ld/NEWS

   1 -*- text -*-
   2
   3 * Add a configure option --enable-separate-code to decide whether
   4   -z separate-code should be enabled in ELF linker by default.  Default
   5   to yes for Linux/x86 targets.  Note that -z separate-code can increase
   6   disk and memory size.
   7
   8 Changes in 2.30:
   9
  10 * Add -z separate-code to generate separate code PT_LOAD segment.
  11
  12 * Add "-z undefs" command line option as the inverse of the "-z defs" option.
  13
  14 * Add -z globalaudit command line option to force audit libraries to be run
  15   for every dynamic object loaded by an executable - provided that the loader
  16   supports this functionality.
  17
  18 * Tighten linker script grammar around file name specifiers to prevent the use
  19   of SORT_BY_ALIGNMENT and SORT_BY_INIT_PRIORITY on filenames.  These would
  20   previously be accepted but had no effect.
  21
  22 * The EXCLUDE_FILE directive can now be placed within any SORT_* directive
  23   within input section lists.
  24
  25 Changes in 2.29:
  26
  27 * Support for -z shstk in the x86 ELF linker to generate
  28   GNU_PROPERTY_X86_FEATURE_1_SHSTK in ELF GNU program properties.
  29
  30 * Add support for GNU_PROPERTY_X86_FEATURE_1_SHSTK in ELF GNU program
  31   properties in the x86 ELF linker.
  32
  33 * Add support for GNU_PROPERTY_X86_FEATURE_1_IBT in ELF GNU program
  34   properties in the x86 ELF linker.
  35
  36 * Support for -z ibtplt in the x86 ELF linker to generate IBT-enabled
  37   PLT.
  38
  39 * Support for -z ibt in the x86 ELF linker to generate IBT-enabled
  40   PLT as well as GNU_PROPERTY_X86_FEATURE_1_IBT in ELF GNU program
  41   properties.
  42
  43 * Add support for ELF SHF_GNU_MBIND and PT_GNU_MBIND_XXX.
  44
  45 * Add support for ELF GNU program properties.
  46
  47 * Add support for the Texas Instruments PRU processor.
  48
  49 * When configuring for arc*-*-linux* targets the default linker emulation will
  50   change if --with-cpu=nps400 is used at configure time.
  51
  52 * Improve assignment of LMAs to orphan sections in some edge cases where a
  53   mixture of both AT>LMA_REGION and AT(LMA) are used.
  54
  55 * Orphan sections placed after an empty section that has an AT(LMA) will now
  56   take an load memory address starting from LMA.
  57
  58 * Section groups can now be resolved (the group deleted and the group members
  59   placed like normal sections) at partial link time either using the new linker
  60   option --force-group-allocation or by placing FORCE_GROUP_ALLOCATION into the
  61   linker script.
  62
  63 Changes in 2.28:
  64
  65 * The EXCLUDE_FILE linker script construct can now be applied outside of the
  66   section list in order for the exclusions to apply over all input sections in
  67   the list.
  68
  69 * Add support for the RISC-V architecture.
  70
  71 * The command line option --no-eh-frame-hdr can now be used in ELF based
  72   linkers to disable the automatic generation of .eh_frame_hdr sections.
  73
  74 * Add --in-implib=<infile> to the ARM linker to enable specifying a set of
  75   Secure Gateway veneers that must exist in the output import library specified
  76   by --out-implib=<outfile> and the address they must have.  As such,
  77   --in-implib is only supported in combination with --cmse-implib.
  78
  79 * Extended the --out-implib=<file> option, previously restricted to x86 PE
  80   targets, to any ELF based target.  This allows the generation of an import
  81   library for an ELF executable, which can then be used by another application
  82   to link against the executable.
  83
  84 Changes in 2.27:
  85
  86 * Add a configure option --enable-relro to decide whether -z relro should
  87   be enabled in ELF linker by default.  Default to yes for all Linux
  88   targets except FRV, HPPA, IA64 and MIPS.  Note that -z relro can increase
  89   disk and memory size.
  90
  91 * Support for -z noreloc-overflow in the x86-64 ELF linker to disable
  92   relocation overflow check.
  93
  94 * Add -z common/-z nocommon options for ELF targets to control whether to
  95   convert common symbols to the STT_COMMON type during a relocatable link.
  96
  97 * Support for -z nodynamic-undefined-weak in the x86 ELF linker, which
  98   avoids dynamic relocations against undefined weak symbols in executable.
  99
 100 * The NOCROSSREFSTO command was added to the linker script language.
 101
 102 * Add --no-apply-dynamic-relocs to the AArch64 linker to do not apply link-time
 103   values for dynamic relocations.
 104
 105 Changes in 2.26:
 106
 107 * Add --fix-stm32l4xx-629360 to the ARM linker to enable a link-time
 108   workaround for a bug in the bus matrix / memory controller for some of
 109   the STM32 Cortex-M4 based products (STM32L4xx)
 110
 111 * Add a configure option --enable-compressed-debug-sections={all,ld} to
 112   decide whether DWARF debug sections should be compressed by default.
 113
 114 * Add support for the ARC EM/HS, and ARC600/700 architectures.
 115
 116 * Experimental support for linker garbage collection (--gc-sections)
 117   has been enabled for COFF and PE based targets.
 118
 119 * New command line option for ELF targets to compress DWARF debug
 120   sections, --compress-debug-sections=[none|zlib|zlib-gnu|zlib-gabi].
 121
 122 * New command line option, --orphan-handling=[place|warn|error|discard], to
 123   adjust how orphan sections are handled.  The default is 'place' which gives
 124   the current behaviour, 'warn' and 'error' issue a warning or error
 125   respectively when orphan sections are found, and 'discard' will discard all
 126   orphan sections.
 127
 128 * Add support for LLVM plugin.
 129
 130 * Add --print-memory-usage option to report memory blocks usage.
 131
 132 * Add --require-defined option, it's like --undefined except the new symbol
 133   must be defined by the end of the link.
 134
 135 Changes in 2.25:
 136
 137 * PE binaries now once again contain real timestamps by default.  To disable
 138   the inclusion of a timestamp in a PE binary, use the --no-insert-timestamp
 139   command line option.
 140
 141 * Replace support for openrisc and or32 with support for or1k.
 142
 143 * Add support for the --build-id command line option to COFF based targets.
 144
 145 * x86/x86_64 pe-coff now supports the --build-id option.
 146
 147 * Add support for the Andes NDS32.
 148
 149 Changes in 2.24:
 150
 151 * Add LOG2CEIL() builtin function to the linker script language
 152
 153 * Add support for the Texas Instruments MSP430X processor.
 154
 155 * Add support for Altera Nios II.
 156
 157 * Add support for the V850E3V5 architecture.
 158
 159 * Add support for the Imagination Technologies Meta processor.
 160
 161 * --enable-new-dtags no longer generates old dtags in addition to new dtags.
 162
 163 * Remove linker support for MIPS ECOFF targets.
 164
 165 * Add ALIGN_WITH_INPUT to the linker script language to force the alignment of
 166   an output section to use the maximum alignment of all its input sections.
 167
 168 Changes in 2.23:
 169
 170 * Enable compressed debug section feature for x86/x86_64 pe-coff.
 171
 172 * Add support for the 64-bit ARM architecture: AArch64.
 173
 174 * Added SORT_NONE to the linker script language to disable section sorting.
 175
 176 * Add a linker-provided symbol when producing ELF output, '__ehdr_start'
 177   to point to the ELF file header (and nearby program headers) in the
 178   program's memory image.
 179
 180 * Add support for S12X processor.
 181
 182 * Add support for the VLE extension to the PowerPC architecture.
 183
 184 * Add support for the Freescale XGATE architecture.
 185
 186 * Add option -f FILE on AIX (for response file).
 187
 188 * Add support for the Renesas RL78 architecture.
 189
 190 * Add support for the Adapteva EPIPHANY architecture.
 191
 192 Changes in 2.22:
 193
 194 * --copy-dt-needed-entries is no longer enabled by default.  Instead
 195   --no-copy-dt-needed-entries is the default.
 196
 197 * INPUT_SECTION_FLAGS has been added to the linker script language
 198   to allow selection of input sections by section header section flags.
 199
 200 * Add support for the Tilera TILEPro and TILE-Gx architectures.
 201
 202 * Added SORT_BY_INIT_PRIORITY to the linker script language to permit
 203   sorting sections by numerical value of the GCC init_priority attribute
 204   encoded in the section name.
 205
 206 Changes in 2.21:
 207
 208 * Linker script expression evaluation is somewhat more sane.  This may
 209   break scripts that depend on quirks of the old expression evaluation.
 210
 211 * Turn off underscoring for x86_64 PE+-COFF targets.  For old behavior the
 212   option --enable-leading-mingw64-underscores can be used on configure of
 213   bfd.
 214
 215 * Add support for the TMS320C6000 (TI C6X) processor family.
 216
 217 * --add-needed renamed to --copy-dt-needed-entries in order to avoid confusion
 218   with --as-needed option.
 219
 220 * Extend .def file syntax by '== <ID>' for imports and exports. This allows
 221   to alias the import/export table name written in PE image.
 222
 223 * Add --exclude-all-symbols option to PE based linkers.  This prevents all
 224   symbols from automatically being exported.
 225
 226 * Add support for the Renesas RX processor.
 227
 228 * Add support for alpha-vms target.
 229
 230 Changes in 2.20:
 231
 232 * GNU/Linux targets now support the STB_GNU_UNIQUE symbol binding.  This is a
 233   GNU extension to the standard set of ELF symbol bindings.  The binding will
 234   be passed on to the dynamic linker which will make sure that in the entire
 235   process there is just one symbol with the given name and type in use.
 236
 237 * PE targets now support a GNU extension to allow the alignment of common
 238   common symbols to be specified.  This support uses custom options in
 239   the .drectve section, which will be disregarded by the native tools.
 240
 241 * PE targets now add primitive support for ELF version scripts; symbols
 242   are not versioned, but the local and global symbol visibility directives
 243   are respected when filtering symbols in auto-export mode.
 244
 245 * New option --no-export-dynamic to undo the effect of the -E and
 246   --export-dynamic options.
 247
 248 * ELF: --warn-alternate-em option to warn if an object has alternate
 249   ELF machine code.
 250
 251 * New script function REGION_ALIAS to add alias names to memory regions.
 252
 253 * PE targets no longer make use of the long section names PE extension to
 254   the COFF format when generating executable images, by default.  The old
 255   (slightly non-conformant) behaviour can still be invoked by using the
 256   new '--enable-long-section-names' command-line option.  It is also enabled
 257   automatically in the presence of un-stripped debug information, as GDB
 258   needs to be able to find the debug info sections by their full names.
 259
 260 * For GNU/Linux systems the linker will now avoid processing any relocations
 261   made against symbols of the STT_GNU_IFUNC type and instead emit them into
 262   the resulting binary for processing by the loader.
 263
 264 * --as-needed now links in a dynamic library if it satisfies undefined
 265   symbols in regular objects, or in other dynamic libraries.  In the
 266   latter case the library is not linked if it is found in a DT_NEEDED
 267   entry of one of the libraries already linked.
 268
 269 * Add a new command line option, -Ttext-segment ADDR, for ELF targets
 270   to set the address of the first byte of the text segment.
 271
 272 * Add support for Sunplus score architecture.
 273
 274 * Add new option --use-nul-prefixed-import-tables to ld for PE targets to
 275   allow fallback to old import table generation with null element prefix.
 276
 277 * Windows PE systems now support a new --exclude-modules-for-implib option,
 278   allowing users to partition object files and archive members between a DLL
 279   and its associated import library as they are generated during linking.
 280
 281 * Add support for Lattice Mico32 (lm32) architecture.
 282
 283 * Add CR16 ELF --embedded-relocs (used to embedded relocations into binaries
 284   for Embedded-PIC code) option.
 285
 286 * Add to the PE/PE+ targets the support of two different kinds of
 287   pseudo-relocations.  They can be selected by the switches
 288   --enable-runtime-pseudo-reloc-v1 and --enable-runtime-pseudo-reloc-v2.
 289   For the switch --enable-runtime-pseudo-reloc it uses for 32-bit
 290   runtime pseudo relocation version one, for 64-bit the version two.
 291
 292 Changes in 2.19:
 293
 294 * Linker scripts support a new INSERT command that makes it easier to
 295   augment the default script.
 296
 297 * Linker script input section filespecs may now specify a file within an
 298   archive by writing "archive:file".
 299
 300 * The --sort-common switch now has an optional argument which specifies the
 301   direction of sorting.
 302
 303 * The M68K linker now supports multiple GOT generation schemes controlled via
 304   the --got=<type> command line option.
 305
 306 * The ARM EABI linker will now generate stubs for function calls to symbols
 307   that are too far away.  The placement of the stubs is controlled by a new
 308   linker command line option: --stub-group-size=N.
 309
 310 Changes in 2.18:
 311
 312 * Linker sources now released under version 3 of the GNU General Public
 313   License.
 314
 315 * ELF: New --build-id option to generate a unique per-binary identifier
 316   embedded in a note section.
 317
 318 * Added support for National Semicondutor CompactRISC (ie CR16) target.
 319
 320 * -l:foo now searches the library path for a filename called foo,
 321   without converting it to libfoo.a or libfoo.so.
 322
 323 * Add a new command line option '--default-script=FILE' or '-dT FILE'
 324   which specifies a replacement for the built in, default linker
 325   script.
 326
 327 * ELF: Add -Bsymbolic-functions, --dynamic-list-cpp-new, which puts C++
 328   operator new and delete on the dynamic list, and --dynamic-list-data,
 329   builtin list for --dynamic-list, which puts global data symbols on the
 330   dynamic list.
 331
 332 * Add support for x86_64 PE+ target.
 333
 334 * Add support for Score target.
 335
 336 * ELF: Add --dynamic-list option to specify a list of global symbols
 337   whose references shouldn't be bound to the definition within the
 338   shared library, or a list of symbols which should be added to the
 339   symbol table in the executable.
 340
 341 * The default output section LMA has changed for allocatable sections from
 342   being equal to VMA, to keeping the difference between LMA and VMA the same as
 343   the previous output section in the same region.  This is a more useful
 344   default when using overlays and other cases where you specify an LMA
 345   differing from the VMA for some sections.
 346
 347 * New switch: --print-gc-sections to list any sections removed by garabge
 348   collection.
 349
 350 * ARM: Added --vfp11-denorm-fix option to work around an erratum in current
 351   VFP11 coprocessors.
 352
 353 Changes in 2.17:
 354
 355 * Support for the Infineon XC16X has been added by KPIT Cummins Infosystems.
 356
 357 * Modify the Linux linker search order to better match ld.so search order.
 358   Look for DT_NEEDED libraries in paths specified by ld.so.conf before
 359   searching the default directories, rather than vice versa.
 360   Use $prefix/etc/ld.so.conf if it exists, otherwise /etc/ld.so.conf.
 361
 362 * PE-COFF: Forward exports from DLL's can now be specified in .def files
 363   passed directly to ld.
 364
 365 * Support for the Z80 processor family has been added.
 366
 367 * Add support for the "@<file>" syntax to the command line, so that extra
 368   switches can be read from <file>.
 369
 370 Changes in 2.16:
 371
 372 * Support for the R_ARM_V4BX relocation as defined in the ARM AAELF
 373   specification has been added via the --fix-v4bx command-line option.
 374
 375 * New linker script construct AS_NEEDED(), which sets the --as-needed flag
 376   for input files listed inside of it.
 377
 378 * A new command-line option, --sysroot, can be used to override the
 379   default sysroot location.  It only applies to toolchains that were
 380   configured using --with-sysroot.
 381
 382 * New linker script functions: ORIGIN() and LENGTH() which return information
 383   about a specified memory region.
 384
 385 * Port to MAXQ processor contributed by HCL Tech.
 386
 387 * Added SEGMENT_START to the linker script language to permit the user to
 388   override the base address for a segment from the command-line.
 389
 390 * ELF: --warn-shared-textrel option to warn if adding a DT_TEXTREL to a shared
 391   object.
 392
 393 * Added SORT_BY_NAME and SORT_BY_ALIGNMENT to the linker script
 394   language to permit sorting sections by section name or section
 395   maximum alignment.
 396
 397 * Added a new linker command line switch, --sort-section name|alignment,
 398   to sort sections by section name or maximum alignment.
 399
 400 * ELF: --add-needed/--no-add-needed options to control if a DT_NEEDED tag
 401   should be added when a shared library comes from DT_NEEDED tags.
 402
 403 * Support for the crx-elf target added.
 404
 405 * Support for the sh-symbianelf target added.
 406
 407 * A new linker command line switch has been added which allows the hash table
 408   size to be set to a suitable prime value near to its argument.  This switch
 409   is --hash-size=<NUMBER>.  Also if the switch --reduce-memory-overheads is
 410   used, and --hash-size has not been used, then the default value will be set
 411   to 1021.
 412
 413 * Linker map files are now generated with an O(N) algorithm for finding symbols
 414   that are defined in each section.  This uses about 40% more memory for
 415   symbols than the old O(N^2) algorithm.  You can use the new
 416   --reduce-memory-overheads option to select the old algorithm; this option
 417   might also be used in the future to select similar tradeoffs.
 418
 419 Changes in 2.15:
 420
 421 * ELF: --as-needed/--no-as-needed options to control if a DT_NEEDED tag should
 422   be added only when a shared library is referenced.
 423
 424 * PE: --large-address-aware option to indicate executables support virtual
 425   addresses greater than 2 gigabytes.
 426
 427 * DWARF 2 support for i386pe added.
 428
 429 * The linker script operator DEFINED() will now yield 1 only for a symbol that
 430   is defined before the statement where DEFINED is used.
 431
 432 * The MIPS --embedded-relocs (used to embed relocations into binaries for
 433   Embedded-PIC code) is deprecated and will be removed in a future release.
 434
 435 * cr16c support added by NSC.
 436
 437 * m32r Linux (ELF) support added by Renesas.
 438
 439 * Improved linker's handling of unresolved symbols.  The switch
 440   --unresolved-symbols=<method> has been added to tell the linker when it
 441   should report them and the switch --warn-unresolved-symbols has been added to
 442   make reports be issued as warning messages rather than errors.
 443
 444 Changes in 2.14:
 445
 446 * Added support for Xtensa architecture.
 447
 448 * Added --with-sysroot configure switch to specify a target system root, for
 449   linking against a target filesystem image.
 450
 451 * Added --accept-unknown-linker-format to restore old linker behaviour (pre
 452   2.14) of silently accepting and linking in any files in an unknown binary
 453   file format.
 454
 455 * Added --no-omagic to undo the effects of the -N option.
 456
 457 * Support for Texas Instruments TMS320C4x and TMS320C3x series of
 458   DSP's contributed by Michael Hayes and Svein E. Seldal.
 459
 460 * Added --with-lib-path configure switch to specify default value for
 461   LIB_PATH.
 462
 463 * ARM port to QNX operating system added by Graeme Peterson.
 464
 465 * IP2K support added by Denis Chertykov.
 466
 467 Changes in 2.13:
 468
 469 * Support for the Fujitsu FRV architecture added by Red Hat. Models for FR400
 470   and FR500 included.
 471
 472 Changes in version 2.13:
 473
 474 * DEC VAX ELF support, by Matt Thomas.
 475
 476 Changes in version 2.12:
 477
 478 * Support for Don Knuth's MMIX, by Hans-Peter Nilsson.
 479
 480 * Support for the OpenRISC 32-bit embedded processor by OpenCores.
 481
 482 * Support for -z nocopyreloc in the x86 ELF linker, which disables
 483   production of copy relocs.  Warning: using this option may result in
 484   non-sharable applications.
 485
 486 * Support for -z combreloc in the ELF linker, which puts dynamic
 487   relocations against the same symbol together, so that dynamic linker
 488   can use an one-entry symbol lookup cache.
 489
 490 * Support for ELF SHF_MERGE section merging, by Jakub Jelinek.
 491
 492 Changes in version 2.11:
 493
 494 * Support for AMD x86-64 architecture, by Jan Hubicka, SuSE Labs.
 495
 496 * Support added for eliminating duplicate DWARF2 debug information by
 497   having the compiler generate the information in sections called
 498   .gnu.linkonce.wi.XXXX where XXXX is a checksum for the contents.  The
 499   linker then merges these sections together into the normal .debug_info
 500   section.
 501
 502 * The native ELF linker now searches the directories in DT_RUNPATH or
 503   DT_RPATH of a shared library for shared libraries needed by it.
 504
 505 * TI C54x support, by Timothy Wall.
 506
 507 * Added command line switch --section-start to set the start address of any
 508   specified section.
 509
 510 * Added ability to emit full relocation information in linked executables,
 511   enabled by --emit-relocs.  Some post-linkage optimization tools need
 512   this information in order to be able to correctly identify and perform
 513   symbol relative addressing in the event of changes in section contents
 514   (instructions being added or deleted, extending data sections, etc.)
 515
 516 * Support for i860, by Jason Eckhardt (preliminary, alpha quality).
 517
 518 * Support for CRIS (Axis Communications ETRAX series).
 519
 520 * Support for PDP-11 and 2.11BSD a.out format, by Lars Brinkhoff.
 521
 522 Changes in version 2.10:
 523
 524 * Added AT> to the linker script language to allow load-time allocation of
 525   sections into regions.
 526
 527 * Added garbage collection of unused sections, enabled by --gc-sections.
 528   It does require a bit of backend support; currently implemented are
 529   arm-elf, avr-elf, d10v-elf, fr30-elf, i386-elf, m32r-elf, m68k-elf,
 530   mcore-elf, mips-elf, mn10300-elf, ppc-elf, sh-elf, sparc-elf, and v850-elf.
 531   Others will ignore the option.
 532
 533 * Added SORT to the linker script language to permit sorting sections by file
 534   name or section name.
 535
 536 * Added EXTERN to the linker script language as an equivalent to the -u
 537   command-line option.
 538
 539 * Added ASSERT to the linker script language.
 540
 541 * Added EXCLUDE_FILE to the linker script language for further control over
 542   wildcard file names.
 543
 544 * Added -O option to optimize linker output (as of this writing, this only
 545   affects ELF shared library generation).
 546
 547 * The -e option now accepts a number as well as a symbol name.
 548
 549 * Added --no-undefined option to disallow undefined symbols when creating a
 550   shared library.
 551
 552 * The linker now issues a warning, not an error, for an undefined symbol when
 553   using -Bsymbolic; use the new --no-undefined option to get the old
 554   behaviour.
 555
 556 * Added --demangle and --no-demangle options.
 557
 558 Changes in version 2.9:
 559
 560 * Added SQUAD to the linker script language.
 561
 562 * New option --no-warn-mismatch.
 563
 564 * The MEMORY command now parses the attributes to determine where sections that
 565   are not placed in a specific memory region are placed.
 566
 567 Changes in version 2.8:
 568
 569 * Linker scripts may now contain shell wildcard characters for file and section
 570   names.
 571
 572 * The linker now supports symbol versions in ELF.
 573
 574 * The NOCROSSREFS command was added to the linker script language.
 575
 576 * The LOADADDR expression was added to the linker script language.
 577
 578 * MAX and MIN functions were added to the linker script language.
 579
 580 * The OVERLAY construct was added to the linker script language.
 581
 582 * New option --warn-section-align to warn when the address of an output section
 583   changes due to alignment of an input section.
 584
 585 * New options --filter/-F and --auxiliary/-f.
 586
 587 Changes in version 2.7:
 588
 589 * New option --cref to print out a cross reference table.
 590
 591 * New option --wrap SYMBOL.
 592
 593 * New option --no-whole-archive, to turn off the effect of --whole-archive.
 594
 595 * Input sections assigned to the output section /DISCARD/ in the linker script
 596   are not included in the output file.
 597
 598 * The SunOS and ELF linkers now merge stabs debugging information which uses
 599   the N_BINCL and N_EINCL stab types.  This reduces the amount of debugging
 600   information generated.
 601
 602 Changes in version 2.6:
 603
 604 * When an ELF section name is representable as a C identifier (this is not true
 605 of most ELF section names), the linker will automatically define symbols
 606 __start_SECNAME and __stop_SECNAME, where SECNAME is the section name, at the
 607 beginning and the end of the section.  This is used by glibc.
 608
 609   Addendum: Current versions of the linker (at least for version 2.18 onwards
 610 and possibly much earlier as well) place two restrictions on this feature:  The
 611 symbols are only implemented for orphaned sections, not for explicitly placed
 612 sections and they are PROVIDEd rather than being defined.
 613
 614 * When an ELF section named .gnu.warning is encountered in an input file, the
 615 contents of the section are displayed as an error message, and the section is
 616 not copied into the output file.  This is used by glibc.
 617
 618 * When an ELF section named .gnu.warning.SYMBOL is encountered in an input
 619 file, and the symbol SYMBOL is referenced by some object file, the contents of
 620 the section are displayed as an error message.  The section is not copied into
 621 the output file, unless doing a relocatable or shared link.  This is used by
 622 glibc.
 623
 624 * New options -split-by-reloc and -split-by-file.
 625
 626 * The linker now supports linking PIC compiled code on SPARC SunOS.  It can
 627 also create SPARC SunOS shared libraries, and, like the native SunOS linker,
 628 will do so whenever there is an undefined symbol in the link and neither the -e
 629 nor the -r option was used.
 630
 631 * The -rpath option may be used on SunOS to set the list of directories to be
 632 searched at run time.  This overrides the default of building the list from the
 633 -L options.
 634
 635 * The COFF linker now combines debugging information for structs, unions, and
 636 enums, so that even if the same type is defined in multiple input files it will
 637 only be defined once in the output file.  The --traditional-format switch will
 638 prevent this optimization.
 639
 640 Changes in version 2.5:
 641
 642 * The linker now supports linking against SunOS shared libraries.  It still can
 643 not link SunOS PIC (Position Independent Code) files, so it can not be used to
 644 generate shared libraries.
 645
 646 * The linker now supports linking against ELF shared libraries for the i386
 647 (UnixWare) and SPARC (Solaris).  It can also link ELF PIC files, and can be
 648 used to generate shared libraries.  Shared library generation is not well
 649 tested; please report any problems encountered.  The linker is now enabled for
 650 Solaris again.
 651
 652 * Eric Youngdale has contributed Linux support code, including linking against
 653 Linux a.out shared libraries.  The linker produces Linux QMAGIC binaries.
 654
 655 * The ELF backend has been converted to the new linker code.  To use the new
 656 ELF linker, each particular target requires a relocation function.  So far,
 657 this function has been written for i386 (UnixWare), SPARC (Solaris) MIPS (Irix
 658 5), and HPPA ELF targets.
 659
 660 * The -( (--start-group) and -) (--end-group) options have been added to
 661 support searching a group of archives as though they were a single archive.
 662 This can also be used in a linker script, as GROUP ( files ).
 663
 664 * When a file is named on the command line, and the linker does not recognize
 665 it as an object file, the linker will now treat the file as a linker script
 666 file.  A linker script named in this way augments, but does not replace, the
 667 default linker script.
 668
 669 * The -warn-once option was added.  It causes the linker to only warn once per
 670 undefined symbol, rather than once per reference.
 671
 672 * The COFF backend has been converted to the new linker code.  As with ELF, to
 673 use the new linker, each particular target requires a relocation function.  So
 674 far, this function has been written for the i386, m68k, a29k and SH targets.
 675
 676 * The -V flag was made a synonym for -v, for SVR4 compatibility.  The old -V
 677 behaviour is available via --verbose.
 678
 679 Changes in version 2.4:
 680
 681 * New linker code, by Steve Chamberlain and Ian Taylor.  For a.out and ecoff
 682   formats (so far), this should result in considerable savings in time
 683   and memory used while linking; slightly poorer performance than
 684   before for formats not converted yet.
 685
 686 * Command-line parsing is no longer done with flex.  This means
 687   oddball characters in filenames won't get treated as argument
 688   separators.
 689
 690 * HP-PA ELF support, by Jeff Law.  (No SOM support yet.)
 691
 692 * Mach i386 support, by David Mackenzie.
 693
 694 * Irix 4 shared libraries are now supported (Irix 5 uses ELF, and ELF shared
 695   libraries are not yet supported).
 696
 697 * COFF shared libraries (as on SCO) should work as well.
 698
 699 * The linker is disabled for Solaris.  (Actually, it was in 2.3 also, I just
 700   forgot to note it.)  Some of their C library routines don't work when
 701   statically linked, and the GNU linker doesn't support dynamic linking yet.
 702
 703 Changes in version 2.3:
 704
 705 * Weak symbols are now supported.
 706
 707 * ELF support has been added.  The linker has been bootstrapped on
 708   UnixWare and Solaris.
 709
 710 * Alpha OSF/1 support has been added (non dynamic linking only).
 711
 712 Changes in version 2.2:
 713
 714 * The `bfd' library has been updated to reduce a.out-format string
 715   table size.  The effect of this is that files linked from many input
 716   files with duplicate symbols (`-g' debugging records, or identical
 717   static symbols) should be much smaller.
 718
 719 Changes in version 2.1:
 720
 721 * The ld -ySYMBOL flag (to trace references to SYMBOL) is now implemented.
 722
 723 * There is now support for writing ECOFF files, so ld and the
 724   other utilities should work on Risc/Ultrix and Irix.
 725
 726 \f
 727 Copyright (C) 2012-2018 Free Software Foundation, Inc.
 728
 729 Copying and distribution of this file, with or without modification,
 730 are permitted in any medium without royalty provided the copyright
 731 notice and this notice are preserved.
 732
 733 Local variables:
 734 fill-column: 79
 735 End: