ld/NEWS

   1 -*- text -*-
   2 * Add -z separate-code to generate separate code PT_LOAD segment.
   3
   4 * Add -z globalaudit command line option to force audit libraries to be run
   5   for every dynamic object loaded by an executable - provided that the loader
   6   supports this functionality.
   7
   8 * Tighten linker script grammar around file name specifiers to prevent the use
   9   of SORT_BY_ALIGNMENT and SORT_BY_INIT_PRIORITY on filenames.  These would
  10   previously be accepted but had no effect.
  11
  12 * The EXCLUDE_FILE directive can now be placed within any SORT_* directive
  13   within input section lists.
  14
  15 Changes in 2.29:
  16
  17 * Support for -z shstk in the x86 ELF linker to generate
  18   GNU_PROPERTY_X86_FEATURE_1_SHSTK in ELF GNU program properties.
  19
  20 * Add support for GNU_PROPERTY_X86_FEATURE_1_SHSTK in ELF GNU program
  21   properties in the x86 ELF linker.
  22
  23 * Add support for GNU_PROPERTY_X86_FEATURE_1_IBT in ELF GNU program
  24   properties in the x86 ELF linker.
  25
  26 * Support for -z ibtplt in the x86 ELF linker to generate IBT-enabled
  27   PLT.
  28
  29 * Support for -z ibt in the x86 ELF linker to generate IBT-enabled
  30   PLT as well as GNU_PROPERTY_X86_FEATURE_1_IBT in ELF GNU program
  31   properties.
  32
  33 * Add support for ELF SHF_GNU_MBIND and PT_GNU_MBIND_XXX.
  34
  35 * Add support for ELF GNU program properties.
  36
  37 * Add support for the Texas Instruments PRU processor.
  38
  39 * When configuring for arc*-*-linux* targets the default linker emulation will
  40   change if --with-cpu=nps400 is used at configure time.
  41
  42 * Improve assignment of LMAs to orphan sections in some edge cases where a
  43   mixture of both AT>LMA_REGION and AT(LMA) are used.
  44
  45 * Orphan sections placed after an empty section that has an AT(LMA) will now
  46   take an load memory address starting from LMA.
  47
  48 * Section groups can now be resolved (the group deleted and the group members
  49   placed like normal sections) at partial link time either using the new linker
  50   option --force-group-allocation or by placing FORCE_GROUP_ALLOCATION into the
  51   linker script.
  52
  53 Changes in 2.28:
  54
  55 * The EXCLUDE_FILE linker script construct can now be applied outside of the
  56   section list in order for the exclusions to apply over all input sections in
  57   the list.
  58
  59 * Add support for the RISC-V architecture.
  60
  61 * The command line option --no-eh-frame-hdr can now be used in ELF based
  62   linkers to disable the automatic generation of .eh_frame_hdr sections.
  63
  64 * Add --in-implib=<infile> to the ARM linker to enable specifying a set of
  65   Secure Gateway veneers that must exist in the output import library specified
  66   by --out-implib=<outfile> and the address they must have.  As such,
  67   --in-implib is only supported in combination with --cmse-implib.
  68
  69 * Extended the --out-implib=<file> option, previously restricted to x86 PE
  70   targets, to any ELF based target.  This allows the generation of an import
  71   library for an ELF executable, which can then be used by another application
  72   to link against the executable.
  73
  74 Changes in 2.27:
  75
  76 * Add a configure option --enable-relro to decide whether -z relro should
  77   be enabled in ELF linker by default.  Default to yes for all Linux
  78   targets except FRV, HPPA, IA64 and MIPS.  Note that -z relro can increase
  79   disk and memory size.
  80
  81 * Support for -z noreloc-overflow in the x86-64 ELF linker to disable
  82   relocation overflow check.
  83
  84 * Add -z common/-z nocommon options for ELF targets to control whether to
  85   convert common symbols to the STT_COMMON type during a relocatable link.
  86
  87 * Support for -z nodynamic-undefined-weak in the x86 ELF linker, which
  88   avoids dynamic relocations against undefined weak symbols in executable.
  89
  90 * The NOCROSSREFSTO command was added to the linker script language.
  91
  92 * Add --no-apply-dynamic-relocs to the AArch64 linker to do not apply link-time
  93   values for dynamic relocations.
  94
  95 Changes in 2.26:
  96
  97 * Add --fix-stm32l4xx-629360 to the ARM linker to enable a link-time
  98   workaround for a bug in the bus matrix / memory controller for some of
  99   the STM32 Cortex-M4 based products (STM32L4xx)
 100
 101 * Add a configure option --enable-compressed-debug-sections={all,ld} to
 102   decide whether DWARF debug sections should be compressed by default.
 103
 104 * Add support for the ARC EM/HS, and ARC600/700 architectures.
 105
 106 * Experimental support for linker garbage collection (--gc-sections)
 107   has been enabled for COFF and PE based targets.
 108
 109 * New command line option for ELF targets to compress DWARF debug
 110   sections, --compress-debug-sections=[none|zlib|zlib-gnu|zlib-gabi].
 111
 112 * New command line option, --orphan-handling=[place|warn|error|discard], to
 113   adjust how orphan sections are handled.  The default is 'place' which gives
 114   the current behaviour, 'warn' and 'error' issue a warning or error
 115   respectively when orphan sections are found, and 'discard' will discard all
 116   orphan sections.
 117
 118 * Add support for LLVM plugin.
 119
 120 * Add --print-memory-usage option to report memory blocks usage.
 121
 122 * Add --require-defined option, it's like --undefined except the new symbol
 123   must be defined by the end of the link.
 124
 125 Changes in 2.25:
 126
 127 * PE binaries now once again contain real timestamps by default.  To disable
 128   the inclusion of a timestamp in a PE binary, use the --no-insert-timestamp
 129   command line option.
 130
 131 * Replace support for openrisc and or32 with support for or1k.
 132
 133 * Add support for the --build-id command line option to COFF based targets.
 134
 135 * x86/x86_64 pe-coff now supports the --build-id option.
 136
 137 * Add support for the Andes NDS32.
 138
 139 Changes in 2.24:
 140
 141 * Add LOG2CEIL() builtin function to the linker script language
 142
 143 * Add support for the Texas Instruments MSP430X processor.
 144
 145 * Add support for Altera Nios II.
 146
 147 * Add support for the V850E3V5 architecture.
 148
 149 * Add support for the Imagination Technologies Meta processor.
 150
 151 * --enable-new-dtags no longer generates old dtags in addition to new dtags.
 152
 153 * Remove linker support for MIPS ECOFF targets.
 154
 155 * Add ALIGN_WITH_INPUT to the linker script language to force the alignment of
 156   an output section to use the maximum alignment of all its input sections.
 157
 158 Changes in 2.23:
 159
 160 * Enable compressed debug section feature for x86/x86_64 pe-coff.
 161
 162 * Add support for the 64-bit ARM architecture: AArch64.
 163
 164 * Added SORT_NONE to the linker script language to disable section sorting.
 165
 166 * Add a linker-provided symbol when producing ELF output, '__ehdr_start'
 167   to point to the ELF file header (and nearby program headers) in the
 168   program's memory image.
 169
 170 * Add support for S12X processor.
 171
 172 * Add support for the VLE extension to the PowerPC architecture.
 173
 174 * Add support for the Freescale XGATE architecture.
 175
 176 * Add option -f FILE on AIX (for response file).
 177
 178 * Add support for the Renesas RL78 architecture.
 179
 180 * Add support for the Adapteva EPIPHANY architecture.
 181
 182 Changes in 2.22:
 183
 184 * --copy-dt-needed-entries is no longer enabled by default.  Instead
 185   --no-copy-dt-needed-entries is the default.
 186
 187 * INPUT_SECTION_FLAGS has been added to the linker script language
 188   to allow selection of input sections by section header section flags.
 189
 190 * Add support for the Tilera TILEPro and TILE-Gx architectures.
 191
 192 * Added SORT_BY_INIT_PRIORITY to the linker script language to permit
 193   sorting sections by numerical value of the GCC init_priority attribute
 194   encoded in the section name.
 195
 196 Changes in 2.21:
 197
 198 * Linker script expression evaluation is somewhat more sane.  This may
 199   break scripts that depend on quirks of the old expression evaluation.
 200
 201 * Turn off underscoring for x86_64 PE+-COFF targets.  For old behavior the
 202   option --enable-leading-mingw64-underscores can be used on configure of
 203   bfd.
 204
 205 * Add support for the TMS320C6000 (TI C6X) processor family.
 206
 207 * --add-needed renamed to --copy-dt-needed-entries in order to avoid confusion
 208   with --as-needed option.
 209
 210 * Extend .def file syntax by '== <ID>' for imports and exports. This allows
 211   to alias the import/export table name written in PE image.
 212
 213 * Add --exclude-all-symbols option to PE based linkers.  This prevents all
 214   symbols from automatically being exported.
 215
 216 * Add support for the Renesas RX processor.
 217
 218 * Add support for alpha-vms target.
 219
 220 Changes in 2.20:
 221
 222 * GNU/Linux targets now support the STB_GNU_UNIQUE symbol binding.  This is a
 223   GNU extension to the standard set of ELF symbol bindings.  The binding will
 224   be passed on to the dynamic linker which will make sure that in the entire
 225   process there is just one symbol with the given name and type in use.
 226
 227 * PE targets now support a GNU extension to allow the alignment of common
 228   common symbols to be specified.  This support uses custom options in
 229   the .drectve section, which will be disregarded by the native tools.
 230
 231 * PE targets now add primitive support for ELF version scripts; symbols
 232   are not versioned, but the local and global symbol visibility directives
 233   are respected when filtering symbols in auto-export mode.
 234
 235 * New option --no-export-dynamic to undo the effect of the -E and
 236   --export-dynamic options.
 237
 238 * ELF: --warn-alternate-em option to warn if an object has alternate
 239   ELF machine code.
 240
 241 * New script function REGION_ALIAS to add alias names to memory regions.
 242
 243 * PE targets no longer make use of the long section names PE extension to
 244   the COFF format when generating executable images, by default.  The old
 245   (slightly non-conformant) behaviour can still be invoked by using the
 246   new '--enable-long-section-names' command-line option.  It is also enabled
 247   automatically in the presence of un-stripped debug information, as GDB
 248   needs to be able to find the debug info sections by their full names.
 249
 250 * For GNU/Linux systems the linker will now avoid processing any relocations
 251   made against symbols of the STT_GNU_IFUNC type and instead emit them into
 252   the resulting binary for processing by the loader.
 253
 254 * --as-needed now links in a dynamic library if it satisfies undefined
 255   symbols in regular objects, or in other dynamic libraries.  In the
 256   latter case the library is not linked if it is found in a DT_NEEDED
 257   entry of one of the libraries already linked.
 258
 259 * Add a new command line option, -Ttext-segment ADDR, for ELF targets
 260   to set the address of the first byte of the text segment.
 261
 262 * Add support for Sunplus score architecture.
 263
 264 * Add new option --use-nul-prefixed-import-tables to ld for PE targets to
 265   allow fallback to old import table generation with null element prefix.
 266
 267 * Windows PE systems now support a new --exclude-modules-for-implib option,
 268   allowing users to partition object files and archive members between a DLL
 269   and its associated import library as they are generated during linking.
 270
 271 * Add support for Lattice Mico32 (lm32) architecture.
 272
 273 * Add CR16 ELF --embedded-relocs (used to embedded relocations into binaries
 274   for Embedded-PIC code) option.
 275
 276 * Add to the PE/PE+ targets the support of two different kinds of
 277   pseudo-relocations.  They can be selected by the switches
 278   --enable-runtime-pseudo-reloc-v1 and --enable-runtime-pseudo-reloc-v2.
 279   For the switch --enable-runtime-pseudo-reloc it uses for 32-bit
 280   runtime pseudo relocation version one, for 64-bit the version two.
 281
 282 Changes in 2.19:
 283
 284 * Linker scripts support a new INSERT command that makes it easier to
 285   augment the default script.
 286
 287 * Linker script input section filespecs may now specify a file within an
 288   archive by writing "archive:file".
 289
 290 * The --sort-common switch now has an optional argument which specifies the
 291   direction of sorting.
 292
 293 * The M68K linker now supports multiple GOT generation schemes controlled via
 294   the --got=<type> command line option.
 295
 296 * The ARM EABI linker will now generate stubs for function calls to symbols
 297   that are too far away.  The placement of the stubs is controlled by a new
 298   linker command line option: --stub-group-size=N.
 299
 300 Changes in 2.18:
 301
 302 * Linker sources now released under version 3 of the GNU General Public
 303   License.
 304
 305 * ELF: New --build-id option to generate a unique per-binary identifier
 306   embedded in a note section.
 307
 308 * Added support for National Semicondutor CompactRISC (ie CR16) target.
 309
 310 * -l:foo now searches the library path for a filename called foo,
 311   without converting it to libfoo.a or libfoo.so.
 312
 313 * Add a new command line option '--default-script=FILE' or '-dT FILE'
 314   which specifies a replacement for the built in, default linker
 315   script.
 316
 317 * ELF: Add -Bsymbolic-functions, --dynamic-list-cpp-new, which puts C++
 318   operator new and delete on the dynamic list, and --dynamic-list-data,
 319   builtin list for --dynamic-list, which puts global data symbols on the
 320   dynamic list.
 321
 322 * Add support for x86_64 PE+ target.
 323
 324 * Add support for Score target.
 325
 326 * ELF: Add --dynamic-list option to specify a list of global symbols
 327   whose references shouldn't be bound to the definition within the
 328   shared library, or a list of symbols which should be added to the
 329   symbol table in the executable.
 330
 331 * The default output section LMA has changed for allocatable sections from
 332   being equal to VMA, to keeping the difference between LMA and VMA the same as
 333   the previous output section in the same region.  This is a more useful
 334   default when using overlays and other cases where you specify an LMA
 335   differing from the VMA for some sections.
 336
 337 * New switch: --print-gc-sections to list any sections removed by garabge
 338   collection.
 339
 340 * ARM: Added --vfp11-denorm-fix option to work around an erratum in current
 341   VFP11 coprocessors.
 342
 343 Changes in 2.17:
 344
 345 * Support for the Infineon XC16X has been added by KPIT Cummins Infosystems.
 346
 347 * Modify the Linux linker search order to better match ld.so search order.
 348   Look for DT_NEEDED libraries in paths specified by ld.so.conf before
 349   searching the default directories, rather than vice versa.
 350   Use $prefix/etc/ld.so.conf if it exists, otherwise /etc/ld.so.conf.
 351
 352 * PE-COFF: Forward exports from DLL's can now be specified in .def files
 353   passed directly to ld.
 354
 355 * Support for the Z80 processor family has been added.
 356
 357 * Add support for the "@<file>" syntax to the command line, so that extra
 358   switches can be read from <file>.
 359
 360 Changes in 2.16:
 361
 362 * Support for the R_ARM_V4BX relocation as defined in the ARM AAELF
 363   specification has been added via the --fix-v4bx command-line option.
 364
 365 * New linker script construct AS_NEEDED(), which sets the --as-needed flag
 366   for input files listed inside of it.
 367
 368 * A new command-line option, --sysroot, can be used to override the
 369   default sysroot location.  It only applies to toolchains that were
 370   configured using --with-sysroot.
 371
 372 * New linker script functions: ORIGIN() and LENGTH() which return information
 373   about a specified memory region.
 374
 375 * Port to MAXQ processor contributed by HCL Tech.
 376
 377 * Added SEGMENT_START to the linker script language to permit the user to
 378   override the base address for a segment from the command-line.
 379
 380 * ELF: --warn-shared-textrel option to warn if adding a DT_TEXTREL to a shared
 381   object.
 382
 383 * Added SORT_BY_NAME and SORT_BY_ALIGNMENT to the linker script
 384   language to permit sorting sections by section name or section
 385   maximum alignment.
 386
 387 * Added a new linker command line switch, --sort-section name|alignment,
 388   to sort sections by section name or maximum alignment.
 389
 390 * ELF: --add-needed/--no-add-needed options to control if a DT_NEEDED tag
 391   should be added when a shared library comes from DT_NEEDED tags.
 392
 393 * Support for the crx-elf target added.
 394
 395 * Support for the sh-symbianelf target added.
 396
 397 * A new linker command line switch has been added which allows the hash table
 398   size to be set to a suitable prime value near to its argument.  This switch
 399   is --hash-size=<NUMBER>.  Also if the switch --reduce-memory-overheads is
 400   used, and --hash-size has not been used, then the default value will be set
 401   to 1021.
 402
 403 * Linker map files are now generated with an O(N) algorithm for finding symbols
 404   that are defined in each section.  This uses about 40% more memory for
 405   symbols than the old O(N^2) algorithm.  You can use the new
 406   --reduce-memory-overheads option to select the old algorithm; this option
 407   might also be used in the future to select similar tradeoffs.
 408
 409 Changes in 2.15:
 410
 411 * ELF: --as-needed/--no-as-needed options to control if a DT_NEEDED tag should
 412   be added only when a shared library is referenced.
 413
 414 * PE: --large-address-aware option to indicate executables support virtual
 415   addresses greater than 2 gigabytes.
 416
 417 * DWARF 2 support for i386pe added.
 418
 419 * The linker script operator DEFINED() will now yield 1 only for a symbol that
 420   is defined before the statement where DEFINED is used.
 421
 422 * The MIPS --embedded-relocs (used to embed relocations into binaries for
 423   Embedded-PIC code) is deprecated and will be removed in a future release.
 424
 425 * cr16c support added by NSC.
 426
 427 * m32r Linux (ELF) support added by Renesas.
 428
 429 * Improved linker's handling of unresolved symbols.  The switch
 430   --unresolved-symbols=<method> has been added to tell the linker when it
 431   should report them and the switch --warn-unresolved-symbols has been added to
 432   make reports be issued as warning messages rather than errors.
 433
 434 Changes in 2.14:
 435
 436 * Added support for Xtensa architecture.
 437
 438 * Added --with-sysroot configure switch to specify a target system root, for
 439   linking against a target filesystem image.
 440
 441 * Added --accept-unknown-linker-format to restore old linker behaviour (pre
 442   2.14) of silently accepting and linking in any files in an unknown binary
 443   file format.
 444
 445 * Added --no-omagic to undo the effects of the -N option.
 446
 447 * Support for Texas Instruments TMS320C4x and TMS320C3x series of
 448   DSP's contributed by Michael Hayes and Svein E. Seldal.
 449
 450 * Added --with-lib-path configure switch to specify default value for
 451   LIB_PATH.
 452
 453 * ARM port to QNX operating system added by Graeme Peterson.
 454
 455 * IP2K support added by Denis Chertykov.
 456
 457 Changes in 2.13:
 458
 459 * Support for the Fujitsu FRV architecture added by Red Hat. Models for FR400
 460   and FR500 included.
 461
 462 Changes in version 2.13:
 463
 464 * DEC VAX ELF support, by Matt Thomas.
 465
 466 Changes in version 2.12:
 467
 468 * Support for Don Knuth's MMIX, by Hans-Peter Nilsson.
 469
 470 * Support for the OpenRISC 32-bit embedded processor by OpenCores.
 471
 472 * Support for -z nocopyreloc in the x86 ELF linker, which disables
 473   production of copy relocs.  Warning: using this option may result in
 474   non-sharable applications.
 475
 476 * Support for -z combreloc in the ELF linker, which puts dynamic
 477   relocations against the same symbol together, so that dynamic linker
 478   can use an one-entry symbol lookup cache.
 479
 480 * Support for ELF SHF_MERGE section merging, by Jakub Jelinek.
 481
 482 Changes in version 2.11:
 483
 484 * Support for AMD x86-64 architecture, by Jan Hubicka, SuSE Labs.
 485
 486 * Support added for eliminating duplicate DWARF2 debug information by
 487   having the compiler generate the information in sections called
 488   .gnu.linkonce.wi.XXXX where XXXX is a checksum for the contents.  The
 489   linker then merges these sections together into the normal .debug_info
 490   section.
 491
 492 * The native ELF linker now searches the directories in DT_RUNPATH or
 493   DT_RPATH of a shared library for shared libraries needed by it.
 494
 495 * TI C54x support, by Timothy Wall.
 496
 497 * Added command line switch --section-start to set the start address of any
 498   specified section.
 499
 500 * Added ability to emit full relocation information in linked executables,
 501   enabled by --emit-relocs.  Some post-linkage optimization tools need
 502   this information in order to be able to correctly identify and perform
 503   symbol relative addressing in the event of changes in section contents
 504   (instructions being added or deleted, extending data sections, etc.)
 505
 506 * Support for i860, by Jason Eckhardt (preliminary, alpha quality).
 507
 508 * Support for CRIS (Axis Communications ETRAX series).
 509
 510 * Support for PDP-11 and 2.11BSD a.out format, by Lars Brinkhoff.
 511
 512 Changes in version 2.10:
 513
 514 * Added AT> to the linker script language to allow load-time allocation of
 515   sections into regions.
 516
 517 * Added garbage collection of unused sections, enabled by --gc-sections.
 518   It does require a bit of backend support; currently implemented are
 519   arm-elf, avr-elf, d10v-elf, fr30-elf, i386-elf, m32r-elf, m68k-elf,
 520   mcore-elf, mips-elf, mn10300-elf, ppc-elf, sh-elf, sparc-elf, and v850-elf.
 521   Others will ignore the option.
 522
 523 * Added SORT to the linker script language to permit sorting sections by file
 524   name or section name.
 525
 526 * Added EXTERN to the linker script language as an equivalent to the -u
 527   command-line option.
 528
 529 * Added ASSERT to the linker script language.
 530
 531 * Added EXCLUDE_FILE to the linker script language for further control over
 532   wildcard file names.
 533
 534 * Added -O option to optimize linker output (as of this writing, this only
 535   affects ELF shared library generation).
 536
 537 * The -e option now accepts a number as well as a symbol name.
 538
 539 * Added --no-undefined option to disallow undefined symbols when creating a
 540   shared library.
 541
 542 * The linker now issues a warning, not an error, for an undefined symbol when
 543   using -Bsymbolic; use the new --no-undefined option to get the old
 544   behaviour.
 545
 546 * Added --demangle and --no-demangle options.
 547
 548 Changes in version 2.9:
 549
 550 * Added SQUAD to the linker script language.
 551
 552 * New option --no-warn-mismatch.
 553
 554 * The MEMORY command now parses the attributes to determine where sections that
 555   are not placed in a specific memory region are placed.
 556
 557 Changes in version 2.8:
 558
 559 * Linker scripts may now contain shell wildcard characters for file and section
 560   names.
 561
 562 * The linker now supports symbol versions in ELF.
 563
 564 * The NOCROSSREFS command was added to the linker script language.
 565
 566 * The LOADADDR expression was added to the linker script language.
 567
 568 * MAX and MIN functions were added to the linker script language.
 569
 570 * The OVERLAY construct was added to the linker script language.
 571
 572 * New option --warn-section-align to warn when the address of an output section
 573   changes due to alignment of an input section.
 574
 575 * New options --filter/-F and --auxiliary/-f.
 576
 577 Changes in version 2.7:
 578
 579 * New option --cref to print out a cross reference table.
 580
 581 * New option --wrap SYMBOL.
 582
 583 * New option --no-whole-archive, to turn off the effect of --whole-archive.
 584
 585 * Input sections assigned to the output section /DISCARD/ in the linker script
 586   are not included in the output file.
 587
 588 * The SunOS and ELF linkers now merge stabs debugging information which uses
 589   the N_BINCL and N_EINCL stab types.  This reduces the amount of debugging
 590   information generated.
 591
 592 Changes in version 2.6:
 593
 594 * When an ELF section name is representable as a C identifier (this is not true
 595 of most ELF section names), the linker will automatically define symbols
 596 __start_SECNAME and __stop_SECNAME, where SECNAME is the section name, at the
 597 beginning and the end of the section.  This is used by glibc.
 598
 599   Addendum: Current versions of the linker (at least for version 2.18 onwards
 600 and possibly much earlier as well) place two restrictions on this feature:  The
 601 symbols are only implemented for orphaned sections, not for explicitly placed
 602 sections and they are PROVIDEd rather than being defined.
 603
 604 * When an ELF section named .gnu.warning is encountered in an input file, the
 605 contents of the section are displayed as an error message, and the section is
 606 not copied into the output file.  This is used by glibc.
 607
 608 * When an ELF section named .gnu.warning.SYMBOL is encountered in an input
 609 file, and the symbol SYMBOL is referenced by some object file, the contents of
 610 the section are displayed as an error message.  The section is not copied into
 611 the output file, unless doing a relocatable or shared link.  This is used by
 612 glibc.
 613
 614 * New options -split-by-reloc and -split-by-file.
 615
 616 * The linker now supports linking PIC compiled code on SPARC SunOS.  It can
 617 also create SPARC SunOS shared libraries, and, like the native SunOS linker,
 618 will do so whenever there is an undefined symbol in the link and neither the -e
 619 nor the -r option was used.
 620
 621 * The -rpath option may be used on SunOS to set the list of directories to be
 622 searched at run time.  This overrides the default of building the list from the
 623 -L options.
 624
 625 * The COFF linker now combines debugging information for structs, unions, and
 626 enums, so that even if the same type is defined in multiple input files it will
 627 only be defined once in the output file.  The --traditional-format switch will
 628 prevent this optimization.
 629
 630 Changes in version 2.5:
 631
 632 * The linker now supports linking against SunOS shared libraries.  It still can
 633 not link SunOS PIC (Position Independent Code) files, so it can not be used to
 634 generate shared libraries.
 635
 636 * The linker now supports linking against ELF shared libraries for the i386
 637 (UnixWare) and SPARC (Solaris).  It can also link ELF PIC files, and can be
 638 used to generate shared libraries.  Shared library generation is not well
 639 tested; please report any problems encountered.  The linker is now enabled for
 640 Solaris again.
 641
 642 * Eric Youngdale has contributed Linux support code, including linking against
 643 Linux a.out shared libraries.  The linker produces Linux QMAGIC binaries.
 644
 645 * The ELF backend has been converted to the new linker code.  To use the new
 646 ELF linker, each particular target requires a relocation function.  So far,
 647 this function has been written for i386 (UnixWare), SPARC (Solaris) MIPS (Irix
 648 5), and HPPA ELF targets.
 649
 650 * The -( (--start-group) and -) (--end-group) options have been added to
 651 support searching a group of archives as though they were a single archive.
 652 This can also be used in a linker script, as GROUP ( files ).
 653
 654 * When a file is named on the command line, and the linker does not recognize
 655 it as an object file, the linker will now treat the file as a linker script
 656 file.  A linker script named in this way augments, but does not replace, the
 657 default linker script.
 658
 659 * The -warn-once option was added.  It causes the linker to only warn once per
 660 undefined symbol, rather than once per reference.
 661
 662 * The COFF backend has been converted to the new linker code.  As with ELF, to
 663 use the new linker, each particular target requires a relocation function.  So
 664 far, this function has been written for the i386, m68k, a29k and SH targets.
 665
 666 * The -V flag was made a synonym for -v, for SVR4 compatibility.  The old -V
 667 behaviour is available via --verbose.
 668
 669 Changes in version 2.4:
 670
 671 * New linker code, by Steve Chamberlain and Ian Taylor.  For a.out and ecoff
 672   formats (so far), this should result in considerable savings in time
 673   and memory used while linking; slightly poorer performance than
 674   before for formats not converted yet.
 675
 676 * Command-line parsing is no longer done with flex.  This means
 677   oddball characters in filenames won't get treated as argument
 678   separators.
 679
 680 * HP-PA ELF support, by Jeff Law.  (No SOM support yet.)
 681
 682 * Mach i386 support, by David Mackenzie.
 683
 684 * Irix 4 shared libraries are now supported (Irix 5 uses ELF, and ELF shared
 685   libraries are not yet supported).
 686
 687 * COFF shared libraries (as on SCO) should work as well.
 688
 689 * The linker is disabled for Solaris.  (Actually, it was in 2.3 also, I just
 690   forgot to note it.)  Some of their C library routines don't work when
 691   statically linked, and the GNU linker doesn't support dynamic linking yet.
 692
 693 Changes in version 2.3:
 694
 695 * Weak symbols are now supported.
 696
 697 * ELF support has been added.  The linker has been bootstrapped on
 698   UnixWare and Solaris.
 699
 700 * Alpha OSF/1 support has been added (non dynamic linking only).
 701
 702 Changes in version 2.2:
 703
 704 * The `bfd' library has been updated to reduce a.out-format string
 705   table size.  The effect of this is that files linked from many input
 706   files with duplicate symbols (`-g' debugging records, or identical
 707   static symbols) should be much smaller.
 708
 709 Changes in version 2.1:
 710
 711 * The ld -ySYMBOL flag (to trace references to SYMBOL) is now implemented.
 712
 713 * There is now support for writing ECOFF files, so ld and the
 714   other utilities should work on Risc/Ultrix and Irix.
 715
 716 \f
 717 Copyright (C) 2012-2018 Free Software Foundation, Inc.
 718
 719 Copying and distribution of this file, with or without modification,
 720 are permitted in any medium without royalty provided the copyright
 721 notice and this notice are preserved.
 722
 723 Local variables:
 724 fill-column: 79
 725 End: