// resolve.cc -- symbol resolution for gold
-// Copyright 2006, 2007, 2008, 2009, 2010, 2011 Free Software Foundation, Inc.
+// Copyright (C) 2006-2020 Free Software Foundation, Inc.
// Written by Ian Lance Taylor <iant@google.com>.
// This file is part of gold.
Object* object, const char* version)
{
gold_assert(this->source_ == FROM_OBJECT);
- this->u_.from_object.object = object;
+ this->u1_.object = object;
this->override_version(version);
- this->u_.from_object.shndx = st_shndx;
+ 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->override_visibility(sym.get_st_visibility());
this->nonvis_ = sym.get_st_nonvis();
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;
// 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
break;
default:
- if (type == elfcpp::STT_COMMON)
- bits |= common_flag;
- else if (!is_ordinary && Symbol::is_common_shndx(shndx))
+ if (!is_ordinary && Symbol::is_common_shndx(shndx))
bits |= common_flag;
else
bits |= def_flag;
const elfcpp::Sym<size, big_endian>& 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)
{
+ 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.
- bool to_is_ordinary;
if (to->source() == Symbol::FROM_OBJECT
&& to->object() == object
- && is_ordinary
&& to->is_defined()
- && to->shndx(&to_is_ordinary) == st_shndx
+ && 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;
{
Sized_target<size, big_endian>* sized_target;
sized_target = parameters->sized_target<size, big_endian>();
- sized_target->resolve(to, sym, object, version);
- return;
+ 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();
}
&& (to->visibility() == elfcpp::STV_HIDDEN
|| to->visibility() == elfcpp::STV_INTERNAL))
{
- // A dynamic object cannot reference a hidden or internal symbol
- // defined in another object.
- gold_warning(_("%s symbol '%s' in %s is referenced by DSO %s"),
- (to->visibility() == elfcpp::STV_HIDDEN
- ? "hidden"
- : "internal"),
- to->demangled_name().c_str(),
- to->object()->name().c_str(),
- object->name().c_str());
+ // 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
// 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)
{
Pluginobj* obj = to->object()->pluginobj();
if (obj != NULL
&& parameters->options().plugins()->in_replacement_phase())
{
- this->override(to, sym, st_shndx, is_ordinary, object, version);
- return;
+ bool adjust_common = false;
+ typename Sized_symbol<size>::Size_type tosize = 0;
+ typename Sized_symbol<size>::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;
}
}
&& (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()
{
Symbol_location fromloc
= { object, orig_st_shndx, static_cast<off_t>(sym.get_st_value()) };
- Symbol_location toloc = { to->object(), to->shndx(&to_is_ordinary),
+ Symbol_location toloc = { to->object(), to_shndx,
static_cast<off_t>(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,
- sym.get_st_type());
+ st_shndx, is_ordinary);
bool adjust_common_sizes;
bool adjust_dyndef;
typename Sized_symbol<size>::Size_type tosize = to->symsize();
- if (Symbol_table::should_override(to, frombits, sym.get_st_type(), OBJECT,
+ if (Symbol_table::should_override(to, frombits, fromtype, OBJECT,
object, &adjust_common_sizes,
- &adjust_dyndef))
+ &adjust_dyndef, is_default_version))
{
- elfcpp::STB tobinding = to->binding();
+ elfcpp::STB orig_tobinding = to->binding();
typename Sized_symbol<size>::Value_type tovalue = to->value();
this->override(to, sym, st_shndx, is_ordinary, object, version);
if (adjust_common_sizes)
{
// 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(tobinding);
+ to->set_undef_binding(orig_tobinding);
}
}
else
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::should_override(const Symbol* to, unsigned int frombits,
elfcpp::STT fromtype, Defined defined,
Object* object, bool* adjust_common_sizes,
- bool* adjust_dyndef)
+ 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;
tobits = symbol_to_bits(to->binding(),
to->object()->is_dynamic(),
shndx,
- is_ordinary,
- to->type());
+ is_ordinary);
}
- if (to->type() == elfcpp::STT_TLS
- ? fromtype != elfcpp::STT_TLS
- : fromtype == elfcpp::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"),
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 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 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 UNDEF * 16 + UNDEF:
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 <int size>
+bool
+Sized_symbol<size>::clone(const Sized_symbol<size>* 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.
unsigned int frombits = global_flag | regular_flag | def_flag;
bool ret = Symbol_table::should_override(to, frombits, fromtype, defined,
NULL, &adjust_common_sizes,
- &adjust_dyn_def);
+ &adjust_dyn_def, false);
gold_assert(!adjust_common_sizes && !adjust_dyn_def);
return ret;
}
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:
bool is_ordinary,
unsigned int orig_st_shndx,
Object* object,
- const char* version);
+ const char* version,
+ bool is_default_version);
template
void
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_64_LITTLE) || defined(HAVE_TARGET_64_BIG)
bool is_ordinary,
unsigned int orig_st_shndx,
Object* object,
- const char* version);
+ const char* version,
+ bool is_default_version);
template
void
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)
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.