3 * The linker now deduplicates the types in .ctf sections. The new
4 command-line option --ctf-share-types describes how to do this:
5 its default value, share-unconflicted, produces the most compact
8 * The linker now omits the "variable section" from .ctf sections by
9 default, saving space. This is almost certainly what you want
10 unless you are working on a project that has its own analogue
11 of symbol tables that are not reflected in the ELF symtabs.
15 * X86 NaCl target support is removed.
17 * Add ELF linker command-line options, --export-dynamic-symbol and
18 --export-dynamic-symbol-list, to make symbols dynamic.
20 * Add a configure option, --enable-textrel-check=[no|yes|warning|error],
21 to decide what ELF linker should do by default with DT_TEXTREL in an
22 executable or shared library. Default to yes for Linux/x86 targets.
24 * The -Map=<filename> command line option has been extended so that if
25 <filename> is a directory then <filename>/<output-filename>.map will be
28 * Add a command-line option for ELF linker, --warn-textrel, to warn that
29 DT_TEXTREL is set in a position-independent executable or shared object.
31 * Add command-line options --enable-non-contiguous-regions and
32 --enable-non-contiguous-regions-warnings.
34 * Add command-line option --imagic for the pdp11-aout target to output format
35 IMAGIC (0411) for separate instruction and data spaces, and change the
36 default format option for pdp11-aout to be --omagic.
38 * Relative pathnames in INPUT() and GROUP() directives in linker scripts are
39 searched relative to the directory of the linker script before other search
42 * Add ELF linker command-line option `-z start-stop-visibility=...' to control
43 the visibility of synthetic `__start_SECNAME` and `__stop_SECNAME` symbols.
45 * Add command-line option --dependency-file to write a Make-style dependency
46 file listing the input files consulted by the linker, like the files written
47 by the compiler's -M -MP options.
51 * The ld check for "PHDR segment not covered by LOAD segment" is more
52 effective, catching cases that were wrongly allowed by previous versions of
53 ld. If you see this error it is likely you are linking with a bad linker
54 script or the binary you are building is not intended to be loaded by a
55 dynamic loader. In the latter case --no-dynamic-linker is appropriate.
57 * cr16c support removed.
59 * Add support for z80-elf.
61 * Add support for relocation of each byte or word of multibyte value to Z80
64 * Add support for Zilog eZ80 (both ADL and Z80 mode) and Zilog Z180 CPUs.
68 * Add command-line option --no-print-map-discarded.
70 * The Cortex-A53 Erratum 843419 workaround now supports a choice of which
71 workaround to use. The option --fix-cortex-a53-843419 now takes an
72 optional argument --fix-cortex-a53-843419[=full|adr|adrp] which can be
73 used to force a particular workaround to be used. See --help for AArch64
76 * Add target handlers for AArch64 for ELF GNU program properties.
78 * Add support for GNU_PROPERTY_AARCH64_FEATURE_1_BTI in ELF GNU program
79 properties in the AArch64 ELF linker.
81 * Add support for GNU_PROPERTY_AARCH64_FEATURE_1_PAC in ELF GNU program
82 properties in the AArch64 ELF linker.
84 * Add -z force-bti for AArch64 to enable GNU_PROPERTY_AARCH64_FEATURE_1_BTI
85 on output while warning about missing GNU_PROPERTY_AARCH64_FEATURE_1_BTI
86 on inputs and use PLTs protected with BTI.
88 * Add -z pac-plt for AArch64 to pick PAC enabled PLTs.
92 * Report property change in linker map file when merging GNU properties.
94 * Add support for the C-SKY processor series.
96 * -t now doesn't report members within archives, unless -t is given twice.
97 A single -t is now more useful when generating a list of files that should be
98 packaged for a linker bug report. For example:
99 gcc hello.c -save-temps -Wl,-t | xargs realpath | sort | uniq > files
100 tar cJf test.tar.xz `cat files`
104 * Speed up direct linking with DLLs for Cygwin and Mingw targets.
106 * Add a configure option --enable-separate-code to decide whether
107 -z separate-code should be enabled in ELF linker by default. Default
108 to yes for Linux/x86 targets. Note that -z separate-code can increase
109 disk and memory size.
113 * Add -z separate-code to generate separate code PT_LOAD segment.
115 * Add "-z undefs" command-line option as the inverse of the "-z defs" option.
117 * Add -z globalaudit command-line option to force audit libraries to be run
118 for every dynamic object loaded by an executable - provided that the loader
119 supports this functionality.
121 * Tighten linker script grammar around file name specifiers to prevent the use
122 of SORT_BY_ALIGNMENT and SORT_BY_INIT_PRIORITY on filenames. These would
123 previously be accepted but had no effect.
125 * The EXCLUDE_FILE directive can now be placed within any SORT_* directive
126 within input section lists.
130 * Support for -z shstk in the x86 ELF linker to generate
131 GNU_PROPERTY_X86_FEATURE_1_SHSTK in ELF GNU program properties.
133 * Add support for GNU_PROPERTY_X86_FEATURE_1_SHSTK in ELF GNU program
134 properties in the x86 ELF linker.
136 * Add support for GNU_PROPERTY_X86_FEATURE_1_IBT in ELF GNU program
137 properties in the x86 ELF linker.
139 * Support for -z ibtplt in the x86 ELF linker to generate IBT-enabled
142 * Support for -z ibt in the x86 ELF linker to generate IBT-enabled
143 PLT as well as GNU_PROPERTY_X86_FEATURE_1_IBT in ELF GNU program
146 * Add support for ELF SHF_GNU_MBIND and PT_GNU_MBIND_XXX.
148 * Add support for ELF GNU program properties.
150 * Add support for the Texas Instruments PRU processor.
152 * When configuring for arc*-*-linux* targets the default linker emulation will
153 change if --with-cpu=nps400 is used at configure time.
155 * Improve assignment of LMAs to orphan sections in some edge cases where a
156 mixture of both AT>LMA_REGION and AT(LMA) are used.
158 * Orphan sections placed after an empty section that has an AT(LMA) will now
159 take an load memory address starting from LMA.
161 * Section groups can now be resolved (the group deleted and the group members
162 placed like normal sections) at partial link time either using the new linker
163 option --force-group-allocation or by placing FORCE_GROUP_ALLOCATION into the
168 * The EXCLUDE_FILE linker script construct can now be applied outside of the
169 section list in order for the exclusions to apply over all input sections in
172 * Add support for the RISC-V architecture.
174 * The command-line option --no-eh-frame-hdr can now be used in ELF based
175 linkers to disable the automatic generation of .eh_frame_hdr sections.
177 * Add --in-implib=<infile> to the ARM linker to enable specifying a set of
178 Secure Gateway veneers that must exist in the output import library specified
179 by --out-implib=<outfile> and the address they must have. As such,
180 --in-implib is only supported in combination with --cmse-implib.
182 * Extended the --out-implib=<file> option, previously restricted to x86 PE
183 targets, to any ELF based target. This allows the generation of an import
184 library for an ELF executable, which can then be used by another application
185 to link against the executable.
189 * Add a configure option --enable-relro to decide whether -z relro should
190 be enabled in ELF linker by default. Default to yes for all Linux
191 targets except FRV, HPPA, IA64 and MIPS. Note that -z relro can increase
192 disk and memory size.
194 * Support for -z noreloc-overflow in the x86-64 ELF linker to disable
195 relocation overflow check.
197 * Add -z common/-z nocommon options for ELF targets to control whether to
198 convert common symbols to the STT_COMMON type during a relocatable link.
200 * Support for -z nodynamic-undefined-weak in the x86 ELF linker, which
201 avoids dynamic relocations against undefined weak symbols in executable.
203 * The NOCROSSREFSTO command was added to the linker script language.
205 * Add --no-apply-dynamic-relocs to the AArch64 linker to do not apply link-time
206 values for dynamic relocations.
210 * Add --fix-stm32l4xx-629360 to the ARM linker to enable a link-time
211 workaround for a bug in the bus matrix / memory controller for some of
212 the STM32 Cortex-M4 based products (STM32L4xx)
214 * Add a configure option --enable-compressed-debug-sections={all,ld} to
215 decide whether DWARF debug sections should be compressed by default.
217 * Add support for the ARC EM/HS, and ARC600/700 architectures.
219 * Experimental support for linker garbage collection (--gc-sections)
220 has been enabled for COFF and PE based targets.
222 * New command-line option for ELF targets to compress DWARF debug
223 sections, --compress-debug-sections=[none|zlib|zlib-gnu|zlib-gabi].
225 * New command-line option, --orphan-handling=[place|warn|error|discard], to
226 adjust how orphan sections are handled. The default is 'place' which gives
227 the current behaviour, 'warn' and 'error' issue a warning or error
228 respectively when orphan sections are found, and 'discard' will discard all
231 * Add support for LLVM plugin.
233 * Add --print-memory-usage option to report memory blocks usage.
235 * Add --require-defined option, it's like --undefined except the new symbol
236 must be defined by the end of the link.
240 * PE binaries now once again contain real timestamps by default. To disable
241 the inclusion of a timestamp in a PE binary, use the --no-insert-timestamp
244 * Replace support for openrisc and or32 with support for or1k.
246 * Add support for the --build-id command-line option to COFF based targets.
248 * x86/x86_64 pe-coff now supports the --build-id option.
250 * Add support for the Andes NDS32.
254 * Add LOG2CEIL() builtin function to the linker script language
256 * Add support for the Texas Instruments MSP430X processor.
258 * Add support for Altera Nios II.
260 * Add support for the V850E3V5 architecture.
262 * Add support for the Imagination Technologies Meta processor.
264 * --enable-new-dtags no longer generates old dtags in addition to new dtags.
266 * Remove linker support for MIPS ECOFF targets.
268 * Add ALIGN_WITH_INPUT to the linker script language to force the alignment of
269 an output section to use the maximum alignment of all its input sections.
273 * Enable compressed debug section feature for x86/x86_64 pe-coff.
275 * Add support for the 64-bit ARM architecture: AArch64.
277 * Added SORT_NONE to the linker script language to disable section sorting.
279 * Add a linker-provided symbol when producing ELF output, '__ehdr_start'
280 to point to the ELF file header (and nearby program headers) in the
281 program's memory image.
283 * Add support for S12X processor.
285 * Add support for the VLE extension to the PowerPC architecture.
287 * Add support for the Freescale XGATE architecture.
289 * Add option -f FILE on AIX (for response file).
291 * Add support for the Renesas RL78 architecture.
293 * Add support for the Adapteva EPIPHANY architecture.
297 * --copy-dt-needed-entries is no longer enabled by default. Instead
298 --no-copy-dt-needed-entries is the default.
300 * INPUT_SECTION_FLAGS has been added to the linker script language
301 to allow selection of input sections by section header section flags.
303 * Add support for the Tilera TILEPro and TILE-Gx architectures.
305 * Added SORT_BY_INIT_PRIORITY to the linker script language to permit
306 sorting sections by numerical value of the GCC init_priority attribute
307 encoded in the section name.
311 * Linker script expression evaluation is somewhat more sane. This may
312 break scripts that depend on quirks of the old expression evaluation.
314 * Turn off underscoring for x86_64 PE+-COFF targets. For old behavior the
315 option --enable-leading-mingw64-underscores can be used on configure of
318 * Add support for the TMS320C6000 (TI C6X) processor family.
320 * --add-needed renamed to --copy-dt-needed-entries in order to avoid confusion
321 with --as-needed option.
323 * Extend .def file syntax by '== <ID>' for imports and exports. This allows
324 to alias the import/export table name written in PE image.
326 * Add --exclude-all-symbols option to PE based linkers. This prevents all
327 symbols from automatically being exported.
329 * Add support for the Renesas RX processor.
331 * Add support for alpha-vms target.
335 * GNU/Linux targets now support the STB_GNU_UNIQUE symbol binding. This is a
336 GNU extension to the standard set of ELF symbol bindings. The binding will
337 be passed on to the dynamic linker which will make sure that in the entire
338 process there is just one symbol with the given name and type in use.
340 * PE targets now support a GNU extension to allow the alignment of common
341 common symbols to be specified. This support uses custom options in
342 the .drectve section, which will be disregarded by the native tools.
344 * PE targets now add primitive support for ELF version scripts; symbols
345 are not versioned, but the local and global symbol visibility directives
346 are respected when filtering symbols in auto-export mode.
348 * New option --no-export-dynamic to undo the effect of the -E and
349 --export-dynamic options.
351 * ELF: --warn-alternate-em option to warn if an object has alternate
354 * New script function REGION_ALIAS to add alias names to memory regions.
356 * PE targets no longer make use of the long section names PE extension to
357 the COFF format when generating executable images, by default. The old
358 (slightly non-conformant) behaviour can still be invoked by using the
359 new '--enable-long-section-names' command-line option. It is also enabled
360 automatically in the presence of un-stripped debug information, as GDB
361 needs to be able to find the debug info sections by their full names.
363 * For GNU/Linux systems the linker will now avoid processing any relocations
364 made against symbols of the STT_GNU_IFUNC type and instead emit them into
365 the resulting binary for processing by the loader.
367 * --as-needed now links in a dynamic library if it satisfies undefined
368 symbols in regular objects, or in other dynamic libraries. In the
369 latter case the library is not linked if it is found in a DT_NEEDED
370 entry of one of the libraries already linked.
372 * Add a new command-line option, -Ttext-segment ADDR, for ELF targets
373 to set the address of the first byte of the text segment.
375 * Add support for Sunplus score architecture.
377 * Add new option --use-nul-prefixed-import-tables to ld for PE targets to
378 allow fallback to old import table generation with null element prefix.
380 * Windows PE systems now support a new --exclude-modules-for-implib option,
381 allowing users to partition object files and archive members between a DLL
382 and its associated import library as they are generated during linking.
384 * Add support for Lattice Mico32 (lm32) architecture.
386 * Add CR16 ELF --embedded-relocs (used to embedded relocations into binaries
387 for Embedded-PIC code) option.
389 * Add to the PE/PE+ targets the support of two different kinds of
390 pseudo-relocations. They can be selected by the switches
391 --enable-runtime-pseudo-reloc-v1 and --enable-runtime-pseudo-reloc-v2.
392 For the switch --enable-runtime-pseudo-reloc it uses for 32-bit
393 runtime pseudo relocation version one, for 64-bit the version two.
397 * Linker scripts support a new INSERT command that makes it easier to
398 augment the default script.
400 * Linker script input section filespecs may now specify a file within an
401 archive by writing "archive:file".
403 * The --sort-common switch now has an optional argument which specifies the
404 direction of sorting.
406 * The M68K linker now supports multiple GOT generation schemes controlled via
407 the --got=<type> command-line option.
409 * The ARM EABI linker will now generate stubs for function calls to symbols
410 that are too far away. The placement of the stubs is controlled by a new
411 linker command-line option: --stub-group-size=N.
415 * Linker sources now released under version 3 of the GNU General Public
418 * ELF: New --build-id option to generate a unique per-binary identifier
419 embedded in a note section.
421 * Added support for National Semicondutor CompactRISC (ie CR16) target.
423 * -l:foo now searches the library path for a filename called foo,
424 without converting it to libfoo.a or libfoo.so.
426 * Add a new command-line option '--default-script=FILE' or '-dT FILE'
427 which specifies a replacement for the built in, default linker
430 * ELF: Add -Bsymbolic-functions, --dynamic-list-cpp-new, which puts C++
431 operator new and delete on the dynamic list, and --dynamic-list-data,
432 builtin list for --dynamic-list, which puts global data symbols on the
435 * Add support for x86_64 PE+ target.
437 * Add support for Score target.
439 * ELF: Add --dynamic-list option to specify a list of global symbols
440 whose references shouldn't be bound to the definition within the
441 shared library, or a list of symbols which should be added to the
442 symbol table in the executable.
444 * The default output section LMA has changed for allocatable sections from
445 being equal to VMA, to keeping the difference between LMA and VMA the same as
446 the previous output section in the same region. This is a more useful
447 default when using overlays and other cases where you specify an LMA
448 differing from the VMA for some sections.
450 * New switch: --print-gc-sections to list any sections removed by garabge
453 * ARM: Added --vfp11-denorm-fix option to work around an erratum in current
458 * Support for the Infineon XC16X has been added by KPIT Cummins Infosystems.
460 * Modify the Linux linker search order to better match ld.so search order.
461 Look for DT_NEEDED libraries in paths specified by ld.so.conf before
462 searching the default directories, rather than vice versa.
463 Use $prefix/etc/ld.so.conf if it exists, otherwise /etc/ld.so.conf.
465 * PE-COFF: Forward exports from DLL's can now be specified in .def files
466 passed directly to ld.
468 * Support for the Z80 processor family has been added.
470 * Add support for the "@<file>" syntax to the command line, so that extra
471 switches can be read from <file>.
475 * Support for the R_ARM_V4BX relocation as defined in the ARM AAELF
476 specification has been added via the --fix-v4bx command-line option.
478 * New linker script construct AS_NEEDED(), which sets the --as-needed flag
479 for input files listed inside of it.
481 * A new command-line option, --sysroot, can be used to override the
482 default sysroot location. It only applies to toolchains that were
483 configured using --with-sysroot.
485 * New linker script functions: ORIGIN() and LENGTH() which return information
486 about a specified memory region.
488 * Port to MAXQ processor contributed by HCL Tech.
490 * Added SEGMENT_START to the linker script language to permit the user to
491 override the base address for a segment from the command-line.
493 * ELF: --warn-shared-textrel option to warn if adding a DT_TEXTREL to a shared
496 * Added SORT_BY_NAME and SORT_BY_ALIGNMENT to the linker script
497 language to permit sorting sections by section name or section
500 * Added a new linker command-line switch, --sort-section name|alignment,
501 to sort sections by section name or maximum alignment.
503 * ELF: --add-needed/--no-add-needed options to control if a DT_NEEDED tag
504 should be added when a shared library comes from DT_NEEDED tags.
506 * Support for the crx-elf target added.
508 * Support for the sh-symbianelf target added.
510 * A new linker command-line switch has been added which allows the hash table
511 size to be set to a suitable prime value near to its argument. This switch
512 is --hash-size=<NUMBER>. Also if the switch --reduce-memory-overheads is
513 used, and --hash-size has not been used, then the default value will be set
516 * Linker map files are now generated with an O(N) algorithm for finding symbols
517 that are defined in each section. This uses about 40% more memory for
518 symbols than the old O(N^2) algorithm. You can use the new
519 --reduce-memory-overheads option to select the old algorithm; this option
520 might also be used in the future to select similar tradeoffs.
524 * ELF: --as-needed/--no-as-needed options to control if a DT_NEEDED tag should
525 be added only when a shared library is referenced.
527 * PE: --large-address-aware option to indicate executables support virtual
528 addresses greater than 2 gigabytes.
530 * DWARF 2 support for i386pe added.
532 * The linker script operator DEFINED() will now yield 1 only for a symbol that
533 is defined before the statement where DEFINED is used.
535 * The MIPS --embedded-relocs (used to embed relocations into binaries for
536 Embedded-PIC code) is deprecated and will be removed in a future release.
538 * cr16c support added by NSC.
540 * m32r Linux (ELF) support added by Renesas.
542 * Improved linker's handling of unresolved symbols. The switch
543 --unresolved-symbols=<method> has been added to tell the linker when it
544 should report them and the switch --warn-unresolved-symbols has been added to
545 make reports be issued as warning messages rather than errors.
549 * Added support for Xtensa architecture.
551 * Added --with-sysroot configure switch to specify a target system root, for
552 linking against a target filesystem image.
554 * Added --accept-unknown-linker-format to restore old linker behaviour (pre
555 2.14) of silently accepting and linking in any files in an unknown binary
558 * Added --no-omagic to undo the effects of the -N option.
560 * Support for Texas Instruments TMS320C4x and TMS320C3x series of
561 DSP's contributed by Michael Hayes and Svein E. Seldal.
563 * Added --with-lib-path configure switch to specify default value for
566 * ARM port to QNX operating system added by Graeme Peterson.
568 * IP2K support added by Denis Chertykov.
572 * Support for the Fujitsu FRV architecture added by Red Hat. Models for FR400
575 Changes in version 2.13:
577 * DEC VAX ELF support, by Matt Thomas.
579 Changes in version 2.12:
581 * Support for Don Knuth's MMIX, by Hans-Peter Nilsson.
583 * Support for the OpenRISC 32-bit embedded processor by OpenCores.
585 * Support for -z nocopyreloc in the x86 ELF linker, which disables
586 production of copy relocs. Warning: using this option may result in
587 non-sharable applications.
589 * Support for -z combreloc in the ELF linker, which puts dynamic
590 relocations against the same symbol together, so that dynamic linker
591 can use an one-entry symbol lookup cache.
593 * Support for ELF SHF_MERGE section merging, by Jakub Jelinek.
595 Changes in version 2.11:
597 * Support for AMD x86-64 architecture, by Jan Hubicka, SuSE Labs.
599 * Support added for eliminating duplicate DWARF2 debug information by
600 having the compiler generate the information in sections called
601 .gnu.linkonce.wi.XXXX where XXXX is a checksum for the contents. The
602 linker then merges these sections together into the normal .debug_info
605 * The native ELF linker now searches the directories in DT_RUNPATH or
606 DT_RPATH of a shared library for shared libraries needed by it.
608 * TI C54x support, by Timothy Wall.
610 * Added command-line switch --section-start to set the start address of any
613 * Added ability to emit full relocation information in linked executables,
614 enabled by --emit-relocs. Some post-linkage optimization tools need
615 this information in order to be able to correctly identify and perform
616 symbol relative addressing in the event of changes in section contents
617 (instructions being added or deleted, extending data sections, etc.)
619 * Support for i860, by Jason Eckhardt (preliminary, alpha quality).
621 * Support for CRIS (Axis Communications ETRAX series).
623 * Support for PDP-11 and 2.11BSD a.out format, by Lars Brinkhoff.
625 Changes in version 2.10:
627 * Added AT> to the linker script language to allow load-time allocation of
628 sections into regions.
630 * Added garbage collection of unused sections, enabled by --gc-sections.
631 It does require a bit of backend support; currently implemented are
632 arm-elf, avr-elf, d10v-elf, fr30-elf, i386-elf, m32r-elf, m68k-elf,
633 mcore-elf, mips-elf, mn10300-elf, ppc-elf, sh-elf, sparc-elf, and v850-elf.
634 Others will ignore the option.
636 * Added SORT to the linker script language to permit sorting sections by file
637 name or section name.
639 * Added EXTERN to the linker script language as an equivalent to the -u
642 * Added ASSERT to the linker script language.
644 * Added EXCLUDE_FILE to the linker script language for further control over
647 * Added -O option to optimize linker output (as of this writing, this only
648 affects ELF shared library generation).
650 * The -e option now accepts a number as well as a symbol name.
652 * Added --no-undefined option to disallow undefined symbols when creating a
655 * The linker now issues a warning, not an error, for an undefined symbol when
656 using -Bsymbolic; use the new --no-undefined option to get the old
659 * Added --demangle and --no-demangle options.
661 Changes in version 2.9:
663 * Added SQUAD to the linker script language.
665 * New option --no-warn-mismatch.
667 * The MEMORY command now parses the attributes to determine where sections that
668 are not placed in a specific memory region are placed.
670 Changes in version 2.8:
672 * Linker scripts may now contain shell wildcard characters for file and section
675 * The linker now supports symbol versions in ELF.
677 * The NOCROSSREFS command was added to the linker script language.
679 * The LOADADDR expression was added to the linker script language.
681 * MAX and MIN functions were added to the linker script language.
683 * The OVERLAY construct was added to the linker script language.
685 * New option --warn-section-align to warn when the address of an output section
686 changes due to alignment of an input section.
688 * New options --filter/-F and --auxiliary/-f.
690 Changes in version 2.7:
692 * New option --cref to print out a cross reference table.
694 * New option --wrap SYMBOL.
696 * New option --no-whole-archive, to turn off the effect of --whole-archive.
698 * Input sections assigned to the output section /DISCARD/ in the linker script
699 are not included in the output file.
701 * The SunOS and ELF linkers now merge stabs debugging information which uses
702 the N_BINCL and N_EINCL stab types. This reduces the amount of debugging
703 information generated.
705 Changes in version 2.6:
707 * When an ELF section name is representable as a C identifier (this is not true
708 of most ELF section names), the linker will automatically define symbols
709 __start_SECNAME and __stop_SECNAME, where SECNAME is the section name, at the
710 beginning and the end of the section. This is used by glibc.
712 Addendum: Current versions of the linker (at least for version 2.18 onwards
713 and possibly much earlier as well) place two restrictions on this feature: The
714 symbols are only implemented for orphaned sections, not for explicitly placed
715 sections and they are PROVIDEd rather than being defined.
717 * When an ELF section named .gnu.warning is encountered in an input file, the
718 contents of the section are displayed as an error message, and the section is
719 not copied into the output file. This is used by glibc.
721 * When an ELF section named .gnu.warning.SYMBOL is encountered in an input
722 file, and the symbol SYMBOL is referenced by some object file, the contents of
723 the section are displayed as an error message. The section is not copied into
724 the output file, unless doing a relocatable or shared link. This is used by
727 * New options -split-by-reloc and -split-by-file.
729 * The linker now supports linking PIC compiled code on SPARC SunOS. It can
730 also create SPARC SunOS shared libraries, and, like the native SunOS linker,
731 will do so whenever there is an undefined symbol in the link and neither the -e
732 nor the -r option was used.
734 * The -rpath option may be used on SunOS to set the list of directories to be
735 searched at run time. This overrides the default of building the list from the
738 * The COFF linker now combines debugging information for structs, unions, and
739 enums, so that even if the same type is defined in multiple input files it will
740 only be defined once in the output file. The --traditional-format switch will
741 prevent this optimization.
743 Changes in version 2.5:
745 * The linker now supports linking against SunOS shared libraries. It still can
746 not link SunOS PIC (Position Independent Code) files, so it can not be used to
747 generate shared libraries.
749 * The linker now supports linking against ELF shared libraries for the i386
750 (UnixWare) and SPARC (Solaris). It can also link ELF PIC files, and can be
751 used to generate shared libraries. Shared library generation is not well
752 tested; please report any problems encountered. The linker is now enabled for
755 * Eric Youngdale has contributed Linux support code, including linking against
756 Linux a.out shared libraries. The linker produces Linux QMAGIC binaries.
758 * The ELF backend has been converted to the new linker code. To use the new
759 ELF linker, each particular target requires a relocation function. So far,
760 this function has been written for i386 (UnixWare), SPARC (Solaris) MIPS (Irix
761 5), and HPPA ELF targets.
763 * The -( (--start-group) and -) (--end-group) options have been added to
764 support searching a group of archives as though they were a single archive.
765 This can also be used in a linker script, as GROUP ( files ).
767 * When a file is named on the command line, and the linker does not recognize
768 it as an object file, the linker will now treat the file as a linker script
769 file. A linker script named in this way augments, but does not replace, the
770 default linker script.
772 * The -warn-once option was added. It causes the linker to only warn once per
773 undefined symbol, rather than once per reference.
775 * The COFF backend has been converted to the new linker code. As with ELF, to
776 use the new linker, each particular target requires a relocation function. So
777 far, this function has been written for the i386, m68k, a29k and SH targets.
779 * The -V flag was made a synonym for -v, for SVR4 compatibility. The old -V
780 behaviour is available via --verbose.
782 Changes in version 2.4:
784 * New linker code, by Steve Chamberlain and Ian Taylor. For a.out and ecoff
785 formats (so far), this should result in considerable savings in time
786 and memory used while linking; slightly poorer performance than
787 before for formats not converted yet.
789 * Command-line parsing is no longer done with flex. This means
790 oddball characters in filenames won't get treated as argument
793 * HP-PA ELF support, by Jeff Law. (No SOM support yet.)
795 * Mach i386 support, by David Mackenzie.
797 * Irix 4 shared libraries are now supported (Irix 5 uses ELF, and ELF shared
798 libraries are not yet supported).
800 * COFF shared libraries (as on SCO) should work as well.
802 * The linker is disabled for Solaris. (Actually, it was in 2.3 also, I just
803 forgot to note it.) Some of their C library routines don't work when
804 statically linked, and the GNU linker doesn't support dynamic linking yet.
806 Changes in version 2.3:
808 * Weak symbols are now supported.
810 * ELF support has been added. The linker has been bootstrapped on
811 UnixWare and Solaris.
813 * Alpha OSF/1 support has been added (non dynamic linking only).
815 Changes in version 2.2:
817 * The `bfd' library has been updated to reduce a.out-format string
818 table size. The effect of this is that files linked from many input
819 files with duplicate symbols (`-g' debugging records, or identical
820 static symbols) should be much smaller.
822 Changes in version 2.1:
824 * The ld -ySYMBOL flag (to trace references to SYMBOL) is now implemented.
826 * There is now support for writing ECOFF files, so ld and the
827 other utilities should work on Risc/Ultrix and Irix.
830 Copyright (C) 2012-2020 Free Software Foundation, Inc.
832 Copying and distribution of this file, with or without modification,
833 are permitted in any medium without royalty provided the copyright
834 notice and this notice are preserved.