gold/testsuite/justsyms_1.cc

   1 // justsyms_1.cc -- test --just-symbols for gold
   2
   3 // Copyright (C) 2008-2017 Free Software Foundation, Inc.
   4 // Written by Ian Lance Taylor <iant@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 // The Linux kernel builds an object file using a linker script, and
  24 // then links against that object file using the -R option.  This is a
  25 // test for that usage.
  26
  27 #include <cassert>
  28 #include <csignal>
  29 #include <cstddef>
  30 #include <cstdlib>
  31 #include <stdint.h>
  32
  33 extern char justsyms_string[];
  34
  35 // We expect to get a SIGSEGV.
  36 static void
  37 handle_sigsegv(int)
  38 {
  39   exit(0);
  40 }
  41
  42 int
  43 main(int, char**)
  44 {
  45   // The linker script should arrange for this symbol to be exactly at
  46   // address 0x10000.
  47   assert(reinterpret_cast<uintptr_t>(justsyms_string) == 0x100);
  48
  49   // However, since the file was linked with --just-symbols, we should
  50   // not be able to actually access the symbol.
  51   signal(SIGSEGV, handle_sigsegv);
  52   char c = justsyms_string[0];
  53   exit(c == '\0' ? 1 : c);
  54 }