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1 -*- text -*-
2
3 * Add a configure option, --enable-textrel-check=[no|yes|warning|error],
4 to decide what ELF linker should do by default with DT_TEXTREL in an
5 executable or shared library.
6
7 * The -Map=<filename> command line option has been extended so that if
8 <filename> is a directory then <filename>/<output-filename>.map will be
9 created.
10
11 * Add a command-line option for ELF linker, --warn-textrel, to warn that
12 DT_TEXTREL is set in a position-independent executable or shared object.
13
14 * Add command-line options --enable-non-contiguous-regions and
15 --enable-non-contiguous-regions-warnings.
16
17 * Add command-line option --imagic for the pdp11-aout target to output format
18 IMAGIC (0411) for separate instruction and data spaces, and change the
19 default format option for pdp11-aout to be --omagic.
20
21 * Relative pathnames in INPUT() and GROUP() directives in linker scripts are
22 searched relative to the directory of the linker script before other search
23 paths.
24
25 Changes in 2.34:
26
27 * The ld check for "PHDR segment not covered by LOAD segment" is more
28 effective, catching cases that were wrongly allowed by previous versions of
29 ld. If you see this error it is likely you are linking with a bad linker
30 script or the binary you are building is not intended to be loaded by a
31 dynamic loader. In the latter case --no-dynamic-linker is appropriate.
32
33 * cr16c support removed.
34
35 * Add support for z80-elf.
36
37 * Add support for relocation of each byte or word of multibyte value to Z80
38 targets.
39
40 * Add support for Zilog eZ80 (both ADL and Z80 mode) and Zilog Z180 CPUs.
41
42 Changes in 2.33:
43
44 * Add command-line option --no-print-map-discarded.
45
46 * The Cortex-A53 Erratum 843419 workaround now supports a choice of which
47 workaround to use. The option --fix-cortex-a53-843419 now takes an
48 optional argument --fix-cortex-a53-843419[=full|adr|adrp] which can be
49 used to force a particular workaround to be used. See --help for AArch64
50 for more details.
51
52 * Add target handlers for AArch64 for ELF GNU program properties.
53
54 * Add support for GNU_PROPERTY_AARCH64_FEATURE_1_BTI in ELF GNU program
55 properties in the AArch64 ELF linker.
56
57 * Add support for GNU_PROPERTY_AARCH64_FEATURE_1_PAC in ELF GNU program
58 properties in the AArch64 ELF linker.
59
60 * Add -z force-bti for AArch64 to enable GNU_PROPERTY_AARCH64_FEATURE_1_BTI
61 on output while warning about missing GNU_PROPERTY_AARCH64_FEATURE_1_BTI
62 on inputs and use PLTs protected with BTI.
63
64 * Add -z pac-plt for AArch64 to pick PAC enabled PLTs.
65
66 Changes in 2.32:
67
68 * Report property change in linker map file when merging GNU properties.
69
70 * Add support for the C-SKY processor series.
71
72 * -t now doesn't report members within archives, unless -t is given twice.
73 A single -t is now more useful when generating a list of files that should be
74 packaged for a linker bug report. For example:
75 gcc hello.c -save-temps -Wl,-t | xargs realpath | sort | uniq > files
76 tar cJf test.tar.xz `cat files`
77
78 Changes in 2.31:
79
80 * Speed up direct linking with DLLs for Cygwin and Mingw targets.
81
82 * Add a configure option --enable-separate-code to decide whether
83 -z separate-code should be enabled in ELF linker by default. Default
84 to yes for Linux/x86 targets. Note that -z separate-code can increase
85 disk and memory size.
86
87 Changes in 2.30:
88
89 * Add -z separate-code to generate separate code PT_LOAD segment.
90
91 * Add "-z undefs" command-line option as the inverse of the "-z defs" option.
92
93 * Add -z globalaudit command-line option to force audit libraries to be run
94 for every dynamic object loaded by an executable - provided that the loader
95 supports this functionality.
96
97 * Tighten linker script grammar around file name specifiers to prevent the use
98 of SORT_BY_ALIGNMENT and SORT_BY_INIT_PRIORITY on filenames. These would
99 previously be accepted but had no effect.
100
101 * The EXCLUDE_FILE directive can now be placed within any SORT_* directive
102 within input section lists.
103
104 Changes in 2.29:
105
106 * Support for -z shstk in the x86 ELF linker to generate
107 GNU_PROPERTY_X86_FEATURE_1_SHSTK in ELF GNU program properties.
108
109 * Add support for GNU_PROPERTY_X86_FEATURE_1_SHSTK in ELF GNU program
110 properties in the x86 ELF linker.
111
112 * Add support for GNU_PROPERTY_X86_FEATURE_1_IBT in ELF GNU program
113 properties in the x86 ELF linker.
114
115 * Support for -z ibtplt in the x86 ELF linker to generate IBT-enabled
116 PLT.
117
118 * Support for -z ibt in the x86 ELF linker to generate IBT-enabled
119 PLT as well as GNU_PROPERTY_X86_FEATURE_1_IBT in ELF GNU program
120 properties.
121
122 * Add support for ELF SHF_GNU_MBIND and PT_GNU_MBIND_XXX.
123
124 * Add support for ELF GNU program properties.
125
126 * Add support for the Texas Instruments PRU processor.
127
128 * When configuring for arc*-*-linux* targets the default linker emulation will
129 change if --with-cpu=nps400 is used at configure time.
130
131 * Improve assignment of LMAs to orphan sections in some edge cases where a
132 mixture of both AT>LMA_REGION and AT(LMA) are used.
133
134 * Orphan sections placed after an empty section that has an AT(LMA) will now
135 take an load memory address starting from LMA.
136
137 * Section groups can now be resolved (the group deleted and the group members
138 placed like normal sections) at partial link time either using the new linker
139 option --force-group-allocation or by placing FORCE_GROUP_ALLOCATION into the
140 linker script.
141
142 Changes in 2.28:
143
144 * The EXCLUDE_FILE linker script construct can now be applied outside of the
145 section list in order for the exclusions to apply over all input sections in
146 the list.
147
148 * Add support for the RISC-V architecture.
149
150 * The command-line option --no-eh-frame-hdr can now be used in ELF based
151 linkers to disable the automatic generation of .eh_frame_hdr sections.
152
153 * Add --in-implib=<infile> to the ARM linker to enable specifying a set of
154 Secure Gateway veneers that must exist in the output import library specified
155 by --out-implib=<outfile> and the address they must have. As such,
156 --in-implib is only supported in combination with --cmse-implib.
157
158 * Extended the --out-implib=<file> option, previously restricted to x86 PE
159 targets, to any ELF based target. This allows the generation of an import
160 library for an ELF executable, which can then be used by another application
161 to link against the executable.
162
163 Changes in 2.27:
164
165 * Add a configure option --enable-relro to decide whether -z relro should
166 be enabled in ELF linker by default. Default to yes for all Linux
167 targets except FRV, HPPA, IA64 and MIPS. Note that -z relro can increase
168 disk and memory size.
169
170 * Support for -z noreloc-overflow in the x86-64 ELF linker to disable
171 relocation overflow check.
172
173 * Add -z common/-z nocommon options for ELF targets to control whether to
174 convert common symbols to the STT_COMMON type during a relocatable link.
175
176 * Support for -z nodynamic-undefined-weak in the x86 ELF linker, which
177 avoids dynamic relocations against undefined weak symbols in executable.
178
179 * The NOCROSSREFSTO command was added to the linker script language.
180
181 * Add --no-apply-dynamic-relocs to the AArch64 linker to do not apply link-time
182 values for dynamic relocations.
183
184 Changes in 2.26:
185
186 * Add --fix-stm32l4xx-629360 to the ARM linker to enable a link-time
187 workaround for a bug in the bus matrix / memory controller for some of
188 the STM32 Cortex-M4 based products (STM32L4xx)
189
190 * Add a configure option --enable-compressed-debug-sections={all,ld} to
191 decide whether DWARF debug sections should be compressed by default.
192
193 * Add support for the ARC EM/HS, and ARC600/700 architectures.
194
195 * Experimental support for linker garbage collection (--gc-sections)
196 has been enabled for COFF and PE based targets.
197
198 * New command-line option for ELF targets to compress DWARF debug
199 sections, --compress-debug-sections=[none|zlib|zlib-gnu|zlib-gabi].
200
201 * New command-line option, --orphan-handling=[place|warn|error|discard], to
202 adjust how orphan sections are handled. The default is 'place' which gives
203 the current behaviour, 'warn' and 'error' issue a warning or error
204 respectively when orphan sections are found, and 'discard' will discard all
205 orphan sections.
206
207 * Add support for LLVM plugin.
208
209 * Add --print-memory-usage option to report memory blocks usage.
210
211 * Add --require-defined option, it's like --undefined except the new symbol
212 must be defined by the end of the link.
213
214 Changes in 2.25:
215
216 * PE binaries now once again contain real timestamps by default. To disable
217 the inclusion of a timestamp in a PE binary, use the --no-insert-timestamp
218 command-line option.
219
220 * Replace support for openrisc and or32 with support for or1k.
221
222 * Add support for the --build-id command-line option to COFF based targets.
223
224 * x86/x86_64 pe-coff now supports the --build-id option.
225
226 * Add support for the Andes NDS32.
227
228 Changes in 2.24:
229
230 * Add LOG2CEIL() builtin function to the linker script language
231
232 * Add support for the Texas Instruments MSP430X processor.
233
234 * Add support for Altera Nios II.
235
236 * Add support for the V850E3V5 architecture.
237
238 * Add support for the Imagination Technologies Meta processor.
239
240 * --enable-new-dtags no longer generates old dtags in addition to new dtags.
241
242 * Remove linker support for MIPS ECOFF targets.
243
244 * Add ALIGN_WITH_INPUT to the linker script language to force the alignment of
245 an output section to use the maximum alignment of all its input sections.
246
247 Changes in 2.23:
248
249 * Enable compressed debug section feature for x86/x86_64 pe-coff.
250
251 * Add support for the 64-bit ARM architecture: AArch64.
252
253 * Added SORT_NONE to the linker script language to disable section sorting.
254
255 * Add a linker-provided symbol when producing ELF output, '__ehdr_start'
256 to point to the ELF file header (and nearby program headers) in the
257 program's memory image.
258
259 * Add support for S12X processor.
260
261 * Add support for the VLE extension to the PowerPC architecture.
262
263 * Add support for the Freescale XGATE architecture.
264
265 * Add option -f FILE on AIX (for response file).
266
267 * Add support for the Renesas RL78 architecture.
268
269 * Add support for the Adapteva EPIPHANY architecture.
270
271 Changes in 2.22:
272
273 * --copy-dt-needed-entries is no longer enabled by default. Instead
274 --no-copy-dt-needed-entries is the default.
275
276 * INPUT_SECTION_FLAGS has been added to the linker script language
277 to allow selection of input sections by section header section flags.
278
279 * Add support for the Tilera TILEPro and TILE-Gx architectures.
280
281 * Added SORT_BY_INIT_PRIORITY to the linker script language to permit
282 sorting sections by numerical value of the GCC init_priority attribute
283 encoded in the section name.
284
285 Changes in 2.21:
286
287 * Linker script expression evaluation is somewhat more sane. This may
288 break scripts that depend on quirks of the old expression evaluation.
289
290 * Turn off underscoring for x86_64 PE+-COFF targets. For old behavior the
291 option --enable-leading-mingw64-underscores can be used on configure of
292 bfd.
293
294 * Add support for the TMS320C6000 (TI C6X) processor family.
295
296 * --add-needed renamed to --copy-dt-needed-entries in order to avoid confusion
297 with --as-needed option.
298
299 * Extend .def file syntax by '== <ID>' for imports and exports. This allows
300 to alias the import/export table name written in PE image.
301
302 * Add --exclude-all-symbols option to PE based linkers. This prevents all
303 symbols from automatically being exported.
304
305 * Add support for the Renesas RX processor.
306
307 * Add support for alpha-vms target.
308
309 Changes in 2.20:
310
311 * GNU/Linux targets now support the STB_GNU_UNIQUE symbol binding. This is a
312 GNU extension to the standard set of ELF symbol bindings. The binding will
313 be passed on to the dynamic linker which will make sure that in the entire
314 process there is just one symbol with the given name and type in use.
315
316 * PE targets now support a GNU extension to allow the alignment of common
317 common symbols to be specified. This support uses custom options in
318 the .drectve section, which will be disregarded by the native tools.
319
320 * PE targets now add primitive support for ELF version scripts; symbols
321 are not versioned, but the local and global symbol visibility directives
322 are respected when filtering symbols in auto-export mode.
323
324 * New option --no-export-dynamic to undo the effect of the -E and
325 --export-dynamic options.
326
327 * ELF: --warn-alternate-em option to warn if an object has alternate
328 ELF machine code.
329
330 * New script function REGION_ALIAS to add alias names to memory regions.
331
332 * PE targets no longer make use of the long section names PE extension to
333 the COFF format when generating executable images, by default. The old
334 (slightly non-conformant) behaviour can still be invoked by using the
335 new '--enable-long-section-names' command-line option. It is also enabled
336 automatically in the presence of un-stripped debug information, as GDB
337 needs to be able to find the debug info sections by their full names.
338
339 * For GNU/Linux systems the linker will now avoid processing any relocations
340 made against symbols of the STT_GNU_IFUNC type and instead emit them into
341 the resulting binary for processing by the loader.
342
343 * --as-needed now links in a dynamic library if it satisfies undefined
344 symbols in regular objects, or in other dynamic libraries. In the
345 latter case the library is not linked if it is found in a DT_NEEDED
346 entry of one of the libraries already linked.
347
348 * Add a new command-line option, -Ttext-segment ADDR, for ELF targets
349 to set the address of the first byte of the text segment.
350
351 * Add support for Sunplus score architecture.
352
353 * Add new option --use-nul-prefixed-import-tables to ld for PE targets to
354 allow fallback to old import table generation with null element prefix.
355
356 * Windows PE systems now support a new --exclude-modules-for-implib option,
357 allowing users to partition object files and archive members between a DLL
358 and its associated import library as they are generated during linking.
359
360 * Add support for Lattice Mico32 (lm32) architecture.
361
362 * Add CR16 ELF --embedded-relocs (used to embedded relocations into binaries
363 for Embedded-PIC code) option.
364
365 * Add to the PE/PE+ targets the support of two different kinds of
366 pseudo-relocations. They can be selected by the switches
367 --enable-runtime-pseudo-reloc-v1 and --enable-runtime-pseudo-reloc-v2.
368 For the switch --enable-runtime-pseudo-reloc it uses for 32-bit
369 runtime pseudo relocation version one, for 64-bit the version two.
370
371 Changes in 2.19:
372
373 * Linker scripts support a new INSERT command that makes it easier to
374 augment the default script.
375
376 * Linker script input section filespecs may now specify a file within an
377 archive by writing "archive:file".
378
379 * The --sort-common switch now has an optional argument which specifies the
380 direction of sorting.
381
382 * The M68K linker now supports multiple GOT generation schemes controlled via
383 the --got=<type> command-line option.
384
385 * The ARM EABI linker will now generate stubs for function calls to symbols
386 that are too far away. The placement of the stubs is controlled by a new
387 linker command-line option: --stub-group-size=N.
388
389 Changes in 2.18:
390
391 * Linker sources now released under version 3 of the GNU General Public
392 License.
393
394 * ELF: New --build-id option to generate a unique per-binary identifier
395 embedded in a note section.
396
397 * Added support for National Semicondutor CompactRISC (ie CR16) target.
398
399 * -l:foo now searches the library path for a filename called foo,
400 without converting it to libfoo.a or libfoo.so.
401
402 * Add a new command-line option '--default-script=FILE' or '-dT FILE'
403 which specifies a replacement for the built in, default linker
404 script.
405
406 * ELF: Add -Bsymbolic-functions, --dynamic-list-cpp-new, which puts C++
407 operator new and delete on the dynamic list, and --dynamic-list-data,
408 builtin list for --dynamic-list, which puts global data symbols on the
409 dynamic list.
410
411 * Add support for x86_64 PE+ target.
412
413 * Add support for Score target.
414
415 * ELF: Add --dynamic-list option to specify a list of global symbols
416 whose references shouldn't be bound to the definition within the
417 shared library, or a list of symbols which should be added to the
418 symbol table in the executable.
419
420 * The default output section LMA has changed for allocatable sections from
421 being equal to VMA, to keeping the difference between LMA and VMA the same as
422 the previous output section in the same region. This is a more useful
423 default when using overlays and other cases where you specify an LMA
424 differing from the VMA for some sections.
425
426 * New switch: --print-gc-sections to list any sections removed by garabge
427 collection.
428
429 * ARM: Added --vfp11-denorm-fix option to work around an erratum in current
430 VFP11 coprocessors.
431
432 Changes in 2.17:
433
434 * Support for the Infineon XC16X has been added by KPIT Cummins Infosystems.
435
436 * Modify the Linux linker search order to better match ld.so search order.
437 Look for DT_NEEDED libraries in paths specified by ld.so.conf before
438 searching the default directories, rather than vice versa.
439 Use $prefix/etc/ld.so.conf if it exists, otherwise /etc/ld.so.conf.
440
441 * PE-COFF: Forward exports from DLL's can now be specified in .def files
442 passed directly to ld.
443
444 * Support for the Z80 processor family has been added.
445
446 * Add support for the "@<file>" syntax to the command line, so that extra
447 switches can be read from <file>.
448
449 Changes in 2.16:
450
451 * Support for the R_ARM_V4BX relocation as defined in the ARM AAELF
452 specification has been added via the --fix-v4bx command-line option.
453
454 * New linker script construct AS_NEEDED(), which sets the --as-needed flag
455 for input files listed inside of it.
456
457 * A new command-line option, --sysroot, can be used to override the
458 default sysroot location. It only applies to toolchains that were
459 configured using --with-sysroot.
460
461 * New linker script functions: ORIGIN() and LENGTH() which return information
462 about a specified memory region.
463
464 * Port to MAXQ processor contributed by HCL Tech.
465
466 * Added SEGMENT_START to the linker script language to permit the user to
467 override the base address for a segment from the command-line.
468
469 * ELF: --warn-shared-textrel option to warn if adding a DT_TEXTREL to a shared
470 object.
471
472 * Added SORT_BY_NAME and SORT_BY_ALIGNMENT to the linker script
473 language to permit sorting sections by section name or section
474 maximum alignment.
475
476 * Added a new linker command-line switch, --sort-section name|alignment,
477 to sort sections by section name or maximum alignment.
478
479 * ELF: --add-needed/--no-add-needed options to control if a DT_NEEDED tag
480 should be added when a shared library comes from DT_NEEDED tags.
481
482 * Support for the crx-elf target added.
483
484 * Support for the sh-symbianelf target added.
485
486 * A new linker command-line switch has been added which allows the hash table
487 size to be set to a suitable prime value near to its argument. This switch
488 is --hash-size=<NUMBER>. Also if the switch --reduce-memory-overheads is
489 used, and --hash-size has not been used, then the default value will be set
490 to 1021.
491
492 * Linker map files are now generated with an O(N) algorithm for finding symbols
493 that are defined in each section. This uses about 40% more memory for
494 symbols than the old O(N^2) algorithm. You can use the new
495 --reduce-memory-overheads option to select the old algorithm; this option
496 might also be used in the future to select similar tradeoffs.
497
498 Changes in 2.15:
499
500 * ELF: --as-needed/--no-as-needed options to control if a DT_NEEDED tag should
501 be added only when a shared library is referenced.
502
503 * PE: --large-address-aware option to indicate executables support virtual
504 addresses greater than 2 gigabytes.
505
506 * DWARF 2 support for i386pe added.
507
508 * The linker script operator DEFINED() will now yield 1 only for a symbol that
509 is defined before the statement where DEFINED is used.
510
511 * The MIPS --embedded-relocs (used to embed relocations into binaries for
512 Embedded-PIC code) is deprecated and will be removed in a future release.
513
514 * cr16c support added by NSC.
515
516 * m32r Linux (ELF) support added by Renesas.
517
518 * Improved linker's handling of unresolved symbols. The switch
519 --unresolved-symbols=<method> has been added to tell the linker when it
520 should report them and the switch --warn-unresolved-symbols has been added to
521 make reports be issued as warning messages rather than errors.
522
523 Changes in 2.14:
524
525 * Added support for Xtensa architecture.
526
527 * Added --with-sysroot configure switch to specify a target system root, for
528 linking against a target filesystem image.
529
530 * Added --accept-unknown-linker-format to restore old linker behaviour (pre
531 2.14) of silently accepting and linking in any files in an unknown binary
532 file format.
533
534 * Added --no-omagic to undo the effects of the -N option.
535
536 * Support for Texas Instruments TMS320C4x and TMS320C3x series of
537 DSP's contributed by Michael Hayes and Svein E. Seldal.
538
539 * Added --with-lib-path configure switch to specify default value for
540 LIB_PATH.
541
542 * ARM port to QNX operating system added by Graeme Peterson.
543
544 * IP2K support added by Denis Chertykov.
545
546 Changes in 2.13:
547
548 * Support for the Fujitsu FRV architecture added by Red Hat. Models for FR400
549 and FR500 included.
550
551 Changes in version 2.13:
552
553 * DEC VAX ELF support, by Matt Thomas.
554
555 Changes in version 2.12:
556
557 * Support for Don Knuth's MMIX, by Hans-Peter Nilsson.
558
559 * Support for the OpenRISC 32-bit embedded processor by OpenCores.
560
561 * Support for -z nocopyreloc in the x86 ELF linker, which disables
562 production of copy relocs. Warning: using this option may result in
563 non-sharable applications.
564
565 * Support for -z combreloc in the ELF linker, which puts dynamic
566 relocations against the same symbol together, so that dynamic linker
567 can use an one-entry symbol lookup cache.
568
569 * Support for ELF SHF_MERGE section merging, by Jakub Jelinek.
570
571 Changes in version 2.11:
572
573 * Support for AMD x86-64 architecture, by Jan Hubicka, SuSE Labs.
574
575 * Support added for eliminating duplicate DWARF2 debug information by
576 having the compiler generate the information in sections called
577 .gnu.linkonce.wi.XXXX where XXXX is a checksum for the contents. The
578 linker then merges these sections together into the normal .debug_info
579 section.
580
581 * The native ELF linker now searches the directories in DT_RUNPATH or
582 DT_RPATH of a shared library for shared libraries needed by it.
583
584 * TI C54x support, by Timothy Wall.
585
586 * Added command-line switch --section-start to set the start address of any
587 specified section.
588
589 * Added ability to emit full relocation information in linked executables,
590 enabled by --emit-relocs. Some post-linkage optimization tools need
591 this information in order to be able to correctly identify and perform
592 symbol relative addressing in the event of changes in section contents
593 (instructions being added or deleted, extending data sections, etc.)
594
595 * Support for i860, by Jason Eckhardt (preliminary, alpha quality).
596
597 * Support for CRIS (Axis Communications ETRAX series).
598
599 * Support for PDP-11 and 2.11BSD a.out format, by Lars Brinkhoff.
600
601 Changes in version 2.10:
602
603 * Added AT> to the linker script language to allow load-time allocation of
604 sections into regions.
605
606 * Added garbage collection of unused sections, enabled by --gc-sections.
607 It does require a bit of backend support; currently implemented are
608 arm-elf, avr-elf, d10v-elf, fr30-elf, i386-elf, m32r-elf, m68k-elf,
609 mcore-elf, mips-elf, mn10300-elf, ppc-elf, sh-elf, sparc-elf, and v850-elf.
610 Others will ignore the option.
611
612 * Added SORT to the linker script language to permit sorting sections by file
613 name or section name.
614
615 * Added EXTERN to the linker script language as an equivalent to the -u
616 command-line option.
617
618 * Added ASSERT to the linker script language.
619
620 * Added EXCLUDE_FILE to the linker script language for further control over
621 wildcard file names.
622
623 * Added -O option to optimize linker output (as of this writing, this only
624 affects ELF shared library generation).
625
626 * The -e option now accepts a number as well as a symbol name.
627
628 * Added --no-undefined option to disallow undefined symbols when creating a
629 shared library.
630
631 * The linker now issues a warning, not an error, for an undefined symbol when
632 using -Bsymbolic; use the new --no-undefined option to get the old
633 behaviour.
634
635 * Added --demangle and --no-demangle options.
636
637 Changes in version 2.9:
638
639 * Added SQUAD to the linker script language.
640
641 * New option --no-warn-mismatch.
642
643 * The MEMORY command now parses the attributes to determine where sections that
644 are not placed in a specific memory region are placed.
645
646 Changes in version 2.8:
647
648 * Linker scripts may now contain shell wildcard characters for file and section
649 names.
650
651 * The linker now supports symbol versions in ELF.
652
653 * The NOCROSSREFS command was added to the linker script language.
654
655 * The LOADADDR expression was added to the linker script language.
656
657 * MAX and MIN functions were added to the linker script language.
658
659 * The OVERLAY construct was added to the linker script language.
660
661 * New option --warn-section-align to warn when the address of an output section
662 changes due to alignment of an input section.
663
664 * New options --filter/-F and --auxiliary/-f.
665
666 Changes in version 2.7:
667
668 * New option --cref to print out a cross reference table.
669
670 * New option --wrap SYMBOL.
671
672 * New option --no-whole-archive, to turn off the effect of --whole-archive.
673
674 * Input sections assigned to the output section /DISCARD/ in the linker script
675 are not included in the output file.
676
677 * The SunOS and ELF linkers now merge stabs debugging information which uses
678 the N_BINCL and N_EINCL stab types. This reduces the amount of debugging
679 information generated.
680
681 Changes in version 2.6:
682
683 * When an ELF section name is representable as a C identifier (this is not true
684 of most ELF section names), the linker will automatically define symbols
685 __start_SECNAME and __stop_SECNAME, where SECNAME is the section name, at the
686 beginning and the end of the section. This is used by glibc.
687
688 Addendum: Current versions of the linker (at least for version 2.18 onwards
689 and possibly much earlier as well) place two restrictions on this feature: The
690 symbols are only implemented for orphaned sections, not for explicitly placed
691 sections and they are PROVIDEd rather than being defined.
692
693 * When an ELF section named .gnu.warning is encountered in an input file, the
694 contents of the section are displayed as an error message, and the section is
695 not copied into the output file. This is used by glibc.
696
697 * When an ELF section named .gnu.warning.SYMBOL is encountered in an input
698 file, and the symbol SYMBOL is referenced by some object file, the contents of
699 the section are displayed as an error message. The section is not copied into
700 the output file, unless doing a relocatable or shared link. This is used by
701 glibc.
702
703 * New options -split-by-reloc and -split-by-file.
704
705 * The linker now supports linking PIC compiled code on SPARC SunOS. It can
706 also create SPARC SunOS shared libraries, and, like the native SunOS linker,
707 will do so whenever there is an undefined symbol in the link and neither the -e
708 nor the -r option was used.
709
710 * The -rpath option may be used on SunOS to set the list of directories to be
711 searched at run time. This overrides the default of building the list from the
712 -L options.
713
714 * The COFF linker now combines debugging information for structs, unions, and
715 enums, so that even if the same type is defined in multiple input files it will
716 only be defined once in the output file. The --traditional-format switch will
717 prevent this optimization.
718
719 Changes in version 2.5:
720
721 * The linker now supports linking against SunOS shared libraries. It still can
722 not link SunOS PIC (Position Independent Code) files, so it can not be used to
723 generate shared libraries.
724
725 * The linker now supports linking against ELF shared libraries for the i386
726 (UnixWare) and SPARC (Solaris). It can also link ELF PIC files, and can be
727 used to generate shared libraries. Shared library generation is not well
728 tested; please report any problems encountered. The linker is now enabled for
729 Solaris again.
730
731 * Eric Youngdale has contributed Linux support code, including linking against
732 Linux a.out shared libraries. The linker produces Linux QMAGIC binaries.
733
734 * The ELF backend has been converted to the new linker code. To use the new
735 ELF linker, each particular target requires a relocation function. So far,
736 this function has been written for i386 (UnixWare), SPARC (Solaris) MIPS (Irix
737 5), and HPPA ELF targets.
738
739 * The -( (--start-group) and -) (--end-group) options have been added to
740 support searching a group of archives as though they were a single archive.
741 This can also be used in a linker script, as GROUP ( files ).
742
743 * When a file is named on the command line, and the linker does not recognize
744 it as an object file, the linker will now treat the file as a linker script
745 file. A linker script named in this way augments, but does not replace, the
746 default linker script.
747
748 * The -warn-once option was added. It causes the linker to only warn once per
749 undefined symbol, rather than once per reference.
750
751 * The COFF backend has been converted to the new linker code. As with ELF, to
752 use the new linker, each particular target requires a relocation function. So
753 far, this function has been written for the i386, m68k, a29k and SH targets.
754
755 * The -V flag was made a synonym for -v, for SVR4 compatibility. The old -V
756 behaviour is available via --verbose.
757
758 Changes in version 2.4:
759
760 * New linker code, by Steve Chamberlain and Ian Taylor. For a.out and ecoff
761 formats (so far), this should result in considerable savings in time
762 and memory used while linking; slightly poorer performance than
763 before for formats not converted yet.
764
765 * Command-line parsing is no longer done with flex. This means
766 oddball characters in filenames won't get treated as argument
767 separators.
768
769 * HP-PA ELF support, by Jeff Law. (No SOM support yet.)
770
771 * Mach i386 support, by David Mackenzie.
772
773 * Irix 4 shared libraries are now supported (Irix 5 uses ELF, and ELF shared
774 libraries are not yet supported).
775
776 * COFF shared libraries (as on SCO) should work as well.
777
778 * The linker is disabled for Solaris. (Actually, it was in 2.3 also, I just
779 forgot to note it.) Some of their C library routines don't work when
780 statically linked, and the GNU linker doesn't support dynamic linking yet.
781
782 Changes in version 2.3:
783
784 * Weak symbols are now supported.
785
786 * ELF support has been added. The linker has been bootstrapped on
787 UnixWare and Solaris.
788
789 * Alpha OSF/1 support has been added (non dynamic linking only).
790
791 Changes in version 2.2:
792
793 * The `bfd' library has been updated to reduce a.out-format string
794 table size. The effect of this is that files linked from many input
795 files with duplicate symbols (`-g' debugging records, or identical
796 static symbols) should be much smaller.
797
798 Changes in version 2.1:
799
800 * The ld -ySYMBOL flag (to trace references to SYMBOL) is now implemented.
801
802 * There is now support for writing ECOFF files, so ld and the
803 other utilities should work on Risc/Ultrix and Irix.
804
805 \f
806 Copyright (C) 2012-2020 Free Software Foundation, Inc.
807
808 Copying and distribution of this file, with or without modification,
809 are permitted in any medium without royalty provided the copyright
810 notice and this notice are preserved.
811
812 Local variables:
813 fill-column: 79
814 End: