X-Git-Url: http://drtracing.org/?a=blobdiff_plain;f=gold%2Fresolve.cc;h=a425dc9c30d4ff3b796a56e15cc917f5291b8015;hb=2da4b788f7a80ed9589d0e8856584e9dfa2813ff;hp=291bca6967337a637fdd858e76019e87caa3afb0;hpb=f3e9c5c5170afd576cb1c31464472587aba05f52;p=deliverable%2Fbinutils-gdb.git diff --git a/gold/resolve.cc b/gold/resolve.cc index 291bca6967..a425dc9c30 100644 --- a/gold/resolve.cc +++ b/gold/resolve.cc @@ -1,6 +1,6 @@ // resolve.cc -- symbol resolution for gold -// Copyright 2006, 2007, 2008 Free Software Foundation, Inc. +// Copyright (C) 2006-2020 Free Software Foundation, Inc. // Written by Ian Lance Taylor . // This file is part of gold. @@ -26,12 +26,63 @@ #include "target.h" #include "object.h" #include "symtab.h" +#include "plugin.h" namespace gold { // Symbol methods used in this file. +// This symbol is being overridden by another symbol whose version is +// VERSION. Update the VERSION_ field accordingly. + +inline void +Symbol::override_version(const char* version) +{ + if (version == NULL) + { + // This is the case where this symbol is NAME/VERSION, and the + // version was not marked as hidden. That makes it the default + // version, so we create NAME/NULL. Later we see another symbol + // NAME/NULL, and that symbol is overriding this one. In this + // case, since NAME/VERSION is the default, we make NAME/NULL + // override NAME/VERSION as well. They are already the same + // Symbol structure. Setting the VERSION_ field to NULL ensures + // that it will be output with the correct, empty, version. + this->version_ = version; + } + else + { + // This is the case where this symbol is NAME/VERSION_ONE, and + // now we see NAME/VERSION_TWO, and NAME/VERSION_TWO is + // overriding NAME. If VERSION_ONE and VERSION_TWO are + // different, then this can only happen when VERSION_ONE is NULL + // and VERSION_TWO is not hidden. + gold_assert(this->version_ == version || this->version_ == NULL); + this->version_ = version; + } +} + +// This symbol is being overidden by another symbol whose visibility +// is VISIBILITY. Updated the VISIBILITY_ field accordingly. + +inline void +Symbol::override_visibility(elfcpp::STV visibility) +{ + // The rule for combining visibility is that we always choose the + // most constrained visibility. In order of increasing constraint, + // visibility goes PROTECTED, HIDDEN, INTERNAL. This is the reverse + // of the numeric values, so the effect is that we always want the + // smallest non-zero value. + if (visibility != elfcpp::STV_DEFAULT) + { + if (this->visibility_ == elfcpp::STV_DEFAULT) + this->visibility_ = visibility; + else if (this->visibility_ > visibility) + this->visibility_ = visibility; + } +} + // Override the fields in Symbol. template @@ -41,17 +92,15 @@ Symbol::override_base(const elfcpp::Sym& sym, Object* object, const char* version) { gold_assert(this->source_ == FROM_OBJECT); - this->u_.from_object.object = object; - if (version != NULL && this->version() != version) - { - gold_assert(this->version() == NULL); - this->version_ = version; - } - this->u_.from_object.shndx = st_shndx; + this->u1_.object = object; + this->override_version(version); + this->u2_.shndx = st_shndx; this->is_ordinary_shndx_ = is_ordinary; - this->type_ = sym.get_st_type(); + // Don't override st_type from plugin placeholder symbols. + if (object->pluginobj() == NULL) + this->type_ = sym.get_st_type(); this->binding_ = sym.get_st_bind(); - this->visibility_ = sym.get_st_visibility(); + this->override_visibility(sym.get_st_visibility()); this->nonvis_ = sym.get_st_nonvis(); if (object->is_dynamic()) this->in_dyn_ = true; @@ -124,13 +173,14 @@ static const unsigned int common_flag = 2 << def_undef_or_common_shift; static unsigned int symbol_to_bits(elfcpp::STB binding, bool is_dynamic, - unsigned int shndx, bool is_ordinary, elfcpp::STT type) + unsigned int shndx, bool is_ordinary) { unsigned int bits; switch (binding) { case elfcpp::STB_GLOBAL: + case elfcpp::STB_GNU_UNIQUE: bits = global_flag; break; @@ -143,11 +193,12 @@ symbol_to_bits(elfcpp::STB binding, bool is_dynamic, // table. gold_error(_("invalid STB_LOCAL symbol in external symbols")); bits = global_flag; + break; default: // Any target which wants to handle STB_LOOS, etc., needs to // define a resolve method. - gold_error(_("unsupported symbol binding")); + gold_error(_("unsupported symbol binding %d"), static_cast(binding)); bits = global_flag; } @@ -168,7 +219,7 @@ symbol_to_bits(elfcpp::STB binding, bool is_dynamic, break; default: - if (type == elfcpp::STT_COMMON) + if (!is_ordinary && Symbol::is_common_shndx(shndx)) bits |= common_flag; else bits |= def_flag; @@ -184,7 +235,7 @@ symbol_to_bits(elfcpp::STB binding, bool is_dynamic, // IS_ORDINARY is whether ST_SHNDX is a normal section index rather // than a special code. ORIG_ST_SHNDX is the original section index, // before any munging because of discarded sections, except that all -// non-ordinary section indexes are mapped to SHN_UNDEF. VERSION of +// non-ordinary section indexes are mapped to SHN_UNDEF. VERSION is // the version of SYM. template @@ -193,63 +244,124 @@ Symbol_table::resolve(Sized_symbol* to, const elfcpp::Sym& sym, unsigned int st_shndx, bool is_ordinary, unsigned int orig_st_shndx, - Object* object, const char* version) + Object* object, const char* version, + bool is_default_version) { - if (object->target()->has_resolve()) + bool to_is_ordinary; + const unsigned int to_shndx = to->shndx(&to_is_ordinary); + + // It's possible for a symbol to be defined in an object file + // using .symver to give it a version, and for there to also be + // a linker script giving that symbol the same version. We + // don't want to give a multiple-definition error for this + // harmless redefinition. + if (to->source() == Symbol::FROM_OBJECT + && to->object() == object + && to->is_defined() + && is_ordinary + && to_is_ordinary + && to_shndx == st_shndx + && to->value() == sym.get_st_value()) + return; + + // Likewise for an absolute symbol defined twice with the same value. + if (!is_ordinary + && st_shndx == elfcpp::SHN_ABS + && !to_is_ordinary + && to_shndx == elfcpp::SHN_ABS + && to->value() == sym.get_st_value()) + return; + + if (parameters->target().has_resolve()) { Sized_target* sized_target; - sized_target = object->sized_target(); - sized_target->resolve(to, sym, object, version); - return; + sized_target = parameters->sized_target(); + if (sized_target->resolve(to, sym, object, version)) + return; } if (!object->is_dynamic()) { + if (sym.get_st_type() == elfcpp::STT_COMMON + && (is_ordinary || !Symbol::is_common_shndx(st_shndx))) + { + gold_warning(_("STT_COMMON symbol '%s' in %s " + "is not in a common section"), + to->demangled_name().c_str(), + to->object()->name().c_str()); + return; + } // Record that we've seen this symbol in a regular object. to->set_in_reg(); } + else if (st_shndx == elfcpp::SHN_UNDEF + && (to->visibility() == elfcpp::STV_HIDDEN + || to->visibility() == elfcpp::STV_INTERNAL)) + { + // The symbol is hidden, so a reference from a shared object + // cannot bind to it. We tried issuing a warning in this case, + // but that produces false positives when the symbol is + // actually resolved in a different shared object (PR 15574). + return; + } else { // Record that we've seen this symbol in a dynamic object. to->set_in_dyn(); } - unsigned int frombits = symbol_to_bits(sym.get_st_bind(), - object->is_dynamic(), - st_shndx, is_ordinary, - sym.get_st_type()); - - bool adjust_common_sizes; - if (Symbol_table::should_override(to, frombits, object, - &adjust_common_sizes)) - { - typename Sized_symbol::Size_type tosize = to->symsize(); - - this->override(to, sym, st_shndx, is_ordinary, object, version); + // Record if we've seen this symbol in a real ELF object (i.e., the + // symbol is referenced from outside the world known to the plugin). + if (object->pluginobj() == NULL && !object->is_dynamic()) + to->set_in_real_elf(); - if (adjust_common_sizes && tosize > to->symsize()) - to->set_symsize(tosize); - } - else + // If we're processing replacement files, allow new symbols to override + // the placeholders from the plugin objects. + // Treat common symbols specially since it is possible that an ELF + // file increased the size of the alignment. + if (to->source() == Symbol::FROM_OBJECT) { - if (adjust_common_sizes && sym.get_st_size() > to->symsize()) - to->set_symsize(sym.get_st_size()); + Pluginobj* obj = to->object()->pluginobj(); + if (obj != NULL + && parameters->options().plugins()->in_replacement_phase()) + { + bool adjust_common = false; + typename Sized_symbol::Size_type tosize = 0; + typename Sized_symbol::Value_type tovalue = 0; + if (to->is_common() + && !is_ordinary && Symbol::is_common_shndx(st_shndx)) + { + adjust_common = true; + tosize = to->symsize(); + tovalue = to->value(); + } + this->override(to, sym, st_shndx, is_ordinary, object, version); + if (adjust_common) + { + if (tosize > to->symsize()) + to->set_symsize(tosize); + if (tovalue > to->value()) + to->set_value(tovalue); + } + return; + } } // A new weak undefined reference, merging with an old weak // reference, could be a One Definition Rule (ODR) violation -- // especially if the types or sizes of the references differ. We'll // store such pairs and look them up later to make sure they - // actually refer to the same lines of code. (Note: not all ODR - // violations can be found this way, and not everything this finds - // is an ODR violation. But it's helpful to warn about.) - bool to_is_ordinary; + // actually refer to the same lines of code. We also check + // combinations of weak and strong, which might occur if one case is + // inline and the other is not. (Note: not all ODR violations can + // be found this way, and not everything this finds is an ODR + // violation. But it's helpful to warn about.) if (parameters->options().detect_odr_violations() - && sym.get_st_bind() == elfcpp::STB_WEAK - && to->binding() == elfcpp::STB_WEAK + && (sym.get_st_bind() == elfcpp::STB_WEAK + || to->binding() == elfcpp::STB_WEAK) && orig_st_shndx != elfcpp::SHN_UNDEF - && to->shndx(&to_is_ordinary) != elfcpp::SHN_UNDEF && to_is_ordinary + && to_shndx != elfcpp::SHN_UNDEF && sym.get_st_size() != 0 // Ignore weird 0-sized symbols. && to->symsize() != 0 && (sym.get_st_type() != to->type() @@ -259,12 +371,88 @@ Symbol_table::resolve(Sized_symbol* to, && to->name()[0] == '_' && to->name()[1] == 'Z') { Symbol_location fromloc - = { object, orig_st_shndx, sym.get_st_value() }; - Symbol_location toloc = { to->object(), to->shndx(&to_is_ordinary), - to->value() }; + = { object, orig_st_shndx, static_cast(sym.get_st_value()) }; + Symbol_location toloc = { to->object(), to_shndx, + static_cast(to->value()) }; this->candidate_odr_violations_[to->name()].insert(fromloc); this->candidate_odr_violations_[to->name()].insert(toloc); } + + // Plugins don't provide a symbol type, so adopt the existing type + // if the FROM symbol is from a plugin. + elfcpp::STT fromtype = (object->pluginobj() != NULL + ? to->type() + : sym.get_st_type()); + unsigned int frombits = symbol_to_bits(sym.get_st_bind(), + object->is_dynamic(), + st_shndx, is_ordinary); + + bool adjust_common_sizes; + bool adjust_dyndef; + typename Sized_symbol::Size_type tosize = to->symsize(); + if (Symbol_table::should_override(to, frombits, fromtype, OBJECT, + object, &adjust_common_sizes, + &adjust_dyndef, is_default_version)) + { + elfcpp::STB orig_tobinding = to->binding(); + typename Sized_symbol::Value_type tovalue = to->value(); + this->override(to, sym, st_shndx, is_ordinary, object, version); + if (adjust_common_sizes) + { + if (tosize > to->symsize()) + to->set_symsize(tosize); + if (tovalue > to->value()) + to->set_value(tovalue); + } + if (adjust_dyndef) + { + // We are overriding an UNDEF or WEAK UNDEF with a DYN DEF. + // Remember which kind of UNDEF it was for future reference. + to->set_undef_binding(orig_tobinding); + } + } + else + { + if (adjust_common_sizes) + { + if (sym.get_st_size() > tosize) + to->set_symsize(sym.get_st_size()); + if (sym.get_st_value() > to->value()) + to->set_value(sym.get_st_value()); + } + if (adjust_dyndef) + { + // We are keeping a DYN DEF after seeing an UNDEF or WEAK UNDEF. + // Remember which kind of UNDEF it was. + to->set_undef_binding(sym.get_st_bind()); + } + // The ELF ABI says that even for a reference to a symbol we + // merge the visibility. + to->override_visibility(sym.get_st_visibility()); + } + + // If we have a non-WEAK reference from a regular object to a + // dynamic object, mark the dynamic object as needed. + if (to->is_from_dynobj() && to->in_reg() && !to->is_undef_binding_weak()) + to->object()->set_is_needed(); + + if (adjust_common_sizes && parameters->options().warn_common()) + { + if (tosize > sym.get_st_size()) + Symbol_table::report_resolve_problem(false, + _("common of '%s' overriding " + "smaller common"), + to, OBJECT, object); + else if (tosize < sym.get_st_size()) + Symbol_table::report_resolve_problem(false, + _("common of '%s' overidden by " + "larger common"), + to, OBJECT, object); + else + Symbol_table::report_resolve_problem(false, + _("multiple common of '%s'"), + to, OBJECT, object); + } } // Handle the core of symbol resolution. This is called with the @@ -276,17 +464,18 @@ Symbol_table::resolve(Sized_symbol* to, bool Symbol_table::should_override(const Symbol* to, unsigned int frombits, - Object* object, bool* adjust_common_sizes) + elfcpp::STT fromtype, Defined defined, + Object* object, bool* adjust_common_sizes, + bool* adjust_dyndef, bool is_default_version) { *adjust_common_sizes = false; + *adjust_dyndef = false; unsigned int tobits; if (to->source() == Symbol::IS_UNDEFINED) - tobits = symbol_to_bits(to->binding(), false, elfcpp::SHN_UNDEF, true, - to->type()); + tobits = symbol_to_bits(to->binding(), false, elfcpp::SHN_UNDEF, true); else if (to->source() != Symbol::FROM_OBJECT) - tobits = symbol_to_bits(to->binding(), false, elfcpp::SHN_ABS, false, - to->type()); + tobits = symbol_to_bits(to->binding(), false, elfcpp::SHN_ABS, false); else { bool is_ordinary; @@ -294,11 +483,15 @@ Symbol_table::should_override(const Symbol* to, unsigned int frombits, tobits = symbol_to_bits(to->binding(), to->object()->is_dynamic(), shndx, - is_ordinary, - to->type()); + is_ordinary); } - // FIXME: Warn if either but not both of TO and SYM are STT_TLS. + if ((to->type() == elfcpp::STT_TLS) ^ (fromtype == elfcpp::STT_TLS) + && !to->is_placeholder()) + Symbol_table::report_resolve_problem(true, + _("symbol '%s' used as both __thread " + "and non-__thread"), + to, defined, object); // We use a giant switch table for symbol resolution. This code is // unwieldy, but: 1) it is efficient; 2) we definitely handle all @@ -334,17 +527,13 @@ Symbol_table::should_override(const Symbol* to, unsigned int frombits, // --just-symbols, then don't warn. This is for compatibility // with the GNU linker. FIXME: This is a hack. if ((to->source() == Symbol::FROM_OBJECT && to->object()->just_symbols()) - || object->just_symbols()) + || (object != NULL && object->just_symbols())) return false; - // FIXME: Do a better job of reporting locations. - gold_error(_("%s: multiple definition of %s"), - object != NULL ? object->name().c_str() : _("command line"), - to->demangled_name().c_str()); - gold_error(_("%s: previous definition here"), - (to->source() == Symbol::FROM_OBJECT - ? to->object()->name().c_str() - : _("command line"))); + if (!parameters->options().muldefs()) + Symbol_table::report_resolve_problem(true, + _("multiple definition of '%s'"), + to, defined, object); return false; case WEAK_DEF * 16 + DEF: @@ -379,8 +568,12 @@ Symbol_table::should_override(const Symbol* to, unsigned int frombits, case DYN_COMMON * 16 + DEF: case DYN_WEAK_COMMON * 16 + DEF: // We've seen a common symbol and now we see a definition. The - // definition overrides. FIXME: We should optionally issue, version a - // warning. + // definition overrides. + if (parameters->options().warn_common()) + Symbol_table::report_resolve_problem(false, + _("definition of '%s' overriding " + "common"), + to, defined, object); return true; case DEF * 16 + WEAK_DEF: @@ -410,62 +603,112 @@ Symbol_table::should_override(const Symbol* to, unsigned int frombits, case DYN_COMMON * 16 + WEAK_DEF: case DYN_WEAK_COMMON * 16 + WEAK_DEF: // A weak definition does override a definition in a dynamic - // object. FIXME: We should optionally issue a warning. + // object. + if (parameters->options().warn_common()) + Symbol_table::report_resolve_problem(false, + _("definition of '%s' overriding " + "dynamic common definition"), + to, defined, object); return true; case DEF * 16 + DYN_DEF: case WEAK_DEF * 16 + DYN_DEF: + // Ignore a dynamic definition if we already have a definition. + return false; + case DYN_DEF * 16 + DYN_DEF: case DYN_WEAK_DEF * 16 + DYN_DEF: - // Ignore a dynamic definition if we already have a definition. + // Ignore a dynamic definition if we already have a definition, + // unless the existing definition is an unversioned definition + // in the same dynamic object, and the new definition is a + // default version. + if (to->object() == object + && to->version() == NULL + && is_default_version) + return true; + // Or, if the existing definition is in an unused --as-needed library, + // and the reference is weak, let the new definition override. + if (to->in_reg() + && to->is_undef_binding_weak() + && to->object()->as_needed() + && !to->object()->is_needed()) + return true; return false; case UNDEF * 16 + DYN_DEF: - case WEAK_UNDEF * 16 + DYN_DEF: case DYN_UNDEF * 16 + DYN_DEF: case DYN_WEAK_UNDEF * 16 + DYN_DEF: // Use a dynamic definition if we have a reference. return true; + case WEAK_UNDEF * 16 + DYN_DEF: + // When overriding a weak undef by a dynamic definition, + // we need to remember that the original undef was weak. + *adjust_dyndef = true; + return true; + case COMMON * 16 + DYN_DEF: case WEAK_COMMON * 16 + DYN_DEF: - case DYN_COMMON * 16 + DYN_DEF: - case DYN_WEAK_COMMON * 16 + DYN_DEF: // Ignore a dynamic definition if we already have a common // definition. return false; case DEF * 16 + DYN_WEAK_DEF: case WEAK_DEF * 16 + DYN_WEAK_DEF: - case DYN_DEF * 16 + DYN_WEAK_DEF: - case DYN_WEAK_DEF * 16 + DYN_WEAK_DEF: // Ignore a weak dynamic definition if we already have a // definition. return false; case UNDEF * 16 + DYN_WEAK_DEF: - case WEAK_UNDEF * 16 + DYN_WEAK_DEF: + // When overriding an undef by a dynamic weak definition, + // we need to remember that the original undef was not weak. + *adjust_dyndef = true; + return true; + case DYN_UNDEF * 16 + DYN_WEAK_DEF: case DYN_WEAK_UNDEF * 16 + DYN_WEAK_DEF: // Use a weak dynamic definition if we have a reference. return true; + case WEAK_UNDEF * 16 + DYN_WEAK_DEF: + // When overriding a weak undef by a dynamic definition, + // we need to remember that the original undef was weak. + *adjust_dyndef = true; + return true; + case COMMON * 16 + DYN_WEAK_DEF: case WEAK_COMMON * 16 + DYN_WEAK_DEF: - case DYN_COMMON * 16 + DYN_WEAK_DEF: - case DYN_WEAK_COMMON * 16 + DYN_WEAK_DEF: // Ignore a weak dynamic definition if we already have a common // definition. return false; + case DYN_COMMON * 16 + DYN_DEF: + case DYN_WEAK_COMMON * 16 + DYN_DEF: + case DYN_DEF * 16 + DYN_WEAK_DEF: + case DYN_WEAK_DEF * 16 + DYN_WEAK_DEF: + case DYN_COMMON * 16 + DYN_WEAK_DEF: + case DYN_WEAK_COMMON * 16 + DYN_WEAK_DEF: + // If the existing definition is in an unused --as-needed library, + // and the reference is weak, let a new dynamic definition override. + if (to->in_reg() + && to->is_undef_binding_weak() + && to->object()->as_needed() + && !to->object()->is_needed()) + return true; + return false; + case DEF * 16 + UNDEF: case WEAK_DEF * 16 + UNDEF: - case DYN_DEF * 16 + UNDEF: - case DYN_WEAK_DEF * 16 + UNDEF: case UNDEF * 16 + UNDEF: // A new undefined reference tells us nothing. return false; + case DYN_DEF * 16 + UNDEF: + case DYN_WEAK_DEF * 16 + UNDEF: + // For a dynamic def, we need to remember which kind of undef we see. + *adjust_dyndef = true; + return false; + case WEAK_UNDEF * 16 + UNDEF: case DYN_UNDEF * 16 + UNDEF: case DYN_WEAK_UNDEF * 16 + UNDEF: @@ -481,17 +724,28 @@ Symbol_table::should_override(const Symbol* to, unsigned int frombits, case DEF * 16 + WEAK_UNDEF: case WEAK_DEF * 16 + WEAK_UNDEF: - case DYN_DEF * 16 + WEAK_UNDEF: - case DYN_WEAK_DEF * 16 + WEAK_UNDEF: case UNDEF * 16 + WEAK_UNDEF: case WEAK_UNDEF * 16 + WEAK_UNDEF: case DYN_UNDEF * 16 + WEAK_UNDEF: - case DYN_WEAK_UNDEF * 16 + WEAK_UNDEF: case COMMON * 16 + WEAK_UNDEF: case WEAK_COMMON * 16 + WEAK_UNDEF: case DYN_COMMON * 16 + WEAK_UNDEF: case DYN_WEAK_COMMON * 16 + WEAK_UNDEF: - // A new weak undefined reference tells us nothing. + // A new weak undefined reference tells us nothing unless the + // exisiting symbol is a dynamic weak reference. + return false; + + case DYN_WEAK_UNDEF * 16 + WEAK_UNDEF: + // A new weak reference overrides an existing dynamic weak reference. + // This is necessary because a dynamic weak reference remembers + // the old binding, which may not be weak. If we keeps the existing + // dynamic weak reference, the weakness may be dropped in the output. + return true; + + case DYN_DEF * 16 + WEAK_UNDEF: + case DYN_WEAK_DEF * 16 + WEAK_UNDEF: + // For a dynamic def, we need to remember which kind of undef we see. + *adjust_dyndef = true; return false; case DEF * 16 + DYN_UNDEF: @@ -526,6 +780,11 @@ Symbol_table::should_override(const Symbol* to, unsigned int frombits, case DEF * 16 + COMMON: // A common symbol does not override a definition. + if (parameters->options().warn_common()) + Symbol_table::report_resolve_problem(false, + _("common '%s' overridden by " + "previous definition"), + to, defined, object); return false; case WEAK_DEF * 16 + COMMON: @@ -631,18 +890,135 @@ Symbol_table::should_override(const Symbol* to, unsigned int frombits, } } +// Issue an error or warning due to symbol resolution. IS_ERROR +// indicates an error rather than a warning. MSG is the error +// message; it is expected to have a %s for the symbol name. TO is +// the existing symbol. DEFINED/OBJECT is where the new symbol was +// found. + +// FIXME: We should have better location information here. When the +// symbol is defined, we should be able to pull the location from the +// debug info if there is any. + +void +Symbol_table::report_resolve_problem(bool is_error, const char* msg, + const Symbol* to, Defined defined, + Object* object) +{ + std::string demangled(to->demangled_name()); + size_t len = strlen(msg) + demangled.length() + 10; + char* buf = new char[len]; + snprintf(buf, len, msg, demangled.c_str()); + + const char* objname; + switch (defined) + { + case OBJECT: + objname = object->name().c_str(); + break; + case COPY: + objname = _("COPY reloc"); + break; + case DEFSYM: + case UNDEFINED: + objname = _("command line"); + break; + case SCRIPT: + objname = _("linker script"); + break; + case PREDEFINED: + case INCREMENTAL_BASE: + objname = _("linker defined"); + break; + default: + gold_unreachable(); + } + + if (is_error) + gold_error("%s: %s", objname, buf); + else + gold_warning("%s: %s", objname, buf); + + delete[] buf; + + if (to->source() == Symbol::FROM_OBJECT) + objname = to->object()->name().c_str(); + else + objname = _("command line"); + gold_info("%s: %s: previous definition here", program_name, objname); +} + +// Completely override existing symbol. Everything bar name_, +// version_, and is_forced_local_ flag are copied. version_ is +// cleared if from->version_ is clear. Returns true if this symbol +// should be forced local. +bool +Symbol::clone(const Symbol* from) +{ + // Don't allow cloning after dynamic linking info is attached to symbols. + // We aren't prepared to merge such. + gold_assert(!this->has_symtab_index() && !from->has_symtab_index()); + gold_assert(!this->has_dynsym_index() && !from->has_dynsym_index()); + gold_assert(this->got_offset_list() == NULL + && from->got_offset_list() == NULL); + gold_assert(!this->has_plt_offset() && !from->has_plt_offset()); + + if (!from->version_) + this->version_ = from->version_; + this->u1_ = from->u1_; + this->u2_ = from->u2_; + this->type_ = from->type_; + this->binding_ = from->binding_; + this->visibility_ = from->visibility_; + this->nonvis_ = from->nonvis_; + this->source_ = from->source_; + this->is_def_ = from->is_def_; + this->is_forwarder_ = from->is_forwarder_; + this->has_alias_ = from->has_alias_; + this->needs_dynsym_entry_ = from->needs_dynsym_entry_; + this->in_reg_ = from->in_reg_; + this->in_dyn_ = from->in_dyn_; + this->needs_dynsym_value_ = from->needs_dynsym_value_; + this->has_warning_ = from->has_warning_; + this->is_copied_from_dynobj_ = from->is_copied_from_dynobj_; + this->is_ordinary_shndx_ = from->is_ordinary_shndx_; + this->in_real_elf_ = from->in_real_elf_; + this->is_defined_in_discarded_section_ + = from->is_defined_in_discarded_section_; + this->undef_binding_set_ = from->undef_binding_set_; + this->undef_binding_weak_ = from->undef_binding_weak_; + this->is_predefined_ = from->is_predefined_; + this->is_protected_ = from->is_protected_; + this->non_zero_localentry_ = from->non_zero_localentry_; + + return !this->is_forced_local_ && from->is_forced_local_; +} + +template +bool +Sized_symbol::clone(const Sized_symbol* from) +{ + this->value_ = from->value_; + this->symsize_ = from->symsize_; + return Symbol::clone(from); +} + // A special case of should_override which is only called for a strong // defined symbol from a regular object file. This is used when // defining special symbols. bool -Symbol_table::should_override_with_special(const Symbol* to) +Symbol_table::should_override_with_special(const Symbol* to, + elfcpp::STT fromtype, + Defined defined) { bool adjust_common_sizes; + bool adjust_dyn_def; unsigned int frombits = global_flag | regular_flag | def_flag; - bool ret = Symbol_table::should_override(to, frombits, NULL, - &adjust_common_sizes); - gold_assert(!adjust_common_sizes); + bool ret = Symbol_table::should_override(to, frombits, fromtype, defined, + NULL, &adjust_common_sizes, + &adjust_dyn_def, false); + gold_assert(!adjust_common_sizes && !adjust_dyn_def); return ret; } @@ -651,19 +1027,21 @@ Symbol_table::should_override_with_special(const Symbol* to) void Symbol::override_base_with_special(const Symbol* from) { - gold_assert(this->name_ == from->name_ || this->has_alias()); + bool same_name = this->name_ == from->name_; + gold_assert(same_name || this->has_alias()); + + // If we are overriding an undef, remember the original binding. + if (this->is_undefined()) + this->set_undef_binding(this->binding_); this->source_ = from->source_; switch (from->source_) { case FROM_OBJECT: - this->u_.from_object = from->u_.from_object; - break; case IN_OUTPUT_DATA: - this->u_.in_output_data = from->u_.in_output_data; - break; case IN_OUTPUT_SEGMENT: - this->u_.in_output_segment = from->u_.in_output_segment; + this->u1_ = from->u1_; + this->u2_ = from->u2_; break; case IS_CONSTANT: case IS_UNDEFINED: @@ -673,15 +1051,19 @@ Symbol::override_base_with_special(const Symbol* from) break; } - if (from->version_ != NULL && this->version_ != from->version_) + if (same_name) { - gold_assert(this->version_ == NULL); + // When overriding a versioned symbol with a special symbol, we + // may be changing the version. This will happen if we see a + // special symbol such as "_end" defined in a shared object with + // one version (from a version script), but we want to define it + // here with a different version (from a different version + // script). this->version_ = from->version_; } - this->type_ = from->type_; this->binding_ = from->binding_; - this->visibility_ = from->visibility_; + this->override_visibility(from->visibility_); this->nonvis_ = from->nonvis_; // Special symbols are always considered to be regular symbols. @@ -692,11 +1074,12 @@ Symbol::override_base_with_special(const Symbol* from) if (from->needs_dynsym_value_) this->needs_dynsym_value_ = true; + this->is_predefined_ = from->is_predefined_; + // We shouldn't see these flags. If we do, we need to handle them // somehow. - gold_assert(!from->is_target_special_ || this->is_target_special_); gold_assert(!from->is_forwarder_); - gold_assert(!from->has_plt_offset_); + gold_assert(!from->has_plt_offset()); gold_assert(!from->has_warning_); gold_assert(!from->is_copied_from_dynobj_); gold_assert(!from->is_forced_local_); @@ -736,7 +1119,13 @@ Symbol_table::override_with_special(Sized_symbol* tosym, } while (ssym != tosym); } - if (tosym->binding() == elfcpp::STB_LOCAL) + if (tosym->binding() == elfcpp::STB_LOCAL + || ((tosym->visibility() == elfcpp::STV_HIDDEN + || tosym->visibility() == elfcpp::STV_INTERNAL) + && (tosym->binding() == elfcpp::STB_GLOBAL + || tosym->binding() == elfcpp::STB_GNU_UNIQUE + || tosym->binding() == elfcpp::STB_WEAK) + && !parameters->options().relocatable())) this->force_local(tosym); } @@ -744,7 +1133,10 @@ Symbol_table::override_with_special(Sized_symbol* tosym, // script to restrict this to only the ones needed for implemented // targets. -#ifdef HAVE_TARGET_32_LITTLE +// We have to instantiate both big and little endian versions because +// these are used by other templates that depends on size only. + +#if defined(HAVE_TARGET_32_LITTLE) || defined(HAVE_TARGET_32_BIG) template void Symbol_table::resolve<32, false>( @@ -754,10 +1146,9 @@ Symbol_table::resolve<32, false>( bool is_ordinary, unsigned int orig_st_shndx, Object* object, - const char* version); -#endif + const char* version, + bool is_default_version); -#ifdef HAVE_TARGET_32_BIG template void Symbol_table::resolve<32, true>( @@ -767,10 +1158,11 @@ Symbol_table::resolve<32, true>( bool is_ordinary, unsigned int orig_st_shndx, Object* object, - const char* version); + const char* version, + bool is_default_version); #endif -#ifdef HAVE_TARGET_64_LITTLE +#if defined(HAVE_TARGET_64_LITTLE) || defined(HAVE_TARGET_64_BIG) template void Symbol_table::resolve<64, false>( @@ -780,10 +1172,9 @@ Symbol_table::resolve<64, false>( bool is_ordinary, unsigned int orig_st_shndx, Object* object, - const char* version); -#endif + const char* version, + bool is_default_version); -#ifdef HAVE_TARGET_64_BIG template void Symbol_table::resolve<64, true>( @@ -793,7 +1184,8 @@ Symbol_table::resolve<64, true>( bool is_ordinary, unsigned int orig_st_shndx, Object* object, - const char* version); + const char* version, + bool is_default_version); #endif #if defined(HAVE_TARGET_32_LITTLE) || defined(HAVE_TARGET_32_BIG) @@ -810,4 +1202,11 @@ Symbol_table::override_with_special<64>(Sized_symbol<64>*, const Sized_symbol<64>*); #endif +template +bool +Sized_symbol<32>::clone(const Sized_symbol<32>*); + +template +bool +Sized_symbol<64>::clone(const Sized_symbol<64>*); } // End namespace gold.