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// weak_undef_file1.cc -- test handling of weak undefined symbols for gold
// Copyright 2008, 2010 Free Software Foundation, Inc.
// Written by Cary Coutant <ccoutant@google.com>.
// This file is part of gold.
// This program is free software; you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation; either version 3 of the License, or
// (at your option) any later version.
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU General Public License for more details.
// You should have received a copy of the GNU General Public License
// along with this program; if not, write to the Free Software
// Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston,
// MA 02110-1301, USA.
// We test that we correctly deal with weak undefined symbols.
// We need to make sure that the symbol is resolved to zero
// by the linker and that no dynamic relocation is generated.
// This source is used to build a shared library that defines
// an arbitrary symbol other than the weak undefined symbol
// referenced by the main program. The main program will be
// linked with this library so that the symbol remains undefined.
// Through the use of the embedded RPATH, the program will load
// an alternate shared library that does define the symbol,
// so that we can detect whether the symbol was left for runtime
// resolution.
#include <cstdio>
#include "weak_undef.h"
int is_such_symbol_ = 1;
// We also define a symbol that is not defined by the alternate
// library. The main program contains a weak reference to this
// symbol, and tests that the reference remains weak even after
// the definition was found at link time.
int link_time_only = 1;
extern int v2 __attribute__ ((weak));
int *v3 = &v2;
int
t1()
{
return is_such_symbol_;
}
// Test that a weak reference from a shared library to a symbol
// defined in the main program does get resolved.
int
t2()
{
return (&v2 == NULL) ? -1 : v2;
}
// Test that a weak reference from a shared library to a symbol
// defined in the main program does get resolved.
int
t3()
{
return (v3 == NULL) ? -1 : *v3;
}
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