3 * Add --section-ordering-file <FILE> option to add extra mapping of input
4 sections to output sections.
6 * Add -plugin-save-temps to store plugin intermediate files permanently.
10 * Add -z mark-plt/-z nomark-plt options to x86-64 ELF linker to mark PLT
11 entries with DT_X86_64_PLT, DT_X86_64_PLTSZ and DT_X86_64_PLTENT dynamic
12 tags. Also added --enable-mark-plt configure option to mark PLT entries
15 * Support Intel APX relocations.
17 * On RISC-V, add ld target option --[no-]check-uleb128. Should rebuild the
18 objects by binutils 2.42 and up if enabling the option and get warnings,
19 since the non-zero addend of SUB_ULEB128 shouldn't be generated from .uleb128
22 * Add support for the KVX instruction set.
24 * A new linker script sorting directive has been added: REVERSE. This reverses
25 the order of the sorting. It may be combined with either SORT_BY_NAME or
26 SORT_BY_INIT_PRIORITY.
28 * Added --warn-execstack-objects to warn about executable stacks only when an
29 input object file requests one. Also added --error-execstack and
30 --error-rxw-segments options to convert warnings about executable stacks and
33 Also added --enable-error-execstack=[yes|no] and
34 --enable-error-rwx-segments=[yes|no] configure options to set the default for
35 converting warnings into errors.
37 * On LoongArch, various linker relaxation bugs are fixed; the most notable
38 of which is BZ 30944 (incorrect .balign semantics).
40 * On LoongArch, the LoongArch ABI v2.30 (LoongArch ELF psABI v20231219) is
41 now implemented. This includes new relocation types, and changed
42 semantics for PC-relative relocations handling the higher half of 64-bit
45 * On LoongArch, link-time TLS optimization and TLS relaxation are now
50 * The linker now accepts a command line option of --remap-inputs
51 <PATTERN>=<FILE> to relace any input file that matches <PATTERN> with
52 <FILE>. In addition the option --remap-inputs-file=<FILE> can be used to
53 specify a file containing any number of these remapping directives.
55 * The linker command line option --print-map-locals can be used to include
56 local symbols in a linker map. (ELF targets only).
58 * For most ELF based targets, if the --enable-linker-version option is used
59 then the version of the linker will be inserted as a string into the .comment
62 * The linker script syntax has a new command for output sections: ASCIZ "string"
63 This will insert a zero-terminated string at the current location.
65 * Add command-line option, -z nosectionheader, to omit ELF section
70 * The linker has a new command line option to suppress the generation of any
71 warning or error messages. This can be useful when there is a need to create
72 a known non-working binary. The option is -w or --no-warnings.
74 * ld now supports zstd compressed debug sections. The new option
75 --compress-debug-sections=zstd compresses debug sections with zstd.
77 * Add --enable-default-compressed-debug-sections-algorithm={zlib,zstd}
78 that selects the default compression algorithm
79 for --enable-compressed-debug-sections.
81 * Remove support for -z bndplt (MPX prefix instructions).
85 * The ELF linker will now generate a warning message if the stack is made
86 executable. By default this warning is not issued if the user has
87 specifically requested an executable stack via the "-z execstack"
88 command line option, but the warning can be forced via the new
89 "--warn-execstack" option. Alternatively all warnings about creating
90 an executable stack can be suppressed via the "--no-warn-execstack"
93 In addition the ELF linker will also warn if it creates a memory resident
94 segment with all three of the Read, Write and eXecute permissions set, or
95 if it creates a thread local data segment with the eXecute permission set.
96 These warnings can be disabled via --no-warn-rwx-segments option and
97 re-enabled via the --warn-rwx-segments option.
99 New configure options can also control these new features:
101 --enable-warn-execstack=no
102 will disable the warnings about creating an executable stack.
104 --enable-warn-execstack=yes
105 will make --warn-execstack enabled by default.
107 --enable-warn-rwx-segments=no
108 will make --no-warn-rwx-segments enabled by default.
110 --enable-default-execstack=no
111 will stop the creation of an executable stack simply because an input file
112 is missing a .note.GNU-stack section, even on architectures where this
113 behaviour is the default.
115 * TYPE=<type> is now supported in an output section description to set the
118 * Remove (rudimentary) support for the x86-64 sub-architectures Intel L1OM and
121 * The ELF linker now supports a new --package-metadata option that allows
122 embedding a JSON payload in accordance to the Package Metadata specification.
123 If support for libjansson is enabled at build time, the linker will use it to
124 validate the input. This can be enabled with --enable-jansson.
125 For more details, see: https://systemd.io/ELF_PACKAGE_METADATA/
129 * Add -z pack-relative-relocs/-z no pack-relative-relocs to x86 ELF
130 linker to pack relative relocations in the DT_RELR section.
132 * Add support for the LoongArch architecture.
134 * Add -z indirect-extern-access/-z noindirect-extern-access to x86 ELF
135 linker to control canonical function pointers and copy relocation.
137 * Add --max-cache-size=SIZE to set the the maximum cache size to SIZE
142 * arm-symbianelf support removed.
144 * Add -z report-relative-reloc to x86 ELF linker to report dynamic
145 relative relocations.
147 * Add -z start-stop-gc to disable special treatment of __start_*/__stop_*
148 references when --gc-sections.
150 * Add -Bno-symbolic to cancel -Bsymbolic and -Bsymbolic-functions.
154 * Add libdep plugin, for linking dependencies of static libraries that
155 were recorded by ar in the __.LIBDEP archive member.
157 * Add --error-handling-script=<NAME> command line option to allow a helper
158 script to be invoked when an undefined symbol or a missing library is
159 encountered. This option can be suppressed via the configure time
160 switch: --enable-error-handling-script=no.
162 * Add -z lam-u48 to x86-64 ELF linker to generate LAM_U48 property.
164 * Add -z lam-u57 to x86-64 ELF linker to enerate LAM_U57 property.
166 * Add -z lam-u48-report=[none|warning|error] to report missing LAM_U48
169 * Add -z lam-u57-report=[none|warning|error] to report missing LAM_U57
172 * Add -z lam-report=[none|warning|error] to report missing LAM_U48 and
175 * Add -z x86-64-{baseline|v[234]} to the x86 ELF linker to mark
176 x86-64-{baseline|v[234]} ISA level as needed.
178 * Add -z unique-symbol to avoid duplicated local symbol names.
180 * The creation of PE format DLLs now defaults to using a more secure set of DLL
183 * The linker now deduplicates the types in .ctf sections. The new
184 command-line option --ctf-share-types describes how to do this:
185 its default value, share-unconflicted, produces the most compact
188 * The linker now omits the "variable section" from .ctf sections by
189 default, saving space. This is almost certainly what you want
190 unless you are working on a project that has its own analogue
191 of symbol tables that are not reflected in the ELF symtabs.
193 * Add support for the SHF_GNU_RETAIN ELF section flag.
194 This flag specifies that the section should not be garbage collected by the
199 * X86 NaCl target support is removed.
201 * Add ELF linker command-line options, --export-dynamic-symbol and
202 --export-dynamic-symbol-list, to make symbols dynamic.
204 * Add a configure option, --enable-textrel-check=[no|yes|warning|error],
205 to decide what ELF linker should do by default with DT_TEXTREL in an
206 executable or shared library. Default to yes for Linux/x86 targets.
208 * The -Map=<filename> command line option has been extended so that if
209 <filename> is a directory then <filename>/<output-filename>.map will be
212 * Add a command-line option for ELF linker, --warn-textrel, to warn that
213 DT_TEXTREL is set in a position-independent executable or shared object.
215 * Add command-line options --enable-non-contiguous-regions and
216 --enable-non-contiguous-regions-warnings.
218 * Add command-line option --imagic for the pdp11-aout target to output format
219 IMAGIC (0411) for separate instruction and data spaces, and change the
220 default format option for pdp11-aout to be --omagic.
222 * Relative pathnames in INPUT() and GROUP() directives in linker scripts are
223 searched relative to the directory of the linker script before other search
226 * Add ELF linker command-line option `-z start-stop-visibility=...' to control
227 the visibility of synthetic `__start_SECNAME` and `__stop_SECNAME` symbols.
229 * Add command-line option --dependency-file to write a Make-style dependency
230 file listing the input files consulted by the linker, like the files written
231 by the compiler's -M -MP options.
235 * The ld check for "PHDR segment not covered by LOAD segment" is more
236 effective, catching cases that were wrongly allowed by previous versions of
237 ld. If you see this error it is likely you are linking with a bad linker
238 script or the binary you are building is not intended to be loaded by a
239 dynamic loader. In the latter case --no-dynamic-linker is appropriate.
241 * cr16c support removed.
243 * Add support for z80-elf.
245 * Add support for relocation of each byte or word of multibyte value to Z80
248 * Add support for Zilog eZ80 (both ADL and Z80 mode) and Zilog Z180 CPUs.
252 * Add command-line option --no-print-map-discarded.
254 * The Cortex-A53 Erratum 843419 workaround now supports a choice of which
255 workaround to use. The option --fix-cortex-a53-843419 now takes an
256 optional argument --fix-cortex-a53-843419[=full|adr|adrp] which can be
257 used to force a particular workaround to be used. See --help for AArch64
260 * Add target handlers for AArch64 for ELF GNU program properties.
262 * Add support for GNU_PROPERTY_AARCH64_FEATURE_1_BTI in ELF GNU program
263 properties in the AArch64 ELF linker.
265 * Add support for GNU_PROPERTY_AARCH64_FEATURE_1_PAC in ELF GNU program
266 properties in the AArch64 ELF linker.
268 * Add -z force-bti for AArch64 to enable GNU_PROPERTY_AARCH64_FEATURE_1_BTI
269 on output while warning about missing GNU_PROPERTY_AARCH64_FEATURE_1_BTI
270 on inputs and use PLTs protected with BTI.
272 * Add -z pac-plt for AArch64 to pick PAC enabled PLTs.
276 * Report property change in linker map file when merging GNU properties.
278 * Add support for the C-SKY processor series.
280 * -t now doesn't report members within archives, unless -t is given twice.
281 A single -t is now more useful when generating a list of files that should be
282 packaged for a linker bug report. For example:
283 gcc hello.c -save-temps -Wl,-t | xargs realpath | sort | uniq > files
284 tar cJf test.tar.xz `cat files`
288 * Speed up direct linking with DLLs for Cygwin and Mingw targets.
290 * Add a configure option --enable-separate-code to decide whether
291 -z separate-code should be enabled in ELF linker by default. Default
292 to yes for Linux/x86 targets. Note that -z separate-code can increase
293 disk and memory size.
297 * Add -z separate-code to generate separate code PT_LOAD segment.
299 * Add "-z undefs" command-line option as the inverse of the "-z defs" option.
301 * Add -z globalaudit command-line option to force audit libraries to be run
302 for every dynamic object loaded by an executable - provided that the loader
303 supports this functionality.
305 * Tighten linker script grammar around file name specifiers to prevent the use
306 of SORT_BY_ALIGNMENT and SORT_BY_INIT_PRIORITY on filenames. These would
307 previously be accepted but had no effect.
309 * The EXCLUDE_FILE directive can now be placed within any SORT_* directive
310 within input section lists.
314 * Support for -z shstk in the x86 ELF linker to generate
315 GNU_PROPERTY_X86_FEATURE_1_SHSTK in ELF GNU program properties.
317 * Add support for GNU_PROPERTY_X86_FEATURE_1_SHSTK in ELF GNU program
318 properties in the x86 ELF linker.
320 * Add support for GNU_PROPERTY_X86_FEATURE_1_IBT in ELF GNU program
321 properties in the x86 ELF linker.
323 * Support for -z ibtplt in the x86 ELF linker to generate IBT-enabled
326 * Support for -z ibt in the x86 ELF linker to generate IBT-enabled
327 PLT as well as GNU_PROPERTY_X86_FEATURE_1_IBT in ELF GNU program
330 * Add support for ELF SHF_GNU_MBIND and PT_GNU_MBIND_XXX.
332 * Add support for ELF GNU program properties.
334 * Add support for the Texas Instruments PRU processor.
336 * When configuring for arc*-*-linux* targets the default linker emulation will
337 change if --with-cpu=nps400 is used at configure time.
339 * Improve assignment of LMAs to orphan sections in some edge cases where a
340 mixture of both AT>LMA_REGION and AT(LMA) are used.
342 * Orphan sections placed after an empty section that has an AT(LMA) will now
343 take an load memory address starting from LMA.
345 * Section groups can now be resolved (the group deleted and the group members
346 placed like normal sections) at partial link time either using the new linker
347 option --force-group-allocation or by placing FORCE_GROUP_ALLOCATION into the
352 * The EXCLUDE_FILE linker script construct can now be applied outside of the
353 section list in order for the exclusions to apply over all input sections in
356 * Add support for the RISC-V architecture.
358 * The command-line option --no-eh-frame-hdr can now be used in ELF based
359 linkers to disable the automatic generation of .eh_frame_hdr sections.
361 * Add --in-implib=<infile> to the ARM linker to enable specifying a set of
362 Secure Gateway veneers that must exist in the output import library specified
363 by --out-implib=<outfile> and the address they must have. As such,
364 --in-implib is only supported in combination with --cmse-implib.
366 * Extended the --out-implib=<file> option, previously restricted to x86 PE
367 targets, to any ELF based target. This allows the generation of an import
368 library for an ELF executable, which can then be used by another application
369 to link against the executable.
373 * Add a configure option --enable-relro to decide whether -z relro should
374 be enabled in ELF linker by default. Default to yes for all Linux
375 targets except FRV, HPPA, IA64 and MIPS. Note that -z relro can increase
376 disk and memory size.
378 * Support for -z noreloc-overflow in the x86-64 ELF linker to disable
379 relocation overflow check.
381 * Add -z common/-z nocommon options for ELF targets to control whether to
382 convert common symbols to the STT_COMMON type during a relocatable link.
384 * Support for -z nodynamic-undefined-weak in the x86 ELF linker, which
385 avoids dynamic relocations against undefined weak symbols in executable.
387 * The NOCROSSREFSTO command was added to the linker script language.
389 * Add --no-apply-dynamic-relocs to the AArch64 linker to do not apply link-time
390 values for dynamic relocations.
394 * Add --fix-stm32l4xx-629360 to the ARM linker to enable a link-time
395 workaround for a bug in the bus matrix / memory controller for some of
396 the STM32 Cortex-M4 based products (STM32L4xx)
398 * Add a configure option --enable-compressed-debug-sections={all,ld} to
399 decide whether DWARF debug sections should be compressed by default.
401 * Add support for the ARC EM/HS, and ARC600/700 architectures.
403 * Experimental support for linker garbage collection (--gc-sections)
404 has been enabled for COFF and PE based targets.
406 * New command-line option for ELF targets to compress DWARF debug
407 sections, --compress-debug-sections=[none|zlib|zlib-gnu|zlib-gabi].
409 * New command-line option, --orphan-handling=[place|warn|error|discard], to
410 adjust how orphan sections are handled. The default is 'place' which gives
411 the current behaviour, 'warn' and 'error' issue a warning or error
412 respectively when orphan sections are found, and 'discard' will discard all
415 * Add support for LLVM plugin.
417 * Add --print-memory-usage option to report memory blocks usage.
419 * Add --require-defined option, it's like --undefined except the new symbol
420 must be defined by the end of the link.
424 * PE binaries now once again contain real timestamps by default. To disable
425 the inclusion of a timestamp in a PE binary, use the --no-insert-timestamp
428 * Replace support for openrisc and or32 with support for or1k.
430 * Add support for the --build-id command-line option to COFF based targets.
432 * x86/x86_64 pe-coff now supports the --build-id option.
434 * Add support for the Andes NDS32.
438 * Add LOG2CEIL() builtin function to the linker script language
440 * Add support for the Texas Instruments MSP430X processor.
442 * Add support for Altera Nios II.
444 * Add support for the V850E3V5 architecture.
446 * Add support for the Imagination Technologies Meta processor.
448 * --enable-new-dtags no longer generates old dtags in addition to new dtags.
450 * Remove linker support for MIPS ECOFF targets.
452 * Add ALIGN_WITH_INPUT to the linker script language to force the alignment of
453 an output section to use the maximum alignment of all its input sections.
457 * Enable compressed debug section feature for x86/x86_64 pe-coff.
459 * Add support for the 64-bit ARM architecture: AArch64.
461 * Added SORT_NONE to the linker script language to disable section sorting.
463 * Add a linker-provided symbol when producing ELF output, '__ehdr_start'
464 to point to the ELF file header (and nearby program headers) in the
465 program's memory image.
467 * Add support for S12X processor.
469 * Add support for the VLE extension to the PowerPC architecture.
471 * Add support for the Freescale XGATE architecture.
473 * Add option -f FILE on AIX (for response file).
475 * Add support for the Renesas RL78 architecture.
477 * Add support for the Adapteva EPIPHANY architecture.
481 * --copy-dt-needed-entries is no longer enabled by default. Instead
482 --no-copy-dt-needed-entries is the default.
484 * INPUT_SECTION_FLAGS has been added to the linker script language
485 to allow selection of input sections by section header section flags.
487 * Add support for the Tilera TILEPro and TILE-Gx architectures.
489 * Added SORT_BY_INIT_PRIORITY to the linker script language to permit
490 sorting sections by numerical value of the GCC init_priority attribute
491 encoded in the section name.
495 * Linker script expression evaluation is somewhat more sane. This may
496 break scripts that depend on quirks of the old expression evaluation.
498 * Turn off underscoring for x86_64 PE+-COFF targets. For old behavior the
499 option --enable-leading-mingw64-underscores can be used on configure of
502 * Add support for the TMS320C6000 (TI C6X) processor family.
504 * --add-needed renamed to --copy-dt-needed-entries in order to avoid confusion
505 with --as-needed option.
507 * Extend .def file syntax by '== <ID>' for imports and exports. This allows
508 to alias the import/export table name written in PE image.
510 * Add --exclude-all-symbols option to PE based linkers. This prevents all
511 symbols from automatically being exported.
513 * Add support for the Renesas RX processor.
515 * Add support for alpha-vms target.
519 * GNU/Linux targets now support the STB_GNU_UNIQUE symbol binding. This is a
520 GNU extension to the standard set of ELF symbol bindings. The binding will
521 be passed on to the dynamic linker which will make sure that in the entire
522 process there is just one symbol with the given name and type in use.
524 * PE targets now support a GNU extension to allow the alignment of common
525 common symbols to be specified. This support uses custom options in
526 the .drectve section, which will be disregarded by the native tools.
528 * PE targets now add primitive support for ELF version scripts; symbols
529 are not versioned, but the local and global symbol visibility directives
530 are respected when filtering symbols in auto-export mode.
532 * New option --no-export-dynamic to undo the effect of the -E and
533 --export-dynamic options.
535 * ELF: --warn-alternate-em option to warn if an object has alternate
538 * New script function REGION_ALIAS to add alias names to memory regions.
540 * PE targets no longer make use of the long section names PE extension to
541 the COFF format when generating executable images, by default. The old
542 (slightly non-conformant) behaviour can still be invoked by using the
543 new '--enable-long-section-names' command-line option. It is also enabled
544 automatically in the presence of un-stripped debug information, as GDB
545 needs to be able to find the debug info sections by their full names.
547 * For GNU/Linux systems the linker will now avoid processing any relocations
548 made against symbols of the STT_GNU_IFUNC type and instead emit them into
549 the resulting binary for processing by the loader.
551 * --as-needed now links in a dynamic library if it satisfies undefined
552 symbols in regular objects, or in other dynamic libraries. In the
553 latter case the library is not linked if it is found in a DT_NEEDED
554 entry of one of the libraries already linked.
556 * Add a new command-line option, -Ttext-segment ADDR, for ELF targets
557 to set the address of the first byte of the text segment.
559 * Add support for Sunplus score architecture.
561 * Add new option --use-nul-prefixed-import-tables to ld for PE targets to
562 allow fallback to old import table generation with null element prefix.
564 * Windows PE systems now support a new --exclude-modules-for-implib option,
565 allowing users to partition object files and archive members between a DLL
566 and its associated import library as they are generated during linking.
568 * Add support for Lattice Mico32 (lm32) architecture.
570 * Add CR16 ELF --embedded-relocs (used to embedded relocations into binaries
571 for Embedded-PIC code) option.
573 * Add to the PE/PE+ targets the support of two different kinds of
574 pseudo-relocations. They can be selected by the switches
575 --enable-runtime-pseudo-reloc-v1 and --enable-runtime-pseudo-reloc-v2.
576 For the switch --enable-runtime-pseudo-reloc it uses for 32-bit
577 runtime pseudo relocation version one, for 64-bit the version two.
581 * Linker scripts support a new INSERT command that makes it easier to
582 augment the default script.
584 * Linker script input section filespecs may now specify a file within an
585 archive by writing "archive:file".
587 * The --sort-common switch now has an optional argument which specifies the
588 direction of sorting.
590 * The M68K linker now supports multiple GOT generation schemes controlled via
591 the --got=<type> command-line option.
593 * The ARM EABI linker will now generate stubs for function calls to symbols
594 that are too far away. The placement of the stubs is controlled by a new
595 linker command-line option: --stub-group-size=N.
599 * Linker sources now released under version 3 of the GNU General Public
602 * ELF: New --build-id option to generate a unique per-binary identifier
603 embedded in a note section.
605 * Added support for National Semicondutor CompactRISC (ie CR16) target.
607 * -l:foo now searches the library path for a filename called foo,
608 without converting it to libfoo.a or libfoo.so.
610 * Add a new command-line option '--default-script=FILE' or '-dT FILE'
611 which specifies a replacement for the built in, default linker
614 * ELF: Add -Bsymbolic-functions, --dynamic-list-cpp-new, which puts C++
615 operator new and delete on the dynamic list, and --dynamic-list-data,
616 builtin list for --dynamic-list, which puts global data symbols on the
619 * Add support for x86_64 PE+ target.
621 * Add support for Score target.
623 * ELF: Add --dynamic-list option to specify a list of global symbols
624 whose references shouldn't be bound to the definition within the
625 shared library, or a list of symbols which should be added to the
626 symbol table in the executable.
628 * The default output section LMA has changed for allocatable sections from
629 being equal to VMA, to keeping the difference between LMA and VMA the same as
630 the previous output section in the same region. This is a more useful
631 default when using overlays and other cases where you specify an LMA
632 differing from the VMA for some sections.
634 * New switch: --print-gc-sections to list any sections removed by garabge
637 * ARM: Added --vfp11-denorm-fix option to work around an erratum in current
642 * Support for the Infineon XC16X has been added by KPIT Cummins Infosystems.
644 * Modify the Linux linker search order to better match ld.so search order.
645 Look for DT_NEEDED libraries in paths specified by ld.so.conf before
646 searching the default directories, rather than vice versa.
647 Use $prefix/etc/ld.so.conf if it exists, otherwise /etc/ld.so.conf.
649 * PE-COFF: Forward exports from DLL's can now be specified in .def files
650 passed directly to ld.
652 * Support for the Z80 processor family has been added.
654 * Add support for the "@<file>" syntax to the command line, so that extra
655 switches can be read from <file>.
659 * Support for the R_ARM_V4BX relocation as defined in the ARM AAELF
660 specification has been added via the --fix-v4bx command-line option.
662 * New linker script construct AS_NEEDED(), which sets the --as-needed flag
663 for input files listed inside of it.
665 * A new command-line option, --sysroot, can be used to override the
666 default sysroot location. It only applies to toolchains that were
667 configured using --with-sysroot.
669 * New linker script functions: ORIGIN() and LENGTH() which return information
670 about a specified memory region.
672 * Port to MAXQ processor contributed by HCL Tech.
674 * Added SEGMENT_START to the linker script language to permit the user to
675 override the base address for a segment from the command-line.
677 * ELF: --warn-shared-textrel option to warn if adding a DT_TEXTREL to a shared
680 * Added SORT_BY_NAME and SORT_BY_ALIGNMENT to the linker script
681 language to permit sorting sections by section name or section
684 * Added a new linker command-line switch, --sort-section name|alignment,
685 to sort sections by section name or maximum alignment.
687 * ELF: --add-needed/--no-add-needed options to control if a DT_NEEDED tag
688 should be added when a shared library comes from DT_NEEDED tags.
690 * Support for the crx-elf target added.
692 * Support for the sh-symbianelf target added.
694 * A new linker command-line switch has been added which allows the hash table
695 size to be set to a suitable prime value near to its argument. This switch
696 is --hash-size=<NUMBER>. Also if the switch --reduce-memory-overheads is
697 used, and --hash-size has not been used, then the default value will be set
700 * Linker map files are now generated with an O(N) algorithm for finding symbols
701 that are defined in each section. This uses about 40% more memory for
702 symbols than the old O(N^2) algorithm. You can use the new
703 --reduce-memory-overheads option to select the old algorithm; this option
704 might also be used in the future to select similar tradeoffs.
708 * ELF: --as-needed/--no-as-needed options to control if a DT_NEEDED tag should
709 be added only when a shared library is referenced.
711 * PE: --large-address-aware option to indicate executables support virtual
712 addresses greater than 2 gigabytes.
714 * DWARF 2 support for i386pe added.
716 * The linker script operator DEFINED() will now yield 1 only for a symbol that
717 is defined before the statement where DEFINED is used.
719 * The MIPS --embedded-relocs (used to embed relocations into binaries for
720 Embedded-PIC code) is deprecated and will be removed in a future release.
722 * cr16c support added by NSC.
724 * m32r Linux (ELF) support added by Renesas.
726 * Improved linker's handling of unresolved symbols. The switch
727 --unresolved-symbols=<method> has been added to tell the linker when it
728 should report them and the switch --warn-unresolved-symbols has been added to
729 make reports be issued as warning messages rather than errors.
733 * Added support for Xtensa architecture.
735 * Added --with-sysroot configure switch to specify a target system root, for
736 linking against a target filesystem image.
738 * Added --accept-unknown-linker-format to restore old linker behaviour (pre
739 2.14) of silently accepting and linking in any files in an unknown binary
742 * Added --no-omagic to undo the effects of the -N option.
744 * Support for Texas Instruments TMS320C4x and TMS320C3x series of
745 DSP's contributed by Michael Hayes and Svein E. Seldal.
747 * Added --with-lib-path configure switch to specify default value for
750 * ARM port to QNX operating system added by Graeme Peterson.
752 * IP2K support added by Denis Chertykov.
756 * Support for the Fujitsu FRV architecture added by Red Hat. Models for FR400
759 Changes in version 2.13:
761 * DEC VAX ELF support, by Matt Thomas.
763 Changes in version 2.12:
765 * Support for Don Knuth's MMIX, by Hans-Peter Nilsson.
767 * Support for the OpenRISC 32-bit embedded processor by OpenCores.
769 * Support for -z nocopyreloc in the x86 ELF linker, which disables
770 production of copy relocs. Warning: using this option may result in
771 non-sharable applications.
773 * Support for -z combreloc in the ELF linker, which puts dynamic
774 relocations against the same symbol together, so that dynamic linker
775 can use an one-entry symbol lookup cache.
777 * Support for ELF SHF_MERGE section merging, by Jakub Jelinek.
779 Changes in version 2.11:
781 * Support for AMD x86-64 architecture, by Jan Hubicka, SuSE Labs.
783 * Support added for eliminating duplicate DWARF2 debug information by
784 having the compiler generate the information in sections called
785 .gnu.linkonce.wi.XXXX where XXXX is a checksum for the contents. The
786 linker then merges these sections together into the normal .debug_info
789 * The native ELF linker now searches the directories in DT_RUNPATH or
790 DT_RPATH of a shared library for shared libraries needed by it.
792 * TI C54x support, by Timothy Wall.
794 * Added command-line switch --section-start to set the start address of any
797 * Added ability to emit full relocation information in linked executables,
798 enabled by --emit-relocs. Some post-linkage optimization tools need
799 this information in order to be able to correctly identify and perform
800 symbol relative addressing in the event of changes in section contents
801 (instructions being added or deleted, extending data sections, etc.)
803 * Support for i860, by Jason Eckhardt (preliminary, alpha quality).
805 * Support for CRIS (Axis Communications ETRAX series).
807 * Support for PDP-11 and 2.11BSD a.out format, by Lars Brinkhoff.
809 Changes in version 2.10:
811 * Added AT> to the linker script language to allow load-time allocation of
812 sections into regions.
814 * Added garbage collection of unused sections, enabled by --gc-sections.
815 It does require a bit of backend support; currently implemented are
816 arm-elf, avr-elf, d10v-elf, fr30-elf, i386-elf, m32r-elf, m68k-elf,
817 mcore-elf, mips-elf, mn10300-elf, ppc-elf, sh-elf, sparc-elf, and v850-elf.
818 Others will ignore the option.
820 * Added SORT to the linker script language to permit sorting sections by file
821 name or section name.
823 * Added EXTERN to the linker script language as an equivalent to the -u
826 * Added ASSERT to the linker script language.
828 * Added EXCLUDE_FILE to the linker script language for further control over
831 * Added -O option to optimize linker output (as of this writing, this only
832 affects ELF shared library generation).
834 * The -e option now accepts a number as well as a symbol name.
836 * Added --no-undefined option to disallow undefined symbols when creating a
839 * The linker now issues a warning, not an error, for an undefined symbol when
840 using -Bsymbolic; use the new --no-undefined option to get the old
843 * Added --demangle and --no-demangle options.
845 Changes in version 2.9:
847 * Added SQUAD to the linker script language.
849 * New option --no-warn-mismatch.
851 * The MEMORY command now parses the attributes to determine where sections that
852 are not placed in a specific memory region are placed.
854 Changes in version 2.8:
856 * Linker scripts may now contain shell wildcard characters for file and section
859 * The linker now supports symbol versions in ELF.
861 * The NOCROSSREFS command was added to the linker script language.
863 * The LOADADDR expression was added to the linker script language.
865 * MAX and MIN functions were added to the linker script language.
867 * The OVERLAY construct was added to the linker script language.
869 * New option --warn-section-align to warn when the address of an output section
870 changes due to alignment of an input section.
872 * New options --filter/-F and --auxiliary/-f.
874 Changes in version 2.7:
876 * New option --cref to print out a cross reference table.
878 * New option --wrap SYMBOL.
880 * New option --no-whole-archive, to turn off the effect of --whole-archive.
882 * Input sections assigned to the output section /DISCARD/ in the linker script
883 are not included in the output file.
885 * The SunOS and ELF linkers now merge stabs debugging information which uses
886 the N_BINCL and N_EINCL stab types. This reduces the amount of debugging
887 information generated.
889 Changes in version 2.6:
891 * When an ELF section name is representable as a C identifier (this is not true
892 of most ELF section names), the linker will automatically define symbols
893 __start_SECNAME and __stop_SECNAME, where SECNAME is the section name, at the
894 beginning and the end of the section. This is used by glibc.
896 Addendum: Current versions of the linker (at least for version 2.18 onwards
897 and possibly much earlier as well) place two restrictions on this feature: The
898 symbols are only implemented for orphaned sections, not for explicitly placed
899 sections and they are PROVIDEd rather than being defined.
901 * When an ELF section named .gnu.warning is encountered in an input file, the
902 contents of the section are displayed as an error message, and the section is
903 not copied into the output file. This is used by glibc.
905 * When an ELF section named .gnu.warning.SYMBOL is encountered in an input
906 file, and the symbol SYMBOL is referenced by some object file, the contents of
907 the section are displayed as an error message. The section is not copied into
908 the output file, unless doing a relocatable or shared link. This is used by
911 * New options -split-by-reloc and -split-by-file.
913 * The linker now supports linking PIC compiled code on SPARC SunOS. It can
914 also create SPARC SunOS shared libraries, and, like the native SunOS linker,
915 will do so whenever there is an undefined symbol in the link and neither the -e
916 nor the -r option was used.
918 * The -rpath option may be used on SunOS to set the list of directories to be
919 searched at run time. This overrides the default of building the list from the
922 * The COFF linker now combines debugging information for structs, unions, and
923 enums, so that even if the same type is defined in multiple input files it will
924 only be defined once in the output file. The --traditional-format switch will
925 prevent this optimization.
927 Changes in version 2.5:
929 * The linker now supports linking against SunOS shared libraries. It still can
930 not link SunOS PIC (Position Independent Code) files, so it can not be used to
931 generate shared libraries.
933 * The linker now supports linking against ELF shared libraries for the i386
934 (UnixWare) and SPARC (Solaris). It can also link ELF PIC files, and can be
935 used to generate shared libraries. Shared library generation is not well
936 tested; please report any problems encountered. The linker is now enabled for
939 * Eric Youngdale has contributed Linux support code, including linking against
940 Linux a.out shared libraries. The linker produces Linux QMAGIC binaries.
942 * The ELF backend has been converted to the new linker code. To use the new
943 ELF linker, each particular target requires a relocation function. So far,
944 this function has been written for i386 (UnixWare), SPARC (Solaris) MIPS (Irix
945 5), and HPPA ELF targets.
947 * The -( (--start-group) and -) (--end-group) options have been added to
948 support searching a group of archives as though they were a single archive.
949 This can also be used in a linker script, as GROUP ( files ).
951 * When a file is named on the command line, and the linker does not recognize
952 it as an object file, the linker will now treat the file as a linker script
953 file. A linker script named in this way augments, but does not replace, the
954 default linker script.
956 * The -warn-once option was added. It causes the linker to only warn once per
957 undefined symbol, rather than once per reference.
959 * The COFF backend has been converted to the new linker code. As with ELF, to
960 use the new linker, each particular target requires a relocation function. So
961 far, this function has been written for the i386, m68k, a29k and SH targets.
963 * The -V flag was made a synonym for -v, for SVR4 compatibility. The old -V
964 behaviour is available via --verbose.
966 Changes in version 2.4:
968 * New linker code, by Steve Chamberlain and Ian Taylor. For a.out and ecoff
969 formats (so far), this should result in considerable savings in time
970 and memory used while linking; slightly poorer performance than
971 before for formats not converted yet.
973 * Command-line parsing is no longer done with flex. This means
974 oddball characters in filenames won't get treated as argument
977 * HP-PA ELF support, by Jeff Law. (No SOM support yet.)
979 * Mach i386 support, by David Mackenzie.
981 * Irix 4 shared libraries are now supported (Irix 5 uses ELF, and ELF shared
982 libraries are not yet supported).
984 * COFF shared libraries (as on SCO) should work as well.
986 * The linker is disabled for Solaris. (Actually, it was in 2.3 also, I just
987 forgot to note it.) Some of their C library routines don't work when
988 statically linked, and the GNU linker doesn't support dynamic linking yet.
990 Changes in version 2.3:
992 * Weak symbols are now supported.
994 * ELF support has been added. The linker has been bootstrapped on
995 UnixWare and Solaris.
997 * Alpha OSF/1 support has been added (non dynamic linking only).
999 Changes in version 2.2:
1001 * The `bfd' library has been updated to reduce a.out-format string
1002 table size. The effect of this is that files linked from many input
1003 files with duplicate symbols (`-g' debugging records, or identical
1004 static symbols) should be much smaller.
1006 Changes in version 2.1:
1008 * The ld -ySYMBOL flag (to trace references to SYMBOL) is now implemented.
1010 * There is now support for writing ECOFF files, so ld and the
1011 other utilities should work on Risc/Ultrix and Irix.
1014 Copyright (C) 2012-2024 Free Software Foundation, Inc.
1016 Copying and distribution of this file, with or without modification,
1017 are permitted in any medium without royalty provided the copyright
1018 notice and this notice are preserved.