X-Git-Url: http://drtracing.org/?a=blobdiff_plain;f=gold%2Fsymtab.cc;h=2e17529b455cee8c8a06df1aba1a3f7cf7696e3d;hb=5fb776a6371f2122e891467a8fe9b4d7b8b5c6a4;hp=8a9e6f103ae4392dc670b27ae119e46bbf141909;hpb=c0a628659598a06ce2b60c956763f075a2b64b30;p=deliverable%2Fbinutils-gdb.git diff --git a/gold/symtab.cc b/gold/symtab.cc index 8a9e6f103a..2e17529b45 100644 --- a/gold/symtab.cc +++ b/gold/symtab.cc @@ -1,6 +1,6 @@ // symtab.cc -- the gold symbol table -// Copyright 2006, 2007, 2008, 2009 Free Software Foundation, Inc. +// Copyright 2006, 2007, 2008, 2009, 2010, 2011 Free Software Foundation, Inc. // Written by Ian Lance Taylor . // This file is part of gold. @@ -38,8 +38,9 @@ #include "target.h" #include "workqueue.h" #include "symtab.h" -#include "demangle.h" // needed for --dynamic-list-cpp-new +#include "script.h" #include "plugin.h" +#include "incremental.h" namespace gold { @@ -59,24 +60,26 @@ Symbol::init_fields(const char* name, const char* version, this->symtab_index_ = 0; this->dynsym_index_ = 0; this->got_offsets_.init(); - this->plt_offset_ = 0; + this->plt_offset_ = -1U; this->type_ = type; this->binding_ = binding; this->visibility_ = visibility; this->nonvis_ = nonvis; - this->is_target_special_ = false; this->is_def_ = false; this->is_forwarder_ = false; this->has_alias_ = false; this->needs_dynsym_entry_ = false; this->in_reg_ = false; this->in_dyn_ = false; - this->has_plt_offset_ = false; this->has_warning_ = false; this->is_copied_from_dynobj_ = false; this->is_forced_local_ = false; this->is_ordinary_shndx_ = false; this->in_real_elf_ = false; + this->is_defined_in_discarded_section_ = false; + this->undef_binding_set_ = false; + this->undef_binding_weak_ = false; + this->is_predefined_ = false; } // Return the demangled version of the symbol's name, but only @@ -131,7 +134,8 @@ void Symbol::init_base_output_data(const char* name, const char* version, Output_data* od, elfcpp::STT type, elfcpp::STB binding, elfcpp::STV visibility, - unsigned char nonvis, bool offset_is_from_end) + unsigned char nonvis, bool offset_is_from_end, + bool is_predefined) { this->init_fields(name, version, type, binding, visibility, nonvis); this->u_.in_output_data.output_data = od; @@ -139,6 +143,7 @@ Symbol::init_base_output_data(const char* name, const char* version, this->source_ = IN_OUTPUT_DATA; this->in_reg_ = true; this->in_real_elf_ = true; + this->is_predefined_ = is_predefined; } // Initialize the fields in the base class Symbol for a symbol defined @@ -149,7 +154,8 @@ Symbol::init_base_output_segment(const char* name, const char* version, Output_segment* os, elfcpp::STT type, elfcpp::STB binding, elfcpp::STV visibility, unsigned char nonvis, - Segment_offset_base offset_base) + Segment_offset_base offset_base, + bool is_predefined) { this->init_fields(name, version, type, binding, visibility, nonvis); this->u_.in_output_segment.output_segment = os; @@ -157,6 +163,7 @@ Symbol::init_base_output_segment(const char* name, const char* version, this->source_ = IN_OUTPUT_SEGMENT; this->in_reg_ = true; this->in_real_elf_ = true; + this->is_predefined_ = is_predefined; } // Initialize the fields in the base class Symbol for a symbol defined @@ -165,12 +172,14 @@ Symbol::init_base_output_segment(const char* name, const char* version, void Symbol::init_base_constant(const char* name, const char* version, elfcpp::STT type, elfcpp::STB binding, - elfcpp::STV visibility, unsigned char nonvis) + elfcpp::STV visibility, unsigned char nonvis, + bool is_predefined) { this->init_fields(name, version, type, binding, visibility, nonvis); this->source_ = IS_CONSTANT; this->in_reg_ = true; this->in_real_elf_ = true; + this->is_predefined_ = is_predefined; } // Initialize the fields in the base class Symbol for an undefined @@ -225,10 +234,11 @@ Sized_symbol::init_output_data(const char* name, const char* version, elfcpp::STB binding, elfcpp::STV visibility, unsigned char nonvis, - bool offset_is_from_end) + bool offset_is_from_end, + bool is_predefined) { this->init_base_output_data(name, version, od, type, binding, visibility, - nonvis, offset_is_from_end); + nonvis, offset_is_from_end, is_predefined); this->value_ = value; this->symsize_ = symsize; } @@ -244,10 +254,11 @@ Sized_symbol::init_output_segment(const char* name, const char* version, elfcpp::STB binding, elfcpp::STV visibility, unsigned char nonvis, - Segment_offset_base offset_base) + Segment_offset_base offset_base, + bool is_predefined) { this->init_base_output_segment(name, version, os, type, binding, visibility, - nonvis, offset_base); + nonvis, offset_base, is_predefined); this->value_ = value; this->symsize_ = symsize; } @@ -260,9 +271,11 @@ void Sized_symbol::init_constant(const char* name, const char* version, Value_type value, Size_type symsize, elfcpp::STT type, elfcpp::STB binding, - elfcpp::STV visibility, unsigned char nonvis) + elfcpp::STV visibility, unsigned char nonvis, + bool is_predefined) { - this->init_base_constant(name, version, type, binding, visibility, nonvis); + this->init_base_constant(name, version, type, binding, visibility, nonvis, + is_predefined); this->value_ = value; this->symsize_ = symsize; } @@ -280,6 +293,21 @@ Sized_symbol::init_undefined(const char* name, const char* version, this->symsize_ = 0; } +// Return an allocated string holding the symbol's name as +// name@version. This is used for relocatable links. + +std::string +Symbol::versioned_name() const +{ + gold_assert(this->version_ != NULL); + std::string ret = this->name_; + ret.push_back('@'); + if (this->is_def_) + ret.push_back('@'); + ret += this->version_; + return ret; +} + // Return true if SHNDX represents a common symbol. bool @@ -307,8 +335,13 @@ Sized_symbol::allocate_common(Output_data* od, Value_type value) // table. inline bool -Symbol::should_add_dynsym_entry() const +Symbol::should_add_dynsym_entry(Symbol_table* symtab) const { + // If the symbol is only present on plugin files, the plugin decided we + // don't need it. + if (!this->in_real_elf()) + return false; + // If the symbol is used by a dynamic relocation, we need to add it. if (this->needs_dynsym_entry()) return true; @@ -325,18 +358,28 @@ Symbol::should_add_dynsym_entry() const bool is_ordinary; unsigned int shndx = this->shndx(&is_ordinary); if (is_ordinary && shndx != elfcpp::SHN_UNDEF - && !relobj->is_section_included(shndx)) + && !relobj->is_section_included(shndx) + && !symtab->is_section_folded(relobj, shndx)) return false; } + // If the symbol was forced dynamic in a --dynamic-list file + // or an --export-dynamic-symbol option, add it. + if (!this->is_from_dynobj() + && (parameters->options().in_dynamic_list(this->name()) + || parameters->options().is_export_dynamic_symbol(this->name()))) + { + if (!this->is_forced_local()) + return true; + gold_warning(_("Cannot export local symbol '%s'"), + this->demangled_name().c_str()); + return false; + } + // If the symbol was forced local in a version script, do not add it. if (this->is_forced_local()) return false; - // If the symbol was forced dynamic in a --dynamic-list file, add it. - if (parameters->options().in_dynamic_list(this->name())) - return true; - // If dynamic-list-data was specified, add any STT_OBJECT. if (parameters->options().dynamic_list_data() && !this->is_from_dynobj() @@ -380,6 +423,7 @@ Symbol::should_add_dynsym_entry() const // externally visible, we need to add it. if ((parameters->options().export_dynamic() || parameters->options().shared()) && !this->is_from_dynobj() + && !this->is_undefined() && this->is_externally_visible()) return true; @@ -394,7 +438,8 @@ Symbol::final_value_is_known() const { // If we are not generating an executable, then no final values are // known, since they will change at runtime. - if (parameters->options().shared() || parameters->options().relocatable()) + if (parameters->options().output_is_position_independent() + || parameters->options().relocatable()) return false; // If the symbol is not from an object file, and is not undefined, @@ -498,14 +543,6 @@ Symbol_table::~Symbol_table() { } -// The hash function. The key values are Stringpool keys. - -inline size_t -Symbol_table::Symbol_table_hash::operator()(const Symbol_table_key& key) const -{ - return key.first ^ key.second; -} - // The symbol table key equality function. This is called with // Stringpool keys. @@ -519,15 +556,15 @@ Symbol_table::Symbol_table_eq::operator()(const Symbol_table_key& k1, bool Symbol_table::is_section_folded(Object* obj, unsigned int shndx) const { - return (parameters->options().icf() + return (parameters->options().icf_enabled() && this->icf_->is_section_folded(obj, shndx)); } -// For symbols that have been listed with -u option, add them to the -// work list to avoid gc'ing them. +// For symbols that have been listed with a -u or --export-dynamic-symbol +// option, add them to the work list to avoid gc'ing them. void -Symbol_table::gc_mark_undef_symbols() +Symbol_table::gc_mark_undef_symbols(Layout* layout) { for (options::String_set::const_iterator p = parameters->options().undefined_begin(); @@ -536,38 +573,58 @@ Symbol_table::gc_mark_undef_symbols() { const char* name = p->c_str(); Symbol* sym = this->lookup(name); - gold_assert (sym != NULL); + gold_assert(sym != NULL); if (sym->source() == Symbol::FROM_OBJECT && !sym->object()->is_dynamic()) { - Relobj* obj = static_cast(sym->object()); - bool is_ordinary; - unsigned int shndx = sym->shndx(&is_ordinary); - if (is_ordinary) - { - gold_assert(this->gc_ != NULL); - this->gc_->worklist().push(Section_id(obj, shndx)); - } + this->gc_mark_symbol(sym); } } + + for (options::String_set::const_iterator p = + parameters->options().export_dynamic_symbol_begin(); + p != parameters->options().export_dynamic_symbol_end(); + ++p) + { + const char* name = p->c_str(); + Symbol* sym = this->lookup(name); + // It's not an error if a symbol named by --export-dynamic-symbol + // is undefined. + if (sym != NULL + && sym->source() == Symbol::FROM_OBJECT + && !sym->object()->is_dynamic()) + { + this->gc_mark_symbol(sym); + } + } + + for (Script_options::referenced_const_iterator p = + layout->script_options()->referenced_begin(); + p != layout->script_options()->referenced_end(); + ++p) + { + Symbol* sym = this->lookup(p->c_str()); + gold_assert(sym != NULL); + if (sym->source() == Symbol::FROM_OBJECT + && !sym->object()->is_dynamic()) + { + this->gc_mark_symbol(sym); + } + } } void -Symbol_table::gc_mark_symbol_for_shlib(Symbol* sym) +Symbol_table::gc_mark_symbol(Symbol* sym) { - if (!sym->is_from_dynobj() - && sym->is_externally_visible()) + // Add the object and section to the work list. + bool is_ordinary; + unsigned int shndx = sym->shndx(&is_ordinary); + if (is_ordinary && shndx != elfcpp::SHN_UNDEF) { - //Add the object and section to the work list. - Relobj* obj = static_cast(sym->object()); - bool is_ordinary; - unsigned int shndx = sym->shndx(&is_ordinary); - if (is_ordinary && shndx != elfcpp::SHN_UNDEF) - { - gold_assert(this->gc_!= NULL); - this->gc_->worklist().push(Section_id(obj, shndx)); - } + gold_assert(this->gc_!= NULL); + this->gc_->worklist().push(Section_id(sym->object(), shndx)); } + parameters->target().gc_mark_symbol(this, sym); } // When doing garbage collection, keep symbols that have been seen in @@ -577,16 +634,7 @@ Symbol_table::gc_mark_dyn_syms(Symbol* sym) { if (sym->in_dyn() && sym->source() == Symbol::FROM_OBJECT && !sym->object()->is_dynamic()) - { - Relobj *obj = static_cast(sym->object()); - bool is_ordinary; - unsigned int shndx = sym->shndx(&is_ordinary); - if (is_ordinary && shndx != elfcpp::SHN_UNDEF) - { - gold_assert(this->gc_ != NULL); - this->gc_->worklist().push(Section_id(obj, shndx)); - } - } + this->gc_mark_symbol(sym); } // Make TO a symbol which forwards to FROM. @@ -812,13 +860,13 @@ Symbol_table::define_default_version(Sized_symbol* sym, // section index; IS_ORDINARY is whether this is a normal section // rather than a special code. -// If DEF is true, then this is the definition of a default version of -// a symbol. That means that any lookup of NAME/NULL and any lookup -// of NAME/VERSION should always return the same symbol. This is -// obvious for references, but in particular we want to do this for -// definitions: overriding NAME/NULL should also override -// NAME/VERSION. If we don't do that, it would be very hard to -// override functions in a shared library which uses versioning. +// If IS_DEFAULT_VERSION is true, then this is the definition of a +// default version of a symbol. That means that any lookup of +// NAME/NULL and any lookup of NAME/VERSION should always return the +// same symbol. This is obvious for references, but in particular we +// want to do this for definitions: overriding NAME/NULL should also +// override NAME/VERSION. If we don't do that, it would be very hard +// to override functions in a shared library which uses versioning. // We implement this by simply making both entries in the hash table // point to the same Symbol structure. That is easy enough if this is @@ -839,11 +887,11 @@ Symbol_table::define_default_version(Sized_symbol* sym, template Sized_symbol* Symbol_table::add_from_object(Object* object, - const char *name, + const char* name, Stringpool::Key name_key, - const char *version, + const char* version, Stringpool::Key version_key, - bool def, + bool is_default_version, const elfcpp::Sym& sym, unsigned int st_shndx, bool is_ordinary, @@ -882,14 +930,14 @@ Symbol_table::add_from_object(Object* object, this->table_.insert(std::make_pair(std::make_pair(name_key, version_key), snull)); - std::pair insdef = + std::pair insdefault = std::make_pair(this->table_.end(), false); - if (def) + if (is_default_version) { const Stringpool::Key vnull_key = 0; - insdef = this->table_.insert(std::make_pair(std::make_pair(name_key, - vnull_key), - snull)); + insdefault = this->table_.insert(std::make_pair(std::make_pair(name_key, + vnull_key), + snull)); } // ins.first: an iterator, which is a pointer to a pair. @@ -914,20 +962,20 @@ Symbol_table::add_from_object(Object* object, if (parameters->options().gc_sections()) this->gc_mark_dyn_syms(ret); - if (def) - this->define_default_version(ret, insdef.second, - insdef.first); + if (is_default_version) + this->define_default_version(ret, insdefault.second, + insdefault.first); } else { // This is the first time we have seen NAME/VERSION. gold_assert(ins.first->second == NULL); - if (def && !insdef.second) + if (is_default_version && !insdefault.second) { // We already have an entry for NAME/NULL. If we override // it, then change it to NAME/VERSION. - ret = this->get_sized_symbol(insdef.first->second); + ret = this->get_sized_symbol(insdefault.first->second); was_undefined = ret->is_undefined(); was_common = ret->is_common(); @@ -954,12 +1002,12 @@ Symbol_table::add_from_object(Object* object, { // This means that we don't want a symbol table // entry after all. - if (!def) + if (!is_default_version) this->table_.erase(ins.first); else { - this->table_.erase(insdef.first); - // Inserting insdef invalidated ins. + this->table_.erase(insdefault.first); + // Inserting INSDEFAULT invalidated INS. this->table_.erase(std::make_pair(name_key, version_key)); } @@ -970,23 +1018,27 @@ Symbol_table::add_from_object(Object* object, ret->init_object(name, version, object, sym, st_shndx, is_ordinary); ins.first->second = ret; - if (def) + if (is_default_version) { // This is the first time we have seen NAME/NULL. Point // it at the new entry for NAME/VERSION. - gold_assert(insdef.second); - insdef.first->second = ret; + gold_assert(insdefault.second); + insdefault.first->second = ret; } } - if (def) + if (is_default_version) ret->set_is_default(); } // Record every time we see a new undefined symbol, to speed up // archive groups. if (!was_undefined && ret->is_undefined()) - ++this->saw_undefined_; + { + ++this->saw_undefined_; + if (parameters->options().has_plugins()) + parameters->options().plugins()->new_undefined_symbol(ret); + } // Keep track of common symbols, to speed up common symbol // allocation. @@ -1009,6 +1061,7 @@ Symbol_table::add_from_object(Object* object, if ((ret->visibility() == elfcpp::STV_HIDDEN || ret->visibility() == elfcpp::STV_INTERNAL) && (ret->binding() == elfcpp::STB_GLOBAL + || ret->binding() == elfcpp::STB_GNU_UNIQUE || ret->binding() == elfcpp::STB_WEAK) && !parameters->options().relocatable()) this->force_local(ret); @@ -1021,14 +1074,14 @@ Symbol_table::add_from_object(Object* object, template void Symbol_table::add_from_relobj( - Sized_relobj* relobj, + Sized_relobj_file* relobj, const unsigned char* syms, size_t count, size_t symndx_offset, const char* sym_names, size_t sym_name_size, - typename Sized_relobj::Symbols* sympointers, - size_t *defined) + typename Sized_relobj_file::Symbols* sympointers, + size_t* defined) { *defined = 0; @@ -1068,10 +1121,15 @@ Symbol_table::add_from_relobj( // A symbol defined in a section which we are not including must // be treated as an undefined symbol. + bool is_defined_in_discarded_section = false; if (st_shndx != elfcpp::SHN_UNDEF && is_ordinary - && !relobj->is_section_included(st_shndx)) - st_shndx = elfcpp::SHN_UNDEF; + && !relobj->is_section_included(st_shndx) + && !this->is_section_folded(relobj, st_shndx)) + { + st_shndx = elfcpp::SHN_UNDEF; + is_defined_in_discarded_section = true; + } // In an object file, an '@' in the name separates the symbol // name from the version name. If there are two '@' characters, @@ -1079,9 +1137,18 @@ Symbol_table::add_from_relobj( const char* ver = strchr(name, '@'); Stringpool::Key ver_key = 0; int namelen = 0; - // DEF: is the version default? LOCAL: is the symbol forced local? - bool def = false; - bool local = false; + // IS_DEFAULT_VERSION: is the version default? + // IS_FORCED_LOCAL: is the symbol forced local? + bool is_default_version = false; + bool is_forced_local = false; + + // FIXME: For incremental links, we don't store version information, + // so we need to ignore version symbols for now. + if (parameters->incremental_update() && ver != NULL) + { + namelen = ver - name; + ver = NULL; + } if (ver != NULL) { @@ -1090,7 +1157,7 @@ Symbol_table::add_from_relobj( ++ver; if (*ver == '@') { - def = true; + is_default_version = true; ++ver; } ver = this->namepool_.add(ver, true, &ver_key); @@ -1107,21 +1174,21 @@ Symbol_table::add_from_relobj( // The symbol name did not have a version, but the // version script may assign a version anyway. std::string version; - if (this->version_script_.get_symbol_version(name, &version)) + bool is_global; + if (this->version_script_.get_symbol_version(name, &version, + &is_global)) { - // The version can be empty if the version script is - // only used to force some symbols to be local. - if (!version.empty()) + if (!is_global) + is_forced_local = true; + else if (!version.empty()) { ver = this->namepool_.add_with_length(version.c_str(), version.length(), true, &ver_key); - def = true; + is_default_version = true; } } - else if (this->version_script_.symbol_is_local(name)) - local = true; } } @@ -1132,12 +1199,14 @@ Symbol_table::add_from_relobj( { memcpy(symbuf, p, sym_size); elfcpp::Sym_write sw(symbuf); - if (orig_st_shndx != elfcpp::SHN_UNDEF && is_ordinary) + if (orig_st_shndx != elfcpp::SHN_UNDEF + && is_ordinary + && relobj->e_type() == elfcpp::ET_REL) { - // Symbol values in object files are section relative. - // This is normally what we want, but since here we are - // converting the symbol to absolute we need to add the - // section address. The section address in an object + // Symbol values in relocatable object files are section + // relative. This is normally what we want, but since here + // we are converting the symbol to absolute we need to add + // the section address. The section address in an object // file is normally zero, but people can use a linker // script to change it. sw.put_st_value(sym.get_st_value() @@ -1149,7 +1218,8 @@ Symbol_table::add_from_relobj( } // Fix up visibility if object has no-export set. - if (relobj->no_export()) + if (relobj->no_export() + && (orig_st_shndx != elfcpp::SHN_UNDEF || !is_ordinary)) { // We may have copied symbol already above. if (psym != &sym2) @@ -1174,18 +1244,26 @@ Symbol_table::add_from_relobj( Sized_symbol* res; res = this->add_from_object(relobj, name, name_key, ver, ver_key, - def, *psym, st_shndx, is_ordinary, - orig_st_shndx); + is_default_version, *psym, st_shndx, + is_ordinary, orig_st_shndx); - // If building a shared library using garbage collection, do not - // treat externally visible symbols as garbage. - if (parameters->options().gc_sections() - && parameters->options().shared()) - this->gc_mark_symbol_for_shlib(res); - - if (local) + if (is_forced_local) this->force_local(res); + // Do not treat this symbol as garbage if this symbol will be + // exported to the dynamic symbol table. This is true when + // building a shared library or using --export-dynamic and + // the symbol is externally visible. + if (parameters->options().gc_sections() + && res->is_externally_visible() + && !res->is_from_dynobj() + && (parameters->options().shared() + || parameters->options().export_dynamic())) + this->gc_mark_symbol(res); + + if (is_defined_in_discarded_section) + res->set_is_defined_in_discarded_section(); + (*sympointers)[i] = res; } } @@ -1201,10 +1279,11 @@ Symbol_table::add_from_pluginobj( elfcpp::Sym* sym) { unsigned int st_shndx = sym->get_st_shndx(); + bool is_ordinary = st_shndx < elfcpp::SHN_LORESERVE; Stringpool::Key ver_key = 0; - bool def = false; - bool local = false; + bool is_default_version = false; + bool is_forced_local = false; if (ver != NULL) { @@ -1221,21 +1300,21 @@ Symbol_table::add_from_pluginobj( // The symbol name did not have a version, but the // version script may assign a version anyway. std::string version; - if (this->version_script_.get_symbol_version(name, &version)) + bool is_global; + if (this->version_script_.get_symbol_version(name, &version, + &is_global)) { - // The version can be empty if the version script is - // only used to force some symbols to be local. - if (!version.empty()) + if (!is_global) + is_forced_local = true; + else if (!version.empty()) { ver = this->namepool_.add_with_length(version.c_str(), version.length(), true, &ver_key); - def = true; + is_default_version = true; } } - else if (this->version_script_.symbol_is_local(name)) - local = true; } } @@ -1244,9 +1323,10 @@ Symbol_table::add_from_pluginobj( Sized_symbol* res; res = this->add_from_object(obj, name, name_key, ver, ver_key, - def, *sym, st_shndx, true, st_shndx); + is_default_version, *sym, st_shndx, + is_ordinary, st_shndx); - if (local) + if (is_forced_local) this->force_local(res); return res; @@ -1265,7 +1345,7 @@ Symbol_table::add_from_dynobj( const unsigned char* versym, size_t versym_size, const std::vector* version_map, - typename Sized_relobj::Symbols* sympointers, + typename Sized_relobj_file::Symbols* sympointers, size_t* defined) { *defined = 0; @@ -1278,6 +1358,11 @@ Symbol_table::add_from_dynobj( return; } + // FIXME: For incremental links, we don't store version information, + // so we need to ignore version symbols for now. + if (parameters->incremental_update()) + versym = NULL; + if (versym != NULL && versym_size / 2 < count) { dynobj->error(_("too few symbol versions")); @@ -1421,10 +1506,11 @@ Symbol_table::add_from_dynobj( st_shndx); else { - const bool def = (!hidden - && st_shndx != elfcpp::SHN_UNDEF); + const bool is_default_version = + !hidden && st_shndx != elfcpp::SHN_UNDEF; res = this->add_from_object(dynobj, name, name_key, version, - version_key, def, *psym, st_shndx, + version_key, is_default_version, + *psym, st_shndx, is_ordinary, st_shndx); } } @@ -1446,6 +1532,37 @@ Symbol_table::add_from_dynobj( this->record_weak_aliases(&object_symbols); } +// Add a symbol from a incremental object file. + +template +Sized_symbol* +Symbol_table::add_from_incrobj( + Object* obj, + const char* name, + const char* ver, + elfcpp::Sym* sym) +{ + unsigned int st_shndx = sym->get_st_shndx(); + bool is_ordinary = st_shndx < elfcpp::SHN_LORESERVE; + + Stringpool::Key ver_key = 0; + bool is_default_version = false; + bool is_forced_local = false; + + Stringpool::Key name_key; + name = this->namepool_.add(name, true, &name_key); + + Sized_symbol* res; + res = this->add_from_object(obj, name, name_key, ver, ver_key, + is_default_version, *sym, st_shndx, + is_ordinary, st_shndx); + + if (is_forced_local) + this->force_local(res); + + return res; +} + // This is used to sort weak aliases. We sort them first by section // index, then by offset, then by weak ahead of strong. @@ -1543,9 +1660,10 @@ Sized_symbol* Symbol_table::define_special_symbol(const char** pname, const char** pversion, bool only_if_ref, Sized_symbol** poldsym, - bool *resolve_oldsym) + bool* resolve_oldsym) { *resolve_oldsym = false; + *poldsym = NULL; // If the caller didn't give us a version, see if we get one from // the version script. @@ -1553,14 +1671,16 @@ Symbol_table::define_special_symbol(const char** pname, const char** pversion, bool is_default_version = false; if (*pversion == NULL) { - if (this->version_script_.get_symbol_version(*pname, &v)) + bool is_global; + if (this->version_script_.get_symbol_version(*pname, &v, &is_global)) { - if (!v.empty()) - *pversion = v.c_str(); - - // If we get the version from a version script, then we are - // also the default version. - is_default_version = true; + if (is_global && !v.empty()) + { + *pversion = v.c_str(); + // If we get the version from a version script, then we + // are also the default version. + is_default_version = true; + } } } @@ -1581,7 +1701,9 @@ Symbol_table::define_special_symbol(const char** pname, const char** pversion, return NULL; *pname = oldsym->name(); - if (!is_default_version) + if (is_default_version) + *pversion = this->namepool_.add(*pversion, true, NULL); + else *pversion = oldsym->version(); } else @@ -1600,14 +1722,15 @@ Symbol_table::define_special_symbol(const char** pname, const char** pversion, version_key), snull)); - std::pair insdef = + std::pair insdefault = std::make_pair(this->table_.end(), false); if (is_default_version) { const Stringpool::Key vnull = 0; - insdef = this->table_.insert(std::make_pair(std::make_pair(name_key, - vnull), - snull)); + insdefault = + this->table_.insert(std::make_pair(std::make_pair(name_key, + vnull), + snull)); } if (!ins.second) @@ -1621,8 +1744,8 @@ Symbol_table::define_special_symbol(const char** pname, const char** pversion, Sized_symbol* soldsym = this->get_sized_symbol(oldsym); this->define_default_version(soldsym, - insdef.second, - insdef.first); + insdefault.second, + insdefault.first); } } else @@ -1633,11 +1756,11 @@ Symbol_table::define_special_symbol(const char** pname, const char** pversion, add_to_table = true; add_loc = ins.first; - if (is_default_version && !insdef.second) + if (is_default_version && !insdefault.second) { // We are adding NAME/VERSION, and it is the default // version. We already have an entry for NAME/NULL. - oldsym = insdef.first->second; + oldsym = insdefault.first->second; *resolve_oldsym = true; } else @@ -1647,7 +1770,7 @@ Symbol_table::define_special_symbol(const char** pname, const char** pversion, if (is_default_version) { add_def_to_table = true; - add_def_loc = insdef.first; + add_def_loc = insdefault.first; } } } @@ -1683,6 +1806,7 @@ Symbol_table::define_special_symbol(const char** pname, const char** pversion, Symbol* Symbol_table::define_in_output_data(const char* name, const char* version, + Defined defined, Output_data* od, uint64_t value, uint64_t symsize, @@ -1696,7 +1820,7 @@ Symbol_table::define_in_output_data(const char* name, if (parameters->target().get_size() == 32) { #if defined(HAVE_TARGET_32_LITTLE) || defined(HAVE_TARGET_32_BIG) - return this->do_define_in_output_data<32>(name, version, od, + return this->do_define_in_output_data<32>(name, version, defined, od, value, symsize, type, binding, visibility, nonvis, offset_is_from_end, @@ -1708,7 +1832,7 @@ Symbol_table::define_in_output_data(const char* name, else if (parameters->target().get_size() == 64) { #if defined(HAVE_TARGET_64_LITTLE) || defined(HAVE_TARGET_64_BIG) - return this->do_define_in_output_data<64>(name, version, od, + return this->do_define_in_output_data<64>(name, version, defined, od, value, symsize, type, binding, visibility, nonvis, offset_is_from_end, @@ -1728,6 +1852,7 @@ Sized_symbol* Symbol_table::do_define_in_output_data( const char* name, const char* version, + Defined defined, Output_data* od, typename elfcpp::Elf_types::Elf_Addr value, typename elfcpp::Elf_types::Elf_WXword symsize, @@ -1767,7 +1892,8 @@ Symbol_table::do_define_in_output_data( return NULL; sym->init_output_data(name, version, od, value, symsize, type, binding, - visibility, nonvis, offset_is_from_end); + visibility, nonvis, offset_is_from_end, + defined == PREDEFINED); if (oldsym == NULL) { @@ -1779,7 +1905,7 @@ Symbol_table::do_define_in_output_data( return sym; } - if (Symbol_table::should_override_with_special(oldsym)) + if (Symbol_table::should_override_with_special(oldsym, type, defined)) this->override_with_special(oldsym, sym); if (resolve_oldsym) @@ -1795,7 +1921,9 @@ Symbol_table::do_define_in_output_data( Symbol* Symbol_table::define_in_output_segment(const char* name, - const char* version, Output_segment* os, + const char* version, + Defined defined, + Output_segment* os, uint64_t value, uint64_t symsize, elfcpp::STT type, @@ -1808,7 +1936,7 @@ Symbol_table::define_in_output_segment(const char* name, if (parameters->target().get_size() == 32) { #if defined(HAVE_TARGET_32_LITTLE) || defined(HAVE_TARGET_32_BIG) - return this->do_define_in_output_segment<32>(name, version, os, + return this->do_define_in_output_segment<32>(name, version, defined, os, value, symsize, type, binding, visibility, nonvis, offset_base, only_if_ref); @@ -1819,7 +1947,7 @@ Symbol_table::define_in_output_segment(const char* name, else if (parameters->target().get_size() == 64) { #if defined(HAVE_TARGET_64_LITTLE) || defined(HAVE_TARGET_64_BIG) - return this->do_define_in_output_segment<64>(name, version, os, + return this->do_define_in_output_segment<64>(name, version, defined, os, value, symsize, type, binding, visibility, nonvis, offset_base, only_if_ref); @@ -1838,6 +1966,7 @@ Sized_symbol* Symbol_table::do_define_in_output_segment( const char* name, const char* version, + Defined defined, Output_segment* os, typename elfcpp::Elf_types::Elf_Addr value, typename elfcpp::Elf_types::Elf_WXword symsize, @@ -1877,7 +2006,8 @@ Symbol_table::do_define_in_output_segment( return NULL; sym->init_output_segment(name, version, os, value, symsize, type, binding, - visibility, nonvis, offset_base); + visibility, nonvis, offset_base, + defined == PREDEFINED); if (oldsym == NULL) { @@ -1889,7 +2019,7 @@ Symbol_table::do_define_in_output_segment( return sym; } - if (Symbol_table::should_override_with_special(oldsym)) + if (Symbol_table::should_override_with_special(oldsym, type, defined)) this->override_with_special(oldsym, sym); if (resolve_oldsym) @@ -1907,6 +2037,7 @@ Symbol_table::do_define_in_output_segment( Symbol* Symbol_table::define_as_constant(const char* name, const char* version, + Defined defined, uint64_t value, uint64_t symsize, elfcpp::STT type, @@ -1919,7 +2050,7 @@ Symbol_table::define_as_constant(const char* name, if (parameters->target().get_size() == 32) { #if defined(HAVE_TARGET_32_LITTLE) || defined(HAVE_TARGET_32_BIG) - return this->do_define_as_constant<32>(name, version, value, + return this->do_define_as_constant<32>(name, version, defined, value, symsize, type, binding, visibility, nonvis, only_if_ref, force_override); @@ -1930,7 +2061,7 @@ Symbol_table::define_as_constant(const char* name, else if (parameters->target().get_size() == 64) { #if defined(HAVE_TARGET_64_LITTLE) || defined(HAVE_TARGET_64_BIG) - return this->do_define_as_constant<64>(name, version, value, + return this->do_define_as_constant<64>(name, version, defined, value, symsize, type, binding, visibility, nonvis, only_if_ref, force_override); @@ -1949,6 +2080,7 @@ Sized_symbol* Symbol_table::do_define_as_constant( const char* name, const char* version, + Defined defined, typename elfcpp::Elf_types::Elf_Addr value, typename elfcpp::Elf_types::Elf_WXword symsize, elfcpp::STT type, @@ -1987,7 +2119,7 @@ Symbol_table::do_define_as_constant( return NULL; sym->init_constant(name, version, value, symsize, type, binding, visibility, - nonvis); + nonvis, defined == PREDEFINED); if (oldsym == NULL) { @@ -2005,7 +2137,8 @@ Symbol_table::do_define_as_constant( return sym; } - if (force_override || Symbol_table::should_override_with_special(oldsym)) + if (force_override + || Symbol_table::should_override_with_special(oldsym, type, defined)) this->override_with_special(oldsym, sym); if (resolve_oldsym) @@ -2028,14 +2161,14 @@ Symbol_table::define_symbols(const Layout* layout, int count, { Output_section* os = layout->find_output_section(p->output_section); if (os != NULL) - this->define_in_output_data(p->name, NULL, os, p->value, + this->define_in_output_data(p->name, NULL, PREDEFINED, os, p->value, p->size, p->type, p->binding, p->visibility, p->nonvis, p->offset_is_from_end, only_if_ref || p->only_if_ref); else - this->define_as_constant(p->name, NULL, 0, p->size, p->type, - p->binding, p->visibility, p->nonvis, + this->define_as_constant(p->name, NULL, PREDEFINED, 0, p->size, + p->type, p->binding, p->visibility, p->nonvis, only_if_ref || p->only_if_ref, false); } @@ -2054,14 +2187,14 @@ Symbol_table::define_symbols(const Layout* layout, int count, p->segment_flags_set, p->segment_flags_clear); if (os != NULL) - this->define_in_output_segment(p->name, NULL, os, p->value, + this->define_in_output_segment(p->name, NULL, PREDEFINED, os, p->value, p->size, p->type, p->binding, p->visibility, p->nonvis, p->offset_base, only_if_ref || p->only_if_ref); else - this->define_as_constant(p->name, NULL, 0, p->size, p->type, - p->binding, p->visibility, p->nonvis, + this->define_as_constant(p->name, NULL, PREDEFINED, 0, p->size, + p->type, p->binding, p->visibility, p->nonvis, only_if_ref || p->only_if_ref, false); } @@ -2090,7 +2223,7 @@ Symbol_table::define_with_copy_reloc( if (binding == elfcpp::STB_WEAK) binding = elfcpp::STB_GLOBAL; - this->define_in_output_data(csym->name(), csym->version(), + this->define_in_output_data(csym->name(), csym->version(), COPY, posd, value, csym->symsize(), csym->type(), binding, csym->visibility(), csym->nonvis(), @@ -2135,14 +2268,15 @@ Symbol_table::get_copy_source(const Symbol* sym) const // Add any undefined symbols named on the command line. void -Symbol_table::add_undefined_symbols_from_command_line() +Symbol_table::add_undefined_symbols_from_command_line(Layout* layout) { - if (parameters->options().any_undefined()) + if (parameters->options().any_undefined() + || layout->script_options()->any_unreferenced()) { if (parameters->target().get_size() == 32) { #if defined(HAVE_TARGET_32_LITTLE) || defined(HAVE_TARGET_32_BIG) - this->do_add_undefined_symbols_from_command_line<32>(); + this->do_add_undefined_symbols_from_command_line<32>(layout); #else gold_unreachable(); #endif @@ -2150,7 +2284,7 @@ Symbol_table::add_undefined_symbols_from_command_line() else if (parameters->target().get_size() == 64) { #if defined(HAVE_TARGET_64_LITTLE) || defined(HAVE_TARGET_64_BIG) - this->do_add_undefined_symbols_from_command_line<64>(); + this->do_add_undefined_symbols_from_command_line<64>(layout); #else gold_unreachable(); #endif @@ -2162,50 +2296,65 @@ Symbol_table::add_undefined_symbols_from_command_line() template void -Symbol_table::do_add_undefined_symbols_from_command_line() +Symbol_table::do_add_undefined_symbols_from_command_line(Layout* layout) { for (options::String_set::const_iterator p = parameters->options().undefined_begin(); p != parameters->options().undefined_end(); ++p) - { - const char* name = p->c_str(); + this->add_undefined_symbol_from_command_line(p->c_str()); - if (this->lookup(name) != NULL) - continue; + for (options::String_set::const_iterator p = + parameters->options().export_dynamic_symbol_begin(); + p != parameters->options().export_dynamic_symbol_end(); + ++p) + this->add_undefined_symbol_from_command_line(p->c_str()); - const char* version = NULL; + for (Script_options::referenced_const_iterator p = + layout->script_options()->referenced_begin(); + p != layout->script_options()->referenced_end(); + ++p) + this->add_undefined_symbol_from_command_line(p->c_str()); +} - Sized_symbol* sym; - Sized_symbol* oldsym; - bool resolve_oldsym; - if (parameters->target().is_big_endian()) - { +template +void +Symbol_table::add_undefined_symbol_from_command_line(const char* name) +{ + if (this->lookup(name) != NULL) + return; + + const char* version = NULL; + + Sized_symbol* sym; + Sized_symbol* oldsym; + bool resolve_oldsym; + if (parameters->target().is_big_endian()) + { #if defined(HAVE_TARGET_32_BIG) || defined(HAVE_TARGET_64_BIG) - sym = this->define_special_symbol(&name, &version, - false, &oldsym, - &resolve_oldsym); + sym = this->define_special_symbol(&name, &version, + false, &oldsym, + &resolve_oldsym); #else - gold_unreachable(); + gold_unreachable(); #endif - } - else - { + } + else + { #if defined(HAVE_TARGET_32_LITTLE) || defined(HAVE_TARGET_64_LITTLE) - sym = this->define_special_symbol(&name, &version, - false, &oldsym, - &resolve_oldsym); + sym = this->define_special_symbol(&name, &version, + false, &oldsym, + &resolve_oldsym); #else - gold_unreachable(); + gold_unreachable(); #endif - } + } - gold_assert(oldsym == NULL); + gold_assert(oldsym == NULL); - sym->init_undefined(name, version, elfcpp::STT_NOTYPE, elfcpp::STB_GLOBAL, - elfcpp::STV_DEFAULT, 0); - ++this->saw_undefined_; - } + sym->init_undefined(name, version, elfcpp::STT_NOTYPE, elfcpp::STB_GLOBAL, + elfcpp::STV_DEFAULT, 0); + ++this->saw_undefined_; } // Set the dynamic symbol indexes. INDEX is the index of the first @@ -2219,6 +2368,8 @@ Symbol_table::set_dynsym_indexes(unsigned int index, Stringpool* dynpool, Versions* versions) { + std::vector as_needed_sym; + for (Symbol_table_type::iterator p = this->table_.begin(); p != this->table_.end(); ++p) @@ -2229,7 +2380,7 @@ Symbol_table::set_dynsym_indexes(unsigned int index, // some symbols appear more than once in the symbol table, with // and without a version. - if (!sym->should_add_dynsym_entry()) + if (!sym->should_add_dynsym_entry(this)) sym->set_dynsym_index(-1U); else if (!sym->has_dynsym_index()) { @@ -2238,12 +2389,43 @@ Symbol_table::set_dynsym_indexes(unsigned int index, syms->push_back(sym); dynpool->add(sym->name(), false, NULL); - // Record any version information. - if (sym->version() != NULL) - versions->record_version(this, dynpool, sym); + // If the symbol is defined in a dynamic object and is + // referenced strongly in a regular object, then mark the + // dynamic object as needed. This is used to implement + // --as-needed. + if (sym->is_from_dynobj() + && sym->in_reg() + && !sym->is_undef_binding_weak()) + sym->object()->set_is_needed(); + + // Record any version information, except those from + // as-needed libraries not seen to be needed. Note that the + // is_needed state for such libraries can change in this loop. + if (sym->version() != NULL) + { + if (!sym->is_from_dynobj() + || !sym->object()->as_needed() + || sym->object()->is_needed()) + versions->record_version(this, dynpool, sym); + else + as_needed_sym.push_back(sym); + } } } + // Process version information for symbols from as-needed libraries. + for (std::vector::iterator p = as_needed_sym.begin(); + p != as_needed_sym.end(); + ++p) + { + Symbol* sym = *p; + + if (sym->object()->is_needed()) + versions->record_version(this, dynpool, sym); + else + sym->clear_version(); + } + // Finish up the versions. In some cases this may add new dynamic // symbols. index = versions->finalize(this, index, syms); @@ -2259,7 +2441,7 @@ Symbol_table::set_dynsym_indexes(unsigned int index, off_t Symbol_table::finalize(off_t off, off_t dynoff, size_t dyn_global_index, size_t dyncount, Stringpool* pool, - unsigned int *plocal_symcount) + unsigned int* plocal_symcount) { off_t ret; @@ -2305,7 +2487,10 @@ Symbol_table::add_to_final_symtab(Symbol* sym, Stringpool* pool, unsigned int* pindex, off_t* poff) { sym->set_symtab_index(*pindex); - pool->add(sym->name(), false, NULL); + if (sym->version() == NULL || !parameters->options().relocatable()) + pool->add(sym->name(), false, NULL); + else + pool->add(sym->versioned_name(), true, NULL); ++*pindex; *poff += elfcpp::Elf_sizes::sym_size; } @@ -2404,7 +2589,6 @@ Symbol_table::compute_final_value( { Relobj* relobj = static_cast(symobj); Output_section* os = relobj->output_section(shndx); - uint64_t secoff64 = relobj->output_section_offset(shndx); if (this->is_section_folded(relobj, shndx)) { @@ -2414,11 +2598,17 @@ Symbol_table::compute_final_value( shndx); gold_assert(folded.first != NULL); Relobj* folded_obj = reinterpret_cast(folded.first); - os = folded_obj->output_section(folded.second); + unsigned folded_shndx = folded.second; + + os = folded_obj->output_section(folded_shndx); gold_assert(os != NULL); - secoff64 = folded_obj->output_section_offset(folded.second); + + // Replace (relobj, shndx) with canonical ICF input section. + shndx = folded_shndx; + relobj = folded_obj; } + uint64_t secoff64 = relobj->output_section_offset(shndx); if (os == NULL) { bool static_or_reloc = (parameters->doing_static_link() || @@ -2527,6 +2717,15 @@ Symbol_table::sized_finalize_symbol(Symbol* unsized_sym) return false; } + // If the symbol is only present on plugin files, the plugin decided we + // don't need it. + if (!sym->in_real_elf()) + { + gold_assert(!sym->has_symtab_index()); + sym->set_symtab_index(-1U); + return false; + } + // Compute final symbol value. Compute_final_value_status status; Value_type value = this->compute_final_value(sym, &status); @@ -2660,6 +2859,13 @@ Symbol_table::sized_write_globals(const Stringpool* sympool, unsigned int shndx; typename elfcpp::Elf_types::Elf_Addr sym_value = sym->value(); typename elfcpp::Elf_types::Elf_Addr dynsym_value = sym_value; + elfcpp::STB binding = sym->binding(); + + // If --no-gnu-unique is set, change STB_GNU_UNIQUE to STB_GLOBAL. + if (binding == elfcpp::STB_GNU_UNIQUE + && !parameters->options().gnu_unique()) + binding = elfcpp::STB_GLOBAL; + switch (sym->source()) { case Symbol::FROM_OBJECT: @@ -2683,6 +2889,10 @@ Symbol_table::sized_write_globals(const Stringpool* sympool, if (sym->needs_dynsym_value()) dynsym_value = target.dynsym_value(sym); shndx = elfcpp::SHN_UNDEF; + if (sym->is_undef_binding_weak()) + binding = elfcpp::STB_WEAK; + else + binding = elfcpp::STB_GLOBAL; } else if (symobj->pluginobj() != NULL) shndx = elfcpp::SHN_UNDEF; @@ -2730,15 +2940,24 @@ Symbol_table::sized_write_globals(const Stringpool* sympool, break; case Symbol::IN_OUTPUT_DATA: - shndx = sym->output_data()->out_shndx(); - if (shndx >= elfcpp::SHN_LORESERVE) - { - if (sym_index != -1U) - symtab_xindex->add(sym_index, shndx); - if (dynsym_index != -1U) - dynsym_xindex->add(dynsym_index, shndx); - shndx = elfcpp::SHN_XINDEX; - } + { + Output_data* od = sym->output_data(); + + shndx = od->out_shndx(); + if (shndx >= elfcpp::SHN_LORESERVE) + { + if (sym_index != -1U) + symtab_xindex->add(sym_index, shndx); + if (dynsym_index != -1U) + dynsym_xindex->add(dynsym_index, shndx); + shndx = elfcpp::SHN_XINDEX; + } + + // In object files symbol values are section + // relative. + if (parameters->options().relocatable()) + sym_value -= od->address(); + } break; case Symbol::IN_OUTPUT_SEGMENT: @@ -2763,7 +2982,7 @@ Symbol_table::sized_write_globals(const Stringpool* sympool, gold_assert(sym_index < output_count); unsigned char* ps = psyms + (sym_index * sym_size); this->sized_write_symbol(sym, sym_value, shndx, - sympool, ps); + binding, sympool, ps); } if (dynsym_index != -1U) @@ -2772,7 +2991,7 @@ Symbol_table::sized_write_globals(const Stringpool* sympool, gold_assert(dynsym_index < dynamic_count); unsigned char* pd = dynamic_view + (dynsym_index * sym_size); this->sized_write_symbol(sym, dynsym_value, shndx, - dynpool, pd); + binding, dynpool, pd); } } @@ -2790,22 +3009,31 @@ Symbol_table::sized_write_symbol( Sized_symbol* sym, typename elfcpp::Elf_types::Elf_Addr value, unsigned int shndx, + elfcpp::STB binding, const Stringpool* pool, unsigned char* p) const { elfcpp::Sym_write osym(p); - osym.put_st_name(pool->get_offset(sym->name())); + if (sym->version() == NULL || !parameters->options().relocatable()) + osym.put_st_name(pool->get_offset(sym->name())); + else + osym.put_st_name(pool->get_offset(sym->versioned_name())); osym.put_st_value(value); // Use a symbol size of zero for undefined symbols from shared libraries. if (shndx == elfcpp::SHN_UNDEF && sym->is_from_dynobj()) osym.put_st_size(0); else osym.put_st_size(sym->symsize()); + elfcpp::STT type = sym->type(); + // Turn IFUNC symbols from shared libraries into normal FUNC symbols. + if (type == elfcpp::STT_GNU_IFUNC + && sym->is_from_dynobj()) + type = elfcpp::STT_FUNC; // A version script may have overridden the default binding. if (sym->is_forced_local()) - osym.put_st_info(elfcpp::elf_st_info(elfcpp::STB_LOCAL, sym->type())); + osym.put_st_info(elfcpp::elf_st_info(elfcpp::STB_LOCAL, type)); else - osym.put_st_info(elfcpp::elf_st_info(sym->binding(), sym->type())); + osym.put_st_info(elfcpp::elf_st_info(binding, type)); osym.put_st_other(elfcpp::elf_st_other(sym->visibility(), sym->nonvis())); osym.put_st_shndx(shndx); } @@ -2846,7 +3074,7 @@ Symbol_table::warn_about_undefined_dynobj_symbol(Symbol* sym) const // Write out a section symbol. Return the update offset. void -Symbol_table::write_section_symbol(const Output_section *os, +Symbol_table::write_section_symbol(const Output_section* os, Output_symtab_xindex* symtab_xindex, Output_file* of, off_t offset) const @@ -2934,34 +3162,97 @@ Symbol_table::print_stats() const // We check for ODR violations by looking for symbols with the same // name for which the debugging information reports that they were -// defined in different source locations. When comparing the source -// location, we consider instances with the same base filename and -// line number to be the same. This is because different object -// files/shared libraries can include the same header file using -// different paths, and we don't want to report an ODR violation in -// that case. +// defined in disjoint source locations. When comparing the source +// location, we consider instances with the same base filename to be +// the same. This is because different object files/shared libraries +// can include the same header file using different paths, and +// different optimization settings can make the line number appear to +// be a couple lines off, and we don't want to report an ODR violation +// in those cases. // This struct is used to compare line information, as returned by // Dwarf_line_info::one_addr2line. It implements a < comparison -// operator used with std::set. +// operator used with std::sort. struct Odr_violation_compare { bool operator()(const std::string& s1, const std::string& s2) const { - std::string::size_type pos1 = s1.rfind('/'); - std::string::size_type pos2 = s2.rfind('/'); - if (pos1 == std::string::npos - || pos2 == std::string::npos) - return s1 < s2; - return s1.compare(pos1, std::string::npos, - s2, pos2, std::string::npos) < 0; + // Inputs should be of the form "dirname/filename:linenum" where + // "dirname/" is optional. We want to compare just the filename:linenum. + + // Find the last '/' in each string. + std::string::size_type s1begin = s1.rfind('/'); + std::string::size_type s2begin = s2.rfind('/'); + // If there was no '/' in a string, start at the beginning. + if (s1begin == std::string::npos) + s1begin = 0; + if (s2begin == std::string::npos) + s2begin = 0; + return s1.compare(s1begin, std::string::npos, + s2, s2begin, std::string::npos) < 0; } }; +// Returns all of the lines attached to LOC, not just the one the +// instruction actually came from. +std::vector +Symbol_table::linenos_from_loc(const Task* task, + const Symbol_location& loc) +{ + // We need to lock the object in order to read it. This + // means that we have to run in a singleton Task. If we + // want to run this in a general Task for better + // performance, we will need one Task for object, plus + // appropriate locking to ensure that we don't conflict with + // other uses of the object. Also note, one_addr2line is not + // currently thread-safe. + Task_lock_obj tl(task, loc.object); + + std::vector result; + Symbol_location code_loc = loc; + parameters->target().function_location(&code_loc); + // 16 is the size of the object-cache that one_addr2line should use. + std::string canonical_result = Dwarf_line_info::one_addr2line( + code_loc.object, code_loc.shndx, code_loc.offset, 16, &result); + if (!canonical_result.empty()) + result.push_back(canonical_result); + return result; +} + +// OutputIterator that records if it was ever assigned to. This +// allows it to be used with std::set_intersection() to check for +// intersection rather than computing the intersection. +struct Check_intersection +{ + Check_intersection() + : value_(false) + {} + + bool had_intersection() const + { return this->value_; } + + Check_intersection& operator++() + { return *this; } + + Check_intersection& operator*() + { return *this; } + + template + Check_intersection& operator=(const T&) + { + this->value_ = true; + return *this; + } + + private: + bool value_; +}; + // Check candidate_odr_violations_ to find symbols with the same name -// but apparently different definitions (different source-file/line-no). +// but apparently different definitions (different source-file/line-no +// for each line assigned to the first instruction). void Symbol_table::detect_odr_violations(const Task* task, @@ -2971,39 +3262,73 @@ Symbol_table::detect_odr_violations(const Task* task, it != candidate_odr_violations_.end(); ++it) { - const char* symbol_name = it->first; - // We use a sorted set so the output is deterministic. - std::set line_nums; + const char* const symbol_name = it->first; + + std::string first_object_name; + std::vector first_object_linenos; - for (Unordered_set::const_iterator - locs = it->second.begin(); - locs != it->second.end(); - ++locs) + Unordered_set::const_iterator + locs = it->second.begin(); + const Unordered_set::const_iterator + locs_end = it->second.end(); + for (; locs != locs_end && first_object_linenos.empty(); ++locs) { - // We need to lock the object in order to read it. This - // means that we have to run in a singleton Task. If we - // want to run this in a general Task for better - // performance, we will need one Task for object, plus - // appropriate locking to ensure that we don't conflict with - // other uses of the object. Also note, one_addr2line is not - // currently thread-safe. - Task_lock_obj tl(task, locs->object); - // 16 is the size of the object-cache that one_addr2line should use. - std::string lineno = Dwarf_line_info::one_addr2line( - locs->object, locs->shndx, locs->offset, 16); - if (!lineno.empty()) - line_nums.insert(lineno); + // Save the line numbers from the first definition to + // compare to the other definitions. Ideally, we'd compare + // every definition to every other, but we don't want to + // take O(N^2) time to do this. This shortcut may cause + // false negatives that appear or disappear depending on the + // link order, but it won't cause false positives. + first_object_name = locs->object->name(); + first_object_linenos = this->linenos_from_loc(task, *locs); } - if (line_nums.size() > 1) + // Sort by Odr_violation_compare to make std::set_intersection work. + std::sort(first_object_linenos.begin(), first_object_linenos.end(), + Odr_violation_compare()); + + for (; locs != locs_end; ++locs) { - gold_warning(_("while linking %s: symbol '%s' defined in multiple " - "places (possible ODR violation):"), - output_file_name, demangle(symbol_name).c_str()); - for (std::set::const_iterator it2 = line_nums.begin(); - it2 != line_nums.end(); - ++it2) - fprintf(stderr, " %s\n", it2->c_str()); + std::vector linenos = + this->linenos_from_loc(task, *locs); + // linenos will be empty if we couldn't parse the debug info. + if (linenos.empty()) + continue; + // Sort by Odr_violation_compare to make std::set_intersection work. + std::sort(linenos.begin(), linenos.end(), Odr_violation_compare()); + + Check_intersection intersection_result = + std::set_intersection(first_object_linenos.begin(), + first_object_linenos.end(), + linenos.begin(), + linenos.end(), + Check_intersection(), + Odr_violation_compare()); + if (!intersection_result.had_intersection()) + { + gold_warning(_("while linking %s: symbol '%s' defined in " + "multiple places (possible ODR violation):"), + output_file_name, demangle(symbol_name).c_str()); + // This only prints one location from each definition, + // which may not be the location we expect to intersect + // with another definition. We could print the whole + // set of locations, but that seems too verbose. + gold_assert(!first_object_linenos.empty()); + gold_assert(!linenos.empty()); + fprintf(stderr, _(" %s from %s\n"), + first_object_linenos[0].c_str(), + first_object_name.c_str()); + fprintf(stderr, _(" %s from %s\n"), + linenos[0].c_str(), + locs->object->name().c_str()); + // Only print one broken pair, to avoid needing to + // compare against a list of the disjoint definition + // locations we've found so far. (If we kept comparing + // against just the first one, we'd get a lot of + // redundant complaints about the second definition + // location.) + break; + } } } // We only call one_addr2line() in this function, so we can clear its cache. @@ -3051,6 +3376,12 @@ Warnings::issue_warning(const Symbol* sym, size_t relnum, off_t reloffset) const { gold_assert(sym->has_warning()); + + // We don't want to issue a warning for a relocation against the + // symbol in the same object file in which the symbol is defined. + if (sym->object() == relinfo->object) + return; + Warning_table::const_iterator p = this->warnings_.find(sym->name()); gold_assert(p != this->warnings_.end()); gold_warning_at_location(relinfo, relnum, reloffset, @@ -3077,13 +3408,13 @@ Sized_symbol<64>::allocate_common(Output_data*, Value_type); template void Symbol_table::add_from_relobj<32, false>( - Sized_relobj<32, false>* relobj, + Sized_relobj_file<32, false>* relobj, const unsigned char* syms, size_t count, size_t symndx_offset, const char* sym_names, size_t sym_name_size, - Sized_relobj<32, false>::Symbols* sympointers, + Sized_relobj_file<32, false>::Symbols* sympointers, size_t* defined); #endif @@ -3091,13 +3422,13 @@ Symbol_table::add_from_relobj<32, false>( template void Symbol_table::add_from_relobj<32, true>( - Sized_relobj<32, true>* relobj, + Sized_relobj_file<32, true>* relobj, const unsigned char* syms, size_t count, size_t symndx_offset, const char* sym_names, size_t sym_name_size, - Sized_relobj<32, true>::Symbols* sympointers, + Sized_relobj_file<32, true>::Symbols* sympointers, size_t* defined); #endif @@ -3105,13 +3436,13 @@ Symbol_table::add_from_relobj<32, true>( template void Symbol_table::add_from_relobj<64, false>( - Sized_relobj<64, false>* relobj, + Sized_relobj_file<64, false>* relobj, const unsigned char* syms, size_t count, size_t symndx_offset, const char* sym_names, size_t sym_name_size, - Sized_relobj<64, false>::Symbols* sympointers, + Sized_relobj_file<64, false>::Symbols* sympointers, size_t* defined); #endif @@ -3119,13 +3450,13 @@ Symbol_table::add_from_relobj<64, false>( template void Symbol_table::add_from_relobj<64, true>( - Sized_relobj<64, true>* relobj, + Sized_relobj_file<64, true>* relobj, const unsigned char* syms, size_t count, size_t symndx_offset, const char* sym_names, size_t sym_name_size, - Sized_relobj<64, true>::Symbols* sympointers, + Sized_relobj_file<64, true>::Symbols* sympointers, size_t* defined); #endif @@ -3181,7 +3512,7 @@ Symbol_table::add_from_dynobj<32, false>( const unsigned char* versym, size_t versym_size, const std::vector* version_map, - Sized_relobj<32, false>::Symbols* sympointers, + Sized_relobj_file<32, false>::Symbols* sympointers, size_t* defined); #endif @@ -3197,7 +3528,7 @@ Symbol_table::add_from_dynobj<32, true>( const unsigned char* versym, size_t versym_size, const std::vector* version_map, - Sized_relobj<32, true>::Symbols* sympointers, + Sized_relobj_file<32, true>::Symbols* sympointers, size_t* defined); #endif @@ -3213,7 +3544,7 @@ Symbol_table::add_from_dynobj<64, false>( const unsigned char* versym, size_t versym_size, const std::vector* version_map, - Sized_relobj<64, false>::Symbols* sympointers, + Sized_relobj_file<64, false>::Symbols* sympointers, size_t* defined); #endif @@ -3229,10 +3560,50 @@ Symbol_table::add_from_dynobj<64, true>( const unsigned char* versym, size_t versym_size, const std::vector* version_map, - Sized_relobj<64, true>::Symbols* sympointers, + Sized_relobj_file<64, true>::Symbols* sympointers, size_t* defined); #endif +#ifdef HAVE_TARGET_32_LITTLE +template +Sized_symbol<32>* +Symbol_table::add_from_incrobj( + Object* obj, + const char* name, + const char* ver, + elfcpp::Sym<32, false>* sym); +#endif + +#ifdef HAVE_TARGET_32_BIG +template +Sized_symbol<32>* +Symbol_table::add_from_incrobj( + Object* obj, + const char* name, + const char* ver, + elfcpp::Sym<32, true>* sym); +#endif + +#ifdef HAVE_TARGET_64_LITTLE +template +Sized_symbol<64>* +Symbol_table::add_from_incrobj( + Object* obj, + const char* name, + const char* ver, + elfcpp::Sym<64, false>* sym); +#endif + +#ifdef HAVE_TARGET_64_BIG +template +Sized_symbol<64>* +Symbol_table::add_from_incrobj( + Object* obj, + const char* name, + const char* ver, + elfcpp::Sym<64, true>* sym); +#endif + #if defined(HAVE_TARGET_32_LITTLE) || defined(HAVE_TARGET_32_BIG) template void