ld/scripttempl/elf.sc

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