// resolve.cc -- symbol resolution for gold
-// Copyright 2006, 2007, 2008, 2009, 2010, 2011 Free Software Foundation, Inc.
+// Copyright (C) 2006-2016 Free Software Foundation, Inc.
// Written by Ian Lance Taylor <iant@google.com>.
// This file is part of gold.
this->override_version(version);
this->u_.from_object.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;
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)
{
// 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
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
// 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)
+ if (object->pluginobj() == NULL && !object->is_dynamic())
to->set_in_real_elf();
// 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;
}
}
&& to->name()[0] == '_' && to->name()[1] == 'Z')
{
Symbol_location fromloc
- = { object, orig_st_shndx, sym.get_st_value() };
+ = { object, orig_st_shndx, static_cast<off_t>(sym.get_st_value()) };
Symbol_location toloc = { to->object(), to->shndx(&to_is_ordinary),
- to->value() };
+ 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, OBJECT, object,
- &adjust_common_sizes,
- &adjust_dyndef))
+ if (Symbol_table::should_override(to, frombits, fromtype, OBJECT,
+ object, &adjust_common_sizes,
+ &adjust_dyndef, is_default_version))
{
elfcpp::STB 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 && tosize > to->symsize())
- to->set_symsize(tosize);
+ 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.
}
else
{
- if (adjust_common_sizes && sym.get_st_size() > tosize)
- to->set_symsize(sym.get_st_size());
+ 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.
bool
Symbol_table::should_override(const Symbol* to, unsigned int frombits,
- Defined defined, Object* object,
- bool* adjust_common_sizes,
- bool* adjust_dyndef)
+ 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;
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
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;
return false;
case UNDEF * 16 + DYN_DEF:
// defining special symbols.
bool
-Symbol_table::should_override_with_special(const Symbol* to, Defined defined)
+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, defined, NULL,
- &adjust_common_sizes,
- &adjust_dyn_def);
+ 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;
}
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_)
{
}
if (same_name)
- this->override_version(from->version_);
+ {
+ // 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->override_visibility(from->visibility_);
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)