1 \input texinfo.tex @c -*-texinfo-*-
4 @setfilename gccinstall.info
9 @include gcc-common.texi
11 @c Specify title for specific html page
13 @settitle Installing GCC
16 @settitle Host/Target specific installation notes for GCC
18 @ifset prerequisiteshtml
19 @settitle Prerequisites for GCC
22 @settitle Downloading GCC
25 @settitle Installing GCC: Configuration
28 @settitle Installing GCC: Building
31 @settitle Installing GCC: Testing
33 @ifset finalinstallhtml
34 @settitle Installing GCC: Final installation
37 @settitle Installing GCC: Binaries
40 @settitle Installing GCC: GNU Free Documentation License
43 @c Copyright (C) 1988-2022 Free Software Foundation, Inc.
44 @c *** Converted to texinfo by Dean Wakerley, dean@wakerley.com
46 @c IMPORTANT: whenever you modify this file, run `install.texi2html' to
47 @c test the generation of HTML documents for the gcc.gnu.org web pages.
49 @c Do not use @footnote{} in this file as it breaks install.texi2html!
51 @c Include everything if we're not making html
55 @set prerequisiteshtml
65 @c Part 2 Summary Description and Copyright
67 Copyright @copyright{} 1988-2022 Free Software Foundation, Inc.
69 Permission is granted to copy, distribute and/or modify this document
70 under the terms of the GNU Free Documentation License, Version 1.3 or
71 any later version published by the Free Software Foundation; with no
72 Invariant Sections, the Front-Cover texts being (a) (see below), and
73 with the Back-Cover Texts being (b) (see below). A copy of the
74 license is included in the section entitled ``@uref{./gfdl.html,,GNU
75 Free Documentation License}''.
77 (a) The FSF's Front-Cover Text is:
81 (b) The FSF's Back-Cover Text is:
83 You have freedom to copy and modify this GNU Manual, like GNU
84 software. Copies published by the Free Software Foundation raise
85 funds for GNU development.
90 @dircategory Software development
92 * gccinstall: (gccinstall). Installing the GNU Compiler Collection.
95 @c Part 3 Titlepage and Copyright
100 @c The following two commands start the copyright page.
102 @vskip 0pt plus 1filll
106 @c Part 4 Top node, Master Menu, and/or Table of Contents
109 @comment node-name, next, Previous, up
112 * Installing GCC:: This document describes the generic installation
113 procedure for GCC as well as detailing some target
114 specific installation instructions.
116 * Specific:: Host/target specific installation notes for GCC.
117 * Binaries:: Where to get pre-compiled binaries.
119 * GNU Free Documentation License:: How you can copy and share this manual.
120 * Concept Index:: This index has two entries.
128 @c Part 5 The Body of the Document
129 @c ***Installing GCC**********************************************************
131 @comment node-name, next, previous, up
132 @node Installing GCC, Binaries, , Top
136 @chapter Installing GCC
139 The latest version of this document is always available at
140 @uref{https://gcc.gnu.org/install/,,https://gcc.gnu.org/install/}.
141 It refers to the current development sources, instructions for
142 specific released versions are included with the sources.
144 This document describes the generic installation procedure for GCC as well
145 as detailing some target specific installation instructions.
147 GCC includes several components that previously were separate distributions
148 with their own installation instructions. This document supersedes all
149 package-specific installation instructions.
151 @emph{Before} starting the build/install procedure please check the
153 @ref{Specific, host/target specific installation notes}.
156 @uref{specific.html,,host/target specific installation notes}.
158 We recommend you browse the entire generic installation instructions before
161 Lists of successful builds for released versions of GCC are
162 available at @uref{https://gcc.gnu.org/buildstat.html}.
163 These lists are updated as new information becomes available.
165 The installation procedure itself is broken into five steps.
170 * Downloading the source::
173 * Testing:: (optional)
180 @uref{prerequisites.html,,Prerequisites}
182 @uref{download.html,,Downloading the source}
184 @uref{configure.html,,Configuration}
186 @uref{build.html,,Building}
188 @uref{test.html,,Testing} (optional)
190 @uref{finalinstall.html,,Final install}
194 Please note that GCC does not support @samp{make uninstall} and probably
195 won't do so in the near future as this would open a can of worms. Instead,
196 we suggest that you install GCC into a directory of its own and simply
197 remove that directory when you do not need that specific version of GCC
198 any longer, and, if shared libraries are installed there as well, no
199 more binaries exist that use them.
206 @uref{./index.html,,Return to the GCC Installation page}
212 @c ***Prerequisites**************************************************
214 @comment node-name, next, previous, up
215 @node Prerequisites, Downloading the source, , Installing GCC
217 @ifset prerequisiteshtml
219 @chapter Prerequisites
221 @cindex Prerequisites
223 GCC requires that various tools and packages be available for use in the
224 build procedure. Modifying GCC sources requires additional tools
227 @heading Tools/packages necessary for building GCC
229 @item ISO C++11 compiler
230 Necessary to bootstrap GCC.
232 Versions of GCC prior to 11 also allow bootstrapping with an ISO C++98
233 compiler, versions of GCC prior to 4.8 also allow bootstrapping with a
234 ISO C89 compiler, and versions of GCC prior to 3.4 also allow
235 bootstrapping with a traditional (K&R) C compiler.
237 To build all languages in a cross-compiler or other configuration where
238 3-stage bootstrap is not performed, you need to start with an existing
239 GCC binary (version 4.8 or later) because source code for language
240 frontends other than C might use GCC extensions.
242 @item C standard library and headers
244 In order to build GCC, the C standard library and headers must be present
245 for all target variants for which target libraries will be built (and not
246 only the variant of the host C++ compiler).
248 This affects the popular @samp{x86_64-pc-linux-gnu} platform (among
249 other multilib targets), for which 64-bit (@samp{x86_64}) and 32-bit
250 (@samp{i386}) libc headers are usually packaged separately. If you do a
251 build of a native compiler on @samp{x86_64-pc-linux-gnu}, make sure you
252 either have the 32-bit libc developer package properly installed (the exact
253 name of the package depends on your distro) or you must build GCC as a
254 64-bit only compiler by configuring with the option
255 @option{--disable-multilib}. Otherwise, you may encounter an error such as
256 @samp{fatal error: gnu/stubs-32.h: No such file}
258 @item @anchor{GNAT-prerequisite}GNAT
260 In order to build GNAT, the Ada compiler, you need a working GNAT
261 compiler (GCC version 5.1 or later).
263 This includes GNAT tools such as @command{gnatmake} and
264 @command{gnatlink}, since the Ada front end is written in Ada and
265 uses some GNAT-specific extensions.
267 In order to build a cross compiler, it is strongly recommended to install
268 the new compiler as native first, and then use it to build the cross
269 compiler. Other native compiler versions may work but this is not guaranteed and
270 will typically fail with hard to understand compilation errors during the
273 Similarly, it is strongly recommended to use an older version of GNAT to build
274 GNAT. More recent versions of GNAT than the version built are not guaranteed
275 to work and will often fail during the build with compilation errors.
277 Note that @command{configure} does not test whether the GNAT installation works
278 and has a sufficiently recent version; if too old a GNAT version is
279 installed and @option{--enable-languages=ada} is used, the build will fail.
281 @env{ADA_INCLUDE_PATH} and @env{ADA_OBJECT_PATH} environment variables
282 must not be set when building the Ada compiler, the Ada tools, or the
283 Ada runtime libraries. You can check that your build environment is clean
284 by verifying that @samp{gnatls -v} lists only one explicit path in each
287 @item @anchor{GDC-prerequisite}GDC
289 In order to build GDC, the D compiler, you need a working GDC
290 compiler (GCC version 9.1 or later) and D runtime library,
291 @samp{libphobos}, as the D front end is written in D.
293 Versions of GDC prior to 12 can be built with an ISO C++11 compiler, which can
294 then be installed and used to bootstrap newer versions of the D front end.
296 It is strongly recommended to use an older version of GDC to build GDC. More
297 recent versions of GDC than the version built are not guaranteed to work and
298 will often fail during the build with compilation errors relating to
299 deprecations or removed features.
301 Note that @command{configure} does not test whether the GDC installation works
302 and has a sufficiently recent version. Though the implementation of the D
303 front end does not make use of any GDC-specific extensions, or novel features
304 of the D language, if too old a GDC version is installed and
305 @option{--enable-languages=d} is used, the build will fail.
307 On some targets, @samp{libphobos} isn't enabled by default, but compiles
308 and works if @option{--enable-libphobos} is used. Specifics are
309 documented for affected targets.
311 @item A ``working'' POSIX compatible shell, or GNU bash
313 Necessary when running @command{configure} because some
314 @command{/bin/sh} shells have bugs and may crash when configuring the
315 target libraries. In other cases, @command{/bin/sh} or @command{ksh}
316 have disastrous corner-case performance problems. This
317 can cause target @command{configure} runs to literally take days to
318 complete in some cases.
320 So on some platforms @command{/bin/ksh} is sufficient, on others it
321 isn't. See the host/target specific instructions for your platform, or
322 use @command{bash} to be sure. Then set @env{CONFIG_SHELL} in your
323 environment to your ``good'' shell prior to running
324 @command{configure}/@command{make}.
326 @command{zsh} is not a fully compliant POSIX shell and will not
327 work when configuring GCC@.
329 @item A POSIX or SVR4 awk
331 Necessary for creating some of the generated source files for GCC@.
332 If in doubt, use a recent GNU awk version, as some of the older ones
333 are broken. GNU awk version 3.1.5 is known to work.
337 Necessary in some circumstances, optional in others. See the
338 host/target specific instructions for your platform for the exact
341 Note binutils 2.35 or newer is required for LTO to work correctly
342 with GNU libtool that includes doing a bootstrap with LTO enabled.
344 @item gzip version 1.2.4 (or later) or
345 @itemx bzip2 version 1.0.2 (or later)
347 Necessary to uncompress GCC @command{tar} files when source code is
348 obtained via HTTPS mirror sites.
350 @item GNU make version 3.80 (or later)
352 You must have GNU make installed to build GCC@.
354 @item GNU tar version 1.14 (or later)
356 Necessary (only on some platforms) to untar the source code. Many
357 systems' @command{tar} programs will also work, only try GNU
358 @command{tar} if you have problems.
360 @item Perl version between 5.6.1 and 5.6.24
362 Necessary when targeting Darwin, building @samp{libstdc++},
363 and not using @option{--disable-symvers}.
364 Necessary when targeting Solaris 2 with Solaris @command{ld} and not using
365 @option{--disable-symvers}.
367 Necessary when regenerating @file{Makefile} dependencies in libiberty.
368 Necessary when regenerating @file{libiberty/functions.texi}.
369 Necessary when generating manpages from Texinfo manuals.
370 Used by various scripts to generate some files included in the source
371 repository (mainly Unicode-related and rarely changing) from source
374 Used by @command{automake}.
378 Several support libraries are necessary to build GCC, some are required,
379 others optional. While any sufficiently new version of required tools
380 usually work, library requirements are generally stricter. Newer
381 versions may work in some cases, but it's safer to use the exact
382 versions documented. We appreciate bug reports about problems with
383 newer versions, though. If your OS vendor provides packages for the
384 support libraries then using those packages may be the simplest way to
385 install the libraries.
388 @item GNU Multiple Precision Library (GMP) version 4.3.2 (or later)
390 Necessary to build GCC@. If a GMP source distribution is found in a
391 subdirectory of your GCC sources named @file{gmp}, it will be built
392 together with GCC. Alternatively, if GMP is already installed but it
393 is not in your library search path, you will have to configure with the
394 @option{--with-gmp} configure option. See also @option{--with-gmp-lib}
395 and @option{--with-gmp-include}.
396 The in-tree build is only supported with the GMP version that
397 download_prerequisites installs.
399 @item MPFR Library version 3.1.0 (or later)
401 Necessary to build GCC@. It can be downloaded from
402 @uref{https://www.mpfr.org}. If an MPFR source distribution is found
403 in a subdirectory of your GCC sources named @file{mpfr}, it will be
404 built together with GCC. Alternatively, if MPFR is already installed
405 but it is not in your default library search path, the
406 @option{--with-mpfr} configure option should be used. See also
407 @option{--with-mpfr-lib} and @option{--with-mpfr-include}.
408 The in-tree build is only supported with the MPFR version that
409 download_prerequisites installs.
411 @item MPC Library version 1.0.1 (or later)
413 Necessary to build GCC@. It can be downloaded from
414 @uref{https://www.multiprecision.org/mpc/}. If an MPC source distribution
415 is found in a subdirectory of your GCC sources named @file{mpc}, it
416 will be built together with GCC. Alternatively, if MPC is already
417 installed but it is not in your default library search path, the
418 @option{--with-mpc} configure option should be used. See also
419 @option{--with-mpc-lib} and @option{--with-mpc-include}.
420 The in-tree build is only supported with the MPC version that
421 download_prerequisites installs.
423 @item isl Library version 0.15 or later.
425 Necessary to build GCC with the Graphite loop optimizations.
426 It can be downloaded from @uref{https://gcc.gnu.org/pub/gcc/infrastructure/}.
427 If an isl source distribution is found
428 in a subdirectory of your GCC sources named @file{isl}, it will be
429 built together with GCC. Alternatively, the @option{--with-isl} configure
430 option should be used if isl is not installed in your default library
435 Necessary to build GCC with zstd compression used for LTO bytecode.
436 The library is searched in your default library patch search.
437 Alternatively, the @option{--with-zstd} configure option should be used.
441 @heading Tools/packages necessary for modifying GCC
443 @item autoconf version 2.69
444 @itemx GNU m4 version 1.4.6 (or later)
446 Necessary when modifying @file{configure.ac}, @file{aclocal.m4}, etc.@:
447 to regenerate @file{configure} and @file{config.in} files.
449 @item automake version 1.15.1
451 Necessary when modifying a @file{Makefile.am} file to regenerate its
452 associated @file{Makefile.in}.
454 Much of GCC does not use automake, so directly edit the @file{Makefile.in}
455 file. Specifically this applies to the @file{gcc}, @file{intl},
456 @file{libcpp}, @file{libiberty}, @file{libobjc} directories as well
457 as any of their subdirectories.
459 For directories that use automake, GCC requires the latest release in
460 the 1.15 series, which is currently 1.15.1. When regenerating a directory
461 to a newer version, please update all the directories using an older 1.15
462 to the latest released version.
464 @item gettext version 0.14.5 (or later)
466 Needed to regenerate @file{gcc.pot}.
468 @item gperf version 2.7.2 (or later)
470 Necessary when modifying @command{gperf} input files, e.g.@:
471 @file{gcc/cp/cfns.gperf} to regenerate its associated header file, e.g.@:
472 @file{gcc/cp/cfns.h}.
474 @item DejaGnu version 1.5.3 (or later)
477 @c Once Tcl 8.5 or higher is required, remove any obsolete
478 @c compatibility workarounds:
479 @c git grep 'compatibility with earlier Tcl releases'
481 Necessary to run the GCC testsuite; see the section on testing for
484 @item autogen version 5.5.4 (or later) and
485 @itemx guile version 1.4.1 (or later)
487 Necessary to regenerate @file{fixinc/fixincl.x} from
488 @file{fixinc/inclhack.def} and @file{fixinc/*.tpl}.
490 Necessary to run @samp{make check} for @file{fixinc}.
492 Necessary to regenerate the top level @file{Makefile.in} file from
493 @file{Makefile.tpl} and @file{Makefile.def}.
495 @item Flex version 2.5.4 (or later)
497 Necessary when modifying @file{*.l} files.
499 Necessary to build GCC during development because the generated output
500 files are not included in the version-controlled source repository.
501 They are included in releases.
503 @item Texinfo version 4.7 (or later)
505 Necessary for running @command{makeinfo} when modifying @file{*.texi}
506 files to test your changes.
508 Necessary for running @command{make dvi} or @command{make pdf} to
509 create printable documentation in DVI or PDF format. Texinfo version
510 4.8 or later is required for @command{make pdf}.
512 Necessary to build GCC documentation during development because the
513 generated output files are not included in the repository. They are
514 included in releases.
516 @item @TeX{} (any working version)
518 Necessary for running @command{texi2dvi} and @command{texi2pdf}, which
519 are used when running @command{make dvi} or @command{make pdf} to create
520 DVI or PDF files, respectively.
522 @item Sphinx version 1.0 (or later)
524 Necessary to regenerate @file{jit/docs/_build/texinfo} from the @file{.rst}
525 files in the directories below @file{jit/docs}.
527 @item git (any version)
528 @itemx SSH (any version)
530 Necessary to access the source repository. Public releases and weekly
531 snapshots of the development sources are also available via HTTPS@.
533 @item GNU diffutils version 2.7 (or later)
535 Useful when submitting patches for the GCC source code.
537 @item patch version 2.5.4 (or later)
539 Necessary when applying patches, created with @command{diff}, to one's
549 @uref{./index.html,,Return to the GCC Installation page}
553 @c ***Downloading the source**************************************************
555 @comment node-name, next, previous, up
556 @node Downloading the source, Configuration, Prerequisites, Installing GCC
560 @chapter Downloading GCC
562 @cindex Downloading GCC
563 @cindex Downloading the Source
565 GCC is distributed via @uref{https://gcc.gnu.org/git.html,,git} and via
566 HTTPS as tarballs compressed with @command{gzip} or @command{bzip2}.
568 Please refer to the @uref{https://gcc.gnu.org/releases.html,,releases web page}
569 for information on how to obtain GCC@.
571 The source distribution includes the C, C++, Objective-C, Fortran,
572 and Ada (in the case of GCC 3.1 and later) compilers, as well as
573 runtime libraries for C++, Objective-C, and Fortran.
574 For previous versions these were downloadable as separate components such
575 as the core GCC distribution, which included the C language front end and
576 shared components, and language-specific distributions including the
577 language front end and the language runtime (where appropriate).
579 If you also intend to build binutils (either to upgrade an existing
580 installation or for use in place of the corresponding tools of your
581 OS), unpack the binutils distribution either in the same directory or
582 a separate one. In the latter case, add symbolic links to any
583 components of the binutils you intend to build alongside the compiler
584 (@file{bfd}, @file{binutils}, @file{gas}, @file{gprof}, @file{ld},
585 @file{opcodes}, @dots{}) to the directory containing the GCC sources.
587 Likewise the GMP, MPFR and MPC libraries can be automatically built
588 together with GCC. You may simply run the
589 @command{contrib/download_prerequisites} script in the GCC source directory
590 to set up everything.
591 Otherwise unpack the GMP, MPFR and/or MPC source
592 distributions in the directory containing the GCC sources and rename
593 their directories to @file{gmp}, @file{mpfr} and @file{mpc},
594 respectively (or use symbolic links with the same name).
601 @uref{./index.html,,Return to the GCC Installation page}
605 @c ***Configuration***********************************************************
607 @comment node-name, next, previous, up
608 @node Configuration, Building, Downloading the source, Installing GCC
612 @chapter Installing GCC: Configuration
614 @cindex Configuration
615 @cindex Installing GCC: Configuration
617 Like most GNU software, GCC must be configured before it can be built.
618 This document describes the recommended configuration procedure
619 for both native and cross targets.
621 We use @var{srcdir} to refer to the toplevel source directory for
622 GCC; we use @var{objdir} to refer to the toplevel build/object directory.
624 If you obtained the sources by cloning the repository, @var{srcdir}
625 must refer to the top @file{gcc} directory, the one where the
626 @file{MAINTAINERS} file can be found, and not its @file{gcc}
627 subdirectory, otherwise the build will fail.
629 If either @var{srcdir} or @var{objdir} is located on an automounted NFS
630 file system, the shell's built-in @command{pwd} command will return
631 temporary pathnames. Using these can lead to various sorts of build
632 problems. To avoid this issue, set the @env{PWDCMD} environment
633 variable to an automounter-aware @command{pwd} command, e.g.,
634 @command{pawd} or @samp{amq -w}, during the configuration and build
637 First, we @strong{highly} recommend that GCC be built into a
638 separate directory from the sources which does @strong{not} reside
639 within the source tree. This is how we generally build GCC; building
640 where @var{srcdir} == @var{objdir} should still work, but doesn't
641 get extensive testing; building where @var{objdir} is a subdirectory
642 of @var{srcdir} is unsupported.
644 If you have previously built GCC in the same directory for a
645 different target machine, do @samp{make distclean} to delete all files
646 that might be invalid. One of the files this deletes is @file{Makefile};
647 if @samp{make distclean} complains that @file{Makefile} does not exist
648 or issues a message like ``don't know how to make distclean'' it probably
649 means that the directory is already suitably clean. However, with the
650 recommended method of building in a separate @var{objdir}, you should
651 simply use a different @var{objdir} for each target.
653 Second, when configuring a native system, either @command{cc} or
654 @command{gcc} must be in your path or you must set @env{CC} in
655 your environment before running configure. Otherwise the configuration
659 Note that the bootstrap compiler and the resulting GCC must be link
660 compatible, else the bootstrap will fail with linker errors about
661 incompatible object file formats. Several multilibed targets are
662 affected by this requirement, see
664 @ref{Specific, host/target specific installation notes}.
667 @uref{specific.html,,host/target specific installation notes}.
676 % @var{srcdir}/configure [@var{options}] [@var{target}]
679 @heading Distributor options
681 If you will be distributing binary versions of GCC, with modifications
682 to the source code, you should use the options described in this
683 section to make clear that your version contains modifications.
686 @item --with-pkgversion=@var{version}
687 Specify a string that identifies your package. You may wish
688 to include a build number or build date. This version string will be
689 included in the output of @command{gcc --version}. This suffix does
690 not replace the default version string, only the @samp{GCC} part.
692 The default value is @samp{GCC}.
694 @item --with-bugurl=@var{url}
695 Specify the URL that users should visit if they wish to report a bug.
696 You are of course welcome to forward bugs reported to you to the FSF,
697 if you determine that they are not bugs in your modifications.
699 The default value refers to the FSF's GCC bug tracker.
701 @item --with-documentation-root-url=@var{url}
702 Specify the URL root that contains GCC option documentation. The @var{url}
703 should end with a @code{/} character.
705 The default value is @uref{https://gcc.gnu.org/onlinedocs/,,https://gcc.gnu.org/onlinedocs/}.
707 @item --with-changes-root-url=@var{url}
708 Specify the URL root that contains information about changes in GCC
709 releases like @code{gcc-@var{version}/changes.html}.
710 The @var{url} should end with a @code{/} character.
712 The default value is @uref{https://gcc.gnu.org/,,https://gcc.gnu.org/}.
716 @heading Host, Build and Target specification
718 Specify the host, build and target machine configurations. You do this
719 when you run the @file{configure} script.
721 The @dfn{build} machine is the system which you are using, the
722 @dfn{host} machine is the system where you want to run the resulting
723 compiler (normally the build machine), and the @dfn{target} machine is
724 the system for which you want the compiler to generate code.
726 If you are building a compiler to produce code for the machine it runs
727 on (a native compiler), you normally do not need to specify any operands
728 to @file{configure}; it will try to guess the type of machine you are on
729 and use that as the build, host and target machines. So you don't need
730 to specify a configuration when building a native compiler unless
731 @file{configure} cannot figure out what your configuration is or guesses
734 In those cases, specify the build machine's @dfn{configuration name}
735 with the @option{--host} option; the host and target will default to be
736 the same as the host machine.
741 ./configure --host=x86_64-pc-linux-gnu
744 A configuration name may be canonical or it may be more or less
745 abbreviated (@file{config.sub} script produces canonical versions).
747 A canonical configuration name has three parts, separated by dashes.
748 It looks like this: @samp{@var{cpu}-@var{company}-@var{system}}.
750 Here are the possible CPU types:
753 aarch64, aarch64_be, alpha, alpha64, amdgcn, arc, arceb, arm, armeb, avr, bfin,
754 bpf, cr16, cris, csky, epiphany, fido, fr30, frv, ft32, h8300, hppa, hppa2.0,
755 hppa64, i486, i686, ia64, iq2000, lm32, loongarch64, m32c, m32r, m32rle, m68k,
756 mcore, microblaze, microblazeel, mips, mips64, mips64el, mips64octeon,
757 mips64orion, mips64vr, mipsel, mipsisa32, mipsisa32r2, mipsisa64, mipsisa64r2,
758 mipsisa64r2el, mipsisa64sb1, mipsisa64sr71k, mipstx39, mmix, mn10300, moxie,
759 msp430, nds32be, nds32le, nios2, nvptx, or1k, pdp11, powerpc, powerpc64,
760 powerpc64le, powerpcle, pru, riscv32, riscv32be, riscv64, riscv64be, rl78, rx,
761 s390, s390x, sh, shle, sparc, sparc64, tic6x, tilegx, tilegxbe, tilepro, v850,
762 v850e, v850e1, vax, visium, x86_64, xstormy16, xtensa
765 Here is a list of system types:
768 aix@var{version}, amdhsa, aout, cygwin, darwin@var{version},
769 eabi, eabialtivec, eabisim, eabisimaltivec, elf, elf32,
770 elfbare, elfoabi, freebsd@var{version}, gnu, hpux, hpux@var{version},
771 kfreebsd-gnu, kopensolaris-gnu, linux-androideabi, linux-gnu,
772 linux-gnu_altivec, linux-musl, linux-uclibc, lynxos, mingw32, mingw32crt,
773 mmixware, msdosdjgpp, netbsd, netbsdelf@var{version}, nto-qnx, openbsd,
774 rtems, solaris@var{version}, symbianelf, tpf, uclinux, uclinux_eabi, vms,
775 vxworks, vxworksae, vxworksmils
778 @heading Options specification
780 Use @var{options} to override several configure time options for
781 GCC@. A list of supported @var{options} follows; @samp{configure
782 --help} may list other options, but those not listed below may not
783 work and should not normally be used.
785 Note that each @option{--enable} option has a corresponding
786 @option{--disable} option and that each @option{--with} option has a
787 corresponding @option{--without} option.
790 @item --prefix=@var{dirname}
791 Specify the toplevel installation
792 directory. This is the recommended way to install the tools into a directory
793 other than the default. The toplevel installation directory defaults to
796 We @strong{highly} recommend against @var{dirname} being the same or a
797 subdirectory of @var{objdir} or vice versa. If specifying a directory
798 beneath a user's home directory tree, some shells will not expand
799 @var{dirname} correctly if it contains the @samp{~} metacharacter; use
802 The following standard @command{autoconf} options are supported. Normally you
803 should not need to use these options.
805 @item --exec-prefix=@var{dirname}
806 Specify the toplevel installation directory for architecture-dependent
807 files. The default is @file{@var{prefix}}.
809 @item --bindir=@var{dirname}
810 Specify the installation directory for the executables called by users
811 (such as @command{gcc} and @command{g++}). The default is
812 @file{@var{exec-prefix}/bin}.
814 @item --libdir=@var{dirname}
815 Specify the installation directory for object code libraries and
816 internal data files of GCC@. The default is @file{@var{exec-prefix}/lib}.
818 @item --libexecdir=@var{dirname}
819 Specify the installation directory for internal executables of GCC@.
820 The default is @file{@var{exec-prefix}/libexec}.
822 @item --with-slibdir=@var{dirname}
823 Specify the installation directory for the shared libgcc library. The
824 default is @file{@var{libdir}}.
826 @item --datarootdir=@var{dirname}
827 Specify the root of the directory tree for read-only architecture-independent
828 data files referenced by GCC@. The default is @file{@var{prefix}/share}.
830 @item --infodir=@var{dirname}
831 Specify the installation directory for documentation in info format.
832 The default is @file{@var{datarootdir}/info}.
834 @item --datadir=@var{dirname}
835 Specify the installation directory for some architecture-independent
836 data files referenced by GCC@. The default is @file{@var{datarootdir}}.
838 @item --docdir=@var{dirname}
839 Specify the installation directory for documentation files (other
840 than Info) for GCC@. The default is @file{@var{datarootdir}/doc}.
842 @item --htmldir=@var{dirname}
843 Specify the installation directory for HTML documentation files.
844 The default is @file{@var{docdir}}.
846 @item --pdfdir=@var{dirname}
847 Specify the installation directory for PDF documentation files.
848 The default is @file{@var{docdir}}.
850 @item --mandir=@var{dirname}
851 Specify the installation directory for manual pages. The default is
852 @file{@var{datarootdir}/man}. (Note that the manual pages are only extracts
853 from the full GCC manuals, which are provided in Texinfo format. The manpages
854 are derived by an automatic conversion process from parts of the full
857 @item --with-gxx-include-dir=@var{dirname}
859 the installation directory for G++ header files. The default depends
860 on other configuration options, and differs between cross and native
863 @item --with-specs=@var{specs}
864 Specify additional command line driver SPECS.
865 This can be useful if you need to turn on a non-standard feature by
866 default without modifying the compiler's source code, for instance
867 @option{--with-specs=%@{!fcommon:%@{!fno-common:-fno-common@}@}}.
869 @xref{Spec Files,, Specifying subprocesses and the switches to pass to them,
870 gcc, Using the GNU Compiler Collection (GCC)},
873 See ``Spec Files'' in the main manual
878 @item --program-prefix=@var{prefix}
879 GCC supports some transformations of the names of its programs when
880 installing them. This option prepends @var{prefix} to the names of
881 programs to install in @var{bindir} (see above). For example, specifying
882 @option{--program-prefix=foo-} would result in @samp{gcc}
883 being installed as @file{/usr/local/bin/foo-gcc}.
885 @item --program-suffix=@var{suffix}
886 Appends @var{suffix} to the names of programs to install in @var{bindir}
887 (see above). For example, specifying @option{--program-suffix=-3.1}
888 would result in @samp{gcc} being installed as
889 @file{/usr/local/bin/gcc-3.1}.
891 @item --program-transform-name=@var{pattern}
892 Applies the @samp{sed} script @var{pattern} to be applied to the names
893 of programs to install in @var{bindir} (see above). @var{pattern} has to
894 consist of one or more basic @samp{sed} editing commands, separated by
895 semicolons. For example, if you want the @samp{gcc} program name to be
896 transformed to the installed program @file{/usr/local/bin/myowngcc} and
897 the @samp{g++} program name to be transformed to
898 @file{/usr/local/bin/gspecial++} without changing other program names,
899 you could use the pattern
900 @option{--program-transform-name='s/^gcc$/myowngcc/; s/^g++$/gspecial++/'}
901 to achieve this effect.
903 All three options can be combined and used together, resulting in more
904 complex conversion patterns. As a basic rule, @var{prefix} (and
905 @var{suffix}) are prepended (appended) before further transformations
906 can happen with a special transformation script @var{pattern}.
908 As currently implemented, this option only takes effect for native
909 builds; cross compiler binaries' names are not transformed even when a
910 transformation is explicitly asked for by one of these options.
912 For native builds, some of the installed programs are also installed
913 with the target alias in front of their name, as in
914 @samp{i686-pc-linux-gnu-gcc}. All of the above transformations happen
915 before the target alias is prepended to the name---so, specifying
916 @option{--program-prefix=foo-} and @option{program-suffix=-3.1}, the
917 resulting binary would be installed as
918 @file{/usr/local/bin/i686-pc-linux-gnu-foo-gcc-3.1}.
920 As a last shortcoming, none of the installed Ada programs are
921 transformed yet, which will be fixed in some time.
923 @item --with-local-prefix=@var{dirname}
925 installation directory for local include files. The default is
926 @file{/usr/local}. Specify this option if you want the compiler to
927 search directory @file{@var{dirname}/include} for locally installed
928 header files @emph{instead} of @file{/usr/local/include}.
930 You should specify @option{--with-local-prefix} @strong{only} if your
931 site has a different convention (not @file{/usr/local}) for where to put
934 The default value for @option{--with-local-prefix} is @file{/usr/local}
935 regardless of the value of @option{--prefix}. Specifying
936 @option{--prefix} has no effect on which directory GCC searches for
937 local header files. This may seem counterintuitive, but actually it is
940 The purpose of @option{--prefix} is to specify where to @emph{install
941 GCC}. The local header files in @file{/usr/local/include}---if you put
942 any in that directory---are not part of GCC@. They are part of other
943 programs---perhaps many others. (GCC installs its own header files in
944 another directory which is based on the @option{--prefix} value.)
946 Both the local-prefix include directory and the GCC-prefix include
947 directory are part of GCC's ``system include'' directories. Although these
948 two directories are not fixed, they need to be searched in the proper
949 order for the correct processing of the include_next directive. The
950 local-prefix include directory is searched before the GCC-prefix
951 include directory. Another characteristic of system include directories
952 is that pedantic warnings are turned off for headers in these directories.
954 Some autoconf macros add @option{-I @var{directory}} options to the
955 compiler command line, to ensure that directories containing installed
956 packages' headers are searched. When @var{directory} is one of GCC's
957 system include directories, GCC will ignore the option so that system
958 directories continue to be processed in the correct order. This
959 may result in a search order different from what was specified but the
960 directory will still be searched.
962 GCC automatically searches for ordinary libraries using
963 @env{GCC_EXEC_PREFIX}. Thus, when the same installation prefix is
964 used for both GCC and packages, GCC will automatically search for
965 both headers and libraries. This provides a configuration that is
966 easy to use. GCC behaves in a manner similar to that when it is
967 installed as a system compiler in @file{/usr}.
969 Sites that need to install multiple versions of GCC may not want to
970 use the above simple configuration. It is possible to use the
971 @option{--program-prefix}, @option{--program-suffix} and
972 @option{--program-transform-name} options to install multiple versions
973 into a single directory, but it may be simpler to use different prefixes
974 and the @option{--with-local-prefix} option to specify the location of the
975 site-specific files for each version. It will then be necessary for
976 users to specify explicitly the location of local site libraries
977 (e.g., with @env{LIBRARY_PATH}).
979 The same value can be used for both @option{--with-local-prefix} and
980 @option{--prefix} provided it is not @file{/usr}. This can be used
981 to avoid the default search of @file{/usr/local/include}.
983 @strong{Do not} specify @file{/usr} as the @option{--with-local-prefix}!
984 The directory you use for @option{--with-local-prefix} @strong{must not}
985 contain any of the system's standard header files. If it did contain
986 them, certain programs would be miscompiled (including GNU Emacs, on
987 certain targets), because this would override and nullify the header
988 file corrections made by the @command{fixincludes} script.
990 Indications are that people who use this option use it based on mistaken
991 ideas of what it is for. People use it as if it specified where to
992 install part of GCC@. Perhaps they make this assumption because
993 installing GCC creates the directory.
995 @item --with-gcc-major-version-only
996 Specifies that GCC should use only the major number rather than
997 @var{major}.@var{minor}.@var{patchlevel} in filesystem paths.
999 @item --with-native-system-header-dir=@var{dirname}
1000 Specifies that @var{dirname} is the directory that contains native system
1001 header files, rather than @file{/usr/include}. This option is most useful
1002 if you are creating a compiler that should be isolated from the system
1003 as much as possible. It is most commonly used with the
1004 @option{--with-sysroot} option and will cause GCC to search
1005 @var{dirname} inside the system root specified by that option.
1007 @item --enable-shared[=@var{package}[,@dots{}]]
1008 Build shared versions of libraries, if shared libraries are supported on
1009 the target platform. Unlike GCC 2.95.x and earlier, shared libraries
1010 are enabled by default on all platforms that support shared libraries.
1012 If a list of packages is given as an argument, build shared libraries
1013 only for the listed packages. For other packages, only static libraries
1014 will be built. Package names currently recognized in the GCC tree are
1015 @samp{libgcc} (also known as @samp{gcc}), @samp{libstdc++} (not
1016 @samp{libstdc++-v3}), @samp{libffi}, @samp{zlib}, @samp{boehm-gc},
1017 @samp{ada}, @samp{libada}, @samp{libgo}, @samp{libobjc}, and @samp{libphobos}.
1018 Note @samp{libiberty} does not support shared libraries at all.
1020 Use @option{--disable-shared} to build only static libraries. Note that
1021 @option{--disable-shared} does not accept a list of package names as
1022 argument, only @option{--enable-shared} does.
1024 Contrast with @option{--enable-host-shared}, which affects @emph{host}
1027 @item --enable-host-shared
1028 Specify that the @emph{host} code should be built into position-independent
1029 machine code (with -fPIC), allowing it to be used within shared libraries,
1030 but yielding a slightly slower compiler.
1032 This option is required when building the libgccjit.so library.
1034 Contrast with @option{--enable-shared}, which affects @emph{target}
1037 @item @anchor{with-gnu-as}--with-gnu-as
1038 Specify that the compiler should assume that the
1039 assembler it finds is the GNU assembler. However, this does not modify
1040 the rules to find an assembler and will result in confusion if the
1041 assembler found is not actually the GNU assembler. (Confusion may also
1042 result if the compiler finds the GNU assembler but has not been
1043 configured with @option{--with-gnu-as}.) If you have more than one
1044 assembler installed on your system, you may want to use this option in
1045 connection with @option{--with-as=@var{pathname}} or
1046 @option{--with-build-time-tools=@var{pathname}}.
1048 The following systems are the only ones where it makes a difference
1049 whether you use the GNU assembler. On any other system,
1050 @option{--with-gnu-as} has no effect.
1053 @item @samp{hppa1.0-@var{any}-@var{any}}
1054 @item @samp{hppa1.1-@var{any}-@var{any}}
1055 @item @samp{sparc-sun-solaris2.@var{any}}
1056 @item @samp{sparc64-@var{any}-solaris2.@var{any}}
1059 @item @anchor{with-as}--with-as=@var{pathname}
1060 Specify that the compiler should use the assembler pointed to by
1061 @var{pathname}, rather than the one found by the standard rules to find
1062 an assembler, which are:
1065 Unless GCC is being built with a cross compiler, check the
1066 @file{@var{libexec}/gcc/@var{target}/@var{version}} directory.
1067 @var{libexec} defaults to @file{@var{exec-prefix}/libexec};
1068 @var{exec-prefix} defaults to @var{prefix}, which
1069 defaults to @file{/usr/local} unless overridden by the
1070 @option{--prefix=@var{pathname}} switch described above. @var{target}
1071 is the target system triple, such as @samp{sparc-sun-solaris2.7}, and
1072 @var{version} denotes the GCC version, such as 3.0.
1075 If the target system is the same that you are building on, check
1076 operating system specific directories (e.g.@: @file{/usr/ccs/bin} on
1080 Check in the @env{PATH} for a tool whose name is prefixed by the
1081 target system triple.
1084 Check in the @env{PATH} for a tool whose name is not prefixed by the
1085 target system triple, if the host and target system triple are
1086 the same (in other words, we use a host tool if it can be used for
1087 the target as well).
1090 You may want to use @option{--with-as} if no assembler
1091 is installed in the directories listed above, or if you have multiple
1092 assemblers installed and want to choose one that is not found by the
1095 @item @anchor{with-gnu-ld}--with-gnu-ld
1096 Same as @uref{#with-gnu-as,,@option{--with-gnu-as}}
1099 @item --with-ld=@var{pathname}
1100 Same as @uref{#with-as,,@option{--with-as}}
1103 @item --with-dsymutil=@var{pathname}
1104 Same as @uref{#with-as,,@option{--with-as}}
1105 but for the debug linker (only used on Darwin platforms so far).
1107 @item --with-tls=@var{dialect}
1108 Specify the default TLS dialect, for systems were there is a choice.
1109 For ARM targets, possible values for @var{dialect} are @code{gnu} or
1110 @code{gnu2}, which select between the original GNU dialect and the GNU TLS
1111 descriptor-based dialect.
1113 @item --enable-multiarch
1114 Specify whether to enable or disable multiarch support. The default is
1115 to check for glibc start files in a multiarch location, and enable it
1116 if the files are found. The auto detection is enabled for native builds,
1117 and for cross builds configured with @option{--with-sysroot}, and without
1118 @option{--with-native-system-header-dir}.
1119 More documentation about multiarch can be found at
1120 @uref{https://wiki.debian.org/Multiarch}.
1122 @item --enable-sjlj-exceptions
1123 Force use of the @code{setjmp}/@code{longjmp}-based scheme for exceptions.
1124 @samp{configure} ordinarily picks the correct value based on the platform.
1125 Only use this option if you are sure you need a different setting.
1127 @item --enable-vtable-verify
1128 Specify whether to enable or disable the vtable verification feature.
1129 Enabling this feature causes libstdc++ to be built with its virtual calls
1130 in verifiable mode. This means that, when linked with libvtv, every
1131 virtual call in libstdc++ will verify the vtable pointer through which the
1132 call will be made before actually making the call. If not linked with libvtv,
1133 the verifier will call stub functions (in libstdc++ itself) and do nothing.
1134 If vtable verification is disabled, then libstdc++ is not built with its
1135 virtual calls in verifiable mode at all. However the libvtv library will
1136 still be built (see @option{--disable-libvtv} to turn off building libvtv).
1137 @option{--disable-vtable-verify} is the default.
1139 @item --disable-gcov
1140 Specify that the run-time library used for coverage analysis
1141 and associated host tools should not be built.
1143 @item --disable-multilib
1144 Specify that multiple target
1145 libraries to support different target variants, calling
1146 conventions, etc.@: should not be built. The default is to build a
1147 predefined set of them.
1149 Some targets provide finer-grained control over which multilibs are built
1150 (e.g., @option{--disable-softfloat}):
1153 fpu, 26bit, underscore, interwork, biendian, nofmult.
1156 softfloat, m68881, m68000, m68020.
1159 single-float, biendian, softfloat.
1164 @item powerpc*-*-*, rs6000*-*-*
1165 aix64, pthread, softfloat, powercpu, powerpccpu, powerpcos, biendian,
1170 @item --with-multilib-list=@var{list}
1171 @itemx --without-multilib-list
1172 Specify what multilibs to build. @var{list} is a comma separated list of
1173 values, possibly consisting of a single value. Currently only implemented
1174 for aarch64*-*-*, arm*-*-*, loongarch64-*-*, riscv*-*-*, sh*-*-* and
1175 x86-64-*-linux*. The accepted values and meaning for each target is given
1180 @var{list} is a comma separated list of @code{ilp32}, and @code{lp64}
1181 to enable ILP32 and LP64 run-time libraries, respectively. If
1182 @var{list} is empty, then there will be no multilibs and only the
1183 default run-time library will be built. If @var{list} is
1184 @code{default} or --with-multilib-list= is not specified, then the
1185 default set of libraries is selected based on the value of
1189 @var{list} is a comma separated list of @code{aprofile} and
1190 @code{rmprofile} to build multilibs for A or R and M architecture
1191 profiles respectively. Note that, due to some limitation of the current
1192 multilib framework, using the combined @code{aprofile,rmprofile}
1193 multilibs selects in some cases a less optimal multilib than when using
1194 the multilib profile for the architecture targetted. The special value
1195 @code{default} is also accepted and is equivalent to omitting the
1196 option, i.e., only the default run-time library will be enabled.
1198 @var{list} may instead contain @code{@@name}, to use the multilib
1199 configuration Makefile fragment @file{name} in @file{gcc/config/arm} in
1200 the source tree (it is part of the corresponding sources, after all).
1201 It is recommended, but not required, that files used for this purpose to
1202 be named starting with @file{t-ml-}, to make their intended purpose
1203 self-evident, in line with GCC conventions. Such files enable custom,
1204 user-chosen multilib lists to be configured. Whether multiple such
1205 files can be used together depends on the contents of the supplied
1206 files. See @file{gcc/config/arm/t-multilib} and its supplementary
1207 @file{gcc/config/arm/t-*profile} files for an example of what such
1208 Makefile fragments might look like for this version of GCC. The macros
1209 expected to be defined in these fragments are not stable across GCC
1210 releases, so make sure they define the @code{MULTILIB}-related macros
1211 expected by the version of GCC you are building.
1213 @xref{Target Fragment,, Target Makefile Fragments, gccint, GNU Compiler
1214 Collection (GCC) Internals}.
1217 See ``Target Makefile Fragments'' in the internals manual.
1220 The table below gives the combination of ISAs, architectures, FPUs and
1221 floating-point ABIs for which multilibs are built for each predefined
1222 profile. The union of these options is considered when specifying both
1223 @code{aprofile} and @code{rmprofile}.
1225 @multitable @columnfractions .15 .28 .30
1226 @item Option @tab aprofile @tab rmprofile
1228 @tab @code{-marm} and @code{-mthumb}
1230 @item Architectures@*@*@*@*@*@*
1231 @tab default architecture@*
1232 @code{-march=armv7-a}@*
1233 @code{-march=armv7ve}@*
1234 @code{-march=armv8-a}@*@*@*
1235 @tab default architecture@*
1236 @code{-march=armv6s-m}@*
1237 @code{-march=armv7-m}@*
1238 @code{-march=armv7e-m}@*
1239 @code{-march=armv8-m.base}@*
1240 @code{-march=armv8-m.main}@*
1242 @item FPUs@*@*@*@*@*
1244 @code{-mfpu=vfpv3-d16}@*
1246 @code{-mfpu=vfpv4-d16}@*
1247 @code{-mfpu=neon-vfpv4}@*
1248 @code{-mfpu=neon-fp-armv8}
1250 @code{-mfpu=vfpv3-d16}@*
1251 @code{-mfpu=fpv4-sp-d16}@*
1252 @code{-mfpu=fpv5-sp-d16}@*
1253 @code{-mfpu=fpv5-d16}@*
1254 @item floating-point@/ ABIs@*@*
1255 @tab @code{-mfloat-abi=soft}@*
1256 @code{-mfloat-abi=softfp}@*
1257 @code{-mfloat-abi=hard}
1258 @tab @code{-mfloat-abi=soft}@*
1259 @code{-mfloat-abi=softfp}@*
1260 @code{-mfloat-abi=hard}
1263 @item loongarch*-*-*
1264 @var{list} is a comma-separated list of the following ABI identifiers:
1265 @code{lp64d[/base]} @code{lp64f[/base]} @code{lp64d[/base]}, where the
1266 @code{/base} suffix may be omitted, to enable their respective run-time
1267 libraries. If @var{list} is empty or @code{default},
1268 or if @option{--with-multilib-list} is not specified, then the default ABI
1269 as specified by @option{--with-abi} or implied by @option{--target} is selected.
1272 @var{list} is a single ABI name. The target architecture must be either
1273 @code{rv32gc} or @code{rv64gc}. This will build a single multilib for the
1274 specified architecture and ABI pair. If @code{--with-multilib-list} is not
1275 given, then a default set of multilibs is selected based on the value of
1276 @option{--target}. This is usually a large set of multilibs.
1279 @var{list} is a comma separated list of CPU names. These must be of the
1280 form @code{sh*} or @code{m*} (in which case they match the compiler option
1281 for that processor). The list should not contain any endian options -
1282 these are handled by @option{--with-endian}.
1284 If @var{list} is empty, then there will be no multilibs for extra
1285 processors. The multilib for the secondary endian remains enabled.
1287 As a special case, if an entry in the list starts with a @code{!}
1288 (exclamation point), then it is added to the list of excluded multilibs.
1289 Entries of this sort should be compatible with @samp{MULTILIB_EXCLUDES}
1290 (once the leading @code{!} has been stripped).
1292 If @option{--with-multilib-list} is not given, then a default set of
1293 multilibs is selected based on the value of @option{--target}. This is
1294 usually the complete set of libraries, but some targets imply a more
1297 Example 1: to configure a compiler for SH4A only, but supporting both
1298 endians, with little endian being the default:
1300 --with-cpu=sh4a --with-endian=little,big --with-multilib-list=
1303 Example 2: to configure a compiler for both SH4A and SH4AL-DSP, but with
1304 only little endian SH4AL:
1306 --with-cpu=sh4a --with-endian=little,big \
1307 --with-multilib-list=sh4al,!mb/m4al
1310 @item x86-64-*-linux*
1311 @var{list} is a comma separated list of @code{m32}, @code{m64} and
1312 @code{mx32} to enable 32-bit, 64-bit and x32 run-time libraries,
1313 respectively. If @var{list} is empty, then there will be no multilibs
1314 and only the default run-time library will be enabled.
1316 If @option{--with-multilib-list} is not given, then only 32-bit and
1317 64-bit run-time libraries will be enabled.
1320 @item --with-multilib-generator=@var{config}
1321 Specify what multilibs to build. @var{config} is a semicolon separated list of
1322 values, possibly consisting of a single value. Currently only implemented
1323 for riscv*-*-elf*. The accepted values and meanings are given below.
1326 Every config is constructed with four components: architecture string, ABI,
1327 reuse rule with architecture string and reuse rule with sub-extension.
1329 Example 1: Add multi-lib suppport for rv32i with ilp32.
1334 Example 2: Add multi-lib suppport for rv32i with ilp32 and rv32imafd with ilp32.
1336 rv32i-ilp32--;rv32imafd-ilp32--
1339 Example 3: Add multi-lib suppport for rv32i with ilp32; rv32im with ilp32 and
1340 rv32ic with ilp32 will reuse this multi-lib set.
1342 rv32i-ilp32-rv32im-c
1345 Example 4: Add multi-lib suppport for rv64ima with lp64; rv64imaf with lp64,
1346 rv64imac with lp64 and rv64imafc with lp64 will reuse this multi-lib set.
1348 rv64ima-lp64--f,c,fc
1351 @option{--with-multilib-generator} have an optional configuration argument
1352 @option{--cmodel=val} for code model, this option will expand with other
1353 config options, @var{val} is a comma separated list of possible code model,
1354 currently we support medlow and medany.
1356 Example 5: Add multi-lib suppport for rv64ima with lp64; rv64ima with lp64 and
1359 rv64ima-lp64--;--cmodel=medlow
1362 Example 6: Add multi-lib suppport for rv64ima with lp64; rv64ima with lp64 and
1363 medlow code model; rv64ima with lp64 and medany code model
1365 rv64ima-lp64--;--cmodel=medlow,medany
1368 @item --with-endian=@var{endians}
1369 Specify what endians to use.
1370 Currently only implemented for sh*-*-*.
1372 @var{endians} may be one of the following:
1375 Use big endian exclusively.
1377 Use little endian exclusively.
1379 Use big endian by default. Provide a multilib for little endian.
1381 Use little endian by default. Provide a multilib for big endian.
1384 @item --enable-threads
1385 Specify that the target
1386 supports threads. This affects the Objective-C compiler and runtime
1387 library, and exception handling for other languages like C++.
1388 On some systems, this is the default.
1390 In general, the best (and, in many cases, the only known) threading
1391 model available will be configured for use. Beware that on some
1392 systems, GCC has not been taught what threading models are generally
1393 available for the system. In this case, @option{--enable-threads} is an
1394 alias for @option{--enable-threads=single}.
1396 @item --disable-threads
1397 Specify that threading support should be disabled for the system.
1398 This is an alias for @option{--enable-threads=single}.
1400 @item --enable-threads=@var{lib}
1402 @var{lib} is the thread support library. This affects the Objective-C
1403 compiler and runtime library, and exception handling for other languages
1404 like C++. The possibilities for @var{lib} are:
1412 LynxOS thread support.
1414 MIPS SDE thread support.
1416 This is an alias for @samp{single}.
1418 Generic POSIX/Unix98 thread support.
1420 RTEMS thread support.
1422 Disable thread support, should work for all platforms.
1426 VxWorks thread support.
1428 Microsoft Win32 API thread support.
1432 Specify that the target supports TLS (Thread Local Storage). Usually
1433 configure can correctly determine if TLS is supported. In cases where
1434 it guesses incorrectly, TLS can be explicitly enabled or disabled with
1435 @option{--enable-tls} or @option{--disable-tls}. This can happen if
1436 the assembler supports TLS but the C library does not, or if the
1437 assumptions made by the configure test are incorrect.
1440 Specify that the target does not support TLS.
1441 This is an alias for @option{--enable-tls=no}.
1443 @item --disable-tm-clone-registry
1444 Disable TM clone registry in libgcc. It is enabled in libgcc by default.
1445 This option helps to reduce code size for embedded targets which do
1446 not use transactional memory.
1448 @item --with-cpu=@var{cpu}
1449 @itemx --with-cpu-32=@var{cpu}
1450 @itemx --with-cpu-64=@var{cpu}
1451 Specify which cpu variant the compiler should generate code for by default.
1452 @var{cpu} will be used as the default value of the @option{-mcpu=} switch.
1453 This option is only supported on some targets, including ARC, ARM, i386, M68k,
1454 PowerPC, and SPARC@. It is mandatory for ARC@. The @option{--with-cpu-32} and
1455 @option{--with-cpu-64} options specify separate default CPUs for
1456 32-bit and 64-bit modes; these options are only supported for aarch64, i386,
1457 x86-64, PowerPC, and SPARC@.
1459 @item --with-schedule=@var{cpu}
1460 @itemx --with-arch=@var{cpu}
1461 @itemx --with-arch-32=@var{cpu}
1462 @itemx --with-arch-64=@var{cpu}
1463 @itemx --with-tune=@var{cpu}
1464 @itemx --with-tune-32=@var{cpu}
1465 @itemx --with-tune-64=@var{cpu}
1466 @itemx --with-abi=@var{abi}
1467 @itemx --with-fpu=@var{type}
1468 @itemx --with-float=@var{type}
1469 These configure options provide default values for the @option{-mschedule=},
1470 @option{-march=}, @option{-mtune=}, @option{-mabi=}, and @option{-mfpu=}
1471 options and for @option{-mhard-float} or @option{-msoft-float}. As with
1472 @option{--with-cpu}, which switches will be accepted and acceptable values
1473 of the arguments depend on the target.
1475 @item --with-mode=@var{mode}
1476 Specify if the compiler should default to @option{-marm} or @option{-mthumb}.
1477 This option is only supported on ARM targets.
1479 @item --with-stack-offset=@var{num}
1480 This option sets the default for the -mstack-offset=@var{num} option,
1481 and will thus generally also control the setting of this option for
1482 libraries. This option is only supported on Epiphany targets.
1484 @item --with-fpmath=@var{isa}
1485 This options sets @option{-mfpmath=sse} by default and specifies the default
1486 ISA for floating-point arithmetics. You can select either @samp{sse} which
1487 enables @option{-msse2} or @samp{avx} which enables @option{-mavx} by default.
1488 This option is only supported on i386 and x86-64 targets.
1490 @item --with-fp-32=@var{mode}
1491 On MIPS targets, set the default value for the @option{-mfp} option when using
1492 the o32 ABI. The possibilities for @var{mode} are:
1495 Use the o32 FP32 ABI extension, as with the @option{-mfp32} command-line
1498 Use the o32 FPXX ABI extension, as with the @option{-mfpxx} command-line
1501 Use the o32 FP64 ABI extension, as with the @option{-mfp64} command-line
1504 In the absence of this configuration option the default is to use the o32
1507 @item --with-odd-spreg-32
1508 On MIPS targets, set the @option{-modd-spreg} option by default when using
1511 @item --without-odd-spreg-32
1512 On MIPS targets, set the @option{-mno-odd-spreg} option by default when using
1513 the o32 ABI. This is normally used in conjunction with
1514 @option{--with-fp-32=64} in order to target the o32 FP64A ABI extension.
1516 @item --with-nan=@var{encoding}
1517 On MIPS targets, set the default encoding convention to use for the
1518 special not-a-number (NaN) IEEE 754 floating-point data. The
1519 possibilities for @var{encoding} are:
1522 Use the legacy encoding, as with the @option{-mnan=legacy} command-line
1525 Use the 754-2008 encoding, as with the @option{-mnan=2008} command-line
1528 To use this configuration option you must have an assembler version
1529 installed that supports the @option{-mnan=} command-line option too.
1530 In the absence of this configuration option the default convention is
1531 the legacy encoding, as when neither of the @option{-mnan=2008} and
1532 @option{-mnan=legacy} command-line options has been used.
1534 @item --with-divide=@var{type}
1535 Specify how the compiler should generate code for checking for
1536 division by zero. This option is only supported on the MIPS target.
1537 The possibilities for @var{type} are:
1540 Division by zero checks use conditional traps (this is the default on
1541 systems that support conditional traps).
1543 Division by zero checks use the break instruction.
1546 @c If you make --with-llsc the default for additional targets,
1547 @c update the --with-llsc description in the MIPS section below.
1550 On MIPS targets, make @option{-mllsc} the default when no
1551 @option{-mno-llsc} option is passed. This is the default for
1552 Linux-based targets, as the kernel will emulate them if the ISA does
1555 @item --without-llsc
1556 On MIPS targets, make @option{-mno-llsc} the default when no
1557 @option{-mllsc} option is passed.
1560 On MIPS targets, make @option{-msynci} the default when no
1561 @option{-mno-synci} option is passed.
1563 @item --without-synci
1564 On MIPS targets, make @option{-mno-synci} the default when no
1565 @option{-msynci} option is passed. This is the default.
1567 @item --with-lxc1-sxc1
1568 On MIPS targets, make @option{-mlxc1-sxc1} the default when no
1569 @option{-mno-lxc1-sxc1} option is passed. This is the default.
1571 @item --without-lxc1-sxc1
1572 On MIPS targets, make @option{-mno-lxc1-sxc1} the default when no
1573 @option{-mlxc1-sxc1} option is passed. The indexed load/store
1574 instructions are not directly a problem but can lead to unexpected
1575 behaviour when deployed in an application intended for a 32-bit address
1576 space but run on a 64-bit processor. The issue is seen because all
1577 known MIPS 64-bit Linux kernels execute o32 and n32 applications
1578 with 64-bit addressing enabled which affects the overflow behaviour
1579 of the indexed addressing mode. GCC will assume that ordinary
1580 32-bit arithmetic overflow behaviour is the same whether performed
1581 as an @code{addu} instruction or as part of the address calculation
1582 in @code{lwxc1} type instructions. This assumption holds true in a
1583 pure 32-bit environment and can hold true in a 64-bit environment if
1584 the address space is accurately set to be 32-bit for o32 and n32.
1587 On MIPS targets, make @option{-mmadd4} the default when no
1588 @option{-mno-madd4} option is passed. This is the default.
1590 @item --without-madd4
1591 On MIPS targets, make @option{-mno-madd4} the default when no
1592 @option{-mmadd4} option is passed. The @code{madd4} instruction
1593 family can be problematic when targeting a combination of cores that
1594 implement these instructions differently. There are two known cores
1595 that implement these as fused operations instead of unfused (where
1596 unfused is normally expected). Disabling these instructions is the
1597 only way to ensure compatible code is generated; this will incur
1598 a performance penalty.
1600 @item --with-mips-plt
1601 On MIPS targets, make use of copy relocations and PLTs.
1602 These features are extensions to the traditional
1603 SVR4-based MIPS ABIs and require support from GNU binutils
1604 and the runtime C library.
1606 @item --with-stack-clash-protection-guard-size=@var{size}
1607 On certain targets this option sets the default stack clash protection guard
1608 size as a power of two in bytes. On AArch64 @var{size} is required to be either
1609 12 (4KB) or 16 (64KB).
1611 @item --with-isa-spec=@var{ISA-spec-string}
1612 On RISC-V targets specify the default version of the RISC-V Unprivileged
1613 (formerly User-Level) ISA specification to produce code conforming to.
1614 The possibilities for @var{ISA-spec-string} are:
1617 Produce code conforming to version 2.2.
1619 Produce code conforming to version 20190608.
1621 Produce code conforming to version 20191213.
1623 In the absence of this configuration option the default version is 20191213.
1625 @item --enable-__cxa_atexit
1626 Define if you want to use __cxa_atexit, rather than atexit, to
1627 register C++ destructors for local statics and global objects.
1628 This is essential for fully standards-compliant handling of
1629 destructors, but requires __cxa_atexit in libc. This option is currently
1630 only available on systems with GNU libc. When enabled, this will cause
1631 @option{-fuse-cxa-atexit} to be passed by default.
1633 @item --enable-gnu-indirect-function
1634 Define if you want to enable the @code{ifunc} attribute. This option is
1635 currently only available on systems with GNU libc on certain targets.
1637 @item --enable-target-optspace
1639 libraries should be optimized for code space instead of code speed.
1640 This is the default for the m32r platform.
1642 @item --with-cpp-install-dir=@var{dirname}
1643 Specify that the user visible @command{cpp} program should be installed
1644 in @file{@var{prefix}/@var{dirname}/cpp}, in addition to @var{bindir}.
1646 @item --enable-comdat
1647 Enable COMDAT group support. This is primarily used to override the
1648 automatically detected value.
1650 @item --enable-initfini-array
1651 Force the use of sections @code{.init_array} and @code{.fini_array}
1652 (instead of @code{.init} and @code{.fini}) for constructors and
1653 destructors. Option @option{--disable-initfini-array} has the
1654 opposite effect. If neither option is specified, the configure script
1655 will try to guess whether the @code{.init_array} and
1656 @code{.fini_array} sections are supported and, if they are, use them.
1658 @item --enable-link-mutex
1659 When building GCC, use a mutex to avoid linking the compilers for
1660 multiple languages at the same time, to avoid thrashing on build
1661 systems with limited free memory. The default is not to use such a mutex.
1663 @item --enable-link-serialization
1664 When building GCC, use make dependencies to serialize linking the compilers for
1665 multiple languages, to avoid thrashing on build
1666 systems with limited free memory. The default is not to add such
1667 dependencies and thus with parallel make potentially link different
1668 compilers concurrently. If the argument is a positive integer, allow
1669 that number of concurrent link processes for the large binaries.
1671 @item --enable-maintainer-mode
1672 The build rules that regenerate the Autoconf and Automake output files as
1673 well as the GCC master message catalog @file{gcc.pot} are normally
1674 disabled. This is because it can only be rebuilt if the complete source
1675 tree is present. If you have changed the sources and want to rebuild the
1676 catalog, configuring with @option{--enable-maintainer-mode} will enable
1677 this. Note that you need a recent version of the @code{gettext} tools
1680 @item --disable-bootstrap
1681 For a native build, the default configuration is to perform
1682 a 3-stage bootstrap of the compiler when @samp{make} is invoked,
1683 testing that GCC can compile itself correctly. If you want to disable
1684 this process, you can configure with @option{--disable-bootstrap}.
1686 @item --enable-bootstrap
1687 In special cases, you may want to perform a 3-stage build
1688 even if the target and host triplets are different.
1689 This is possible when the host can run code compiled for
1690 the target (e.g.@: host is i686-linux, target is i486-linux).
1691 Starting from GCC 4.2, to do this you have to configure explicitly
1692 with @option{--enable-bootstrap}.
1694 @item --enable-generated-files-in-srcdir
1695 Neither the .c and .h files that are generated from Bison and flex nor the
1696 info manuals and man pages that are built from the .texi files are present
1697 in the repository development tree. When building GCC from that development tree,
1698 or from one of our snapshots, those generated files are placed in your
1699 build directory, which allows for the source to be in a readonly
1702 If you configure with @option{--enable-generated-files-in-srcdir} then those
1703 generated files will go into the source directory. This is mainly intended
1704 for generating release or prerelease tarballs of the GCC sources, since it
1705 is not a requirement that the users of source releases to have flex, Bison,
1708 @item --enable-version-specific-runtime-libs
1710 that runtime libraries should be installed in the compiler specific
1711 subdirectory (@file{@var{libdir}/gcc}) rather than the usual places. In
1712 addition, @samp{libstdc++}'s include files will be installed into
1713 @file{@var{libdir}} unless you overruled it by using
1714 @option{--with-gxx-include-dir=@var{dirname}}. Using this option is
1715 particularly useful if you intend to use several versions of GCC in
1716 parallel. The default is @samp{yes} for @samp{libada}, and @samp{no} for
1717 the remaining libraries.
1719 @item @anchor{WithAixSoname}--with-aix-soname=@samp{aix}, @samp{svr4} or @samp{both}
1720 Traditional AIX shared library versioning (versioned @code{Shared Object}
1721 files as members of unversioned @code{Archive Library} files named
1722 @samp{lib.a}) causes numerous headaches for package managers. However,
1723 @code{Import Files} as members of @code{Archive Library} files allow for
1724 @strong{filename-based versioning} of shared libraries as seen on Linux/SVR4,
1725 where this is called the "SONAME". But as they prevent static linking,
1726 @code{Import Files} may be used with @code{Runtime Linking} only, where the
1727 linker does search for @samp{libNAME.so} before @samp{libNAME.a} library
1728 filenames with the @samp{-lNAME} linker flag.
1730 @anchor{AixLdCommand}For detailed information please refer to the AIX
1731 @uref{https://www.ibm.com/support/knowledgecenter/search/%22the%20ld%20command%2C%20also%20called%20the%20linkage%20editor%20or%20binder%22,,ld
1734 As long as shared library creation is enabled, upon:
1736 @item --with-aix-soname=aix
1737 @item --with-aix-soname=both
1738 A (traditional AIX) @code{Shared Archive Library} file is created:
1740 @item using the @samp{libNAME.a} filename scheme
1741 @item with the @code{Shared Object} file as archive member named
1742 @samp{libNAME.so.V} (except for @samp{libgcc_s}, where the @code{Shared
1743 Object} file is named @samp{shr.o} for backwards compatibility), which
1745 @item is used for runtime loading from inside the @samp{libNAME.a} file
1746 @item is used for dynamic loading via
1747 @code{dlopen("libNAME.a(libNAME.so.V)", RTLD_MEMBER)}
1748 @item is used for shared linking
1749 @item is used for static linking, so no separate @code{Static Archive
1750 Library} file is needed
1753 @item --with-aix-soname=both
1754 @item --with-aix-soname=svr4
1755 A (second) @code{Shared Archive Library} file is created:
1757 @item using the @samp{libNAME.so.V} filename scheme
1758 @item with the @code{Shared Object} file as archive member named
1761 @item is created with the @code{-G linker flag}
1762 @item has the @code{F_LOADONLY} flag set
1763 @item is used for runtime loading from inside the @samp{libNAME.so.V} file
1764 @item is used for dynamic loading via @code{dlopen("libNAME.so.V(shr.o)",
1767 @item with the @code{Import File} as archive member named @samp{shr.imp},
1770 @item refers to @samp{libNAME.so.V(shr.o)} as the "SONAME", to be recorded
1771 in the @code{Loader Section} of subsequent binaries
1772 @item indicates whether @samp{libNAME.so.V(shr.o)} is 32 or 64 bit
1773 @item lists all the public symbols exported by @samp{lib.so.V(shr.o)},
1774 eventually decorated with the @code{@samp{weak} Keyword}
1775 @item is necessary for shared linking against @samp{lib.so.V(shr.o)}
1778 A symbolic link using the @samp{libNAME.so} filename scheme is created:
1780 @item pointing to the @samp{libNAME.so.V} @code{Shared Archive Library} file
1781 @item to permit the @code{ld Command} to find @samp{lib.so.V(shr.imp)} via
1782 the @samp{-lNAME} argument (requires @code{Runtime Linking} to be enabled)
1783 @item to permit dynamic loading of @samp{lib.so.V(shr.o)} without the need
1784 to specify the version number via @code{dlopen("libNAME.so(shr.o)",
1789 As long as static library creation is enabled, upon:
1791 @item --with-aix-soname=svr4
1792 A @code{Static Archive Library} is created:
1794 @item using the @samp{libNAME.a} filename scheme
1795 @item with all the @code{Static Object} files as archive members, which
1797 @item are used for static linking
1802 While the aix-soname=@samp{svr4} option does not create @code{Shared Object}
1803 files as members of unversioned @code{Archive Library} files any more, package
1804 managers still are responsible to
1805 @uref{./specific.html#TransferAixShobj,,transfer} @code{Shared Object} files
1806 found as member of a previously installed unversioned @code{Archive Library}
1807 file into the newly installed @code{Archive Library} file with the same
1810 @emph{WARNING:} Creating @code{Shared Object} files with @code{Runtime Linking}
1811 enabled may bloat the TOC, eventually leading to @code{TOC overflow} errors,
1812 requiring the use of either the @option{-Wl,-bbigtoc} linker flag (seen to
1813 break with the @code{GDB} debugger) or some of the TOC-related compiler flags,
1815 @xref{RS/6000 and PowerPC Options,, RS/6000 and PowerPC Options, gcc,
1816 Using the GNU Compiler Collection (GCC)}.
1819 see ``RS/6000 and PowerPC Options'' in the main manual.
1822 @option{--with-aix-soname} is currently supported by @samp{libgcc_s} only, so
1823 this option is still experimental and not for normal use yet.
1825 Default is the traditional behavior @option{--with-aix-soname=@samp{aix}}.
1827 @item --enable-languages=@var{lang1},@var{lang2},@dots{}
1828 Specify that only a particular subset of compilers and
1829 their runtime libraries should be built. For a list of valid values for
1830 @var{langN} you can issue the following command in the
1831 @file{gcc} directory of your GCC source tree:@*
1833 grep ^language= */config-lang.in
1835 Currently, you can use any of the following:
1836 @code{all}, @code{default}, @code{ada}, @code{c}, @code{c++}, @code{d},
1837 @code{fortran}, @code{go}, @code{jit}, @code{lto}, @code{objc}, @code{obj-c++}.
1838 Building the Ada compiler has special requirements, see below.
1839 If you do not pass this flag, or specify the option @code{default}, then the
1840 default languages available in the @file{gcc} sub-tree will be configured.
1841 Ada, D, Go, Jit, and Objective-C++ are not default languages. LTO is not a
1842 default language, but is built by default because @option{--enable-lto} is
1843 enabled by default. The other languages are default languages. If
1844 @code{all} is specified, then all available languages are built. An
1845 exception is @code{jit} language, which requires
1846 @option{--enable-host-shared} to be included with @code{all}.
1848 @item --enable-stage1-languages=@var{lang1},@var{lang2},@dots{}
1849 Specify that a particular subset of compilers and their runtime
1850 libraries should be built with the system C compiler during stage 1 of
1851 the bootstrap process, rather than only in later stages with the
1852 bootstrapped C compiler. The list of valid values is the same as for
1853 @option{--enable-languages}, and the option @code{all} will select all
1854 of the languages enabled by @option{--enable-languages}. This option is
1855 primarily useful for GCC development; for instance, when a development
1856 version of the compiler cannot bootstrap due to compiler bugs, or when
1857 one is debugging front ends other than the C front end. When this
1858 option is used, one can then build the target libraries for the
1859 specified languages with the stage-1 compiler by using @command{make
1860 stage1-bubble all-target}, or run the testsuite on the stage-1 compiler
1861 for the specified languages using @command{make stage1-start check-gcc}.
1863 @item --disable-libada
1864 Specify that the run-time libraries and tools used by GNAT should not
1865 be built. This can be useful for debugging, or for compatibility with
1866 previous Ada build procedures, when it was required to explicitly
1867 do a @samp{make -C gcc gnatlib_and_tools}.
1869 @item --disable-libsanitizer
1870 Specify that the run-time libraries for the various sanitizers should
1873 @item --disable-libssp
1874 Specify that the run-time libraries for stack smashing protection
1875 should not be built or linked against. On many targets library support
1876 is provided by the C library instead.
1878 @item --disable-libquadmath
1879 Specify that the GCC quad-precision math library should not be built.
1880 On some systems, the library is required to be linkable when building
1881 the Fortran front end, unless @option{--disable-libquadmath-support}
1884 @item --disable-libquadmath-support
1885 Specify that the Fortran front end and @code{libgfortran} do not add
1886 support for @code{libquadmath} on systems supporting it.
1888 @item --disable-libgomp
1889 Specify that the GNU Offloading and Multi Processing Runtime Library
1890 should not be built.
1892 @item --disable-libvtv
1893 Specify that the run-time libraries used by vtable verification
1894 should not be built.
1897 Specify that the compiler should
1898 use DWARF 2 debugging information as the default.
1900 @item --with-advance-toolchain=@var{at}
1901 On 64-bit PowerPC Linux systems, configure the compiler to use the
1902 header files, library files, and the dynamic linker from the Advance
1903 Toolchain release @var{at} instead of the default versions that are
1904 provided by the Linux distribution. In general, this option is
1905 intended for the developers of GCC, and it is not intended for general
1908 @item --enable-targets=all
1909 @itemx --enable-targets=@var{target_list}
1910 Some GCC targets, e.g.@: powerpc64-linux, build bi-arch compilers.
1911 These are compilers that are able to generate either 64-bit or 32-bit
1912 code. Typically, the corresponding 32-bit target, e.g.@:
1913 powerpc-linux for powerpc64-linux, only generates 32-bit code. This
1914 option enables the 32-bit target to be a bi-arch compiler, which is
1915 useful when you want a bi-arch compiler that defaults to 32-bit, and
1916 you are building a bi-arch or multi-arch binutils in a combined tree.
1917 On mips-linux, this will build a tri-arch compiler (ABI o32/n32/64),
1919 Currently, this option only affects sparc-linux, powerpc-linux, x86-linux,
1920 mips-linux and s390-linux.
1922 @item --enable-default-pie
1923 Turn on @option{-fPIE} and @option{-pie} by default.
1925 @item --enable-secureplt
1926 This option enables @option{-msecure-plt} by default for powerpc-linux.
1928 @xref{RS/6000 and PowerPC Options,, RS/6000 and PowerPC Options, gcc,
1929 Using the GNU Compiler Collection (GCC)},
1932 See ``RS/6000 and PowerPC Options'' in the main manual
1935 @item --enable-default-ssp
1936 Turn on @option{-fstack-protector-strong} by default.
1939 This option enables @option{-mcld} by default for 32-bit x86 targets.
1941 @xref{i386 and x86-64 Options,, i386 and x86-64 Options, gcc,
1942 Using the GNU Compiler Collection (GCC)},
1945 See ``i386 and x86-64 Options'' in the main manual
1948 @item --enable-large-address-aware
1949 The @option{--enable-large-address-aware} option arranges for MinGW
1950 executables to be linked using the @option{--large-address-aware}
1951 option, that enables the use of more than 2GB of memory. If GCC is
1952 configured with this option, its effects can be reversed by passing the
1953 @option{-Wl,--disable-large-address-aware} option to the so-configured
1956 @item --enable-win32-registry
1957 @itemx --enable-win32-registry=@var{key}
1958 @itemx --disable-win32-registry
1959 The @option{--enable-win32-registry} option enables Microsoft Windows-hosted GCC
1960 to look up installations paths in the registry using the following key:
1963 @code{HKEY_LOCAL_MACHINE\SOFTWARE\Free Software Foundation\@var{key}}
1966 @var{key} defaults to GCC version number, and can be overridden by the
1967 @option{--enable-win32-registry=@var{key}} option. Vendors and distributors
1968 who use custom installers are encouraged to provide a different key,
1969 perhaps one comprised of vendor name and GCC version number, to
1970 avoid conflict with existing installations. This feature is enabled
1971 by default, and can be disabled by @option{--disable-win32-registry}
1972 option. This option has no effect on the other hosts.
1975 Specify that the machine does not have a floating point unit. This
1976 option only applies to @samp{m68k-sun-sunos@var{n}}. On any other
1977 system, @option{--nfp} has no effect.
1979 @item --enable-werror
1980 @itemx --disable-werror
1981 @itemx --enable-werror=yes
1982 @itemx --enable-werror=no
1983 When you specify this option, it controls whether certain files in the
1984 compiler are built with @option{-Werror} in bootstrap stage2 and later.
1985 If you don't specify it, @option{-Werror} is turned on for the main
1986 development trunk. However it defaults to off for release branches and
1987 final releases. The specific files which get @option{-Werror} are
1988 controlled by the Makefiles.
1990 @item --enable-checking
1991 @itemx --disable-checking
1992 @itemx --enable-checking=@var{list}
1993 This option controls performing internal consistency checks in the compiler.
1994 It does not change the generated code, but adds error checking of the
1995 requested complexity. This slows down the compiler and may only work
1996 properly if you are building the compiler with GCC@.
1998 When the option is not specified, the active set of checks depends on context.
1999 Namely, bootstrap stage 1 defaults to @samp{--enable-checking=yes}, builds
2000 from release branches or release archives default to
2001 @samp{--enable-checking=release}, and otherwise
2002 @samp{--enable-checking=yes,extra} is used. When the option is
2003 specified without a @var{list}, the result is the same as
2004 @samp{--enable-checking=yes}. Likewise, @samp{--disable-checking} is
2005 equivalent to @samp{--enable-checking=no}.
2007 The categories of checks available in @var{list} are @samp{yes} (most common
2008 checks @samp{assert,misc,gc,gimple,rtlflag,runtime,tree,types}), @samp{no}
2009 (no checks at all), @samp{all} (all but @samp{valgrind}), @samp{release}
2010 (cheapest checks @samp{assert,runtime}) or @samp{none} (same as @samp{no}).
2011 @samp{release} checks are always on and to disable them
2012 @samp{--disable-checking} or @samp{--enable-checking=no[,<other checks>]}
2013 must be explicitly requested. Disabling assertions makes the compiler and
2014 runtime slightly faster but increases the risk of undetected internal errors
2015 causing wrong code to be generated.
2017 Individual checks can be enabled with these flags: @samp{assert}, @samp{df},
2018 @samp{extra}, @samp{fold}, @samp{gc}, @samp{gcac}, @samp{gimple},
2019 @samp{misc}, @samp{rtl}, @samp{rtlflag}, @samp{runtime}, @samp{tree},
2020 @samp{types} and @samp{valgrind}. @samp{extra} extends @samp{misc}
2021 checking with extra checks that might affect code generation and should
2022 therefore not differ between stage1 and later stages in bootstrap.
2024 The @samp{valgrind} check requires the external @command{valgrind} simulator,
2025 available from @uref{https://valgrind.org}. The @samp{rtl} checks are
2026 expensive and the @samp{df}, @samp{gcac} and @samp{valgrind} checks are very
2029 @item --disable-stage1-checking
2030 @itemx --enable-stage1-checking
2031 @itemx --enable-stage1-checking=@var{list}
2032 This option affects only bootstrap build. If no @option{--enable-checking}
2033 option is specified the stage1 compiler is built with @samp{yes} checking
2034 enabled, otherwise the stage1 checking flags are the same as specified by
2035 @option{--enable-checking}. To build the stage1 compiler with
2036 different checking options use @option{--enable-stage1-checking}.
2037 The list of checking options is the same as for @option{--enable-checking}.
2038 If your system is too slow or too small to bootstrap a released compiler
2039 with checking for stage1 enabled, you can use @samp{--disable-stage1-checking}
2040 to disable checking for the stage1 compiler.
2042 @item --enable-coverage
2043 @itemx --enable-coverage=@var{level}
2044 With this option, the compiler is built to collect self coverage
2045 information, every time it is run. This is for internal development
2046 purposes, and only works when the compiler is being built with gcc. The
2047 @var{level} argument controls whether the compiler is built optimized or
2048 not, values are @samp{opt} and @samp{noopt}. For coverage analysis you
2049 want to disable optimization, for performance analysis you want to
2050 enable optimization. When coverage is enabled, the default level is
2051 without optimization.
2053 @item --enable-gather-detailed-mem-stats
2054 When this option is specified more detailed information on memory
2055 allocation is gathered. This information is printed when using
2056 @option{-fmem-report}.
2058 @item --enable-valgrind-annotations
2059 Mark selected memory related operations in the compiler when run under
2060 valgrind to suppress false positives.
2063 @itemx --disable-nls
2064 The @option{--enable-nls} option enables Native Language Support (NLS),
2065 which lets GCC output diagnostics in languages other than American
2066 English. Native Language Support is enabled by default if not doing a
2067 canadian cross build. The @option{--disable-nls} option disables NLS@.
2069 @item --with-included-gettext
2070 If NLS is enabled, the @option{--with-included-gettext} option causes the build
2071 procedure to prefer its copy of GNU @command{gettext}.
2073 @item --with-catgets
2074 If NLS is enabled, and if the host lacks @code{gettext} but has the
2075 inferior @code{catgets} interface, the GCC build procedure normally
2076 ignores @code{catgets} and instead uses GCC's copy of the GNU
2077 @code{gettext} library. The @option{--with-catgets} option causes the
2078 build procedure to use the host's @code{catgets} in this situation.
2080 @item --with-libiconv-prefix=@var{dir}
2081 Search for libiconv header files in @file{@var{dir}/include} and
2082 libiconv library files in @file{@var{dir}/lib}.
2084 @item --enable-obsolete
2085 Enable configuration for an obsoleted system. If you attempt to
2086 configure GCC for a system (build, host, or target) which has been
2087 obsoleted, and you do not specify this flag, configure will halt with an
2090 All support for systems which have been obsoleted in one release of GCC
2091 is removed entirely in the next major release, unless someone steps
2092 forward to maintain the port.
2094 @item --enable-decimal-float
2095 @itemx --enable-decimal-float=yes
2096 @itemx --enable-decimal-float=no
2097 @itemx --enable-decimal-float=bid
2098 @itemx --enable-decimal-float=dpd
2099 @itemx --disable-decimal-float
2100 Enable (or disable) support for the C decimal floating point extension
2101 that is in the IEEE 754-2008 standard. This is enabled by default only
2102 on PowerPC, i386, and x86_64 GNU/Linux systems. Other systems may also
2103 support it, but require the user to specifically enable it. You can
2104 optionally control which decimal floating point format is used (either
2105 @samp{bid} or @samp{dpd}). The @samp{bid} (binary integer decimal)
2106 format is default on i386 and x86_64 systems, and the @samp{dpd}
2107 (densely packed decimal) format is default on PowerPC systems.
2109 @item --enable-fixed-point
2110 @itemx --disable-fixed-point
2111 Enable (or disable) support for C fixed-point arithmetic.
2112 This option is enabled by default for some targets (such as MIPS) which
2113 have hardware-support for fixed-point operations. On other targets, you
2114 may enable this option manually.
2116 @item --with-long-double-128
2117 Specify if @code{long double} type should be 128-bit by default on selected
2118 GNU/Linux architectures. If using @code{--without-long-double-128},
2119 @code{long double} will be by default 64-bit, the same as @code{double} type.
2120 When neither of these configure options are used, the default will be
2121 128-bit @code{long double} when built against GNU C Library 2.4 and later,
2122 64-bit @code{long double} otherwise.
2124 @item --with-long-double-format=ibm
2125 @itemx --with-long-double-format=ieee
2126 Specify whether @code{long double} uses the IBM extended double format
2127 or the IEEE 128-bit floating point format on PowerPC Linux systems.
2128 This configuration switch will only work on little endian PowerPC
2129 Linux systems and on big endian 64-bit systems where the default cpu
2130 is at least power7 (i.e.@: @option{--with-cpu=power7},
2131 @option{--with-cpu=power8}, or @option{--with-cpu=power9} is used).
2133 If you use the @option{--with-long-double-64} configuration option,
2134 the @option{--with-long-double-format=ibm} and
2135 @option{--with-long-double-format=ieee} options are ignored.
2137 The default @code{long double} format is to use IBM extended double.
2138 Until all of the libraries are converted to use IEEE 128-bit floating
2139 point, it is not recommended to use
2140 @option{--with-long-double-format=ieee}.
2142 On little endian PowerPC Linux systems, if you explicitly set the
2143 @code{long double} type, it will build multilibs to allow you to
2144 select either @code{long double} format, unless you disable multilibs
2145 with the @code{--disable-multilib} option. At present,
2146 @code{long double} multilibs are not built on big endian PowerPC Linux
2147 systems. If you are building multilibs, you will need to configure
2148 the compiler using the @option{--with-system-zlib} option.
2150 If you do not set the @code{long double} type explicitly, no multilibs
2153 @item --enable-fdpic
2154 On SH Linux systems, generate ELF FDPIC code.
2156 @item --with-gmp=@var{pathname}
2157 @itemx --with-gmp-include=@var{pathname}
2158 @itemx --with-gmp-lib=@var{pathname}
2159 @itemx --with-mpfr=@var{pathname}
2160 @itemx --with-mpfr-include=@var{pathname}
2161 @itemx --with-mpfr-lib=@var{pathname}
2162 @itemx --with-mpc=@var{pathname}
2163 @itemx --with-mpc-include=@var{pathname}
2164 @itemx --with-mpc-lib=@var{pathname}
2165 If you want to build GCC but do not have the GMP library, the MPFR
2166 library and/or the MPC library installed in a standard location and
2167 do not have their sources present in the GCC source tree then you
2168 can explicitly specify the directory where they are installed
2169 (@samp{--with-gmp=@var{gmpinstalldir}},
2170 @samp{--with-mpfr=@/@var{mpfrinstalldir}},
2171 @samp{--with-mpc=@/@var{mpcinstalldir}}). The
2172 @option{--with-gmp=@/@var{gmpinstalldir}} option is shorthand for
2173 @option{--with-gmp-lib=@/@var{gmpinstalldir}/lib} and
2174 @option{--with-gmp-include=@/@var{gmpinstalldir}/include}. Likewise the
2175 @option{--with-mpfr=@/@var{mpfrinstalldir}} option is shorthand for
2176 @option{--with-mpfr-lib=@/@var{mpfrinstalldir}/lib} and
2177 @option{--with-mpfr-include=@/@var{mpfrinstalldir}/include}, also the
2178 @option{--with-mpc=@/@var{mpcinstalldir}} option is shorthand for
2179 @option{--with-mpc-lib=@/@var{mpcinstalldir}/lib} and
2180 @option{--with-mpc-include=@/@var{mpcinstalldir}/include}. If these
2181 shorthand assumptions are not correct, you can use the explicit
2182 include and lib options directly. You might also need to ensure the
2183 shared libraries can be found by the dynamic linker when building and
2184 using GCC, for example by setting the runtime shared library path
2185 variable (@env{LD_LIBRARY_PATH} on GNU/Linux and Solaris systems).
2187 These flags are applicable to the host platform only. When building
2188 a cross compiler, they will not be used to configure target libraries.
2190 @item --with-isl=@var{pathname}
2191 @itemx --with-isl-include=@var{pathname}
2192 @itemx --with-isl-lib=@var{pathname}
2193 If you do not have the isl library installed in a standard location and you
2194 want to build GCC, you can explicitly specify the directory where it is
2195 installed (@samp{--with-isl=@/@var{islinstalldir}}). The
2196 @option{--with-isl=@/@var{islinstalldir}} option is shorthand for
2197 @option{--with-isl-lib=@/@var{islinstalldir}/lib} and
2198 @option{--with-isl-include=@/@var{islinstalldir}/include}. If this
2199 shorthand assumption is not correct, you can use the explicit
2200 include and lib options directly.
2202 These flags are applicable to the host platform only. When building
2203 a cross compiler, they will not be used to configure target libraries.
2205 @item --with-stage1-ldflags=@var{flags}
2206 This option may be used to set linker flags to be used when linking
2207 stage 1 of GCC. These are also used when linking GCC if configured with
2208 @option{--disable-bootstrap}. If @option{--with-stage1-libs} is not set to a
2209 value, then the default is @samp{-static-libstdc++ -static-libgcc}, if
2212 @item --with-stage1-libs=@var{libs}
2213 This option may be used to set libraries to be used when linking stage 1
2214 of GCC. These are also used when linking GCC if configured with
2215 @option{--disable-bootstrap}.
2217 @item --with-boot-ldflags=@var{flags}
2218 This option may be used to set linker flags to be used when linking
2219 stage 2 and later when bootstrapping GCC. If --with-boot-libs
2220 is not is set to a value, then the default is
2221 @samp{-static-libstdc++ -static-libgcc}.
2223 @item --with-boot-libs=@var{libs}
2224 This option may be used to set libraries to be used when linking stage 2
2225 and later when bootstrapping GCC.
2227 @item --with-debug-prefix-map=@var{map}
2228 Convert source directory names using @option{-fdebug-prefix-map} when
2229 building runtime libraries. @samp{@var{map}} is a space-separated
2230 list of maps of the form @samp{@var{old}=@var{new}}.
2232 @item --enable-linker-build-id
2233 Tells GCC to pass @option{--build-id} option to the linker for all final
2234 links (links performed without the @option{-r} or @option{--relocatable}
2235 option), if the linker supports it. If you specify
2236 @option{--enable-linker-build-id}, but your linker does not
2237 support @option{--build-id} option, a warning is issued and the
2238 @option{--enable-linker-build-id} option is ignored. The default is off.
2240 @item --with-linker-hash-style=@var{choice}
2241 Tells GCC to pass @option{--hash-style=@var{choice}} option to the
2242 linker for all final links. @var{choice} can be one of
2243 @samp{sysv}, @samp{gnu}, and @samp{both} where @samp{sysv} is the default.
2245 @item --enable-gnu-unique-object
2246 @itemx --disable-gnu-unique-object
2247 Tells GCC to use the gnu_unique_object relocation for C++ template
2248 static data members and inline function local statics. Enabled by
2249 default for a toolchain with an assembler that accepts it and
2250 GLIBC 2.11 or above, otherwise disabled.
2252 @item --with-diagnostics-color=@var{choice}
2253 Tells GCC to use @var{choice} as the default for @option{-fdiagnostics-color=}
2254 option (if not used explicitly on the command line). @var{choice}
2255 can be one of @samp{never}, @samp{auto}, @samp{always}, and @samp{auto-if-env}
2256 where @samp{auto} is the default. @samp{auto-if-env} makes
2257 @option{-fdiagnostics-color=auto} the default if @env{GCC_COLORS}
2258 is present and non-empty in the environment of the compiler, and
2259 @option{-fdiagnostics-color=never} otherwise.
2261 @item --with-diagnostics-urls=@var{choice}
2262 Tells GCC to use @var{choice} as the default for @option{-fdiagnostics-urls=}
2263 option (if not used explicitly on the command line). @var{choice}
2264 can be one of @samp{never}, @samp{auto}, @samp{always}, and @samp{auto-if-env}
2265 where @samp{auto} is the default. @samp{auto-if-env} makes
2266 @option{-fdiagnostics-urls=auto} the default if @env{GCC_URLS}
2267 or @env{TERM_URLS} is present and non-empty in the environment of the
2268 compiler, and @option{-fdiagnostics-urls=never} otherwise.
2271 @itemx --disable-lto
2272 Enable support for link-time optimization (LTO). This is enabled by
2273 default, and may be disabled using @option{--disable-lto}.
2275 @item --enable-linker-plugin-configure-flags=FLAGS
2276 @itemx --enable-linker-plugin-flags=FLAGS
2277 By default, linker plugins (such as the LTO plugin) are built for the
2278 host system architecture. For the case that the linker has a
2279 different (but run-time compatible) architecture, these flags can be
2280 specified to build plugins that are compatible to the linker. For
2281 example, if you are building GCC for a 64-bit x86_64
2282 (@samp{x86_64-pc-linux-gnu}) host system, but have a 32-bit x86
2283 GNU/Linux (@samp{i686-pc-linux-gnu}) linker executable (which is
2284 executable on the former system), you can configure GCC as follows for
2285 getting compatible linker plugins:
2288 % @var{srcdir}/configure \
2289 --host=x86_64-pc-linux-gnu \
2290 --enable-linker-plugin-configure-flags=--host=i686-pc-linux-gnu \
2291 --enable-linker-plugin-flags='CC=gcc\ -m32\ -Wl,-rpath,[...]/i686-pc-linux-gnu/lib'
2294 @item --with-plugin-ld=@var{pathname}
2295 Enable an alternate linker to be used at link-time optimization (LTO)
2296 link time when @option{-fuse-linker-plugin} is enabled.
2297 This linker should have plugin support such as gold starting with
2298 version 2.20 or GNU ld starting with version 2.21.
2299 See @option{-fuse-linker-plugin} for details.
2301 @item --enable-canonical-system-headers
2302 @itemx --disable-canonical-system-headers
2303 Enable system header path canonicalization for @file{libcpp}. This can
2304 produce shorter header file paths in diagnostics and dependency output
2305 files, but these changed header paths may conflict with some compilation
2306 environments. Enabled by default, and may be disabled using
2307 @option{--disable-canonical-system-headers}.
2309 @item --with-glibc-version=@var{major}.@var{minor}
2310 Tell GCC that when the GNU C Library (glibc) is used on the target it
2311 will be version @var{major}.@var{minor} or later. Normally this can
2312 be detected from the C library's header files, but this option may be
2313 needed when bootstrapping a cross toolchain without the header files
2314 available for building the initial bootstrap compiler.
2316 If GCC is configured with some multilibs that use glibc and some that
2317 do not, this option applies only to the multilibs that use glibc.
2318 However, such configurations may not work well as not all the relevant
2319 configuration in GCC is on a per-multilib basis.
2321 @item --enable-as-accelerator-for=@var{target}
2322 Build as offload target compiler. Specify offload host triple by @var{target}.
2324 @item --enable-offload-targets=@var{target1}[=@var{path1}],@dots{},@var{targetN}[=@var{pathN}]
2325 Enable offloading to targets @var{target1}, @dots{}, @var{targetN}.
2326 Offload compilers are expected to be already installed. Default search
2327 path for them is @file{@var{exec-prefix}}, but it can be changed by
2328 specifying paths @var{path1}, @dots{}, @var{pathN}.
2331 % @var{srcdir}/configure \
2332 --enable-offload-targets=x86_64-intelmicemul-linux-gnu=/path/to/x86_64/compiler,nvptx-none
2335 @item --enable-offload-defaulted
2337 Tell GCC that configured but not installed offload compilers and libgomp
2338 plugins are silently ignored. Useful for distribution compilers where
2339 those are in separate optional packages and where the presence or absence
2340 of those optional packages should determine the actual supported offloading
2341 target set rather than the GCC configure-time selection.
2343 @item --with-hsa-runtime=@var{pathname}
2344 @itemx --with-hsa-runtime-include=@var{pathname}
2345 @itemx --with-hsa-runtime-lib=@var{pathname}
2347 If you configure GCC with offloading which uses an HSA run-time such as
2348 AMDGCN but do not have the HSA run-time library installed in a standard
2349 location then you can explicitly specify the directory where they are
2350 installed. The @option{--with-hsa-runtime=@/@var{hsainstalldir}} option
2352 @option{--with-hsa-runtime-lib=@/@var{hsainstalldir}/lib} and
2353 @option{--with-hsa-runtime-include=@/@var{hsainstalldir}/include}.
2356 @itemx --disable-cet
2357 Enable building target run-time libraries with control-flow
2358 instrumentation, see @option{-fcf-protection} option. When
2359 @code{--enable-cet} is specified target libraries are configured
2360 to add @option{-fcf-protection} and, if needed, other target
2361 specific options to a set of building options.
2363 @code{--enable-cet=auto} is default. CET is enabled on Linux/x86 if
2364 target binutils supports @code{Intel CET} instructions and disabled
2365 otherwise. In this case, the target libraries are configured to get
2366 additional @option{-fcf-protection} option.
2368 @item --with-riscv-attribute=@samp{yes}, @samp{no} or @samp{default}
2369 Generate RISC-V attribute by default, in order to record extra build
2370 information in object.
2372 The option is disabled by default. It is enabled on RISC-V/ELF (bare-metal)
2373 target if target binutils supported.
2375 @item --enable-s390-excess-float-precision
2376 @itemx --disable-s390-excess-float-precision
2377 On s390(x) targets, enable treatment of float expressions with double precision
2378 when in standards-compliant mode (e.g., when @code{--std=c99} or
2379 @code{-fexcess-precision=standard} are given).
2381 For a native build and cross compiles that have target headers, the option's
2382 default is derived from glibc's behavior. When glibc clamps float_t to double,
2383 GCC follows and enables the option. For other cross compiles, the default is
2387 @subheading Cross-Compiler-Specific Options
2388 The following options only apply to building cross compilers.
2391 @item --with-toolexeclibdir=@var{dir}
2392 Specify the installation directory for libraries built with a cross compiler.
2393 The default is @option{$@{gcc_tooldir@}/lib}.
2395 @item --with-sysroot
2396 @itemx --with-sysroot=@var{dir}
2397 Tells GCC to consider @var{dir} as the root of a tree that contains
2398 (a subset of) the root filesystem of the target operating system.
2399 Target system headers, libraries and run-time object files will be
2400 searched for in there. More specifically, this acts as if
2401 @option{--sysroot=@var{dir}} was added to the default options of the built
2402 compiler. The specified directory is not copied into the
2403 install tree, unlike the options @option{--with-headers} and
2404 @option{--with-libs} that this option obsoletes. The default value,
2405 in case @option{--with-sysroot} is not given an argument, is
2406 @option{$@{gcc_tooldir@}/sys-root}. If the specified directory is a
2407 subdirectory of @option{$@{exec_prefix@}}, then it will be found relative to
2408 the GCC binaries if the installation tree is moved.
2410 This option affects the system root for the compiler used to build
2411 target libraries (which runs on the build system) and the compiler newly
2412 installed with @code{make install}; it does not affect the compiler which is
2413 used to build GCC itself.
2415 If you specify the @option{--with-native-system-header-dir=@var{dirname}}
2416 option then the compiler will search that directory within @var{dirname} for
2417 native system headers rather than the default @file{/usr/include}.
2419 @item --with-build-sysroot
2420 @itemx --with-build-sysroot=@var{dir}
2421 Tells GCC to consider @var{dir} as the system root (see
2422 @option{--with-sysroot}) while building target libraries, instead of
2423 the directory specified with @option{--with-sysroot}. This option is
2424 only useful when you are already using @option{--with-sysroot}. You
2425 can use @option{--with-build-sysroot} when you are configuring with
2426 @option{--prefix} set to a directory that is different from the one in
2427 which you are installing GCC and your target libraries.
2429 This option affects the system root for the compiler used to build
2430 target libraries (which runs on the build system); it does not affect
2431 the compiler which is used to build GCC itself.
2433 If you specify the @option{--with-native-system-header-dir=@var{dirname}}
2434 option then the compiler will search that directory within @var{dirname} for
2435 native system headers rather than the default @file{/usr/include}.
2437 @item --with-headers
2438 @itemx --with-headers=@var{dir}
2439 Deprecated in favor of @option{--with-sysroot}.
2440 Specifies that target headers are available when building a cross compiler.
2441 The @var{dir} argument specifies a directory which has the target include
2442 files. These include files will be copied into the @file{gcc} install
2443 directory. @emph{This option with the @var{dir} argument is required} when
2444 building a cross compiler, if @file{@var{prefix}/@var{target}/sys-include}
2445 doesn't pre-exist. If @file{@var{prefix}/@var{target}/sys-include} does
2446 pre-exist, the @var{dir} argument may be omitted. @command{fixincludes}
2447 will be run on these files to make them compatible with GCC@.
2449 @item --without-headers
2450 Tells GCC not use any target headers from a libc when building a cross
2451 compiler. When crossing to GNU/Linux, you need the headers so GCC
2452 can build the exception handling for libgcc.
2455 @itemx --with-libs="@var{dir1} @var{dir2} @dots{} @var{dirN}"
2456 Deprecated in favor of @option{--with-sysroot}.
2457 Specifies a list of directories which contain the target runtime
2458 libraries. These libraries will be copied into the @file{gcc} install
2459 directory. If the directory list is omitted, this option has no
2463 Specifies that @samp{newlib} is
2464 being used as the target C library. This causes @code{__eprintf} to be
2465 omitted from @file{libgcc.a} on the assumption that it will be provided by
2471 @item --with-avrlibc
2472 Only supported for the AVR target. Specifies that @samp{AVR-Libc} is
2473 being used as the target C@tie{} library. This causes float support
2474 functions like @code{__addsf3} to be omitted from @file{libgcc.a} on
2475 the assumption that it will be provided by @file{libm.a}. For more
2476 technical details, cf. @uref{https://gcc.gnu.org/PR54461,,PR54461}.
2477 It is not supported for
2478 RTEMS configurations, which currently use newlib. The option is
2479 supported since version 4.7.2 and is the default in 4.8.0 and newer.
2481 @item --with-double=@{32|64|32,64|64,32@}
2482 @itemx --with-long-double=@{32|64|32,64|64,32|double@}
2483 Only supported for the AVR target since version@tie{}10.
2484 Specify the default layout available for the C/C++ @samp{double}
2485 and @samp{long double} type, respectively. The following rules apply:
2488 The first value after the @samp{=} specifies the default layout (in bits)
2489 of the type and also the default for the @option{-mdouble=} resp.
2490 @option{-mlong-double=} compiler option.
2492 If more than one value is specified, respective multilib variants are
2493 available, and @option{-mdouble=} resp. @option{-mlong-double=} acts
2494 as a multilib option.
2496 If @option{--with-long-double=double} is specified, @samp{double} and
2497 @samp{long double} will have the same layout.
2499 The defaults are @option{--with-long-double=64,32} and
2500 @option{--with-double=32,64}. The default @samp{double} layout imposed by
2501 the latter is compatible with older versions of the compiler that implement
2502 @samp{double} as a 32-bit type, which does not comply to the language standard.
2504 Not all combinations of @option{--with-double=} and
2505 @option{--with-long-double=} are valid. For example, the combination
2506 @option{--with-double=32,64} @option{--with-long-double=32} will be
2507 rejected because the first option specifies the availability of
2508 multilibs for @samp{double}, whereas the second option implies
2509 that @samp{long double} --- and hence also @samp{double} --- is always
2512 @item --with-double-comparison=@{tristate|bool|libf7@}
2513 Only supported for the AVR target since version@tie{}10.
2514 Specify what result format is returned by library functions that
2515 compare 64-bit floating point values (@code{DFmode}).
2516 The GCC default is @samp{tristate}. If the floating point
2517 implementation returns a boolean instead, set it to @samp{bool}.
2519 @item --with-libf7=@{libgcc|math|math-symbols|no@}
2520 Only supported for the AVR target since version@tie{}10.
2521 Specify to which degree code from LibF7 is included in libgcc.
2522 LibF7 is an ad-hoc, AVR-specific, 64-bit floating point emulation
2523 written in C and (inline) assembly. @samp{libgcc} adds support
2524 for functions that one would usually expect in libgcc like double addition,
2525 double comparisons and double conversions. @samp{math} also adds routines
2526 that one would expect in @file{libm.a}, but with @code{__} (two underscores)
2527 prepended to the symbol names as specified by @file{math.h}.
2528 @samp{math-symbols} also defines weak aliases for the functions
2529 declared in @file{math.h}. However, @code{--with-libf7} won't
2530 install no @file{math.h} header file whatsoever, this file must come
2531 from elsewhere. This option sets @option{--with-double-comparison}
2534 @item --with-nds32-lib=@var{library}
2535 Specifies that @var{library} setting is used for building @file{libgcc.a}.
2536 Currently, the valid @var{library} is @samp{newlib} or @samp{mculib}.
2537 This option is only supported for the NDS32 target.
2539 @item --with-build-time-tools=@var{dir}
2540 Specifies where to find the set of target tools (assembler, linker, etc.)
2541 that will be used while building GCC itself. This option can be useful
2542 if the directory layouts are different between the system you are building
2543 GCC on, and the system where you will deploy it.
2545 For example, on an @samp{ia64-hp-hpux} system, you may have the GNU
2546 assembler and linker in @file{/usr/bin}, and the native tools in a
2547 different path, and build a toolchain that expects to find the
2548 native tools in @file{/usr/bin}.
2550 When you use this option, you should ensure that @var{dir} includes
2551 @command{ar}, @command{as}, @command{ld}, @command{nm},
2552 @command{ranlib} and @command{strip} if necessary, and possibly
2553 @command{objdump}. Otherwise, GCC may use an inconsistent set of
2557 @subsubheading Overriding @command{configure} test results
2559 Sometimes, it might be necessary to override the result of some
2560 @command{configure} test, for example in order to ease porting to a new
2561 system or work around a bug in a test. The toplevel @command{configure}
2562 script provides three variables for this:
2566 @item build_configargs
2567 @cindex @code{build_configargs}
2568 The contents of this variable is passed to all build @command{configure}
2571 @item host_configargs
2572 @cindex @code{host_configargs}
2573 The contents of this variable is passed to all host @command{configure}
2576 @item target_configargs
2577 @cindex @code{target_configargs}
2578 The contents of this variable is passed to all target @command{configure}
2583 In order to avoid shell and @command{make} quoting issues for complex
2584 overrides, you can pass a setting for @env{CONFIG_SITE} and set
2585 variables in the site file.
2587 @subheading Objective-C-Specific Options
2589 The following options apply to the build of the Objective-C runtime library.
2592 @item --enable-objc-gc
2593 Specify that an additional variant of the GNU Objective-C runtime library
2594 is built, using an external build of the Boehm-Demers-Weiser garbage
2595 collector (@uref{https://www.hboehm.info/gc/}). This library needs to be
2596 available for each multilib variant, unless configured with
2597 @option{--enable-objc-gc=@samp{auto}} in which case the build of the
2598 additional runtime library is skipped when not available and the build
2601 @item --with-target-bdw-gc=@var{list}
2602 @itemx --with-target-bdw-gc-include=@var{list}
2603 @itemx --with-target-bdw-gc-lib=@var{list}
2604 Specify search directories for the garbage collector header files and
2605 libraries. @var{list} is a comma separated list of key value pairs of the
2606 form @samp{@var{multilibdir}=@var{path}}, where the default multilib key
2607 is named as @samp{.} (dot), or is omitted (e.g.@:
2608 @samp{--with-target-bdw-gc=/opt/bdw-gc,32=/opt-bdw-gc32}).
2610 The options @option{--with-target-bdw-gc-include} and
2611 @option{--with-target-bdw-gc-lib} must always be specified together
2612 for each multilib variant and they take precedence over
2613 @option{--with-target-bdw-gc}. If @option{--with-target-bdw-gc-include}
2614 is missing values for a multilib, then the value for the default
2615 multilib is used (e.g.@: @samp{--with-target-bdw-gc-include=/opt/bdw-gc/include}
2616 @samp{--with-target-bdw-gc-lib=/opt/bdw-gc/lib64,32=/opt-bdw-gc/lib32}).
2617 If none of these options are specified, the library is assumed in
2621 @subheading D-Specific Options
2623 The following options apply to the build of the D runtime library.
2626 @item --enable-libphobos-checking
2627 @itemx --disable-libphobos-checking
2628 @itemx --enable-libphobos-checking=@var{list}
2629 This option controls whether run-time checks and contracts are compiled into
2630 the D runtime library. When the option is not specified, the library is built
2631 with @samp{release} checking. When the option is specified without a
2632 @var{list}, the result is the same as @samp{--enable-libphobos-checking=yes}.
2633 Likewise, @samp{--disable-libphobos-checking} is equivalent to
2634 @samp{--enable-libphobos-checking=no}.
2636 The categories of checks available in @var{list} are @samp{yes} (compiles
2637 libphobos with @option{-fno-release}), @samp{no} (compiles libphobos with
2638 @option{-frelease}), @samp{all} (same as @samp{yes}), @samp{none} or
2639 @samp{release} (same as @samp{no}).
2641 Individual checks available in @var{list} are @samp{assert} (compiles libphobos
2642 with an extra option @option{-fassert}).
2644 @item --with-libphobos-druntime-only
2645 @itemx --with-libphobos-druntime-only=@var{choice}
2646 Specify whether to build only the core D runtime library (druntime), or both
2647 the core and standard library (phobos) into libphobos. This is useful for
2648 targets that have full support in druntime, but no or incomplete support
2649 in phobos. @var{choice} can be one of @samp{auto}, @samp{yes}, and @samp{no}
2650 where @samp{auto} is the default.
2652 When the option is not specified, the default choice @samp{auto} means that it
2653 is inferred whether the target has support for the phobos standard library.
2654 When the option is specified without a @var{choice}, the result is the same as
2655 @samp{--with-libphobos-druntime-only=yes}.
2657 @item --with-target-system-zlib
2658 Use installed @samp{zlib} rather than that included with GCC@. This needs
2659 to be available for each multilib variant, unless configured with
2660 @option{--with-target-system-zlib=@samp{auto}} in which case the GCC@ included
2661 @samp{zlib} is only used when the system installed library is not available.
2669 @uref{./index.html,,Return to the GCC Installation page}
2673 @c ***Building****************************************************************
2675 @comment node-name, next, previous, up
2676 @node Building, Testing, Configuration, Installing GCC
2682 @cindex Installing GCC: Building
2684 Now that GCC is configured, you are ready to build the compiler and
2687 Some commands executed when making the compiler may fail (return a
2688 nonzero status) and be ignored by @command{make}. These failures, which
2689 are often due to files that were not found, are expected, and can safely
2692 It is normal to have compiler warnings when compiling certain files.
2693 Unless you are a GCC developer, you can generally ignore these warnings
2694 unless they cause compilation to fail. Developers should attempt to fix
2695 any warnings encountered, however they can temporarily continue past
2696 warnings-as-errors by specifying the configure flag
2697 @option{--disable-werror}.
2699 On certain old systems, defining certain environment variables such as
2700 @env{CC} can interfere with the functioning of @command{make}.
2702 If you encounter seemingly strange errors when trying to build the
2703 compiler in a directory other than the source directory, it could be
2704 because you have previously configured the compiler in the source
2705 directory. Make sure you have done all the necessary preparations.
2707 If you build GCC on a BSD system using a directory stored in an old System
2708 V file system, problems may occur in running @command{fixincludes} if the
2709 System V file system doesn't support symbolic links. These problems
2710 result in a failure to fix the declaration of @code{size_t} in
2711 @file{sys/types.h}. If you find that @code{size_t} is a signed type and
2712 that type mismatches occur, this could be the cause.
2714 The solution is not to use such a directory for building GCC@.
2716 Similarly, when building from the source repository or snapshots, or if you modify
2717 @file{*.l} files, you need the Flex lexical analyzer generator
2718 installed. If you do not modify @file{*.l} files, releases contain
2719 the Flex-generated files and you do not need Flex installed to build
2720 them. There is still one Flex-based lexical analyzer (part of the
2721 build machinery, not of GCC itself) that is used even if you only
2722 build the C front end.
2724 When building from the source repository or snapshots, or if you modify Texinfo
2725 documentation, you need version 4.7 or later of Texinfo installed if you
2726 want Info documentation to be regenerated. Releases contain Info
2727 documentation pre-built for the unmodified documentation in the release.
2729 @section Building a native compiler
2731 For a native build, the default configuration is to perform
2732 a 3-stage bootstrap of the compiler when @samp{make} is invoked.
2733 This will build the entire GCC system and ensure that it compiles
2734 itself correctly. It can be disabled with the @option{--disable-bootstrap}
2735 parameter to @samp{configure}, but bootstrapping is suggested because
2736 the compiler will be tested more completely and could also have
2739 The bootstrapping process will complete the following steps:
2743 Build tools necessary to build the compiler.
2746 Perform a 3-stage bootstrap of the compiler. This includes building
2747 three times the target tools for use by the compiler such as binutils
2748 (bfd, binutils, gas, gprof, ld, and opcodes) if they have been
2749 individually linked or moved into the top level GCC source tree before
2753 Perform a comparison test of the stage2 and stage3 compilers.
2756 Build runtime libraries using the stage3 compiler from the previous step.
2760 If you are short on disk space you might consider @samp{make
2761 bootstrap-lean} instead. The sequence of compilation is the
2762 same described above, but object files from the stage1 and
2763 stage2 of the 3-stage bootstrap of the compiler are deleted as
2764 soon as they are no longer needed.
2766 If you wish to use non-default GCC flags when compiling the stage2
2767 and stage3 compilers, set @code{BOOT_CFLAGS} on the command line when
2768 doing @samp{make}. For example, if you want to save additional space
2769 during the bootstrap and in the final installation as well, you can
2770 build the compiler binaries without debugging information as in the
2771 following example. This will save roughly 40% of disk space both for
2772 the bootstrap and the final installation. (Libraries will still contain
2773 debugging information.)
2776 make BOOT_CFLAGS='-O' bootstrap
2779 You can place non-default optimization flags into @code{BOOT_CFLAGS}; they
2780 are less well tested here than the default of @samp{-g -O2}, but should
2781 still work. In a few cases, you may find that you need to specify special
2782 flags such as @option{-msoft-float} here to complete the bootstrap; or,
2783 if the native compiler miscompiles the stage1 compiler, you may need
2784 to work around this, by choosing @code{BOOT_CFLAGS} to avoid the parts
2785 of the stage1 compiler that were miscompiled, or by using @samp{make
2786 bootstrap4} to increase the number of stages of bootstrap.
2788 @code{BOOT_CFLAGS} does not apply to bootstrapped target libraries.
2789 Since these are always compiled with the compiler currently being
2790 bootstrapped, you can use @code{CFLAGS_FOR_TARGET} to modify their
2791 compilation flags, as for non-bootstrapped target libraries.
2792 Again, if the native compiler miscompiles the stage1 compiler, you may
2793 need to work around this by avoiding non-working parts of the stage1
2794 compiler. Use @code{STAGE1_TFLAGS} to this end.
2796 If you used the flag @option{--enable-languages=@dots{}} to restrict
2797 the compilers to be built, only those you've actually enabled will be
2798 built. This will of course only build those runtime libraries, for
2799 which the particular compiler has been built. Please note,
2800 that re-defining @env{LANGUAGES} when calling @samp{make}
2801 @strong{does not} work anymore!
2803 If the comparison of stage2 and stage3 fails, this normally indicates
2804 that the stage2 compiler has compiled GCC incorrectly, and is therefore
2805 a potentially serious bug which you should investigate and report. (On
2806 a few systems, meaningful comparison of object files is impossible; they
2807 always appear ``different''. If you encounter this problem, you will
2808 need to disable comparison in the @file{Makefile}.)
2810 If you do not want to bootstrap your compiler, you can configure with
2811 @option{--disable-bootstrap}. In particular cases, you may want to
2812 bootstrap your compiler even if the target system is not the same as
2813 the one you are building on: for example, you could build a
2814 @code{powerpc-unknown-linux-gnu} toolchain on a
2815 @code{powerpc64-unknown-linux-gnu} host. In this case, pass
2816 @option{--enable-bootstrap} to the configure script.
2818 @code{BUILD_CONFIG} can be used to bring in additional customization
2819 to the build. It can be set to a whitespace-separated list of names.
2820 For each such @code{NAME}, top-level @file{config/@code{NAME}.mk} will
2821 be included by the top-level @file{Makefile}, bringing in any settings
2822 it contains. The default @code{BUILD_CONFIG} can be set using the
2823 configure option @option{--with-build-config=@code{NAME}...}. Some
2824 examples of supported build configurations are:
2827 @item @samp{bootstrap-O1}
2828 Removes any @option{-O}-started option from @code{BOOT_CFLAGS}, and adds
2829 @option{-O1} to it. @samp{BUILD_CONFIG=bootstrap-O1} is equivalent to
2830 @samp{BOOT_CFLAGS='-g -O1'}.
2832 @item @samp{bootstrap-O3}
2833 @itemx @samp{bootstrap-Og}
2834 Analogous to @code{bootstrap-O1}.
2836 @item @samp{bootstrap-lto}
2837 Enables Link-Time Optimization for host tools during bootstrapping.
2838 @samp{BUILD_CONFIG=bootstrap-lto} is equivalent to adding
2839 @option{-flto} to @samp{BOOT_CFLAGS}. This option assumes that the host
2840 supports the linker plugin (e.g.@: GNU ld version 2.21 or later or GNU gold
2841 version 2.21 or later).
2843 @item @samp{bootstrap-lto-noplugin}
2844 This option is similar to @code{bootstrap-lto}, but is intended for
2845 hosts that do not support the linker plugin. Without the linker plugin
2846 static libraries are not compiled with link-time optimizations. Since
2847 the GCC middle end and back end are in @file{libbackend.a} this means
2848 that only the front end is actually LTO optimized.
2850 @item @samp{bootstrap-lto-lean}
2851 This option is similar to @code{bootstrap-lto}, but is intended for
2852 faster build by only using LTO in the final bootstrap stage.
2853 With @samp{make profiledbootstrap} the LTO frontend
2854 is trained only on generator files.
2856 @item @samp{bootstrap-debug}
2857 Verifies that the compiler generates the same executable code, whether
2858 or not it is asked to emit debug information. To this end, this
2859 option builds stage2 host programs without debug information, and uses
2860 @file{contrib/compare-debug} to compare them with the stripped stage3
2861 object files. If @code{BOOT_CFLAGS} is overridden so as to not enable
2862 debug information, stage2 will have it, and stage3 won't. This option
2863 is enabled by default when GCC bootstrapping is enabled, if
2864 @code{strip} can turn object files compiled with and without debug
2865 info into identical object files. In addition to better test
2866 coverage, this option makes default bootstraps faster and leaner.
2868 @item @samp{bootstrap-debug-big}
2869 Rather than comparing stripped object files, as in
2870 @code{bootstrap-debug}, this option saves internal compiler dumps
2871 during stage2 and stage3 and compares them as well, which helps catch
2872 additional potential problems, but at a great cost in terms of disk
2873 space. It can be specified in addition to @samp{bootstrap-debug}.
2875 @item @samp{bootstrap-debug-lean}
2876 This option saves disk space compared with @code{bootstrap-debug-big},
2877 but at the expense of some recompilation. Instead of saving the dumps
2878 of stage2 and stage3 until the final compare, it uses
2879 @option{-fcompare-debug} to generate, compare and remove the dumps
2880 during stage3, repeating the compilation that already took place in
2881 stage2, whose dumps were not saved.
2883 @item @samp{bootstrap-debug-lib}
2884 This option tests executable code invariance over debug information
2885 generation on target libraries, just like @code{bootstrap-debug-lean}
2886 tests it on host programs. It builds stage3 libraries with
2887 @option{-fcompare-debug}, and it can be used along with any of the
2888 @code{bootstrap-debug} options above.
2890 There aren't @code{-lean} or @code{-big} counterparts to this option
2891 because most libraries are only build in stage3, so bootstrap compares
2892 would not get significant coverage. Moreover, the few libraries built
2893 in stage2 are used in stage3 host programs, so we wouldn't want to
2894 compile stage2 libraries with different options for comparison purposes.
2896 @item @samp{bootstrap-debug-ckovw}
2897 Arranges for error messages to be issued if the compiler built on any
2898 stage is run without the option @option{-fcompare-debug}. This is
2899 useful to verify the full @option{-fcompare-debug} testing coverage. It
2900 must be used along with @code{bootstrap-debug-lean} and
2901 @code{bootstrap-debug-lib}.
2903 @item @samp{bootstrap-cet}
2904 This option enables Intel CET for host tools during bootstrapping.
2905 @samp{BUILD_CONFIG=bootstrap-cet} is equivalent to adding
2906 @option{-fcf-protection} to @samp{BOOT_CFLAGS}. This option
2907 assumes that the host supports Intel CET (e.g.@: GNU assembler version
2910 @item @samp{bootstrap-time}
2911 Arranges for the run time of each program started by the GCC driver,
2912 built in any stage, to be logged to @file{time.log}, in the top level of
2915 @item @samp{bootstrap-asan}
2916 Compiles GCC itself using Address Sanitization in order to catch invalid memory
2917 accesses within the GCC code.
2919 @item @samp{bootstrap-hwasan}
2920 Compiles GCC itself using HWAddress Sanitization in order to catch invalid
2921 memory accesses within the GCC code. This option is only available on AArch64
2922 systems that are running Linux kernel version 5.4 or later.
2926 @section Building a cross compiler
2928 When building a cross compiler, it is not generally possible to do a
2929 3-stage bootstrap of the compiler. This makes for an interesting problem
2930 as parts of GCC can only be built with GCC@.
2932 To build a cross compiler, we recommend first building and installing a
2933 native compiler. You can then use the native GCC compiler to build the
2934 cross compiler. The installed native compiler needs to be GCC version
2937 Assuming you have already installed a native copy of GCC and configured
2938 your cross compiler, issue the command @command{make}, which performs the
2943 Build host tools necessary to build the compiler.
2946 Build target tools for use by the compiler such as binutils (bfd,
2947 binutils, gas, gprof, ld, and opcodes)
2948 if they have been individually linked or moved into the top level GCC source
2949 tree before configuring.
2952 Build the compiler (single stage only).
2955 Build runtime libraries using the compiler from the previous step.
2958 Note that if an error occurs in any step the make process will exit.
2960 If you are not building GNU binutils in the same source tree as GCC,
2961 you will need a cross-assembler and cross-linker installed before
2962 configuring GCC@. Put them in the directory
2963 @file{@var{prefix}/@var{target}/bin}. Here is a table of the tools
2964 you should put in this directory:
2968 This should be the cross-assembler.
2971 This should be the cross-linker.
2974 This should be the cross-archiver: a program which can manipulate
2975 archive files (linker libraries) in the target machine's format.
2978 This should be a program to construct a symbol table in an archive file.
2981 The installation of GCC will find these programs in that directory,
2982 and copy or link them to the proper place to for the cross-compiler to
2983 find them when run later.
2985 The easiest way to provide these files is to build the Binutils package.
2986 Configure it with the same @option{--host} and @option{--target}
2987 options that you use for configuring GCC, then build and install
2988 them. They install their executables automatically into the proper
2989 directory. Alas, they do not support all the targets that GCC
2992 If you are not building a C library in the same source tree as GCC,
2993 you should also provide the target libraries and headers before
2994 configuring GCC, specifying the directories with
2995 @option{--with-sysroot} or @option{--with-headers} and
2996 @option{--with-libs}. Many targets also require ``start files'' such
2997 as @file{crt0.o} and
2998 @file{crtn.o} which are linked into each executable. There may be several
2999 alternatives for @file{crt0.o}, for use with profiling or other
3000 compilation options. Check your target's definition of
3001 @code{STARTFILE_SPEC} to find out what start files it uses.
3003 @section Building in parallel
3005 GNU Make 3.80 and above, which is necessary to build GCC, support
3006 building in parallel. To activate this, you can use @samp{make -j 2}
3007 instead of @samp{make}. You can also specify a bigger number, and
3008 in most cases using a value greater than the number of processors in
3009 your machine will result in fewer and shorter I/O latency hits, thus
3010 improving overall throughput; this is especially true for slow drives
3011 and network filesystems.
3013 @section Building the Ada compiler
3016 @ref{GNAT-prerequisite}.
3019 @uref{prerequisites.html#GNAT-prerequisite,,GNAT prerequisites}.
3022 @section Building the D compiler
3025 @ref{GDC-prerequisite}.
3028 @uref{prerequisites.html#GDC-prerequisite,,GDC prerequisites}.
3031 @section Building with profile feedback
3033 It is possible to use profile feedback to optimize the compiler itself. This
3034 should result in a faster compiler binary. Experiments done on x86 using gcc
3035 3.3 showed approximately 7 percent speedup on compiling C programs. To
3036 bootstrap the compiler with profile feedback, use @code{make profiledbootstrap}.
3038 When @samp{make profiledbootstrap} is run, it will first build a @code{stage1}
3039 compiler. This compiler is used to build a @code{stageprofile} compiler
3040 instrumented to collect execution counts of instruction and branch
3041 probabilities. Training run is done by building @code{stagetrain}
3042 compiler. Finally a @code{stagefeedback} compiler is built
3043 using the information collected.
3045 Unlike standard bootstrap, several additional restrictions apply. The
3046 compiler used to build @code{stage1} needs to support a 64-bit integral type.
3047 It is recommended to only use GCC for this.
3049 On Linux/x86_64 hosts with some restrictions (no virtualization) it is
3050 also possible to do autofdo build with @samp{make
3051 autoprofiledback}. This uses Linux perf to sample branches in the
3052 binary and then rebuild it with feedback derived from the profile.
3053 Linux perf and the @code{autofdo} toolkit needs to be installed for
3056 Only the profile from the current build is used, so when an error
3057 occurs it is recommended to clean before restarting. Otherwise
3058 the code quality may be much worse.
3065 @uref{./index.html,,Return to the GCC Installation page}
3069 @c ***Testing*****************************************************************
3071 @comment node-name, next, previous, up
3072 @node Testing, Final install, Building, Installing GCC
3076 @chapter Installing GCC: Testing
3079 @cindex Installing GCC: Testing
3082 Before you install GCC, we encourage you to run the testsuites and to
3083 compare your results with results from a similar configuration that have
3084 been submitted to the
3085 @uref{https://gcc.gnu.org/ml/gcc-testresults/,,gcc-testresults mailing list}.
3086 Some of these archived results are linked from the build status lists
3087 at @uref{https://gcc.gnu.org/buildstat.html}, although not everyone who
3088 reports a successful build runs the testsuites and submits the results.
3089 This step is optional and may require you to download additional software,
3090 but it can give you confidence in your new GCC installation or point out
3091 problems before you install and start using your new GCC@.
3093 First, you must have @uref{download.html,,downloaded the testsuites}.
3094 These are part of the full distribution, but if you downloaded the
3095 ``core'' compiler plus any front ends, you must download the testsuites
3098 Second, you must have the testing tools installed. This includes
3099 @uref{https://www.gnu.org/software/dejagnu/,,DejaGnu}, Tcl, and Expect;
3100 the DejaGnu site has links to these.
3101 Some optional tests also require Python3 and pytest module.
3103 If the directories where @command{runtest} and @command{expect} were
3104 installed are not in the @env{PATH}, you may need to set the following
3105 environment variables appropriately, as in the following example (which
3106 assumes that DejaGnu has been installed under @file{/usr/local}):
3109 TCL_LIBRARY = /usr/local/share/tcl8.0
3110 DEJAGNULIBS = /usr/local/share/dejagnu
3113 (On systems such as Cygwin, these paths are required to be actual
3114 paths, not mounts or links; presumably this is due to some lack of
3115 portability in the DejaGnu code.)
3118 Finally, you can run the testsuite (which may take a long time):
3120 cd @var{objdir}; make -k check
3123 This will test various components of GCC, such as compiler
3124 front ends and runtime libraries. While running the testsuite, DejaGnu
3125 might emit some harmless messages resembling
3126 @samp{WARNING: Couldn't find the global config file.} or
3127 @samp{WARNING: Couldn't find tool init file} that can be ignored.
3129 If you are testing a cross-compiler, you may want to run the testsuite
3130 on a simulator as described at @uref{https://gcc.gnu.org/simtest-howto.html}.
3132 @section How can you run the testsuite on selected tests?
3134 In order to run sets of tests selectively, there are targets
3135 @samp{make check-gcc} and language specific @samp{make check-c},
3136 @samp{make check-c++}, @samp{make check-d} @samp{make check-fortran},
3137 @samp{make check-ada}, @samp{make check-objc}, @samp{make check-obj-c++},
3138 @samp{make check-lto}
3139 in the @file{gcc} subdirectory of the object directory. You can also
3140 just run @samp{make check} in a subdirectory of the object directory.
3143 A more selective way to just run all @command{gcc} execute tests in the
3147 make check-gcc RUNTESTFLAGS="execute.exp @var{other-options}"
3150 Likewise, in order to run only the @command{g++} ``old-deja'' tests in
3151 the testsuite with filenames matching @samp{9805*}, you would use
3154 make check-g++ RUNTESTFLAGS="old-deja.exp=9805* @var{other-options}"
3157 The file-matching expression following @var{filename}@command{.exp=} is treated
3158 as a series of whitespace-delimited glob expressions so that multiple patterns
3159 may be passed, although any whitespace must either be escaped or surrounded by
3160 single quotes if multiple expressions are desired. For example,
3163 make check-g++ RUNTESTFLAGS="old-deja.exp=9805*\ virtual2.c @var{other-options}"
3164 make check-g++ RUNTESTFLAGS="'old-deja.exp=9805* virtual2.c' @var{other-options}"
3167 The @file{*.exp} files are located in the testsuite directories of the GCC
3168 source, the most important ones being @file{compile.exp},
3169 @file{execute.exp}, @file{dg.exp} and @file{old-deja.exp}.
3170 To get a list of the possible @file{*.exp} files, pipe the
3171 output of @samp{make check} into a file and look at the
3172 @samp{Running @dots{} .exp} lines.
3174 @section Passing options and running multiple testsuites
3176 You can pass multiple options to the testsuite using the
3177 @samp{--target_board} option of DejaGNU, either passed as part of
3178 @samp{RUNTESTFLAGS}, or directly to @command{runtest} if you prefer to
3179 work outside the makefiles. For example,
3182 make check-g++ RUNTESTFLAGS="--target_board=unix/-O3/-fmerge-constants"
3185 will run the standard @command{g++} testsuites (``unix'' is the target name
3186 for a standard native testsuite situation), passing
3187 @samp{-O3 -fmerge-constants} to the compiler on every test, i.e.,
3188 slashes separate options.
3190 You can run the testsuites multiple times using combinations of options
3191 with a syntax similar to the brace expansion of popular shells:
3194 @dots{}"--target_board=arm-sim\@{-mhard-float,-msoft-float\@}\@{-O1,-O2,-O3,\@}"
3197 (Note the empty option caused by the trailing comma in the final group.)
3198 The following will run each testsuite eight times using the @samp{arm-sim}
3199 target, as if you had specified all possible combinations yourself:
3202 --target_board='arm-sim/-mhard-float/-O1 \
3203 arm-sim/-mhard-float/-O2 \
3204 arm-sim/-mhard-float/-O3 \
3205 arm-sim/-mhard-float \
3206 arm-sim/-msoft-float/-O1 \
3207 arm-sim/-msoft-float/-O2 \
3208 arm-sim/-msoft-float/-O3 \
3209 arm-sim/-msoft-float'
3212 They can be combined as many times as you wish, in arbitrary ways. This
3216 @dots{}"--target_board=unix/-Wextra\@{-O3,-fno-strength\@}\@{-fomit-frame,\@}"
3219 will generate four combinations, all involving @samp{-Wextra}.
3221 The disadvantage to this method is that the testsuites are run in serial,
3222 which is a waste on multiprocessor systems. For users with GNU Make and
3223 a shell which performs brace expansion, you can run the testsuites in
3224 parallel by having the shell perform the combinations and @command{make}
3225 do the parallel runs. Instead of using @samp{--target_board}, use a
3226 special makefile target:
3229 make -j@var{N} check-@var{testsuite}//@var{test-target}/@var{option1}/@var{option2}/@dots{}
3235 make -j3 check-gcc//sh-hms-sim/@{-m1,-m2,-m3,-m3e,-m4@}/@{,-nofpu@}
3238 will run three concurrent ``make-gcc'' testsuites, eventually testing all
3239 ten combinations as described above. Note that this is currently only
3240 supported in the @file{gcc} subdirectory. (To see how this works, try
3241 typing @command{echo} before the example given here.)
3244 @section How to interpret test results
3246 The result of running the testsuite are various @file{*.sum} and @file{*.log}
3247 files in the testsuite subdirectories. The @file{*.log} files contain a
3248 detailed log of the compiler invocations and the corresponding
3249 results, the @file{*.sum} files summarize the results. These summaries
3250 contain status codes for all tests:
3254 PASS: the test passed as expected
3256 XPASS: the test unexpectedly passed
3258 FAIL: the test unexpectedly failed
3260 XFAIL: the test failed as expected
3262 UNSUPPORTED: the test is not supported on this platform
3264 ERROR: the testsuite detected an error
3266 WARNING: the testsuite detected a possible problem
3269 It is normal for some tests to report unexpected failures. At the
3270 current time the testing harness does not allow fine grained control
3271 over whether or not a test is expected to fail. This problem should
3272 be fixed in future releases.
3275 @section Submitting test results
3277 If you want to report the results to the GCC project, use the
3278 @file{contrib/test_summary} shell script. Start it in the @var{objdir} with
3281 @var{srcdir}/contrib/test_summary -p your_commentary.txt \
3282 -m gcc-testresults@@gcc.gnu.org |sh
3285 This script uses the @command{Mail} program to send the results, so
3286 make sure it is in your @env{PATH}. The file @file{your_commentary.txt} is
3287 prepended to the testsuite summary and should contain any special
3288 remarks you have on your results or your build environment. Please
3289 do not edit the testsuite result block or the subject line, as these
3290 messages may be automatically processed.
3297 @uref{./index.html,,Return to the GCC Installation page}
3301 @c ***Final install***********************************************************
3303 @comment node-name, next, previous, up
3304 @node Final install, , Testing, Installing GCC
3306 @ifset finalinstallhtml
3308 @chapter Installing GCC: Final installation
3311 Now that GCC has been built (and optionally tested), you can install it with
3313 cd @var{objdir} && make install
3316 We strongly recommend to install into a target directory where there is
3317 no previous version of GCC present. Also, the GNAT runtime should not
3318 be stripped, as this would break certain features of the debugger that
3319 depend on this debugging information (catching Ada exceptions for
3322 That step completes the installation of GCC; user level binaries can
3323 be found in @file{@var{prefix}/bin} where @var{prefix} is the value
3324 you specified with the @option{--prefix} to configure (or
3325 @file{/usr/local} by default). (If you specified @option{--bindir},
3326 that directory will be used instead; otherwise, if you specified
3327 @option{--exec-prefix}, @file{@var{exec-prefix}/bin} will be used.)
3328 Headers for the C++ library are installed in
3329 @file{@var{prefix}/include}; libraries in @file{@var{libdir}}
3330 (normally @file{@var{prefix}/lib}); internal parts of the compiler in
3331 @file{@var{libdir}/gcc} and @file{@var{libexecdir}/gcc}; documentation
3332 in info format in @file{@var{infodir}} (normally
3333 @file{@var{prefix}/info}).
3335 When installing cross-compilers, GCC's executables
3336 are not only installed into @file{@var{bindir}}, that
3337 is, @file{@var{exec-prefix}/bin}, but additionally into
3338 @file{@var{exec-prefix}/@var{target-alias}/bin}, if that directory
3339 exists. Typically, such @dfn{tooldirs} hold target-specific
3340 binutils, including assembler and linker.
3342 Installation into a temporary staging area or into a @command{chroot}
3343 jail can be achieved with the command
3346 make DESTDIR=@var{path-to-rootdir} install
3350 where @var{path-to-rootdir} is the absolute path of
3351 a directory relative to which all installation paths will be
3352 interpreted. Note that the directory specified by @code{DESTDIR}
3353 need not exist yet; it will be created if necessary.
3355 There is a subtle point with tooldirs and @code{DESTDIR}:
3356 If you relocate a cross-compiler installation with
3357 e.g.@: @samp{DESTDIR=@var{rootdir}}, then the directory
3358 @file{@var{rootdir}/@var{exec-prefix}/@var{target-alias}/bin} will
3359 be filled with duplicated GCC executables only if it already exists,
3360 it will not be created otherwise. This is regarded as a feature,
3361 not as a bug, because it gives slightly more control to the packagers
3362 using the @code{DESTDIR} feature.
3364 You can install stripped programs and libraries with
3370 If you are bootstrapping a released version of GCC then please
3371 quickly review the build status page for your release, available from
3372 @uref{https://gcc.gnu.org/buildstat.html}.
3373 If your system is not listed for the version of GCC that you built,
3375 @email{gcc@@gcc.gnu.org} indicating
3376 that you successfully built and installed GCC@.
3377 Include the following information:
3381 Output from running @file{@var{srcdir}/config.guess}. Do not send
3382 that file itself, just the one-line output from running it.
3385 The output of @samp{gcc -v} for your newly installed @command{gcc}.
3386 This tells us which version of GCC you built and the options you passed to
3390 Whether you enabled all languages or a subset of them. If you used a
3391 full distribution then this information is part of the configure
3392 options in the output of @samp{gcc -v}, but if you downloaded the
3393 ``core'' compiler plus additional front ends then it isn't apparent
3394 which ones you built unless you tell us about it.
3397 If the build was for GNU/Linux, also include:
3400 The distribution name and version (e.g., Red Hat 7.1 or Debian 2.2.3);
3401 this information should be available from @file{/etc/issue}.
3404 The version of the Linux kernel, available from @samp{uname --version}
3408 The version of glibc you used; for RPM-based systems like Red Hat,
3409 Mandrake, and SuSE type @samp{rpm -q glibc} to get the glibc version,
3410 and on systems like Debian and Progeny use @samp{dpkg -l libc6}.
3412 For other systems, you can include similar information if you think it is
3416 Any other information that you think would be useful to people building
3417 GCC on the same configuration. The new entry in the build status list
3418 will include a link to the archived copy of your message.
3421 We'd also like to know if the
3423 @ref{Specific, host/target specific installation notes}
3426 @uref{specific.html,,host/target specific installation notes}
3428 didn't include your host/target information or if that information is
3429 incomplete or out of date. Send a note to
3430 @email{gcc@@gcc.gnu.org} detailing how the information should be changed.
3432 If you find a bug, please report it following the
3433 @uref{../bugs/,,bug reporting guidelines}.
3435 If you want to print the GCC manuals, do @samp{cd @var{objdir}; make
3436 dvi}. You will need to have @command{texi2dvi} (version at least 4.7)
3437 and @TeX{} installed. This creates a number of @file{.dvi} files in
3438 subdirectories of @file{@var{objdir}}; these may be converted for
3439 printing with programs such as @command{dvips}. Alternately, by using
3440 @samp{make pdf} in place of @samp{make dvi}, you can create documentation
3441 in the form of @file{.pdf} files; this requires @command{texi2pdf}, which
3442 is included with Texinfo version 4.8 and later. You can also
3443 @uref{https://shop.fsf.org/,,buy printed manuals from the
3444 Free Software Foundation}, though such manuals may not be for the most
3445 recent version of GCC@.
3447 If you would like to generate online HTML documentation, do @samp{cd
3448 @var{objdir}; make html} and HTML will be generated for the gcc manuals in
3449 @file{@var{objdir}/gcc/HTML}.
3456 @uref{./index.html,,Return to the GCC Installation page}
3460 @c ***Binaries****************************************************************
3462 @comment node-name, next, previous, up
3463 @node Binaries, Specific, Installing GCC, Top
3467 @chapter Installing GCC: Binaries
3470 @cindex Installing GCC: Binaries
3472 We are often asked about pre-compiled versions of GCC@. While we cannot
3473 provide these for all platforms, below you'll find links to binaries for
3474 various platforms where creating them by yourself is not easy due to various
3477 Please note that we did not create these binaries, nor do we
3478 support them. If you have any problems installing them, please
3479 contact their makers.
3486 @uref{http://www.bullfreeware.com,,Bull's Open Source Software Archive for
3487 for AIX 6 and AIX 7};
3490 @uref{http://www.perzl.org/aix/,,AIX Open Source Packages (AIX5L AIX 6.1
3495 DOS---@uref{http://www.delorie.com/djgpp/,,DJGPP}.
3501 @uref{http://hpux.connect.org.uk/,,HP-UX Porting Center};
3505 Solaris 2 (SPARC, Intel):
3508 @uref{https://www.opencsw.org/,,OpenCSW}
3515 The @uref{https://brew.sh,,Homebrew} package manager;
3517 @uref{https://www.macports.org,,MacPorts}.
3524 The @uref{https://sourceware.org/cygwin/,,Cygwin} project;
3526 The @uref{https://osdn.net/projects/mingw/,,MinGW} and
3527 @uref{https://www.mingw-w64.org/,,mingw-w64} projects.
3531 @uref{http://www.openpkg.org/,,OpenPKG} offers binaries for quite a
3532 number of platforms.
3535 The @uref{https://gcc.gnu.org/wiki/GFortranBinaries,,GFortran Wiki} has
3536 links to GNU Fortran binaries for several platforms.
3544 @uref{./index.html,,Return to the GCC Installation page}
3548 @c ***Specific****************************************************************
3550 @comment node-name, next, previous, up
3551 @node Specific, GNU Free Documentation License, Binaries, Top
3555 @chapter Host/target specific installation notes for GCC
3558 @cindex Specific installation notes
3559 @cindex Target specific installation
3560 @cindex Host specific installation
3561 @cindex Target specific installation notes
3563 Please read this document carefully @emph{before} installing the
3564 GNU Compiler Collection on your machine.
3566 Note that this list of install notes is @emph{not} a list of supported
3567 hosts or targets. Not all supported hosts and targets are listed
3568 here, only the ones that require host-specific or target-specific
3569 information have to.
3574 @uref{#aarch64-x-x,,aarch64*-*-*}
3576 @uref{#alpha-x-x,,alpha*-*-*}
3578 @uref{#amd64-x-solaris2,,amd64-*-solaris2*}
3580 @uref{#arm-x-eabi,,arm-*-eabi}
3584 @uref{#bfin,,Blackfin}
3588 @uref{#x-x-freebsd,,*-*-freebsd*}
3590 @uref{#h8300-hms,,h8300-hms}
3592 @uref{#hppa-hp-hpux,,hppa*-hp-hpux*}
3594 @uref{#hppa-hp-hpux10,,hppa*-hp-hpux10}
3596 @uref{#hppa-hp-hpux11,,hppa*-hp-hpux11}
3598 @uref{#x-x-linux-gnu,,*-*-linux-gnu}
3600 @uref{#ix86-x-linux,,i?86-*-linux*}
3602 @uref{#ix86-x-solaris2,,i?86-*-solaris2*}
3604 @uref{#ia64-x-linux,,ia64-*-linux}
3606 @uref{#ia64-x-hpux,,ia64-*-hpux*}
3608 @uref{#x-ibm-aix,,*-ibm-aix*}
3610 @uref{#iq2000-x-elf,,iq2000-*-elf}
3612 @uref{#lm32-x-elf,,lm32-*-elf}
3614 @uref{#lm32-x-uclinux,,lm32-*-uclinux}
3616 @uref{#m32c-x-elf,,m32c-*-elf}
3618 @uref{#m32r-x-elf,,m32r-*-elf}
3620 @uref{#m68k-x-x,,m68k-*-*}
3622 @uref{#m68k-uclinux,,m68k-uclinux}
3624 @uref{#microblaze-x-elf,,microblaze-*-elf}
3626 @uref{#mips-x-x,,mips-*-*}
3628 @uref{#nds32le-x-elf,,nds32le-*-elf}
3630 @uref{#nds32be-x-elf,,nds32be-*-elf}
3632 @uref{#nvptx-x-none,,nvptx-*-none}
3634 @uref{#or1k-x-elf,,or1k-*-elf}
3636 @uref{#or1k-x-linux,,or1k-*-linux}
3638 @uref{#powerpc-x-x,,powerpc*-*-*}
3640 @uref{#powerpc-x-darwin,,powerpc-*-darwin*}
3642 @uref{#powerpc-x-elf,,powerpc-*-elf}
3644 @uref{#powerpc-x-linux-gnu,,powerpc*-*-linux-gnu*}
3646 @uref{#powerpc-x-netbsd,,powerpc-*-netbsd*}
3648 @uref{#powerpc-x-eabisim,,powerpc-*-eabisim}
3650 @uref{#powerpc-x-eabi,,powerpc-*-eabi}
3652 @uref{#powerpcle-x-elf,,powerpcle-*-elf}
3654 @uref{#powerpcle-x-eabisim,,powerpcle-*-eabisim}
3656 @uref{#powerpcle-x-eabi,,powerpcle-*-eabi}
3658 @uref{#riscv32-x-elf,,riscv32-*-elf}
3660 @uref{#riscv32-x-linux,,riscv32-*-linux}
3662 @uref{#riscv64-x-elf,,riscv64-*-elf}
3664 @uref{#riscv64-x-linux,,riscv64-*-linux}
3666 @uref{#s390-x-linux,,s390-*-linux*}
3668 @uref{#s390x-x-linux,,s390x-*-linux*}
3670 @uref{#s390x-ibm-tpf,,s390x-ibm-tpf*}
3672 @uref{#x-x-solaris2,,*-*-solaris2*}
3674 @uref{#sparc-x-x,,sparc*-*-*}
3676 @uref{#sparc-sun-solaris2,,sparc-sun-solaris2*}
3678 @uref{#sparc-x-linux,,sparc-*-linux*}
3680 @uref{#sparc64-x-solaris2,,sparc64-*-solaris2*}
3682 @uref{#sparcv9-x-solaris2,,sparcv9-*-solaris2*}
3684 @uref{#c6x-x-x,,c6x-*-*}
3686 @uref{#tilegx-x-linux,,tilegx-*-linux*}
3688 @uref{#tilegxbe-x-linux,,tilegxbe-*-linux*}
3690 @uref{#tilepro-x-linux,,tilepro-*-linux*}
3692 @uref{#visium-x-elf, visium-*-elf}
3694 @uref{#x-x-vxworks,,*-*-vxworks*}
3696 @uref{#x86-64-x-x,,x86_64-*-*, amd64-*-*}
3698 @uref{#x86-64-x-solaris2,,x86_64-*-solaris2*}
3700 @uref{#xtensa-x-elf,,xtensa*-*-elf}
3702 @uref{#xtensa-x-linux,,xtensa*-*-linux*}
3704 @uref{#windows,,Microsoft Windows}
3706 @uref{#x-x-cygwin,,*-*-cygwin}
3708 @uref{#x-x-mingw32,,*-*-mingw32}
3712 @uref{#older,,Older systems}
3717 @uref{#elf,,all ELF targets} (SVR4, Solaris 2, etc.)
3723 <!-- -------- host/target specific issues start here ---------------- -->
3726 @anchor{aarch64-x-x}
3727 @heading aarch64*-*-*
3728 Binutils pre 2.24 does not have support for selecting @option{-mabi} and
3729 does not support ILP32. If it is used to build GCC 4.9 or later, GCC will
3730 not support option @option{-mabi=ilp32}.
3732 To enable a workaround for the Cortex-A53 erratum number 835769 by default
3733 (for all CPUs regardless of -mcpu option given) at configure time use the
3734 @option{--enable-fix-cortex-a53-835769} option. This will enable the fix by
3735 default and can be explicitly disabled during compilation by passing the
3736 @option{-mno-fix-cortex-a53-835769} option. Conversely,
3737 @option{--disable-fix-cortex-a53-835769} will disable the workaround by
3738 default. The workaround is disabled by default if neither of
3739 @option{--enable-fix-cortex-a53-835769} or
3740 @option{--disable-fix-cortex-a53-835769} is given at configure time.
3742 To enable a workaround for the Cortex-A53 erratum number 843419 by default
3743 (for all CPUs regardless of -mcpu option given) at configure time use the
3744 @option{--enable-fix-cortex-a53-843419} option. This workaround is applied at
3745 link time. Enabling the workaround will cause GCC to pass the relevant option
3746 to the linker. It can be explicitly disabled during compilation by passing the
3747 @option{-mno-fix-cortex-a53-843419} option. Conversely,
3748 @option{--disable-fix-cortex-a53-843419} will disable the workaround by default.
3749 The workaround is disabled by default if neither of
3750 @option{--enable-fix-cortex-a53-843419} or
3751 @option{--disable-fix-cortex-a53-843419} is given at configure time.
3753 To enable Branch Target Identification Mechanism and Return Address Signing by
3754 default at configure time use the @option{--enable-standard-branch-protection}
3755 option. This is equivalent to having @option{-mbranch-protection=standard}
3756 during compilation. This can be explicitly disabled during compilation by
3757 passing the @option{-mbranch-protection=none} option which turns off all
3758 types of branch protections. Conversely,
3759 @option{--disable-standard-branch-protection} will disable both the
3760 protections by default. This mechanism is turned off by default if neither
3761 of the options are given at configure time.
3768 This section contains general configuration information for all
3769 Alpha-based platforms using ELF@. In addition to reading this
3770 section, please read all other sections that match your target.
3775 @anchor{amd64-x-solaris2}
3776 @heading amd64-*-solaris2*
3777 This is a synonym for @samp{x86_64-*-solaris2*}.
3782 @anchor{amdgcn-x-amdhsa}
3783 @heading amdgcn-*-amdhsa
3786 Instead of GNU Binutils, you will need to install LLVM 6, or later, and copy
3787 @file{bin/llvm-mc} to @file{amdgcn-amdhsa/bin/as},
3788 @file{bin/lld} to @file{amdgcn-amdhsa/bin/ld},
3789 @file{bin/llvm-nm} to @file{amdgcn-amdhsa/bin/nm}, and
3790 @file{bin/llvm-ar} to both @file{bin/amdgcn-amdhsa-ar} and
3791 @file{bin/amdgcn-amdhsa-ranlib}.
3793 Use Newlib (2019-01-16, or newer).
3795 To run the binaries, install the HSA Runtime from the
3796 @uref{https://rocm.github.io,,ROCm Platform}, and use
3797 @file{libexec/gcc/amdhsa-amdhsa/@var{version}/gcn-run} to launch them
3803 @anchor{arc-x-elf32}
3804 @heading arc-*-elf32
3806 Use @samp{configure --target=arc-elf32 --with-cpu=@var{cpu} --enable-languages="c,c++"}
3807 to configure GCC, with @var{cpu} being one of @samp{arc600}, @samp{arc601},
3813 @anchor{arc-linux-uclibc}
3814 @heading arc-linux-uclibc
3816 Use @samp{configure --target=arc-linux-uclibc --with-cpu=arc700 --enable-languages="c,c++"} to configure GCC@.
3823 ARM-family processors.
3825 Building the Ada frontend commonly fails (an infinite loop executing
3826 @code{xsinfo}) if the host compiler is GNAT 4.8. Host compilers built from the
3827 GNAT 4.6, 4.9 or 5 release branches are known to succeed.
3834 ATMEL AVR-family micro controllers. These are used in embedded
3835 applications. There are no standard Unix configurations.
3837 @xref{AVR Options,, AVR Options, gcc, Using the GNU Compiler
3841 See ``AVR Options'' in the main manual
3843 for the list of supported MCU types.
3845 Use @samp{configure --target=avr --enable-languages="c"} to configure GCC@.
3847 Further installation notes and other useful information about AVR tools
3848 can also be obtained from:
3852 @uref{http://www.nongnu.org/avr/,,http://www.nongnu.org/avr/}
3854 @uref{http://www.amelek.gda.pl/avr/,,http://www.amelek.gda.pl/avr/}
3857 The following error:
3859 Error: register required
3862 indicates that you should upgrade to a newer version of the binutils.
3869 The Blackfin processor, an Analog Devices DSP.
3871 @xref{Blackfin Options,, Blackfin Options, gcc, Using the GNU Compiler
3875 See ``Blackfin Options'' in the main manual
3878 More information, and a version of binutils with support for this processor,
3879 are available at @uref{https://sourceforge.net/projects/adi-toolchain/}.
3886 The CR16 CompactRISC architecture is a 16-bit architecture. This
3887 architecture is used in embedded applications.
3890 @xref{CR16 Options,, CR16 Options, gcc, Using and Porting the GNU Compiler
3895 See ``CR16 Options'' in the main manual for a list of CR16-specific options.
3898 Use @samp{configure --target=cr16-elf --enable-languages=c,c++} to configure
3899 GCC@ for building a CR16 elf cross-compiler.
3901 Use @samp{configure --target=cr16-uclinux --enable-languages=c,c++} to
3902 configure GCC@ for building a CR16 uclinux cross-compiler.
3909 CRIS is a CPU architecture in Axis Communications systems-on-a-chip, for
3910 example the ETRAX series. These are used in embedded applications.
3913 @xref{CRIS Options,, CRIS Options, gcc, Using the GNU Compiler
3917 See ``CRIS Options'' in the main manual
3919 for a list of CRIS-specific options.
3921 Use @samp{configure --target=cris-elf} to configure GCC@ for building
3922 a cross-compiler for CRIS.
3928 Please have a look at the @uref{binaries.html,,binaries page}.
3930 You cannot install GCC by itself on MSDOS; it will not compile under
3931 any MSDOS compiler except itself. You need to get the complete
3932 compilation package DJGPP, which includes binaries as well as sources,
3933 and includes all the necessary compilation tools and libraries.
3938 @anchor{epiphany-x-elf}
3939 @heading epiphany-*-elf
3941 This configuration is intended for embedded systems.
3946 @anchor{x-x-freebsd}
3947 @heading *-*-freebsd*
3948 In order to better utilize FreeBSD base system functionality and match
3949 the configuration of the system compiler, GCC 4.5 and above as well as
3950 GCC 4.4 past 2010-06-20 leverage SSP support in libc (which is present
3951 on FreeBSD 7 or later) and the use of @code{__cxa_atexit} by default
3952 (on FreeBSD 6 or later). The use of @code{dl_iterate_phdr} inside
3953 @file{libgcc_s.so.1} and boehm-gc (on FreeBSD 7 or later) is enabled
3954 by GCC 4.5 and above.
3956 We support FreeBSD using the ELF file format with DWARF 2 debugging
3957 for all CPU architectures. You may use @option{-gstabs} instead of
3958 @option{-g}, if you really want the old debugging format. There are
3959 no known issues with mixing object files and libraries with different
3960 debugging formats. Otherwise, this release of GCC should now match
3961 more of the configuration used in the stock FreeBSD configuration of
3962 GCC@. In particular, @option{--enable-threads} is now configured by
3963 default. However, as a general user, do not attempt to replace the
3964 system compiler with this release. Known to bootstrap and check with
3965 good results on FreeBSD 7.2-STABLE@. In the past, known to bootstrap
3966 and check with good results on FreeBSD 3.0, 3.4, 4.0, 4.2, 4.3, 4.4,
3967 4.5, 4.8, 4.9 and 5-CURRENT@.
3969 The version of binutils installed in @file{/usr/bin} probably works
3970 with this release of GCC@. Bootstrapping against the latest GNU
3971 binutils and/or the version found in @file{/usr/ports/devel/binutils} has
3972 been known to enable additional features and improve overall testsuite
3973 results. However, it is currently known that boehm-gc may not configure
3974 properly on FreeBSD prior to the FreeBSD 7.0 release with GNU binutils
3983 This configuration is intended for embedded systems.
3990 Renesas H8/300 series of processors.
3992 Please have a look at the @uref{binaries.html,,binaries page}.
3994 The calling convention and structure layout has changed in release 2.6.
3995 All code must be recompiled. The calling convention now passes the
3996 first three arguments in function calls in registers. Structures are no
3997 longer a multiple of 2 bytes.
4002 @anchor{hppa-hp-hpux}
4003 @heading hppa*-hp-hpux*
4004 Support for HP-UX version 9 and older was discontinued in GCC 3.4.
4006 We require using gas/binutils on all hppa platforms. Version 2.19 or
4007 later is recommended.
4009 It may be helpful to configure GCC with the
4010 @uref{./configure.html#with-gnu-as,,@option{--with-gnu-as}} and
4011 @option{--with-as=@dots{}} options to ensure that GCC can find GAS@.
4013 The HP assembler should not be used with GCC. It is rarely tested and may
4014 not work. It shouldn't be used with any languages other than C due to its
4017 Specifically, @option{-g} does not work (HP-UX uses a peculiar debugging
4018 format which GCC does not know about). It also inserts timestamps
4019 into each object file it creates, causing the 3-stage comparison test to
4020 fail during a bootstrap. You should be able to continue by saying
4021 @samp{make all-host all-target} after getting the failure from @samp{make}.
4023 Various GCC features are not supported. For example, it does not support weak
4024 symbols or alias definitions. As a result, explicit template instantiations
4025 are required when using C++. This makes it difficult if not impossible to
4026 build many C++ applications.
4028 There are two default scheduling models for instructions. These are
4029 PROCESSOR_7100LC and PROCESSOR_8000. They are selected from the pa-risc
4030 architecture specified for the target machine when configuring.
4031 PROCESSOR_8000 is the default. PROCESSOR_7100LC is selected when
4032 the target is a @samp{hppa1*} machine.
4034 The PROCESSOR_8000 model is not well suited to older processors. Thus,
4035 it is important to completely specify the machine architecture when
4036 configuring if you want a model other than PROCESSOR_8000. The macro
4037 TARGET_SCHED_DEFAULT can be defined in BOOT_CFLAGS if a different
4038 default scheduling model is desired.
4040 As of GCC 4.0, GCC uses the UNIX 95 namespace for HP-UX 10.10
4041 through 11.00, and the UNIX 98 namespace for HP-UX 11.11 and later.
4042 This namespace change might cause problems when bootstrapping with
4043 an earlier version of GCC or the HP compiler as essentially the same
4044 namespace is required for an entire build. This problem can be avoided
4045 in a number of ways. With HP cc, @env{UNIX_STD} can be set to @samp{95}
4046 or @samp{98}. Another way is to add an appropriate set of predefines
4047 to @env{CC}. The description for the @option{munix=} option contains
4048 a list of the predefines used with each standard.
4050 More specific information to @samp{hppa*-hp-hpux*} targets follows.
4055 @anchor{hppa-hp-hpux10}
4056 @heading hppa*-hp-hpux10
4057 For hpux10.20, we @emph{highly} recommend you pick up the latest sed patch
4058 @code{PHCO_19798} from HP@.
4060 The C++ ABI has changed incompatibly in GCC 4.0. COMDAT subspaces are
4061 used for one-only code and data. This resolves many of the previous
4062 problems in using C++ on this target. However, the ABI is not compatible
4063 with the one implemented under HP-UX 11 using secondary definitions.
4068 @anchor{hppa-hp-hpux11}
4069 @heading hppa*-hp-hpux11
4070 GCC 3.0 and up support HP-UX 11. GCC 2.95.x is not supported and cannot
4071 be used to compile GCC 3.0 and up.
4073 The libffi library haven't been ported to 64-bit HP-UX@ and doesn't build.
4075 Refer to @uref{binaries.html,,binaries} for information about obtaining
4076 precompiled GCC binaries for HP-UX@. Precompiled binaries must be obtained
4077 to build the Ada language as it cannot be bootstrapped using C@. Ada is
4078 only available for the 32-bit PA-RISC runtime.
4080 Starting with GCC 3.4 an ISO C compiler is required to bootstrap. The
4081 bundled compiler supports only traditional C; you will need either HP's
4082 unbundled compiler, or a binary distribution of GCC@.
4084 It is possible to build GCC 3.3 starting with the bundled HP compiler,
4085 but the process requires several steps. GCC 3.3 can then be used to
4086 build later versions.
4088 There are several possible approaches to building the distribution.
4089 Binutils can be built first using the HP tools. Then, the GCC
4090 distribution can be built. The second approach is to build GCC
4091 first using the HP tools, then build binutils, then rebuild GCC@.
4092 There have been problems with various binary distributions, so it
4093 is best not to start from a binary distribution.
4095 On 64-bit capable systems, there are two distinct targets. Different
4096 installation prefixes must be used if both are to be installed on
4097 the same system. The @samp{hppa[1-2]*-hp-hpux11*} target generates code
4098 for the 32-bit PA-RISC runtime architecture and uses the HP linker.
4099 The @samp{hppa64-hp-hpux11*} target generates 64-bit code for the
4100 PA-RISC 2.0 architecture.
4102 The script config.guess now selects the target type based on the compiler
4103 detected during configuration. You must define @env{PATH} or @env{CC} so
4104 that configure finds an appropriate compiler for the initial bootstrap.
4105 When @env{CC} is used, the definition should contain the options that are
4106 needed whenever @env{CC} is used.
4108 Specifically, options that determine the runtime architecture must be
4109 in @env{CC} to correctly select the target for the build. It is also
4110 convenient to place many other compiler options in @env{CC}. For example,
4111 @env{CC="cc -Ac +DA2.0W -Wp,-H16376 -D_CLASSIC_TYPES -D_HPUX_SOURCE"}
4112 can be used to bootstrap the GCC 3.3 branch with the HP compiler in
4113 64-bit K&R/bundled mode. The @option{+DA2.0W} option will result in
4114 the automatic selection of the @samp{hppa64-hp-hpux11*} target. The
4115 macro definition table of cpp needs to be increased for a successful
4116 build with the HP compiler. _CLASSIC_TYPES and _HPUX_SOURCE need to
4117 be defined when building with the bundled compiler, or when using the
4118 @option{-Ac} option. These defines aren't necessary with @option{-Ae}.
4120 It is best to explicitly configure the @samp{hppa64-hp-hpux11*} target
4121 with the @option{--with-ld=@dots{}} option. This overrides the standard
4122 search for ld. The two linkers supported on this target require different
4123 commands. The default linker is determined during configuration. As a
4124 result, it's not possible to switch linkers in the middle of a GCC build.
4125 This has been reported to sometimes occur in unified builds of binutils
4128 A recent linker patch must be installed for the correct operation of
4129 GCC 3.3 and later. @code{PHSS_26559} and @code{PHSS_24304} are the
4130 oldest linker patches that are known to work. They are for HP-UX
4131 11.00 and 11.11, respectively. @code{PHSS_24303}, the companion to
4132 @code{PHSS_24304}, might be usable but it hasn't been tested. These
4133 patches have been superseded. Consult the HP patch database to obtain
4134 the currently recommended linker patch for your system.
4136 The patches are necessary for the support of weak symbols on the
4137 32-bit port, and for the running of initializers and finalizers. Weak
4138 symbols are implemented using SOM secondary definition symbols. Prior
4139 to HP-UX 11, there are bugs in the linker support for secondary symbols.
4140 The patches correct a problem of linker core dumps creating shared
4141 libraries containing secondary symbols, as well as various other
4142 linking issues involving secondary symbols.
4144 GCC 3.3 uses the ELF DT_INIT_ARRAY and DT_FINI_ARRAY capabilities to
4145 run initializers and finalizers on the 64-bit port. The 32-bit port
4146 uses the linker @option{+init} and @option{+fini} options for the same
4147 purpose. The patches correct various problems with the +init/+fini
4148 options, including program core dumps. Binutils 2.14 corrects a
4149 problem on the 64-bit port resulting from HP's non-standard use of
4150 the .init and .fini sections for array initializers and finalizers.
4152 Although the HP and GNU linkers are both supported for the
4153 @samp{hppa64-hp-hpux11*} target, it is strongly recommended that the
4154 HP linker be used for link editing on this target.
4156 At this time, the GNU linker does not support the creation of long
4157 branch stubs. As a result, it cannot successfully link binaries
4158 containing branch offsets larger than 8 megabytes. In addition,
4159 there are problems linking shared libraries, linking executables
4160 with @option{-static}, and with dwarf2 unwind and exception support.
4161 It also doesn't provide stubs for internal calls to global functions
4162 in shared libraries, so these calls cannot be overloaded.
4164 The HP dynamic loader does not support GNU symbol versioning, so symbol
4165 versioning is not supported. It may be necessary to disable symbol
4166 versioning with @option{--disable-symvers} when using GNU ld.
4168 POSIX threads are the default. The optional DCE thread library is not
4169 supported, so @option{--enable-threads=dce} does not work.
4174 @anchor{x-x-linux-gnu}
4175 @heading *-*-linux-gnu
4176 The @code{.init_array} and @code{.fini_array} sections are enabled
4177 unconditionally which requires at least glibc 2.1 and binutils 2.12.
4179 Versions of libstdc++-v3 starting with 3.2.1 require bug fixes present
4180 in glibc 2.2.5 and later. More information is available in the
4181 libstdc++-v3 documentation.
4186 @anchor{ix86-x-linux}
4187 @heading i?86-*-linux*
4188 As of GCC 3.3, binutils 2.13.1 or later is required for this platform.
4189 See @uref{https://gcc.gnu.org/PR10877,,bug 10877} for more information.
4191 If you receive Signal 11 errors when building on GNU/Linux, then it is
4192 possible you have a hardware problem. Further information on this can be
4193 found on @uref{https://www.bitwizard.nl/sig11/,,www.bitwizard.nl}.
4198 @anchor{ix86-x-solaris2}
4199 @heading i?86-*-solaris2*
4200 Use this for Solaris 11.3 or later on x86 and x86-64 systems. Starting
4201 with GCC 4.7, there is also a 64-bit @samp{amd64-*-solaris2*} or
4202 @samp{x86_64-*-solaris2*} configuration that corresponds to
4203 @samp{sparcv9-sun-solaris2*}.
4205 It is recommended that you configure GCC to use the GNU assembler. The
4206 versions included in Solaris 11.3, from GNU binutils 2.23.1 or
4207 newer (available as @file{/usr/bin/gas} and
4208 @file{/usr/gnu/bin/as}), work fine. The current version, from GNU
4209 binutils 2.34, is known to work. Recent versions of the Solaris assembler in
4210 @file{/usr/bin/as} work almost as well, though.
4212 For linking, the Solaris linker is preferred. If you want to use the GNU
4213 linker instead, the version in Solaris 11.3, from GNU binutils 2.23.1 or
4214 newer (in @file{/usr/gnu/bin/ld} and @file{/usr/bin/gld}), works,
4215 as does the latest version, from GNU binutils 2.34.
4217 To use GNU @command{as}, configure with the options
4218 @option{--with-gnu-as --with-as=@//usr/@/gnu/@/bin/@/as}. It may be necessary
4219 to configure with @option{--without-gnu-ld --with-ld=@//usr/@/ccs/@/bin/@/ld} to
4220 guarantee use of Solaris @command{ld}.
4221 @c FIXME: why --without-gnu-ld --with-ld?
4226 @anchor{ia64-x-linux}
4227 @heading ia64-*-linux
4228 IA-64 processor (also known as IPF, or Itanium Processor Family)
4231 If you are using the installed system libunwind library with
4232 @option{--with-system-libunwind}, then you must use libunwind 0.98 or
4238 @anchor{ia64-x-hpux}
4239 @heading ia64-*-hpux*
4240 Building GCC on this target requires the GNU Assembler. The bundled HP
4241 assembler will not work. To prevent GCC from using the wrong assembler,
4242 the option @option{--with-gnu-as} may be necessary.
4244 The GCC libunwind library has not been ported to HPUX@. This means that for
4245 GCC versions 3.2.3 and earlier, @option{--enable-libunwind-exceptions}
4246 is required to build GCC@. For GCC 3.3 and later, this is the default.
4247 For gcc 3.4.3 and later, @option{--enable-libunwind-exceptions} is
4248 removed and the system libunwind library will always be used.
4252 <!-- rs6000-ibm-aix*, powerpc-ibm-aix* -->
4256 Support for AIX version 3 and older was discontinued in GCC 3.4.
4257 Support for AIX version 4.2 and older was discontinued in GCC 4.5.
4259 ``out of memory'' bootstrap failures may indicate a problem with
4260 process resource limits (ulimit). Hard limits are configured in the
4261 @file{/etc/security/limits} system configuration file.
4263 GCC 4.9 and above require a C++ compiler for bootstrap. IBM VAC++ / xlC
4264 cannot bootstrap GCC. xlc can bootstrap an older version of GCC and
4265 G++ can bootstrap recent releases of GCC.
4267 GCC can bootstrap with recent versions of IBM XLC, but bootstrapping
4268 with an earlier release of GCC is recommended. Bootstrapping with XLC
4269 requires a larger data segment, which can be enabled through the
4270 @var{LDR_CNTRL} environment variable, e.g.,
4273 % LDR_CNTRL=MAXDATA=0x50000000
4277 One can start with a pre-compiled version of GCC to build from
4278 sources. One may delete GCC's ``fixed'' header files when starting
4279 with a version of GCC built for an earlier release of AIX.
4281 To speed up the configuration phases of bootstrapping and installing GCC,
4282 one may use GNU Bash instead of AIX @command{/bin/sh}, e.g.,
4285 % CONFIG_SHELL=/opt/freeware/bin/bash
4286 % export CONFIG_SHELL
4289 and then proceed as described in @uref{build.html,,the build
4290 instructions}, where we strongly recommend specifying an absolute path
4291 to invoke @var{srcdir}/configure.
4293 Because GCC on AIX is built as a 32-bit executable by default,
4294 (although it can generate 64-bit programs) the GMP and MPFR libraries
4295 required by gfortran must be 32-bit libraries. Building GMP and MPFR
4296 as static archive libraries works better than shared libraries.
4298 Errors involving @code{alloca} when building GCC generally are due
4299 to an incorrect definition of @code{CC} in the Makefile or mixing files
4300 compiled with the native C compiler and GCC@. During the stage1 phase of
4301 the build, the native AIX compiler @strong{must} be invoked as @command{cc}
4302 (not @command{xlc}). Once @command{configure} has been informed of
4303 @command{xlc}, one needs to use @samp{make distclean} to remove the
4304 configure cache files and ensure that @env{CC} environment variable
4305 does not provide a definition that will confuse @command{configure}.
4306 If this error occurs during stage2 or later, then the problem most likely
4307 is the version of Make (see above).
4309 The native @command{as} and @command{ld} are recommended for
4310 bootstrapping on AIX@. The GNU Assembler, GNU Linker, and GNU
4311 Binutils version 2.20 is the minimum level that supports bootstrap on
4312 AIX 5@. The GNU Assembler has not been updated to support AIX 6@ or
4313 AIX 7. The native AIX tools do interoperate with GCC@.
4315 AIX 7.1 added partial support for DWARF debugging, but full support
4316 requires AIX 7.1 TL03 SP7 that supports additional DWARF sections and
4317 fixes a bug in the assembler. AIX 7.1 TL03 SP5 distributed a version
4318 of libm.a missing important symbols; a fix for IV77796 will be
4321 AIX 5.3 TL10, AIX 6.1 TL05 and AIX 7.1 TL00 introduced an AIX
4322 assembler change that sometimes produces corrupt assembly files
4323 causing AIX linker errors. The bug breaks GCC bootstrap on AIX and
4324 can cause compilation failures with existing GCC installations. An
4325 AIX iFix for AIX 5.3 is available (APAR IZ98385 for AIX 5.3 TL10, APAR
4326 IZ98477 for AIX 5.3 TL11 and IZ98134 for AIX 5.3 TL12). AIX 5.3 TL11 SP8,
4327 AIX 5.3 TL12 SP5, AIX 6.1 TL04 SP11, AIX 6.1 TL05 SP7, AIX 6.1 TL06 SP6,
4328 AIX 6.1 TL07 and AIX 7.1 TL01 should include the fix.
4330 Building @file{libstdc++.a} requires a fix for an AIX Assembler bug
4331 APAR IY26685 (AIX 4.3) or APAR IY25528 (AIX 5.1). It also requires a
4332 fix for another AIX Assembler bug and a co-dependent AIX Archiver fix
4333 referenced as APAR IY53606 (AIX 5.2) or as APAR IY54774 (AIX 5.1)
4335 @anchor{TransferAixShobj}
4336 @samp{libstdc++} in GCC 3.4 increments the major version number of the
4337 shared object and GCC installation places the @file{libstdc++.a}
4338 shared library in a common location which will overwrite the and GCC
4339 3.3 version of the shared library. Applications either need to be
4340 re-linked against the new shared library or the GCC 3.1 and GCC 3.3
4341 versions of the @samp{libstdc++} shared object needs to be available
4342 to the AIX runtime loader. The GCC 3.1 @samp{libstdc++.so.4}, if
4343 present, and GCC 3.3 @samp{libstdc++.so.5} shared objects can be
4344 installed for runtime dynamic loading using the following steps to set
4345 the @samp{F_LOADONLY} flag in the shared object for @emph{each}
4346 multilib @file{libstdc++.a} installed:
4348 Extract the shared objects from the currently installed
4349 @file{libstdc++.a} archive:
4351 % ar -x libstdc++.a libstdc++.so.4 libstdc++.so.5
4354 Enable the @samp{F_LOADONLY} flag so that the shared object will be
4355 available for runtime dynamic loading, but not linking:
4357 % strip -e libstdc++.so.4 libstdc++.so.5
4360 Archive the runtime-only shared object in the GCC 3.4
4361 @file{libstdc++.a} archive:
4363 % ar -q libstdc++.a libstdc++.so.4 libstdc++.so.5
4367 @uref{./configure.html#WithAixSoname,,@option{--with-aix-soname=svr4}}
4368 configure option may drop the need for this procedure for libraries that
4371 Linking executables and shared libraries may produce warnings of
4372 duplicate symbols. The assembly files generated by GCC for AIX always
4373 have included multiple symbol definitions for certain global variable
4374 and function declarations in the original program. The warnings should
4375 not prevent the linker from producing a correct library or runnable
4378 AIX 4.3 utilizes a ``large format'' archive to support both 32-bit and
4379 64-bit object modules. The routines provided in AIX 4.3.0 and AIX 4.3.1
4380 to parse archive libraries did not handle the new format correctly.
4381 These routines are used by GCC and result in error messages during
4382 linking such as ``not a COFF file''. The version of the routines shipped
4383 with AIX 4.3.1 should work for a 32-bit environment. The @option{-g}
4384 option of the archive command may be used to create archives of 32-bit
4385 objects using the original ``small format''. A correct version of the
4386 routines is shipped with AIX 4.3.2 and above.
4388 Some versions of the AIX binder (linker) can fail with a relocation
4389 overflow severe error when the @option{-bbigtoc} option is used to link
4390 GCC-produced object files into an executable that overflows the TOC@. A fix
4391 for APAR IX75823 (OVERFLOW DURING LINK WHEN USING GCC AND -BBIGTOC) is
4392 available from IBM Customer Support and from its
4393 @uref{https://techsupport.services.ibm.com/,,techsupport.services.ibm.com}
4394 website as PTF U455193.
4396 The AIX 4.3.2.1 linker (bos.rte.bind_cmds Level 4.3.2.1) will dump core
4397 with a segmentation fault when invoked by any version of GCC@. A fix for
4398 APAR IX87327 is available from IBM Customer Support and from its
4399 @uref{https://techsupport.services.ibm.com/,,techsupport.services.ibm.com}
4400 website as PTF U461879. This fix is incorporated in AIX 4.3.3 and above.
4402 The initial assembler shipped with AIX 4.3.0 generates incorrect object
4403 files. A fix for APAR IX74254 (64BIT DISASSEMBLED OUTPUT FROM COMPILER FAILS
4404 TO ASSEMBLE/BIND) is available from IBM Customer Support and from its
4405 @uref{https://techsupport.services.ibm.com/,,techsupport.services.ibm.com}
4406 website as PTF U453956. This fix is incorporated in AIX 4.3.1 and above.
4408 AIX provides National Language Support (NLS)@. Compilers and assemblers
4409 use NLS to support locale-specific representations of various data
4410 formats including floating-point numbers (e.g., @samp{.} vs @samp{,} for
4411 separating decimal fractions). There have been problems reported where
4412 GCC does not produce the same floating-point formats that the assembler
4413 expects. If one encounters this problem, set the @env{LANG}
4414 environment variable to @samp{C} or @samp{En_US}.
4416 A default can be specified with the @option{-mcpu=@var{cpu_type}}
4417 switch and using the configure option @option{--with-cpu-@var{cpu_type}}.
4422 @anchor{iq2000-x-elf}
4423 @heading iq2000-*-elf
4424 Vitesse IQ2000 processors. These are used in embedded
4425 applications. There are no standard Unix configurations.
4432 Lattice Mico32 processor.
4433 This configuration is intended for embedded systems.
4438 @anchor{lm32-x-uclinux}
4439 @heading lm32-*-uclinux
4440 Lattice Mico32 processor.
4441 This configuration is intended for embedded systems running uClinux.
4448 LoongArch processor.
4449 The following LoongArch targets are available:
4451 @item loongarch64-linux-gnu*
4452 LoongArch processor running GNU/Linux. This target triplet may be coupled
4453 with a small set of possible suffixes to identify their default ABI type:
4456 Uses @code{lp64d/base} ABI by default.
4458 Uses @code{lp64f/base} ABI by default.
4460 Uses @code{lp64s/base} ABI by default.
4463 @item loongarch64-linux-gnu
4464 Same as @code{loongarch64-linux-gnuf64}, but may be used with
4465 @option{--with-abi=*} to configure the default ABI type.
4468 More information about LoongArch can be found at
4469 @uref{https://github.com/loongson/LoongArch-Documentation}.
4476 Renesas M32C processor.
4477 This configuration is intended for embedded systems.
4484 Renesas M32R processor.
4485 This configuration is intended for embedded systems.
4493 @samp{m68k-*-elf*}, @samp{m68k-*-rtems}, @samp{m68k-*-uclinux} and
4495 build libraries for both M680x0 and ColdFire processors. If you only
4496 need the M680x0 libraries, you can omit the ColdFire ones by passing
4497 @option{--with-arch=m68k} to @command{configure}. Alternatively, you
4498 can omit the M680x0 libraries by passing @option{--with-arch=cf} to
4499 @command{configure}. These targets default to 5206 or 5475 code as
4500 appropriate for the target system when
4501 configured with @option{--with-arch=cf} and 68020 code otherwise.
4503 The @samp{m68k-*-netbsd} and
4504 @samp{m68k-*-openbsd} targets also support the @option{--with-arch}
4505 option. They will generate ColdFire CFV4e code when configured with
4506 @option{--with-arch=cf} and 68020 code otherwise.
4508 You can override the default processors listed above by configuring
4509 with @option{--with-cpu=@var{target}}. This @var{target} can either
4510 be a @option{-mcpu} argument or one of the following values:
4511 @samp{m68000}, @samp{m68010}, @samp{m68020}, @samp{m68030},
4512 @samp{m68040}, @samp{m68060}, @samp{m68020-40} and @samp{m68020-60}.
4514 GCC requires at least binutils version 2.17 on these targets.
4519 @anchor{m68k-x-uclinux}
4520 @heading m68k-*-uclinux
4521 GCC 4.3 changed the uClinux configuration so that it uses the
4522 @samp{m68k-linux-gnu} ABI rather than the @samp{m68k-elf} ABI.
4523 It also added improved support for C++ and flat shared libraries,
4524 both of which were ABI changes.
4529 @anchor{microblaze-x-elf}
4530 @heading microblaze-*-elf
4531 Xilinx MicroBlaze processor.
4532 This configuration is intended for embedded systems.
4539 If on a MIPS system you get an error message saying ``does not have gp
4540 sections for all it's [sic] sectons [sic]'', don't worry about it. This
4541 happens whenever you use GAS with the MIPS linker, but there is not
4542 really anything wrong, and it is okay to use the output file. You can
4543 stop such warnings by installing the GNU linker.
4545 It would be nice to extend GAS to produce the gp tables, but they are
4546 optional, and there should not be a warning about their absence.
4548 The libstdc++ atomic locking routines for MIPS targets requires MIPS II
4549 and later. A patch went in just after the GCC 3.3 release to
4550 make @samp{mips*-*-*} use the generic implementation instead. You can also
4551 configure for @samp{mipsel-elf} as a workaround. The
4552 @samp{mips*-*-linux*} target continues to use the MIPS II routines. More
4553 work on this is expected in future releases.
4555 @c If you make --with-llsc the default for another target, please also
4556 @c update the description of the --with-llsc option.
4558 The built-in @code{__sync_*} functions are available on MIPS II and
4559 later systems and others that support the @samp{ll}, @samp{sc} and
4560 @samp{sync} instructions. This can be overridden by passing
4561 @option{--with-llsc} or @option{--without-llsc} when configuring GCC.
4562 Since the Linux kernel emulates these instructions if they are
4563 missing, the default for @samp{mips*-*-linux*} targets is
4564 @option{--with-llsc}. The @option{--with-llsc} and
4565 @option{--without-llsc} configure options may be overridden at compile
4566 time by passing the @option{-mllsc} or @option{-mno-llsc} options to
4569 MIPS systems check for division by zero (unless
4570 @option{-mno-check-zero-division} is passed to the compiler) by
4571 generating either a conditional trap or a break instruction. Using
4572 trap results in smaller code, but is only supported on MIPS II and
4573 later. Also, some versions of the Linux kernel have a bug that
4574 prevents trap from generating the proper signal (@code{SIGFPE}). To enable
4575 the use of break, use the @option{--with-divide=breaks}
4576 @command{configure} option when configuring GCC@. The default is to
4577 use traps on systems that support them.
4582 @anchor{moxie-x-elf}
4583 @heading moxie-*-elf
4584 The moxie processor.
4589 @anchor{msp430-x-elf}
4590 @heading msp430-*-elf*
4591 TI MSP430 processor.
4592 This configuration is intended for embedded systems.
4594 @samp{msp430-*-elf} is the standard configuration with most GCC
4595 features enabled by default.
4597 @samp{msp430-*-elfbare} is tuned for a bare-metal environment, and disables
4598 features related to shared libraries and other functionality not used for
4599 this device. This reduces code and data usage of the GCC libraries, resulting
4600 in a minimal run-time environment by default.
4602 Features disabled by default include:
4604 @item transactional memory
4611 @anchor{nds32le-x-elf}
4612 @heading nds32le-*-elf
4613 Andes NDS32 target in little endian mode.
4618 @anchor{nds32be-x-elf}
4619 @heading nds32be-*-elf
4620 Andes NDS32 target in big endian mode.
4625 @anchor{nvptx-x-none}
4626 @heading nvptx-*-none
4629 Instead of GNU binutils, you will need to install
4630 @uref{https://github.com/MentorEmbedded/nvptx-tools/,,nvptx-tools}.
4631 Tell GCC where to find it:
4632 @option{--with-build-time-tools=[install-nvptx-tools]/nvptx-none/bin}.
4634 You will need newlib 3.0 git revision
4635 cd31fbb2aea25f94d7ecedc9db16dfc87ab0c316 or later. It can be
4636 automatically built together with GCC@. For this, add a symbolic link
4637 to nvptx-newlib's @file{newlib} directory to the directory containing
4640 Use the @option{--disable-sjlj-exceptions} and
4641 @option{--enable-newlib-io-long-long} options when configuring.
4648 The OpenRISC 1000 32-bit processor with delay slots.
4649 This configuration is intended for embedded systems.
4654 @anchor{or1k-x-linux}
4655 @heading or1k-*-linux
4656 The OpenRISC 1000 32-bit processor with delay slots.
4661 @anchor{powerpc-x-x}
4662 @heading powerpc-*-*
4663 You can specify a default version for the @option{-mcpu=@var{cpu_type}}
4664 switch by using the configure option @option{--with-cpu-@var{cpu_type}}.
4666 You will need GNU binutils 2.20 or newer.
4671 @anchor{powerpc-x-darwin}
4672 @heading powerpc-*-darwin*
4673 PowerPC running Darwin (Mac OS X kernel).
4675 Pre-installed versions of Mac OS X may not include any developer tools,
4676 meaning that you will not be able to build GCC from source. Tool
4677 binaries are available at
4678 @uref{https://opensource.apple.com}.
4680 This version of GCC requires at least cctools-590.36. The
4681 cctools-590.36 package referenced from
4682 @uref{https://gcc.gnu.org/ml/gcc/2006-03/msg00507.html} will not work
4683 on systems older than 10.3.9 (aka darwin7.9.0).
4688 @anchor{powerpc-x-elf}
4689 @heading powerpc-*-elf
4690 PowerPC system in big endian mode, running System V.4.
4695 @anchor{powerpc-x-linux-gnu}
4696 @heading powerpc*-*-linux-gnu*
4697 PowerPC system in big endian mode running Linux.
4702 @anchor{powerpc-x-netbsd}
4703 @heading powerpc-*-netbsd*
4704 PowerPC system in big endian mode running NetBSD@.
4709 @anchor{powerpc-x-eabisim}
4710 @heading powerpc-*-eabisim
4711 Embedded PowerPC system in big endian mode for use in running under the
4717 @anchor{powerpc-x-eabi}
4718 @heading powerpc-*-eabi
4719 Embedded PowerPC system in big endian mode.
4724 @anchor{powerpcle-x-elf}
4725 @heading powerpcle-*-elf
4726 PowerPC system in little endian mode, running System V.4.
4731 @anchor{powerpcle-x-eabisim}
4732 @heading powerpcle-*-eabisim
4733 Embedded PowerPC system in little endian mode for use in running under
4739 @anchor{powerpcle-x-eabi}
4740 @heading powerpcle-*-eabi
4741 Embedded PowerPC system in little endian mode.
4748 The Renesas RL78 processor.
4749 This configuration is intended for embedded systems.
4754 @anchor{riscv32-x-elf}
4755 @heading riscv32-*-elf
4756 The RISC-V RV32 instruction set.
4757 This configuration is intended for embedded systems.
4758 This (and all other RISC-V) targets require the binutils 2.30 release.
4763 @anchor{riscv32-x-linux}
4764 @heading riscv32-*-linux
4765 The RISC-V RV32 instruction set running GNU/Linux.
4766 This (and all other RISC-V) targets require the binutils 2.30 release.
4771 @anchor{riscv64-x-elf}
4772 @heading riscv64-*-elf
4773 The RISC-V RV64 instruction set.
4774 This configuration is intended for embedded systems.
4775 This (and all other RISC-V) targets require the binutils 2.30 release.
4780 @anchor{riscv64-x-linux}
4781 @heading riscv64-*-linux
4782 The RISC-V RV64 instruction set running GNU/Linux.
4783 This (and all other RISC-V) targets require the binutils 2.30 release.
4790 The Renesas RX processor.
4795 @anchor{s390-x-linux}
4796 @heading s390-*-linux*
4797 S/390 system running GNU/Linux for S/390@.
4802 @anchor{s390x-x-linux}
4803 @heading s390x-*-linux*
4804 zSeries system (64-bit) running GNU/Linux for zSeries@.
4809 @anchor{s390x-ibm-tpf}
4810 @heading s390x-ibm-tpf*
4811 zSeries system (64-bit) running TPF@. This platform is
4812 supported as cross-compilation target only.
4817 @c Please use Solaris 2 to refer to all release of Solaris, starting
4818 @c with 2.0 until 2.6, 7, 8, etc. Solaris 1 was a marketing name for
4819 @c SunOS 4 releases which we don't use to avoid confusion. Solaris
4820 @c alone is too unspecific and must be avoided.
4821 @anchor{x-x-solaris2}
4822 @heading *-*-solaris2*
4823 Support for Solaris 10 has been removed in GCC 10. Support for Solaris
4824 9 has been removed in GCC 5. Support for Solaris 8 has been removed in
4825 GCC 4.8. Support for Solaris 7 has been removed in GCC 4.6.
4827 Solaris 11.3 provides GCC 4.5.2, 4.7.3, and 4.8.2 as
4828 @command{/usr/gcc/4.5/bin/gcc} or similar. Newer Solaris versions
4829 provide one or more of GCC 5, 7, and 9. Alternatively,
4830 you can install a pre-built GCC to bootstrap and install GCC. See the
4831 @uref{binaries.html,,binaries page} for details.
4833 The Solaris 2 @command{/bin/sh} will often fail to configure
4834 @samp{libstdc++-v3}. We therefore recommend using the
4835 following initial sequence of commands
4838 % CONFIG_SHELL=/bin/ksh
4839 % export CONFIG_SHELL
4843 and proceed as described in @uref{configure.html,,the configure instructions}.
4844 In addition we strongly recommend specifying an absolute path to invoke
4845 @command{@var{srcdir}/configure}.
4847 In Solaris 11, you need to check for @code{system/header},
4848 @code{system/linker}, and @code{developer/assembler} packages.
4850 Trying to use the linker and other tools in
4851 @file{/usr/ucb} to install GCC has been observed to cause trouble.
4852 For example, the linker may hang indefinitely. The fix is to remove
4853 @file{/usr/ucb} from your @env{PATH}.
4855 The build process works more smoothly with the legacy Solaris tools so, if you
4856 have @file{/usr/xpg4/bin} in your @env{PATH}, we recommend that you place
4857 @file{/usr/bin} before @file{/usr/xpg4/bin} for the duration of the build.
4859 We recommend the use of the Solaris assembler or the GNU assembler, in
4860 conjunction with the Solaris linker. The GNU @command{as}
4861 versions included in Solaris 11.3,
4862 from GNU binutils 2.23.1 or newer (in @file{/usr/bin/gas} and
4863 @file{/usr/gnu/bin/as}), are known to work.
4864 The current version, from GNU binutils 2.34,
4865 is known to work as well. Note that your mileage may vary
4866 if you use a combination of the GNU tools and the Solaris tools: while the
4867 combination GNU @command{as} + Solaris @command{ld} should reasonably work,
4868 the reverse combination Solaris @command{as} + GNU @command{ld} may fail to
4869 build or cause memory corruption at runtime in some cases for C++ programs.
4871 GNU @command{ld} usually works as well. Again, the current
4872 version (2.34) is known to work, but generally lacks platform specific
4873 features, so better stay with Solaris @command{ld}. To use the LTO linker
4874 plugin (@option{-fuse-linker-plugin}) with GNU @command{ld}, GNU
4875 binutils @emph{must} be configured with @option{--enable-largefile}.
4877 To enable symbol versioning in @samp{libstdc++} with the Solaris linker,
4878 you need to have any version of GNU @command{c++filt}, which is part of
4879 GNU binutils. @samp{libstdc++} symbol versioning will be disabled if no
4880 appropriate version is found. Solaris @command{c++filt} from the Solaris
4881 Studio compilers does @emph{not} work.
4883 In order to build the GNU D compiler, GDC, a working @samp{libphobos} is
4884 needed. That library wasn't built by default in GCC 9--11 on SPARC, or
4885 on x86 when the Solaris assembler is used, but can be enabled by
4886 configuring with @option{--enable-libphobos}. Also, GDC 9.4.0 is
4887 required on x86, while GDC 9.3.0 is known to work on SPARC.
4889 The versions of the GNU Multiple Precision Library (GMP), the MPFR
4890 library and the MPC library bundled with Solaris 11.3 and later are
4891 usually recent enough to match GCC's requirements. There are two
4896 While the version of the GMP library in Solaris 11.3 works with GCC, you
4897 need to configure with @option{--with-gmp-include=/usr/include/gmp}.
4900 The version of the MPFR libary included in Solaris 11.3 is too old; you
4901 need to provide a more recent one.
4910 This section contains general configuration information for all
4911 SPARC-based platforms. In addition to reading this section, please
4912 read all other sections that match your target.
4914 Newer versions of the GNU Multiple Precision Library (GMP), the MPFR
4915 library and the MPC library are known to be miscompiled by earlier
4916 versions of GCC on these platforms. We therefore recommend the use
4917 of the exact versions of these libraries listed as minimal versions
4918 in @uref{prerequisites.html,,the prerequisites}.
4923 @anchor{sparc-sun-solaris2}
4924 @heading sparc-sun-solaris2*
4925 When GCC is configured to use GNU binutils 2.14 or later, the binaries
4926 produced are smaller than the ones produced using Solaris native tools;
4927 this difference is quite significant for binaries containing debugging
4930 Starting with Solaris 7, the operating system is capable of executing
4931 64-bit SPARC V9 binaries. GCC 3.1 and later properly supports
4932 this; the @option{-m64} option enables 64-bit code generation.
4933 However, if all you want is code tuned for the UltraSPARC CPU, you
4934 should try the @option{-mtune=ultrasparc} option instead, which produces
4935 code that, unlike full 64-bit code, can still run on non-UltraSPARC
4938 When configuring the GNU Multiple Precision Library (GMP), the MPFR
4939 library or the MPC library on a Solaris 7 or later system, the canonical
4940 target triplet must be specified as the @command{build} parameter on the
4941 configure line. This target triplet can be obtained by invoking @command{./config.guess} in the toplevel source directory of GCC (and
4942 not that of GMP or MPFR or MPC). For example on a Solaris 11 system:
4945 % ./configure --build=sparc-sun-solaris2.11 --prefix=xxx
4951 @anchor{sparc-x-linux}
4952 @heading sparc-*-linux*
4957 @anchor{sparc64-x-solaris2}
4958 @heading sparc64-*-solaris2*
4959 When configuring a 64-bit-default GCC on Solaris/SPARC, you must use a
4960 build compiler that generates 64-bit code, either by default or by
4961 specifying @samp{CC='gcc -m64' CXX='gcc-m64'} to @command{configure}.
4962 Additionally, you @emph{must} pass @option{--build=sparc64-sun-solaris2.11}
4963 or @option{--build=sparcv9-sun-solaris2.11} because @file{config.guess}
4964 misdetects this situation, which can cause build failures.
4966 When configuring the GNU Multiple Precision Library (GMP), the MPFR
4967 library or the MPC library, the canonical target triplet must be specified
4968 as the @command{build} parameter on the configure line. For example
4969 on a Solaris 11 system:
4972 % ./configure --build=sparc64-sun-solaris2.11 --prefix=xxx
4978 @anchor{sparcv9-x-solaris2}
4979 @heading sparcv9-*-solaris2*
4980 This is a synonym for @samp{sparc64-*-solaris2*}.
4987 The C6X family of processors. This port requires binutils-2.22 or newer.
4992 @anchor{tilegx-*-linux}
4993 @heading tilegx-*-linux*
4994 The TILE-Gx processor in little endian mode, running GNU/Linux. This
4995 port requires binutils-2.22 or newer.
5000 @anchor{tilegxbe-*-linux}
5001 @heading tilegxbe-*-linux*
5002 The TILE-Gx processor in big endian mode, running GNU/Linux. This
5003 port requires binutils-2.23 or newer.
5008 @anchor{tilepro-*-linux}
5009 @heading tilepro-*-linux*
5010 The TILEPro processor running GNU/Linux. This port requires
5011 binutils-2.22 or newer.
5016 @anchor{visium-x-elf}
5017 @heading visium-*-elf
5018 CDS VISIUMcore processor.
5019 This configuration is intended for embedded systems.
5024 @anchor{x-x-vxworks}
5025 @heading *-*-vxworks*
5026 Support for VxWorks is in flux. At present GCC supports @emph{only} the
5027 very recent VxWorks 5.5 (aka Tornado 2.2) release, and only on PowerPC@.
5028 We welcome patches for other architectures supported by VxWorks 5.5.
5029 Support for VxWorks AE would also be welcome; we believe this is merely
5030 a matter of writing an appropriate ``configlette'' (see below). We are
5031 not interested in supporting older, a.out or COFF-based, versions of
5034 VxWorks comes with an older version of GCC installed in
5035 @file{@var{$WIND_BASE}/host}; we recommend you do not overwrite it.
5036 Choose an installation @var{prefix} entirely outside @var{$WIND_BASE}.
5037 Before running @command{configure}, create the directories @file{@var{prefix}}
5038 and @file{@var{prefix}/bin}. Link or copy the appropriate assembler,
5039 linker, etc.@: into @file{@var{prefix}/bin}, and set your @var{PATH} to
5040 include that directory while running both @command{configure} and
5043 You must give @command{configure} the
5044 @option{--with-headers=@var{$WIND_BASE}/target/h} switch so that it can
5045 find the VxWorks system headers. Since VxWorks is a cross compilation
5046 target only, you must also specify @option{--target=@var{target}}.
5047 @command{configure} will attempt to create the directory
5048 @file{@var{prefix}/@var{target}/sys-include} and copy files into it;
5049 make sure the user running @command{configure} has sufficient privilege
5052 GCC's exception handling runtime requires a special ``configlette''
5053 module, @file{contrib/gthr_supp_vxw_5x.c}. Follow the instructions in
5054 that file to add the module to your kernel build. (Future versions of
5055 VxWorks will incorporate this module.)
5061 @heading x86_64-*-*, amd64-*-*
5062 GCC supports the x86-64 architecture implemented by the AMD64 processor
5063 (amd64-*-* is an alias for x86_64-*-*) on GNU/Linux, FreeBSD and NetBSD@.
5064 On GNU/Linux the default is a bi-arch compiler which is able to generate
5065 both 64-bit x86-64 and 32-bit x86 code (via the @option{-m32} switch).
5070 @anchor{x86-64-x-solaris2}
5071 @heading x86_64-*-solaris2*
5072 GCC also supports the x86-64 architecture implemented by the AMD64
5073 processor (@samp{amd64-*-*} is an alias for @samp{x86_64-*-*}) on
5074 Solaris 10 or later. Unlike other systems, without special options a
5075 bi-arch compiler is built which generates 32-bit code by default, but
5076 can generate 64-bit x86-64 code with the @option{-m64} switch. Since
5077 GCC 4.7, there is also a configuration that defaults to 64-bit code, but
5078 can generate 32-bit code with @option{-m32}. To configure and build
5079 this way, you have to provide all support libraries like @file{libgmp}
5080 as 64-bit code, configure with @option{--target=x86_64-pc-solaris2.11}
5081 and @samp{CC=gcc -m64}.
5086 @anchor{xtensa-x-elf}
5087 @heading xtensa*-*-elf
5088 This target is intended for embedded Xtensa systems using the
5089 @samp{newlib} C library. It uses ELF but does not support shared
5090 objects. Designed-defined instructions specified via the
5091 Tensilica Instruction Extension (TIE) language are only supported
5092 through inline assembly.
5094 The Xtensa configuration information must be specified prior to
5095 building GCC@. The @file{include/xtensa-config.h} header
5096 file contains the configuration information. If you created your
5097 own Xtensa configuration with the Xtensa Processor Generator, the
5098 downloaded files include a customized copy of this header file,
5099 which you can use to replace the default header file.
5104 @anchor{xtensa-x-linux}
5105 @heading xtensa*-*-linux*
5106 This target is for Xtensa systems running GNU/Linux. It supports ELF
5107 shared objects and the GNU C library (glibc). It also generates
5108 position-independent code (PIC) regardless of whether the
5109 @option{-fpic} or @option{-fPIC} options are used. In other
5110 respects, this target is the same as the
5111 @uref{#xtensa*-*-elf,,@samp{xtensa*-*-elf}} target.
5117 @heading Microsoft Windows
5119 @subheading Intel 16-bit versions
5120 The 16-bit versions of Microsoft Windows, such as Windows 3.1, are not
5123 However, the 32-bit port has limited support for Microsoft
5124 Windows 3.11 in the Win32s environment, as a target only. See below.
5126 @subheading Intel 32-bit versions
5127 The 32-bit versions of Windows, including Windows 95, Windows NT, Windows
5128 XP, and Windows Vista, are supported by several different target
5129 platforms. These targets differ in which Windows subsystem they target
5130 and which C libraries are used.
5133 @item Cygwin @uref{#x-x-cygwin,,*-*-cygwin}: Cygwin provides a user-space
5134 Linux API emulation layer in the Win32 subsystem.
5135 @item MinGW @uref{#x-x-mingw32,,*-*-mingw32}: MinGW is a native GCC port for
5136 the Win32 subsystem that provides a subset of POSIX.
5137 @item MKS i386-pc-mks: NuTCracker from MKS. See
5138 @uref{https://www.mkssoftware.com} for more information.
5141 @subheading Intel 64-bit versions
5142 GCC contains support for x86-64 using the mingw-w64
5143 runtime library, available from @uref{https://www.mingw-w64.org/downloads/}.
5144 This library should be used with the target triple x86_64-pc-mingw32.
5146 @subheading Windows CE
5147 Windows CE is supported as a target only on Hitachi
5148 SuperH (sh-wince-pe), and MIPS (mips-wince-pe).
5150 @subheading Other Windows Platforms
5151 GCC no longer supports Windows NT on the Alpha or PowerPC.
5153 GCC no longer supports the Windows POSIX subsystem. However, it does
5154 support the Interix subsystem. See above.
5156 Old target names including *-*-winnt and *-*-windowsnt are no longer used.
5158 PW32 (i386-pc-pw32) support was never completed, and the project seems to
5159 be inactive. See @uref{http://pw32.sourceforge.net/} for more information.
5161 UWIN support has been removed due to a lack of maintenance.
5168 Ports of GCC are included with the
5169 @uref{http://www.cygwin.com/,,Cygwin environment}.
5171 GCC will build under Cygwin without modification; it does not build
5172 with Microsoft's C++ compiler and there are no plans to make it do so.
5174 The Cygwin native compiler can be configured to target any 32-bit x86
5175 cpu architecture desired; the default is i686-pc-cygwin. It should be
5176 used with as up-to-date a version of binutils as possible; use either
5177 the latest official GNU binutils release in the Cygwin distribution,
5178 or version 2.20 or above if building your own.
5183 @anchor{x-x-mingw32}
5184 @heading *-*-mingw32
5185 GCC will build with and support only MinGW runtime 3.12 and later.
5186 Earlier versions of headers are incompatible with the new default semantics
5187 of @code{extern inline} in @code{-std=c99} and @code{-std=gnu99} modes.
5189 To support emitting DWARF debugging info you need to use GNU binutils
5190 version 2.16 or above containing support for the @code{.secrel32}
5191 assembler pseudo-op.
5197 @heading Older systems
5198 GCC contains support files for many older (1980s and early
5199 1990s) Unix variants. For the most part, support for these systems
5200 has not been deliberately removed, but it has not been maintained for
5201 several years and may suffer from bitrot.
5203 Starting with GCC 3.1, each release has a list of ``obsoleted'' systems.
5204 Support for these systems is still present in that release, but
5205 @command{configure} will fail unless the @option{--enable-obsolete}
5206 option is given. Unless a maintainer steps forward, support for these
5207 systems will be removed from the next release of GCC@.
5209 Support for old systems as hosts for GCC can cause problems if the
5210 workarounds for compiler, library and operating system bugs affect the
5211 cleanliness or maintainability of the rest of GCC@. In some cases, to
5212 bring GCC up on such a system, if still possible with current GCC, may
5213 require first installing an old version of GCC which did work on that
5214 system, and using it to compile a more recent GCC, to avoid bugs in the
5215 vendor compiler. Old releases of GCC 1 and GCC 2 are available in the
5216 @file{old-releases} directory on the @uref{../mirrors.html,,GCC mirror
5217 sites}. Header bugs may generally be avoided using
5218 @command{fixincludes}, but bugs or deficiencies in libraries and the
5219 operating system may still cause problems.
5221 Support for older systems as targets for cross-compilation is less
5222 problematic than support for them as hosts for GCC; if an enthusiast
5223 wishes to make such a target work again (including resurrecting any of
5224 the targets that never worked with GCC 2, starting from the last
5225 version before they were removed), patches
5226 @uref{../contribute.html,,following the usual requirements} would be
5227 likely to be accepted, since they should not affect the support for more
5230 For some systems, old versions of GNU binutils may also be useful,
5231 and are available from @file{pub/binutils/old-releases} on
5232 @uref{https://sourceware.org/mirrors.html,,sourceware.org mirror sites}.
5234 Some of the information on specific systems above relates to
5235 such older systems, but much of the information
5236 about GCC on such systems (which may no longer be applicable to
5237 current GCC) is to be found in the GCC texinfo manual.
5243 @heading all ELF targets (SVR4, Solaris 2, etc.)
5244 C++ support is significantly better on ELF targets if you use the
5245 @uref{./configure.html#with-gnu-ld,,GNU linker}; duplicate copies of
5246 inlines, vtables and template instantiations will be discarded
5255 @uref{./index.html,,Return to the GCC Installation page}
5259 @c ***GFDL********************************************************************
5267 @uref{./index.html,,Return to the GCC Installation page}
5271 @c ***************************************************************************
5272 @c Part 6 The End of the Document
5274 @comment node-name, next, previous, up
5275 @node Concept Index, , GNU Free Documentation License, Top
5279 @unnumbered Concept Index