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 #       BSS_PLT - .plt should be in bss segment
  25 #       TEXT_DYNAMIC - .dynamic in text segment, not data segment.
  26 #       EMBEDDED - whether this is for an embedded system.
  27 #       SHLIB_TEXT_START_ADDR - if set, add to SIZEOF_HEADERS to set
  28 #               start address of shared library.
  29 #       INPUT_FILES - INPUT command of files to always include
  30 #       WRITABLE_RODATA - if set, the .rodata section should be writable
  31 #       INIT_START, INIT_END -  statements just before and just after
  32 #       combination of .init sections.
  33 #       FINI_START, FINI_END - statements just before and just after
  34 #       combination of .fini sections.
  35 #
  36 # When adding sections, do note that the names of some sections are used
  37 # when specifying the start address of the next.
  38 #
  39
  40 test -z "$ENTRY" && ENTRY=_start
  41 test -z "${BIG_OUTPUT_FORMAT}" && BIG_OUTPUT_FORMAT=${OUTPUT_FORMAT}
  42 test -z "${LITTLE_OUTPUT_FORMAT}" && LITTLE_OUTPUT_FORMAT=${OUTPUT_FORMAT}
  43 if [ -z "$MACHINE" ]; then OUTPUT_ARCH=${ARCH}; else OUTPUT_ARCH=${ARCH}:${MACHINE}; fi
  44 test -z "${ELFSIZE}" && ELFSIZE=32
  45 test -z "${ALIGNMENT}" && ALIGNMENT="${ELFSIZE} / 8"
  46 test "$LD_FLAG" = "N" && DATA_ADDR=.
  47 INTERP=".interp   ${RELOCATING-0} : { *(.interp)        }"
  48 PLT=".plt    ${RELOCATING-0} : { *(.plt)        }"
  49 DYNAMIC=".dynamic     ${RELOCATING-0} : { *(.dynamic) }"
  50 RODATA=".rodata ${RELOCATING-0} : { *(.rodata) ${RELOCATING+*(.rodata.*)} ${RELOCATING+*(.gnu.linkonce.r*)} }"
  51 SBSS2=".sbss2 ${RELOCATING-0} : { *(.sbss2) }"
  52 SDATA2=".sdata2 ${RELOCATING-0} : { *(.sdata2) }"
  53 CTOR=".ctors ${CONSTRUCTING-0} :
  54   {
  55     ${CONSTRUCTING+${CTOR_START}}
  56     /* gcc uses crtbegin.o to find the start of
  57        the constructors, so we make sure it is
  58        first.  Because this is a wildcard, it
  59        doesn't matter if the user does not
  60        actually link against crtbegin.o; the
  61        linker won't look for a file to match a
  62        wildcard.  The wildcard also means that it
  63        doesn't matter which directory crtbegin.o
  64        is in.  */
  65
  66     KEEP (*crtbegin.o(.ctors))
  67
  68     /* We don't want to include the .ctor section from
  69        from the crtend.o file until after the sorted ctors.
  70        The .ctor section from the crtend file contains the
  71        end of ctors marker and it must be last */
  72
  73     KEEP (*(EXCLUDE_FILE (*crtend.o $OTHER_EXCLUDE_FILES) .ctors))
  74     KEEP (*(SORT(.ctors.*)))
  75     KEEP (*(.ctors))
  76     ${CONSTRUCTING+${CTOR_END}}
  77   }"
  78
  79 DTOR=" .dtors       ${CONSTRUCTING-0} :
  80   {
  81     ${CONSTRUCTING+${DTOR_START}}
  82     KEEP (*crtbegin.o(.dtors))
  83     KEEP (*(EXCLUDE_FILE (*crtend.o $OTHER_EXCLUDE_FILES) .dtors))
  84     KEEP (*(SORT(.dtors.*)))
  85     KEEP (*(.dtors))
  86     ${CONSTRUCTING+${DTOR_END}}
  87   }"
  88
  89 # if this is for an embedded system, don't add SIZEOF_HEADERS.
  90 if [ -z "$EMBEDDED" ]; then
  91    test -z "${TEXT_BASE_ADDRESS}" && TEXT_BASE_ADDRESS="${TEXT_START_ADDR} + SIZEOF_HEADERS"
  92 else
  93    test -z "${TEXT_BASE_ADDRESS}" && TEXT_BASE_ADDRESS="${TEXT_START_ADDR}"
  94 fi
  95
  96 cat <<EOF
  97 OUTPUT_FORMAT("${OUTPUT_FORMAT}", "${BIG_OUTPUT_FORMAT}",
  98               "${LITTLE_OUTPUT_FORMAT}")
  99 OUTPUT_ARCH(${OUTPUT_ARCH})
 100 ENTRY(${ENTRY})
 101
 102 ${RELOCATING+${LIB_SEARCH_DIRS}}
 103 ${RELOCATING+/* Do we need any of these for elf?
 104    __DYNAMIC = 0; ${STACKZERO+${STACKZERO}} ${SHLIB_PATH+${SHLIB_PATH}}  */}
 105 ${RELOCATING+${EXECUTABLE_SYMBOLS}}
 106 ${RELOCATING+${INPUT_FILES}}
 107 ${RELOCATING- /* For some reason, the Solaris linker makes bad executables
 108   if gld -r is used and the intermediate file has sections starting
 109   at non-zero addresses.  Could be a Solaris ld bug, could be a GNU ld
 110   bug.  But for now assigning the zero vmas works.  */}
 111
 112 SECTIONS
 113 {
 114   /* Read-only sections, merged into text segment: */
 115   ${CREATE_SHLIB-${RELOCATING+. = ${TEXT_BASE_ADDRESS};}}
 116   ${CREATE_SHLIB+${RELOCATING+. = ${SHLIB_TEXT_START_ADDR:-0} + SIZEOF_HEADERS;}}
 117   ${CREATE_SHLIB-${INTERP}}
 118   ${INITIAL_READONLY_SECTIONS}
 119   ${TEXT_DYNAMIC+${DYNAMIC}}
 120   .hash        ${RELOCATING-0} : { *(.hash)             }
 121   .dynsym      ${RELOCATING-0} : { *(.dynsym)           }
 122   .dynstr      ${RELOCATING-0} : { *(.dynstr)           }
 123   .gnu.version ${RELOCATING-0} : { *(.gnu.version)      }
 124   .gnu.version_d ${RELOCATING-0} : { *(.gnu.version_d)  }
 125   .gnu.version_r ${RELOCATING-0} : { *(.gnu.version_r)  }
 126
 127   .rel.text    ${RELOCATING-0} :
 128     {
 129       *(.rel.text)
 130       ${RELOCATING+*(.rel.text.*)}
 131       ${RELOCATING+*(.rel.gnu.linkonce.t*)}
 132     }
 133   .rela.text   ${RELOCATING-0} :
 134     {
 135       *(.rela.text)
 136       ${RELOCATING+*(.rela.text.*)}
 137       ${RELOCATING+*(.rela.gnu.linkonce.t*)}
 138     }
 139   .rel.init    ${RELOCATING-0} : { *(.rel.init) }
 140   .rela.init   ${RELOCATING-0} : { *(.rela.init)        }
 141   .rel.fini    ${RELOCATING-0} : { *(.rel.fini) }
 142   .rela.fini   ${RELOCATING-0} : { *(.rela.fini)        }
 143   .rel.rodata  ${RELOCATING-0} :
 144     {
 145       *(.rel.rodata)
 146       ${RELOCATING+*(.rel.rodata.*)}
 147       ${RELOCATING+*(.rel.gnu.linkonce.r*)}
 148     }
 149   .rela.rodata ${RELOCATING-0} :
 150     {
 151       *(.rela.rodata)
 152       ${RELOCATING+*(.rela.rodata.*)}
 153       ${RELOCATING+*(.rela.gnu.linkonce.r*)}
 154     }
 155   ${OTHER_READONLY_RELOC_SECTIONS}
 156   .rel.data    ${RELOCATING-0} :
 157     {
 158       *(.rel.data)
 159       ${RELOCATING+*(.rel.data.*)}
 160       ${RELOCATING+*(.rel.gnu.linkonce.d*)}
 161     }
 162   .rela.data   ${RELOCATING-0} :
 163     {
 164       *(.rela.data)
 165       ${RELOCATING+*(.rela.data.*)}
 166       ${RELOCATING+*(.rela.gnu.linkonce.d*)}
 167     }
 168   .rel.ctors   ${RELOCATING-0} : { *(.rel.ctors)        }
 169   .rela.ctors  ${RELOCATING-0} : { *(.rela.ctors)       }
 170   .rel.dtors   ${RELOCATING-0} : { *(.rel.dtors)        }
 171   .rela.dtors  ${RELOCATING-0} : { *(.rela.dtors)       }
 172   .rel.got     ${RELOCATING-0} : { *(.rel.got)          }
 173   .rela.got    ${RELOCATING-0} : { *(.rela.got)         }
 174   ${OTHER_GOT_RELOC_SECTIONS}
 175   .rel.sdata   ${RELOCATING-0} :
 176     {
 177       *(.rel.sdata)
 178       ${RELOCATING+*(.rel.sdata.*)}
 179       ${RELOCATING+*(.rel.gnu.linkonce.s*)}
 180     }
 181   .rela.sdata   ${RELOCATING-0} :
 182     {
 183       *(.rela.sdata)
 184       ${RELOCATING+*(.rela.sdata.*)}
 185       ${RELOCATING+*(.rela.gnu.linkonce.s*)}
 186     }
 187   .rel.sbss    ${RELOCATING-0} : { *(.rel.sbss)         }
 188   .rela.sbss   ${RELOCATING-0} : { *(.rela.sbss)        }
 189   .rel.sdata2  ${RELOCATING-0} : { *(.rel.sdata2)       }
 190   .rela.sdata2 ${RELOCATING-0} : { *(.rela.sdata2)      }
 191   .rel.sbss2   ${RELOCATING-0} : { *(.rel.sbss2)        }
 192   .rela.sbss2  ${RELOCATING-0} : { *(.rela.sbss2)       }
 193   .rel.bss     ${RELOCATING-0} : { *(.rel.bss)          }
 194   .rela.bss    ${RELOCATING-0} : { *(.rela.bss)         }
 195   .rel.plt     ${RELOCATING-0} : { *(.rel.plt)          }
 196   .rela.plt    ${RELOCATING-0} : { *(.rela.plt)         }
 197   ${OTHER_PLT_RELOC_SECTIONS}
 198
 199   ${DATA_PLT-${BSS_PLT-${PLT}}}
 200   /* .text should be before .init and so on, so that -Ttext=0x1234
 201      will work.  */
 202   .text    ${RELOCATING-0} :
 203   {
 204     ${RELOCATING+${TEXT_START_SYMBOLS}}
 205     *(.text)
 206     ${RELOCATING+*(.text.*)}
 207     *(.stub)
 208     /* .gnu.warning sections are handled specially by elf32.em.  */
 209     *(.gnu.warning)
 210     ${RELOCATING+*(.gnu.linkonce.t*)}
 211     ${RELOCATING+${OTHER_TEXT_SECTIONS}}
 212   } =${NOP-0}
 213   .init        ${RELOCATING-0} :
 214   {
 215     ${INIT_START}
 216     KEEP (*(.init))
 217     ${INIT_END}
 218   } =${NOP-0}
 219   .fini    ${RELOCATING-0} :
 220   {
 221     ${FINI_START}
 222     KEEP (*(.fini))
 223     ${FINI_END}
 224   } =${NOP-0}
 225   ${RELOCATING+PROVIDE (__etext = .);}
 226   ${RELOCATING+PROVIDE (_etext = .);}
 227   ${RELOCATING+PROVIDE (etext = .);}
 228   ${WRITABLE_RODATA-${RODATA}}
 229   .rodata1 ${RELOCATING-0} : { *(.rodata1) }
 230   ${CREATE_SHLIB-${SDATA2}}
 231   ${CREATE_SHLIB-${SBSS2}}
 232   ${RELOCATING+${OTHER_READONLY_SECTIONS}}
 233
 234   /* Adjust the address for the data segment.  We want to adjust up to
 235      the same address within the page on the next page up.  */
 236   ${CREATE_SHLIB-${RELOCATING+. = ${DATA_ADDR-ALIGN(${MAXPAGESIZE}) + (. & (${MAXPAGESIZE} - 1))};}}
 237   ${CREATE_SHLIB+${RELOCATING+. = ${SHLIB_DATA_ADDR-ALIGN(${MAXPAGESIZE}) + (. & (${MAXPAGESIZE} - 1))};}}
 238
 239   .data  ${RELOCATING-0} :
 240   {
 241     ${RELOCATING+${DATA_START_SYMBOLS}}
 242     *(.data)
 243     ${RELOCATING+*(.data.*)}
 244     ${RELOCATING+*(.gnu.linkonce.d*)}
 245     ${CONSTRUCTING+SORT(CONSTRUCTORS)}
 246   }
 247   .data1 ${RELOCATING-0} : { *(.data1) }
 248   .eh_frame : { *(.eh_frame) }
 249   .gcc_except_table : { *(.gcc_except_table) }
 250   ${WRITABLE_RODATA+${RODATA}}
 251   ${RELOCATING+${OTHER_READWRITE_SECTIONS}}
 252   ${RELOCATING+${CTOR}}
 253   ${RELOCATING+${DTOR}}
 254   ${DATA_PLT+${PLT}}
 255   ${RELOCATING+${OTHER_GOT_SYMBOLS}}
 256   .got          ${RELOCATING-0} : { *(.got.plt) *(.got) }
 257   ${CREATE_SHLIB+${SDATA2}}
 258   ${CREATE_SHLIB+${SBSS2}}
 259   ${TEXT_DYNAMIC-${DYNAMIC}}
 260   /* We want the small data sections together, so single-instruction offsets
 261      can access them all, and initialized data all before uninitialized, so
 262      we can shorten the on-disk segment size.  */
 263   .sdata   ${RELOCATING-0} :
 264   {
 265     ${RELOCATING+${SDATA_START_SYMBOLS}}
 266     *(.sdata)
 267     ${RELOCATING+*(.sdata.*)}
 268     ${RELOCATING+*(.gnu.linkonce.s.*)}
 269   }
 270   ${RELOCATING+${OTHER_GOT_SECTIONS}}
 271   ${RELOCATING+_edata = .;}
 272   ${RELOCATING+PROVIDE (edata = .);}
 273   ${RELOCATING+__bss_start = .;}
 274   ${RELOCATING+${OTHER_BSS_SYMBOLS}}
 275   .sbss    ${RELOCATING-0} :
 276   {
 277     ${RELOCATING+PROVIDE (__sbss_start = .);}
 278     ${RELOCATING+PROVIDE (___sbss_start = .);}
 279     *(.dynsbss)
 280     *(.sbss)
 281     ${RELOCATING+*(.sbss.*)}
 282     *(.scommon)
 283     ${RELOCATING+PROVIDE (__sbss_end = .);}
 284     ${RELOCATING+PROVIDE (___sbss_end = .);}
 285   }
 286   ${BSS_PLT+${PLT}}
 287   .bss     ${RELOCATING-0} :
 288   {
 289    *(.dynbss)
 290    *(.bss)
 291    ${RELOCATING+*(.bss.*)}
 292    *(COMMON)
 293    /* Align here to ensure that the .bss section occupies space up to
 294       _end.  Align after .bss to ensure correct alignment even if the
 295       .bss section disappears because there are no input sections.  */
 296    ${RELOCATING+. = ALIGN(${ALIGNMENT});}
 297   }
 298   ${RELOCATING+${OTHER_BSS_SECTIONS}}
 299   ${RELOCATING+. = ALIGN(${ALIGNMENT});}
 300   ${RELOCATING+_end = .;}
 301   ${RELOCATING+${OTHER_BSS_END_SYMBOLS}}
 302   ${RELOCATING+PROVIDE (end = .);}
 303
 304   /* Stabs debugging sections.  */
 305   .stab 0 : { *(.stab) }
 306   .stabstr 0 : { *(.stabstr) }
 307   .stab.excl 0 : { *(.stab.excl) }
 308   .stab.exclstr 0 : { *(.stab.exclstr) }
 309   .stab.index 0 : { *(.stab.index) }
 310   .stab.indexstr 0 : { *(.stab.indexstr) }
 311
 312   .comment 0 : { *(.comment) }
 313
 314   /* DWARF debug sections.
 315      Symbols in the DWARF debugging sections are relative to the beginning
 316      of the section so we begin them at 0.  */
 317
 318   /* DWARF 1 */
 319   .debug          0 : { *(.debug) }
 320   .line           0 : { *(.line) }
 321
 322   /* GNU DWARF 1 extensions */
 323   .debug_srcinfo  0 : { *(.debug_srcinfo) }
 324   .debug_sfnames  0 : { *(.debug_sfnames) }
 325
 326   /* DWARF 1.1 and DWARF 2 */
 327   .debug_aranges  0 : { *(.debug_aranges) }
 328   .debug_pubnames 0 : { *(.debug_pubnames) }
 329
 330   /* DWARF 2 */
 331   .debug_info     0 : { *(.debug_info) }
 332   .debug_abbrev   0 : { *(.debug_abbrev) }
 333   .debug_line     0 : { *(.debug_line) }
 334   .debug_frame    0 : { *(.debug_frame) }
 335   .debug_str      0 : { *(.debug_str) }
 336   .debug_loc      0 : { *(.debug_loc) }
 337   .debug_macinfo  0 : { *(.debug_macinfo) }
 338
 339   /* SGI/MIPS DWARF 2 extensions */
 340   .debug_weaknames 0 : { *(.debug_weaknames) }
 341   .debug_funcnames 0 : { *(.debug_funcnames) }
 342   .debug_typenames 0 : { *(.debug_typenames) }
 343   .debug_varnames  0 : { *(.debug_varnames) }
 344
 345   ${RELOCATING+${OTHER_RELOCATING_SECTIONS}}
 346
 347   /* These must appear regardless of ${RELOCATING}.  */
 348   ${OTHER_SECTIONS}
 349 }
 350 EOF