ld/scripttempl/elf_chaos.sc

   1 #
   2 # Unusual variables checked by this code:
   3 #       NOP - four byte opcode for no-op (defaults to 0)
   4 #       NO_SMALL_DATA - no .sbss/.sbss2/.sdata/.sdata2 sections if not
   5 #               empty.
   6 #       DATA_ADDR - if end-of-text-plus-one-page isn't right for data start
   7 #       INITIAL_READONLY_SECTIONS - at start of text segment
   8 #       OTHER_READONLY_SECTIONS - other than .text .init .rodata ...
   9 #               (e.g., .PARISC.milli)
  10 #       OTHER_TEXT_SECTIONS - these get put in .text when relocating
  11 #       OTHER_READWRITE_SECTIONS - other than .data .bss .ctors .sdata ...
  12 #               (e.g., .PARISC.global)
  13 #       OTHER_BSS_SECTIONS - other than .bss .sbss ...
  14 #       OTHER_SECTIONS - at the end
  15 #       EXECUTABLE_SYMBOLS - symbols that must be defined for an
  16 #               executable (e.g., _DYNAMIC_LINK)
  17 #       TEXT_START_SYMBOLS - symbols that appear at the start of the
  18 #               .text section.
  19 #       DATA_START_SYMBOLS - symbols that appear at the start of the
  20 #               .data section.
  21 #       OTHER_GOT_SYMBOLS - symbols defined just before .got.
  22 #       OTHER_GOT_SECTIONS - sections just after .got.
  23 #       OTHER_SDATA_SECTIONS - sections just after .sdata.
  24 #       OTHER_BSS_SYMBOLS - symbols that appear at the start of the
  25 #               .bss section besides __bss_start.
  26 #       DATA_PLT - .plt should be in data segment, not text segment.
  27 #       BSS_PLT - .plt should be in bss segment
  28 #       TEXT_DYNAMIC - .dynamic in text segment, not data segment.
  29 #       EMBEDDED - whether this is for an embedded system.
  30 #       SHLIB_TEXT_START_ADDR - if set, add to SIZEOF_HEADERS to set
  31 #               start address of shared library.
  32 #       INPUT_FILES - INPUT command of files to always include
  33 #       WRITABLE_RODATA - if set, the .rodata section should be writable
  34 #       INIT_START, INIT_END -  statements just before and just after
  35 #       combination of .init sections.
  36 #       FINI_START, FINI_END - statements just before and just after
  37 #       combination of .fini sections.
  38 #       STACK_ADDR - start of a .stack section.
  39 #       OTHER_END_SYMBOLS - symbols to place right at the end of the script.
  40 #
  41 # When adding sections, do note that the names of some sections are used
  42 # when specifying the start address of the next.
  43 #
  44
  45 #  Many sections come in three flavours.  There is the 'real' section,
  46 #  like ".data".  Then there are the per-procedure or per-variable
  47 #  sections, generated by -ffunction-sections and -fdata-sections in GCC,
  48 #  and useful for --gc-sections, which for a variable "foo" might be
  49 #  ".data.foo".  Then there are the linkonce sections, for which the linker
  50 #  eliminates duplicates, which are named like ".gnu.linkonce.d.foo".
  51 #  The exact correspondences are:
  52 #
  53 #  Section      Linkonce section
  54 #  .text        .gnu.linkonce.t.foo
  55 #  .rodata      .gnu.linkonce.r.foo
  56 #  .data        .gnu.linkonce.d.foo
  57 #  .bss         .gnu.linkonce.b.foo
  58 #  .sdata       .gnu.linkonce.s.foo
  59 #  .sbss        .gnu.linkonce.sb.foo
  60 #  .sdata2      .gnu.linkonce.s2.foo
  61 #  .sbss2       .gnu.linkonce.sb2.foo
  62 #  .debug_info  .gnu.linkonce.wi.foo
  63 #
  64 #  Each of these can also have corresponding .rel.* and .rela.* sections.
  65
  66 test -z "$ENTRY" && ENTRY=_start
  67 test -z "${BIG_OUTPUT_FORMAT}" && BIG_OUTPUT_FORMAT=${OUTPUT_FORMAT}
  68 test -z "${LITTLE_OUTPUT_FORMAT}" && LITTLE_OUTPUT_FORMAT=${OUTPUT_FORMAT}
  69 if [ -z "$MACHINE" ]; then OUTPUT_ARCH=${ARCH}; else OUTPUT_ARCH=${ARCH}:${MACHINE}; fi
  70 test -z "${ELFSIZE}" && ELFSIZE=32
  71 test -z "${ALIGNMENT}" && ALIGNMENT="${ELFSIZE} / 8"
  72 test "$LD_FLAG" = "N" && DATA_ADDR=.
  73 INTERP=".interp       ${RELOCATING-0} : { *(.interp) }"
  74 PLT=".plt          ${RELOCATING-0} : { *(.plt) }"
  75 DYNAMIC=".dynamic      ${RELOCATING-0} : { *(.dynamic) }"
  76 RODATA=".rodata       ${RELOCATING-0} : { *(.rodata${RELOCATING+ .rodata.* .gnu.linkonce.r.*}) }"
  77 if test -z "${NO_SMALL_DATA}"; then
  78   SBSS=".sbss         ${RELOCATING-0} :
  79   {
  80     ${RELOCATING+PROVIDE (__sbss_start = .);}
  81     ${RELOCATING+PROVIDE (___sbss_start = .);}
  82     *(.dynsbss)
  83     *(.sbss${RELOCATING+ .sbss.* .gnu.linkonce.sb.*})
  84     *(.scommon)
  85     ${RELOCATING+PROVIDE (__sbss_end = .);}
  86     ${RELOCATING+PROVIDE (___sbss_end = .);}
  87   }"
  88   SBSS2=".sbss2        ${RELOCATING-0} : { *(.sbss2${RELOCATING+ .sbss2.* .gnu.linkonce.sb2.*}) }"
  89   SDATA="/* We want the small data sections together, so single-instruction offsets
  90      can access them all, and initialized data all before uninitialized, so
  91      we can shorten the on-disk segment size.  */
  92   .sdata        ${RELOCATING-0} :
  93   {
  94     ${RELOCATING+${SDATA_START_SYMBOLS}}
  95     *(.sdata${RELOCATING+ .sdata.* .gnu.linkonce.s.*})
  96   }"
  97   SDATA2=".sdata2       ${RELOCATING-0} : { *(.sdata2${RELOCATING+ .sdata2.* .gnu.linkonce.s2.*}) }"
  98   REL_SDATA=".rel.sdata    ${RELOCATING-0} : { *(.rel.sdata${RELOCATING+ .rel.sdata.* .rel.gnu.linkonce.s.*}) }
  99   .rela.sdata   ${RELOCATING-0} : { *(.rela.sdata${RELOCATING+ .rela.sdata.* .rela.gnu.linkonce.s.*}) }"
 100   REL_SBSS=".rel.sbss     ${RELOCATING-0} : { *(.rel.sbss${RELOCATING+ .rel.sbss.* .rel.gnu.linkonce.sb.*}) }
 101   .rela.sbss    ${RELOCATING-0} : { *(.rela.sbss${RELOCATING+ .rela.sbss.* .rela.gnu.linkonce.sb.*}) }"
 102   REL_SDATA2=".rel.sdata2   ${RELOCATING-0} : { *(.rel.sdata2${RELOCATING+ .rel.sdata2.* .rel.gnu.linkonce.s2.*}) }
 103   .rela.sdata2  ${RELOCATING-0} : { *(.rela.sdata2${RELOCATING+ .rela.sdata2.* .rela.gnu.linkonce.s2.*}) }"
 104   REL_SBSS2=".rel.sbss2    ${RELOCATING-0} : { *(.rel.sbss2${RELOCATING+ .rel.sbss2.* .rel.gnu.linkonce.sb2.*}) }
 105   .rela.sbss2   ${RELOCATING-0} : { *(.rela.sbss2${RELOCATING+ .rela.sbss2.* .rela.gnu.linkonce.sb2.*}) }"
 106 fi
 107 CTOR="
 108     ${CONSTRUCTING+${CTOR_START}}
 109     /* gcc uses crtbegin.o to find the start of
 110        the constructors, so we make sure it is
 111        first.  Because this is a wildcard, it
 112        doesn't matter if the user does not
 113        actually link against crtbegin.o; the
 114        linker won't look for a file to match a
 115        wildcard.  The wildcard also means that it
 116        doesn't matter which directory crtbegin.o
 117        is in.  */
 118
 119     KEEP (*crtbegin*.o(.ctors))
 120
 121     /* We don't want to include the .ctor section from
 122        from the crtend.o file until after the sorted ctors.
 123        The .ctor section from the crtend file contains the
 124        end of ctors marker and it must be last */
 125
 126     KEEP (*(EXCLUDE_FILE (*crtend*.o $OTHER_EXCLUDE_FILES) .ctors))
 127     KEEP (*(SORT(.ctors.*)))
 128     KEEP (*(.ctors))
 129     ${CONSTRUCTING+${CTOR_END}}
 130 "
 131 DTOR="
 132     ${CONSTRUCTING+${DTOR_START}}
 133     KEEP (*crtbegin*.o(.dtors))
 134     KEEP (*(EXCLUDE_FILE (*crtend*.o $OTHER_EXCLUDE_FILES) .dtors))
 135     KEEP (*(SORT(.dtors.*)))
 136     KEEP (*(.dtors))
 137     ${CONSTRUCTING+${DTOR_END}}
 138 "
 139 STACK="  .stack        ${RELOCATING-0}${RELOCATING+${STACK_ADDR}} :
 140   {
 141     ${RELOCATING+_stack = .;}
 142     *(.stack)
 143   }"
 144
 145 test -z "${TEXT_BASE_ADDRESS}" && TEXT_BASE_ADDRESS="${TEXT_START_ADDR}"
 146
 147 cat <<EOF
 148 OUTPUT_FORMAT("${OUTPUT_FORMAT}", "${BIG_OUTPUT_FORMAT}",
 149               "${LITTLE_OUTPUT_FORMAT}")
 150 OUTPUT_ARCH(${OUTPUT_ARCH})
 151 ENTRY(${ENTRY})
 152
 153 ${RELOCATING+${LIB_SEARCH_DIRS}}
 154 ${RELOCATING+/* Do we need any of these for elf?
 155    __DYNAMIC = 0; ${STACKZERO+${STACKZERO}} ${SHLIB_PATH+${SHLIB_PATH}}  */}
 156 ${RELOCATING+${EXECUTABLE_SYMBOLS}}
 157 ${RELOCATING+${INPUT_FILES}}
 158 ${RELOCATING- /* For some reason, the Solaris linker makes bad executables
 159   if gld -r is used and the intermediate file has sections starting
 160   at non-zero addresses.  Could be a Solaris ld bug, could be a GNU ld
 161   bug.  But for now assigning the zero vmas works.  */}
 162
 163 SECTIONS
 164 {
 165   /* Read-only sections, merged into text segment: */
 166   ${CREATE_SHLIB-${RELOCATING+. = ${TEXT_BASE_ADDRESS};}}
 167   ${CREATE_SHLIB+${RELOCATING+. = ${SHLIB_TEXT_START_ADDR:-0};}}
 168   ${CREATE_SHLIB-${INTERP}}
 169   ${INITIAL_READONLY_SECTIONS}
 170   ${TEXT_DYNAMIC+${DYNAMIC}}
 171   .hash         ${RELOCATING-0} : { *(.hash) }
 172   .dynsym       ${RELOCATING-0} : { *(.dynsym) }
 173   .dynstr       ${RELOCATING-0} : { *(.dynstr) }
 174   .gnu.version  ${RELOCATING-0} : { *(.gnu.version) }
 175   .gnu.version_d ${RELOCATING-0}: { *(.gnu.version_d) }
 176   .gnu.version_r ${RELOCATING-0}: { *(.gnu.version_r) }
 177
 178 EOF
 179 if [ "x$COMBRELOC" = x ]; then
 180   COMBRELOCCAT=cat
 181 else
 182   COMBRELOCCAT="cat > $COMBRELOC"
 183 fi
 184 eval $COMBRELOCCAT <<EOF
 185   .rel.init     ${RELOCATING-0} : { *(.rel.init) }
 186   .rela.init    ${RELOCATING-0} : { *(.rela.init) }
 187   .rel.text     ${RELOCATING-0} : { *(.rel.text${RELOCATING+ .rel.text.* .rel.gnu.linkonce.t.*}) }
 188   .rela.text    ${RELOCATING-0} : { *(.rela.text${RELOCATING+ .rela.text.* .rela.gnu.linkonce.t.*}) }
 189   .rel.fini     ${RELOCATING-0} : { *(.rel.fini) }
 190   .rela.fini    ${RELOCATING-0} : { *(.rela.fini) }
 191   .rel.rodata   ${RELOCATING-0} : { *(.rel.rodata${RELOCATING+ .rel.rodata.* .rel.gnu.linkonce.r.*}) }
 192   .rela.rodata  ${RELOCATING-0} : { *(.rela.rodata${RELOCATING+ .rela.rodata.* .rela.gnu.linkonce.r.*}) }
 193   ${OTHER_READONLY_RELOC_SECTIONS}
 194   .rel.data     ${RELOCATING-0} : { *(.rel.data${RELOCATING+ .rel.data.* .rel.gnu.linkonce.d.*}) }
 195   .rela.data    ${RELOCATING-0} : { *(.rela.data${RELOCATING+ .rela.data.* .rela.gnu.linkonce.d.*}) }
 196   .rel.ctors    ${RELOCATING-0} : { *(.rel.ctors) }
 197   .rela.ctors   ${RELOCATING-0} : { *(.rela.ctors) }
 198   .rel.dtors    ${RELOCATING-0} : { *(.rel.dtors) }
 199   .rela.dtors   ${RELOCATING-0} : { *(.rela.dtors) }
 200   .rel.got      ${RELOCATING-0} : { *(.rel.got) }
 201   .rela.got     ${RELOCATING-0} : { *(.rela.got) }
 202   ${OTHER_GOT_RELOC_SECTIONS}
 203   ${REL_SDATA}
 204   ${REL_SBSS}
 205   ${REL_SDATA2}
 206   ${REL_SBSS2}
 207   .rel.bss      ${RELOCATING-0} : { *(.rel.bss${RELOCATING+ .rel.bss.* .rel.gnu.linkonce.b.*}) }
 208   .rela.bss     ${RELOCATING-0} : { *(.rela.bss${RELOCATING+ .rela.bss.* .rela.gnu.linkonce.b.*}) }
 209 EOF
 210 if [ -n "$COMBRELOC" ]; then
 211 cat <<EOF
 212   .rel.dyn      ${RELOCATING-0} :
 213     {
 214 EOF
 215 sed -e '/^[     ]*[{}][         ]*$/d;/:[       ]*$/d;/\.rela\./d;s/^.*: { *\(.*\)}$/      \1/' $COMBRELOC
 216 cat <<EOF
 217     }
 218   .rela.dyn     ${RELOCATING-0} :
 219     {
 220 EOF
 221 sed -e '/^[     ]*[{}][         ]*$/d;/:[       ]*$/d;/\.rel\./d;s/^.*: { *\(.*\)}/      \1/' $COMBRELOC
 222 cat <<EOF
 223     }
 224 EOF
 225 fi
 226 cat <<EOF
 227   . = ALIGN(0x1000);
 228   .rel.plt      ${RELOCATING-0} : { *(.rel.plt) }
 229   .rela.plt     ${RELOCATING-0} : { *(.rela.plt) }
 230   ${OTHER_PLT_RELOC_SECTIONS}
 231   ${DATA_PLT-${BSS_PLT-${PLT}}}
 232   .text         ${RELOCATING-0} :
 233   {
 234     ${RELOCATING+${TEXT_START_SYMBOLS}}
 235     *(.text .stub${RELOCATING+ .text.* .gnu.linkonce.t.*})
 236     /* .gnu.warning sections are handled specially by elf32.em.  */
 237     *(.gnu.warning)
 238     ${RELOCATING+${OTHER_TEXT_SECTIONS}}
 239   } =${NOP-0}
 240   .fini         ${RELOCATING-0} :
 241   {
 242     ${RELOCATING+${FINI_START}}
 243     KEEP (*(.fini))
 244     ${RELOCATING+${FINI_END}}
 245   } =${NOP-0}
 246   ${RELOCATING+PROVIDE (__etext = .);}
 247   ${RELOCATING+PROVIDE (_etext = .);}
 248   ${RELOCATING+PROVIDE (etext = .);}
 249   . = ALIGN(0x1000);
 250   ${CREATE_SHLIB-${SDATA2}}
 251   ${CREATE_SHLIB-${SBSS2}}
 252   ${OTHER_READONLY_SECTIONS}
 253   .eh_frame_hdr : { *(.eh_frame_hdr) }
 254
 255   . = ALIGN(0x1000);
 256   .data         ${RELOCATING-0} :
 257   {
 258     *(.rodata .rodata.*)
 259     *(.rodata1)
 260     *(.gnu.linkonce.r.*)
 261     ${RELOCATING+${DATA_START_SYMBOLS}}
 262     *(.data${RELOCATING+ .data.* .gnu.linkonce.d.*})
 263     ${CONSTRUCTING+SORT(CONSTRUCTORS)}
 264     KEEP (*(.eh_frame))
 265     *(.gcc_except_table)
 266     ${CTOR}
 267     ${DTOR}
 268     KEEP (*(.jcr))
 269   }
 270   .data1        ${RELOCATING-0} : { *(.data1) }
 271   . = ALIGN(0x1000);
 272   .gcc_except_table ${RELOCATING-0} : { *(.gcc_except_table) }
 273   ${WRITABLE_RODATA+${RODATA}}
 274   ${OTHER_READWRITE_SECTIONS}
 275   ${TEXT_DYNAMIC-${DYNAMIC}}
 276   ${DATA_PLT+${PLT}}
 277   ${RELOCATING+${OTHER_GOT_SYMBOLS}}
 278   .got          ${RELOCATING-0} : { *(.got.plt) *(.got) }
 279   ${OTHER_GOT_SECTIONS}
 280   ${CREATE_SHLIB+${SDATA2}}
 281   ${CREATE_SHLIB+${SBSS2}}
 282   ${SDATA}
 283   ${OTHER_SDATA_SECTIONS}
 284   ${RELOCATING+_edata = .;}
 285   ${RELOCATING+PROVIDE (edata = .);}
 286   ${RELOCATING+__bss_start = .;}
 287   ${RELOCATING+${OTHER_BSS_SYMBOLS}}
 288   ${SBSS}
 289   ${BSS_PLT+${PLT}}
 290   . = ALIGN(0x1000);
 291   .bss          ${RELOCATING-0} :
 292   {
 293    *(.dynbss)
 294    *(.bss${RELOCATING+ .bss.* .gnu.linkonce.b.*})
 295    *(COMMON)
 296    /* Align here to ensure that the .bss section occupies space up to
 297       _end.  Align after .bss to ensure correct alignment even if the
 298       .bss section disappears because there are no input sections.  */
 299    ${RELOCATING+. = ALIGN(${ALIGNMENT});}
 300   }
 301   ${OTHER_BSS_SECTIONS}
 302   ${RELOCATING+. = ALIGN(${ALIGNMENT});}
 303   ${RELOCATING+_end = .;}
 304   ${RELOCATING+${OTHER_BSS_END_SYMBOLS}}
 305   ${RELOCATING+PROVIDE (end = .);}
 306
 307   /* Stabs debugging sections.  */
 308   . = ALIGN(0x1000);
 309   .stab          0 : { *(.stab) }
 310   .stabstr       0 : { *(.stabstr) }
 311   .stab.excl     0 : { *(.stab.excl) }
 312   .stab.exclstr  0 : { *(.stab.exclstr) }
 313   .stab.index    0 : { *(.stab.index) }
 314   .stab.indexstr 0 : { *(.stab.indexstr) }
 315
 316   . = ALIGN(0x1000);
 317   .comment       0 : { *(.comment) }
 318
 319   /* DWARF debug sections.
 320      Symbols in the DWARF debugging sections are relative to the beginning
 321      of the section so we begin them at 0.  */
 322
 323   /* DWARF 1 */
 324   .debug          0 : { *(.debug) }
 325   .line           0 : { *(.line) }
 326
 327   /* GNU DWARF 1 extensions */
 328   .debug_srcinfo  0 : { *(.debug_srcinfo) }
 329   .debug_sfnames  0 : { *(.debug_sfnames) }
 330
 331   /* DWARF 1.1 and DWARF 2 */
 332   .debug_aranges  0 : { *(.debug_aranges) }
 333   .debug_pubnames 0 : { *(.debug_pubnames) }
 334
 335   /* DWARF 2 */
 336   .debug_info     0 : { *(.debug_info .gnu.linkonce.wi.*) }
 337   .debug_abbrev   0 : { *(.debug_abbrev) }
 338   .debug_line     0 : { *(.debug_line) }
 339   .debug_frame    0 : { *(.debug_frame) }
 340   .debug_str      0 : { *(.debug_str) }
 341   .debug_loc      0 : { *(.debug_loc) }
 342   .debug_macinfo  0 : { *(.debug_macinfo) }
 343
 344   /* SGI/MIPS DWARF 2 extensions */
 345   .debug_weaknames 0 : { *(.debug_weaknames) }
 346   .debug_funcnames 0 : { *(.debug_funcnames) }
 347   .debug_typenames 0 : { *(.debug_typenames) }
 348   .debug_varnames  0 : { *(.debug_varnames) }
 349
 350   ${STACK_ADDR+${STACK}}
 351   ${OTHER_SECTIONS}
 352   ${RELOCATING+${OTHER_END_SYMBOLS}}
 353 }
 354 EOF