in a relocatable or dynamic input file--this is
79 // the most common case.
81 // Symbol defined in an Output_data, a special section created by
84 // Symbol defined in an Output_segment, with no associated
87 // Symbol value is constant.
89 // Symbol is undefined.
93 // When the source is IN_OUTPUT_SEGMENT, we need to describe what
95 enum Segment_offset_base
97 // From the start of the segment.
99 // From the end of the segment.
101 // From the filesz of the segment--i.e., after the loaded bytes
102 // but before the bytes which are allocated but zeroed.
106 // Return the symbol name.
109 { return this->name_; }
111 // Return the (ANSI) demangled version of the name, if
112 // parameters.demangle() is true. Otherwise, return the name. This
113 // is intended to be used only for logging errors, so it's not
116 demangled_name() const;
118 // Return the symbol version. This will return NULL for an
119 // unversioned symbol.
122 { return this->version_; }
124 // Return whether this version is the default for this symbol name
125 // (eg, "foo@@V2" is a default version; "foo@V1" is not). Only
126 // meaningful for versioned symbols.
130 gold_assert(this->version_ != NULL);
131 return this->is_def_;
134 // Set that this version is the default for this symbol name.
137 { this->is_def_ = true; }
139 // Return the symbol's name as name@version (or name@@version).
141 versioned_name() const;
143 // Return the symbol source.
146 { return this->source_; }
148 // Return the object with which this symbol is associated.
152 gold_assert(this->source_ == FROM_OBJECT);
153 return this->u_.from_object.object;
156 // Return the index of the section in the input relocatable or
157 // dynamic object file.
159 shndx(bool* is_ordinary) const
161 gold_assert(this->source_ == FROM_OBJECT);
162 *is_ordinary = this->is_ordinary_shndx_;
163 return this->u_.from_object.shndx;
166 // Return the output data section with which this symbol is
167 // associated, if the symbol was specially defined with respect to
168 // an output data section.
172 gold_assert(this->source_ == IN_OUTPUT_DATA);
173 return this->u_.in_output_data.output_data;
176 // If this symbol was defined with respect to an output data
177 // section, return whether the value is an offset from end.
179 offset_is_from_end() const
181 gold_assert(this->source_ == IN_OUTPUT_DATA);
182 return this->u_.in_output_data.offset_is_from_end;
185 // Return the output segment with which this symbol is associated,
186 // if the symbol was specially defined with respect to an output
189 output_segment() const
191 gold_assert(this->source_ == IN_OUTPUT_SEGMENT);
192 return this->u_.in_output_segment.output_segment;
195 // If this symbol was defined with respect to an output segment,
196 // return the offset base.
200 gold_assert(this->source_ == IN_OUTPUT_SEGMENT);
201 return this->u_.in_output_segment.offset_base;
204 // Return the symbol binding.
207 { return this->binding_; }
209 // Return the symbol type.
212 { return this->type_; }
214 // Return true for function symbol.
218 return (this->type_ == elfcpp::STT_FUNC
219 || this->type_ == elfcpp::STT_GNU_IFUNC);
222 // Return the symbol visibility.
225 { return this->visibility_; }
227 // Set the visibility.
229 set_visibility(elfcpp::STV visibility)
230 { this->visibility_ = visibility; }
232 // Override symbol visibility.
234 override_visibility(elfcpp::STV);
236 // Set whether the symbol was originally a weak undef or a regular undef
237 // when resolved by a dynamic def.
239 set_undef_binding(elfcpp::STB bind)
241 if (!this->undef_binding_set_ || this->undef_binding_weak_)
243 this->undef_binding_weak_ = bind == elfcpp::STB_WEAK;
244 this->undef_binding_set_ = true;
248 // Return TRUE if a weak undef was resolved by a dynamic def.
250 is_undef_binding_weak() const
251 { return this->undef_binding_weak_; }
253 // Return the non-visibility part of the st_other field.
256 { return this->nonvis_; }
258 // Return whether this symbol is a forwarder. This will never be
259 // true of a symbol found in the hash table, but may be true of
260 // symbol pointers attached to object files.
263 { return this->is_forwarder_; }
265 // Mark this symbol as a forwarder.
268 { this->is_forwarder_ = true; }
270 // Return whether this symbol has an alias in the weak aliases table
274 { return this->has_alias_; }
276 // Mark this symbol as having an alias.
279 { this->has_alias_ = true; }
281 // Return whether this symbol needs an entry in the dynamic symbol
284 needs_dynsym_entry() const
286 return (this->needs_dynsym_entry_
289 && this->is_externally_visible()));
292 // Mark this symbol as needing an entry in the dynamic symbol table.
294 set_needs_dynsym_entry()
295 { this->needs_dynsym_entry_ = true; }
297 // Return whether this symbol should be added to the dynamic symbol
300 should_add_dynsym_entry(Symbol_table*) const;
302 // Return whether this symbol has been seen in a regular object.
305 { return this->in_reg_; }
307 // Mark this symbol as having been seen in a regular object.
310 { this->in_reg_ = true; }
312 // Return whether this symbol has been seen in a dynamic object.
315 { return this->in_dyn_; }
317 // Mark this symbol as having been seen in a dynamic object.
320 { this->in_dyn_ = true; }
322 // Return whether this symbol has been seen in a real ELF object.
323 // (IN_REG will return TRUE if the symbol has been seen in either
324 // a real ELF object or an object claimed by a plugin.)
327 { return this->in_real_elf_; }
329 // Mark this symbol as having been seen in a real ELF object.
332 { this->in_real_elf_ = true; }
334 // Return whether this symbol was defined in a section that was
335 // discarded from the link. This is used to control some error
338 is_defined_in_discarded_section() const
339 { return this->is_defined_in_discarded_section_; }
341 // Mark this symbol as having been defined in a discarded section.
343 set_is_defined_in_discarded_section()
344 { this->is_defined_in_discarded_section_ = true; }
346 // Return the index of this symbol in the output file symbol table.
347 // A value of -1U means that this symbol is not going into the
348 // output file. This starts out as zero, and is set to a non-zero
349 // value by Symbol_table::finalize. It is an error to ask for the
350 // symbol table index before it has been set.
354 gold_assert(this->symtab_index_ != 0);
355 return this->symtab_index_;
358 // Set the index of the symbol in the output file symbol table.
360 set_symtab_index(unsigned int index)
362 gold_assert(index != 0);
363 this->symtab_index_ = index;
366 // Return whether this symbol already has an index in the output
367 // file symbol table.
369 has_symtab_index() const
370 { return this->symtab_index_ != 0; }
372 // Return the index of this symbol in the dynamic symbol table. A
373 // value of -1U means that this symbol is not going into the dynamic
374 // symbol table. This starts out as zero, and is set to a non-zero
375 // during Layout::finalize. It is an error to ask for the dynamic
376 // symbol table index before it has been set.
380 gold_assert(this->dynsym_index_ != 0);
381 return this->dynsym_index_;
384 // Set the index of the symbol in the dynamic symbol table.
386 set_dynsym_index(unsigned int index)
388 gold_assert(index != 0);
389 this->dynsym_index_ = index;
392 // Return whether this symbol already has an index in the dynamic
395 has_dynsym_index() const
396 { return this->dynsym_index_ != 0; }
398 // Return whether this symbol has an entry in the GOT section.
399 // For a TLS symbol, this GOT entry will hold its tp-relative offset.
401 has_got_offset(unsigned int got_type) const
402 { return this->got_offsets_.get_offset(got_type) != -1U; }
404 // Return the offset into the GOT section of this symbol.
406 got_offset(unsigned int got_type) const
408 unsigned int got_offset = this->got_offsets_.get_offset(got_type);
409 gold_assert(got_offset != -1U);
413 // Set the GOT offset of this symbol.
415 set_got_offset(unsigned int got_type, unsigned int got_offset)
416 { this->got_offsets_.set_offset(got_type, got_offset); }
418 // Return the GOT offset list.
419 const Got_offset_list*
420 got_offset_list() const
421 { return this->got_offsets_.get_list(); }
423 // Return whether this symbol has an entry in the PLT section.
425 has_plt_offset() const
426 { return this->plt_offset_ != -1U; }
428 // Return the offset into the PLT section of this symbol.
432 gold_assert(this->has_plt_offset());
433 return this->plt_offset_;
436 // Set the PLT offset of this symbol.
438 set_plt_offset(unsigned int plt_offset)
440 gold_assert(plt_offset != -1U);
441 this->plt_offset_ = plt_offset;
444 // Return whether this dynamic symbol needs a special value in the
445 // dynamic symbol table.
447 needs_dynsym_value() const
448 { return this->needs_dynsym_value_; }
450 // Set that this dynamic symbol needs a special value in the dynamic
453 set_needs_dynsym_value()
455 gold_assert(this->object()->is_dynamic());
456 this->needs_dynsym_value_ = true;
459 // Return true if the final value of this symbol is known at link
462 final_value_is_known() const;
464 // Return true if SHNDX represents a common symbol. This depends on
467 is_common_shndx(unsigned int shndx);
469 // Return whether this is a defined symbol (not undefined or
475 if (this->source_ != FROM_OBJECT)
476 return this->source_ != IS_UNDEFINED;
477 unsigned int shndx = this->shndx(&is_ordinary);
479 ? shndx != elfcpp::SHN_UNDEF
480 : !Symbol::is_common_shndx(shndx));
483 // Return true if this symbol is from a dynamic object.
485 is_from_dynobj() const
487 return this->source_ == FROM_OBJECT && this->object()->is_dynamic();
490 // Return whether this is a placeholder symbol from a plugin object.
492 is_placeholder() const
494 return this->source_ == FROM_OBJECT && this->object()->pluginobj() != NULL;
497 // Return whether this is an undefined symbol.
502 return ((this->source_ == FROM_OBJECT
503 && this->shndx(&is_ordinary) == elfcpp::SHN_UNDEF
505 || this->source_ == IS_UNDEFINED);
508 // Return whether this is a weak undefined symbol.
510 is_weak_undefined() const
511 { return this->is_undefined() && this->binding() == elfcpp::STB_WEAK; }
513 // Return whether this is an absolute symbol.
518 return ((this->source_ == FROM_OBJECT
519 && this->shndx(&is_ordinary) == elfcpp::SHN_ABS
521 || this->source_ == IS_CONSTANT);
524 // Return whether this is a common symbol.
528 if (this->source_ != FROM_OBJECT)
530 if (this->type_ == elfcpp::STT_COMMON)
533 unsigned int shndx = this->shndx(&is_ordinary);
534 return !is_ordinary && Symbol::is_common_shndx(shndx);
537 // Return whether this symbol can be seen outside this object.
539 is_externally_visible() const
541 return (this->visibility_ == elfcpp::STV_DEFAULT
542 || this->visibility_ == elfcpp::STV_PROTECTED);
545 // Return true if this symbol can be preempted by a definition in
546 // another link unit.
548 is_preemptible() const
550 // It doesn't make sense to ask whether a symbol defined in
551 // another object is preemptible.
552 gold_assert(!this->is_from_dynobj());
554 // It doesn't make sense to ask whether an undefined symbol
556 gold_assert(!this->is_undefined());
558 // If a symbol does not have default visibility, it can not be
559 // seen outside this link unit and therefore is not preemptible.
560 if (this->visibility_ != elfcpp::STV_DEFAULT)
563 // If this symbol has been forced to be a local symbol by a
564 // version script, then it is not visible outside this link unit
565 // and is not preemptible.
566 if (this->is_forced_local_)
569 // If we are not producing a shared library, then nothing is
571 if (!parameters->options().shared())
574 // If the user used -Bsymbolic, then nothing is preemptible.
575 if (parameters->options().Bsymbolic())
578 // If the user used -Bsymbolic-functions, then functions are not
579 // preemptible. We explicitly check for not being STT_OBJECT,
580 // rather than for being STT_FUNC, because that is what the GNU
582 if (this->type() != elfcpp::STT_OBJECT
583 && parameters->options().Bsymbolic_functions())
586 // Otherwise the symbol is preemptible.
590 // Return true if this symbol is a function that needs a PLT entry.
592 needs_plt_entry() const
594 // An undefined symbol from an executable does not need a PLT entry.
595 if (this->is_undefined() && !parameters->options().shared())
598 // An STT_GNU_IFUNC symbol always needs a PLT entry, even when
599 // doing a static link.
600 if (this->type() == elfcpp::STT_GNU_IFUNC)
603 // We only need a PLT entry for a function.
604 if (!this->is_func())
607 // If we're doing a static link or a -pie link, we don't create
609 if (parameters->doing_static_link()
610 || parameters->options().pie())
613 // We need a PLT entry if the function is defined in a dynamic
614 // object, or is undefined when building a shared object, or if it
615 // is subject to pre-emption.
616 return (this->is_from_dynobj()
617 || this->is_undefined()
618 || this->is_preemptible());
621 // When determining whether a reference to a symbol needs a dynamic
622 // relocation, we need to know several things about the reference.
623 // These flags may be or'ed together. 0 means that the symbol
624 // isn't referenced at all.
627 // A reference to the symbol's absolute address. This includes
628 // references that cause an absolute address to be stored in the GOT.
630 // A reference that calculates the offset of the symbol from some
631 // anchor point, such as the PC or GOT.
633 // A TLS-related reference.
635 // A reference that can always be treated as a function call.
639 // Given a direct absolute or pc-relative static relocation against
640 // the global symbol, this function returns whether a dynamic relocation
644 needs_dynamic_reloc(int flags) const
646 // No dynamic relocations in a static link!
647 if (parameters->doing_static_link())
650 // A reference to an undefined symbol from an executable should be
651 // statically resolved to 0, and does not need a dynamic relocation.
652 // This matches gnu ld behavior.
653 if (this->is_undefined() && !parameters->options().shared())
656 // A reference to an absolute symbol does not need a dynamic relocation.
657 if (this->is_absolute())
660 // An absolute reference within a position-independent output file
661 // will need a dynamic relocation.
662 if ((flags & ABSOLUTE_REF)
663 && parameters->options().output_is_position_independent())
666 // A function call that can branch to a local PLT entry does not need
667 // a dynamic relocation.
668 if ((flags & FUNCTION_CALL) && this->has_plt_offset())
671 // A reference to any PLT entry in a non-position-independent executable
672 // does not need a dynamic relocation.
673 if (!parameters->options().output_is_position_independent()
674 && this->has_plt_offset())
677 // A reference to a symbol defined in a dynamic object or to a
678 // symbol that is preemptible will need a dynamic relocation.
679 if (this->is_from_dynobj()
680 || this->is_undefined()
681 || this->is_preemptible())
684 // For all other cases, return FALSE.
688 // Whether we should use the PLT offset associated with a symbol for
689 // a relocation. FLAGS is a set of Reference_flags.
692 use_plt_offset(int flags) const
694 // If the symbol doesn't have a PLT offset, then naturally we
695 // don't want to use it.
696 if (!this->has_plt_offset())
699 // For a STT_GNU_IFUNC symbol we always have to use the PLT entry.
700 if (this->type() == elfcpp::STT_GNU_IFUNC)
703 // If we are going to generate a dynamic relocation, then we will
704 // wind up using that, so no need to use the PLT entry.
705 if (this->needs_dynamic_reloc(flags))
708 // If the symbol is from a dynamic object, we need to use the PLT
710 if (this->is_from_dynobj())
713 // If we are generating a shared object, and this symbol is
714 // undefined or preemptible, we need to use the PLT entry.
715 if (parameters->options().shared()
716 && (this->is_undefined() || this->is_preemptible()))
719 // If this is a call to a weak undefined symbol, we need to use
720 // the PLT entry; the symbol may be defined by a library loaded
722 if ((flags & FUNCTION_CALL) && this->is_weak_undefined())
725 // Otherwise we can use the regular definition.
729 // Given a direct absolute static relocation against
730 // the global symbol, where a dynamic relocation is needed, this
731 // function returns whether a relative dynamic relocation can be used.
732 // The caller must determine separately whether the static relocation
733 // is compatible with a relative relocation.
736 can_use_relative_reloc(bool is_function_call) const
738 // A function call that can branch to a local PLT entry can
739 // use a RELATIVE relocation.
740 if (is_function_call && this->has_plt_offset())
743 // A reference to a symbol defined in a dynamic object or to a
744 // symbol that is preemptible can not use a RELATIVE relocation.
745 if (this->is_from_dynobj()
746 || this->is_undefined()
747 || this->is_preemptible())
750 // For all other cases, return TRUE.
754 // Return the output section where this symbol is defined. Return
755 // NULL if the symbol has an absolute value.
757 output_section() const;
759 // Set the symbol's output section. This is used for symbols
760 // defined in scripts. This should only be called after the symbol
761 // table has been finalized.
763 set_output_section(Output_section*);
765 // Return whether there should be a warning for references to this
769 { return this->has_warning_; }
771 // Mark this symbol as having a warning.
774 { this->has_warning_ = true; }
776 // Return whether this symbol is defined by a COPY reloc from a
779 is_copied_from_dynobj() const
780 { return this->is_copied_from_dynobj_; }
782 // Mark this symbol as defined by a COPY reloc.
784 set_is_copied_from_dynobj()
785 { this->is_copied_from_dynobj_ = true; }
787 // Return whether this symbol is forced to visibility STB_LOCAL
788 // by a "local:" entry in a version script.
790 is_forced_local() const
791 { return this->is_forced_local_; }
793 // Mark this symbol as forced to STB_LOCAL visibility.
795 set_is_forced_local()
796 { this->is_forced_local_ = true; }
798 // Return true if this may need a COPY relocation.
799 // References from an executable object to non-function symbols
800 // defined in a dynamic object may need a COPY relocation.
802 may_need_copy_reloc() const
804 return (!parameters->options().output_is_position_independent()
805 && parameters->options().copyreloc()
806 && this->is_from_dynobj()
807 && !this->is_func());
810 // Return true if this symbol was predefined by the linker.
812 is_predefined() const
813 { return this->is_predefined_; }
816 // Instances of this class should always be created at a specific
819 { memset(this, 0, sizeof *this); }
821 // Initialize the general fields.
823 init_fields(const char* name, const char* version,
824 elfcpp::STT type, elfcpp::STB binding,
825 elfcpp::STV visibility, unsigned char nonvis);
827 // Initialize fields from an ELF symbol in OBJECT. ST_SHNDX is the
828 // section index, IS_ORDINARY is whether it is a normal section
829 // index rather than a special code.
830 template<int size, bool big_endian>
832 init_base_object(const char* name, const char* version, Object* object,
833 const elfcpp::Sym<size, big_endian>&, unsigned int st_shndx,
836 // Initialize fields for an Output_data.
838 init_base_output_data(const char* name, const char* version, Output_data*,
839 elfcpp::STT, elfcpp::STB, elfcpp::STV,
840 unsigned char nonvis, bool offset_is_from_end,
843 // Initialize fields for an Output_segment.
845 init_base_output_segment(const char* name, const char* version,
846 Output_segment* os, elfcpp::STT type,
847 elfcpp::STB binding, elfcpp::STV visibility,
848 unsigned char nonvis,
849 Segment_offset_base offset_base,
852 // Initialize fields for a constant.
854 init_base_constant(const char* name, const char* version, elfcpp::STT type,
855 elfcpp::STB binding, elfcpp::STV visibility,
856 unsigned char nonvis, bool is_predefined);
858 // Initialize fields for an undefined symbol.
860 init_base_undefined(const char* name, const char* version, elfcpp::STT type,
861 elfcpp::STB binding, elfcpp::STV visibility,
862 unsigned char nonvis);
864 // Override existing symbol.
865 template<int size, bool big_endian>
867 override_base(const elfcpp::Sym<size, big_endian>&, unsigned int st_shndx,
868 bool is_ordinary, Object* object, const char* version);
870 // Override existing symbol with a special symbol.
872 override_base_with_special(const Symbol* from);
874 // Override symbol version.
876 override_version(const char* version);
878 // Allocate a common symbol by giving it a location in the output
881 allocate_base_common(Output_data*);
884 Symbol(const Symbol&);
885 Symbol& operator=(const Symbol&);
887 // Symbol name (expected to point into a Stringpool).
889 // Symbol version (expected to point into a Stringpool). This may
891 const char* version_;
895 // This struct is used if SOURCE_ == FROM_OBJECT.
898 // Object in which symbol is defined, or in which it was first
901 // Section number in object_ in which symbol is defined.
905 // This struct is used if SOURCE_ == IN_OUTPUT_DATA.
908 // Output_data in which symbol is defined. Before
909 // Layout::finalize the symbol's value is an offset within the
911 Output_data* output_data;
912 // True if the offset is from the end, false if the offset is
913 // from the beginning.
914 bool offset_is_from_end;
917 // This struct is used if SOURCE_ == IN_OUTPUT_SEGMENT.
920 // Output_segment in which the symbol is defined. Before
921 // Layout::finalize the symbol's value is an offset.
922 Output_segment* output_segment;
923 // The base to use for the offset before Layout::finalize.
924 Segment_offset_base offset_base;
928 // The index of this symbol in the output file. If the symbol is
929 // not going into the output file, this value is -1U. This field
930 // starts as always holding zero. It is set to a non-zero value by
931 // Symbol_table::finalize.
932 unsigned int symtab_index_;
934 // The index of this symbol in the dynamic symbol table. If the
935 // symbol is not going into the dynamic symbol table, this value is
936 // -1U. This field starts as always holding zero. It is set to a
937 // non-zero value during Layout::finalize.
938 unsigned int dynsym_index_;
940 // The GOT section entries for this symbol. A symbol may have more
941 // than one GOT offset (e.g., when mixing modules compiled with two
942 // different TLS models), but will usually have at most one.
943 Got_offset_list got_offsets_;
945 // If this symbol has an entry in the PLT section, then this is the
946 // offset from the start of the PLT section. This is -1U if there
948 unsigned int plt_offset_;
950 // Symbol type (bits 0 to 3).
951 elfcpp::STT type_ : 4;
952 // Symbol binding (bits 4 to 7).
953 elfcpp::STB binding_ : 4;
954 // Symbol visibility (bits 8 to 9).
955 elfcpp::STV visibility_ : 2;
956 // Rest of symbol st_other field (bits 10 to 15).
957 unsigned int nonvis_ : 6;
958 // The type of symbol (bits 16 to 18).
960 // True if this is the default version of the symbol (bit 19).
962 // True if this symbol really forwards to another symbol. This is
963 // used when we discover after the fact that two different entries
964 // in the hash table really refer to the same symbol. This will
965 // never be set for a symbol found in the hash table, but may be set
966 // for a symbol found in the list of symbols attached to an Object.
967 // It forwards to the symbol found in the forwarders_ map of
968 // Symbol_table (bit 20).
969 bool is_forwarder_ : 1;
970 // True if the symbol has an alias in the weak_aliases table in
971 // Symbol_table (bit 21).
973 // True if this symbol needs to be in the dynamic symbol table (bit
975 bool needs_dynsym_entry_ : 1;
976 // True if we've seen this symbol in a regular object (bit 23).
978 // True if we've seen this symbol in a dynamic object (bit 24).
980 // True if this is a dynamic symbol which needs a special value in
981 // the dynamic symbol table (bit 25).
982 bool needs_dynsym_value_ : 1;
983 // True if there is a warning for this symbol (bit 26).
984 bool has_warning_ : 1;
985 // True if we are using a COPY reloc for this symbol, so that the
986 // real definition lives in a dynamic object (bit 27).
987 bool is_copied_from_dynobj_ : 1;
988 // True if this symbol was forced to local visibility by a version
990 bool is_forced_local_ : 1;
991 // True if the field u_.from_object.shndx is an ordinary section
992 // index, not one of the special codes from SHN_LORESERVE to
993 // SHN_HIRESERVE (bit 29).
994 bool is_ordinary_shndx_ : 1;
995 // True if we've seen this symbol in a real ELF object (bit 30).
996 bool in_real_elf_ : 1;
997 // True if this symbol is defined in a section which was discarded
999 bool is_defined_in_discarded_section_ : 1;
1000 // True if UNDEF_BINDING_WEAK_ has been set (bit 32).
1001 bool undef_binding_set_ : 1;
1002 // True if this symbol was a weak undef resolved by a dynamic def
1004 bool undef_binding_weak_ : 1;
1005 // True if this symbol is a predefined linker symbol (bit 34).
1006 bool is_predefined_ : 1;
1009 // The parts of a symbol which are size specific. Using a template
1010 // derived class like this helps us use less space on a 32-bit system.
1013 class Sized_symbol : public Symbol
1016 typedef typename elfcpp::Elf_types<size>::Elf_Addr Value_type;
1017 typedef typename elfcpp::Elf_types<size>::Elf_WXword Size_type;
1022 // Initialize fields from an ELF symbol in OBJECT. ST_SHNDX is the
1023 // section index, IS_ORDINARY is whether it is a normal section
1024 // index rather than a special code.
1025 template<bool big_endian>
1027 init_object(const char* name, const char* version, Object* object,
1028 const elfcpp::Sym<size, big_endian>&, unsigned int st_shndx,
1031 // Initialize fields for an Output_data.
1033 init_output_data(const char* name, const char* version, Output_data*,
1034 Value_type value, Size_type symsize, elfcpp::STT,
1035 elfcpp::STB, elfcpp::STV, unsigned char nonvis,
1036 bool offset_is_from_end, bool is_predefined);
1038 // Initialize fields for an Output_segment.
1040 init_output_segment(const char* name, const char* version, Output_segment*,
1041 Value_type value, Size_type symsize, elfcpp::STT,
1042 elfcpp::STB, elfcpp::STV, unsigned char nonvis,
1043 Segment_offset_base offset_base, bool is_predefined);
1045 // Initialize fields for a constant.
1047 init_constant(const char* name, const char* version, Value_type value,
1048 Size_type symsize, elfcpp::STT, elfcpp::STB, elfcpp::STV,
1049 unsigned char nonvis, bool is_predefined);
1051 // Initialize fields for an undefined symbol.
1053 init_undefined(const char* name, const char* version, elfcpp::STT,
1054 elfcpp::STB, elfcpp::STV, unsigned char nonvis);
1056 // Override existing symbol.
1057 template<bool big_endian>
1059 override(const elfcpp::Sym<size, big_endian>&, unsigned int st_shndx,
1060 bool is_ordinary, Object* object, const char* version);
1062 // Override existing symbol with a special symbol.
1064 override_with_special(const Sized_symbol<size>*);
1066 // Return the symbol's value.
1069 { return this->value_; }
1071 // Return the symbol's size (we can't call this 'size' because that
1072 // is a template parameter).
1075 { return this->symsize_; }
1077 // Set the symbol size. This is used when resolving common symbols.
1079 set_symsize(Size_type symsize)
1080 { this->symsize_ = symsize; }
1082 // Set the symbol value. This is called when we store the final
1083 // values of the symbols into the symbol table.
1085 set_value(Value_type value)
1086 { this->value_ = value; }
1088 // Allocate a common symbol by giving it a location in the output
1091 allocate_common(Output_data*, Value_type value);
1094 Sized_symbol(const Sized_symbol&);
1095 Sized_symbol& operator=(const Sized_symbol&);
1097 // Symbol value. Before Layout::finalize this is the offset in the
1098 // input section. This is set to the final value during
1099 // Layout::finalize.
1105 // A struct describing a symbol defined by the linker, where the value
1106 // of the symbol is defined based on an output section. This is used
1107 // for symbols defined by the linker, like "_init_array_start".
1109 struct Define_symbol_in_section
1113 // The name of the output section with which this symbol should be
1114 // associated. If there is no output section with that name, the
1115 // symbol will be defined as zero.
1116 const char* output_section;
1117 // The offset of the symbol within the output section. This is an
1118 // offset from the start of the output section, unless start_at_end
1119 // is true, in which case this is an offset from the end of the
1122 // The size of the symbol.
1126 // The symbol binding.
1127 elfcpp::STB binding;
1128 // The symbol visibility.
1129 elfcpp::STV visibility;
1130 // The rest of the st_other field.
1131 unsigned char nonvis;
1132 // If true, the value field is an offset from the end of the output
1134 bool offset_is_from_end;
1135 // If true, this symbol is defined only if we see a reference to it.
1139 // A struct describing a symbol defined by the linker, where the value
1140 // of the symbol is defined based on a segment. This is used for
1141 // symbols defined by the linker, like "_end". We describe the
1142 // segment with which the symbol should be associated by its
1143 // characteristics. If no segment meets these characteristics, the
1144 // symbol will be defined as zero. If there is more than one segment
1145 // which meets these characteristics, we will use the first one.
1147 struct Define_symbol_in_segment
1151 // The segment type where the symbol should be defined, typically
1153 elfcpp::PT segment_type;
1154 // Bitmask of segment flags which must be set.
1155 elfcpp::PF segment_flags_set;
1156 // Bitmask of segment flags which must be clear.
1157 elfcpp::PF segment_flags_clear;
1158 // The offset of the symbol within the segment. The offset is
1159 // calculated from the position set by offset_base.
1161 // The size of the symbol.
1165 // The symbol binding.
1166 elfcpp::STB binding;
1167 // The symbol visibility.
1168 elfcpp::STV visibility;
1169 // The rest of the st_other field.
1170 unsigned char nonvis;
1171 // The base from which we compute the offset.
1172 Symbol::Segment_offset_base offset_base;
1173 // If true, this symbol is defined only if we see a reference to it.
1177 // This class manages warnings. Warnings are a GNU extension. When
1178 // we see a section named .gnu.warning.SYM in an object file, and if
1179 // we wind using the definition of SYM from that object file, then we
1180 // will issue a warning for any relocation against SYM from a
1181 // different object file. The text of the warning is the contents of
1182 // the section. This is not precisely the definition used by the old
1183 // GNU linker; the old GNU linker treated an occurrence of
1184 // .gnu.warning.SYM as defining a warning symbol. A warning symbol
1185 // would trigger a warning on any reference. However, it was
1186 // inconsistent in that a warning in a dynamic object only triggered
1187 // if there was no definition in a regular object. This linker is
1188 // different in that we only issue a warning if we use the symbol
1189 // definition from the same object file as the warning section.
1198 // Add a warning for symbol NAME in object OBJ. WARNING is the text
1201 add_warning(Symbol_table* symtab, const char* name, Object* obj,
1202 const std::string& warning);
1204 // For each symbol for which we should give a warning, make a note
1207 note_warnings(Symbol_table* symtab);
1209 // Issue a warning for a reference to SYM at RELINFO's location.
1210 template<int size, bool big_endian>
1212 issue_warning(const Symbol* sym, const Relocate_info<size, big_endian>*,
1213 size_t relnum, off_t reloffset) const;
1216 Warnings(const Warnings&);
1217 Warnings& operator=(const Warnings&);
1219 // What we need to know to get the warning text.
1220 struct Warning_location
1222 // The object the warning is in.
1224 // The warning text.
1228 : object(NULL), text()
1232 set(Object* o, const std::string& t)
1239 // A mapping from warning symbol names (canonicalized in
1240 // Symbol_table's namepool_ field) to warning information.
1241 typedef Unordered_map<const char*, Warning_location> Warning_table;
1243 Warning_table warnings_;
1246 // The main linker symbol table.
1251 // The different places where a symbol definition can come from.
1254 // Defined in an object file--the normal case.
1256 // Defined for a COPY reloc.
1258 // Defined on the command line using --defsym.
1260 // Defined (so to speak) on the command line using -u.
1262 // Defined in a linker script.
1264 // Predefined by the linker.
1266 // Defined by the linker during an incremental base link, but not
1267 // a predefined symbol (e.g., common, defined in script).
1271 // The order in which we sort common symbols.
1272 enum Sort_commons_order
1274 SORT_COMMONS_BY_SIZE_DESCENDING,
1275 SORT_COMMONS_BY_ALIGNMENT_DESCENDING,
1276 SORT_COMMONS_BY_ALIGNMENT_ASCENDING
1279 // COUNT is an estimate of how many symbols will be inserted in the
1280 // symbol table. It's ok to put 0 if you don't know; a correct
1281 // guess will just save some CPU by reducing hashtable resizes.
1282 Symbol_table(unsigned int count, const Version_script_info& version_script);
1288 { this->icf_ = icf;}
1292 { return this->icf_; }
1294 // Returns true if ICF determined that this is a duplicate section.
1296 is_section_folded(Object* obj, unsigned int shndx) const;
1299 set_gc(Garbage_collection* gc)
1304 { return this->gc_; }
1306 // During garbage collection, this keeps undefined symbols.
1308 gc_mark_undef_symbols(Layout*);
1310 // During garbage collection, this ensures externally visible symbols
1311 // are not treated as garbage while building shared objects.
1313 gc_mark_symbol_for_shlib(Symbol* sym);
1315 // During garbage collection, this keeps sections that correspond to
1316 // symbols seen in dynamic objects.
1318 gc_mark_dyn_syms(Symbol* sym);
1320 // Add COUNT external symbols from the relocatable object RELOBJ to
1321 // the symbol table. SYMS is the symbols, SYMNDX_OFFSET is the
1322 // offset in the symbol table of the first symbol, SYM_NAMES is
1323 // their names, SYM_NAME_SIZE is the size of SYM_NAMES. This sets
1324 // SYMPOINTERS to point to the symbols in the symbol table. It sets
1325 // *DEFINED to the number of defined symbols.
1326 template<int size, bool big_endian>
1328 add_from_relobj(Sized_relobj_file<size, big_endian>* relobj,
1329 const unsigned char* syms, size_t count,
1330 size_t symndx_offset, const char* sym_names,
1331 size_t sym_name_size,
1332 typename Sized_relobj_file<size, big_endian>::Symbols*,
1335 // Add one external symbol from the plugin object OBJ to the symbol table.
1336 // Returns a pointer to the resolved symbol in the symbol table.
1337 template<int size, bool big_endian>
1339 add_from_pluginobj(Sized_pluginobj<size, big_endian>* obj,
1340 const char* name, const char* ver,
1341 elfcpp::Sym<size, big_endian>* sym);
1343 // Add COUNT dynamic symbols from the dynamic object DYNOBJ to the
1344 // symbol table. SYMS is the symbols. SYM_NAMES is their names.
1345 // SYM_NAME_SIZE is the size of SYM_NAMES. The other parameters are
1346 // symbol version data.
1347 template<int size, bool big_endian>
1349 add_from_dynobj(Sized_dynobj<size, big_endian>* dynobj,
1350 const unsigned char* syms, size_t count,
1351 const char* sym_names, size_t sym_name_size,
1352 const unsigned char* versym, size_t versym_size,
1353 const std::vector<const char*>*,
1354 typename Sized_relobj_file<size, big_endian>::Symbols*,
1357 // Add one external symbol from the incremental object OBJ to the symbol
1358 // table. Returns a pointer to the resolved symbol in the symbol table.
1359 template<int size, bool big_endian>
1361 add_from_incrobj(Object* obj, const char* name,
1362 const char* ver, elfcpp::Sym<size, big_endian>* sym);
1364 // Define a special symbol based on an Output_data. It is a
1365 // multiple definition error if this symbol is already defined.
1367 define_in_output_data(const char* name, const char* version, Defined,
1368 Output_data*, uint64_t value, uint64_t symsize,
1369 elfcpp::STT type, elfcpp::STB binding,
1370 elfcpp::STV visibility, unsigned char nonvis,
1371 bool offset_is_from_end, bool only_if_ref);
1373 // Define a special symbol based on an Output_segment. It is a
1374 // multiple definition error if this symbol is already defined.
1376 define_in_output_segment(const char* name, const char* version, Defined,
1377 Output_segment*, uint64_t value, uint64_t symsize,
1378 elfcpp::STT type, elfcpp::STB binding,
1379 elfcpp::STV visibility, unsigned char nonvis,
1380 Symbol::Segment_offset_base, bool only_if_ref);
1382 // Define a special symbol with a constant value. It is a multiple
1383 // definition error if this symbol is already defined.
1385 define_as_constant(const char* name, const char* version, Defined,
1386 uint64_t value, uint64_t symsize, elfcpp::STT type,
1387 elfcpp::STB binding, elfcpp::STV visibility,
1388 unsigned char nonvis, bool only_if_ref,
1389 bool force_override);
1391 // Define a set of symbols in output sections. If ONLY_IF_REF is
1392 // true, only define them if they are referenced.
1394 define_symbols(const Layout*, int count, const Define_symbol_in_section*,
1397 // Define a set of symbols in output segments. If ONLY_IF_REF is
1398 // true, only defined them if they are referenced.
1400 define_symbols(const Layout*, int count, const Define_symbol_in_segment*,
1403 // Define SYM using a COPY reloc. POSD is the Output_data where the
1404 // symbol should be defined--typically a .dyn.bss section. VALUE is
1405 // the offset within POSD.
1408 define_with_copy_reloc(Sized_symbol<size>* sym, Output_data* posd,
1409 typename elfcpp::Elf_types<size>::Elf_Addr);
1411 // Look up a symbol.
1413 lookup(const char*, const char* version = NULL) const;
1415 // Return the real symbol associated with the forwarder symbol FROM.
1417 resolve_forwards(const Symbol* from) const;
1419 // Return the sized version of a symbol in this table.
1422 get_sized_symbol(Symbol*) const;
1425 const Sized_symbol<size>*
1426 get_sized_symbol(const Symbol*) const;
1428 // Return the count of undefined symbols seen.
1430 saw_undefined() const
1431 { return this->saw_undefined_; }
1433 // Allocate the common symbols
1435 allocate_commons(Layout*, Mapfile*);
1437 // Add a warning for symbol NAME in object OBJ. WARNING is the text
1440 add_warning(const char* name, Object* obj, const std::string& warning)
1441 { this->warnings_.add_warning(this, name, obj, warning); }
1443 // Canonicalize a symbol name for use in the hash table.
1445 canonicalize_name(const char* name)
1446 { return this->namepool_.add(name, true, NULL); }
1448 // Possibly issue a warning for a reference to SYM at LOCATION which
1450 template<int size, bool big_endian>
1452 issue_warning(const Symbol* sym,
1453 const Relocate_info<size, big_endian>* relinfo,
1454 size_t relnum, off_t reloffset) const
1455 { this->warnings_.issue_warning(sym, relinfo, relnum, reloffset); }
1457 // Check candidate_odr_violations_ to find symbols with the same name
1458 // but apparently different definitions (different source-file/line-no).
1460 detect_odr_violations(const Task*, const char* output_file_name) const;
1462 // Add any undefined symbols named on the command line to the symbol
1465 add_undefined_symbols_from_command_line(Layout*);
1467 // SYM is defined using a COPY reloc. Return the dynamic object
1468 // where the original definition was found.
1470 get_copy_source(const Symbol* sym) const;
1472 // Set the dynamic symbol indexes. INDEX is the index of the first
1473 // global dynamic symbol. Pointers to the symbols are stored into
1474 // the vector. The names are stored into the Stringpool. This
1475 // returns an updated dynamic symbol index.
1477 set_dynsym_indexes(unsigned int index, std::vector<Symbol*>*,
1478 Stringpool*, Versions*);
1480 // Finalize the symbol table after we have set the final addresses
1481 // of all the input sections. This sets the final symbol indexes,
1482 // values and adds the names to *POOL. *PLOCAL_SYMCOUNT is the
1483 // index of the first global symbol. OFF is the file offset of the
1484 // global symbol table, DYNOFF is the offset of the globals in the
1485 // dynamic symbol table, DYN_GLOBAL_INDEX is the index of the first
1486 // global dynamic symbol, and DYNCOUNT is the number of global
1487 // dynamic symbols. This records the parameters, and returns the
1488 // new file offset. It updates *PLOCAL_SYMCOUNT if it created any
1491 finalize(off_t off, off_t dynoff, size_t dyn_global_index, size_t dyncount,
1492 Stringpool* pool, unsigned int* plocal_symcount);
1494 // Set the final file offset of the symbol table.
1496 set_file_offset(off_t off)
1497 { this->offset_ = off; }
1499 // Status code of Symbol_table::compute_final_value.
1500 enum Compute_final_value_status
1504 // Unsupported symbol section.
1505 CFVS_UNSUPPORTED_SYMBOL_SECTION,
1506 // No output section.
1507 CFVS_NO_OUTPUT_SECTION
1510 // Compute the final value of SYM and store status in location PSTATUS.
1511 // During relaxation, this may be called multiple times for a symbol to
1512 // compute its would-be final value in each relaxation pass.
1515 typename Sized_symbol<size>::Value_type
1516 compute_final_value(const Sized_symbol<size>* sym,
1517 Compute_final_value_status* pstatus) const;
1519 // Return the index of the first global symbol.
1521 first_global_index() const
1522 { return this->first_global_index_; }
1524 // Return the total number of symbols in the symbol table.
1526 output_count() const
1527 { return this->output_count_; }
1529 // Write out the global symbols.
1531 write_globals(const Stringpool*, const Stringpool*,
1532 Output_symtab_xindex*, Output_symtab_xindex*,
1533 Output_file*) const;
1535 // Write out a section symbol. Return the updated offset.
1537 write_section_symbol(const Output_section*, Output_symtab_xindex*,
1538 Output_file*, off_t) const;
1540 // Loop over all symbols, applying the function F to each.
1541 template<int size, typename F>
1543 for_all_symbols(F f) const
1545 for (Symbol_table_type::const_iterator p = this->table_.begin();
1546 p != this->table_.end();
1549 Sized_symbol<size>* sym = static_cast<Sized_symbol<size>*>(p->second);
1554 // Dump statistical information to stderr.
1556 print_stats() const;
1558 // Return the version script information.
1559 const Version_script_info&
1560 version_script() const
1561 { return version_script_; }
1564 Symbol_table(const Symbol_table&);
1565 Symbol_table& operator=(const Symbol_table&);
1567 // The type of the list of common symbols.
1568 typedef std::vector<Symbol*> Commons_type;
1570 // The type of the symbol hash table.
1572 typedef std::pair<Stringpool::Key, Stringpool::Key> Symbol_table_key;
1574 // The hash function. The key values are Stringpool keys.
1575 struct Symbol_table_hash
1578 operator()(const Symbol_table_key& key) const
1580 return key.first ^ key.second;
1584 struct Symbol_table_eq
1587 operator()(const Symbol_table_key&, const Symbol_table_key&) const;
1590 typedef Unordered_map<Symbol_table_key, Symbol*, Symbol_table_hash,
1591 Symbol_table_eq> Symbol_table_type;
1593 // A map from symbol name (as a pointer into the namepool) to all
1594 // the locations the symbols is (weakly) defined (and certain other
1595 // conditions are met). This map will be used later to detect
1596 // possible One Definition Rule (ODR) violations.
1597 struct Symbol_location
1599 Object* object; // Object where the symbol is defined.
1600 unsigned int shndx; // Section-in-object where the symbol is defined.
1601 off_t offset; // Offset-in-section where the symbol is defined.
1602 bool operator==(const Symbol_location& that) const
1604 return (this->object == that.object
1605 && this->shndx == that.shndx
1606 && this->offset == that.offset);
1610 struct Symbol_location_hash
1612 size_t operator()(const Symbol_location& loc) const
1613 { return reinterpret_cast<uintptr_t>(loc.object) ^ loc.offset ^ loc.shndx; }
1616 typedef Unordered_map<const char*,
1617 Unordered_set<Symbol_location, Symbol_location_hash> >
1620 // Make FROM a forwarder symbol to TO.
1622 make_forwarder(Symbol* from, Symbol* to);
1625 template<int size, bool big_endian>
1627 add_from_object(Object*, const char* name, Stringpool::Key name_key,
1628 const char* version, Stringpool::Key version_key,
1629 bool def, const elfcpp::Sym<size, big_endian>& sym,
1630 unsigned int st_shndx, bool is_ordinary,
1631 unsigned int orig_st_shndx);
1633 // Define a default symbol.
1634 template<int size, bool big_endian>
1636 define_default_version(Sized_symbol<size>*, bool,
1637 Symbol_table_type::iterator);
1640 template<int size, bool big_endian>
1642 resolve(Sized_symbol<size>* to,
1643 const elfcpp::Sym<size, big_endian>& sym,
1644 unsigned int st_shndx, bool is_ordinary,
1645 unsigned int orig_st_shndx,
1646 Object*, const char* version);
1648 template<int size, bool big_endian>
1650 resolve(Sized_symbol<size>* to, const Sized_symbol<size>* from);
1652 // Record that a symbol is forced to be local by a version script or
1655 force_local(Symbol*);
1657 // Adjust NAME and *NAME_KEY for wrapping.
1659 wrap_symbol(const char* name, Stringpool::Key* name_key);
1661 // Whether we should override a symbol, based on flags in
1664 should_override(const Symbol*, unsigned int, elfcpp::STT, Defined,
1665 Object*, bool*, bool*);
1667 // Report a problem in symbol resolution.
1669 report_resolve_problem(bool is_error, const char* msg, const Symbol* to,
1670 Defined, Object* object);
1672 // Override a symbol.
1673 template<int size, bool big_endian>
1675 override(Sized_symbol<size>* tosym,
1676 const elfcpp::Sym<size, big_endian>& fromsym,
1677 unsigned int st_shndx, bool is_ordinary,
1678 Object* object, const char* version);
1680 // Whether we should override a symbol with a special symbol which
1681 // is automatically defined by the linker.
1683 should_override_with_special(const Symbol*, elfcpp::STT, Defined);
1685 // Override a symbol with a special symbol.
1688 override_with_special(Sized_symbol<size>* tosym,
1689 const Sized_symbol<size>* fromsym);
1691 // Record all weak alias sets for a dynamic object.
1694 record_weak_aliases(std::vector<Sized_symbol<size>*>*);
1696 // Define a special symbol.
1697 template<int size, bool big_endian>
1699 define_special_symbol(const char** pname, const char** pversion,
1700 bool only_if_ref, Sized_symbol<size>** poldsym,
1701 bool* resolve_oldsym);
1703 // Define a symbol in an Output_data, sized version.
1706 do_define_in_output_data(const char* name, const char* version, Defined,
1708 typename elfcpp::Elf_types<size>::Elf_Addr value,
1709 typename elfcpp::Elf_types<size>::Elf_WXword ssize,
1710 elfcpp::STT type, elfcpp::STB binding,
1711 elfcpp::STV visibility, unsigned char nonvis,
1712 bool offset_is_from_end, bool only_if_ref);
1714 // Define a symbol in an Output_segment, sized version.
1717 do_define_in_output_segment(
1718 const char* name, const char* version, Defined, Output_segment* os,
1719 typename elfcpp::Elf_types<size>::Elf_Addr value,
1720 typename elfcpp::Elf_types<size>::Elf_WXword ssize,
1721 elfcpp::STT type, elfcpp::STB binding,
1722 elfcpp::STV visibility, unsigned char nonvis,
1723 Symbol::Segment_offset_base offset_base, bool only_if_ref);
1725 // Define a symbol as a constant, sized version.
1728 do_define_as_constant(
1729 const char* name, const char* version, Defined,
1730 typename elfcpp::Elf_types<size>::Elf_Addr value,
1731 typename elfcpp::Elf_types<size>::Elf_WXword ssize,
1732 elfcpp::STT type, elfcpp::STB binding,
1733 elfcpp::STV visibility, unsigned char nonvis,
1734 bool only_if_ref, bool force_override);
1736 // Add any undefined symbols named on the command line to the symbol
1737 // table, sized version.
1740 do_add_undefined_symbols_from_command_line(Layout*);
1742 // Add one undefined symbol.
1745 add_undefined_symbol_from_command_line(const char* name);
1747 // Types of common symbols.
1749 enum Commons_section_type
1757 // Allocate the common symbols, sized version.
1760 do_allocate_commons(Layout*, Mapfile*, Sort_commons_order);
1762 // Allocate the common symbols from one list.
1765 do_allocate_commons_list(Layout*, Commons_section_type, Commons_type*,
1766 Mapfile*, Sort_commons_order);
1768 // Returns all of the lines attached to LOC, not just the one the
1769 // instruction actually came from. This helps the ODR checker avoid
1771 static std::vector<std::string>
1772 linenos_from_loc(const Task* task, const Symbol_location& loc);
1774 // Implement detect_odr_violations.
1775 template<int size, bool big_endian>
1777 sized_detect_odr_violations() const;
1779 // Finalize symbols specialized for size.
1782 sized_finalize(off_t, Stringpool*, unsigned int*);
1784 // Finalize a symbol. Return whether it should be added to the
1788 sized_finalize_symbol(Symbol*);
1790 // Add a symbol the final symtab by setting its index.
1793 add_to_final_symtab(Symbol*, Stringpool*, unsigned int* pindex, off_t* poff);
1795 // Write globals specialized for size and endianness.
1796 template<int size, bool big_endian>
1798 sized_write_globals(const Stringpool*, const Stringpool*,
1799 Output_symtab_xindex*, Output_symtab_xindex*,
1800 Output_file*) const;
1802 // Write out a symbol to P.
1803 template<int size, bool big_endian>
1805 sized_write_symbol(Sized_symbol<size>*,
1806 typename elfcpp::Elf_types<size>::Elf_Addr value,
1807 unsigned int shndx, elfcpp::STB,
1808 const Stringpool*, unsigned char* p) const;
1810 // Possibly warn about an undefined symbol from a dynamic object.
1812 warn_about_undefined_dynobj_symbol(Symbol*) const;
1814 // Write out a section symbol, specialized for size and endianness.
1815 template<int size, bool big_endian>
1817 sized_write_section_symbol(const Output_section*, Output_symtab_xindex*,
1818 Output_file*, off_t) const;
1820 // The type of the list of symbols which have been forced local.
1821 typedef std::vector<Symbol*> Forced_locals;
1823 // A map from symbols with COPY relocs to the dynamic objects where
1824 // they are defined.
1825 typedef Unordered_map<const Symbol*, Dynobj*> Copied_symbol_dynobjs;
1827 // We increment this every time we see a new undefined symbol, for
1828 // use in archive groups.
1829 size_t saw_undefined_;
1830 // The index of the first global symbol in the output file.
1831 unsigned int first_global_index_;
1832 // The file offset within the output symtab section where we should
1835 // The number of global symbols we want to write out.
1836 unsigned int output_count_;
1837 // The file offset of the global dynamic symbols, or 0 if none.
1838 off_t dynamic_offset_;
1839 // The index of the first global dynamic symbol.
1840 unsigned int first_dynamic_global_index_;
1841 // The number of global dynamic symbols, or 0 if none.
1842 unsigned int dynamic_count_;
1843 // The symbol hash table.
1844 Symbol_table_type table_;
1845 // A pool of symbol names. This is used for all global symbols.
1846 // Entries in the hash table point into this pool.
1847 Stringpool namepool_;
1848 // Forwarding symbols.
1849 Unordered_map<const Symbol*, Symbol*> forwarders_;
1850 // Weak aliases. A symbol in this list points to the next alias.
1851 // The aliases point to each other in a circular list.
1852 Unordered_map<Symbol*, Symbol*> weak_aliases_;
1853 // We don't expect there to be very many common symbols, so we keep
1854 // a list of them. When we find a common symbol we add it to this
1855 // list. It is possible that by the time we process the list the
1856 // symbol is no longer a common symbol. It may also have become a
1858 Commons_type commons_;
1859 // This is like the commons_ field, except that it holds TLS common
1861 Commons_type tls_commons_;
1862 // This is for small common symbols.
1863 Commons_type small_commons_;
1864 // This is for large common symbols.
1865 Commons_type large_commons_;
1866 // A list of symbols which have been forced to be local. We don't
1867 // expect there to be very many of them, so we keep a list of them
1868 // rather than walking the whole table to find them.
1869 Forced_locals forced_locals_;
1870 // Manage symbol warnings.
1872 // Manage potential One Definition Rule (ODR) violations.
1873 Odr_map candidate_odr_violations_;
1875 // When we emit a COPY reloc for a symbol, we define it in an
1876 // Output_data. When it's time to emit version information for it,
1877 // we need to know the dynamic object in which we found the original
1878 // definition. This maps symbols with COPY relocs to the dynamic
1879 // object where they were defined.
1880 Copied_symbol_dynobjs copied_symbol_dynobjs_;
1881 // Information parsed from the version script, if any.
1882 const Version_script_info& version_script_;
1883 Garbage_collection* gc_;
1887 // We inline get_sized_symbol for efficiency.
1891 Symbol_table::get_sized_symbol(Symbol* sym) const
1893 gold_assert(size == parameters->target().get_size());
1894 return static_cast<Sized_symbol<size>*>(sym);
1898 const Sized_symbol<size>*
1899 Symbol_table::get_sized_symbol(const Symbol* sym) const
1901 gold_assert(size == parameters->target().get_size());
1902 return static_cast<const Sized_symbol<size>*>(sym);
1905 } // End namespace gold.
1907 #endif // !defined(GOLD_SYMTAB_H)