ld/NEWS

   1 -*- text -*-
   2
   3 Changes in 2.32:
   4
   5 * Report property change in linker map file when merging GNU properties.
   6
   7 * Add support for the C-SKY processor series.
   8
   9 Changes in 2.31:
  10
  11 * Speed up direct linking with DLLs for Cygwin and Mingw targets.
  12
  13 * Add a configure option --enable-separate-code to decide whether
  14   -z separate-code should be enabled in ELF linker by default.  Default
  15   to yes for Linux/x86 targets.  Note that -z separate-code can increase
  16   disk and memory size.
  17
  18 Changes in 2.30:
  19
  20 * Add -z separate-code to generate separate code PT_LOAD segment.
  21
  22 * Add "-z undefs" command-line option as the inverse of the "-z defs" option.
  23
  24 * Add -z globalaudit command-line option to force audit libraries to be run
  25   for every dynamic object loaded by an executable - provided that the loader
  26   supports this functionality.
  27
  28 * Tighten linker script grammar around file name specifiers to prevent the use
  29   of SORT_BY_ALIGNMENT and SORT_BY_INIT_PRIORITY on filenames.  These would
  30   previously be accepted but had no effect.
  31
  32 * The EXCLUDE_FILE directive can now be placed within any SORT_* directive
  33   within input section lists.
  34
  35 Changes in 2.29:
  36
  37 * Support for -z shstk in the x86 ELF linker to generate
  38   GNU_PROPERTY_X86_FEATURE_1_SHSTK in ELF GNU program properties.
  39
  40 * Add support for GNU_PROPERTY_X86_FEATURE_1_SHSTK in ELF GNU program
  41   properties in the x86 ELF linker.
  42
  43 * Add support for GNU_PROPERTY_X86_FEATURE_1_IBT in ELF GNU program
  44   properties in the x86 ELF linker.
  45
  46 * Support for -z ibtplt in the x86 ELF linker to generate IBT-enabled
  47   PLT.
  48
  49 * Support for -z ibt in the x86 ELF linker to generate IBT-enabled
  50   PLT as well as GNU_PROPERTY_X86_FEATURE_1_IBT in ELF GNU program
  51   properties.
  52
  53 * Add support for ELF SHF_GNU_MBIND and PT_GNU_MBIND_XXX.
  54
  55 * Add support for ELF GNU program properties.
  56
  57 * Add support for the Texas Instruments PRU processor.
  58
  59 * When configuring for arc*-*-linux* targets the default linker emulation will
  60   change if --with-cpu=nps400 is used at configure time.
  61
  62 * Improve assignment of LMAs to orphan sections in some edge cases where a
  63   mixture of both AT>LMA_REGION and AT(LMA) are used.
  64
  65 * Orphan sections placed after an empty section that has an AT(LMA) will now
  66   take an load memory address starting from LMA.
  67
  68 * Section groups can now be resolved (the group deleted and the group members
  69   placed like normal sections) at partial link time either using the new linker
  70   option --force-group-allocation or by placing FORCE_GROUP_ALLOCATION into the
  71   linker script.
  72
  73 Changes in 2.28:
  74
  75 * The EXCLUDE_FILE linker script construct can now be applied outside of the
  76   section list in order for the exclusions to apply over all input sections in
  77   the list.
  78
  79 * Add support for the RISC-V architecture.
  80
  81 * The command-line option --no-eh-frame-hdr can now be used in ELF based
  82   linkers to disable the automatic generation of .eh_frame_hdr sections.
  83
  84 * Add --in-implib=<infile> to the ARM linker to enable specifying a set of
  85   Secure Gateway veneers that must exist in the output import library specified
  86   by --out-implib=<outfile> and the address they must have.  As such,
  87   --in-implib is only supported in combination with --cmse-implib.
  88
  89 * Extended the --out-implib=<file> option, previously restricted to x86 PE
  90   targets, to any ELF based target.  This allows the generation of an import
  91   library for an ELF executable, which can then be used by another application
  92   to link against the executable.
  93
  94 Changes in 2.27:
  95
  96 * Add a configure option --enable-relro to decide whether -z relro should
  97   be enabled in ELF linker by default.  Default to yes for all Linux
  98   targets except FRV, HPPA, IA64 and MIPS.  Note that -z relro can increase
  99   disk and memory size.
 100
 101 * Support for -z noreloc-overflow in the x86-64 ELF linker to disable
 102   relocation overflow check.
 103
 104 * Add -z common/-z nocommon options for ELF targets to control whether to
 105   convert common symbols to the STT_COMMON type during a relocatable link.
 106
 107 * Support for -z nodynamic-undefined-weak in the x86 ELF linker, which
 108   avoids dynamic relocations against undefined weak symbols in executable.
 109
 110 * The NOCROSSREFSTO command was added to the linker script language.
 111
 112 * Add --no-apply-dynamic-relocs to the AArch64 linker to do not apply link-time
 113   values for dynamic relocations.
 114
 115 Changes in 2.26:
 116
 117 * Add --fix-stm32l4xx-629360 to the ARM linker to enable a link-time
 118   workaround for a bug in the bus matrix / memory controller for some of
 119   the STM32 Cortex-M4 based products (STM32L4xx)
 120
 121 * Add a configure option --enable-compressed-debug-sections={all,ld} to
 122   decide whether DWARF debug sections should be compressed by default.
 123
 124 * Add support for the ARC EM/HS, and ARC600/700 architectures.
 125
 126 * Experimental support for linker garbage collection (--gc-sections)
 127   has been enabled for COFF and PE based targets.
 128
 129 * New command-line option for ELF targets to compress DWARF debug
 130   sections, --compress-debug-sections=[none|zlib|zlib-gnu|zlib-gabi].
 131
 132 * New command-line option, --orphan-handling=[place|warn|error|discard], to
 133   adjust how orphan sections are handled.  The default is 'place' which gives
 134   the current behaviour, 'warn' and 'error' issue a warning or error
 135   respectively when orphan sections are found, and 'discard' will discard all
 136   orphan sections.
 137
 138 * Add support for LLVM plugin.
 139
 140 * Add --print-memory-usage option to report memory blocks usage.
 141
 142 * Add --require-defined option, it's like --undefined except the new symbol
 143   must be defined by the end of the link.
 144
 145 Changes in 2.25:
 146
 147 * PE binaries now once again contain real timestamps by default.  To disable
 148   the inclusion of a timestamp in a PE binary, use the --no-insert-timestamp
 149   command-line option.
 150
 151 * Replace support for openrisc and or32 with support for or1k.
 152
 153 * Add support for the --build-id command-line option to COFF based targets.
 154
 155 * x86/x86_64 pe-coff now supports the --build-id option.
 156
 157 * Add support for the Andes NDS32.
 158
 159 Changes in 2.24:
 160
 161 * Add LOG2CEIL() builtin function to the linker script language
 162
 163 * Add support for the Texas Instruments MSP430X processor.
 164
 165 * Add support for Altera Nios II.
 166
 167 * Add support for the V850E3V5 architecture.
 168
 169 * Add support for the Imagination Technologies Meta processor.
 170
 171 * --enable-new-dtags no longer generates old dtags in addition to new dtags.
 172
 173 * Remove linker support for MIPS ECOFF targets.
 174
 175 * Add ALIGN_WITH_INPUT to the linker script language to force the alignment of
 176   an output section to use the maximum alignment of all its input sections.
 177
 178 Changes in 2.23:
 179
 180 * Enable compressed debug section feature for x86/x86_64 pe-coff.
 181
 182 * Add support for the 64-bit ARM architecture: AArch64.
 183
 184 * Added SORT_NONE to the linker script language to disable section sorting.
 185
 186 * Add a linker-provided symbol when producing ELF output, '__ehdr_start'
 187   to point to the ELF file header (and nearby program headers) in the
 188   program's memory image.
 189
 190 * Add support for S12X processor.
 191
 192 * Add support for the VLE extension to the PowerPC architecture.
 193
 194 * Add support for the Freescale XGATE architecture.
 195
 196 * Add option -f FILE on AIX (for response file).
 197
 198 * Add support for the Renesas RL78 architecture.
 199
 200 * Add support for the Adapteva EPIPHANY architecture.
 201
 202 Changes in 2.22:
 203
 204 * --copy-dt-needed-entries is no longer enabled by default.  Instead
 205   --no-copy-dt-needed-entries is the default.
 206
 207 * INPUT_SECTION_FLAGS has been added to the linker script language
 208   to allow selection of input sections by section header section flags.
 209
 210 * Add support for the Tilera TILEPro and TILE-Gx architectures.
 211
 212 * Added SORT_BY_INIT_PRIORITY to the linker script language to permit
 213   sorting sections by numerical value of the GCC init_priority attribute
 214   encoded in the section name.
 215
 216 Changes in 2.21:
 217
 218 * Linker script expression evaluation is somewhat more sane.  This may
 219   break scripts that depend on quirks of the old expression evaluation.
 220
 221 * Turn off underscoring for x86_64 PE+-COFF targets.  For old behavior the
 222   option --enable-leading-mingw64-underscores can be used on configure of
 223   bfd.
 224
 225 * Add support for the TMS320C6000 (TI C6X) processor family.
 226
 227 * --add-needed renamed to --copy-dt-needed-entries in order to avoid confusion
 228   with --as-needed option.
 229
 230 * Extend .def file syntax by '== <ID>' for imports and exports. This allows
 231   to alias the import/export table name written in PE image.
 232
 233 * Add --exclude-all-symbols option to PE based linkers.  This prevents all
 234   symbols from automatically being exported.
 235
 236 * Add support for the Renesas RX processor.
 237
 238 * Add support for alpha-vms target.
 239
 240 Changes in 2.20:
 241
 242 * GNU/Linux targets now support the STB_GNU_UNIQUE symbol binding.  This is a
 243   GNU extension to the standard set of ELF symbol bindings.  The binding will
 244   be passed on to the dynamic linker which will make sure that in the entire
 245   process there is just one symbol with the given name and type in use.
 246
 247 * PE targets now support a GNU extension to allow the alignment of common
 248   common symbols to be specified.  This support uses custom options in
 249   the .drectve section, which will be disregarded by the native tools.
 250
 251 * PE targets now add primitive support for ELF version scripts; symbols
 252   are not versioned, but the local and global symbol visibility directives
 253   are respected when filtering symbols in auto-export mode.
 254
 255 * New option --no-export-dynamic to undo the effect of the -E and
 256   --export-dynamic options.
 257
 258 * ELF: --warn-alternate-em option to warn if an object has alternate
 259   ELF machine code.
 260
 261 * New script function REGION_ALIAS to add alias names to memory regions.
 262
 263 * PE targets no longer make use of the long section names PE extension to
 264   the COFF format when generating executable images, by default.  The old
 265   (slightly non-conformant) behaviour can still be invoked by using the
 266   new '--enable-long-section-names' command-line option.  It is also enabled
 267   automatically in the presence of un-stripped debug information, as GDB
 268   needs to be able to find the debug info sections by their full names.
 269
 270 * For GNU/Linux systems the linker will now avoid processing any relocations
 271   made against symbols of the STT_GNU_IFUNC type and instead emit them into
 272   the resulting binary for processing by the loader.
 273
 274 * --as-needed now links in a dynamic library if it satisfies undefined
 275   symbols in regular objects, or in other dynamic libraries.  In the
 276   latter case the library is not linked if it is found in a DT_NEEDED
 277   entry of one of the libraries already linked.
 278
 279 * Add a new command-line option, -Ttext-segment ADDR, for ELF targets
 280   to set the address of the first byte of the text segment.
 281
 282 * Add support for Sunplus score architecture.
 283
 284 * Add new option --use-nul-prefixed-import-tables to ld for PE targets to
 285   allow fallback to old import table generation with null element prefix.
 286
 287 * Windows PE systems now support a new --exclude-modules-for-implib option,
 288   allowing users to partition object files and archive members between a DLL
 289   and its associated import library as they are generated during linking.
 290
 291 * Add support for Lattice Mico32 (lm32) architecture.
 292
 293 * Add CR16 ELF --embedded-relocs (used to embedded relocations into binaries
 294   for Embedded-PIC code) option.
 295
 296 * Add to the PE/PE+ targets the support of two different kinds of
 297   pseudo-relocations.  They can be selected by the switches
 298   --enable-runtime-pseudo-reloc-v1 and --enable-runtime-pseudo-reloc-v2.
 299   For the switch --enable-runtime-pseudo-reloc it uses for 32-bit
 300   runtime pseudo relocation version one, for 64-bit the version two.
 301
 302 Changes in 2.19:
 303
 304 * Linker scripts support a new INSERT command that makes it easier to
 305   augment the default script.
 306
 307 * Linker script input section filespecs may now specify a file within an
 308   archive by writing "archive:file".
 309
 310 * The --sort-common switch now has an optional argument which specifies the
 311   direction of sorting.
 312
 313 * The M68K linker now supports multiple GOT generation schemes controlled via
 314   the --got=<type> command-line option.
 315
 316 * The ARM EABI linker will now generate stubs for function calls to symbols
 317   that are too far away.  The placement of the stubs is controlled by a new
 318   linker command-line option: --stub-group-size=N.
 319
 320 Changes in 2.18:
 321
 322 * Linker sources now released under version 3 of the GNU General Public
 323   License.
 324
 325 * ELF: New --build-id option to generate a unique per-binary identifier
 326   embedded in a note section.
 327
 328 * Added support for National Semicondutor CompactRISC (ie CR16) target.
 329
 330 * -l:foo now searches the library path for a filename called foo,
 331   without converting it to libfoo.a or libfoo.so.
 332
 333 * Add a new command-line option '--default-script=FILE' or '-dT FILE'
 334   which specifies a replacement for the built in, default linker
 335   script.
 336
 337 * ELF: Add -Bsymbolic-functions, --dynamic-list-cpp-new, which puts C++
 338   operator new and delete on the dynamic list, and --dynamic-list-data,
 339   builtin list for --dynamic-list, which puts global data symbols on the
 340   dynamic list.
 341
 342 * Add support for x86_64 PE+ target.
 343
 344 * Add support for Score target.
 345
 346 * ELF: Add --dynamic-list option to specify a list of global symbols
 347   whose references shouldn't be bound to the definition within the
 348   shared library, or a list of symbols which should be added to the
 349   symbol table in the executable.
 350
 351 * The default output section LMA has changed for allocatable sections from
 352   being equal to VMA, to keeping the difference between LMA and VMA the same as
 353   the previous output section in the same region.  This is a more useful
 354   default when using overlays and other cases where you specify an LMA
 355   differing from the VMA for some sections.
 356
 357 * New switch: --print-gc-sections to list any sections removed by garabge
 358   collection.
 359
 360 * ARM: Added --vfp11-denorm-fix option to work around an erratum in current
 361   VFP11 coprocessors.
 362
 363 Changes in 2.17:
 364
 365 * Support for the Infineon XC16X has been added by KPIT Cummins Infosystems.
 366
 367 * Modify the Linux linker search order to better match ld.so search order.
 368   Look for DT_NEEDED libraries in paths specified by ld.so.conf before
 369   searching the default directories, rather than vice versa.
 370   Use $prefix/etc/ld.so.conf if it exists, otherwise /etc/ld.so.conf.
 371
 372 * PE-COFF: Forward exports from DLL's can now be specified in .def files
 373   passed directly to ld.
 374
 375 * Support for the Z80 processor family has been added.
 376
 377 * Add support for the "@<file>" syntax to the command line, so that extra
 378   switches can be read from <file>.
 379
 380 Changes in 2.16:
 381
 382 * Support for the R_ARM_V4BX relocation as defined in the ARM AAELF
 383   specification has been added via the --fix-v4bx command-line option.
 384
 385 * New linker script construct AS_NEEDED(), which sets the --as-needed flag
 386   for input files listed inside of it.
 387
 388 * A new command-line option, --sysroot, can be used to override the
 389   default sysroot location.  It only applies to toolchains that were
 390   configured using --with-sysroot.
 391
 392 * New linker script functions: ORIGIN() and LENGTH() which return information
 393   about a specified memory region.
 394
 395 * Port to MAXQ processor contributed by HCL Tech.
 396
 397 * Added SEGMENT_START to the linker script language to permit the user to
 398   override the base address for a segment from the command-line.
 399
 400 * ELF: --warn-shared-textrel option to warn if adding a DT_TEXTREL to a shared
 401   object.
 402
 403 * Added SORT_BY_NAME and SORT_BY_ALIGNMENT to the linker script
 404   language to permit sorting sections by section name or section
 405   maximum alignment.
 406
 407 * Added a new linker command-line switch, --sort-section name|alignment,
 408   to sort sections by section name or maximum alignment.
 409
 410 * ELF: --add-needed/--no-add-needed options to control if a DT_NEEDED tag
 411   should be added when a shared library comes from DT_NEEDED tags.
 412
 413 * Support for the crx-elf target added.
 414
 415 * Support for the sh-symbianelf target added.
 416
 417 * A new linker command-line switch has been added which allows the hash table
 418   size to be set to a suitable prime value near to its argument.  This switch
 419   is --hash-size=<NUMBER>.  Also if the switch --reduce-memory-overheads is
 420   used, and --hash-size has not been used, then the default value will be set
 421   to 1021.
 422
 423 * Linker map files are now generated with an O(N) algorithm for finding symbols
 424   that are defined in each section.  This uses about 40% more memory for
 425   symbols than the old O(N^2) algorithm.  You can use the new
 426   --reduce-memory-overheads option to select the old algorithm; this option
 427   might also be used in the future to select similar tradeoffs.
 428
 429 Changes in 2.15:
 430
 431 * ELF: --as-needed/--no-as-needed options to control if a DT_NEEDED tag should
 432   be added only when a shared library is referenced.
 433
 434 * PE: --large-address-aware option to indicate executables support virtual
 435   addresses greater than 2 gigabytes.
 436
 437 * DWARF 2 support for i386pe added.
 438
 439 * The linker script operator DEFINED() will now yield 1 only for a symbol that
 440   is defined before the statement where DEFINED is used.
 441
 442 * The MIPS --embedded-relocs (used to embed relocations into binaries for
 443   Embedded-PIC code) is deprecated and will be removed in a future release.
 444
 445 * cr16c support added by NSC.
 446
 447 * m32r Linux (ELF) support added by Renesas.
 448
 449 * Improved linker's handling of unresolved symbols.  The switch
 450   --unresolved-symbols=<method> has been added to tell the linker when it
 451   should report them and the switch --warn-unresolved-symbols has been added to
 452   make reports be issued as warning messages rather than errors.
 453
 454 Changes in 2.14:
 455
 456 * Added support for Xtensa architecture.
 457
 458 * Added --with-sysroot configure switch to specify a target system root, for
 459   linking against a target filesystem image.
 460
 461 * Added --accept-unknown-linker-format to restore old linker behaviour (pre
 462   2.14) of silently accepting and linking in any files in an unknown binary
 463   file format.
 464
 465 * Added --no-omagic to undo the effects of the -N option.
 466
 467 * Support for Texas Instruments TMS320C4x and TMS320C3x series of
 468   DSP's contributed by Michael Hayes and Svein E. Seldal.
 469
 470 * Added --with-lib-path configure switch to specify default value for
 471   LIB_PATH.
 472
 473 * ARM port to QNX operating system added by Graeme Peterson.
 474
 475 * IP2K support added by Denis Chertykov.
 476
 477 Changes in 2.13:
 478
 479 * Support for the Fujitsu FRV architecture added by Red Hat. Models for FR400
 480   and FR500 included.
 481
 482 Changes in version 2.13:
 483
 484 * DEC VAX ELF support, by Matt Thomas.
 485
 486 Changes in version 2.12:
 487
 488 * Support for Don Knuth's MMIX, by Hans-Peter Nilsson.
 489
 490 * Support for the OpenRISC 32-bit embedded processor by OpenCores.
 491
 492 * Support for -z nocopyreloc in the x86 ELF linker, which disables
 493   production of copy relocs.  Warning: using this option may result in
 494   non-sharable applications.
 495
 496 * Support for -z combreloc in the ELF linker, which puts dynamic
 497   relocations against the same symbol together, so that dynamic linker
 498   can use an one-entry symbol lookup cache.
 499
 500 * Support for ELF SHF_MERGE section merging, by Jakub Jelinek.
 501
 502 Changes in version 2.11:
 503
 504 * Support for AMD x86-64 architecture, by Jan Hubicka, SuSE Labs.
 505
 506 * Support added for eliminating duplicate DWARF2 debug information by
 507   having the compiler generate the information in sections called
 508   .gnu.linkonce.wi.XXXX where XXXX is a checksum for the contents.  The
 509   linker then merges these sections together into the normal .debug_info
 510   section.
 511
 512 * The native ELF linker now searches the directories in DT_RUNPATH or
 513   DT_RPATH of a shared library for shared libraries needed by it.
 514
 515 * TI C54x support, by Timothy Wall.
 516
 517 * Added command-line switch --section-start to set the start address of any
 518   specified section.
 519
 520 * Added ability to emit full relocation information in linked executables,
 521   enabled by --emit-relocs.  Some post-linkage optimization tools need
 522   this information in order to be able to correctly identify and perform
 523   symbol relative addressing in the event of changes in section contents
 524   (instructions being added or deleted, extending data sections, etc.)
 525
 526 * Support for i860, by Jason Eckhardt (preliminary, alpha quality).
 527
 528 * Support for CRIS (Axis Communications ETRAX series).
 529
 530 * Support for PDP-11 and 2.11BSD a.out format, by Lars Brinkhoff.
 531
 532 Changes in version 2.10:
 533
 534 * Added AT> to the linker script language to allow load-time allocation of
 535   sections into regions.
 536
 537 * Added garbage collection of unused sections, enabled by --gc-sections.
 538   It does require a bit of backend support; currently implemented are
 539   arm-elf, avr-elf, d10v-elf, fr30-elf, i386-elf, m32r-elf, m68k-elf,
 540   mcore-elf, mips-elf, mn10300-elf, ppc-elf, sh-elf, sparc-elf, and v850-elf.
 541   Others will ignore the option.
 542
 543 * Added SORT to the linker script language to permit sorting sections by file
 544   name or section name.
 545
 546 * Added EXTERN to the linker script language as an equivalent to the -u
 547   command-line option.
 548
 549 * Added ASSERT to the linker script language.
 550
 551 * Added EXCLUDE_FILE to the linker script language for further control over
 552   wildcard file names.
 553
 554 * Added -O option to optimize linker output (as of this writing, this only
 555   affects ELF shared library generation).
 556
 557 * The -e option now accepts a number as well as a symbol name.
 558
 559 * Added --no-undefined option to disallow undefined symbols when creating a
 560   shared library.
 561
 562 * The linker now issues a warning, not an error, for an undefined symbol when
 563   using -Bsymbolic; use the new --no-undefined option to get the old
 564   behaviour.
 565
 566 * Added --demangle and --no-demangle options.
 567
 568 Changes in version 2.9:
 569
 570 * Added SQUAD to the linker script language.
 571
 572 * New option --no-warn-mismatch.
 573
 574 * The MEMORY command now parses the attributes to determine where sections that
 575   are not placed in a specific memory region are placed.
 576
 577 Changes in version 2.8:
 578
 579 * Linker scripts may now contain shell wildcard characters for file and section
 580   names.
 581
 582 * The linker now supports symbol versions in ELF.
 583
 584 * The NOCROSSREFS command was added to the linker script language.
 585
 586 * The LOADADDR expression was added to the linker script language.
 587
 588 * MAX and MIN functions were added to the linker script language.
 589
 590 * The OVERLAY construct was added to the linker script language.
 591
 592 * New option --warn-section-align to warn when the address of an output section
 593   changes due to alignment of an input section.
 594
 595 * New options --filter/-F and --auxiliary/-f.
 596
 597 Changes in version 2.7:
 598
 599 * New option --cref to print out a cross reference table.
 600
 601 * New option --wrap SYMBOL.
 602
 603 * New option --no-whole-archive, to turn off the effect of --whole-archive.
 604
 605 * Input sections assigned to the output section /DISCARD/ in the linker script
 606   are not included in the output file.
 607
 608 * The SunOS and ELF linkers now merge stabs debugging information which uses
 609   the N_BINCL and N_EINCL stab types.  This reduces the amount of debugging
 610   information generated.
 611
 612 Changes in version 2.6:
 613
 614 * When an ELF section name is representable as a C identifier (this is not true
 615 of most ELF section names), the linker will automatically define symbols
 616 __start_SECNAME and __stop_SECNAME, where SECNAME is the section name, at the
 617 beginning and the end of the section.  This is used by glibc.
 618
 619   Addendum: Current versions of the linker (at least for version 2.18 onwards
 620 and possibly much earlier as well) place two restrictions on this feature:  The
 621 symbols are only implemented for orphaned sections, not for explicitly placed
 622 sections and they are PROVIDEd rather than being defined.
 623
 624 * When an ELF section named .gnu.warning is encountered in an input file, the
 625 contents of the section are displayed as an error message, and the section is
 626 not copied into the output file.  This is used by glibc.
 627
 628 * When an ELF section named .gnu.warning.SYMBOL is encountered in an input
 629 file, and the symbol SYMBOL is referenced by some object file, the contents of
 630 the section are displayed as an error message.  The section is not copied into
 631 the output file, unless doing a relocatable or shared link.  This is used by
 632 glibc.
 633
 634 * New options -split-by-reloc and -split-by-file.
 635
 636 * The linker now supports linking PIC compiled code on SPARC SunOS.  It can
 637 also create SPARC SunOS shared libraries, and, like the native SunOS linker,
 638 will do so whenever there is an undefined symbol in the link and neither the -e
 639 nor the -r option was used.
 640
 641 * The -rpath option may be used on SunOS to set the list of directories to be
 642 searched at run time.  This overrides the default of building the list from the
 643 -L options.
 644
 645 * The COFF linker now combines debugging information for structs, unions, and
 646 enums, so that even if the same type is defined in multiple input files it will
 647 only be defined once in the output file.  The --traditional-format switch will
 648 prevent this optimization.
 649
 650 Changes in version 2.5:
 651
 652 * The linker now supports linking against SunOS shared libraries.  It still can
 653 not link SunOS PIC (Position Independent Code) files, so it can not be used to
 654 generate shared libraries.
 655
 656 * The linker now supports linking against ELF shared libraries for the i386
 657 (UnixWare) and SPARC (Solaris).  It can also link ELF PIC files, and can be
 658 used to generate shared libraries.  Shared library generation is not well
 659 tested; please report any problems encountered.  The linker is now enabled for
 660 Solaris again.
 661
 662 * Eric Youngdale has contributed Linux support code, including linking against
 663 Linux a.out shared libraries.  The linker produces Linux QMAGIC binaries.
 664
 665 * The ELF backend has been converted to the new linker code.  To use the new
 666 ELF linker, each particular target requires a relocation function.  So far,
 667 this function has been written for i386 (UnixWare), SPARC (Solaris) MIPS (Irix
 668 5), and HPPA ELF targets.
 669
 670 * The -( (--start-group) and -) (--end-group) options have been added to
 671 support searching a group of archives as though they were a single archive.
 672 This can also be used in a linker script, as GROUP ( files ).
 673
 674 * When a file is named on the command line, and the linker does not recognize
 675 it as an object file, the linker will now treat the file as a linker script
 676 file.  A linker script named in this way augments, but does not replace, the
 677 default linker script.
 678
 679 * The -warn-once option was added.  It causes the linker to only warn once per
 680 undefined symbol, rather than once per reference.
 681
 682 * The COFF backend has been converted to the new linker code.  As with ELF, to
 683 use the new linker, each particular target requires a relocation function.  So
 684 far, this function has been written for the i386, m68k, a29k and SH targets.
 685
 686 * The -V flag was made a synonym for -v, for SVR4 compatibility.  The old -V
 687 behaviour is available via --verbose.
 688
 689 Changes in version 2.4:
 690
 691 * New linker code, by Steve Chamberlain and Ian Taylor.  For a.out and ecoff
 692   formats (so far), this should result in considerable savings in time
 693   and memory used while linking; slightly poorer performance than
 694   before for formats not converted yet.
 695
 696 * Command-line parsing is no longer done with flex.  This means
 697   oddball characters in filenames won't get treated as argument
 698   separators.
 699
 700 * HP-PA ELF support, by Jeff Law.  (No SOM support yet.)
 701
 702 * Mach i386 support, by David Mackenzie.
 703
 704 * Irix 4 shared libraries are now supported (Irix 5 uses ELF, and ELF shared
 705   libraries are not yet supported).
 706
 707 * COFF shared libraries (as on SCO) should work as well.
 708
 709 * The linker is disabled for Solaris.  (Actually, it was in 2.3 also, I just
 710   forgot to note it.)  Some of their C library routines don't work when
 711   statically linked, and the GNU linker doesn't support dynamic linking yet.
 712
 713 Changes in version 2.3:
 714
 715 * Weak symbols are now supported.
 716
 717 * ELF support has been added.  The linker has been bootstrapped on
 718   UnixWare and Solaris.
 719
 720 * Alpha OSF/1 support has been added (non dynamic linking only).
 721
 722 Changes in version 2.2:
 723
 724 * The `bfd' library has been updated to reduce a.out-format string
 725   table size.  The effect of this is that files linked from many input
 726   files with duplicate symbols (`-g' debugging records, or identical
 727   static symbols) should be much smaller.
 728
 729 Changes in version 2.1:
 730
 731 * The ld -ySYMBOL flag (to trace references to SYMBOL) is now implemented.
 732
 733 * There is now support for writing ECOFF files, so ld and the
 734   other utilities should work on Risc/Ultrix and Irix.
 735
 736 \f
 737 Copyright (C) 2012-2019 Free Software Foundation, Inc.
 738
 739 Copying and distribution of this file, with or without modification,
 740 are permitted in any medium without royalty provided the copyright
 741 notice and this notice are preserved.
 742
 743 Local variables:
 744 fill-column: 79
 745 End: