install.texi: Suggest using LD_LIBRARY_PATH to find libs for GMP, MPFR and MPC.
[gcc.git] / gcc / doc / install.texi
1 \input texinfo.tex @c -*-texinfo-*-
2 @c @ifnothtml
3 @c %**start of header
4 @setfilename gccinstall.info
5 @settitle Installing GCC
6 @setchapternewpage odd
7 @c %**end of header
8 @c @end ifnothtml
9
10 @include gcc-common.texi
11
12 @c Specify title for specific html page
13 @ifset indexhtml
14 @settitle Installing GCC
15 @end ifset
16 @ifset specifichtml
17 @settitle Host/Target specific installation notes for GCC
18 @end ifset
19 @ifset prerequisiteshtml
20 @settitle Prerequisites for GCC
21 @end ifset
22 @ifset downloadhtml
23 @settitle Downloading GCC
24 @end ifset
25 @ifset configurehtml
26 @settitle Installing GCC: Configuration
27 @end ifset
28 @ifset buildhtml
29 @settitle Installing GCC: Building
30 @end ifset
31 @ifset testhtml
32 @settitle Installing GCC: Testing
33 @end ifset
34 @ifset finalinstallhtml
35 @settitle Installing GCC: Final installation
36 @end ifset
37 @ifset binarieshtml
38 @settitle Installing GCC: Binaries
39 @end ifset
40 @ifset oldhtml
41 @settitle Installing GCC: Old documentation
42 @end ifset
43 @ifset gfdlhtml
44 @settitle Installing GCC: GNU Free Documentation License
45 @end ifset
46
47 @c Copyright (C) 1988, 1989, 1992, 1993, 1994, 1995, 1996, 1997, 1998,
48 @c 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009,
49 @c 2010 Free Software Foundation, Inc.
50 @c *** Converted to texinfo by Dean Wakerley, dean@wakerley.com
51
52 @c IMPORTANT: whenever you modify this file, run `install.texi2html' to
53 @c test the generation of HTML documents for the gcc.gnu.org web pages.
54 @c
55 @c Do not use @footnote{} in this file as it breaks install.texi2html!
56
57 @c Include everything if we're not making html
58 @ifnothtml
59 @set indexhtml
60 @set specifichtml
61 @set prerequisiteshtml
62 @set downloadhtml
63 @set configurehtml
64 @set buildhtml
65 @set testhtml
66 @set finalinstallhtml
67 @set binarieshtml
68 @set oldhtml
69 @set gfdlhtml
70 @end ifnothtml
71
72 @c Part 2 Summary Description and Copyright
73 @copying
74 Copyright @copyright{} 1988, 1989, 1992, 1993, 1994, 1995, 1996, 1997,
75 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009,
76 2010 Free Software Foundation, Inc.
77 @sp 1
78 Permission is granted to copy, distribute and/or modify this document
79 under the terms of the GNU Free Documentation License, Version 1.3 or
80 any later version published by the Free Software Foundation; with no
81 Invariant Sections, the Front-Cover texts being (a) (see below), and
82 with the Back-Cover Texts being (b) (see below). A copy of the
83 license is included in the section entitled ``@uref{./gfdl.html,,GNU
84 Free Documentation License}''.
85
86 (a) The FSF's Front-Cover Text is:
87
88 A GNU Manual
89
90 (b) The FSF's Back-Cover Text is:
91
92 You have freedom to copy and modify this GNU Manual, like GNU
93 software. Copies published by the Free Software Foundation raise
94 funds for GNU development.
95 @end copying
96 @ifinfo
97 @insertcopying
98 @end ifinfo
99 @dircategory Software development
100 @direntry
101 * gccinstall: (gccinstall). Installing the GNU Compiler Collection.
102 @end direntry
103
104 @c Part 3 Titlepage and Copyright
105 @titlepage
106 @title Installing GCC
107 @versionsubtitle
108
109 @c The following two commands start the copyright page.
110 @page
111 @vskip 0pt plus 1filll
112 @insertcopying
113 @end titlepage
114
115 @c Part 4 Top node, Master Menu, and/or Table of Contents
116 @ifinfo
117 @node Top, , , (dir)
118 @comment node-name, next, Previous, up
119
120 @menu
121 * Installing GCC:: This document describes the generic installation
122 procedure for GCC as well as detailing some target
123 specific installation instructions.
124
125 * Specific:: Host/target specific installation notes for GCC.
126 * Binaries:: Where to get pre-compiled binaries.
127
128 * Old:: Old installation documentation.
129
130 * GNU Free Documentation License:: How you can copy and share this manual.
131 * Concept Index:: This index has two entries.
132 @end menu
133 @end ifinfo
134
135 @iftex
136 @contents
137 @end iftex
138
139 @c Part 5 The Body of the Document
140 @c ***Installing GCC**********************************************************
141 @ifnothtml
142 @comment node-name, next, previous, up
143 @node Installing GCC, Binaries, , Top
144 @end ifnothtml
145 @ifset indexhtml
146 @ifnothtml
147 @chapter Installing GCC
148 @end ifnothtml
149
150 The latest version of this document is always available at
151 @uref{http://gcc.gnu.org/install/,,http://gcc.gnu.org/install/}.
152
153 This document describes the generic installation procedure for GCC as well
154 as detailing some target specific installation instructions.
155
156 GCC includes several components that previously were separate distributions
157 with their own installation instructions. This document supersedes all
158 package specific installation instructions.
159
160 @emph{Before} starting the build/install procedure please check the
161 @ifnothtml
162 @ref{Specific, host/target specific installation notes}.
163 @end ifnothtml
164 @ifhtml
165 @uref{specific.html,,host/target specific installation notes}.
166 @end ifhtml
167 We recommend you browse the entire generic installation instructions before
168 you proceed.
169
170 Lists of successful builds for released versions of GCC are
171 available at @uref{http://gcc.gnu.org/buildstat.html}.
172 These lists are updated as new information becomes available.
173
174 The installation procedure itself is broken into five steps.
175
176 @ifinfo
177 @menu
178 * Prerequisites::
179 * Downloading the source::
180 * Configuration::
181 * Building::
182 * Testing:: (optional)
183 * Final install::
184 @end menu
185 @end ifinfo
186 @ifhtml
187 @enumerate
188 @item
189 @uref{prerequisites.html,,Prerequisites}
190 @item
191 @uref{download.html,,Downloading the source}
192 @item
193 @uref{configure.html,,Configuration}
194 @item
195 @uref{build.html,,Building}
196 @item
197 @uref{test.html,,Testing} (optional)
198 @item
199 @uref{finalinstall.html,,Final install}
200 @end enumerate
201 @end ifhtml
202
203 Please note that GCC does not support @samp{make uninstall} and probably
204 won't do so in the near future as this would open a can of worms. Instead,
205 we suggest that you install GCC into a directory of its own and simply
206 remove that directory when you do not need that specific version of GCC
207 any longer, and, if shared libraries are installed there as well, no
208 more binaries exist that use them.
209
210 @ifhtml
211 There are also some @uref{old.html,,old installation instructions},
212 which are mostly obsolete but still contain some information which has
213 not yet been merged into the main part of this manual.
214 @end ifhtml
215
216 @html
217 <hr />
218 <p>
219 @end html
220 @ifhtml
221 @uref{./index.html,,Return to the GCC Installation page}
222
223 @insertcopying
224 @end ifhtml
225 @end ifset
226
227 @c ***Prerequisites**************************************************
228 @ifnothtml
229 @comment node-name, next, previous, up
230 @node Prerequisites, Downloading the source, , Installing GCC
231 @end ifnothtml
232 @ifset prerequisiteshtml
233 @ifnothtml
234 @chapter Prerequisites
235 @end ifnothtml
236 @cindex Prerequisites
237
238 GCC requires that various tools and packages be available for use in the
239 build procedure. Modifying GCC sources requires additional tools
240 described below.
241
242 @heading Tools/packages necessary for building GCC
243 @table @asis
244 @item ISO C90 compiler
245 Necessary to bootstrap GCC, although versions of GCC prior
246 to 3.4 also allow bootstrapping with a traditional (K&R) C compiler.
247
248 To build all languages in a cross-compiler or other configuration where
249 3-stage bootstrap is not performed, you need to start with an existing
250 GCC binary (version 2.95 or later) because source code for language
251 frontends other than C might use GCC extensions.
252
253 @item GNAT
254
255 In order to build the Ada compiler (GNAT) you must already have GNAT
256 installed because portions of the Ada frontend are written in Ada (with
257 GNAT extensions.) Refer to the Ada installation instructions for more
258 specific information.
259
260 @item A ``working'' POSIX compatible shell, or GNU bash
261
262 Necessary when running @command{configure} because some
263 @command{/bin/sh} shells have bugs and may crash when configuring the
264 target libraries. In other cases, @command{/bin/sh} or @command{ksh}
265 have disastrous corner-case performance problems. This
266 can cause target @command{configure} runs to literally take days to
267 complete in some cases.
268
269 So on some platforms @command{/bin/ksh} is sufficient, on others it
270 isn't. See the host/target specific instructions for your platform, or
271 use @command{bash} to be sure. Then set @env{CONFIG_SHELL} in your
272 environment to your ``good'' shell prior to running
273 @command{configure}/@command{make}.
274
275 @command{zsh} is not a fully compliant POSIX shell and will not
276 work when configuring GCC@.
277
278 @item A POSIX or SVR4 awk
279
280 Necessary for creating some of the generated source files for GCC@.
281 If in doubt, use a recent GNU awk version, as some of the older ones
282 are broken. GNU awk version 3.1.5 is known to work.
283
284 @item GNU binutils
285
286 Necessary in some circumstances, optional in others. See the
287 host/target specific instructions for your platform for the exact
288 requirements.
289
290 @item gzip version 1.2.4 (or later) or
291 @itemx bzip2 version 1.0.2 (or later)
292
293 Necessary to uncompress GCC @command{tar} files when source code is
294 obtained via FTP mirror sites.
295
296 @item GNU make version 3.80 (or later)
297
298 You must have GNU make installed to build GCC@.
299
300 @item GNU tar version 1.14 (or later)
301
302 Necessary (only on some platforms) to untar the source code. Many
303 systems' @command{tar} programs will also work, only try GNU
304 @command{tar} if you have problems.
305
306 @item GNU Multiple Precision Library (GMP) version 4.3.2 (or later)
307
308 Necessary to build GCC@. If you do not have it installed in your
309 library search path, you will have to configure with the
310 @option{--with-gmp} configure option. See also @option{--with-gmp-lib}
311 and @option{--with-gmp-include}. Alternatively, if a GMP source
312 distribution is found in a subdirectory of your GCC sources named
313 @file{gmp}, it will be built together with GCC@.
314
315 @item MPFR Library version 2.4.2 (or later)
316
317 Necessary to build GCC@. It can be downloaded from
318 @uref{http://www.mpfr.org/}. The @option{--with-mpfr} configure
319 option should be used if your MPFR Library is not installed in your
320 default library search path. See also @option{--with-mpfr-lib} and
321 @option{--with-mpfr-include}. Alternatively, if a MPFR source
322 distribution is found in a subdirectory of your GCC sources named
323 @file{mpfr}, it will be built together with GCC@.
324
325 @item MPC Library version 0.8.1 (or later)
326
327 Necessary to build GCC@. It can be downloaded from
328 @uref{http://www.multiprecision.org/}. The @option{--with-mpc}
329 configure option should be used if your MPC Library is not installed
330 in your default library search path. See also @option{--with-mpc-lib}
331 and @option{--with-mpc-include}. Alternatively, if an MPC source
332 distribution is found in a subdirectory of your GCC sources named
333 @file{mpc}, it will be built together with GCC@.
334
335 @item Parma Polyhedra Library (PPL) version 0.10
336
337 Necessary to build GCC with the Graphite loop optimizations.
338 It can be downloaded from @uref{http://www.cs.unipr.it/ppl/Download/}.
339
340 The @option{--with-ppl} configure option should be used if PPL is not
341 installed in your default library search path.
342
343 @item CLooG-PPL version 0.15
344
345 Necessary to build GCC with the Graphite loop optimizations. It can
346 be downloaded from @uref{ftp://gcc.gnu.org/pub/gcc/infrastructure/}.
347 The code in @file{cloog-ppl-0.15.tar.gz} comes from a branch of CLooG
348 available from @uref{http://repo.or.cz/w/cloog-ppl.git}. CLooG-PPL
349 should be configured with @option{--with-ppl}.
350
351 The @option{--with-cloog} configure option should be used if CLooG is
352 not installed in your default library search path.
353
354 @item @command{jar}, or InfoZIP (@command{zip} and @command{unzip})
355
356 Necessary to build libgcj, the GCJ runtime.
357
358 @item libelf version 0.8.12 (or later)
359
360 Necessary to build link-time optimization (LTO) support. It can be
361 downloaded from @uref{http://www.mr511.de/software/libelf-0.8.12.tar.gz},
362 though it is commonly available in several systems. The version in
363 IRIX 6.5 doesn't work since it lacks @file{gelf.h}. The version in
364 Solaris 2 does work.
365
366 The @option{--with-libelf} configure option should be used if libelf is
367 not installed in your default library search patch.
368
369 @end table
370
371 @heading Tools/packages necessary for modifying GCC
372 @table @asis
373 @item autoconf version 2.64
374 @itemx GNU m4 version 1.4.6 (or later)
375
376 Necessary when modifying @file{configure.ac}, @file{aclocal.m4}, etc.@:
377 to regenerate @file{configure} and @file{config.in} files.
378
379 @item automake version 1.11.1
380
381 Necessary when modifying a @file{Makefile.am} file to regenerate its
382 associated @file{Makefile.in}.
383
384 Much of GCC does not use automake, so directly edit the @file{Makefile.in}
385 file. Specifically this applies to the @file{gcc}, @file{intl},
386 @file{libcpp}, @file{libiberty}, @file{libobjc} directories as well
387 as any of their subdirectories.
388
389 For directories that use automake, GCC requires the latest release in
390 the 1.11 series, which is currently 1.11.1. When regenerating a directory
391 to a newer version, please update all the directories using an older 1.11
392 to the latest released version.
393
394 @item gettext version 0.14.5 (or later)
395
396 Needed to regenerate @file{gcc.pot}.
397
398 @item gperf version 2.7.2 (or later)
399
400 Necessary when modifying @command{gperf} input files, e.g.@:
401 @file{gcc/cp/cfns.gperf} to regenerate its associated header file, e.g.@:
402 @file{gcc/cp/cfns.h}.
403
404 @item DejaGnu 1.4.4
405 @itemx Expect
406 @itemx Tcl
407
408 Necessary to run the GCC testsuite; see the section on testing for details.
409
410 @item autogen version 5.5.4 (or later) and
411 @itemx guile version 1.4.1 (or later)
412
413 Necessary to regenerate @file{fixinc/fixincl.x} from
414 @file{fixinc/inclhack.def} and @file{fixinc/*.tpl}.
415
416 Necessary to run @samp{make check} for @file{fixinc}.
417
418 Necessary to regenerate the top level @file{Makefile.in} file from
419 @file{Makefile.tpl} and @file{Makefile.def}.
420
421 @item Flex version 2.5.4 (or later)
422
423 Necessary when modifying @file{*.l} files.
424
425 Necessary to build GCC during development because the generated output
426 files are not included in the SVN repository. They are included in
427 releases.
428
429 @item Texinfo version 4.7 (or later)
430
431 Necessary for running @command{makeinfo} when modifying @file{*.texi}
432 files to test your changes.
433
434 Necessary for running @command{make dvi} or @command{make pdf} to
435 create printable documentation in DVI or PDF format. Texinfo version
436 4.8 or later is required for @command{make pdf}.
437
438 Necessary to build GCC documentation during development because the
439 generated output files are not included in the SVN repository. They are
440 included in releases.
441
442 @item @TeX{} (any working version)
443
444 Necessary for running @command{texi2dvi} and @command{texi2pdf}, which
445 are used when running @command{make dvi} or @command{make pdf} to create
446 DVI or PDF files, respectively.
447
448 @item SVN (any version)
449 @itemx SSH (any version)
450
451 Necessary to access the SVN repository. Public releases and weekly
452 snapshots of the development sources are also available via FTP@.
453
454 @item Perl version 5.6.1 (or later)
455
456 Necessary when regenerating @file{Makefile} dependencies in libiberty.
457 Necessary when regenerating @file{libiberty/functions.texi}.
458 Necessary when generating manpages from Texinfo manuals.
459 Necessary when targetting Darwin, building @samp{libstdc++},
460 and not using @option{--disable-symvers}.
461 Necessary when targetting Solaris 2 with Sun @command{ld}, building
462 @samp{libstdc++}, and not using @option{--disable-symvers}. A helper
463 scripts needs @samp{Glob.pm}, which is missing from @command{perl} 5.005
464 included in Solaris~8. The bundled @command{perl} in Solaris~9 and up
465 works.
466 Used by various scripts to generate some files included in SVN (mainly
467 Unicode-related and rarely changing) from source tables.
468
469 @item GNU diffutils version 2.7 (or later)
470
471 Useful when submitting patches for the GCC source code.
472
473 @item patch version 2.5.4 (or later)
474
475 Necessary when applying patches, created with @command{diff}, to one's
476 own sources.
477
478 @item ecj1
479 @itemx gjavah
480
481 If you wish to modify @file{.java} files in libjava, you will need to
482 configure with @option{--enable-java-maintainer-mode}, and you will need
483 to have executables named @command{ecj1} and @command{gjavah} in your path.
484 The @command{ecj1} executable should run the Eclipse Java compiler via
485 the GCC-specific entry point. You can download a suitable jar from
486 @uref{ftp://sourceware.org/pub/java/}, or by running the script
487 @command{contrib/download_ecj}.
488
489 @item antlr.jar version 2.7.1 (or later)
490 @itemx antlr binary
491
492 If you wish to build the @command{gjdoc} binary in libjava, you will
493 need to have an @file{antlr.jar} library available. The library is
494 searched in system locations but can be configured with
495 @option{--with-antlr-jar=} instead. When configuring with
496 @option{--enable-java-maintainer-mode}, you will need to have one of
497 the executables named @command{cantlr}, @command{runantlr} or
498 @command{antlr} in your path.
499
500 @end table
501
502 @html
503 <hr />
504 <p>
505 @end html
506 @ifhtml
507 @uref{./index.html,,Return to the GCC Installation page}
508 @end ifhtml
509 @end ifset
510
511 @c ***Downloading the source**************************************************
512 @ifnothtml
513 @comment node-name, next, previous, up
514 @node Downloading the source, Configuration, Prerequisites, Installing GCC
515 @end ifnothtml
516 @ifset downloadhtml
517 @ifnothtml
518 @chapter Downloading GCC
519 @end ifnothtml
520 @cindex Downloading GCC
521 @cindex Downloading the Source
522
523 GCC is distributed via @uref{http://gcc.gnu.org/svn.html,,SVN} and FTP
524 tarballs compressed with @command{gzip} or
525 @command{bzip2}. It is possible to download a full distribution or specific
526 components.
527
528 Please refer to the @uref{http://gcc.gnu.org/releases.html,,releases web page}
529 for information on how to obtain GCC@.
530
531 The full distribution includes the C, C++, Objective-C, Fortran, Java,
532 and Ada (in the case of GCC 3.1 and later) compilers. The full
533 distribution also includes runtime libraries for C++, Objective-C,
534 Fortran, and Java. In GCC 3.0 and later versions, the GNU compiler
535 testsuites are also included in the full distribution.
536
537 If you choose to download specific components, you must download the core
538 GCC distribution plus any language specific distributions you wish to
539 use. The core distribution includes the C language front end as well as the
540 shared components. Each language has a tarball which includes the language
541 front end as well as the language runtime (when appropriate).
542
543 Unpack the core distribution as well as any language specific
544 distributions in the same directory.
545
546 If you also intend to build binutils (either to upgrade an existing
547 installation or for use in place of the corresponding tools of your
548 OS), unpack the binutils distribution either in the same directory or
549 a separate one. In the latter case, add symbolic links to any
550 components of the binutils you intend to build alongside the compiler
551 (@file{bfd}, @file{binutils}, @file{gas}, @file{gprof}, @file{ld},
552 @file{opcodes}, @dots{}) to the directory containing the GCC sources.
553
554 Likewise the GMP, MPFR and MPC libraries can be automatically built
555 together with GCC. Unpack the GMP, MPFR and/or MPC source
556 distributions in the directory containing the GCC sources and rename
557 their directories to @file{gmp}, @file{mpfr} and @file{mpc},
558 respectively (or use symbolic links with the same name).
559
560 @html
561 <hr />
562 <p>
563 @end html
564 @ifhtml
565 @uref{./index.html,,Return to the GCC Installation page}
566 @end ifhtml
567 @end ifset
568
569 @c ***Configuration***********************************************************
570 @ifnothtml
571 @comment node-name, next, previous, up
572 @node Configuration, Building, Downloading the source, Installing GCC
573 @end ifnothtml
574 @ifset configurehtml
575 @ifnothtml
576 @chapter Installing GCC: Configuration
577 @end ifnothtml
578 @cindex Configuration
579 @cindex Installing GCC: Configuration
580
581 Like most GNU software, GCC must be configured before it can be built.
582 This document describes the recommended configuration procedure
583 for both native and cross targets.
584
585 We use @var{srcdir} to refer to the toplevel source directory for
586 GCC; we use @var{objdir} to refer to the toplevel build/object directory.
587
588 If you obtained the sources via SVN, @var{srcdir} must refer to the top
589 @file{gcc} directory, the one where the @file{MAINTAINERS} file can be
590 found, and not its @file{gcc} subdirectory, otherwise the build will fail.
591
592 If either @var{srcdir} or @var{objdir} is located on an automounted NFS
593 file system, the shell's built-in @command{pwd} command will return
594 temporary pathnames. Using these can lead to various sorts of build
595 problems. To avoid this issue, set the @env{PWDCMD} environment
596 variable to an automounter-aware @command{pwd} command, e.g.,
597 @command{pawd} or @samp{amq -w}, during the configuration and build
598 phases.
599
600 First, we @strong{highly} recommend that GCC be built into a
601 separate directory from the sources which does @strong{not} reside
602 within the source tree. This is how we generally build GCC; building
603 where @var{srcdir} == @var{objdir} should still work, but doesn't
604 get extensive testing; building where @var{objdir} is a subdirectory
605 of @var{srcdir} is unsupported.
606
607 If you have previously built GCC in the same directory for a
608 different target machine, do @samp{make distclean} to delete all files
609 that might be invalid. One of the files this deletes is @file{Makefile};
610 if @samp{make distclean} complains that @file{Makefile} does not exist
611 or issues a message like ``don't know how to make distclean'' it probably
612 means that the directory is already suitably clean. However, with the
613 recommended method of building in a separate @var{objdir}, you should
614 simply use a different @var{objdir} for each target.
615
616 Second, when configuring a native system, either @command{cc} or
617 @command{gcc} must be in your path or you must set @env{CC} in
618 your environment before running configure. Otherwise the configuration
619 scripts may fail.
620
621 @ignore
622 Note that the bootstrap compiler and the resulting GCC must be link
623 compatible, else the bootstrap will fail with linker errors about
624 incompatible object file formats. Several multilibed targets are
625 affected by this requirement, see
626 @ifnothtml
627 @ref{Specific, host/target specific installation notes}.
628 @end ifnothtml
629 @ifhtml
630 @uref{specific.html,,host/target specific installation notes}.
631 @end ifhtml
632 @end ignore
633
634 To configure GCC:
635
636 @smallexample
637 % mkdir @var{objdir}
638 % cd @var{objdir}
639 % @var{srcdir}/configure [@var{options}] [@var{target}]
640 @end smallexample
641
642 @heading Distributor options
643
644 If you will be distributing binary versions of GCC, with modifications
645 to the source code, you should use the options described in this
646 section to make clear that your version contains modifications.
647
648 @table @code
649 @item --with-pkgversion=@var{version}
650 Specify a string that identifies your package. You may wish
651 to include a build number or build date. This version string will be
652 included in the output of @command{gcc --version}. This suffix does
653 not replace the default version string, only the @samp{GCC} part.
654
655 The default value is @samp{GCC}.
656
657 @item --with-bugurl=@var{url}
658 Specify the URL that users should visit if they wish to report a bug.
659 You are of course welcome to forward bugs reported to you to the FSF,
660 if you determine that they are not bugs in your modifications.
661
662 The default value refers to the FSF's GCC bug tracker.
663
664 @end table
665
666 @heading Target specification
667 @itemize @bullet
668 @item
669 GCC has code to correctly determine the correct value for @var{target}
670 for nearly all native systems. Therefore, we highly recommend you do
671 not provide a configure target when configuring a native compiler.
672
673 @item
674 @var{target} must be specified as @option{--target=@var{target}}
675 when configuring a cross compiler; examples of valid targets would be
676 m68k-elf, sh-elf, etc.
677
678 @item
679 Specifying just @var{target} instead of @option{--target=@var{target}}
680 implies that the host defaults to @var{target}.
681 @end itemize
682
683
684 @heading Options specification
685
686 Use @var{options} to override several configure time options for
687 GCC@. A list of supported @var{options} follows; @samp{configure
688 --help} may list other options, but those not listed below may not
689 work and should not normally be used.
690
691 Note that each @option{--enable} option has a corresponding
692 @option{--disable} option and that each @option{--with} option has a
693 corresponding @option{--without} option.
694
695 @table @code
696 @item --prefix=@var{dirname}
697 Specify the toplevel installation
698 directory. This is the recommended way to install the tools into a directory
699 other than the default. The toplevel installation directory defaults to
700 @file{/usr/local}.
701
702 We @strong{highly} recommend against @var{dirname} being the same or a
703 subdirectory of @var{objdir} or vice versa. If specifying a directory
704 beneath a user's home directory tree, some shells will not expand
705 @var{dirname} correctly if it contains the @samp{~} metacharacter; use
706 @env{$HOME} instead.
707
708 The following standard @command{autoconf} options are supported. Normally you
709 should not need to use these options.
710 @table @code
711 @item --exec-prefix=@var{dirname}
712 Specify the toplevel installation directory for architecture-dependent
713 files. The default is @file{@var{prefix}}.
714
715 @item --bindir=@var{dirname}
716 Specify the installation directory for the executables called by users
717 (such as @command{gcc} and @command{g++}). The default is
718 @file{@var{exec-prefix}/bin}.
719
720 @item --libdir=@var{dirname}
721 Specify the installation directory for object code libraries and
722 internal data files of GCC@. The default is @file{@var{exec-prefix}/lib}.
723
724 @item --libexecdir=@var{dirname}
725 Specify the installation directory for internal executables of GCC@.
726 The default is @file{@var{exec-prefix}/libexec}.
727
728 @item --with-slibdir=@var{dirname}
729 Specify the installation directory for the shared libgcc library. The
730 default is @file{@var{libdir}}.
731
732 @item --datarootdir=@var{dirname}
733 Specify the root of the directory tree for read-only architecture-independent
734 data files referenced by GCC@. The default is @file{@var{prefix}/share}.
735
736 @item --infodir=@var{dirname}
737 Specify the installation directory for documentation in info format.
738 The default is @file{@var{datarootdir}/info}.
739
740 @item --datadir=@var{dirname}
741 Specify the installation directory for some architecture-independent
742 data files referenced by GCC@. The default is @file{@var{datarootdir}}.
743
744 @item --docdir=@var{dirname}
745 Specify the installation directory for documentation files (other
746 than Info) for GCC@. The default is @file{@var{datarootdir}/doc}.
747
748 @item --htmldir=@var{dirname}
749 Specify the installation directory for HTML documentation files.
750 The default is @file{@var{docdir}}.
751
752 @item --pdfdir=@var{dirname}
753 Specify the installation directory for PDF documentation files.
754 The default is @file{@var{docdir}}.
755
756 @item --mandir=@var{dirname}
757 Specify the installation directory for manual pages. The default is
758 @file{@var{datarootdir}/man}. (Note that the manual pages are only extracts
759 from the full GCC manuals, which are provided in Texinfo format. The manpages
760 are derived by an automatic conversion process from parts of the full
761 manual.)
762
763 @item --with-gxx-include-dir=@var{dirname}
764 Specify
765 the installation directory for G++ header files. The default depends
766 on other configuration options, and differs between cross and native
767 configurations.
768
769 @end table
770
771 @item --program-prefix=@var{prefix}
772 GCC supports some transformations of the names of its programs when
773 installing them. This option prepends @var{prefix} to the names of
774 programs to install in @var{bindir} (see above). For example, specifying
775 @option{--program-prefix=foo-} would result in @samp{gcc}
776 being installed as @file{/usr/local/bin/foo-gcc}.
777
778 @item --program-suffix=@var{suffix}
779 Appends @var{suffix} to the names of programs to install in @var{bindir}
780 (see above). For example, specifying @option{--program-suffix=-3.1}
781 would result in @samp{gcc} being installed as
782 @file{/usr/local/bin/gcc-3.1}.
783
784 @item --program-transform-name=@var{pattern}
785 Applies the @samp{sed} script @var{pattern} to be applied to the names
786 of programs to install in @var{bindir} (see above). @var{pattern} has to
787 consist of one or more basic @samp{sed} editing commands, separated by
788 semicolons. For example, if you want the @samp{gcc} program name to be
789 transformed to the installed program @file{/usr/local/bin/myowngcc} and
790 the @samp{g++} program name to be transformed to
791 @file{/usr/local/bin/gspecial++} without changing other program names,
792 you could use the pattern
793 @option{--program-transform-name='s/^gcc$/myowngcc/; s/^g++$/gspecial++/'}
794 to achieve this effect.
795
796 All three options can be combined and used together, resulting in more
797 complex conversion patterns. As a basic rule, @var{prefix} (and
798 @var{suffix}) are prepended (appended) before further transformations
799 can happen with a special transformation script @var{pattern}.
800
801 As currently implemented, this option only takes effect for native
802 builds; cross compiler binaries' names are not transformed even when a
803 transformation is explicitly asked for by one of these options.
804
805 For native builds, some of the installed programs are also installed
806 with the target alias in front of their name, as in
807 @samp{i686-pc-linux-gnu-gcc}. All of the above transformations happen
808 before the target alias is prepended to the name---so, specifying
809 @option{--program-prefix=foo-} and @option{program-suffix=-3.1}, the
810 resulting binary would be installed as
811 @file{/usr/local/bin/i686-pc-linux-gnu-foo-gcc-3.1}.
812
813 As a last shortcoming, none of the installed Ada programs are
814 transformed yet, which will be fixed in some time.
815
816 @item --with-local-prefix=@var{dirname}
817 Specify the
818 installation directory for local include files. The default is
819 @file{/usr/local}. Specify this option if you want the compiler to
820 search directory @file{@var{dirname}/include} for locally installed
821 header files @emph{instead} of @file{/usr/local/include}.
822
823 You should specify @option{--with-local-prefix} @strong{only} if your
824 site has a different convention (not @file{/usr/local}) for where to put
825 site-specific files.
826
827 The default value for @option{--with-local-prefix} is @file{/usr/local}
828 regardless of the value of @option{--prefix}. Specifying
829 @option{--prefix} has no effect on which directory GCC searches for
830 local header files. This may seem counterintuitive, but actually it is
831 logical.
832
833 The purpose of @option{--prefix} is to specify where to @emph{install
834 GCC}. The local header files in @file{/usr/local/include}---if you put
835 any in that directory---are not part of GCC@. They are part of other
836 programs---perhaps many others. (GCC installs its own header files in
837 another directory which is based on the @option{--prefix} value.)
838
839 Both the local-prefix include directory and the GCC-prefix include
840 directory are part of GCC's ``system include'' directories. Although these
841 two directories are not fixed, they need to be searched in the proper
842 order for the correct processing of the include_next directive. The
843 local-prefix include directory is searched before the GCC-prefix
844 include directory. Another characteristic of system include directories
845 is that pedantic warnings are turned off for headers in these directories.
846
847 Some autoconf macros add @option{-I @var{directory}} options to the
848 compiler command line, to ensure that directories containing installed
849 packages' headers are searched. When @var{directory} is one of GCC's
850 system include directories, GCC will ignore the option so that system
851 directories continue to be processed in the correct order. This
852 may result in a search order different from what was specified but the
853 directory will still be searched.
854
855 GCC automatically searches for ordinary libraries using
856 @env{GCC_EXEC_PREFIX}. Thus, when the same installation prefix is
857 used for both GCC and packages, GCC will automatically search for
858 both headers and libraries. This provides a configuration that is
859 easy to use. GCC behaves in a manner similar to that when it is
860 installed as a system compiler in @file{/usr}.
861
862 Sites that need to install multiple versions of GCC may not want to
863 use the above simple configuration. It is possible to use the
864 @option{--program-prefix}, @option{--program-suffix} and
865 @option{--program-transform-name} options to install multiple versions
866 into a single directory, but it may be simpler to use different prefixes
867 and the @option{--with-local-prefix} option to specify the location of the
868 site-specific files for each version. It will then be necessary for
869 users to specify explicitly the location of local site libraries
870 (e.g., with @env{LIBRARY_PATH}).
871
872 The same value can be used for both @option{--with-local-prefix} and
873 @option{--prefix} provided it is not @file{/usr}. This can be used
874 to avoid the default search of @file{/usr/local/include}.
875
876 @strong{Do not} specify @file{/usr} as the @option{--with-local-prefix}!
877 The directory you use for @option{--with-local-prefix} @strong{must not}
878 contain any of the system's standard header files. If it did contain
879 them, certain programs would be miscompiled (including GNU Emacs, on
880 certain targets), because this would override and nullify the header
881 file corrections made by the @command{fixincludes} script.
882
883 Indications are that people who use this option use it based on mistaken
884 ideas of what it is for. People use it as if it specified where to
885 install part of GCC@. Perhaps they make this assumption because
886 installing GCC creates the directory.
887
888 @item --enable-shared[=@var{package}[,@dots{}]]
889 Build shared versions of libraries, if shared libraries are supported on
890 the target platform. Unlike GCC 2.95.x and earlier, shared libraries
891 are enabled by default on all platforms that support shared libraries.
892
893 If a list of packages is given as an argument, build shared libraries
894 only for the listed packages. For other packages, only static libraries
895 will be built. Package names currently recognized in the GCC tree are
896 @samp{libgcc} (also known as @samp{gcc}), @samp{libstdc++} (not
897 @samp{libstdc++-v3}), @samp{libffi}, @samp{zlib}, @samp{boehm-gc},
898 @samp{ada}, @samp{libada}, @samp{libjava} and @samp{libobjc}.
899 Note @samp{libiberty} does not support shared libraries at all.
900
901 Use @option{--disable-shared} to build only static libraries. Note that
902 @option{--disable-shared} does not accept a list of package names as
903 argument, only @option{--enable-shared} does.
904
905 @item @anchor{with-gnu-as}--with-gnu-as
906 Specify that the compiler should assume that the
907 assembler it finds is the GNU assembler. However, this does not modify
908 the rules to find an assembler and will result in confusion if the
909 assembler found is not actually the GNU assembler. (Confusion may also
910 result if the compiler finds the GNU assembler but has not been
911 configured with @option{--with-gnu-as}.) If you have more than one
912 assembler installed on your system, you may want to use this option in
913 connection with @option{--with-as=@var{pathname}} or
914 @option{--with-build-time-tools=@var{pathname}}.
915
916 The following systems are the only ones where it makes a difference
917 whether you use the GNU assembler. On any other system,
918 @option{--with-gnu-as} has no effect.
919
920 @itemize @bullet
921 @item @samp{hppa1.0-@var{any}-@var{any}}
922 @item @samp{hppa1.1-@var{any}-@var{any}}
923 @item @samp{sparc-sun-solaris2.@var{any}}
924 @item @samp{sparc64-@var{any}-solaris2.@var{any}}
925 @end itemize
926
927 @item @anchor{with-as}--with-as=@var{pathname}
928 Specify that the compiler should use the assembler pointed to by
929 @var{pathname}, rather than the one found by the standard rules to find
930 an assembler, which are:
931 @itemize @bullet
932 @item
933 Unless GCC is being built with a cross compiler, check the
934 @file{@var{libexec}/gcc/@var{target}/@var{version}} directory.
935 @var{libexec} defaults to @file{@var{exec-prefix}/libexec};
936 @var{exec-prefix} defaults to @var{prefix}, which
937 defaults to @file{/usr/local} unless overridden by the
938 @option{--prefix=@var{pathname}} switch described above. @var{target}
939 is the target system triple, such as @samp{sparc-sun-solaris2.7}, and
940 @var{version} denotes the GCC version, such as 3.0.
941
942 @item
943 If the target system is the same that you are building on, check
944 operating system specific directories (e.g.@: @file{/usr/ccs/bin} on
945 Sun Solaris 2).
946
947 @item
948 Check in the @env{PATH} for a tool whose name is prefixed by the
949 target system triple.
950
951 @item
952 Check in the @env{PATH} for a tool whose name is not prefixed by the
953 target system triple, if the host and target system triple are
954 the same (in other words, we use a host tool if it can be used for
955 the target as well).
956 @end itemize
957
958 You may want to use @option{--with-as} if no assembler
959 is installed in the directories listed above, or if you have multiple
960 assemblers installed and want to choose one that is not found by the
961 above rules.
962
963 @item @anchor{with-gnu-ld}--with-gnu-ld
964 Same as @uref{#with-gnu-as,,@option{--with-gnu-as}}
965 but for the linker.
966
967 @item --with-ld=@var{pathname}
968 Same as @uref{#with-as,,@option{--with-as}}
969 but for the linker.
970
971 @item --with-stabs
972 Specify that stabs debugging
973 information should be used instead of whatever format the host normally
974 uses. Normally GCC uses the same debug format as the host system.
975
976 On MIPS based systems and on Alphas, you must specify whether you want
977 GCC to create the normal ECOFF debugging format, or to use BSD-style
978 stabs passed through the ECOFF symbol table. The normal ECOFF debug
979 format cannot fully handle languages other than C@. BSD stabs format can
980 handle other languages, but it only works with the GNU debugger GDB@.
981
982 Normally, GCC uses the ECOFF debugging format by default; if you
983 prefer BSD stabs, specify @option{--with-stabs} when you configure GCC@.
984
985 No matter which default you choose when you configure GCC, the user
986 can use the @option{-gcoff} and @option{-gstabs+} options to specify explicitly
987 the debug format for a particular compilation.
988
989 @option{--with-stabs} is meaningful on the ISC system on the 386, also, if
990 @option{--with-gas} is used. It selects use of stabs debugging
991 information embedded in COFF output. This kind of debugging information
992 supports C++ well; ordinary COFF debugging information does not.
993
994 @option{--with-stabs} is also meaningful on 386 systems running SVR4. It
995 selects use of stabs debugging information embedded in ELF output. The
996 C++ compiler currently (2.6.0) does not support the DWARF debugging
997 information normally used on 386 SVR4 platforms; stabs provide a
998 workable alternative. This requires gas and gdb, as the normal SVR4
999 tools can not generate or interpret stabs.
1000
1001 @item --disable-multilib
1002 Specify that multiple target
1003 libraries to support different target variants, calling
1004 conventions, etc.@: should not be built. The default is to build a
1005 predefined set of them.
1006
1007 Some targets provide finer-grained control over which multilibs are built
1008 (e.g., @option{--disable-softfloat}):
1009 @table @code
1010 @item arc-*-elf*
1011 biendian.
1012
1013 @item arm-*-*
1014 fpu, 26bit, underscore, interwork, biendian, nofmult.
1015
1016 @item m68*-*-*
1017 softfloat, m68881, m68000, m68020.
1018
1019 @item mips*-*-*
1020 single-float, biendian, softfloat.
1021
1022 @item powerpc*-*-*, rs6000*-*-*
1023 aix64, pthread, softfloat, powercpu, powerpccpu, powerpcos, biendian,
1024 sysv, aix.
1025
1026 @end table
1027
1028 @item --with-multilib-list=@var{list}
1029 @itemx --without-multilib-list
1030 Specify what multilibs to build.
1031 Currently only implemented for sh*-*-*.
1032
1033 @var{list} is a comma separated list of CPU names. These must be of the
1034 form @code{sh*} or @code{m*} (in which case they match the compiler option
1035 for that processor). The list should not contain any endian options -
1036 these are handled by @option{--with-endian}.
1037
1038 If @var{list} is empty, then there will be no multilibs for extra
1039 processors. The multilib for the secondary endian remains enabled.
1040
1041 As a special case, if an entry in the list starts with a @code{!}
1042 (exclamation point), then it is added to the list of excluded multilibs.
1043 Entries of this sort should be compatible with @samp{MULTILIB_EXCLUDES}
1044 (once the leading @code{!} has been stripped).
1045
1046 If @option{--with-multilib-list} is not given, then a default set of
1047 multilibs is selected based on the value of @option{--target}. This is
1048 usually the complete set of libraries, but some targets imply a more
1049 specialized subset.
1050
1051 Example 1: to configure a compiler for SH4A only, but supporting both
1052 endians, with little endian being the default:
1053 @smallexample
1054 --with-cpu=sh4a --with-endian=little,big --with-multilib-list=
1055 @end smallexample
1056
1057 Example 2: to configure a compiler for both SH4A and SH4AL-DSP, but with
1058 only little endian SH4AL:
1059 @smallexample
1060 --with-cpu=sh4a --with-endian=little,big --with-multilib-list=sh4al,!mb/m4al
1061 @end smallexample
1062
1063 @item --with-endian=@var{endians}
1064 Specify what endians to use.
1065 Currently only implemented for sh*-*-*.
1066
1067 @var{endians} may be one of the following:
1068 @table @code
1069 @item big
1070 Use big endian exclusively.
1071 @item little
1072 Use little endian exclusively.
1073 @item big,little
1074 Use big endian by default. Provide a multilib for little endian.
1075 @item little,big
1076 Use little endian by default. Provide a multilib for big endian.
1077 @end table
1078
1079 @item --enable-threads
1080 Specify that the target
1081 supports threads. This affects the Objective-C compiler and runtime
1082 library, and exception handling for other languages like C++ and Java.
1083 On some systems, this is the default.
1084
1085 In general, the best (and, in many cases, the only known) threading
1086 model available will be configured for use. Beware that on some
1087 systems, GCC has not been taught what threading models are generally
1088 available for the system. In this case, @option{--enable-threads} is an
1089 alias for @option{--enable-threads=single}.
1090
1091 @item --disable-threads
1092 Specify that threading support should be disabled for the system.
1093 This is an alias for @option{--enable-threads=single}.
1094
1095 @item --enable-threads=@var{lib}
1096 Specify that
1097 @var{lib} is the thread support library. This affects the Objective-C
1098 compiler and runtime library, and exception handling for other languages
1099 like C++ and Java. The possibilities for @var{lib} are:
1100
1101 @table @code
1102 @item aix
1103 AIX thread support.
1104 @item dce
1105 DCE thread support.
1106 @item gnat
1107 Ada tasking support. For non-Ada programs, this setting is equivalent
1108 to @samp{single}. When used in conjunction with the Ada run time, it
1109 causes GCC to use the same thread primitives as Ada uses. This option
1110 is necessary when using both Ada and the back end exception handling,
1111 which is the default for most Ada targets.
1112 @item mach
1113 Generic MACH thread support, known to work on NeXTSTEP@. (Please note
1114 that the file needed to support this configuration, @file{gthr-mach.h}, is
1115 missing and thus this setting will cause a known bootstrap failure.)
1116 @item no
1117 This is an alias for @samp{single}.
1118 @item posix
1119 Generic POSIX/Unix98 thread support.
1120 @item posix95
1121 Generic POSIX/Unix95 thread support.
1122 @item rtems
1123 RTEMS thread support.
1124 @item single
1125 Disable thread support, should work for all platforms.
1126 @item solaris
1127 Sun Solaris 2/Unix International thread support. Only use this if you
1128 really need to use this legacy API instead of the default, @samp{posix}.
1129 @item vxworks
1130 VxWorks thread support.
1131 @item win32
1132 Microsoft Win32 API thread support.
1133 @item nks
1134 Novell Kernel Services thread support.
1135 @end table
1136
1137 @item --enable-tls
1138 Specify that the target supports TLS (Thread Local Storage). Usually
1139 configure can correctly determine if TLS is supported. In cases where
1140 it guesses incorrectly, TLS can be explicitly enabled or disabled with
1141 @option{--enable-tls} or @option{--disable-tls}. This can happen if
1142 the assembler supports TLS but the C library does not, or if the
1143 assumptions made by the configure test are incorrect.
1144
1145 @item --disable-tls
1146 Specify that the target does not support TLS.
1147 This is an alias for @option{--enable-tls=no}.
1148
1149 @item --with-cpu=@var{cpu}
1150 @itemx --with-cpu-32=@var{cpu}
1151 @itemx --with-cpu-64=@var{cpu}
1152 Specify which cpu variant the compiler should generate code for by default.
1153 @var{cpu} will be used as the default value of the @option{-mcpu=} switch.
1154 This option is only supported on some targets, including ARM, i386, M68k,
1155 PowerPC, and SPARC@. The @option{--with-cpu-32} and
1156 @option{--with-cpu-64} options specify separate default CPUs for
1157 32-bit and 64-bit modes; these options are only supported for i386,
1158 x86-64 and PowerPC.
1159
1160 @item --with-schedule=@var{cpu}
1161 @itemx --with-arch=@var{cpu}
1162 @itemx --with-arch-32=@var{cpu}
1163 @itemx --with-arch-64=@var{cpu}
1164 @itemx --with-tune=@var{cpu}
1165 @itemx --with-tune-32=@var{cpu}
1166 @itemx --with-tune-64=@var{cpu}
1167 @itemx --with-abi=@var{abi}
1168 @itemx --with-fpu=@var{type}
1169 @itemx --with-float=@var{type}
1170 These configure options provide default values for the @option{-mschedule=},
1171 @option{-march=}, @option{-mtune=}, @option{-mabi=}, and @option{-mfpu=}
1172 options and for @option{-mhard-float} or @option{-msoft-float}. As with
1173 @option{--with-cpu}, which switches will be accepted and acceptable values
1174 of the arguments depend on the target.
1175
1176 @item --with-mode=@var{mode}
1177 Specify if the compiler should default to @option{-marm} or @option{-mthumb}.
1178 This option is only supported on ARM targets.
1179
1180 @item --with-fpmath=sse
1181 Specify if the compiler should default to @option{-msse2} and
1182 @option{-mfpmath=sse}. This option is only supported on i386 and
1183 x86-64 targets.
1184
1185 @item --with-divide=@var{type}
1186 Specify how the compiler should generate code for checking for
1187 division by zero. This option is only supported on the MIPS target.
1188 The possibilities for @var{type} are:
1189 @table @code
1190 @item traps
1191 Division by zero checks use conditional traps (this is the default on
1192 systems that support conditional traps).
1193 @item breaks
1194 Division by zero checks use the break instruction.
1195 @end table
1196
1197 @c If you make --with-llsc the default for additional targets,
1198 @c update the --with-llsc description in the MIPS section below.
1199
1200 @item --with-llsc
1201 On MIPS targets, make @option{-mllsc} the default when no
1202 @option{-mno-lsc} option is passed. This is the default for
1203 Linux-based targets, as the kernel will emulate them if the ISA does
1204 not provide them.
1205
1206 @item --without-llsc
1207 On MIPS targets, make @option{-mno-llsc} the default when no
1208 @option{-mllsc} option is passed.
1209
1210 @item --with-synci
1211 On MIPS targets, make @option{-msynci} the default when no
1212 @option{-mno-synci} option is passed.
1213
1214 @item --without-synci
1215 On MIPS targets, make @option{-mno-synci} the default when no
1216 @option{-msynci} option is passed. This is the default.
1217
1218 @item --with-mips-plt
1219 On MIPS targets, make use of copy relocations and PLTs.
1220 These features are extensions to the traditional
1221 SVR4-based MIPS ABIs and require support from GNU binutils
1222 and the runtime C library.
1223
1224 @item --enable-__cxa_atexit
1225 Define if you want to use __cxa_atexit, rather than atexit, to
1226 register C++ destructors for local statics and global objects.
1227 This is essential for fully standards-compliant handling of
1228 destructors, but requires __cxa_atexit in libc. This option is currently
1229 only available on systems with GNU libc. When enabled, this will cause
1230 @option{-fuse-cxa-atexit} to be passed by default.
1231
1232 @item --enable-indirect-function
1233 Define if you want to enable the @code{ifunc} attribute. This option is
1234 currently only available on systems with GNU libc on certain targets.
1235
1236 @item --enable-target-optspace
1237 Specify that target
1238 libraries should be optimized for code space instead of code speed.
1239 This is the default for the m32r platform.
1240
1241 @item --with-cpp-install-dir=@var{dirname}
1242 Specify that the user visible @command{cpp} program should be installed
1243 in @file{@var{prefix}/@var{dirname}/cpp}, in addition to @var{bindir}.
1244
1245 @item --enable-comdat
1246 Enable COMDAT group support. This is primarily used to override the
1247 automatically detected value.
1248
1249 @item --enable-initfini-array
1250 Force the use of sections @code{.init_array} and @code{.fini_array}
1251 (instead of @code{.init} and @code{.fini}) for constructors and
1252 destructors. Option @option{--disable-initfini-array} has the
1253 opposite effect. If neither option is specified, the configure script
1254 will try to guess whether the @code{.init_array} and
1255 @code{.fini_array} sections are supported and, if they are, use them.
1256
1257 @item --enable-build-with-cxx
1258 Build GCC using a C++ compiler rather than a C compiler. This is an
1259 experimental option which may become the default in a later release.
1260
1261 @item --enable-maintainer-mode
1262 The build rules that regenerate the Autoconf and Automake output files as
1263 well as the GCC master message catalog @file{gcc.pot} are normally
1264 disabled. This is because it can only be rebuilt if the complete source
1265 tree is present. If you have changed the sources and want to rebuild the
1266 catalog, configuring with @option{--enable-maintainer-mode} will enable
1267 this. Note that you need a recent version of the @code{gettext} tools
1268 to do so.
1269
1270 @item --disable-bootstrap
1271 For a native build, the default configuration is to perform
1272 a 3-stage bootstrap of the compiler when @samp{make} is invoked,
1273 testing that GCC can compile itself correctly. If you want to disable
1274 this process, you can configure with @option{--disable-bootstrap}.
1275
1276 @item --enable-bootstrap
1277 In special cases, you may want to perform a 3-stage build
1278 even if the target and host triplets are different.
1279 This is possible when the host can run code compiled for
1280 the target (e.g.@: host is i686-linux, target is i486-linux).
1281 Starting from GCC 4.2, to do this you have to configure explicitly
1282 with @option{--enable-bootstrap}.
1283
1284 @item --enable-generated-files-in-srcdir
1285 Neither the .c and .h files that are generated from Bison and flex nor the
1286 info manuals and man pages that are built from the .texi files are present
1287 in the SVN development tree. When building GCC from that development tree,
1288 or from one of our snapshots, those generated files are placed in your
1289 build directory, which allows for the source to be in a readonly
1290 directory.
1291
1292 If you configure with @option{--enable-generated-files-in-srcdir} then those
1293 generated files will go into the source directory. This is mainly intended
1294 for generating release or prerelease tarballs of the GCC sources, since it
1295 is not a requirement that the users of source releases to have flex, Bison,
1296 or makeinfo.
1297
1298 @item --enable-version-specific-runtime-libs
1299 Specify
1300 that runtime libraries should be installed in the compiler specific
1301 subdirectory (@file{@var{libdir}/gcc}) rather than the usual places. In
1302 addition, @samp{libstdc++}'s include files will be installed into
1303 @file{@var{libdir}} unless you overruled it by using
1304 @option{--with-gxx-include-dir=@var{dirname}}. Using this option is
1305 particularly useful if you intend to use several versions of GCC in
1306 parallel. This is currently supported by @samp{libgfortran},
1307 @samp{libjava}, @samp{libmudflap}, @samp{libstdc++}, and @samp{libobjc}.
1308
1309 @item --enable-languages=@var{lang1},@var{lang2},@dots{}
1310 Specify that only a particular subset of compilers and
1311 their runtime libraries should be built. For a list of valid values for
1312 @var{langN} you can issue the following command in the
1313 @file{gcc} directory of your GCC source tree:@*
1314 @smallexample
1315 grep language= */config-lang.in
1316 @end smallexample
1317 Currently, you can use any of the following:
1318 @code{all}, @code{ada}, @code{c}, @code{c++}, @code{fortran}, @code{java},
1319 @code{objc}, @code{obj-c++}.
1320 Building the Ada compiler has special requirements, see below.
1321 If you do not pass this flag, or specify the option @code{all}, then all
1322 default languages available in the @file{gcc} sub-tree will be configured.
1323 Ada and Objective-C++ are not default languages; the rest are.
1324 Re-defining @code{LANGUAGES} when calling @samp{make} @strong{does not}
1325 work anymore, as those language sub-directories might not have been
1326 configured!
1327
1328 @item --enable-stage1-languages=@var{lang1},@var{lang2},@dots{}
1329 Specify that a particular subset of compilers and their runtime
1330 libraries should be built with the system C compiler during stage 1 of
1331 the bootstrap process, rather than only in later stages with the
1332 bootstrapped C compiler. The list of valid values is the same as for
1333 @option{--enable-languages}, and the option @code{all} will select all
1334 of the languages enabled by @option{--enable-languages}. This option is
1335 primarily useful for GCC development; for instance, when a development
1336 version of the compiler cannot bootstrap due to compiler bugs, or when
1337 one is debugging front ends other than the C front end. When this
1338 option is used, one can then build the target libraries for the
1339 specified languages with the stage-1 compiler by using @command{make
1340 stage1-bubble all-target}, or run the testsuite on the stage-1 compiler
1341 for the specified languages using @command{make stage1-start check-gcc}.
1342
1343 @item --disable-libada
1344 Specify that the run-time libraries and tools used by GNAT should not
1345 be built. This can be useful for debugging, or for compatibility with
1346 previous Ada build procedures, when it was required to explicitly
1347 do a @samp{make -C gcc gnatlib_and_tools}.
1348
1349 @item --disable-libssp
1350 Specify that the run-time libraries for stack smashing protection
1351 should not be built.
1352
1353 @item --disable-libgomp
1354 Specify that the run-time libraries used by GOMP should not be built.
1355
1356 @item --with-dwarf2
1357 Specify that the compiler should
1358 use DWARF 2 debugging information as the default.
1359
1360 @item --enable-targets=all
1361 @itemx --enable-targets=@var{target_list}
1362 Some GCC targets, e.g.@: powerpc64-linux, build bi-arch compilers.
1363 These are compilers that are able to generate either 64-bit or 32-bit
1364 code. Typically, the corresponding 32-bit target, e.g.@:
1365 powerpc-linux for powerpc64-linux, only generates 32-bit code. This
1366 option enables the 32-bit target to be a bi-arch compiler, which is
1367 useful when you want a bi-arch compiler that defaults to 32-bit, and
1368 you are building a bi-arch or multi-arch binutils in a combined tree.
1369 On mips-linux, this will build a tri-arch compiler (ABI o32/n32/64),
1370 defaulted to o32.
1371 Currently, this option only affects sparc-linux, powerpc-linux, x86-linux
1372 and mips-linux.
1373
1374 @item --enable-secureplt
1375 This option enables @option{-msecure-plt} by default for powerpc-linux.
1376 @ifnothtml
1377 @xref{RS/6000 and PowerPC Options,, RS/6000 and PowerPC Options, gcc,
1378 Using the GNU Compiler Collection (GCC)},
1379 @end ifnothtml
1380 @ifhtml
1381 See ``RS/6000 and PowerPC Options'' in the main manual
1382 @end ifhtml
1383
1384 @item --enable-cld
1385 This option enables @option{-mcld} by default for 32-bit x86 targets.
1386 @ifnothtml
1387 @xref{i386 and x86-64 Options,, i386 and x86-64 Options, gcc,
1388 Using the GNU Compiler Collection (GCC)},
1389 @end ifnothtml
1390 @ifhtml
1391 See ``i386 and x86-64 Options'' in the main manual
1392 @end ifhtml
1393
1394 @item --enable-win32-registry
1395 @itemx --enable-win32-registry=@var{key}
1396 @itemx --disable-win32-registry
1397 The @option{--enable-win32-registry} option enables Microsoft Windows-hosted GCC
1398 to look up installations paths in the registry using the following key:
1399
1400 @smallexample
1401 @code{HKEY_LOCAL_MACHINE\SOFTWARE\Free Software Foundation\@var{key}}
1402 @end smallexample
1403
1404 @var{key} defaults to GCC version number, and can be overridden by the
1405 @option{--enable-win32-registry=@var{key}} option. Vendors and distributors
1406 who use custom installers are encouraged to provide a different key,
1407 perhaps one comprised of vendor name and GCC version number, to
1408 avoid conflict with existing installations. This feature is enabled
1409 by default, and can be disabled by @option{--disable-win32-registry}
1410 option. This option has no effect on the other hosts.
1411
1412 @item --nfp
1413 Specify that the machine does not have a floating point unit. This
1414 option only applies to @samp{m68k-sun-sunos@var{n}}. On any other
1415 system, @option{--nfp} has no effect.
1416
1417 @item --enable-werror
1418 @itemx --disable-werror
1419 @itemx --enable-werror=yes
1420 @itemx --enable-werror=no
1421 When you specify this option, it controls whether certain files in the
1422 compiler are built with @option{-Werror} in bootstrap stage2 and later.
1423 If you don't specify it, @option{-Werror} is turned on for the main
1424 development trunk. However it defaults to off for release branches and
1425 final releases. The specific files which get @option{-Werror} are
1426 controlled by the Makefiles.
1427
1428 @item --enable-checking
1429 @itemx --enable-checking=@var{list}
1430 When you specify this option, the compiler is built to perform internal
1431 consistency checks of the requested complexity. This does not change the
1432 generated code, but adds error checking within the compiler. This will
1433 slow down the compiler and may only work properly if you are building
1434 the compiler with GCC@. This is @samp{yes} by default when building
1435 from SVN or snapshots, but @samp{release} for releases. The default
1436 for building the stage1 compiler is @samp{yes}. More control
1437 over the checks may be had by specifying @var{list}. The categories of
1438 checks available are @samp{yes} (most common checks
1439 @samp{assert,misc,tree,gc,rtlflag,runtime}), @samp{no} (no checks at
1440 all), @samp{all} (all but @samp{valgrind}), @samp{release} (cheapest
1441 checks @samp{assert,runtime}) or @samp{none} (same as @samp{no}).
1442 Individual checks can be enabled with these flags @samp{assert},
1443 @samp{df}, @samp{fold}, @samp{gc}, @samp{gcac} @samp{misc}, @samp{rtl},
1444 @samp{rtlflag}, @samp{runtime}, @samp{tree}, and @samp{valgrind}.
1445
1446 The @samp{valgrind} check requires the external @command{valgrind}
1447 simulator, available from @uref{http://valgrind.org/}. The
1448 @samp{df}, @samp{rtl}, @samp{gcac} and @samp{valgrind} checks are very expensive.
1449 To disable all checking, @samp{--disable-checking} or
1450 @samp{--enable-checking=none} must be explicitly requested. Disabling
1451 assertions will make the compiler and runtime slightly faster but
1452 increase the risk of undetected internal errors causing wrong code to be
1453 generated.
1454
1455 @item --disable-stage1-checking
1456 @itemx --enable-stage1-checking
1457 @itemx --enable-stage1-checking=@var{list}
1458 If no @option{--enable-checking} option is specified the stage1
1459 compiler will be built with @samp{yes} checking enabled, otherwise
1460 the stage1 checking flags are the same as specified by
1461 @option{--enable-checking}. To build the stage1 compiler with
1462 different checking options use @option{--enable-stage1-checking}.
1463 The list of checking options is the same as for @option{--enable-checking}.
1464 If your system is too slow or too small to bootstrap a released compiler
1465 with checking for stage1 enabled, you can use @samp{--disable-stage1-checking}
1466 to disable checking for the stage1 compiler.
1467
1468 @item --enable-coverage
1469 @itemx --enable-coverage=@var{level}
1470 With this option, the compiler is built to collect self coverage
1471 information, every time it is run. This is for internal development
1472 purposes, and only works when the compiler is being built with gcc. The
1473 @var{level} argument controls whether the compiler is built optimized or
1474 not, values are @samp{opt} and @samp{noopt}. For coverage analysis you
1475 want to disable optimization, for performance analysis you want to
1476 enable optimization. When coverage is enabled, the default level is
1477 without optimization.
1478
1479 @item --enable-gather-detailed-mem-stats
1480 When this option is specified more detailed information on memory
1481 allocation is gathered. This information is printed when using
1482 @option{-fmem-report}.
1483
1484 @item --with-gc
1485 @itemx --with-gc=@var{choice}
1486 With this option you can specify the garbage collector implementation
1487 used during the compilation process. @var{choice} can be one of
1488 @samp{page} and @samp{zone}, where @samp{page} is the default.
1489
1490 @item --enable-nls
1491 @itemx --disable-nls
1492 The @option{--enable-nls} option enables Native Language Support (NLS),
1493 which lets GCC output diagnostics in languages other than American
1494 English. Native Language Support is enabled by default if not doing a
1495 canadian cross build. The @option{--disable-nls} option disables NLS@.
1496
1497 @item --with-included-gettext
1498 If NLS is enabled, the @option{--with-included-gettext} option causes the build
1499 procedure to prefer its copy of GNU @command{gettext}.
1500
1501 @item --with-catgets
1502 If NLS is enabled, and if the host lacks @code{gettext} but has the
1503 inferior @code{catgets} interface, the GCC build procedure normally
1504 ignores @code{catgets} and instead uses GCC's copy of the GNU
1505 @code{gettext} library. The @option{--with-catgets} option causes the
1506 build procedure to use the host's @code{catgets} in this situation.
1507
1508 @item --with-libiconv-prefix=@var{dir}
1509 Search for libiconv header files in @file{@var{dir}/include} and
1510 libiconv library files in @file{@var{dir}/lib}.
1511
1512 @item --enable-obsolete
1513 Enable configuration for an obsoleted system. If you attempt to
1514 configure GCC for a system (build, host, or target) which has been
1515 obsoleted, and you do not specify this flag, configure will halt with an
1516 error message.
1517
1518 All support for systems which have been obsoleted in one release of GCC
1519 is removed entirely in the next major release, unless someone steps
1520 forward to maintain the port.
1521
1522 @item --enable-decimal-float
1523 @itemx --enable-decimal-float=yes
1524 @itemx --enable-decimal-float=no
1525 @itemx --enable-decimal-float=bid
1526 @itemx --enable-decimal-float=dpd
1527 @itemx --disable-decimal-float
1528 Enable (or disable) support for the C decimal floating point extension
1529 that is in the IEEE 754-2008 standard. This is enabled by default only
1530 on PowerPC, i386, and x86_64 GNU/Linux systems. Other systems may also
1531 support it, but require the user to specifically enable it. You can
1532 optionally control which decimal floating point format is used (either
1533 @samp{bid} or @samp{dpd}). The @samp{bid} (binary integer decimal)
1534 format is default on i386 and x86_64 systems, and the @samp{dpd}
1535 (densely packed decimal) format is default on PowerPC systems.
1536
1537 @item --enable-fixed-point
1538 @itemx --disable-fixed-point
1539 Enable (or disable) support for C fixed-point arithmetic.
1540 This option is enabled by default for some targets (such as MIPS) which
1541 have hardware-support for fixed-point operations. On other targets, you
1542 may enable this option manually.
1543
1544 @item --with-long-double-128
1545 Specify if @code{long double} type should be 128-bit by default on selected
1546 GNU/Linux architectures. If using @code{--without-long-double-128},
1547 @code{long double} will be by default 64-bit, the same as @code{double} type.
1548 When neither of these configure options are used, the default will be
1549 128-bit @code{long double} when built against GNU C Library 2.4 and later,
1550 64-bit @code{long double} otherwise.
1551
1552 @item --with-gmp=@var{pathname}
1553 @itemx --with-gmp-include=@var{pathname}
1554 @itemx --with-gmp-lib=@var{pathname}
1555 @itemx --with-mpfr=@var{pathname}
1556 @itemx --with-mpfr-include=@var{pathname}
1557 @itemx --with-mpfr-lib=@var{pathname}
1558 @itemx --with-mpc=@var{pathname}
1559 @itemx --with-mpc-include=@var{pathname}
1560 @itemx --with-mpc-lib=@var{pathname}
1561 If you do not have GMP (the GNU Multiple Precision library), the MPFR
1562 library and/or the MPC library installed in a standard location and
1563 you want to build GCC, you can explicitly specify the directory where
1564 they are installed (@samp{--with-gmp=@var{gmpinstalldir}},
1565 @samp{--with-mpfr=@var{mpfrinstalldir}},
1566 @samp{--with-mpc=@var{mpcinstalldir}}). The
1567 @option{--with-gmp=@var{gmpinstalldir}} option is shorthand for
1568 @option{--with-gmp-lib=@var{gmpinstalldir}/lib} and
1569 @option{--with-gmp-include=@var{gmpinstalldir}/include}. Likewise the
1570 @option{--with-mpfr=@var{mpfrinstalldir}} option is shorthand for
1571 @option{--with-mpfr-lib=@var{mpfrinstalldir}/lib} and
1572 @option{--with-mpfr-include=@var{mpfrinstalldir}/include}, also the
1573 @option{--with-mpc=@var{mpcinstalldir}} option is shorthand for
1574 @option{--with-mpc-lib=@var{mpcinstalldir}/lib} and
1575 @option{--with-mpc-include=@var{mpcinstalldir}/include}. If these
1576 shorthand assumptions are not correct, you can use the explicit
1577 include and lib options directly. You might also need to ensure the
1578 shared libraries can be found by the dynamic linker when building and
1579 using GCC, for example by setting the runtime shared library path
1580 variable (@env{LD_LIBRARY_PATH} on GNU/Linux and Solaris systems).
1581
1582 @item --with-ppl=@var{pathname}
1583 @itemx --with-ppl-include=@var{pathname}
1584 @itemx --with-ppl-lib=@var{pathname}
1585 @itemx --with-cloog=@var{pathname}
1586 @itemx --with-cloog-include=@var{pathname}
1587 @itemx --with-cloog-lib=@var{pathname}
1588 If you do not have PPL (the Parma Polyhedra Library) and the CLooG
1589 libraries installed in a standard location and you want to build GCC,
1590 you can explicitly specify the directory where they are installed
1591 (@samp{--with-ppl=@var{pplinstalldir}},
1592 @samp{--with-cloog=@var{clooginstalldir}}). The
1593 @option{--with-ppl=@var{pplinstalldir}} option is shorthand for
1594 @option{--with-ppl-lib=@var{pplinstalldir}/lib} and
1595 @option{--with-ppl-include=@var{pplinstalldir}/include}. Likewise the
1596 @option{--with-cloog=@var{clooginstalldir}} option is shorthand for
1597 @option{--with-cloog-lib=@var{clooginstalldir}/lib} and
1598 @option{--with-cloog-include=@var{clooginstalldir}/include}. If these
1599 shorthand assumptions are not correct, you can use the explicit
1600 include and lib options directly.
1601
1602 @item --with-host-libstdcxx=@var{linker-args}
1603 If you are linking with a static copy of PPL, you can use this option
1604 to specify how the linker should find the standard C++ library used
1605 internally by PPL. Typical values of @var{linker-args} might be
1606 @samp{-lstdc++} or @samp{-Wl,-Bstatic,-lstdc++,-Bdynamic -lm}. If you are
1607 linking with a shared copy of PPL, you probably do not need this
1608 option; shared library dependencies will cause the linker to search
1609 for the standard C++ library automatically.
1610
1611 @item --with-stage1-ldflags=@var{flags}
1612 This option may be used to set linker flags to be used when linking
1613 stage 1 of GCC. These are also used when linking GCC if configured with
1614 @option{--disable-bootstrap}. By default no special flags are used.
1615
1616 @item --with-stage1-libs=@var{libs}
1617 This option may be used to set libraries to be used when linking stage 1
1618 of GCC. These are also used when linking GCC if configured with
1619 @option{--disable-bootstrap}. The default is the argument to
1620 @option{--with-host-libstdcxx}, if specified.
1621
1622 @item --with-boot-ldflags=@var{flags}
1623 This option may be used to set linker flags to be used when linking
1624 stage 2 and later when bootstrapping GCC. By default no special flags
1625 are used.
1626
1627 @item --with-boot-libs=@var{libs}
1628 This option may be used to set libraries to be used when linking stage 2
1629 and later when bootstrapping GCC. The default is the argument to
1630 @option{--with-host-libstdcxx}, if specified.
1631
1632 @item --with-debug-prefix-map=@var{map}
1633 Convert source directory names using @option{-fdebug-prefix-map} when
1634 building runtime libraries. @samp{@var{map}} is a space-separated
1635 list of maps of the form @samp{@var{old}=@var{new}}.
1636
1637 @item --enable-linker-build-id
1638 Tells GCC to pass @option{--build-id} option to the linker for all final
1639 links (links performed without the @option{-r} or @option{--relocatable}
1640 option), if the linker supports it. If you specify
1641 @option{--enable-linker-build-id}, but your linker does not
1642 support @option{--build-id} option, a warning is issued and the
1643 @option{--enable-linker-build-id} option is ignored. The default is off.
1644
1645 @item --enable-gnu-unique-object
1646 @itemx --disable-gnu-unique-object
1647 Tells GCC to use the gnu_unique_object relocation for C++ template
1648 static data members and inline function local statics. Enabled by
1649 default for a native toolchain with an assembler that accepts it and
1650 GLIBC 2.11 or above, otherwise disabled.
1651
1652 @item --enable-lto
1653 Enable support for link-time optimization (LTO). This is enabled by
1654 default if a working libelf implementation is found (see
1655 @option{--with-libelf}).
1656
1657 @item --with-libelf=@var{pathname}
1658 @itemx --with-libelf-include=@var{pathname}
1659 @itemx --with-libelf-lib=@var{pathname}
1660 If you do not have libelf installed in a standard location and you
1661 want to enable support for link-time optimization (LTO), you can
1662 explicitly specify the directory where libelf is installed
1663 (@samp{--with-libelf=@var{libelfinstalldir}}). The
1664 @option{--with-libelf=@var{libelfinstalldir}} option is shorthand for
1665 @option{--with-libelf-include=@var{libelfinstalldir}/include}
1666 @option{--with-libelf-lib=@var{libelfinstalldir}/lib}.
1667
1668 @item --enable-gold
1669 Enable support for using @command{gold} as the linker. If gold support is
1670 enabled together with @option{--enable-lto}, an additional directory
1671 @file{lto-plugin} will be built. The code in this directory is a
1672 plugin for gold that allows the link-time optimizer to extract object
1673 files with LTO information out of library archives. See
1674 @option{-flto} and @option{-fwhopr} for details.
1675 @end table
1676
1677 @subheading Cross-Compiler-Specific Options
1678 The following options only apply to building cross compilers.
1679
1680 @table @code
1681 @item --with-sysroot
1682 @itemx --with-sysroot=@var{dir}
1683 Tells GCC to consider @var{dir} as the root of a tree that contains a
1684 (subset of) the root filesystem of the target operating system.
1685 Target system headers, libraries and run-time object files will be
1686 searched in there. More specifically, this acts as if
1687 @option{--sysroot=@var{dir}} was added to the default options of the built
1688 compiler. The specified directory is not copied into the
1689 install tree, unlike the options @option{--with-headers} and
1690 @option{--with-libs} that this option obsoletes. The default value,
1691 in case @option{--with-sysroot} is not given an argument, is
1692 @option{$@{gcc_tooldir@}/sys-root}. If the specified directory is a
1693 subdirectory of @option{$@{exec_prefix@}}, then it will be found relative to
1694 the GCC binaries if the installation tree is moved.
1695
1696 This option affects the system root for the compiler used to build
1697 target libraries (which runs on the build system) and the compiler newly
1698 installed with @code{make install}; it does not affect the compiler which is
1699 used to build GCC itself.
1700
1701 @item --with-build-sysroot
1702 @itemx --with-build-sysroot=@var{dir}
1703 Tells GCC to consider @var{dir} as the system root (see
1704 @option{--with-sysroot}) while building target libraries, instead of
1705 the directory specified with @option{--with-sysroot}. This option is
1706 only useful when you are already using @option{--with-sysroot}. You
1707 can use @option{--with-build-sysroot} when you are configuring with
1708 @option{--prefix} set to a directory that is different from the one in
1709 which you are installing GCC and your target libraries.
1710
1711 This option affects the system root for the compiler used to build
1712 target libraries (which runs on the build system); it does not affect
1713 the compiler which is used to build GCC itself.
1714
1715 @item --with-headers
1716 @itemx --with-headers=@var{dir}
1717 Deprecated in favor of @option{--with-sysroot}.
1718 Specifies that target headers are available when building a cross compiler.
1719 The @var{dir} argument specifies a directory which has the target include
1720 files. These include files will be copied into the @file{gcc} install
1721 directory. @emph{This option with the @var{dir} argument is required} when
1722 building a cross compiler, if @file{@var{prefix}/@var{target}/sys-include}
1723 doesn't pre-exist. If @file{@var{prefix}/@var{target}/sys-include} does
1724 pre-exist, the @var{dir} argument may be omitted. @command{fixincludes}
1725 will be run on these files to make them compatible with GCC@.
1726
1727 @item --without-headers
1728 Tells GCC not use any target headers from a libc when building a cross
1729 compiler. When crossing to GNU/Linux, you need the headers so GCC
1730 can build the exception handling for libgcc.
1731
1732 @item --with-libs
1733 @itemx --with-libs="@var{dir1} @var{dir2} @dots{} @var{dirN}"
1734 Deprecated in favor of @option{--with-sysroot}.
1735 Specifies a list of directories which contain the target runtime
1736 libraries. These libraries will be copied into the @file{gcc} install
1737 directory. If the directory list is omitted, this option has no
1738 effect.
1739
1740 @item --with-newlib
1741 Specifies that @samp{newlib} is
1742 being used as the target C library. This causes @code{__eprintf} to be
1743 omitted from @file{libgcc.a} on the assumption that it will be provided by
1744 @samp{newlib}.
1745
1746 @item --with-build-time-tools=@var{dir}
1747 Specifies where to find the set of target tools (assembler, linker, etc.)
1748 that will be used while building GCC itself. This option can be useful
1749 if the directory layouts are different between the system you are building
1750 GCC on, and the system where you will deploy it.
1751
1752 For example, on an @samp{ia64-hp-hpux} system, you may have the GNU
1753 assembler and linker in @file{/usr/bin}, and the native tools in a
1754 different path, and build a toolchain that expects to find the
1755 native tools in @file{/usr/bin}.
1756
1757 When you use this option, you should ensure that @var{dir} includes
1758 @command{ar}, @command{as}, @command{ld}, @command{nm},
1759 @command{ranlib} and @command{strip} if necessary, and possibly
1760 @command{objdump}. Otherwise, GCC may use an inconsistent set of
1761 tools.
1762 @end table
1763
1764 @subheading Java-Specific Options
1765
1766 The following option applies to the build of the Java front end.
1767
1768 @table @code
1769 @item --disable-libgcj
1770 Specify that the run-time libraries
1771 used by GCJ should not be built. This is useful in case you intend
1772 to use GCJ with some other run-time, or you're going to install it
1773 separately, or it just happens not to build on your particular
1774 machine. In general, if the Java front end is enabled, the GCJ
1775 libraries will be enabled too, unless they're known to not work on
1776 the target platform. If GCJ is enabled but @samp{libgcj} isn't built, you
1777 may need to port it; in this case, before modifying the top-level
1778 @file{configure.in} so that @samp{libgcj} is enabled by default on this platform,
1779 you may use @option{--enable-libgcj} to override the default.
1780
1781 @end table
1782
1783 The following options apply to building @samp{libgcj}.
1784
1785 @subsubheading General Options
1786
1787 @table @code
1788 @item --enable-java-maintainer-mode
1789 By default the @samp{libjava} build will not attempt to compile the
1790 @file{.java} source files to @file{.class}. Instead, it will use the
1791 @file{.class} files from the source tree. If you use this option you
1792 must have executables named @command{ecj1} and @command{gjavah} in your path
1793 for use by the build. You must use this option if you intend to
1794 modify any @file{.java} files in @file{libjava}.
1795
1796 @item --with-java-home=@var{dirname}
1797 This @samp{libjava} option overrides the default value of the
1798 @samp{java.home} system property. It is also used to set
1799 @samp{sun.boot.class.path} to @file{@var{dirname}/lib/rt.jar}. By
1800 default @samp{java.home} is set to @file{@var{prefix}} and
1801 @samp{sun.boot.class.path} to
1802 @file{@var{datadir}/java/libgcj-@var{version}.jar}.
1803
1804 @item --with-ecj-jar=@var{filename}
1805 This option can be used to specify the location of an external jar
1806 file containing the Eclipse Java compiler. A specially modified
1807 version of this compiler is used by @command{gcj} to parse
1808 @file{.java} source files. If this option is given, the
1809 @samp{libjava} build will create and install an @file{ecj1} executable
1810 which uses this jar file at runtime.
1811
1812 If this option is not given, but an @file{ecj.jar} file is found in
1813 the topmost source tree at configure time, then the @samp{libgcj}
1814 build will create and install @file{ecj1}, and will also install the
1815 discovered @file{ecj.jar} into a suitable place in the install tree.
1816
1817 If @file{ecj1} is not installed, then the user will have to supply one
1818 on his path in order for @command{gcj} to properly parse @file{.java}
1819 source files. A suitable jar is available from
1820 @uref{ftp://sourceware.org/pub/java/}.
1821
1822 @item --disable-getenv-properties
1823 Don't set system properties from @env{GCJ_PROPERTIES}.
1824
1825 @item --enable-hash-synchronization
1826 Use a global hash table for monitor locks. Ordinarily,
1827 @samp{libgcj}'s @samp{configure} script automatically makes
1828 the correct choice for this option for your platform. Only use
1829 this if you know you need the library to be configured differently.
1830
1831 @item --enable-interpreter
1832 Enable the Java interpreter. The interpreter is automatically
1833 enabled by default on all platforms that support it. This option
1834 is really only useful if you want to disable the interpreter
1835 (using @option{--disable-interpreter}).
1836
1837 @item --disable-java-net
1838 Disable java.net. This disables the native part of java.net only,
1839 using non-functional stubs for native method implementations.
1840
1841 @item --disable-jvmpi
1842 Disable JVMPI support.
1843
1844 @item --disable-libgcj-bc
1845 Disable BC ABI compilation of certain parts of libgcj. By default,
1846 some portions of libgcj are compiled with @option{-findirect-dispatch}
1847 and @option{-fno-indirect-classes}, allowing them to be overridden at
1848 run-time.
1849
1850 If @option{--disable-libgcj-bc} is specified, libgcj is built without
1851 these options. This allows the compile-time linker to resolve
1852 dependencies when statically linking to libgcj. However it makes it
1853 impossible to override the affected portions of libgcj at run-time.
1854
1855 @item --enable-reduced-reflection
1856 Build most of libgcj with @option{-freduced-reflection}. This reduces
1857 the size of libgcj at the expense of not being able to do accurate
1858 reflection on the classes it contains. This option is safe if you
1859 know that code using libgcj will never use reflection on the standard
1860 runtime classes in libgcj (including using serialization, RMI or CORBA).
1861
1862 @item --with-ecos
1863 Enable runtime eCos target support.
1864
1865 @item --without-libffi
1866 Don't use @samp{libffi}. This will disable the interpreter and JNI
1867 support as well, as these require @samp{libffi} to work.
1868
1869 @item --enable-libgcj-debug
1870 Enable runtime debugging code.
1871
1872 @item --enable-libgcj-multifile
1873 If specified, causes all @file{.java} source files to be
1874 compiled into @file{.class} files in one invocation of
1875 @samp{gcj}. This can speed up build time, but is more
1876 resource-intensive. If this option is unspecified or
1877 disabled, @samp{gcj} is invoked once for each @file{.java}
1878 file to compile into a @file{.class} file.
1879
1880 @item --with-libiconv-prefix=DIR
1881 Search for libiconv in @file{DIR/include} and @file{DIR/lib}.
1882
1883 @item --enable-sjlj-exceptions
1884 Force use of the @code{setjmp}/@code{longjmp}-based scheme for exceptions.
1885 @samp{configure} ordinarily picks the correct value based on the platform.
1886 Only use this option if you are sure you need a different setting.
1887
1888 @item --with-system-zlib
1889 Use installed @samp{zlib} rather than that included with GCC@.
1890
1891 @item --with-win32-nlsapi=ansi, unicows or unicode
1892 Indicates how MinGW @samp{libgcj} translates between UNICODE
1893 characters and the Win32 API@.
1894
1895 @item --enable-java-home
1896 If enabled, this creates a JPackage compatible SDK environment during install.
1897 Note that if --enable-java-home is used, --with-arch-directory=ARCH must also
1898 be specified.
1899
1900 @item --with-arch-directory=ARCH
1901 Specifies the name to use for the @file{jre/lib/ARCH} directory in the SDK
1902 environment created when --enable-java-home is passed. Typical names for this
1903 directory include i386, amd64, ia64, etc.
1904
1905 @item --with-os-directory=DIR
1906 Specifies the OS directory for the SDK include directory. This is set to auto
1907 detect, and is typically 'linux'.
1908
1909 @item --with-origin-name=NAME
1910 Specifies the JPackage origin name. This defaults to the 'gcj' in
1911 java-1.5.0-gcj.
1912
1913 @item --with-arch-suffix=SUFFIX
1914 Specifies the suffix for the sdk directory. Defaults to the empty string.
1915 Examples include '.x86_64' in 'java-1.5.0-gcj-1.5.0.0.x86_64'.
1916
1917 @item --with-jvm-root-dir=DIR
1918 Specifies where to install the SDK. Default is $(prefix)/lib/jvm.
1919
1920 @item --with-jvm-jar-dir=DIR
1921 Specifies where to install jars. Default is $(prefix)/lib/jvm-exports.
1922
1923 @item --with-python-dir=DIR
1924 Specifies where to install the Python modules used for aot-compile. DIR should
1925 not include the prefix used in installation. For example, if the Python modules
1926 are to be installed in /usr/lib/python2.5/site-packages, then
1927 --with-python-dir=/lib/python2.5/site-packages should be passed. If this is
1928 not specified, then the Python modules are installed in $(prefix)/share/python.
1929
1930 @item --enable-aot-compile-rpm
1931 Adds aot-compile-rpm to the list of installed scripts.
1932
1933 @item --enable-browser-plugin
1934 Build the gcjwebplugin web browser plugin.
1935
1936 @table @code
1937 @item ansi
1938 Use the single-byte @code{char} and the Win32 A functions natively,
1939 translating to and from UNICODE when using these functions. If
1940 unspecified, this is the default.
1941
1942 @item unicows
1943 Use the @code{WCHAR} and Win32 W functions natively. Adds
1944 @code{-lunicows} to @file{libgcj.spec} to link with @samp{libunicows}.
1945 @file{unicows.dll} needs to be deployed on Microsoft Windows 9X machines
1946 running built executables. @file{libunicows.a}, an open-source
1947 import library around Microsoft's @code{unicows.dll}, is obtained from
1948 @uref{http://libunicows.sourceforge.net/}, which also gives details
1949 on getting @file{unicows.dll} from Microsoft.
1950
1951 @item unicode
1952 Use the @code{WCHAR} and Win32 W functions natively. Does @emph{not}
1953 add @code{-lunicows} to @file{libgcj.spec}. The built executables will
1954 only run on Microsoft Windows NT and above.
1955 @end table
1956 @end table
1957
1958 @subsubheading AWT-Specific Options
1959
1960 @table @code
1961 @item --with-x
1962 Use the X Window System.
1963
1964 @item --enable-java-awt=PEER(S)
1965 Specifies the AWT peer library or libraries to build alongside
1966 @samp{libgcj}. If this option is unspecified or disabled, AWT
1967 will be non-functional. Current valid values are @option{gtk} and
1968 @option{xlib}. Multiple libraries should be separated by a
1969 comma (i.e.@: @option{--enable-java-awt=gtk,xlib}).
1970
1971 @item --enable-gtk-cairo
1972 Build the cairo Graphics2D implementation on GTK@.
1973
1974 @item --enable-java-gc=TYPE
1975 Choose garbage collector. Defaults to @option{boehm} if unspecified.
1976
1977 @item --disable-gtktest
1978 Do not try to compile and run a test GTK+ program.
1979
1980 @item --disable-glibtest
1981 Do not try to compile and run a test GLIB program.
1982
1983 @item --with-libart-prefix=PFX
1984 Prefix where libart is installed (optional).
1985
1986 @item --with-libart-exec-prefix=PFX
1987 Exec prefix where libart is installed (optional).
1988
1989 @item --disable-libarttest
1990 Do not try to compile and run a test libart program.
1991
1992 @end table
1993
1994 @html
1995 <hr />
1996 <p>
1997 @end html
1998 @ifhtml
1999 @uref{./index.html,,Return to the GCC Installation page}
2000 @end ifhtml
2001 @end ifset
2002
2003 @c ***Building****************************************************************
2004 @ifnothtml
2005 @comment node-name, next, previous, up
2006 @node Building, Testing, Configuration, Installing GCC
2007 @end ifnothtml
2008 @ifset buildhtml
2009 @ifnothtml
2010 @chapter Building
2011 @end ifnothtml
2012 @cindex Installing GCC: Building
2013
2014 Now that GCC is configured, you are ready to build the compiler and
2015 runtime libraries.
2016
2017 Some commands executed when making the compiler may fail (return a
2018 nonzero status) and be ignored by @command{make}. These failures, which
2019 are often due to files that were not found, are expected, and can safely
2020 be ignored.
2021
2022 It is normal to have compiler warnings when compiling certain files.
2023 Unless you are a GCC developer, you can generally ignore these warnings
2024 unless they cause compilation to fail. Developers should attempt to fix
2025 any warnings encountered, however they can temporarily continue past
2026 warnings-as-errors by specifying the configure flag
2027 @option{--disable-werror}.
2028
2029 On certain old systems, defining certain environment variables such as
2030 @env{CC} can interfere with the functioning of @command{make}.
2031
2032 If you encounter seemingly strange errors when trying to build the
2033 compiler in a directory other than the source directory, it could be
2034 because you have previously configured the compiler in the source
2035 directory. Make sure you have done all the necessary preparations.
2036
2037 If you build GCC on a BSD system using a directory stored in an old System
2038 V file system, problems may occur in running @command{fixincludes} if the
2039 System V file system doesn't support symbolic links. These problems
2040 result in a failure to fix the declaration of @code{size_t} in
2041 @file{sys/types.h}. If you find that @code{size_t} is a signed type and
2042 that type mismatches occur, this could be the cause.
2043
2044 The solution is not to use such a directory for building GCC@.
2045
2046 Similarly, when building from SVN or snapshots, or if you modify
2047 @file{*.l} files, you need the Flex lexical analyzer generator
2048 installed. If you do not modify @file{*.l} files, releases contain
2049 the Flex-generated files and you do not need Flex installed to build
2050 them. There is still one Flex-based lexical analyzer (part of the
2051 build machinery, not of GCC itself) that is used even if you only
2052 build the C front end.
2053
2054 When building from SVN or snapshots, or if you modify Texinfo
2055 documentation, you need version 4.7 or later of Texinfo installed if you
2056 want Info documentation to be regenerated. Releases contain Info
2057 documentation pre-built for the unmodified documentation in the release.
2058
2059 @section Building a native compiler
2060
2061 For a native build, the default configuration is to perform
2062 a 3-stage bootstrap of the compiler when @samp{make} is invoked.
2063 This will build the entire GCC system and ensure that it compiles
2064 itself correctly. It can be disabled with the @option{--disable-bootstrap}
2065 parameter to @samp{configure}, but bootstrapping is suggested because
2066 the compiler will be tested more completely and could also have
2067 better performance.
2068
2069 The bootstrapping process will complete the following steps:
2070
2071 @itemize @bullet
2072 @item
2073 Build tools necessary to build the compiler.
2074
2075 @item
2076 Perform a 3-stage bootstrap of the compiler. This includes building
2077 three times the target tools for use by the compiler such as binutils
2078 (bfd, binutils, gas, gprof, ld, and opcodes) if they have been
2079 individually linked or moved into the top level GCC source tree before
2080 configuring.
2081
2082 @item
2083 Perform a comparison test of the stage2 and stage3 compilers.
2084
2085 @item
2086 Build runtime libraries using the stage3 compiler from the previous step.
2087
2088 @end itemize
2089
2090 If you are short on disk space you might consider @samp{make
2091 bootstrap-lean} instead. The sequence of compilation is the
2092 same described above, but object files from the stage1 and
2093 stage2 of the 3-stage bootstrap of the compiler are deleted as
2094 soon as they are no longer needed.
2095
2096 If you wish to use non-default GCC flags when compiling the stage2
2097 and stage3 compilers, set @code{BOOT_CFLAGS} on the command line when
2098 doing @samp{make}. For example, if you want to save additional space
2099 during the bootstrap and in the final installation as well, you can
2100 build the compiler binaries without debugging information as in the
2101 following example. This will save roughly 40% of disk space both for
2102 the bootstrap and the final installation. (Libraries will still contain
2103 debugging information.)
2104
2105 @smallexample
2106 make BOOT_CFLAGS='-O' bootstrap
2107 @end smallexample
2108
2109 You can place non-default optimization flags into @code{BOOT_CFLAGS}; they
2110 are less well tested here than the default of @samp{-g -O2}, but should
2111 still work. In a few cases, you may find that you need to specify special
2112 flags such as @option{-msoft-float} here to complete the bootstrap; or,
2113 if the native compiler miscompiles the stage1 compiler, you may need
2114 to work around this, by choosing @code{BOOT_CFLAGS} to avoid the parts
2115 of the stage1 compiler that were miscompiled, or by using @samp{make
2116 bootstrap4} to increase the number of stages of bootstrap.
2117
2118 @code{BOOT_CFLAGS} does not apply to bootstrapped target libraries.
2119 Since these are always compiled with the compiler currently being
2120 bootstrapped, you can use @code{CFLAGS_FOR_TARGET} to modify their
2121 compilation flags, as for non-bootstrapped target libraries.
2122 Again, if the native compiler miscompiles the stage1 compiler, you may
2123 need to work around this by avoiding non-working parts of the stage1
2124 compiler. Use @code{STAGE1_TFLAGS} to this end.
2125
2126 If you used the flag @option{--enable-languages=@dots{}} to restrict
2127 the compilers to be built, only those you've actually enabled will be
2128 built. This will of course only build those runtime libraries, for
2129 which the particular compiler has been built. Please note,
2130 that re-defining @env{LANGUAGES} when calling @samp{make}
2131 @strong{does not} work anymore!
2132
2133 If the comparison of stage2 and stage3 fails, this normally indicates
2134 that the stage2 compiler has compiled GCC incorrectly, and is therefore
2135 a potentially serious bug which you should investigate and report. (On
2136 a few systems, meaningful comparison of object files is impossible; they
2137 always appear ``different''. If you encounter this problem, you will
2138 need to disable comparison in the @file{Makefile}.)
2139
2140 If you do not want to bootstrap your compiler, you can configure with
2141 @option{--disable-bootstrap}. In particular cases, you may want to
2142 bootstrap your compiler even if the target system is not the same as
2143 the one you are building on: for example, you could build a
2144 @code{powerpc-unknown-linux-gnu} toolchain on a
2145 @code{powerpc64-unknown-linux-gnu} host. In this case, pass
2146 @option{--enable-bootstrap} to the configure script.
2147
2148 @code{BUILD_CONFIG} can be used to bring in additional customization
2149 to the build. It can be set to a whitespace-separated list of names.
2150 For each such @code{NAME}, top-level @file{config/@code{NAME}.mk} will
2151 be included by the top-level @file{Makefile}, bringing in any settings
2152 it contains. The default @code{BUILD_CONFIG} can be set using the
2153 configure option @option{--with-build-config=@code{NAME}...}. Some
2154 examples of supported build configurations are:
2155
2156 @table @asis
2157 @item @samp{bootstrap-O1}
2158 Removes any @option{-O}-started option from @code{BOOT_CFLAGS}, and adds
2159 @option{-O1} to it. @samp{BUILD_CONFIG=bootstrap-O1} is equivalent to
2160 @samp{BOOT_CFLAGS='-g -O1'}.
2161
2162 @item @samp{bootstrap-O3}
2163 Analogous to @code{bootstrap-O1}.
2164
2165 @item @samp{bootstrap-lto}
2166 Enables Link-Time Optimization for host tools during bootstrapping.
2167 @samp{BUILD_CONFIG=bootstrap-lto} is equivalent to adding
2168 @option{-flto} to @samp{BOOT_CFLAGS}.
2169
2170 @item @samp{bootstrap-debug}
2171 Verifies that the compiler generates the same executable code, whether
2172 or not it is asked to emit debug information. To this end, this
2173 option builds stage2 host programs without debug information, and uses
2174 @file{contrib/compare-debug} to compare them with the stripped stage3
2175 object files. If @code{BOOT_CFLAGS} is overridden so as to not enable
2176 debug information, stage2 will have it, and stage3 won't. This option
2177 is enabled by default when GCC bootstrapping is enabled, if
2178 @code{strip} can turn object files compiled with and without debug
2179 info into identical object files. In addition to better test
2180 coverage, this option makes default bootstraps faster and leaner.
2181
2182 @item @samp{bootstrap-debug-big}
2183 Rather than comparing stripped object files, as in
2184 @code{bootstrap-debug}, this option saves internal compiler dumps
2185 during stage2 and stage3 and compares them as well, which helps catch
2186 additional potential problems, but at a great cost in terms of disk
2187 space. It can be specified in addition to @samp{bootstrap-debug}.
2188
2189 @item @samp{bootstrap-debug-lean}
2190 This option saves disk space compared with @code{bootstrap-debug-big},
2191 but at the expense of some recompilation. Instead of saving the dumps
2192 of stage2 and stage3 until the final compare, it uses
2193 @option{-fcompare-debug} to generate, compare and remove the dumps
2194 during stage3, repeating the compilation that already took place in
2195 stage2, whose dumps were not saved.
2196
2197 @item @samp{bootstrap-debug-lib}
2198 This option tests executable code invariance over debug information
2199 generation on target libraries, just like @code{bootstrap-debug-lean}
2200 tests it on host programs. It builds stage3 libraries with
2201 @option{-fcompare-debug}, and it can be used along with any of the
2202 @code{bootstrap-debug} options above.
2203
2204 There aren't @code{-lean} or @code{-big} counterparts to this option
2205 because most libraries are only build in stage3, so bootstrap compares
2206 would not get significant coverage. Moreover, the few libraries built
2207 in stage2 are used in stage3 host programs, so we wouldn't want to
2208 compile stage2 libraries with different options for comparison purposes.
2209
2210 @item @samp{bootstrap-debug-ckovw}
2211 Arranges for error messages to be issued if the compiler built on any
2212 stage is run without the option @option{-fcompare-debug}. This is
2213 useful to verify the full @option{-fcompare-debug} testing coverage. It
2214 must be used along with @code{bootstrap-debug-lean} and
2215 @code{bootstrap-debug-lib}.
2216
2217 @item @samp{bootstrap-time}
2218 Arranges for the run time of each program started by the GCC driver,
2219 built in any stage, to be logged to @file{time.log}, in the top level of
2220 the build tree.
2221
2222 @end table
2223
2224 @section Building a cross compiler
2225
2226 When building a cross compiler, it is not generally possible to do a
2227 3-stage bootstrap of the compiler. This makes for an interesting problem
2228 as parts of GCC can only be built with GCC@.
2229
2230 To build a cross compiler, we recommend first building and installing a
2231 native compiler. You can then use the native GCC compiler to build the
2232 cross compiler. The installed native compiler needs to be GCC version
2233 2.95 or later.
2234
2235 If the cross compiler is to be built with support for the Java
2236 programming language and the ability to compile .java source files is
2237 desired, the installed native compiler used to build the cross
2238 compiler needs to be the same GCC version as the cross compiler. In
2239 addition the cross compiler needs to be configured with
2240 @option{--with-ecj-jar=@dots{}}.
2241
2242 Assuming you have already installed a native copy of GCC and configured
2243 your cross compiler, issue the command @command{make}, which performs the
2244 following steps:
2245
2246 @itemize @bullet
2247 @item
2248 Build host tools necessary to build the compiler.
2249
2250 @item
2251 Build target tools for use by the compiler such as binutils (bfd,
2252 binutils, gas, gprof, ld, and opcodes)
2253 if they have been individually linked or moved into the top level GCC source
2254 tree before configuring.
2255
2256 @item
2257 Build the compiler (single stage only).
2258
2259 @item
2260 Build runtime libraries using the compiler from the previous step.
2261 @end itemize
2262
2263 Note that if an error occurs in any step the make process will exit.
2264
2265 If you are not building GNU binutils in the same source tree as GCC,
2266 you will need a cross-assembler and cross-linker installed before
2267 configuring GCC@. Put them in the directory
2268 @file{@var{prefix}/@var{target}/bin}. Here is a table of the tools
2269 you should put in this directory:
2270
2271 @table @file
2272 @item as
2273 This should be the cross-assembler.
2274
2275 @item ld
2276 This should be the cross-linker.
2277
2278 @item ar
2279 This should be the cross-archiver: a program which can manipulate
2280 archive files (linker libraries) in the target machine's format.
2281
2282 @item ranlib
2283 This should be a program to construct a symbol table in an archive file.
2284 @end table
2285
2286 The installation of GCC will find these programs in that directory,
2287 and copy or link them to the proper place to for the cross-compiler to
2288 find them when run later.
2289
2290 The easiest way to provide these files is to build the Binutils package.
2291 Configure it with the same @option{--host} and @option{--target}
2292 options that you use for configuring GCC, then build and install
2293 them. They install their executables automatically into the proper
2294 directory. Alas, they do not support all the targets that GCC
2295 supports.
2296
2297 If you are not building a C library in the same source tree as GCC,
2298 you should also provide the target libraries and headers before
2299 configuring GCC, specifying the directories with
2300 @option{--with-sysroot} or @option{--with-headers} and
2301 @option{--with-libs}. Many targets also require ``start files'' such
2302 as @file{crt0.o} and
2303 @file{crtn.o} which are linked into each executable. There may be several
2304 alternatives for @file{crt0.o}, for use with profiling or other
2305 compilation options. Check your target's definition of
2306 @code{STARTFILE_SPEC} to find out what start files it uses.
2307
2308 @section Building in parallel
2309
2310 GNU Make 3.80 and above, which is necessary to build GCC, support
2311 building in parallel. To activate this, you can use @samp{make -j 2}
2312 instead of @samp{make}. You can also specify a bigger number, and
2313 in most cases using a value greater than the number of processors in
2314 your machine will result in fewer and shorter I/O latency hits, thus
2315 improving overall throughput; this is especially true for slow drives
2316 and network filesystems.
2317
2318 @section Building the Ada compiler
2319
2320 In order to build GNAT, the Ada compiler, you need a working GNAT
2321 compiler (GCC version 4.0 or later).
2322 This includes GNAT tools such as @command{gnatmake} and
2323 @command{gnatlink}, since the Ada front end is written in Ada and
2324 uses some GNAT-specific extensions.
2325
2326 In order to build a cross compiler, it is suggested to install
2327 the new compiler as native first, and then use it to build the cross
2328 compiler.
2329
2330 @command{configure} does not test whether the GNAT installation works
2331 and has a sufficiently recent version; if too old a GNAT version is
2332 installed, the build will fail unless @option{--enable-languages} is
2333 used to disable building the Ada front end.
2334
2335 @env{ADA_INCLUDE_PATH} and @env{ADA_OBJECT_PATH} environment variables
2336 must not be set when building the Ada compiler, the Ada tools, or the
2337 Ada runtime libraries. You can check that your build environment is clean
2338 by verifying that @samp{gnatls -v} lists only one explicit path in each
2339 section.
2340
2341 @section Building with profile feedback
2342
2343 It is possible to use profile feedback to optimize the compiler itself. This
2344 should result in a faster compiler binary. Experiments done on x86 using gcc
2345 3.3 showed approximately 7 percent speedup on compiling C programs. To
2346 bootstrap the compiler with profile feedback, use @code{make profiledbootstrap}.
2347
2348 When @samp{make profiledbootstrap} is run, it will first build a @code{stage1}
2349 compiler. This compiler is used to build a @code{stageprofile} compiler
2350 instrumented to collect execution counts of instruction and branch
2351 probabilities. Then runtime libraries are compiled with profile collected.
2352 Finally a @code{stagefeedback} compiler is built using the information collected.
2353
2354 Unlike standard bootstrap, several additional restrictions apply. The
2355 compiler used to build @code{stage1} needs to support a 64-bit integral type.
2356 It is recommended to only use GCC for this. Also parallel make is currently
2357 not supported since collisions in profile collecting may occur.
2358
2359 @html
2360 <hr />
2361 <p>
2362 @end html
2363 @ifhtml
2364 @uref{./index.html,,Return to the GCC Installation page}
2365 @end ifhtml
2366 @end ifset
2367
2368 @c ***Testing*****************************************************************
2369 @ifnothtml
2370 @comment node-name, next, previous, up
2371 @node Testing, Final install, Building, Installing GCC
2372 @end ifnothtml
2373 @ifset testhtml
2374 @ifnothtml
2375 @chapter Installing GCC: Testing
2376 @end ifnothtml
2377 @cindex Testing
2378 @cindex Installing GCC: Testing
2379 @cindex Testsuite
2380
2381 Before you install GCC, we encourage you to run the testsuites and to
2382 compare your results with results from a similar configuration that have
2383 been submitted to the
2384 @uref{http://gcc.gnu.org/ml/gcc-testresults/,,gcc-testresults mailing list}.
2385 Some of these archived results are linked from the build status lists
2386 at @uref{http://gcc.gnu.org/buildstat.html}, although not everyone who
2387 reports a successful build runs the testsuites and submits the results.
2388 This step is optional and may require you to download additional software,
2389 but it can give you confidence in your new GCC installation or point out
2390 problems before you install and start using your new GCC@.
2391
2392 First, you must have @uref{download.html,,downloaded the testsuites}.
2393 These are part of the full distribution, but if you downloaded the
2394 ``core'' compiler plus any front ends, you must download the testsuites
2395 separately.
2396
2397 Second, you must have the testing tools installed. This includes
2398 @uref{http://www.gnu.org/software/dejagnu/,,DejaGnu}, Tcl, and Expect;
2399 the DejaGnu site has links to these.
2400
2401 If the directories where @command{runtest} and @command{expect} were
2402 installed are not in the @env{PATH}, you may need to set the following
2403 environment variables appropriately, as in the following example (which
2404 assumes that DejaGnu has been installed under @file{/usr/local}):
2405
2406 @smallexample
2407 TCL_LIBRARY = /usr/local/share/tcl8.0
2408 DEJAGNULIBS = /usr/local/share/dejagnu
2409 @end smallexample
2410
2411 (On systems such as Cygwin, these paths are required to be actual
2412 paths, not mounts or links; presumably this is due to some lack of
2413 portability in the DejaGnu code.)
2414
2415
2416 Finally, you can run the testsuite (which may take a long time):
2417 @smallexample
2418 cd @var{objdir}; make -k check
2419 @end smallexample
2420
2421 This will test various components of GCC, such as compiler
2422 front ends and runtime libraries. While running the testsuite, DejaGnu
2423 might emit some harmless messages resembling
2424 @samp{WARNING: Couldn't find the global config file.} or
2425 @samp{WARNING: Couldn't find tool init file} that can be ignored.
2426
2427 If you are testing a cross-compiler, you may want to run the testsuite
2428 on a simulator as described at @uref{http://gcc.gnu.org/simtest-howto.html}.
2429
2430 @section How can you run the testsuite on selected tests?
2431
2432 In order to run sets of tests selectively, there are targets
2433 @samp{make check-gcc} and @samp{make check-g++}
2434 in the @file{gcc} subdirectory of the object directory. You can also
2435 just run @samp{make check} in a subdirectory of the object directory.
2436
2437
2438 A more selective way to just run all @command{gcc} execute tests in the
2439 testsuite is to use
2440
2441 @smallexample
2442 make check-gcc RUNTESTFLAGS="execute.exp @var{other-options}"
2443 @end smallexample
2444
2445 Likewise, in order to run only the @command{g++} ``old-deja'' tests in
2446 the testsuite with filenames matching @samp{9805*}, you would use
2447
2448 @smallexample
2449 make check-g++ RUNTESTFLAGS="old-deja.exp=9805* @var{other-options}"
2450 @end smallexample
2451
2452 The @file{*.exp} files are located in the testsuite directories of the GCC
2453 source, the most important ones being @file{compile.exp},
2454 @file{execute.exp}, @file{dg.exp} and @file{old-deja.exp}.
2455 To get a list of the possible @file{*.exp} files, pipe the
2456 output of @samp{make check} into a file and look at the
2457 @samp{Running @dots{} .exp} lines.
2458
2459 @section Passing options and running multiple testsuites
2460
2461 You can pass multiple options to the testsuite using the
2462 @samp{--target_board} option of DejaGNU, either passed as part of
2463 @samp{RUNTESTFLAGS}, or directly to @command{runtest} if you prefer to
2464 work outside the makefiles. For example,
2465
2466 @smallexample
2467 make check-g++ RUNTESTFLAGS="--target_board=unix/-O3/-fmerge-constants"
2468 @end smallexample
2469
2470 will run the standard @command{g++} testsuites (``unix'' is the target name
2471 for a standard native testsuite situation), passing
2472 @samp{-O3 -fmerge-constants} to the compiler on every test, i.e.,
2473 slashes separate options.
2474
2475 You can run the testsuites multiple times using combinations of options
2476 with a syntax similar to the brace expansion of popular shells:
2477
2478 @smallexample
2479 @dots{}"--target_board=arm-sim\@{-mhard-float,-msoft-float\@}\@{-O1,-O2,-O3,\@}"
2480 @end smallexample
2481
2482 (Note the empty option caused by the trailing comma in the final group.)
2483 The following will run each testsuite eight times using the @samp{arm-sim}
2484 target, as if you had specified all possible combinations yourself:
2485
2486 @smallexample
2487 --target_board=arm-sim/-mhard-float/-O1
2488 --target_board=arm-sim/-mhard-float/-O2
2489 --target_board=arm-sim/-mhard-float/-O3
2490 --target_board=arm-sim/-mhard-float
2491 --target_board=arm-sim/-msoft-float/-O1
2492 --target_board=arm-sim/-msoft-float/-O2
2493 --target_board=arm-sim/-msoft-float/-O3
2494 --target_board=arm-sim/-msoft-float
2495 @end smallexample
2496
2497 They can be combined as many times as you wish, in arbitrary ways. This
2498 list:
2499
2500 @smallexample
2501 @dots{}"--target_board=unix/-Wextra\@{-O3,-fno-strength\@}\@{-fomit-frame,\@}"
2502 @end smallexample
2503
2504 will generate four combinations, all involving @samp{-Wextra}.
2505
2506 The disadvantage to this method is that the testsuites are run in serial,
2507 which is a waste on multiprocessor systems. For users with GNU Make and
2508 a shell which performs brace expansion, you can run the testsuites in
2509 parallel by having the shell perform the combinations and @command{make}
2510 do the parallel runs. Instead of using @samp{--target_board}, use a
2511 special makefile target:
2512
2513 @smallexample
2514 make -j@var{N} check-@var{testsuite}//@var{test-target}/@var{option1}/@var{option2}/@dots{}
2515 @end smallexample
2516
2517 For example,
2518
2519 @smallexample
2520 make -j3 check-gcc//sh-hms-sim/@{-m1,-m2,-m3,-m3e,-m4@}/@{,-nofpu@}
2521 @end smallexample
2522
2523 will run three concurrent ``make-gcc'' testsuites, eventually testing all
2524 ten combinations as described above. Note that this is currently only
2525 supported in the @file{gcc} subdirectory. (To see how this works, try
2526 typing @command{echo} before the example given here.)
2527
2528
2529 @section Additional testing for Java Class Libraries
2530
2531 The Java runtime tests can be executed via @samp{make check}
2532 in the @file{@var{target}/libjava/testsuite} directory in
2533 the build tree.
2534
2535 The @uref{http://sourceware.org/mauve/,,Mauve Project} provides
2536 a suite of tests for the Java Class Libraries. This suite can be run
2537 as part of libgcj testing by placing the Mauve tree within the libjava
2538 testsuite at @file{libjava/testsuite/libjava.mauve/mauve}, or by
2539 specifying the location of that tree when invoking @samp{make}, as in
2540 @samp{make MAUVEDIR=~/mauve check}.
2541
2542 @section How to interpret test results
2543
2544 The result of running the testsuite are various @file{*.sum} and @file{*.log}
2545 files in the testsuite subdirectories. The @file{*.log} files contain a
2546 detailed log of the compiler invocations and the corresponding
2547 results, the @file{*.sum} files summarize the results. These summaries
2548 contain status codes for all tests:
2549
2550 @itemize @bullet
2551 @item
2552 PASS: the test passed as expected
2553 @item
2554 XPASS: the test unexpectedly passed
2555 @item
2556 FAIL: the test unexpectedly failed
2557 @item
2558 XFAIL: the test failed as expected
2559 @item
2560 UNSUPPORTED: the test is not supported on this platform
2561 @item
2562 ERROR: the testsuite detected an error
2563 @item
2564 WARNING: the testsuite detected a possible problem
2565 @end itemize
2566
2567 It is normal for some tests to report unexpected failures. At the
2568 current time the testing harness does not allow fine grained control
2569 over whether or not a test is expected to fail. This problem should
2570 be fixed in future releases.
2571
2572
2573 @section Submitting test results
2574
2575 If you want to report the results to the GCC project, use the
2576 @file{contrib/test_summary} shell script. Start it in the @var{objdir} with
2577
2578 @smallexample
2579 @var{srcdir}/contrib/test_summary -p your_commentary.txt \
2580 -m gcc-testresults@@gcc.gnu.org |sh
2581 @end smallexample
2582
2583 This script uses the @command{Mail} program to send the results, so
2584 make sure it is in your @env{PATH}. The file @file{your_commentary.txt} is
2585 prepended to the testsuite summary and should contain any special
2586 remarks you have on your results or your build environment. Please
2587 do not edit the testsuite result block or the subject line, as these
2588 messages may be automatically processed.
2589
2590 @html
2591 <hr />
2592 <p>
2593 @end html
2594 @ifhtml
2595 @uref{./index.html,,Return to the GCC Installation page}
2596 @end ifhtml
2597 @end ifset
2598
2599 @c ***Final install***********************************************************
2600 @ifnothtml
2601 @comment node-name, next, previous, up
2602 @node Final install, , Testing, Installing GCC
2603 @end ifnothtml
2604 @ifset finalinstallhtml
2605 @ifnothtml
2606 @chapter Installing GCC: Final installation
2607 @end ifnothtml
2608
2609 Now that GCC has been built (and optionally tested), you can install it with
2610 @smallexample
2611 cd @var{objdir}; make install
2612 @end smallexample
2613
2614 We strongly recommend to install into a target directory where there is
2615 no previous version of GCC present. Also, the GNAT runtime should not
2616 be stripped, as this would break certain features of the debugger that
2617 depend on this debugging information (catching Ada exceptions for
2618 instance).
2619
2620 That step completes the installation of GCC; user level binaries can
2621 be found in @file{@var{prefix}/bin} where @var{prefix} is the value
2622 you specified with the @option{--prefix} to configure (or
2623 @file{/usr/local} by default). (If you specified @option{--bindir},
2624 that directory will be used instead; otherwise, if you specified
2625 @option{--exec-prefix}, @file{@var{exec-prefix}/bin} will be used.)
2626 Headers for the C++ and Java libraries are installed in
2627 @file{@var{prefix}/include}; libraries in @file{@var{libdir}}
2628 (normally @file{@var{prefix}/lib}); internal parts of the compiler in
2629 @file{@var{libdir}/gcc} and @file{@var{libexecdir}/gcc}; documentation
2630 in info format in @file{@var{infodir}} (normally
2631 @file{@var{prefix}/info}).
2632
2633 When installing cross-compilers, GCC's executables
2634 are not only installed into @file{@var{bindir}}, that
2635 is, @file{@var{exec-prefix}/bin}, but additionally into
2636 @file{@var{exec-prefix}/@var{target-alias}/bin}, if that directory
2637 exists. Typically, such @dfn{tooldirs} hold target-specific
2638 binutils, including assembler and linker.
2639
2640 Installation into a temporary staging area or into a @command{chroot}
2641 jail can be achieved with the command
2642
2643 @smallexample
2644 make DESTDIR=@var{path-to-rootdir} install
2645 @end smallexample
2646
2647 @noindent where @var{path-to-rootdir} is the absolute path of
2648 a directory relative to which all installation paths will be
2649 interpreted. Note that the directory specified by @code{DESTDIR}
2650 need not exist yet; it will be created if necessary.
2651
2652 There is a subtle point with tooldirs and @code{DESTDIR}:
2653 If you relocate a cross-compiler installation with
2654 e.g.@: @samp{DESTDIR=@var{rootdir}}, then the directory
2655 @file{@var{rootdir}/@var{exec-prefix}/@var{target-alias}/bin} will
2656 be filled with duplicated GCC executables only if it already exists,
2657 it will not be created otherwise. This is regarded as a feature,
2658 not as a bug, because it gives slightly more control to the packagers
2659 using the @code{DESTDIR} feature.
2660
2661 If you are bootstrapping a released version of GCC then please
2662 quickly review the build status page for your release, available from
2663 @uref{http://gcc.gnu.org/buildstat.html}.
2664 If your system is not listed for the version of GCC that you built,
2665 send a note to
2666 @email{gcc@@gcc.gnu.org} indicating
2667 that you successfully built and installed GCC@.
2668 Include the following information:
2669
2670 @itemize @bullet
2671 @item
2672 Output from running @file{@var{srcdir}/config.guess}. Do not send
2673 that file itself, just the one-line output from running it.
2674
2675 @item
2676 The output of @samp{gcc -v} for your newly installed @command{gcc}.
2677 This tells us which version of GCC you built and the options you passed to
2678 configure.
2679
2680 @item
2681 Whether you enabled all languages or a subset of them. If you used a
2682 full distribution then this information is part of the configure
2683 options in the output of @samp{gcc -v}, but if you downloaded the
2684 ``core'' compiler plus additional front ends then it isn't apparent
2685 which ones you built unless you tell us about it.
2686
2687 @item
2688 If the build was for GNU/Linux, also include:
2689 @itemize @bullet
2690 @item
2691 The distribution name and version (e.g., Red Hat 7.1 or Debian 2.2.3);
2692 this information should be available from @file{/etc/issue}.
2693
2694 @item
2695 The version of the Linux kernel, available from @samp{uname --version}
2696 or @samp{uname -a}.
2697
2698 @item
2699 The version of glibc you used; for RPM-based systems like Red Hat,
2700 Mandrake, and SuSE type @samp{rpm -q glibc} to get the glibc version,
2701 and on systems like Debian and Progeny use @samp{dpkg -l libc6}.
2702 @end itemize
2703 For other systems, you can include similar information if you think it is
2704 relevant.
2705
2706 @item
2707 Any other information that you think would be useful to people building
2708 GCC on the same configuration. The new entry in the build status list
2709 will include a link to the archived copy of your message.
2710 @end itemize
2711
2712 We'd also like to know if the
2713 @ifnothtml
2714 @ref{Specific, host/target specific installation notes}
2715 @end ifnothtml
2716 @ifhtml
2717 @uref{specific.html,,host/target specific installation notes}
2718 @end ifhtml
2719 didn't include your host/target information or if that information is
2720 incomplete or out of date. Send a note to
2721 @email{gcc@@gcc.gnu.org} detailing how the information should be changed.
2722
2723 If you find a bug, please report it following the
2724 @uref{../bugs/,,bug reporting guidelines}.
2725
2726 If you want to print the GCC manuals, do @samp{cd @var{objdir}; make
2727 dvi}. You will need to have @command{texi2dvi} (version at least 4.7)
2728 and @TeX{} installed. This creates a number of @file{.dvi} files in
2729 subdirectories of @file{@var{objdir}}; these may be converted for
2730 printing with programs such as @command{dvips}. Alternately, by using
2731 @samp{make pdf} in place of @samp{make dvi}, you can create documentation
2732 in the form of @file{.pdf} files; this requires @command{texi2pdf}, which
2733 is included with Texinfo version 4.8 and later. You can also
2734 @uref{http://shop.fsf.org/,,buy printed manuals from the
2735 Free Software Foundation}, though such manuals may not be for the most
2736 recent version of GCC@.
2737
2738 If you would like to generate online HTML documentation, do @samp{cd
2739 @var{objdir}; make html} and HTML will be generated for the gcc manuals in
2740 @file{@var{objdir}/gcc/HTML}.
2741
2742 @html
2743 <hr />
2744 <p>
2745 @end html
2746 @ifhtml
2747 @uref{./index.html,,Return to the GCC Installation page}
2748 @end ifhtml
2749 @end ifset
2750
2751 @c ***Binaries****************************************************************
2752 @ifnothtml
2753 @comment node-name, next, previous, up
2754 @node Binaries, Specific, Installing GCC, Top
2755 @end ifnothtml
2756 @ifset binarieshtml
2757 @ifnothtml
2758 @chapter Installing GCC: Binaries
2759 @end ifnothtml
2760 @cindex Binaries
2761 @cindex Installing GCC: Binaries
2762
2763 We are often asked about pre-compiled versions of GCC@. While we cannot
2764 provide these for all platforms, below you'll find links to binaries for
2765 various platforms where creating them by yourself is not easy due to various
2766 reasons.
2767
2768 Please note that we did not create these binaries, nor do we
2769 support them. If you have any problems installing them, please
2770 contact their makers.
2771
2772 @itemize
2773 @item
2774 AIX:
2775 @itemize
2776 @item
2777 @uref{http://www.bullfreeware.com,,Bull's Freeware and Shareware Archive for AIX};
2778
2779 @item
2780 @uref{http://pware.hvcc.edu,,Hudson Valley Community College Open Source Software for IBM System p};
2781
2782 @item
2783 @uref{http://www.perzl.org/aix/,,AIX 5L and 6 Open Source Packages}.
2784 @end itemize
2785
2786 @item
2787 DOS---@uref{http://www.delorie.com/djgpp/,,DJGPP}.
2788
2789 @item
2790 Renesas H8/300[HS]---@uref{http://h8300-hms.sourceforge.net/,,GNU
2791 Development Tools for the Renesas H8/300[HS] Series}.
2792
2793 @item
2794 HP-UX:
2795 @itemize
2796 @item
2797 @uref{http://hpux.connect.org.uk/,,HP-UX Porting Center};
2798
2799 @item
2800 @uref{ftp://sunsite.informatik.rwth-aachen.de/pub/packages/gcc_hpux/,,Binaries for HP-UX 11.00 at Aachen University of Technology}.
2801 @end itemize
2802
2803 @item
2804 Motorola 68HC11/68HC12---@uref{http://www.gnu-m68hc11.org,,GNU
2805 Development Tools for the Motorola 68HC11/68HC12}.
2806
2807 @item
2808 @uref{http://www.sco.com/skunkware/devtools/index.html#gcc,,SCO
2809 OpenServer/Unixware}.
2810
2811 @item
2812 Solaris 2 (SPARC, Intel):
2813 @itemize
2814 @item
2815 @uref{http://www.sunfreeware.com/,,Sunfreeware}
2816
2817 @item
2818 @uref{http://www.blastwave.org/,,Blastwave}
2819
2820 @item
2821 @uref{http://www.opencsw.org/,,OpenCSW}
2822
2823 @item
2824 @uref{http://jupiterrise.com/tgcware/,,TGCware}
2825 @end itemize
2826
2827 @item
2828 SGI IRIX:
2829 @itemize
2830 @item
2831 @uref{http://nekochan.net/,,Nekoware}
2832
2833 @item
2834 @uref{http://jupiterrise.com/tgcware/,,TGCware}
2835 @end itemize
2836
2837 @item
2838 Microsoft Windows:
2839 @itemize
2840 @item
2841 The @uref{http://sourceware.org/cygwin/,,Cygwin} project;
2842 @item
2843 The @uref{http://www.mingw.org/,,MinGW} project.
2844 @end itemize
2845
2846 @item
2847 @uref{ftp://ftp.thewrittenword.com/packages/by-name/,,The
2848 Written Word} offers binaries for
2849 AIX 4.3.3, 5.1 and 5.2,
2850 IRIX 6.5,
2851 Tru64 UNIX 4.0D and 5.1,
2852 GNU/Linux (i386),
2853 HP-UX 10.20, 11.00, and 11.11, and
2854 Solaris/SPARC 2.5.1, 2.6, 7, 8, 9 and 10.
2855
2856 @item
2857 @uref{http://www.openpkg.org/,,OpenPKG} offers binaries for quite a
2858 number of platforms.
2859
2860 @item
2861 The @uref{http://gcc.gnu.org/wiki/GFortranBinaries,,GFortran Wiki} has
2862 links to GNU Fortran binaries for several platforms.
2863 @end itemize
2864
2865 @html
2866 <hr />
2867 <p>
2868 @end html
2869 @ifhtml
2870 @uref{./index.html,,Return to the GCC Installation page}
2871 @end ifhtml
2872 @end ifset
2873
2874 @c ***Specific****************************************************************
2875 @ifnothtml
2876 @comment node-name, next, previous, up
2877 @node Specific, Old, Binaries, Top
2878 @end ifnothtml
2879 @ifset specifichtml
2880 @ifnothtml
2881 @chapter Host/target specific installation notes for GCC
2882 @end ifnothtml
2883 @cindex Specific
2884 @cindex Specific installation notes
2885 @cindex Target specific installation
2886 @cindex Host specific installation
2887 @cindex Target specific installation notes
2888
2889 Please read this document carefully @emph{before} installing the
2890 GNU Compiler Collection on your machine.
2891
2892 Note that this list of install notes is @emph{not} a list of supported
2893 hosts or targets. Not all supported hosts and targets are listed
2894 here, only the ones that require host-specific or target-specific
2895 information are.
2896
2897 @ifhtml
2898 @itemize
2899 @item
2900 @uref{#alpha-x-x,,alpha*-*-*}
2901 @item
2902 @uref{#alpha-dec-osf51,,alpha*-dec-osf5.1}
2903 @item
2904 @uref{#arc-x-elf,,arc-*-elf}
2905 @item
2906 @uref{#arm-x-elf,,arm-*-elf}
2907 @item
2908 @uref{#avr,,avr}
2909 @item
2910 @uref{#bfin,,Blackfin}
2911 @item
2912 @uref{#dos,,DOS}
2913 @item
2914 @uref{#x-x-freebsd,,*-*-freebsd*}
2915 @item
2916 @uref{#h8300-hms,,h8300-hms}
2917 @item
2918 @uref{#hppa-hp-hpux,,hppa*-hp-hpux*}
2919 @item
2920 @uref{#hppa-hp-hpux10,,hppa*-hp-hpux10}
2921 @item
2922 @uref{#hppa-hp-hpux11,,hppa*-hp-hpux11}
2923 @item
2924 @uref{#x-x-linux-gnu,,*-*-linux-gnu}
2925 @item
2926 @uref{#ix86-x-linux,,i?86-*-linux*}
2927 @item
2928 @uref{#ix86-x-solaris289,,i?86-*-solaris2.[89]}
2929 @item
2930 @uref{#ix86-x-solaris210,,i?86-*-solaris2.10}
2931 @item
2932 @uref{#ia64-x-linux,,ia64-*-linux}
2933 @item
2934 @uref{#ia64-x-hpux,,ia64-*-hpux*}
2935 @item
2936 @uref{#x-ibm-aix,,*-ibm-aix*}
2937 @item
2938 @uref{#iq2000-x-elf,,iq2000-*-elf}
2939 @item
2940 @uref{#lm32-x-elf,,lm32-*-elf}
2941 @item
2942 @uref{#lm32-x-uclinux,,lm32-*-uclinux}
2943 @item
2944 @uref{#m32c-x-elf,,m32c-*-elf}
2945 @item
2946 @uref{#m32r-x-elf,,m32r-*-elf}
2947 @item
2948 @uref{#m6811-elf,,m6811-elf}
2949 @item
2950 @uref{#m6812-elf,,m6812-elf}
2951 @item
2952 @uref{#m68k-x-x,,m68k-*-*}
2953 @item
2954 @uref{#m68k-uclinux,,m68k-uclinux}
2955 @item
2956 @uref{#mep-x-elf,,mep-*-elf}
2957 @item
2958 @uref{#microblaze-x-elf,,microblaze-*-elf}
2959 @item
2960 @uref{#mips-x-x,,mips-*-*}
2961 @item
2962 @uref{#mips-sgi-irix5,,mips-sgi-irix5}
2963 @item
2964 @uref{#mips-sgi-irix6,,mips-sgi-irix6}
2965 @item
2966 @uref{#powerpc-x-x,,powerpc*-*-*}
2967 @item
2968 @uref{#powerpc-x-darwin,,powerpc-*-darwin*}
2969 @item
2970 @uref{#powerpc-x-elf,,powerpc-*-elf}
2971 @item
2972 @uref{#powerpc-x-linux-gnu,,powerpc*-*-linux-gnu*}
2973 @item
2974 @uref{#powerpc-x-netbsd,,powerpc-*-netbsd*}
2975 @item
2976 @uref{#powerpc-x-eabisim,,powerpc-*-eabisim}
2977 @item
2978 @uref{#powerpc-x-eabi,,powerpc-*-eabi}
2979 @item
2980 @uref{#powerpcle-x-elf,,powerpcle-*-elf}
2981 @item
2982 @uref{#powerpcle-x-eabisim,,powerpcle-*-eabisim}
2983 @item
2984 @uref{#powerpcle-x-eabi,,powerpcle-*-eabi}
2985 @item
2986 @uref{#s390-x-linux,,s390-*-linux*}
2987 @item
2988 @uref{#s390x-x-linux,,s390x-*-linux*}
2989 @item
2990 @uref{#s390x-ibm-tpf,,s390x-ibm-tpf*}
2991 @item
2992 @uref{#x-x-solaris2,,*-*-solaris2*}
2993 @item
2994 @uref{#sparc-x-x,,sparc*-*-*}
2995 @item
2996 @uref{#sparc-sun-solaris2,,sparc-sun-solaris2*}
2997 @item
2998 @uref{#sparc-sun-solaris210,,sparc-sun-solaris2.10}
2999 @item
3000 @uref{#sparc-x-linux,,sparc-*-linux*}
3001 @item
3002 @uref{#sparc64-x-solaris2,,sparc64-*-solaris2*}
3003 @item
3004 @uref{#sparcv9-x-solaris2,,sparcv9-*-solaris2*}
3005 @item
3006 @uref{#x-x-vxworks,,*-*-vxworks*}
3007 @item
3008 @uref{#x86-64-x-x,,x86_64-*-*, amd64-*-*}
3009 @item
3010 @uref{#xtensa-x-elf,,xtensa*-*-elf}
3011 @item
3012 @uref{#xtensa-x-linux,,xtensa*-*-linux*}
3013 @item
3014 @uref{#windows,,Microsoft Windows}
3015 @item
3016 @uref{#x-x-cygwin,,*-*-cygwin}
3017 @item
3018 @uref{#x-x-interix,,*-*-interix}
3019 @item
3020 @uref{#x-x-mingw32,,*-*-mingw32}
3021 @item
3022 @uref{#os2,,OS/2}
3023 @item
3024 @uref{#older,,Older systems}
3025 @end itemize
3026
3027 @itemize
3028 @item
3029 @uref{#elf,,all ELF targets} (SVR4, Solaris 2, etc.)
3030 @end itemize
3031 @end ifhtml
3032
3033
3034 @html
3035 <!-- -------- host/target specific issues start here ---------------- -->
3036 <hr />
3037 @end html
3038 @heading @anchor{alpha-x-x}alpha*-*-*
3039
3040 This section contains general configuration information for all
3041 alpha-based platforms using ELF (in particular, ignore this section for
3042 DEC OSF/1, Digital UNIX and Tru64 UNIX)@. In addition to reading this
3043 section, please read all other sections that match your target.
3044
3045 We require binutils 2.11.2 or newer.
3046 Previous binutils releases had a number of problems with DWARF 2
3047 debugging information, not the least of which is incorrect linking of
3048 shared libraries.
3049
3050 @html
3051 <hr />
3052 @end html
3053 @heading @anchor{alpha-dec-osf51}alpha*-dec-osf5.1
3054 Systems using processors that implement the DEC Alpha architecture and
3055 are running the DEC/Compaq/HP Unix (DEC OSF/1, Digital UNIX, or Compaq/HP
3056 Tru64 UNIX) operating system, for example the DEC Alpha AXP systems.
3057
3058 As of GCC 3.2, versions before @code{alpha*-dec-osf4} are no longer
3059 supported. (These are the versions which identify themselves as DEC
3060 OSF/1.) As of GCC 4.6, support for Tru64 UNIX V4.0 and V5.0 has been
3061 removed.
3062
3063 On Tru64 UNIX, virtual memory exhausted bootstrap failures
3064 may be fixed by reconfiguring Kernel Virtual Memory and Swap parameters
3065 per the @command{/usr/sbin/sys_check} Tuning Suggestions,
3066 or applying the patch in
3067 @uref{http://gcc.gnu.org/ml/gcc/2002-08/msg00822.html}. Depending on
3068 the OS version used, you need a data segment size between 512 MB and
3069 1 GB, so simply use @command{ulimit -Sd unlimited}.
3070
3071 As of GNU binutils 2.20.1, neither GNU @command{as} nor GNU @command{ld}
3072 are supported on Tru64 UNIX, so you must not configure GCC with
3073 @option{--with-gnu-as} or @option{--with-gnu-ld}.
3074
3075 GCC writes a @samp{.verstamp} directive to the assembler output file
3076 unless it is built as a cross-compiler. It gets the version to use from
3077 the system header file @file{/usr/include/stamp.h}. If you install a
3078 new version of Tru64 UNIX, you should rebuild GCC to pick up the new version
3079 stamp.
3080
3081 GCC now supports both the native (ECOFF) debugging format used by DBX
3082 and GDB and an encapsulated STABS format for use only with GDB@. See the
3083 discussion of the @option{--with-stabs} option of @file{configure} above
3084 for more information on these formats and how to select them.
3085 @c FIXME: does this work at all? If so, perhaps make default.
3086
3087 There is a bug in DEC's assembler that produces incorrect line numbers
3088 for ECOFF format when the @samp{.align} directive is used. To work
3089 around this problem, GCC will not emit such alignment directives
3090 while writing ECOFF format debugging information even if optimization is
3091 being performed. Unfortunately, this has the very undesirable
3092 side-effect that code addresses when @option{-O} is specified are
3093 different depending on whether or not @option{-g} is also specified.
3094
3095 To avoid this behavior, specify @option{-gstabs+} and use GDB instead of
3096 DBX@. DEC is now aware of this problem with the assembler and hopes to
3097 provide a fix shortly.
3098
3099 @c FIXME: still applicable?
3100
3101 @html
3102 <hr />
3103 @end html
3104 @heading @anchor{arc-x-elf}arc-*-elf
3105 Argonaut ARC processor.
3106 This configuration is intended for embedded systems.
3107
3108 @html
3109 <hr />
3110 @end html
3111 @heading @anchor{arm-x-elf}arm-*-elf
3112 ARM-family processors. Subtargets that use the ELF object format
3113 require GNU binutils 2.13 or newer. Such subtargets include:
3114 @code{arm-*-freebsd}, @code{arm-*-netbsdelf}, @code{arm-*-*linux}
3115 and @code{arm-*-rtems}.
3116
3117 @html
3118 <hr />
3119 @end html
3120 @heading @anchor{avr}avr
3121
3122 ATMEL AVR-family micro controllers. These are used in embedded
3123 applications. There are no standard Unix configurations.
3124 @ifnothtml
3125 @xref{AVR Options,, AVR Options, gcc, Using the GNU Compiler
3126 Collection (GCC)},
3127 @end ifnothtml
3128 @ifhtml
3129 See ``AVR Options'' in the main manual
3130 @end ifhtml
3131 for the list of supported MCU types.
3132
3133 Use @samp{configure --target=avr --enable-languages="c"} to configure GCC@.
3134
3135 Further installation notes and other useful information about AVR tools
3136 can also be obtained from:
3137
3138 @itemize @bullet
3139 @item
3140 @uref{http://www.nongnu.org/avr/,,http://www.nongnu.org/avr/}
3141 @item
3142 @uref{http://www.amelek.gda.pl/avr/,,http://www.amelek.gda.pl/avr/}
3143 @end itemize
3144
3145 We @emph{strongly} recommend using binutils 2.13 or newer.
3146
3147 The following error:
3148 @smallexample
3149 Error: register required
3150 @end smallexample
3151
3152 indicates that you should upgrade to a newer version of the binutils.
3153
3154 @html
3155 <hr />
3156 @end html
3157 @heading @anchor{bfin}Blackfin
3158
3159 The Blackfin processor, an Analog Devices DSP.
3160 @ifnothtml
3161 @xref{Blackfin Options,, Blackfin Options, gcc, Using the GNU Compiler
3162 Collection (GCC)},
3163 @end ifnothtml
3164 @ifhtml
3165 See ``Blackfin Options'' in the main manual
3166 @end ifhtml
3167
3168 More information, and a version of binutils with support for this processor,
3169 is available at @uref{http://blackfin.uclinux.org}
3170
3171 @html
3172 <hr />
3173 @end html
3174 @heading @anchor{cris}CRIS
3175
3176 CRIS is the CPU architecture in Axis Communications ETRAX system-on-a-chip
3177 series. These are used in embedded applications.
3178
3179 @ifnothtml
3180 @xref{CRIS Options,, CRIS Options, gcc, Using the GNU Compiler
3181 Collection (GCC)},
3182 @end ifnothtml
3183 @ifhtml
3184 See ``CRIS Options'' in the main manual
3185 @end ifhtml
3186 for a list of CRIS-specific options.
3187
3188 There are a few different CRIS targets:
3189 @table @code
3190 @item cris-axis-elf
3191 Mainly for monolithic embedded systems. Includes a multilib for the
3192 @samp{v10} core used in @samp{ETRAX 100 LX}.
3193 @item cris-axis-linux-gnu
3194 A GNU/Linux port for the CRIS architecture, currently targeting
3195 @samp{ETRAX 100 LX} by default.
3196 @end table
3197
3198 For @code{cris-axis-elf} you need binutils 2.11
3199 or newer. For @code{cris-axis-linux-gnu} you need binutils 2.12 or newer.
3200
3201 Pre-packaged tools can be obtained from
3202 @uref{ftp://ftp.axis.com/pub/axis/tools/cris/compiler-kit/}. More
3203 information about this platform is available at
3204 @uref{http://developer.axis.com/}.
3205
3206 @html
3207 <hr />
3208 @end html
3209 @heading @anchor{crx}CRX
3210
3211 The CRX CompactRISC architecture is a low-power 32-bit architecture with
3212 fast context switching and architectural extensibility features.
3213
3214 @ifnothtml
3215 @xref{CRX Options,, CRX Options, gcc, Using and Porting the GNU Compiler
3216 Collection (GCC)},
3217 @end ifnothtml
3218
3219 @ifhtml
3220 See ``CRX Options'' in the main manual for a list of CRX-specific options.
3221 @end ifhtml
3222
3223 Use @samp{configure --target=crx-elf --enable-languages=c,c++} to configure
3224 GCC@ for building a CRX cross-compiler. The option @samp{--target=crx-elf}
3225 is also used to build the @samp{newlib} C library for CRX.
3226
3227 It is also possible to build libstdc++-v3 for the CRX architecture. This
3228 needs to be done in a separate step with the following configure settings:
3229 @samp{gcc/libstdc++-v3/configure --host=crx-elf --with-newlib
3230 --enable-sjlj-exceptions --enable-cxx-flags='-fexceptions -frtti'}
3231
3232 @html
3233 <hr />
3234 @end html
3235 @heading @anchor{dos}DOS
3236
3237 Please have a look at the @uref{binaries.html,,binaries page}.
3238
3239 You cannot install GCC by itself on MSDOS; it will not compile under
3240 any MSDOS compiler except itself. You need to get the complete
3241 compilation package DJGPP, which includes binaries as well as sources,
3242 and includes all the necessary compilation tools and libraries.
3243
3244 @html
3245 <hr />
3246 @end html
3247 @heading @anchor{x-x-freebsd}*-*-freebsd*
3248
3249 Support for FreeBSD 1 was discontinued in GCC 3.2. Support for
3250 FreeBSD 2 (and any mutant a.out variants of FreeBSD 3) was
3251 discontinued in GCC 4.0.
3252
3253 In order to better utilize FreeBSD base system functionality and match
3254 the configuration of the system compiler, GCC 4.5 and above as well as
3255 GCC 4.4 past 2010-06-20 leverage SSP support in libc (which is present
3256 on FreeBSD 7 or later) and the use of @code{__cxa_atexit} by default
3257 (on FreeBSD 6 or later). The use of @code{dl_iterate_phdr} inside
3258 @file{libgcc_s.so.1} and boehm-gc (on FreeBSD 7 or later) is enabled
3259 by GCC 4.5 and above.
3260
3261 We support FreeBSD using the ELF file format with DWARF 2 debugging
3262 for all CPU architectures. You may use @option{-gstabs} instead of
3263 @option{-g}, if you really want the old debugging format. There are
3264 no known issues with mixing object files and libraries with different
3265 debugging formats. Otherwise, this release of GCC should now match
3266 more of the configuration used in the stock FreeBSD configuration of
3267 GCC@. In particular, @option{--enable-threads} is now configured by
3268 default. However, as a general user, do not attempt to replace the
3269 system compiler with this release. Known to bootstrap and check with
3270 good results on FreeBSD 7.2-STABLE@. In the past, known to bootstrap
3271 and check with good results on FreeBSD 3.0, 3.4, 4.0, 4.2, 4.3, 4.4,
3272 4.5, 4.8, 4.9 and 5-CURRENT@.
3273
3274 The version of binutils installed in @file{/usr/bin} probably works
3275 with this release of GCC@. Bootstrapping against the latest GNU
3276 binutils and/or the version found in @file{/usr/ports/devel/binutils} has
3277 been known to enable additional features and improve overall testsuite
3278 results. However, it is currently known that boehm-gc (which itself
3279 is required for java) may not configure properly on FreeBSD prior to
3280 the FreeBSD 7.0 release with GNU binutils after 2.16.1.
3281
3282 @html
3283 <hr />
3284 @end html
3285 @heading @anchor{h8300-hms}h8300-hms
3286 Renesas H8/300 series of processors.
3287
3288 Please have a look at the @uref{binaries.html,,binaries page}.
3289
3290 The calling convention and structure layout has changed in release 2.6.
3291 All code must be recompiled. The calling convention now passes the
3292 first three arguments in function calls in registers. Structures are no
3293 longer a multiple of 2 bytes.
3294
3295 @html
3296 <hr />
3297 @end html
3298 @heading @anchor{hppa-hp-hpux}hppa*-hp-hpux*
3299 Support for HP-UX version 9 and older was discontinued in GCC 3.4.
3300
3301 We require using gas/binutils on all hppa platforms. Version 2.19 or
3302 later is recommended.
3303
3304 It may be helpful to configure GCC with the
3305 @uref{./configure.html#with-gnu-as,,@option{--with-gnu-as}} and
3306 @option{--with-as=@dots{}} options to ensure that GCC can find GAS@.
3307
3308 The HP assembler should not be used with GCC. It is rarely tested and may
3309 not work. It shouldn't be used with any languages other than C due to its
3310 many limitations.
3311
3312 Specifically, @option{-g} does not work (HP-UX uses a peculiar debugging
3313 format which GCC does not know about). It also inserts timestamps
3314 into each object file it creates, causing the 3-stage comparison test to
3315 fail during a bootstrap. You should be able to continue by saying
3316 @samp{make all-host all-target} after getting the failure from @samp{make}.
3317
3318 Various GCC features are not supported. For example, it does not support weak
3319 symbols or alias definitions. As a result, explicit template instantiations
3320 are required when using C++. This makes it difficult if not impossible to
3321 build many C++ applications.
3322
3323 There are two default scheduling models for instructions. These are
3324 PROCESSOR_7100LC and PROCESSOR_8000. They are selected from the pa-risc
3325 architecture specified for the target machine when configuring.
3326 PROCESSOR_8000 is the default. PROCESSOR_7100LC is selected when
3327 the target is a @samp{hppa1*} machine.
3328
3329 The PROCESSOR_8000 model is not well suited to older processors. Thus,
3330 it is important to completely specify the machine architecture when
3331 configuring if you want a model other than PROCESSOR_8000. The macro
3332 TARGET_SCHED_DEFAULT can be defined in BOOT_CFLAGS if a different
3333 default scheduling model is desired.
3334
3335 As of GCC 4.0, GCC uses the UNIX 95 namespace for HP-UX 10.10
3336 through 11.00, and the UNIX 98 namespace for HP-UX 11.11 and later.
3337 This namespace change might cause problems when bootstrapping with
3338 an earlier version of GCC or the HP compiler as essentially the same
3339 namespace is required for an entire build. This problem can be avoided
3340 in a number of ways. With HP cc, @env{UNIX_STD} can be set to @samp{95}
3341 or @samp{98}. Another way is to add an appropriate set of predefines
3342 to @env{CC}. The description for the @option{munix=} option contains
3343 a list of the predefines used with each standard.
3344
3345 More specific information to @samp{hppa*-hp-hpux*} targets follows.
3346
3347 @html
3348 <hr />
3349 @end html
3350 @heading @anchor{hppa-hp-hpux10}hppa*-hp-hpux10
3351
3352 For hpux10.20, we @emph{highly} recommend you pick up the latest sed patch
3353 @code{PHCO_19798} from HP@. HP has two sites which provide patches free of
3354 charge:
3355
3356 @itemize @bullet
3357 @item
3358 @html
3359 <a href="http://us.itrc.hp.com/service/home/home.do">US, Canada, Asia-Pacific, and
3360 Latin-America</a>
3361 @end html
3362 @ifnothtml
3363 @uref{http://us.itrc.hp.com/service/home/home.do,,} US, Canada, Asia-Pacific,
3364 and Latin-America.
3365 @end ifnothtml
3366 @item
3367 @uref{http://europe.itrc.hp.com/service/home/home.do,,} Europe.
3368 @end itemize
3369
3370 The C++ ABI has changed incompatibly in GCC 4.0. COMDAT subspaces are
3371 used for one-only code and data. This resolves many of the previous
3372 problems in using C++ on this target. However, the ABI is not compatible
3373 with the one implemented under HP-UX 11 using secondary definitions.
3374
3375 @html
3376 <hr />
3377 @end html
3378 @heading @anchor{hppa-hp-hpux11}hppa*-hp-hpux11
3379
3380 GCC 3.0 and up support HP-UX 11. GCC 2.95.x is not supported and cannot
3381 be used to compile GCC 3.0 and up.
3382
3383 The libffi and libjava libraries haven't been ported to 64-bit HP-UX@
3384 and don't build.
3385
3386 Refer to @uref{binaries.html,,binaries} for information about obtaining
3387 precompiled GCC binaries for HP-UX@. Precompiled binaries must be obtained
3388 to build the Ada language as it can't be bootstrapped using C@. Ada is
3389 only available for the 32-bit PA-RISC runtime.
3390
3391 Starting with GCC 3.4 an ISO C compiler is required to bootstrap. The
3392 bundled compiler supports only traditional C; you will need either HP's
3393 unbundled compiler, or a binary distribution of GCC@.
3394
3395 It is possible to build GCC 3.3 starting with the bundled HP compiler,
3396 but the process requires several steps. GCC 3.3 can then be used to
3397 build later versions. The fastjar program contains ISO C code and
3398 can't be built with the HP bundled compiler. This problem can be
3399 avoided by not building the Java language. For example, use the
3400 @option{--enable-languages="c,c++,f77,objc"} option in your configure
3401 command.
3402
3403 There are several possible approaches to building the distribution.
3404 Binutils can be built first using the HP tools. Then, the GCC
3405 distribution can be built. The second approach is to build GCC
3406 first using the HP tools, then build binutils, then rebuild GCC@.
3407 There have been problems with various binary distributions, so it
3408 is best not to start from a binary distribution.
3409
3410 On 64-bit capable systems, there are two distinct targets. Different
3411 installation prefixes must be used if both are to be installed on
3412 the same system. The @samp{hppa[1-2]*-hp-hpux11*} target generates code
3413 for the 32-bit PA-RISC runtime architecture and uses the HP linker.
3414 The @samp{hppa64-hp-hpux11*} target generates 64-bit code for the
3415 PA-RISC 2.0 architecture.
3416
3417 The script config.guess now selects the target type based on the compiler
3418 detected during configuration. You must define @env{PATH} or @env{CC} so
3419 that configure finds an appropriate compiler for the initial bootstrap.
3420 When @env{CC} is used, the definition should contain the options that are
3421 needed whenever @env{CC} is used.
3422
3423 Specifically, options that determine the runtime architecture must be
3424 in @env{CC} to correctly select the target for the build. It is also
3425 convenient to place many other compiler options in @env{CC}. For example,
3426 @env{CC="cc -Ac +DA2.0W -Wp,-H16376 -D_CLASSIC_TYPES -D_HPUX_SOURCE"}
3427 can be used to bootstrap the GCC 3.3 branch with the HP compiler in
3428 64-bit K&R/bundled mode. The @option{+DA2.0W} option will result in
3429 the automatic selection of the @samp{hppa64-hp-hpux11*} target. The
3430 macro definition table of cpp needs to be increased for a successful
3431 build with the HP compiler. _CLASSIC_TYPES and _HPUX_SOURCE need to
3432 be defined when building with the bundled compiler, or when using the
3433 @option{-Ac} option. These defines aren't necessary with @option{-Ae}.
3434
3435 It is best to explicitly configure the @samp{hppa64-hp-hpux11*} target
3436 with the @option{--with-ld=@dots{}} option. This overrides the standard
3437 search for ld. The two linkers supported on this target require different
3438 commands. The default linker is determined during configuration. As a
3439 result, it's not possible to switch linkers in the middle of a GCC build.
3440 This has been reported to sometimes occur in unified builds of binutils
3441 and GCC@.
3442
3443 A recent linker patch must be installed for the correct operation of
3444 GCC 3.3 and later. @code{PHSS_26559} and @code{PHSS_24304} are the
3445 oldest linker patches that are known to work. They are for HP-UX
3446 11.00 and 11.11, respectively. @code{PHSS_24303}, the companion to
3447 @code{PHSS_24304}, might be usable but it hasn't been tested. These
3448 patches have been superseded. Consult the HP patch database to obtain
3449 the currently recommended linker patch for your system.
3450
3451 The patches are necessary for the support of weak symbols on the
3452 32-bit port, and for the running of initializers and finalizers. Weak
3453 symbols are implemented using SOM secondary definition symbols. Prior
3454 to HP-UX 11, there are bugs in the linker support for secondary symbols.
3455 The patches correct a problem of linker core dumps creating shared
3456 libraries containing secondary symbols, as well as various other
3457 linking issues involving secondary symbols.
3458
3459 GCC 3.3 uses the ELF DT_INIT_ARRAY and DT_FINI_ARRAY capabilities to
3460 run initializers and finalizers on the 64-bit port. The 32-bit port
3461 uses the linker @option{+init} and @option{+fini} options for the same
3462 purpose. The patches correct various problems with the +init/+fini
3463 options, including program core dumps. Binutils 2.14 corrects a
3464 problem on the 64-bit port resulting from HP's non-standard use of
3465 the .init and .fini sections for array initializers and finalizers.
3466
3467 Although the HP and GNU linkers are both supported for the
3468 @samp{hppa64-hp-hpux11*} target, it is strongly recommended that the
3469 HP linker be used for link editing on this target.
3470
3471 At this time, the GNU linker does not support the creation of long
3472 branch stubs. As a result, it can't successfully link binaries
3473 containing branch offsets larger than 8 megabytes. In addition,
3474 there are problems linking shared libraries, linking executables
3475 with @option{-static}, and with dwarf2 unwind and exception support.
3476 It also doesn't provide stubs for internal calls to global functions
3477 in shared libraries, so these calls can't be overloaded.
3478
3479 The HP dynamic loader does not support GNU symbol versioning, so symbol
3480 versioning is not supported. It may be necessary to disable symbol
3481 versioning with @option{--disable-symvers} when using GNU ld.
3482
3483 POSIX threads are the default. The optional DCE thread library is not
3484 supported, so @option{--enable-threads=dce} does not work.
3485
3486 @html
3487 <hr />
3488 @end html
3489 @heading @anchor{x-x-linux-gnu}*-*-linux-gnu
3490
3491 Versions of libstdc++-v3 starting with 3.2.1 require bug fixes present
3492 in glibc 2.2.5 and later. More information is available in the
3493 libstdc++-v3 documentation.
3494
3495 @html
3496 <hr />
3497 @end html
3498 @heading @anchor{ix86-x-linux}i?86-*-linux*
3499
3500 As of GCC 3.3, binutils 2.13.1 or later is required for this platform.
3501 See @uref{http://gcc.gnu.org/PR10877,,bug 10877} for more information.
3502
3503 If you receive Signal 11 errors when building on GNU/Linux, then it is
3504 possible you have a hardware problem. Further information on this can be
3505 found on @uref{http://www.bitwizard.nl/sig11/,,www.bitwizard.nl}.
3506
3507 @html
3508 <hr />
3509 @end html
3510 @heading @anchor{ix86-x-solaris289}i?86-*-solaris2.[89]
3511 The Sun assembler in Solaris 8 and 9 has several bugs and limitations.
3512 While GCC works around them, several features are missing, so it is
3513 @c FIXME: which ones?
3514 recommended to use the GNU assembler instead. There is no bundled
3515 version, but the current version, from GNU binutils 2.20.1, is known to
3516 work.
3517
3518 Solaris~2/x86 doesn't support the execution of SSE/SSE2 instructions
3519 before Solaris~9 4/04, even if the CPU supports them. Programs will
3520 receive @code{SIGILL} if they try. The fix is available both in
3521 Solaris~9 Update~6 and kernel patch 112234-12 or newer. There is no
3522 corresponding patch for Solaris 8. To avoid this problem,
3523 @option{-march} defaults to @samp{pentiumpro} on Solaris 8 and 9. If
3524 you have the patch installed, you can configure GCC with an appropriate
3525 @option{--with-arch} option, but need GNU @command{as} for SSE2 support.
3526
3527 @html
3528 <hr />
3529 @end html
3530 @heading @anchor{ix86-x-solaris210}i?86-*-solaris2.10
3531 Use this for Solaris 10 or later on x86 and x86-64 systems. This
3532 configuration is supported by GCC 4.0 and later versions only. Unlike
3533 @samp{sparcv9-sun-solaris2*}, there is no corresponding 64-bit
3534 configuration like @samp{amd64-*-solaris2*} or @samp{x86_64-*-solaris2*}.
3535 @c FIXME: will there ever be?
3536
3537 It is recommended that you configure GCC to use the GNU assembler, in
3538 @file{/usr/sfw/bin/gas}. The versions included in Solaris 10, from GNU
3539 binutils 2.15, and Solaris 11, from GNU binutils 2.19, work fine,
3540 although the current version, from GNU binutils
3541 2.20.1, is known to work, too. Recent versions of the Sun assembler in
3542 @file{/usr/ccs/bin/as} work almost as well, though.
3543 @c FIXME: as patch requirements?
3544
3545 For linking, the Sun linker, is preferred. If you want to use the GNU
3546 linker instead, which is available in @file{/usr/sfw/bin/gld}, note that
3547 due to a packaging bug the version in Solaris 10, from GNU binutils
3548 2.15, cannot be used, while the version in Solaris 11, from GNU binutils
3549 2.19, works, as does the latest version, from GNU binutils 2.20.1.
3550
3551 To use GNU @command{as}, configure with the options
3552 @option{--with-gnu-as --with-as=/usr/sfw/bin/gas}. It may be necessary
3553 to configure with @option{--without-gnu-ld --with-ld=/usr/ccs/bin/ld} to
3554 guarantee use of Sun @command{ld}.
3555 @c FIXME: why --without-gnu-ld --with-ld?
3556
3557 @html
3558 <hr />
3559 @end html
3560 @heading @anchor{ia64-x-linux}ia64-*-linux
3561 IA-64 processor (also known as IPF, or Itanium Processor Family)
3562 running GNU/Linux.
3563
3564 If you are using the installed system libunwind library with
3565 @option{--with-system-libunwind}, then you must use libunwind 0.98 or
3566 later.
3567
3568 None of the following versions of GCC has an ABI that is compatible
3569 with any of the other versions in this list, with the exception that
3570 Red Hat 2.96 and Trillian 000171 are compatible with each other:
3571 3.1, 3.0.2, 3.0.1, 3.0, Red Hat 2.96, and Trillian 000717.
3572 This primarily affects C++ programs and programs that create shared libraries.
3573 GCC 3.1 or later is recommended for compiling linux, the kernel.
3574 As of version 3.1 GCC is believed to be fully ABI compliant, and hence no
3575 more major ABI changes are expected.
3576
3577 @html
3578 <hr />
3579 @end html
3580 @heading @anchor{ia64-x-hpux}ia64-*-hpux*
3581 Building GCC on this target requires the GNU Assembler. The bundled HP
3582 assembler will not work. To prevent GCC from using the wrong assembler,
3583 the option @option{--with-gnu-as} may be necessary.
3584
3585 The GCC libunwind library has not been ported to HPUX@. This means that for
3586 GCC versions 3.2.3 and earlier, @option{--enable-libunwind-exceptions}
3587 is required to build GCC@. For GCC 3.3 and later, this is the default.
3588 For gcc 3.4.3 and later, @option{--enable-libunwind-exceptions} is
3589 removed and the system libunwind library will always be used.
3590
3591 @html
3592 <hr />
3593 <!-- rs6000-ibm-aix*, powerpc-ibm-aix* -->
3594 @end html
3595 @heading @anchor{x-ibm-aix}*-ibm-aix*
3596 Support for AIX version 3 and older was discontinued in GCC 3.4.
3597 Support for AIX version 4.2 and older was discontinued in GCC 4.5.
3598
3599 ``out of memory'' bootstrap failures may indicate a problem with
3600 process resource limits (ulimit). Hard limits are configured in the
3601 @file{/etc/security/limits} system configuration file.
3602
3603 GCC can bootstrap with recent versions of IBM XLC, but bootstrapping
3604 with an earlier release of GCC is recommended. Bootstrapping with XLC
3605 requires a larger data segment, which can be enabled through the
3606 @var{LDR_CNTRL} environment variable, e.g.,
3607
3608 @smallexample
3609 % LDR_CNTRL=MAXDATA=0x50000000
3610 % export LDR_CNTRL
3611 @end smallexample
3612
3613 One can start with a pre-compiled version of GCC to build from
3614 sources. One may delete GCC's ``fixed'' header files when starting
3615 with a version of GCC built for an earlier release of AIX.
3616
3617 To speed up the configuration phases of bootstrapping and installing GCC,
3618 one may use GNU Bash instead of AIX @command{/bin/sh}, e.g.,
3619
3620 @smallexample
3621 % CONFIG_SHELL=/opt/freeware/bin/bash
3622 % export CONFIG_SHELL
3623 @end smallexample
3624
3625 and then proceed as described in @uref{build.html,,the build
3626 instructions}, where we strongly recommend specifying an absolute path
3627 to invoke @var{srcdir}/configure.
3628
3629 Because GCC on AIX is built as a 32-bit executable by default,
3630 (although it can generate 64-bit programs) the GMP and MPFR libraries
3631 required by gfortran must be 32-bit libraries. Building GMP and MPFR
3632 as static archive libraries works better than shared libraries.
3633
3634 Errors involving @code{alloca} when building GCC generally are due
3635 to an incorrect definition of @code{CC} in the Makefile or mixing files
3636 compiled with the native C compiler and GCC@. During the stage1 phase of
3637 the build, the native AIX compiler @strong{must} be invoked as @command{cc}
3638 (not @command{xlc}). Once @command{configure} has been informed of
3639 @command{xlc}, one needs to use @samp{make distclean} to remove the
3640 configure cache files and ensure that @env{CC} environment variable
3641 does not provide a definition that will confuse @command{configure}.
3642 If this error occurs during stage2 or later, then the problem most likely
3643 is the version of Make (see above).
3644
3645 The native @command{as} and @command{ld} are recommended for bootstrapping
3646 on AIX@. The GNU Assembler, GNU Linker, and GNU Binutils version 2.20
3647 is required to bootstrap on AIX 5@. The native AIX tools do
3648 interoperate with GCC@.
3649
3650 Building @file{libstdc++.a} requires a fix for an AIX Assembler bug
3651 APAR IY26685 (AIX 4.3) or APAR IY25528 (AIX 5.1). It also requires a
3652 fix for another AIX Assembler bug and a co-dependent AIX Archiver fix
3653 referenced as APAR IY53606 (AIX 5.2) or as APAR IY54774 (AIX 5.1)
3654
3655 @samp{libstdc++} in GCC 3.4 increments the major version number of the
3656 shared object and GCC installation places the @file{libstdc++.a}
3657 shared library in a common location which will overwrite the and GCC
3658 3.3 version of the shared library. Applications either need to be
3659 re-linked against the new shared library or the GCC 3.1 and GCC 3.3
3660 versions of the @samp{libstdc++} shared object needs to be available
3661 to the AIX runtime loader. The GCC 3.1 @samp{libstdc++.so.4}, if
3662 present, and GCC 3.3 @samp{libstdc++.so.5} shared objects can be
3663 installed for runtime dynamic loading using the following steps to set
3664 the @samp{F_LOADONLY} flag in the shared object for @emph{each}
3665 multilib @file{libstdc++.a} installed:
3666
3667 Extract the shared objects from the currently installed
3668 @file{libstdc++.a} archive:
3669 @smallexample
3670 % ar -x libstdc++.a libstdc++.so.4 libstdc++.so.5
3671 @end smallexample
3672
3673 Enable the @samp{F_LOADONLY} flag so that the shared object will be
3674 available for runtime dynamic loading, but not linking:
3675 @smallexample
3676 % strip -e libstdc++.so.4 libstdc++.so.5
3677 @end smallexample
3678
3679 Archive the runtime-only shared object in the GCC 3.4
3680 @file{libstdc++.a} archive:
3681 @smallexample
3682 % ar -q libstdc++.a libstdc++.so.4 libstdc++.so.5
3683 @end smallexample
3684
3685 Linking executables and shared libraries may produce warnings of
3686 duplicate symbols. The assembly files generated by GCC for AIX always
3687 have included multiple symbol definitions for certain global variable
3688 and function declarations in the original program. The warnings should
3689 not prevent the linker from producing a correct library or runnable
3690 executable.
3691
3692 AIX 4.3 utilizes a ``large format'' archive to support both 32-bit and
3693 64-bit object modules. The routines provided in AIX 4.3.0 and AIX 4.3.1
3694 to parse archive libraries did not handle the new format correctly.
3695 These routines are used by GCC and result in error messages during
3696 linking such as ``not a COFF file''. The version of the routines shipped
3697 with AIX 4.3.1 should work for a 32-bit environment. The @option{-g}
3698 option of the archive command may be used to create archives of 32-bit
3699 objects using the original ``small format''. A correct version of the
3700 routines is shipped with AIX 4.3.2 and above.
3701
3702 Some versions of the AIX binder (linker) can fail with a relocation
3703 overflow severe error when the @option{-bbigtoc} option is used to link
3704 GCC-produced object files into an executable that overflows the TOC@. A fix
3705 for APAR IX75823 (OVERFLOW DURING LINK WHEN USING GCC AND -BBIGTOC) is
3706 available from IBM Customer Support and from its
3707 @uref{http://techsupport.services.ibm.com/,,techsupport.services.ibm.com}
3708 website as PTF U455193.
3709
3710 The AIX 4.3.2.1 linker (bos.rte.bind_cmds Level 4.3.2.1) will dump core
3711 with a segmentation fault when invoked by any version of GCC@. A fix for
3712 APAR IX87327 is available from IBM Customer Support and from its
3713 @uref{http://techsupport.services.ibm.com/,,techsupport.services.ibm.com}
3714 website as PTF U461879. This fix is incorporated in AIX 4.3.3 and above.
3715
3716 The initial assembler shipped with AIX 4.3.0 generates incorrect object
3717 files. A fix for APAR IX74254 (64BIT DISASSEMBLED OUTPUT FROM COMPILER FAILS
3718 TO ASSEMBLE/BIND) is available from IBM Customer Support and from its
3719 @uref{http://techsupport.services.ibm.com/,,techsupport.services.ibm.com}
3720 website as PTF U453956. This fix is incorporated in AIX 4.3.1 and above.
3721
3722 AIX provides National Language Support (NLS)@. Compilers and assemblers
3723 use NLS to support locale-specific representations of various data
3724 formats including floating-point numbers (e.g., @samp{.} vs @samp{,} for
3725 separating decimal fractions). There have been problems reported where
3726 GCC does not produce the same floating-point formats that the assembler
3727 expects. If one encounters this problem, set the @env{LANG}
3728 environment variable to @samp{C} or @samp{En_US}.
3729
3730 A default can be specified with the @option{-mcpu=@var{cpu_type}}
3731 switch and using the configure option @option{--with-cpu-@var{cpu_type}}.
3732
3733 @html
3734 <hr />
3735 @end html
3736 @heading @anchor{iq2000-x-elf}iq2000-*-elf
3737 Vitesse IQ2000 processors. These are used in embedded
3738 applications. There are no standard Unix configurations.
3739
3740 @html
3741 <hr />
3742 @end html
3743 @heading @anchor{lm32-x-elf}lm32-*-elf
3744 Lattice Mico32 processor.
3745 This configuration is intended for embedded systems.
3746
3747 @html
3748 <hr />
3749 @end html
3750 @heading @anchor{lm32-x-uclinux}lm32-*-uclinux
3751 Lattice Mico32 processor.
3752 This configuration is intended for embedded systems running uClinux.
3753
3754 @html
3755 <hr />
3756 @end html
3757 @heading @anchor{m32c-x-elf}m32c-*-elf
3758 Renesas M32C processor.
3759 This configuration is intended for embedded systems.
3760
3761 @html
3762 <hr />
3763 @end html
3764 @heading @anchor{m32r-x-elf}m32r-*-elf
3765 Renesas M32R processor.
3766 This configuration is intended for embedded systems.
3767
3768 @html
3769 <hr />
3770 @end html
3771 @heading @anchor{m6811-elf}m6811-elf
3772 Motorola 68HC11 family micro controllers. These are used in embedded
3773 applications. There are no standard Unix configurations.
3774
3775 @html
3776 <hr />
3777 @end html
3778 @heading @anchor{m6812-elf}m6812-elf
3779 Motorola 68HC12 family micro controllers. These are used in embedded
3780 applications. There are no standard Unix configurations.
3781
3782 @html
3783 <hr />
3784 @end html
3785 @heading @anchor{m68k-x-x}m68k-*-*
3786 By default,
3787 @samp{m68k-*-elf*}, @samp{m68k-*-rtems}, @samp{m68k-*-uclinux} and
3788 @samp{m68k-*-linux}
3789 build libraries for both M680x0 and ColdFire processors. If you only
3790 need the M680x0 libraries, you can omit the ColdFire ones by passing
3791 @option{--with-arch=m68k} to @command{configure}. Alternatively, you
3792 can omit the M680x0 libraries by passing @option{--with-arch=cf} to
3793 @command{configure}. These targets default to 5206 or 5475 code as
3794 appropriate for the target system when
3795 configured with @option{--with-arch=cf} and 68020 code otherwise.
3796
3797 The @samp{m68k-*-netbsd} and
3798 @samp{m68k-*-openbsd} targets also support the @option{--with-arch}
3799 option. They will generate ColdFire CFV4e code when configured with
3800 @option{--with-arch=cf} and 68020 code otherwise.
3801
3802 You can override the default processors listed above by configuring
3803 with @option{--with-cpu=@var{target}}. This @var{target} can either
3804 be a @option{-mcpu} argument or one of the following values:
3805 @samp{m68000}, @samp{m68010}, @samp{m68020}, @samp{m68030},
3806 @samp{m68040}, @samp{m68060}, @samp{m68020-40} and @samp{m68020-60}.
3807
3808 @html
3809 <hr />
3810 @end html
3811 @heading @anchor{m68k-x-uclinux}m68k-*-uclinux
3812 GCC 4.3 changed the uClinux configuration so that it uses the
3813 @samp{m68k-linux-gnu} ABI rather than the @samp{m68k-elf} ABI.
3814 It also added improved support for C++ and flat shared libraries,
3815 both of which were ABI changes. However, you can still use the
3816 original ABI by configuring for @samp{m68k-uclinuxoldabi} or
3817 @samp{m68k-@var{vendor}-uclinuxoldabi}.
3818
3819
3820 @html
3821 <hr />
3822 @end html
3823 @heading @anchor{mep-x-elf}mep-*-elf
3824 Toshiba Media embedded Processor.
3825 This configuration is intended for embedded systems.
3826
3827 @html
3828 <hr />
3829 @end html
3830 @heading @anchor{microblaze-x-elf}microblaze-*-elf
3831 Xilinx MicroBlaze processor.
3832 This configuration is intended for embedded systems.
3833
3834 @html
3835 <hr />
3836 @end html
3837 @heading @anchor{mips-x-x}mips-*-*
3838 If on a MIPS system you get an error message saying ``does not have gp
3839 sections for all it's [sic] sectons [sic]'', don't worry about it. This
3840 happens whenever you use GAS with the MIPS linker, but there is not
3841 really anything wrong, and it is okay to use the output file. You can
3842 stop such warnings by installing the GNU linker.
3843
3844 It would be nice to extend GAS to produce the gp tables, but they are
3845 optional, and there should not be a warning about their absence.
3846
3847 The libstdc++ atomic locking routines for MIPS targets requires MIPS II
3848 and later. A patch went in just after the GCC 3.3 release to
3849 make @samp{mips*-*-*} use the generic implementation instead. You can also
3850 configure for @samp{mipsel-elf} as a workaround. The
3851 @samp{mips*-*-linux*} target continues to use the MIPS II routines. More
3852 work on this is expected in future releases.
3853
3854 @c If you make --with-llsc the default for another target, please also
3855 @c update the description of the --with-llsc option.
3856
3857 The built-in @code{__sync_*} functions are available on MIPS II and
3858 later systems and others that support the @samp{ll}, @samp{sc} and
3859 @samp{sync} instructions. This can be overridden by passing
3860 @option{--with-llsc} or @option{--without-llsc} when configuring GCC.
3861 Since the Linux kernel emulates these instructions if they are
3862 missing, the default for @samp{mips*-*-linux*} targets is
3863 @option{--with-llsc}. The @option{--with-llsc} and
3864 @option{--without-llsc} configure options may be overridden at compile
3865 time by passing the @option{-mllsc} or @option{-mno-llsc} options to
3866 the compiler.
3867
3868 MIPS systems check for division by zero (unless
3869 @option{-mno-check-zero-division} is passed to the compiler) by
3870 generating either a conditional trap or a break instruction. Using
3871 trap results in smaller code, but is only supported on MIPS II and
3872 later. Also, some versions of the Linux kernel have a bug that
3873 prevents trap from generating the proper signal (@code{SIGFPE}). To enable
3874 the use of break, use the @option{--with-divide=breaks}
3875 @command{configure} option when configuring GCC@. The default is to
3876 use traps on systems that support them.
3877
3878 Cross-compilers for the MIPS as target using the MIPS assembler
3879 currently do not work, because the auxiliary programs
3880 @file{mips-tdump.c} and @file{mips-tfile.c} can't be compiled on
3881 anything but a MIPS@. It does work to cross compile for a MIPS
3882 if you use the GNU assembler and linker.
3883
3884 The assembler from GNU binutils 2.17 and earlier has a bug in the way
3885 it sorts relocations for REL targets (o32, o64, EABI). This can cause
3886 bad code to be generated for simple C++ programs. Also the linker
3887 from GNU binutils versions prior to 2.17 has a bug which causes the
3888 runtime linker stubs in very large programs, like @file{libgcj.so}, to
3889 be incorrectly generated. GNU Binutils 2.18 and later (and snapshots
3890 made after Nov. 9, 2006) should be free from both of these problems.
3891
3892 @html
3893 <hr />
3894 @end html
3895 @heading @anchor{mips-sgi-irix5}mips-sgi-irix5
3896
3897 Support for IRIX 5 has been removed in GCC 4.6.
3898
3899 @html
3900 <hr />
3901 @end html
3902 @heading @anchor{mips-sgi-irix6}mips-sgi-irix6
3903
3904 Support for IRIX 6 releases before 6.5 has been removed in GCC 4.6, as
3905 well as support for
3906 the O32 ABI. It is @emph{strongly} recommended to upgrade to at least
3907 IRIX 6.5.18. This release introduced full ISO C99 support, though for
3908 the N32 and N64 ABIs only.
3909
3910 To build and use GCC on IRIX 6.5, you need the IRIX Development Foundation
3911 (IDF) and IRIX Development Libraries (IDL). They are included with the
3912 IRIX 6.5 media.
3913
3914 If you are using SGI's MIPSpro @command{cc} as your bootstrap compiler, you must
3915 ensure that the N32 ABI is in use. To test this, compile a simple C
3916 file with @command{cc} and then run @command{file} on the
3917 resulting object file. The output should look like:
3918
3919 @smallexample
3920 test.o: ELF N32 MSB @dots{}
3921 @end smallexample
3922
3923 @noindent
3924 If you see:
3925
3926 @smallexample
3927 test.o: ELF 32-bit MSB @dots{}
3928 @end smallexample
3929
3930 @noindent
3931 or
3932
3933 @smallexample
3934 test.o: ELF 64-bit MSB @dots{}
3935 @end smallexample
3936
3937 @noindent
3938 then your version of @command{cc} uses the O32 or N64 ABI by default. You
3939 should set the environment variable @env{CC} to @samp{cc -n32}
3940 before configuring GCC@.
3941
3942 If you want the resulting @command{gcc} to run on old 32-bit systems
3943 with the MIPS R4400 CPU, you need to ensure that only code for the @samp{mips3}
3944 instruction set architecture (ISA) is generated. While GCC 3.x does
3945 this correctly, both GCC 2.95 and SGI's MIPSpro @command{cc} may change
3946 the ISA depending on the machine where GCC is built. Using one of them
3947 as the bootstrap compiler may result in @samp{mips4} code, which won't run at
3948 all on @samp{mips3}-only systems. For the test program above, you should see:
3949
3950 @smallexample
3951 test.o: ELF N32 MSB mips-3 @dots{}
3952 @end smallexample
3953
3954 @noindent
3955 If you get:
3956
3957 @smallexample
3958 test.o: ELF N32 MSB mips-4 @dots{}
3959 @end smallexample
3960
3961 @noindent
3962 instead, you should set the environment variable @env{CC} to @samp{cc
3963 -n32 -mips3} or @samp{gcc -mips3} respectively before configuring GCC@.
3964
3965 MIPSpro C 7.4 may cause bootstrap failures, due to a bug when inlining
3966 @code{memcmp}. Either add @code{-U__INLINE_INTRINSICS} to the @env{CC}
3967 environment variable as a workaround or upgrade to MIPSpro C 7.4.1m.
3968
3969 GCC on IRIX 6.5 is usually built to support the N32 and N64 ABIs. If
3970 you build GCC on a system that doesn't have the N64 libraries installed
3971 or cannot run 64-bit binaries,
3972 you need to configure with @option{--disable-multilib} so GCC doesn't
3973 try to use them.
3974 Look for @file{/usr/lib64/libc.so.1} to see if you
3975 have the 64-bit libraries installed.
3976
3977 GCC must be configured with GNU @command{as}. The latest version, from GNU
3978 binutils 2.20.1, is known to work. On the other hand, bootstrap fails
3979 with GNU @command{ld} at least since GNU binutils 2.17.
3980
3981 The @option{--enable-libgcj}
3982 option is disabled by default: IRIX 6 uses a very low default limit
3983 (20480) for the command line length. Although @command{libtool} contains a
3984 workaround for this problem, at least the N64 @samp{libgcj} is known not
3985 to build despite this, running into an internal error of the native
3986 @command{ld}. A sure fix is to increase this limit (@samp{ncargs}) to
3987 its maximum of 262144 bytes. If you have root access, you can use the
3988 @command{systune} command to do this.
3989 @c FIXME: does this work with current libtool?
3990
3991 @code{wchar_t} support in @samp{libstdc++} is not available for old
3992 IRIX 6.5.x releases, @math{x < 19}. The problem cannot be autodetected
3993 and in order to build GCC for such targets you need to configure with
3994 @option{--disable-wchar_t}.
3995
3996 @html
3997 <hr />
3998 @end html
3999 @heading @anchor{moxie-x-elf}moxie-*-elf
4000 The moxie processor. See @uref{http://moxielogic.org/} for more
4001 information about this processor.
4002
4003 @html
4004 <hr />
4005 @end html
4006 @heading @anchor{powerpc-x-x}powerpc-*-*
4007
4008 You can specify a default version for the @option{-mcpu=@var{cpu_type}}
4009 switch by using the configure option @option{--with-cpu-@var{cpu_type}}.
4010
4011 You will need
4012 @uref{ftp://ftp.kernel.org/pub/linux/devel/binutils,,binutils 2.15}
4013 or newer for a working GCC@.
4014
4015 @html
4016 <hr />
4017 @end html
4018 @heading @anchor{powerpc-x-darwin}powerpc-*-darwin*
4019 PowerPC running Darwin (Mac OS X kernel).
4020
4021 Pre-installed versions of Mac OS X may not include any developer tools,
4022 meaning that you will not be able to build GCC from source. Tool
4023 binaries are available at
4024 @uref{http://developer.apple.com/darwin/projects/compiler/} (free
4025 registration required).
4026
4027 This version of GCC requires at least cctools-590.36. The
4028 cctools-590.36 package referenced from
4029 @uref{http://gcc.gnu.org/ml/gcc/2006-03/msg00507.html} will not work
4030 on systems older than 10.3.9 (aka darwin7.9.0).
4031
4032 @html
4033 <hr />
4034 @end html
4035 @heading @anchor{powerpc-x-elf}powerpc-*-elf
4036 PowerPC system in big endian mode, running System V.4.
4037
4038 @html
4039 <hr />
4040 @end html
4041 @heading @anchor{powerpc-x-linux-gnu}powerpc*-*-linux-gnu*
4042
4043 PowerPC system in big endian mode running Linux.
4044
4045 @html
4046 <hr />
4047 @end html
4048 @heading @anchor{powerpc-x-netbsd}powerpc-*-netbsd*
4049 PowerPC system in big endian mode running NetBSD@.
4050
4051 @html
4052 <hr />
4053 @end html
4054 @heading @anchor{powerpc-x-eabisim}powerpc-*-eabisim
4055 Embedded PowerPC system in big endian mode for use in running under the
4056 PSIM simulator.
4057
4058 @html
4059 <hr />
4060 @end html
4061 @heading @anchor{powerpc-x-eabi}powerpc-*-eabi
4062 Embedded PowerPC system in big endian mode.
4063
4064 @html
4065 <hr />
4066 @end html
4067 @heading @anchor{powerpcle-x-elf}powerpcle-*-elf
4068 PowerPC system in little endian mode, running System V.4.
4069
4070 @html
4071 <hr />
4072 @end html
4073 @heading @anchor{powerpcle-x-eabisim}powerpcle-*-eabisim
4074 Embedded PowerPC system in little endian mode for use in running under
4075 the PSIM simulator.
4076
4077 @html
4078 <hr />
4079 @end html
4080 @heading @anchor{powerpcle-x-eabi}powerpcle-*-eabi
4081 Embedded PowerPC system in little endian mode.
4082
4083 @html
4084 <hr />
4085 @end html
4086 @heading @anchor{rx-x-elf}rx-*-elf
4087 The Renesas RX processor. See
4088 @uref{http://eu.renesas.com/fmwk.jsp?cnt=rx600_series_landing.jsp&fp=/products/mpumcu/rx_family/rx600_series}
4089 for more information about this processor.
4090
4091 @html
4092 <hr />
4093 @end html
4094 @heading @anchor{s390-x-linux}s390-*-linux*
4095 S/390 system running GNU/Linux for S/390@.
4096
4097 @html
4098 <hr />
4099 @end html
4100 @heading @anchor{s390x-x-linux}s390x-*-linux*
4101 zSeries system (64-bit) running GNU/Linux for zSeries@.
4102
4103 @html
4104 <hr />
4105 @end html
4106 @heading @anchor{s390x-ibm-tpf}s390x-ibm-tpf*
4107 zSeries system (64-bit) running TPF@. This platform is
4108 supported as cross-compilation target only.
4109
4110 @html
4111 <hr />
4112 @end html
4113 @c Please use Solaris 2 to refer to all release of Solaris, starting
4114 @c with 2.0 until 2.6, 7, 8, etc. Solaris 1 was a marketing name for
4115 @c SunOS 4 releases which we don't use to avoid confusion. Solaris
4116 @c alone is too unspecific and must be avoided.
4117 @heading @anchor{x-x-solaris2}*-*-solaris2*
4118
4119 Support for Solaris 7 has been removed in GCC 4.6.
4120
4121 Sun does not ship a C compiler with Solaris 2, though you can download
4122 the Sun Studio compilers for free from
4123 @uref{http://developers.sun.com/sunstudio/downloads/}. Alternatively,
4124 you can install a pre-built GCC to bootstrap and install GCC. See the
4125 @uref{binaries.html,,binaries page} for details.
4126
4127 The Solaris 2 @command{/bin/sh} will often fail to configure
4128 @samp{libstdc++-v3}, @samp{boehm-gc} or @samp{libjava}. We therefore
4129 recommend using the following initial sequence of commands
4130
4131 @smallexample
4132 % CONFIG_SHELL=/bin/ksh
4133 % export CONFIG_SHELL
4134 @end smallexample
4135
4136 @noindent
4137 and proceed as described in @uref{configure.html,,the configure instructions}.
4138 In addition we strongly recommend specifying an absolute path to invoke
4139 @command{@var{srcdir}/configure}.
4140
4141 Solaris 2 comes with a number of optional OS packages. Some of these
4142 are needed to use GCC fully, namely @code{SUNWarc},
4143 @code{SUNWbtool}, @code{SUNWesu}, @code{SUNWhea}, @code{SUNWlibm},
4144 @code{SUNWsprot}, and @code{SUNWtoo}. If you did not install all
4145 optional packages when installing Solaris 2, you will need to verify that
4146 the packages that GCC needs are installed.
4147
4148 To check whether an optional package is installed, use
4149 the @command{pkginfo} command. To add an optional package, use the
4150 @command{pkgadd} command. For further details, see the Solaris 2
4151 documentation.
4152
4153 Trying to use the linker and other tools in
4154 @file{/usr/ucb} to install GCC has been observed to cause trouble.
4155 For example, the linker may hang indefinitely. The fix is to remove
4156 @file{/usr/ucb} from your @env{PATH}.
4157
4158 The build process works more smoothly with the legacy Sun tools so, if you
4159 have @file{/usr/xpg4/bin} in your @env{PATH}, we recommend that you place
4160 @file{/usr/bin} before @file{/usr/xpg4/bin} for the duration of the build.
4161
4162 We recommend the use of the Sun assembler or the GNU assembler, in
4163 conjunction with the Sun linker. The GNU @command{as}
4164 versions included in Solaris 10, from GNU binutils 2.15, and Solaris 11,
4165 from GNU binutils 2.19, are known to work. They can be found in
4166 @file{/usr/sfw/bin/gas}. Current versions of GNU binutils (2.20.1)
4167 are known to work as well. Note that your mileage may vary
4168 if you use a combination of the GNU tools and the Sun tools: while the
4169 combination GNU @command{as} + Sun @command{ld} should reasonably work,
4170 the reverse combination Sun @command{as} + GNU @command{ld} is known to
4171 cause memory corruption at runtime in some cases for C++ programs.
4172 @c FIXME: still?
4173 GNU @command{ld} usually works as well, although the version included in
4174 Solaris 10 cannot be used due to several bugs. Again, the current
4175 version (2.20.1) is known to work, but generally lacks platform specific
4176 features, so better stay with Sun @command{ld}.
4177
4178 To enable symbol versioning in @samp{libstdc++} with Sun @command{ld},
4179 you need to have any version of GNU @command{c++filt}, which is part of
4180 GNU binutils. @samp{libstdc++} symbol versioning will be disabled if no
4181 appropriate version is found. Sun @command{c++filt} from the Sun Studio
4182 compilers does @emph{not} work.
4183
4184 Sun bug 4296832 turns up when compiling X11 headers with GCC 2.95 or
4185 newer: @command{g++} will complain that types are missing. These headers
4186 assume that omitting the type means @code{int}; this assumption worked for
4187 C90 but is wrong for C++, and is now wrong for C99 also.
4188
4189 @command{g++} accepts such (invalid) constructs with the option
4190 @option{-fpermissive}; it will assume that any missing type is @code{int}
4191 (as defined by C90).
4192
4193 There are patches for Solaris 8 (108652-24 or newer for SPARC,
4194 108653-22 for Intel) that fix this bug.
4195
4196 Sun bug 4927647 sometimes causes random spurious testsuite failures
4197 related to missing diagnostic output. This bug doesn't affect GCC
4198 itself, rather it is a kernel bug triggered by the @command{expect}
4199 program which is used only by the GCC testsuite driver. When the bug
4200 causes the @command{expect} program to miss anticipated output, extra
4201 testsuite failures appear.
4202
4203 There are patches for Solaris 8 (117350-12 or newer for SPARC,
4204 117351-12 or newer for Intel) and Solaris 9 (117171-11 or newer for
4205 SPARC, 117172-11 or newer for Intel) that address this problem.
4206
4207 Solaris~8 provides an alternate implementation of the thread libraries,
4208 @samp{libpthread} and @samp{libthread}. They are required for TLS
4209 support and have been made the default in Solaris~9, so they are always
4210 used on Solaris~8.
4211
4212 Thread-local storage (TLS) is supported in Solaris~8 and 9, but requires
4213 some patches. The @samp{libthread} patches provide the
4214 @code{__tls_get_addr} (SPARC, 64-bit x86) resp.@ @code{___tls_get_addr}
4215 (32-bit x86) functions. On Solaris~8, you need 108993-26 or newer on
4216 SPARC, 108994-26 or newer on Intel. On Solaris~9, the necessary support
4217 on SPARC is present since FCS, while 114432-05 or newer is reqired on
4218 Intel. Additionally, on Solaris~8, patch 109147-14 or newer on SPARC or
4219 109148-22 or newer on Intel are required for the Sun @command{ld} and
4220 runtime linker (@command{ld.so.1}) support. Again, Solaris~9/SPARC
4221 works since FCS, while 113986-02 is required on Intel. The linker
4222 patches must be installed even if GNU @command{ld} is used. Sun
4223 @command{as} in Solaris~8 and 9 doesn't support the necessary
4224 relocations, so GNU @command{as} must be used. The @command{configure}
4225 script checks for those prerequisites and automatically enables TLS
4226 support if they are met. Although those minimal patch versions should
4227 work, it is recommended to use the latest patch versions which include
4228 additional bug fixes.
4229
4230 @html
4231 <hr />
4232 @end html
4233 @heading @anchor{sparc-x-x}sparc*-*-*
4234
4235 This section contains general configuration information for all
4236 SPARC-based platforms. In addition to reading this section, please
4237 read all other sections that match your target.
4238
4239 Newer versions of the GNU Multiple Precision Library (GMP), the MPFR
4240 library and the MPC library are known to be miscompiled by earlier
4241 versions of GCC on these platforms. We therefore recommend the use
4242 of the exact versions of these libraries listed as minimal versions
4243 in @uref{prerequisites.html,,the prerequisites}.
4244
4245 @html
4246 <hr />
4247 @end html
4248 @heading @anchor{sparc-sun-solaris2}sparc-sun-solaris2*
4249
4250 When GCC is configured to use GNU binutils 2.14 or later, the binaries
4251 produced are smaller than the ones produced using Sun's native tools;
4252 this difference is quite significant for binaries containing debugging
4253 information.
4254
4255 Starting with Solaris 7, the operating system is capable of executing
4256 64-bit SPARC V9 binaries. GCC 3.1 and later properly supports
4257 this; the @option{-m64} option enables 64-bit code generation.
4258 However, if all you want is code tuned for the UltraSPARC CPU, you
4259 should try the @option{-mtune=ultrasparc} option instead, which produces
4260 code that, unlike full 64-bit code, can still run on non-UltraSPARC
4261 machines.
4262
4263 When configuring on a Solaris 7 or later system that is running a kernel
4264 that supports only 32-bit binaries, one must configure with
4265 @option{--disable-multilib}, since we will not be able to build the
4266 64-bit target libraries.
4267
4268 GCC 3.3 and GCC 3.4 trigger code generation bugs in earlier versions of
4269 the GNU compiler (especially GCC 3.0.x versions), which lead to the
4270 miscompilation of the stage1 compiler and the subsequent failure of the
4271 bootstrap process. A workaround is to use GCC 3.2.3 as an intermediary
4272 stage, i.e.@: to bootstrap that compiler with the base compiler and then
4273 use it to bootstrap the final compiler.
4274
4275 GCC 3.4 triggers a code generation bug in versions 5.4 (Sun ONE Studio 7)
4276 and 5.5 (Sun ONE Studio 8) of the Sun compiler, which causes a bootstrap
4277 failure in form of a miscompilation of the stage1 compiler by the Sun
4278 compiler. This is Sun bug 4974440. This is fixed with patch 112760-07.
4279
4280 GCC 3.4 changed the default debugging format from Stabs to DWARF-2 for
4281 32-bit code on Solaris 7 and later. If you use the Sun assembler, this
4282 change apparently runs afoul of Sun bug 4910101 (which is referenced as
4283 an x86-only problem by Sun, probably because they do not use DWARF-2).
4284 A symptom of the problem is that you cannot compile C++ programs like
4285 @command{groff} 1.19.1 without getting messages similar to the following:
4286
4287 @smallexample
4288 ld: warning: relocation error: R_SPARC_UA32: @dots{}
4289 external symbolic relocation against non-allocatable section
4290 .debug_info cannot be processed at runtime: relocation ignored.
4291 @end smallexample
4292
4293 @noindent
4294 To work around this problem, compile with @option{-gstabs+} instead of
4295 plain @option{-g}.
4296
4297 When configuring the GNU Multiple Precision Library (GMP), the MPFR
4298 library or the MPC library on a Solaris 7 or later system, the canonical
4299 target triplet must be specified as the @command{build} parameter on the
4300 configure line. This target triplet can be obtained by invoking @command{./config.guess} in the toplevel source directory of GCC (and
4301 not that of GMP or MPFR or MPC). For example on a Solaris 9 system:
4302
4303 @smallexample
4304 % ./configure --build=sparc-sun-solaris2.9 --prefix=xxx
4305 @end smallexample
4306
4307 @html
4308 <hr />
4309 @end html
4310 @heading @anchor{sparc-sun-solaris210}sparc-sun-solaris2.10
4311
4312 There is a bug in older versions of the Sun assembler which breaks
4313 thread-local storage (TLS). A typical error message is
4314
4315 @smallexample
4316 ld: fatal: relocation error: R_SPARC_TLS_LE_HIX22: file /var/tmp//ccamPA1v.o:
4317 symbol <unknown>: bad symbol type SECT: symbol type must be TLS
4318 @end smallexample
4319
4320 @noindent
4321 This bug is fixed in Sun patch 118683-03 or later.
4322
4323 @html
4324 <hr />
4325 @end html
4326 @heading @anchor{sparc-x-linux}sparc-*-linux*
4327
4328 GCC versions 3.0 and higher require binutils 2.11.2 and glibc 2.2.4
4329 or newer on this platform. All earlier binutils and glibc
4330 releases mishandled unaligned relocations on @code{sparc-*-*} targets.
4331
4332
4333 @html
4334 <hr />
4335 @end html
4336 @heading @anchor{sparc64-x-solaris2}sparc64-*-solaris2*
4337
4338 When configuring the GNU Multiple Precision Library (GMP) or the
4339 MPFR library, the canonical target triplet must be specified as
4340 the @command{build} parameter on the configure line. For example
4341 on a Solaris 9 system:
4342
4343 @smallexample
4344 % ./configure --build=sparc64-sun-solaris2.9 --prefix=xxx
4345 @end smallexample
4346
4347 The following compiler flags must be specified in the configure
4348 step in order to bootstrap this target with the Sun compiler:
4349
4350 @smallexample
4351 % CC="cc -xarch=v9 -xildoff" @var{srcdir}/configure [@var{options}] [@var{target}]
4352 @end smallexample
4353
4354 @noindent
4355 @option{-xarch=v9} specifies the SPARC-V9 architecture to the Sun toolchain
4356 and @option{-xildoff} turns off the incremental linker.
4357
4358 @html
4359 <hr />
4360 @end html
4361 @heading @anchor{sparcv9-x-solaris2}sparcv9-*-solaris2*
4362
4363 This is a synonym for @samp{sparc64-*-solaris2*}.
4364
4365 @html
4366 <hr />
4367 @end html
4368 @heading @anchor{x-x-vxworks}*-*-vxworks*
4369 Support for VxWorks is in flux. At present GCC supports @emph{only} the
4370 very recent VxWorks 5.5 (aka Tornado 2.2) release, and only on PowerPC@.
4371 We welcome patches for other architectures supported by VxWorks 5.5.
4372 Support for VxWorks AE would also be welcome; we believe this is merely
4373 a matter of writing an appropriate ``configlette'' (see below). We are
4374 not interested in supporting older, a.out or COFF-based, versions of
4375 VxWorks in GCC 3.
4376
4377 VxWorks comes with an older version of GCC installed in
4378 @file{@var{$WIND_BASE}/host}; we recommend you do not overwrite it.
4379 Choose an installation @var{prefix} entirely outside @var{$WIND_BASE}.
4380 Before running @command{configure}, create the directories @file{@var{prefix}}
4381 and @file{@var{prefix}/bin}. Link or copy the appropriate assembler,
4382 linker, etc.@: into @file{@var{prefix}/bin}, and set your @var{PATH} to
4383 include that directory while running both @command{configure} and
4384 @command{make}.
4385
4386 You must give @command{configure} the
4387 @option{--with-headers=@var{$WIND_BASE}/target/h} switch so that it can
4388 find the VxWorks system headers. Since VxWorks is a cross compilation
4389 target only, you must also specify @option{--target=@var{target}}.
4390 @command{configure} will attempt to create the directory
4391 @file{@var{prefix}/@var{target}/sys-include} and copy files into it;
4392 make sure the user running @command{configure} has sufficient privilege
4393 to do so.
4394
4395 GCC's exception handling runtime requires a special ``configlette''
4396 module, @file{contrib/gthr_supp_vxw_5x.c}. Follow the instructions in
4397 that file to add the module to your kernel build. (Future versions of
4398 VxWorks will incorporate this module.)
4399
4400 @html
4401 <hr />
4402 @end html
4403 @heading @anchor{x86-64-x-x}x86_64-*-*, amd64-*-*
4404
4405 GCC supports the x86-64 architecture implemented by the AMD64 processor
4406 (amd64-*-* is an alias for x86_64-*-*) on GNU/Linux, FreeBSD and NetBSD@.
4407 On GNU/Linux the default is a bi-arch compiler which is able to generate
4408 both 64-bit x86-64 and 32-bit x86 code (via the @option{-m32} switch).
4409
4410 @html
4411 <hr />
4412 @end html
4413 @heading @anchor{xtensa-x-elf}xtensa*-*-elf
4414
4415 This target is intended for embedded Xtensa systems using the
4416 @samp{newlib} C library. It uses ELF but does not support shared
4417 objects. Designed-defined instructions specified via the
4418 Tensilica Instruction Extension (TIE) language are only supported
4419 through inline assembly.
4420
4421 The Xtensa configuration information must be specified prior to
4422 building GCC@. The @file{include/xtensa-config.h} header
4423 file contains the configuration information. If you created your
4424 own Xtensa configuration with the Xtensa Processor Generator, the
4425 downloaded files include a customized copy of this header file,
4426 which you can use to replace the default header file.
4427
4428 @html
4429 <hr />
4430 @end html
4431 @heading @anchor{xtensa-x-linux}xtensa*-*-linux*
4432
4433 This target is for Xtensa systems running GNU/Linux. It supports ELF
4434 shared objects and the GNU C library (glibc). It also generates
4435 position-independent code (PIC) regardless of whether the
4436 @option{-fpic} or @option{-fPIC} options are used. In other
4437 respects, this target is the same as the
4438 @uref{#xtensa*-*-elf,,@samp{xtensa*-*-elf}} target.
4439
4440 @html
4441 <hr />
4442 @end html
4443 @heading @anchor{windows}Microsoft Windows
4444
4445 @subheading Intel 16-bit versions
4446 The 16-bit versions of Microsoft Windows, such as Windows 3.1, are not
4447 supported.
4448
4449 However, the 32-bit port has limited support for Microsoft
4450 Windows 3.11 in the Win32s environment, as a target only. See below.
4451
4452 @subheading Intel 32-bit versions
4453
4454 The 32-bit versions of Windows, including Windows 95, Windows NT, Windows
4455 XP, and Windows Vista, are supported by several different target
4456 platforms. These targets differ in which Windows subsystem they target
4457 and which C libraries are used.
4458
4459 @itemize
4460 @item Cygwin @uref{#x-x-cygwin,,*-*-cygwin}: Cygwin provides a user-space
4461 Linux API emulation layer in the Win32 subsystem.
4462 @item Interix @uref{#x-x-interix,,*-*-interix}: The Interix subsystem
4463 provides native support for POSIX.
4464 @item MinGW @uref{#x-x-mingw32,,*-*-mingw32}: MinGW is a native GCC port for
4465 the Win32 subsystem that provides a subset of POSIX.
4466 @item MKS i386-pc-mks: NuTCracker from MKS. See
4467 @uref{http://www.mkssoftware.com/} for more information.
4468 @end itemize
4469
4470 @subheading Intel 64-bit versions
4471
4472 GCC contains support for x86-64 using the mingw-w64
4473 runtime library, available from @uref{http://mingw-w64.sourceforge.net/}.
4474 This library should be used with the target triple x86_64-pc-mingw32.
4475
4476 Presently Windows for Itanium is not supported.
4477
4478 @subheading Windows CE
4479
4480 Windows CE is supported as a target only on ARM (arm-wince-pe), Hitachi
4481 SuperH (sh-wince-pe), and MIPS (mips-wince-pe).
4482
4483 @subheading Other Windows Platforms
4484
4485 GCC no longer supports Windows NT on the Alpha or PowerPC.
4486
4487 GCC no longer supports the Windows POSIX subsystem. However, it does
4488 support the Interix subsystem. See above.
4489
4490 Old target names including *-*-winnt and *-*-windowsnt are no longer used.
4491
4492 PW32 (i386-pc-pw32) support was never completed, and the project seems to
4493 be inactive. See @uref{http://pw32.sourceforge.net/} for more information.
4494
4495 UWIN support has been removed due to a lack of maintenance.
4496
4497 @html
4498 <hr />
4499 @end html
4500 @heading @anchor{x-x-cygwin}*-*-cygwin
4501
4502 Ports of GCC are included with the
4503 @uref{http://www.cygwin.com/,,Cygwin environment}.
4504
4505 GCC will build under Cygwin without modification; it does not build
4506 with Microsoft's C++ compiler and there are no plans to make it do so.
4507
4508 The Cygwin native compiler can be configured to target any 32-bit x86
4509 cpu architecture desired; the default is i686-pc-cygwin. It should be
4510 used with as up-to-date a version of binutils as possible; use either
4511 the latest official GNU binutils release in the Cygwin distribution,
4512 or version 2.20 or above if building your own.
4513
4514 @html
4515 <hr />
4516 @end html
4517 @heading @anchor{x-x-interix}*-*-interix
4518
4519 The Interix target is used by OpenNT, Interix, Services For UNIX (SFU),
4520 and Subsystem for UNIX-based Applications (SUA). Applications compiled
4521 with this target run in the Interix subsystem, which is separate from
4522 the Win32 subsystem. This target was last known to work in GCC 3.3.
4523
4524 For more information, see @uref{http://www.interix.com/}.
4525
4526 @html
4527 <hr />
4528 @end html
4529 @heading @anchor{x-x-mingw32}*-*-mingw32
4530
4531 GCC will build with and support only MinGW runtime 3.12 and later.
4532 Earlier versions of headers are incompatible with the new default semantics
4533 of @code{extern inline} in @code{-std=c99} and @code{-std=gnu99} modes.
4534
4535 @html
4536 <hr />
4537 @end html
4538 @heading @anchor{older}Older systems
4539
4540 GCC contains support files for many older (1980s and early
4541 1990s) Unix variants. For the most part, support for these systems
4542 has not been deliberately removed, but it has not been maintained for
4543 several years and may suffer from bitrot.
4544
4545 Starting with GCC 3.1, each release has a list of ``obsoleted'' systems.
4546 Support for these systems is still present in that release, but
4547 @command{configure} will fail unless the @option{--enable-obsolete}
4548 option is given. Unless a maintainer steps forward, support for these
4549 systems will be removed from the next release of GCC@.
4550
4551 Support for old systems as hosts for GCC can cause problems if the
4552 workarounds for compiler, library and operating system bugs affect the
4553 cleanliness or maintainability of the rest of GCC@. In some cases, to
4554 bring GCC up on such a system, if still possible with current GCC, may
4555 require first installing an old version of GCC which did work on that
4556 system, and using it to compile a more recent GCC, to avoid bugs in the
4557 vendor compiler. Old releases of GCC 1 and GCC 2 are available in the
4558 @file{old-releases} directory on the @uref{../mirrors.html,,GCC mirror
4559 sites}. Header bugs may generally be avoided using
4560 @command{fixincludes}, but bugs or deficiencies in libraries and the
4561 operating system may still cause problems.
4562
4563 Support for older systems as targets for cross-compilation is less
4564 problematic than support for them as hosts for GCC; if an enthusiast
4565 wishes to make such a target work again (including resurrecting any of
4566 the targets that never worked with GCC 2, starting from the last
4567 version before they were removed), patches
4568 @uref{../contribute.html,,following the usual requirements} would be
4569 likely to be accepted, since they should not affect the support for more
4570 modern targets.
4571
4572 For some systems, old versions of GNU binutils may also be useful,
4573 and are available from @file{pub/binutils/old-releases} on
4574 @uref{http://sourceware.org/mirrors.html,,sourceware.org mirror sites}.
4575
4576 Some of the information on specific systems above relates to
4577 such older systems, but much of the information
4578 about GCC on such systems (which may no longer be applicable to
4579 current GCC) is to be found in the GCC texinfo manual.
4580
4581 @html
4582 <hr />
4583 @end html
4584 @heading @anchor{elf}all ELF targets (SVR4, Solaris 2, etc.)
4585
4586 C++ support is significantly better on ELF targets if you use the
4587 @uref{./configure.html#with-gnu-ld,,GNU linker}; duplicate copies of
4588 inlines, vtables and template instantiations will be discarded
4589 automatically.
4590
4591
4592 @html
4593 <hr />
4594 <p>
4595 @end html
4596 @ifhtml
4597 @uref{./index.html,,Return to the GCC Installation page}
4598 @end ifhtml
4599 @end ifset
4600
4601 @c ***Old documentation******************************************************
4602 @ifset oldhtml
4603 @include install-old.texi
4604 @html
4605 <hr />
4606 <p>
4607 @end html
4608 @ifhtml
4609 @uref{./index.html,,Return to the GCC Installation page}
4610 @end ifhtml
4611 @end ifset
4612
4613 @c ***GFDL********************************************************************
4614 @ifset gfdlhtml
4615 @include fdl.texi
4616 @html
4617 <hr />
4618 <p>
4619 @end html
4620 @ifhtml
4621 @uref{./index.html,,Return to the GCC Installation page}
4622 @end ifhtml
4623 @end ifset
4624
4625 @c ***************************************************************************
4626 @c Part 6 The End of the Document
4627 @ifinfo
4628 @comment node-name, next, previous, up
4629 @node Concept Index, , GNU Free Documentation License, Top
4630 @end ifinfo
4631
4632 @ifinfo
4633 @unnumbered Concept Index
4634
4635 @printindex cp
4636
4637 @contents
4638 @end ifinfo
4639 @bye