// resolve.cc -- symbol resolution for gold
-// Copyright 2006, 2007, 2008, 2009, 2010 Free Software Foundation, Inc.
+// Copyright (C) 2006-2015 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();
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<int>(binding));
bits = global_flag;
}
unsigned int orig_st_shndx,
Object* object, const char* 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
+ // 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
+ && to_is_ordinary
+ && to->value() == sym.get_st_value())
+ return;
+
if (parameters->target().has_resolve())
{
Sized_target<size, big_endian>* sized_target;
// 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 && st_shndx == elfcpp::SHN_COMMON)
+ {
+ 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;
}
}
// 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.)
- bool to_is_ordinary;
if (parameters->options().detect_odr_violations()
&& (sym.get_st_bind() == elfcpp::STB_WEAK
|| to->binding() == elfcpp::STB_WEAK)
&& 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());
+ fromtype);
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,
+ if (Symbol_table::should_override(to, frombits, fromtype, OBJECT,
+ object, &adjust_common_sizes,
&adjust_dyndef))
{
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,
+ elfcpp::STT fromtype, Defined defined,
+ Object* object, bool* adjust_common_sizes,
bool* adjust_dyndef)
{
*adjust_common_sizes = false;
to->type());
}
- // 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
return false;
case 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.
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.
objname = _("linker script");
break;
case PREDEFINED:
+ case INCREMENTAL_BASE:
objname = _("linker defined");
break;
default:
// 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,
+ bool ret = Symbol_table::should_override(to, frombits, fromtype, defined,
+ NULL, &adjust_common_sizes,
&adjust_dyn_def);
gold_assert(!adjust_common_sizes && !adjust_dyn_def);
return ret;
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_)
break;
}
- this->override_version(from->version_);
+ if (same_name)
+ {
+ // 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_);
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_forwarder_);
projects / deliverable / binutils-gdb.git / blobdiff