gold/testsuite/weak_undef_test.cc

   1 // weak_undef_test.cc -- test handling of weak undefined symbols for gold
   2
   3 // Copyright 2008 Free Software Foundation, Inc.
   4 // Written by Cary Coutant <ccoutant@google.com>.
   5
   6 // This file is part of gold.
   7
   8 // This program is free software; you can redistribute it and/or modify
   9 // it under the terms of the GNU General Public License as published by
  10 // the Free Software Foundation; either version 3 of the License, or
  11 // (at your option) any later version.
  12
  13 // This program is distributed in the hope that it will be useful,
  14 // but WITHOUT ANY WARRANTY; without even the implied warranty of
  15 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16 // GNU General Public License for more details.
  17
  18 // You should have received a copy of the GNU General Public License
  19 // along with this program; if not, write to the Free Software
  20 // Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston,
  21 // MA 02110-1301, USA.
  22
  23 // We test that we correctly deal with weak undefined symbols.
  24 // We need to make sure that a weak undefined symbol in the main
  25 // program is resolved to zero by the linker and that no dynamic
  26 // relocation is generated.  We also make sure that a weak undefined
  27 // symbol in a shared library can resolve to a symbol in the main
  28 // program.
  29
  30 // This file will be linked with a shared library that does not
  31 // define the symbol, so that the symbol remains undefined.
  32 // Through the use of LD_LIBRARY_PATH, the program will load
  33 // an alternate shared library that does define the symbol,
  34 // so that we can detect whether the symbol was left for runtime
  35 // resolution.
  36
  37
  38 #include <cstdio>
  39 #include "weak_undef.h"
  40
  41 extern int no_such_symbol_ __attribute__ ((weak));
  42
  43 int *p1 = &no_such_symbol_;
  44
  45 int v2 = 42;
  46
  47 int
  48 main()
  49 {
  50   int status = 0;
  51   int v;
  52
  53   if ((v = t1()) != 2)
  54     {
  55       fprintf(stderr, "FAILED weak undef test 1: %s\n",
  56               "bound to wrong library");
  57       status = 1;
  58     }
  59
  60   if ((v = t2()) != 42)
  61     {
  62       fprintf(stderr, "FAILED weak undef test 2: expected %d, got %d\n",
  63               42, v);
  64       status = 1;
  65     }
  66
  67   if ((v = t3()) != 42)
  68     {
  69       fprintf(stderr, "FAILED weak undef test 3: expected %d, got %d\n",
  70               42, v);
  71       status = 1;
  72     }
  73
  74   if (&no_such_symbol_ != NULL)
  75     {
  76       fprintf(stderr, "FAILED weak undef test 4: %s\n",
  77               "&no_such_symbol_ is not NULL");
  78       status = 1;
  79     }
  80
  81   if (p1 != NULL)
  82     {
  83       fprintf(stderr, "FAILED weak undef test 5: %s\n",
  84               "p1 is not NULL");
  85       status = 1;
  86     }
  87
  88   return status;
  89 }