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1 -*- text -*-
2
3 * Add support for the LoongArch architecture.
4
5 * Add -z indirect-extern-access/-z noindirect-extern-access to x86 ELF
6 linker to control canonical function pointers and copy relocation.
7
8 * Add --max-cache-size=SIZE to set the the maximum cache size to SIZE
9 bytes.
10
11 Changes in 2.37:
12
13 * arm-symbianelf support removed.
14
15 * Add -z report-relative-reloc to x86 ELF linker to report dynamic
16 relative relocations.
17
18 * Add -z start-stop-gc to disable special treatment of __start_*/__stop_*
19 references when --gc-sections.
20
21 * Add -Bno-symbolic to cancel -Bsymbolic and -Bsymbolic-functions.
22
23 Changes in 2.36:
24
25 * Add libdep plugin, for linking dependencies of static libraries that
26 were recorded by ar in the __.LIBDEP archive member.
27
28 * Add --error-handling-script=<NAME> command line option to allow a helper
29 script to be invoked when an undefined symbol or a missing library is
30 encountered. This option can be suppressed via the configure time
31 switch: --enable-error-handling-script=no.
32
33 * Add -z lam-u48 to x86-64 ELF linker to generate LAM_U48 property.
34
35 * Add -z lam-u57 to x86-64 ELF linker to enerate LAM_U57 property.
36
37 * Add -z lam-u48-report=[none|warning|error] to report missing LAM_U48
38 property.
39
40 * Add -z lam-u57-report=[none|warning|error] to report missing LAM_U57
41 property.
42
43 * Add -z lam-report=[none|warning|error] to report missing LAM_U48 and
44 LAM_U57 properties.
45
46 * Add -z x86-64-{baseline|v[234]} to the x86 ELF linker to mark
47 x86-64-{baseline|v[234]} ISA level as needed.
48
49 * Add -z unique-symbol to avoid duplicated local symbol names.
50
51 * The creation of PE format DLLs now defaults to using a more secure set of DLL
52 characteristics.
53
54 * The linker now deduplicates the types in .ctf sections. The new
55 command-line option --ctf-share-types describes how to do this:
56 its default value, share-unconflicted, produces the most compact
57 output.
58
59 * The linker now omits the "variable section" from .ctf sections by
60 default, saving space. This is almost certainly what you want
61 unless you are working on a project that has its own analogue
62 of symbol tables that are not reflected in the ELF symtabs.
63
64 * Add support for the SHF_GNU_RETAIN ELF section flag.
65 This flag specifies that the section should not be garbage collected by the
66 linker.
67
68 Changes in 2.35:
69
70 * X86 NaCl target support is removed.
71
72 * Add ELF linker command-line options, --export-dynamic-symbol and
73 --export-dynamic-symbol-list, to make symbols dynamic.
74
75 * Add a configure option, --enable-textrel-check=[no|yes|warning|error],
76 to decide what ELF linker should do by default with DT_TEXTREL in an
77 executable or shared library. Default to yes for Linux/x86 targets.
78
79 * The -Map=<filename> command line option has been extended so that if
80 <filename> is a directory then <filename>/<output-filename>.map will be
81 created.
82
83 * Add a command-line option for ELF linker, --warn-textrel, to warn that
84 DT_TEXTREL is set in a position-independent executable or shared object.
85
86 * Add command-line options --enable-non-contiguous-regions and
87 --enable-non-contiguous-regions-warnings.
88
89 * Add command-line option --imagic for the pdp11-aout target to output format
90 IMAGIC (0411) for separate instruction and data spaces, and change the
91 default format option for pdp11-aout to be --omagic.
92
93 * Relative pathnames in INPUT() and GROUP() directives in linker scripts are
94 searched relative to the directory of the linker script before other search
95 paths.
96
97 * Add ELF linker command-line option `-z start-stop-visibility=...' to control
98 the visibility of synthetic `__start_SECNAME` and `__stop_SECNAME` symbols.
99
100 * Add command-line option --dependency-file to write a Make-style dependency
101 file listing the input files consulted by the linker, like the files written
102 by the compiler's -M -MP options.
103
104 Changes in 2.34:
105
106 * The ld check for "PHDR segment not covered by LOAD segment" is more
107 effective, catching cases that were wrongly allowed by previous versions of
108 ld. If you see this error it is likely you are linking with a bad linker
109 script or the binary you are building is not intended to be loaded by a
110 dynamic loader. In the latter case --no-dynamic-linker is appropriate.
111
112 * cr16c support removed.
113
114 * Add support for z80-elf.
115
116 * Add support for relocation of each byte or word of multibyte value to Z80
117 targets.
118
119 * Add support for Zilog eZ80 (both ADL and Z80 mode) and Zilog Z180 CPUs.
120
121 Changes in 2.33:
122
123 * Add command-line option --no-print-map-discarded.
124
125 * The Cortex-A53 Erratum 843419 workaround now supports a choice of which
126 workaround to use. The option --fix-cortex-a53-843419 now takes an
127 optional argument --fix-cortex-a53-843419[=full|adr|adrp] which can be
128 used to force a particular workaround to be used. See --help for AArch64
129 for more details.
130
131 * Add target handlers for AArch64 for ELF GNU program properties.
132
133 * Add support for GNU_PROPERTY_AARCH64_FEATURE_1_BTI in ELF GNU program
134 properties in the AArch64 ELF linker.
135
136 * Add support for GNU_PROPERTY_AARCH64_FEATURE_1_PAC in ELF GNU program
137 properties in the AArch64 ELF linker.
138
139 * Add -z force-bti for AArch64 to enable GNU_PROPERTY_AARCH64_FEATURE_1_BTI
140 on output while warning about missing GNU_PROPERTY_AARCH64_FEATURE_1_BTI
141 on inputs and use PLTs protected with BTI.
142
143 * Add -z pac-plt for AArch64 to pick PAC enabled PLTs.
144
145 Changes in 2.32:
146
147 * Report property change in linker map file when merging GNU properties.
148
149 * Add support for the C-SKY processor series.
150
151 * -t now doesn't report members within archives, unless -t is given twice.
152 A single -t is now more useful when generating a list of files that should be
153 packaged for a linker bug report. For example:
154 gcc hello.c -save-temps -Wl,-t | xargs realpath | sort | uniq > files
155 tar cJf test.tar.xz `cat files`
156
157 Changes in 2.31:
158
159 * Speed up direct linking with DLLs for Cygwin and Mingw targets.
160
161 * Add a configure option --enable-separate-code to decide whether
162 -z separate-code should be enabled in ELF linker by default. Default
163 to yes for Linux/x86 targets. Note that -z separate-code can increase
164 disk and memory size.
165
166 Changes in 2.30:
167
168 * Add -z separate-code to generate separate code PT_LOAD segment.
169
170 * Add "-z undefs" command-line option as the inverse of the "-z defs" option.
171
172 * Add -z globalaudit command-line option to force audit libraries to be run
173 for every dynamic object loaded by an executable - provided that the loader
174 supports this functionality.
175
176 * Tighten linker script grammar around file name specifiers to prevent the use
177 of SORT_BY_ALIGNMENT and SORT_BY_INIT_PRIORITY on filenames. These would
178 previously be accepted but had no effect.
179
180 * The EXCLUDE_FILE directive can now be placed within any SORT_* directive
181 within input section lists.
182
183 Changes in 2.29:
184
185 * Support for -z shstk in the x86 ELF linker to generate
186 GNU_PROPERTY_X86_FEATURE_1_SHSTK in ELF GNU program properties.
187
188 * Add support for GNU_PROPERTY_X86_FEATURE_1_SHSTK in ELF GNU program
189 properties in the x86 ELF linker.
190
191 * Add support for GNU_PROPERTY_X86_FEATURE_1_IBT in ELF GNU program
192 properties in the x86 ELF linker.
193
194 * Support for -z ibtplt in the x86 ELF linker to generate IBT-enabled
195 PLT.
196
197 * Support for -z ibt in the x86 ELF linker to generate IBT-enabled
198 PLT as well as GNU_PROPERTY_X86_FEATURE_1_IBT in ELF GNU program
199 properties.
200
201 * Add support for ELF SHF_GNU_MBIND and PT_GNU_MBIND_XXX.
202
203 * Add support for ELF GNU program properties.
204
205 * Add support for the Texas Instruments PRU processor.
206
207 * When configuring for arc*-*-linux* targets the default linker emulation will
208 change if --with-cpu=nps400 is used at configure time.
209
210 * Improve assignment of LMAs to orphan sections in some edge cases where a
211 mixture of both AT>LMA_REGION and AT(LMA) are used.
212
213 * Orphan sections placed after an empty section that has an AT(LMA) will now
214 take an load memory address starting from LMA.
215
216 * Section groups can now be resolved (the group deleted and the group members
217 placed like normal sections) at partial link time either using the new linker
218 option --force-group-allocation or by placing FORCE_GROUP_ALLOCATION into the
219 linker script.
220
221 Changes in 2.28:
222
223 * The EXCLUDE_FILE linker script construct can now be applied outside of the
224 section list in order for the exclusions to apply over all input sections in
225 the list.
226
227 * Add support for the RISC-V architecture.
228
229 * The command-line option --no-eh-frame-hdr can now be used in ELF based
230 linkers to disable the automatic generation of .eh_frame_hdr sections.
231
232 * Add --in-implib=<infile> to the ARM linker to enable specifying a set of
233 Secure Gateway veneers that must exist in the output import library specified
234 by --out-implib=<outfile> and the address they must have. As such,
235 --in-implib is only supported in combination with --cmse-implib.
236
237 * Extended the --out-implib=<file> option, previously restricted to x86 PE
238 targets, to any ELF based target. This allows the generation of an import
239 library for an ELF executable, which can then be used by another application
240 to link against the executable.
241
242 Changes in 2.27:
243
244 * Add a configure option --enable-relro to decide whether -z relro should
245 be enabled in ELF linker by default. Default to yes for all Linux
246 targets except FRV, HPPA, IA64 and MIPS. Note that -z relro can increase
247 disk and memory size.
248
249 * Support for -z noreloc-overflow in the x86-64 ELF linker to disable
250 relocation overflow check.
251
252 * Add -z common/-z nocommon options for ELF targets to control whether to
253 convert common symbols to the STT_COMMON type during a relocatable link.
254
255 * Support for -z nodynamic-undefined-weak in the x86 ELF linker, which
256 avoids dynamic relocations against undefined weak symbols in executable.
257
258 * The NOCROSSREFSTO command was added to the linker script language.
259
260 * Add --no-apply-dynamic-relocs to the AArch64 linker to do not apply link-time
261 values for dynamic relocations.
262
263 Changes in 2.26:
264
265 * Add --fix-stm32l4xx-629360 to the ARM linker to enable a link-time
266 workaround for a bug in the bus matrix / memory controller for some of
267 the STM32 Cortex-M4 based products (STM32L4xx)
268
269 * Add a configure option --enable-compressed-debug-sections={all,ld} to
270 decide whether DWARF debug sections should be compressed by default.
271
272 * Add support for the ARC EM/HS, and ARC600/700 architectures.
273
274 * Experimental support for linker garbage collection (--gc-sections)
275 has been enabled for COFF and PE based targets.
276
277 * New command-line option for ELF targets to compress DWARF debug
278 sections, --compress-debug-sections=[none|zlib|zlib-gnu|zlib-gabi].
279
280 * New command-line option, --orphan-handling=[place|warn|error|discard], to
281 adjust how orphan sections are handled. The default is 'place' which gives
282 the current behaviour, 'warn' and 'error' issue a warning or error
283 respectively when orphan sections are found, and 'discard' will discard all
284 orphan sections.
285
286 * Add support for LLVM plugin.
287
288 * Add --print-memory-usage option to report memory blocks usage.
289
290 * Add --require-defined option, it's like --undefined except the new symbol
291 must be defined by the end of the link.
292
293 Changes in 2.25:
294
295 * PE binaries now once again contain real timestamps by default. To disable
296 the inclusion of a timestamp in a PE binary, use the --no-insert-timestamp
297 command-line option.
298
299 * Replace support for openrisc and or32 with support for or1k.
300
301 * Add support for the --build-id command-line option to COFF based targets.
302
303 * x86/x86_64 pe-coff now supports the --build-id option.
304
305 * Add support for the Andes NDS32.
306
307 Changes in 2.24:
308
309 * Add LOG2CEIL() builtin function to the linker script language
310
311 * Add support for the Texas Instruments MSP430X processor.
312
313 * Add support for Altera Nios II.
314
315 * Add support for the V850E3V5 architecture.
316
317 * Add support for the Imagination Technologies Meta processor.
318
319 * --enable-new-dtags no longer generates old dtags in addition to new dtags.
320
321 * Remove linker support for MIPS ECOFF targets.
322
323 * Add ALIGN_WITH_INPUT to the linker script language to force the alignment of
324 an output section to use the maximum alignment of all its input sections.
325
326 Changes in 2.23:
327
328 * Enable compressed debug section feature for x86/x86_64 pe-coff.
329
330 * Add support for the 64-bit ARM architecture: AArch64.
331
332 * Added SORT_NONE to the linker script language to disable section sorting.
333
334 * Add a linker-provided symbol when producing ELF output, '__ehdr_start'
335 to point to the ELF file header (and nearby program headers) in the
336 program's memory image.
337
338 * Add support for S12X processor.
339
340 * Add support for the VLE extension to the PowerPC architecture.
341
342 * Add support for the Freescale XGATE architecture.
343
344 * Add option -f FILE on AIX (for response file).
345
346 * Add support for the Renesas RL78 architecture.
347
348 * Add support for the Adapteva EPIPHANY architecture.
349
350 Changes in 2.22:
351
352 * --copy-dt-needed-entries is no longer enabled by default. Instead
353 --no-copy-dt-needed-entries is the default.
354
355 * INPUT_SECTION_FLAGS has been added to the linker script language
356 to allow selection of input sections by section header section flags.
357
358 * Add support for the Tilera TILEPro and TILE-Gx architectures.
359
360 * Added SORT_BY_INIT_PRIORITY to the linker script language to permit
361 sorting sections by numerical value of the GCC init_priority attribute
362 encoded in the section name.
363
364 Changes in 2.21:
365
366 * Linker script expression evaluation is somewhat more sane. This may
367 break scripts that depend on quirks of the old expression evaluation.
368
369 * Turn off underscoring for x86_64 PE+-COFF targets. For old behavior the
370 option --enable-leading-mingw64-underscores can be used on configure of
371 bfd.
372
373 * Add support for the TMS320C6000 (TI C6X) processor family.
374
375 * --add-needed renamed to --copy-dt-needed-entries in order to avoid confusion
376 with --as-needed option.
377
378 * Extend .def file syntax by '== <ID>' for imports and exports. This allows
379 to alias the import/export table name written in PE image.
380
381 * Add --exclude-all-symbols option to PE based linkers. This prevents all
382 symbols from automatically being exported.
383
384 * Add support for the Renesas RX processor.
385
386 * Add support for alpha-vms target.
387
388 Changes in 2.20:
389
390 * GNU/Linux targets now support the STB_GNU_UNIQUE symbol binding. This is a
391 GNU extension to the standard set of ELF symbol bindings. The binding will
392 be passed on to the dynamic linker which will make sure that in the entire
393 process there is just one symbol with the given name and type in use.
394
395 * PE targets now support a GNU extension to allow the alignment of common
396 common symbols to be specified. This support uses custom options in
397 the .drectve section, which will be disregarded by the native tools.
398
399 * PE targets now add primitive support for ELF version scripts; symbols
400 are not versioned, but the local and global symbol visibility directives
401 are respected when filtering symbols in auto-export mode.
402
403 * New option --no-export-dynamic to undo the effect of the -E and
404 --export-dynamic options.
405
406 * ELF: --warn-alternate-em option to warn if an object has alternate
407 ELF machine code.
408
409 * New script function REGION_ALIAS to add alias names to memory regions.
410
411 * PE targets no longer make use of the long section names PE extension to
412 the COFF format when generating executable images, by default. The old
413 (slightly non-conformant) behaviour can still be invoked by using the
414 new '--enable-long-section-names' command-line option. It is also enabled
415 automatically in the presence of un-stripped debug information, as GDB
416 needs to be able to find the debug info sections by their full names.
417
418 * For GNU/Linux systems the linker will now avoid processing any relocations
419 made against symbols of the STT_GNU_IFUNC type and instead emit them into
420 the resulting binary for processing by the loader.
421
422 * --as-needed now links in a dynamic library if it satisfies undefined
423 symbols in regular objects, or in other dynamic libraries. In the
424 latter case the library is not linked if it is found in a DT_NEEDED
425 entry of one of the libraries already linked.
426
427 * Add a new command-line option, -Ttext-segment ADDR, for ELF targets
428 to set the address of the first byte of the text segment.
429
430 * Add support for Sunplus score architecture.
431
432 * Add new option --use-nul-prefixed-import-tables to ld for PE targets to
433 allow fallback to old import table generation with null element prefix.
434
435 * Windows PE systems now support a new --exclude-modules-for-implib option,
436 allowing users to partition object files and archive members between a DLL
437 and its associated import library as they are generated during linking.
438
439 * Add support for Lattice Mico32 (lm32) architecture.
440
441 * Add CR16 ELF --embedded-relocs (used to embedded relocations into binaries
442 for Embedded-PIC code) option.
443
444 * Add to the PE/PE+ targets the support of two different kinds of
445 pseudo-relocations. They can be selected by the switches
446 --enable-runtime-pseudo-reloc-v1 and --enable-runtime-pseudo-reloc-v2.
447 For the switch --enable-runtime-pseudo-reloc it uses for 32-bit
448 runtime pseudo relocation version one, for 64-bit the version two.
449
450 Changes in 2.19:
451
452 * Linker scripts support a new INSERT command that makes it easier to
453 augment the default script.
454
455 * Linker script input section filespecs may now specify a file within an
456 archive by writing "archive:file".
457
458 * The --sort-common switch now has an optional argument which specifies the
459 direction of sorting.
460
461 * The M68K linker now supports multiple GOT generation schemes controlled via
462 the --got=<type> command-line option.
463
464 * The ARM EABI linker will now generate stubs for function calls to symbols
465 that are too far away. The placement of the stubs is controlled by a new
466 linker command-line option: --stub-group-size=N.
467
468 Changes in 2.18:
469
470 * Linker sources now released under version 3 of the GNU General Public
471 License.
472
473 * ELF: New --build-id option to generate a unique per-binary identifier
474 embedded in a note section.
475
476 * Added support for National Semicondutor CompactRISC (ie CR16) target.
477
478 * -l:foo now searches the library path for a filename called foo,
479 without converting it to libfoo.a or libfoo.so.
480
481 * Add a new command-line option '--default-script=FILE' or '-dT FILE'
482 which specifies a replacement for the built in, default linker
483 script.
484
485 * ELF: Add -Bsymbolic-functions, --dynamic-list-cpp-new, which puts C++
486 operator new and delete on the dynamic list, and --dynamic-list-data,
487 builtin list for --dynamic-list, which puts global data symbols on the
488 dynamic list.
489
490 * Add support for x86_64 PE+ target.
491
492 * Add support for Score target.
493
494 * ELF: Add --dynamic-list option to specify a list of global symbols
495 whose references shouldn't be bound to the definition within the
496 shared library, or a list of symbols which should be added to the
497 symbol table in the executable.
498
499 * The default output section LMA has changed for allocatable sections from
500 being equal to VMA, to keeping the difference between LMA and VMA the same as
501 the previous output section in the same region. This is a more useful
502 default when using overlays and other cases where you specify an LMA
503 differing from the VMA for some sections.
504
505 * New switch: --print-gc-sections to list any sections removed by garabge
506 collection.
507
508 * ARM: Added --vfp11-denorm-fix option to work around an erratum in current
509 VFP11 coprocessors.
510
511 Changes in 2.17:
512
513 * Support for the Infineon XC16X has been added by KPIT Cummins Infosystems.
514
515 * Modify the Linux linker search order to better match ld.so search order.
516 Look for DT_NEEDED libraries in paths specified by ld.so.conf before
517 searching the default directories, rather than vice versa.
518 Use $prefix/etc/ld.so.conf if it exists, otherwise /etc/ld.so.conf.
519
520 * PE-COFF: Forward exports from DLL's can now be specified in .def files
521 passed directly to ld.
522
523 * Support for the Z80 processor family has been added.
524
525 * Add support for the "@<file>" syntax to the command line, so that extra
526 switches can be read from <file>.
527
528 Changes in 2.16:
529
530 * Support for the R_ARM_V4BX relocation as defined in the ARM AAELF
531 specification has been added via the --fix-v4bx command-line option.
532
533 * New linker script construct AS_NEEDED(), which sets the --as-needed flag
534 for input files listed inside of it.
535
536 * A new command-line option, --sysroot, can be used to override the
537 default sysroot location. It only applies to toolchains that were
538 configured using --with-sysroot.
539
540 * New linker script functions: ORIGIN() and LENGTH() which return information
541 about a specified memory region.
542
543 * Port to MAXQ processor contributed by HCL Tech.
544
545 * Added SEGMENT_START to the linker script language to permit the user to
546 override the base address for a segment from the command-line.
547
548 * ELF: --warn-shared-textrel option to warn if adding a DT_TEXTREL to a shared
549 object.
550
551 * Added SORT_BY_NAME and SORT_BY_ALIGNMENT to the linker script
552 language to permit sorting sections by section name or section
553 maximum alignment.
554
555 * Added a new linker command-line switch, --sort-section name|alignment,
556 to sort sections by section name or maximum alignment.
557
558 * ELF: --add-needed/--no-add-needed options to control if a DT_NEEDED tag
559 should be added when a shared library comes from DT_NEEDED tags.
560
561 * Support for the crx-elf target added.
562
563 * Support for the sh-symbianelf target added.
564
565 * A new linker command-line switch has been added which allows the hash table
566 size to be set to a suitable prime value near to its argument. This switch
567 is --hash-size=<NUMBER>. Also if the switch --reduce-memory-overheads is
568 used, and --hash-size has not been used, then the default value will be set
569 to 1021.
570
571 * Linker map files are now generated with an O(N) algorithm for finding symbols
572 that are defined in each section. This uses about 40% more memory for
573 symbols than the old O(N^2) algorithm. You can use the new
574 --reduce-memory-overheads option to select the old algorithm; this option
575 might also be used in the future to select similar tradeoffs.
576
577 Changes in 2.15:
578
579 * ELF: --as-needed/--no-as-needed options to control if a DT_NEEDED tag should
580 be added only when a shared library is referenced.
581
582 * PE: --large-address-aware option to indicate executables support virtual
583 addresses greater than 2 gigabytes.
584
585 * DWARF 2 support for i386pe added.
586
587 * The linker script operator DEFINED() will now yield 1 only for a symbol that
588 is defined before the statement where DEFINED is used.
589
590 * The MIPS --embedded-relocs (used to embed relocations into binaries for
591 Embedded-PIC code) is deprecated and will be removed in a future release.
592
593 * cr16c support added by NSC.
594
595 * m32r Linux (ELF) support added by Renesas.
596
597 * Improved linker's handling of unresolved symbols. The switch
598 --unresolved-symbols=<method> has been added to tell the linker when it
599 should report them and the switch --warn-unresolved-symbols has been added to
600 make reports be issued as warning messages rather than errors.
601
602 Changes in 2.14:
603
604 * Added support for Xtensa architecture.
605
606 * Added --with-sysroot configure switch to specify a target system root, for
607 linking against a target filesystem image.
608
609 * Added --accept-unknown-linker-format to restore old linker behaviour (pre
610 2.14) of silently accepting and linking in any files in an unknown binary
611 file format.
612
613 * Added --no-omagic to undo the effects of the -N option.
614
615 * Support for Texas Instruments TMS320C4x and TMS320C3x series of
616 DSP's contributed by Michael Hayes and Svein E. Seldal.
617
618 * Added --with-lib-path configure switch to specify default value for
619 LIB_PATH.
620
621 * ARM port to QNX operating system added by Graeme Peterson.
622
623 * IP2K support added by Denis Chertykov.
624
625 Changes in 2.13:
626
627 * Support for the Fujitsu FRV architecture added by Red Hat. Models for FR400
628 and FR500 included.
629
630 Changes in version 2.13:
631
632 * DEC VAX ELF support, by Matt Thomas.
633
634 Changes in version 2.12:
635
636 * Support for Don Knuth's MMIX, by Hans-Peter Nilsson.
637
638 * Support for the OpenRISC 32-bit embedded processor by OpenCores.
639
640 * Support for -z nocopyreloc in the x86 ELF linker, which disables
641 production of copy relocs. Warning: using this option may result in
642 non-sharable applications.
643
644 * Support for -z combreloc in the ELF linker, which puts dynamic
645 relocations against the same symbol together, so that dynamic linker
646 can use an one-entry symbol lookup cache.
647
648 * Support for ELF SHF_MERGE section merging, by Jakub Jelinek.
649
650 Changes in version 2.11:
651
652 * Support for AMD x86-64 architecture, by Jan Hubicka, SuSE Labs.
653
654 * Support added for eliminating duplicate DWARF2 debug information by
655 having the compiler generate the information in sections called
656 .gnu.linkonce.wi.XXXX where XXXX is a checksum for the contents. The
657 linker then merges these sections together into the normal .debug_info
658 section.
659
660 * The native ELF linker now searches the directories in DT_RUNPATH or
661 DT_RPATH of a shared library for shared libraries needed by it.
662
663 * TI C54x support, by Timothy Wall.
664
665 * Added command-line switch --section-start to set the start address of any
666 specified section.
667
668 * Added ability to emit full relocation information in linked executables,
669 enabled by --emit-relocs. Some post-linkage optimization tools need
670 this information in order to be able to correctly identify and perform
671 symbol relative addressing in the event of changes in section contents
672 (instructions being added or deleted, extending data sections, etc.)
673
674 * Support for i860, by Jason Eckhardt (preliminary, alpha quality).
675
676 * Support for CRIS (Axis Communications ETRAX series).
677
678 * Support for PDP-11 and 2.11BSD a.out format, by Lars Brinkhoff.
679
680 Changes in version 2.10:
681
682 * Added AT> to the linker script language to allow load-time allocation of
683 sections into regions.
684
685 * Added garbage collection of unused sections, enabled by --gc-sections.
686 It does require a bit of backend support; currently implemented are
687 arm-elf, avr-elf, d10v-elf, fr30-elf, i386-elf, m32r-elf, m68k-elf,
688 mcore-elf, mips-elf, mn10300-elf, ppc-elf, sh-elf, sparc-elf, and v850-elf.
689 Others will ignore the option.
690
691 * Added SORT to the linker script language to permit sorting sections by file
692 name or section name.
693
694 * Added EXTERN to the linker script language as an equivalent to the -u
695 command-line option.
696
697 * Added ASSERT to the linker script language.
698
699 * Added EXCLUDE_FILE to the linker script language for further control over
700 wildcard file names.
701
702 * Added -O option to optimize linker output (as of this writing, this only
703 affects ELF shared library generation).
704
705 * The -e option now accepts a number as well as a symbol name.
706
707 * Added --no-undefined option to disallow undefined symbols when creating a
708 shared library.
709
710 * The linker now issues a warning, not an error, for an undefined symbol when
711 using -Bsymbolic; use the new --no-undefined option to get the old
712 behaviour.
713
714 * Added --demangle and --no-demangle options.
715
716 Changes in version 2.9:
717
718 * Added SQUAD to the linker script language.
719
720 * New option --no-warn-mismatch.
721
722 * The MEMORY command now parses the attributes to determine where sections that
723 are not placed in a specific memory region are placed.
724
725 Changes in version 2.8:
726
727 * Linker scripts may now contain shell wildcard characters for file and section
728 names.
729
730 * The linker now supports symbol versions in ELF.
731
732 * The NOCROSSREFS command was added to the linker script language.
733
734 * The LOADADDR expression was added to the linker script language.
735
736 * MAX and MIN functions were added to the linker script language.
737
738 * The OVERLAY construct was added to the linker script language.
739
740 * New option --warn-section-align to warn when the address of an output section
741 changes due to alignment of an input section.
742
743 * New options --filter/-F and --auxiliary/-f.
744
745 Changes in version 2.7:
746
747 * New option --cref to print out a cross reference table.
748
749 * New option --wrap SYMBOL.
750
751 * New option --no-whole-archive, to turn off the effect of --whole-archive.
752
753 * Input sections assigned to the output section /DISCARD/ in the linker script
754 are not included in the output file.
755
756 * The SunOS and ELF linkers now merge stabs debugging information which uses
757 the N_BINCL and N_EINCL stab types. This reduces the amount of debugging
758 information generated.
759
760 Changes in version 2.6:
761
762 * When an ELF section name is representable as a C identifier (this is not true
763 of most ELF section names), the linker will automatically define symbols
764 __start_SECNAME and __stop_SECNAME, where SECNAME is the section name, at the
765 beginning and the end of the section. This is used by glibc.
766
767 Addendum: Current versions of the linker (at least for version 2.18 onwards
768 and possibly much earlier as well) place two restrictions on this feature: The
769 symbols are only implemented for orphaned sections, not for explicitly placed
770 sections and they are PROVIDEd rather than being defined.
771
772 * When an ELF section named .gnu.warning is encountered in an input file, the
773 contents of the section are displayed as an error message, and the section is
774 not copied into the output file. This is used by glibc.
775
776 * When an ELF section named .gnu.warning.SYMBOL is encountered in an input
777 file, and the symbol SYMBOL is referenced by some object file, the contents of
778 the section are displayed as an error message. The section is not copied into
779 the output file, unless doing a relocatable or shared link. This is used by
780 glibc.
781
782 * New options -split-by-reloc and -split-by-file.
783
784 * The linker now supports linking PIC compiled code on SPARC SunOS. It can
785 also create SPARC SunOS shared libraries, and, like the native SunOS linker,
786 will do so whenever there is an undefined symbol in the link and neither the -e
787 nor the -r option was used.
788
789 * The -rpath option may be used on SunOS to set the list of directories to be
790 searched at run time. This overrides the default of building the list from the
791 -L options.
792
793 * The COFF linker now combines debugging information for structs, unions, and
794 enums, so that even if the same type is defined in multiple input files it will
795 only be defined once in the output file. The --traditional-format switch will
796 prevent this optimization.
797
798 Changes in version 2.5:
799
800 * The linker now supports linking against SunOS shared libraries. It still can
801 not link SunOS PIC (Position Independent Code) files, so it can not be used to
802 generate shared libraries.
803
804 * The linker now supports linking against ELF shared libraries for the i386
805 (UnixWare) and SPARC (Solaris). It can also link ELF PIC files, and can be
806 used to generate shared libraries. Shared library generation is not well
807 tested; please report any problems encountered. The linker is now enabled for
808 Solaris again.
809
810 * Eric Youngdale has contributed Linux support code, including linking against
811 Linux a.out shared libraries. The linker produces Linux QMAGIC binaries.
812
813 * The ELF backend has been converted to the new linker code. To use the new
814 ELF linker, each particular target requires a relocation function. So far,
815 this function has been written for i386 (UnixWare), SPARC (Solaris) MIPS (Irix
816 5), and HPPA ELF targets.
817
818 * The -( (--start-group) and -) (--end-group) options have been added to
819 support searching a group of archives as though they were a single archive.
820 This can also be used in a linker script, as GROUP ( files ).
821
822 * When a file is named on the command line, and the linker does not recognize
823 it as an object file, the linker will now treat the file as a linker script
824 file. A linker script named in this way augments, but does not replace, the
825 default linker script.
826
827 * The -warn-once option was added. It causes the linker to only warn once per
828 undefined symbol, rather than once per reference.
829
830 * The COFF backend has been converted to the new linker code. As with ELF, to
831 use the new linker, each particular target requires a relocation function. So
832 far, this function has been written for the i386, m68k, a29k and SH targets.
833
834 * The -V flag was made a synonym for -v, for SVR4 compatibility. The old -V
835 behaviour is available via --verbose.
836
837 Changes in version 2.4:
838
839 * New linker code, by Steve Chamberlain and Ian Taylor. For a.out and ecoff
840 formats (so far), this should result in considerable savings in time
841 and memory used while linking; slightly poorer performance than
842 before for formats not converted yet.
843
844 * Command-line parsing is no longer done with flex. This means
845 oddball characters in filenames won't get treated as argument
846 separators.
847
848 * HP-PA ELF support, by Jeff Law. (No SOM support yet.)
849
850 * Mach i386 support, by David Mackenzie.
851
852 * Irix 4 shared libraries are now supported (Irix 5 uses ELF, and ELF shared
853 libraries are not yet supported).
854
855 * COFF shared libraries (as on SCO) should work as well.
856
857 * The linker is disabled for Solaris. (Actually, it was in 2.3 also, I just
858 forgot to note it.) Some of their C library routines don't work when
859 statically linked, and the GNU linker doesn't support dynamic linking yet.
860
861 Changes in version 2.3:
862
863 * Weak symbols are now supported.
864
865 * ELF support has been added. The linker has been bootstrapped on
866 UnixWare and Solaris.
867
868 * Alpha OSF/1 support has been added (non dynamic linking only).
869
870 Changes in version 2.2:
871
872 * The `bfd' library has been updated to reduce a.out-format string
873 table size. The effect of this is that files linked from many input
874 files with duplicate symbols (`-g' debugging records, or identical
875 static symbols) should be much smaller.
876
877 Changes in version 2.1:
878
879 * The ld -ySYMBOL flag (to trace references to SYMBOL) is now implemented.
880
881 * There is now support for writing ECOFF files, so ld and the
882 other utilities should work on Risc/Ultrix and Irix.
883
884 \f
885 Copyright (C) 2012-2022 Free Software Foundation, Inc.
886
887 Copying and distribution of this file, with or without modification,
888 are permitted in any medium without royalty provided the copyright
889 notice and this notice are preserved.
890
891 Local variables:
892 fill-column: 79
893 End: