gold/testsuite/ehdr_start_test.cc

   1 // ehdr_start_test.cc -- test for __ehdr_start linker-defined symbol.
   2
   3 // Copyright (C) 2014-2022 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 // The goal of this program is to produce as many different types of
  24 // relocations as we can in a stand-alone program that does not use
  25 // TLS.  This program is compiled without optimization.
  26
  27 #include "config.h"
  28
  29 #include <cassert>
  30 #include <cstdio>
  31
  32 #include "elfcpp.h"
  33
  34 #ifdef EHDR_START_WEAK
  35 #define WEAK_ATTR __attribute__ ((weak))
  36 #else
  37 #define WEAK_ATTR
  38 #endif
  39
  40 extern char __ehdr_start[] WEAK_ATTR;
  41
  42 int
  43 main() {
  44   printf("&__ehdr_start = %p\n", &__ehdr_start);
  45
  46 #ifdef EHDR_START_UNDEF
  47   assert(&__ehdr_start == 0);
  48 #else
  49   assert(&__ehdr_start != NULL);
  50
  51   printf("ELF header: \\x%02x%c%c%c\n", __ehdr_start[0], __ehdr_start[1],
  52          __ehdr_start[2], __ehdr_start[3]);
  53 #ifdef EHDR_START_USER_DEF
  54   assert(__ehdr_start[0] == 'a'
  55          && __ehdr_start[1] == 'b'
  56          && __ehdr_start[2] == 'c'
  57          && __ehdr_start[3] == 'd');
  58 #else
  59   assert(__ehdr_start[elfcpp::EI_MAG0] == elfcpp::ELFMAG0
  60          && __ehdr_start[elfcpp::EI_MAG1] == elfcpp::ELFMAG1
  61          && __ehdr_start[elfcpp::EI_MAG2] == elfcpp::ELFMAG2
  62          && __ehdr_start[elfcpp::EI_MAG3] == elfcpp::ELFMAG3);
  63 #endif
  64 #endif
  65
  66   return 0;
  67 }