gold/defstd.cc

   1 // defstd.cc -- define standard symbols for gold.
   2
   3 // Copyright 2006, 2007 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 #include "gold.h"
  24
  25 #include "symtab.h"
  26 #include "layout.h"
  27 #include "defstd.h"
  28
  29 // This is a simple file which defines the standard symbols like
  30 // "_end".
  31
  32 namespace
  33 {
  34
  35 using namespace gold;
  36
  37 const Define_symbol_in_section in_section[] =
  38 {
  39   {
  40     "__preinit_array_start",    // name
  41     ".preinit_array",           // output_section
  42     0,                          // value
  43     0,                          // size
  44     elfcpp::STT_NOTYPE,         // type
  45     elfcpp::STB_GLOBAL,         // binding
  46     elfcpp::STV_HIDDEN,         // visibility
  47     0,                          // nonvis
  48     false,                      // offset_is_from_end
  49     true                        // only_if_ref
  50   },
  51   {
  52     "__preinit_array_end",      // name
  53     ".preinit_array",           // output_section
  54     0,                          // value
  55     0,                          // size
  56     elfcpp::STT_NOTYPE,         // type
  57     elfcpp::STB_GLOBAL,         // binding
  58     elfcpp::STV_HIDDEN,         // visibility
  59     0,                          // nonvis
  60     true,                       // offset_is_from_end
  61     true                        // only_if_ref
  62   },
  63   {
  64     "__init_array_start",       // name
  65     ".init_array",              // output_section
  66     0,                          // value
  67     0,                          // size
  68     elfcpp::STT_NOTYPE,         // type
  69     elfcpp::STB_GLOBAL,         // binding
  70     elfcpp::STV_HIDDEN,         // visibility
  71     0,                          // nonvis
  72     false,                      // offset_is_from_end
  73     true                        // only_if_ref
  74   },
  75   {
  76     "__init_array_end",         // name
  77     ".init_array",              // output_section
  78     0,                          // value
  79     0,                          // size
  80     elfcpp::STT_NOTYPE,         // type
  81     elfcpp::STB_GLOBAL,         // binding
  82     elfcpp::STV_HIDDEN,         // visibility
  83     0,                          // nonvis
  84     true,                       // offset_is_from_end
  85     true                        // only_if_ref
  86   },
  87   {
  88     "__fini_array_start",       // name
  89     ".fini_array",              // output_section
  90     0,                          // value
  91     0,                          // size
  92     elfcpp::STT_NOTYPE,         // type
  93     elfcpp::STB_GLOBAL,         // binding
  94     elfcpp::STV_HIDDEN,         // visibility
  95     0,                          // nonvis
  96     false,                      // offset_is_from_end
  97     true                        // only_if_ref
  98   },
  99   {
 100     "__fini_array_end",         // name
 101     ".fini_array",              // output_section
 102     0,                          // value
 103     0,                          // size
 104     elfcpp::STT_NOTYPE,         // type
 105     elfcpp::STB_GLOBAL,         // binding
 106     elfcpp::STV_HIDDEN,         // visibility
 107     0,                          // nonvis
 108     true,                       // offset_is_from_end
 109     true                        // only_if_ref
 110   }
 111 };
 112
 113 const int in_section_count = sizeof in_section / sizeof in_section[0];
 114
 115 const Define_symbol_in_segment in_segment[] =
 116 {
 117   {
 118     "__executable_start",       // name
 119     elfcpp::PT_LOAD,            // segment_type
 120     elfcpp::PF(0),              // segment_flags_set
 121     elfcpp::PF(0),              // segment_flags_clear
 122     0,                          // value
 123     0,                          // size
 124     elfcpp::STT_NOTYPE,         // type
 125     elfcpp::STB_GLOBAL,         // binding
 126     elfcpp::STV_DEFAULT,        // visibility
 127     0,                          // nonvis
 128     Symbol::SEGMENT_START,      // offset_from_base
 129     true                        // only_if_ref
 130   },
 131   {
 132     "etext",                    // name
 133     elfcpp::PT_LOAD,            // segment_type
 134     elfcpp::PF_X,               // segment_flags_set
 135     elfcpp::PF_W,               // segment_flags_clear
 136     0,                          // value
 137     0,                          // size
 138     elfcpp::STT_NOTYPE,         // type
 139     elfcpp::STB_GLOBAL,         // binding
 140     elfcpp::STV_DEFAULT,        // visibility
 141     0,                          // nonvis
 142     Symbol::SEGMENT_END,        // offset_from_base
 143     true                        // only_if_ref
 144   },
 145   {
 146     "_etext",                   // name
 147     elfcpp::PT_LOAD,            // segment_type
 148     elfcpp::PF_X,               // segment_flags_set
 149     elfcpp::PF_W,               // segment_flags_clear
 150     0,                          // value
 151     0,                          // size
 152     elfcpp::STT_NOTYPE,         // type
 153     elfcpp::STB_GLOBAL,         // binding
 154     elfcpp::STV_DEFAULT,        // visibility
 155     0,                          // nonvis
 156     Symbol::SEGMENT_END,        // offset_from_base
 157     true                        // only_if_ref
 158   },
 159   {
 160     "__etext",                  // name
 161     elfcpp::PT_LOAD,            // segment_type
 162     elfcpp::PF_X,               // segment_flags_set
 163     elfcpp::PF_W,               // segment_flags_clear
 164     0,                          // value
 165     0,                          // size
 166     elfcpp::STT_NOTYPE,         // type
 167     elfcpp::STB_GLOBAL,         // binding
 168     elfcpp::STV_DEFAULT,        // visibility
 169     0,                          // nonvis
 170     Symbol::SEGMENT_END,        // offset_from_base
 171     true                        // only_if_ref
 172   },
 173   {
 174     "_edata",                   // name
 175     elfcpp::PT_LOAD,            // segment_type
 176     elfcpp::PF_W,               // segment_flags_set
 177     elfcpp::PF(0),              // segment_flags_clear
 178     0,                          // value
 179     0,                          // size
 180     elfcpp::STT_NOTYPE,         // type
 181     elfcpp::STB_GLOBAL,         // binding
 182     elfcpp::STV_DEFAULT,        // visibility
 183     0,                          // nonvis
 184     Symbol::SEGMENT_BSS,        // offset_from_base
 185     false                       // only_if_ref
 186   },
 187   {
 188     "edata",                    // name
 189     elfcpp::PT_LOAD,            // segment_type
 190     elfcpp::PF_W,               // segment_flags_set
 191     elfcpp::PF(0),              // segment_flags_clear
 192     0,                          // value
 193     0,                          // size
 194     elfcpp::STT_NOTYPE,         // type
 195     elfcpp::STB_GLOBAL,         // binding
 196     elfcpp::STV_DEFAULT,        // visibility
 197     0,                          // nonvis
 198     Symbol::SEGMENT_BSS,        // offset_from_base
 199     true                        // only_if_ref
 200   },
 201   {
 202     "__bss_start",              // name
 203     elfcpp::PT_LOAD,            // segment_type
 204     elfcpp::PF_W,               // segment_flags_set
 205     elfcpp::PF(0),              // segment_flags_clear
 206     0,                          // value
 207     0,                          // size
 208     elfcpp::STT_NOTYPE,         // type
 209     elfcpp::STB_GLOBAL,         // binding
 210     elfcpp::STV_DEFAULT,        // visibility
 211     0,                          // nonvis
 212     Symbol::SEGMENT_BSS,        // offset_from_base
 213     false                       // only_if_ref
 214   },
 215   {
 216     "_end",                     // name
 217     elfcpp::PT_LOAD,            // segment_type
 218     elfcpp::PF_W,               // segment_flags_set
 219     elfcpp::PF(0),              // segment_flags_clear
 220     0,                          // value
 221     0,                          // size
 222     elfcpp::STT_NOTYPE,         // type
 223     elfcpp::STB_GLOBAL,         // binding
 224     elfcpp::STV_DEFAULT,        // visibility
 225     0,                          // nonvis
 226     Symbol::SEGMENT_END,        // offset_from_base
 227     false                       // only_if_ref
 228   },
 229   {
 230     "end",                      // name
 231     elfcpp::PT_LOAD,            // segment_type
 232     elfcpp::PF_W,               // segment_flags_set
 233     elfcpp::PF(0),              // segment_flags_clear
 234     0,                          // value
 235     0,                          // size
 236     elfcpp::STT_NOTYPE,         // type
 237     elfcpp::STB_GLOBAL,         // binding
 238     elfcpp::STV_DEFAULT,        // visibility
 239     0,                          // nonvis
 240     Symbol::SEGMENT_END,        // offset_from_base
 241     false                       // only_if_ref
 242   }
 243 };
 244
 245 const int in_segment_count = sizeof in_segment / sizeof in_segment[0];
 246
 247 } // End anonymous namespace.
 248
 249 namespace gold
 250 {
 251
 252 void
 253 define_standard_symbols(Symbol_table* symtab, const Layout* layout)
 254 {
 255   bool saw_sections_clause = layout->script_options()->saw_sections_clause();
 256   symtab->define_symbols(layout, in_section_count, in_section,
 257                          saw_sections_clause);
 258   symtab->define_symbols(layout, in_segment_count, in_segment,
 259                          saw_sections_clause);
 260 }
 261
 262 } // End namespace gold.