// weak_undef_test.cc -- test handling of weak undefined symbols for gold // Copyright (C) 2008-2014 Free Software Foundation, Inc. // Written by Cary Coutant . // 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 a weak undefined symbol in the main // program is resolved to zero by the linker and that no dynamic // relocation is generated. We also make sure that a weak undefined // symbol in a shared library can resolve to a symbol in the main // program. // This file will be linked with a shared library that does not // define the symbol, so that the symbol remains undefined. // Through the use of LD_LIBRARY_PATH, 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. // Similarly, this file will be linked with a shared library that // does define a different symbol, and loaded with an alternate // shared library that does not define that symbol. We check that // the weak reference remains weak, and that it is resolved to // zero at runtime. #include #include "weak_undef.h" extern int no_such_symbol_ __attribute__ ((weak)); extern int link_time_only __attribute__ ((weak)); int *p1 = &no_such_symbol_; int *p2 = &link_time_only; int v2 = 42; int main() { int status = 0; int v; if ((v = t1()) != 2) { fprintf(stderr, "FAILED weak undef test 1: %s\n", "bound to wrong library"); status = 1; } if ((v = t2()) != 42) { fprintf(stderr, "FAILED weak undef test 2: expected %d, got %d\n", 42, v); status = 1; } if ((v = t3()) != 42) { fprintf(stderr, "FAILED weak undef test 3: expected %d, got %d\n", 42, v); status = 1; } if (&no_such_symbol_ != NULL) { fprintf(stderr, "FAILED weak undef test 4: %s\n", "&no_such_symbol_ is not NULL"); status = 1; } if (p1 != NULL) { fprintf(stderr, "FAILED weak undef test 5: %s\n", "p1 is not NULL"); status = 1; } if (p2 != NULL) { fprintf(stderr, "FAILED weak undef test 6: %s\n", "p2 is not NULL"); status = 1; } return status; }