3 <title>Installing GCC: Configuration</title>
4 <meta http-equiv="Content-Type" content="text/html">
5 <meta name="description" content="Installing GCC: Configuration">
6 <meta name="generator" content="makeinfo 4.13">
7 <link title="Top" rel="top" href="#Top">
8 <link href="http://www.gnu.org/software/texinfo/" rel="generator-home" title="Texinfo Homepage">
10 Copyright (C) 1988-2013 Free Software Foundation, Inc.
12 Permission is granted to copy, distribute and/or modify this document
13 under the terms of the GNU Free Documentation License, Version 1.3 or
14 any later version published by the Free Software Foundation; with no
15 Invariant Sections, the Front-Cover texts being (a) (see below), and
16 with the Back-Cover Texts being (b) (see below). A copy of the
17 license is included in the section entitled "GNU Free Documentation License".
19 (a) The FSF's Front-Cover Text is:
23 (b) The FSF's Back-Cover Text is:
25 You have freedom to copy and modify this GNU Manual, like GNU
26 software. Copies published by the Free Software Foundation raise
27 funds for GNU development.-->
28 <meta http-equiv="Content-Style-Type" content="text/css">
29 <style type="text/css"><!--
30 pre.display { font-family:inherit }
31 pre.format { font-family:inherit }
32 pre.smalldisplay { font-family:inherit; font-size:smaller }
33 pre.smallformat { font-family:inherit; font-size:smaller }
34 pre.smallexample { font-size:smaller }
35 pre.smalllisp { font-size:smaller }
36 span.sc { font-variant:small-caps }
37 span.roman { font-family:serif; font-weight:normal; }
38 span.sansserif { font-family:sans-serif; font-weight:normal; }
42 <h1 class="settitle">Installing GCC: Configuration</h1>
43 <a name="index-Configuration-1"></a><a name="index-Installing-GCC_003a-Configuration-2"></a>
44 Like most GNU software, GCC must be configured before it can be built.
45 This document describes the recommended configuration procedure
46 for both native and cross targets.
48 <p>We use <var>srcdir</var> to refer to the toplevel source directory for
49 GCC; we use <var>objdir</var> to refer to the toplevel build/object directory.
51 <p>If you obtained the sources via SVN, <var>srcdir</var> must refer to the top
52 <samp><span class="file">gcc</span></samp> directory, the one where the <samp><span class="file">MAINTAINERS</span></samp> file can be
53 found, and not its <samp><span class="file">gcc</span></samp> subdirectory, otherwise the build will fail.
55 <p>If either <var>srcdir</var> or <var>objdir</var> is located on an automounted NFS
56 file system, the shell's built-in <samp><span class="command">pwd</span></samp> command will return
57 temporary pathnames. Using these can lead to various sorts of build
58 problems. To avoid this issue, set the <samp><span class="env">PWDCMD</span></samp> environment
59 variable to an automounter-aware <samp><span class="command">pwd</span></samp> command, e.g.,
60 <samp><span class="command">pawd</span></samp> or ‘<samp><span class="samp">amq -w</span></samp>’, during the configuration and build
63 <p>First, we <strong>highly</strong> recommend that GCC be built into a
64 separate directory from the sources which does <strong>not</strong> reside
65 within the source tree. This is how we generally build GCC; building
66 where <var>srcdir</var> == <var>objdir</var> should still work, but doesn't
67 get extensive testing; building where <var>objdir</var> is a subdirectory
68 of <var>srcdir</var> is unsupported.
70 <p>If you have previously built GCC in the same directory for a
71 different target machine, do ‘<samp><span class="samp">make distclean</span></samp>’ to delete all files
72 that might be invalid. One of the files this deletes is <samp><span class="file">Makefile</span></samp>;
73 if ‘<samp><span class="samp">make distclean</span></samp>’ complains that <samp><span class="file">Makefile</span></samp> does not exist
74 or issues a message like “don't know how to make distclean” it probably
75 means that the directory is already suitably clean. However, with the
76 recommended method of building in a separate <var>objdir</var>, you should
77 simply use a different <var>objdir</var> for each target.
79 <p>Second, when configuring a native system, either <samp><span class="command">cc</span></samp> or
80 <samp><span class="command">gcc</span></samp> must be in your path or you must set <samp><span class="env">CC</span></samp> in
81 your environment before running configure. Otherwise the configuration
86 <pre class="smallexample"> % mkdir <var>objdir</var>
87 % cd <var>objdir</var>
88 % <var>srcdir</var>/configure [<var>options</var>] [<var>target</var>]
90 <h3 class="heading"><a name="TOC0"></a>Distributor options</h3>
92 <p>If you will be distributing binary versions of GCC, with modifications
93 to the source code, you should use the options described in this
94 section to make clear that your version contains modifications.
97 <dt><code>--with-pkgversion=</code><var>version</var><dd>Specify a string that identifies your package. You may wish
98 to include a build number or build date. This version string will be
99 included in the output of <samp><span class="command">gcc --version</span></samp>. This suffix does
100 not replace the default version string, only the ‘<samp><span class="samp">GCC</span></samp>’ part.
102 <p>The default value is ‘<samp><span class="samp">GCC</span></samp>’.
104 <br><dt><code>--with-bugurl=</code><var>url</var><dd>Specify the URL that users should visit if they wish to report a bug.
105 You are of course welcome to forward bugs reported to you to the FSF,
106 if you determine that they are not bugs in your modifications.
108 <p>The default value refers to the FSF's GCC bug tracker.
112 <h3 class="heading"><a name="TOC1"></a>Target specification</h3>
115 <li>GCC has code to correctly determine the correct value for <var>target</var>
116 for nearly all native systems. Therefore, we highly recommend you do
117 not provide a configure target when configuring a native compiler.
119 <li><var>target</var> must be specified as <samp><span class="option">--target=</span><var>target</var></samp>
120 when configuring a cross compiler; examples of valid targets would be
121 m68k-elf, sh-elf, etc.
123 <li>Specifying just <var>target</var> instead of <samp><span class="option">--target=</span><var>target</var></samp>
124 implies that the host defaults to <var>target</var>.
127 <h3 class="heading"><a name="TOC2"></a>Options specification</h3>
129 <p>Use <var>options</var> to override several configure time options for
130 GCC. A list of supported <var>options</var> follows; ‘<samp><span class="samp">configure
131 --help</span></samp>’ may list other options, but those not listed below may not
132 work and should not normally be used.
134 <p>Note that each <samp><span class="option">--enable</span></samp> option has a corresponding
135 <samp><span class="option">--disable</span></samp> option and that each <samp><span class="option">--with</span></samp> option has a
136 corresponding <samp><span class="option">--without</span></samp> option.
139 <dt><code>--prefix=</code><var>dirname</var><dd>Specify the toplevel installation
140 directory. This is the recommended way to install the tools into a directory
141 other than the default. The toplevel installation directory defaults to
142 <samp><span class="file">/usr/local</span></samp>.
144 <p>We <strong>highly</strong> recommend against <var>dirname</var> being the same or a
145 subdirectory of <var>objdir</var> or vice versa. If specifying a directory
146 beneath a user's home directory tree, some shells will not expand
147 <var>dirname</var> correctly if it contains the ‘<samp><span class="samp">~</span></samp>’ metacharacter; use
148 <samp><span class="env">$HOME</span></samp> instead.
150 <p>The following standard <samp><span class="command">autoconf</span></samp> options are supported. Normally you
151 should not need to use these options.
153 <dt><code>--exec-prefix=</code><var>dirname</var><dd>Specify the toplevel installation directory for architecture-dependent
154 files. The default is <samp><var>prefix</var></samp>.
156 <br><dt><code>--bindir=</code><var>dirname</var><dd>Specify the installation directory for the executables called by users
157 (such as <samp><span class="command">gcc</span></samp> and <samp><span class="command">g++</span></samp>). The default is
158 <samp><var>exec-prefix</var><span class="file">/bin</span></samp>.
160 <br><dt><code>--libdir=</code><var>dirname</var><dd>Specify the installation directory for object code libraries and
161 internal data files of GCC. The default is <samp><var>exec-prefix</var><span class="file">/lib</span></samp>.
163 <br><dt><code>--libexecdir=</code><var>dirname</var><dd>Specify the installation directory for internal executables of GCC.
164 The default is <samp><var>exec-prefix</var><span class="file">/libexec</span></samp>.
166 <br><dt><code>--with-slibdir=</code><var>dirname</var><dd>Specify the installation directory for the shared libgcc library. The
167 default is <samp><var>libdir</var></samp>.
169 <br><dt><code>--datarootdir=</code><var>dirname</var><dd>Specify the root of the directory tree for read-only architecture-independent
170 data files referenced by GCC. The default is <samp><var>prefix</var><span class="file">/share</span></samp>.
172 <br><dt><code>--infodir=</code><var>dirname</var><dd>Specify the installation directory for documentation in info format.
173 The default is <samp><var>datarootdir</var><span class="file">/info</span></samp>.
175 <br><dt><code>--datadir=</code><var>dirname</var><dd>Specify the installation directory for some architecture-independent
176 data files referenced by GCC. The default is <samp><var>datarootdir</var></samp>.
178 <br><dt><code>--docdir=</code><var>dirname</var><dd>Specify the installation directory for documentation files (other
179 than Info) for GCC. The default is <samp><var>datarootdir</var><span class="file">/doc</span></samp>.
181 <br><dt><code>--htmldir=</code><var>dirname</var><dd>Specify the installation directory for HTML documentation files.
182 The default is <samp><var>docdir</var></samp>.
184 <br><dt><code>--pdfdir=</code><var>dirname</var><dd>Specify the installation directory for PDF documentation files.
185 The default is <samp><var>docdir</var></samp>.
187 <br><dt><code>--mandir=</code><var>dirname</var><dd>Specify the installation directory for manual pages. The default is
188 <samp><var>datarootdir</var><span class="file">/man</span></samp>. (Note that the manual pages are only extracts
189 from the full GCC manuals, which are provided in Texinfo format. The manpages
190 are derived by an automatic conversion process from parts of the full
193 <br><dt><code>--with-gxx-include-dir=</code><var>dirname</var><dd>Specify
194 the installation directory for G++ header files. The default depends
195 on other configuration options, and differs between cross and native
198 <br><dt><code>--with-specs=</code><var>specs</var><dd>Specify additional command line driver SPECS.
199 This can be useful if you need to turn on a non-standard feature by
200 default without modifying the compiler's source code, for instance
201 <samp><span class="option">--with-specs=%{!fcommon:%{!fno-common:-fno-common}}</span></samp>.
202 See “Spec Files” in the main manual
206 <br><dt><code>--program-prefix=</code><var>prefix</var><dd>GCC supports some transformations of the names of its programs when
207 installing them. This option prepends <var>prefix</var> to the names of
208 programs to install in <var>bindir</var> (see above). For example, specifying
209 <samp><span class="option">--program-prefix=foo-</span></samp> would result in ‘<samp><span class="samp">gcc</span></samp>’
210 being installed as <samp><span class="file">/usr/local/bin/foo-gcc</span></samp>.
212 <br><dt><code>--program-suffix=</code><var>suffix</var><dd>Appends <var>suffix</var> to the names of programs to install in <var>bindir</var>
213 (see above). For example, specifying <samp><span class="option">--program-suffix=-3.1</span></samp>
214 would result in ‘<samp><span class="samp">gcc</span></samp>’ being installed as
215 <samp><span class="file">/usr/local/bin/gcc-3.1</span></samp>.
217 <br><dt><code>--program-transform-name=</code><var>pattern</var><dd>Applies the ‘<samp><span class="samp">sed</span></samp>’ script <var>pattern</var> to be applied to the names
218 of programs to install in <var>bindir</var> (see above). <var>pattern</var> has to
219 consist of one or more basic ‘<samp><span class="samp">sed</span></samp>’ editing commands, separated by
220 semicolons. For example, if you want the ‘<samp><span class="samp">gcc</span></samp>’ program name to be
221 transformed to the installed program <samp><span class="file">/usr/local/bin/myowngcc</span></samp> and
222 the ‘<samp><span class="samp">g++</span></samp>’ program name to be transformed to
223 <samp><span class="file">/usr/local/bin/gspecial++</span></samp> without changing other program names,
224 you could use the pattern
225 <samp><span class="option">--program-transform-name='s/^gcc$/myowngcc/; s/^g++$/gspecial++/'</span></samp>
226 to achieve this effect.
228 <p>All three options can be combined and used together, resulting in more
229 complex conversion patterns. As a basic rule, <var>prefix</var> (and
230 <var>suffix</var>) are prepended (appended) before further transformations
231 can happen with a special transformation script <var>pattern</var>.
233 <p>As currently implemented, this option only takes effect for native
234 builds; cross compiler binaries' names are not transformed even when a
235 transformation is explicitly asked for by one of these options.
237 <p>For native builds, some of the installed programs are also installed
238 with the target alias in front of their name, as in
239 ‘<samp><span class="samp">i686-pc-linux-gnu-gcc</span></samp>’. All of the above transformations happen
240 before the target alias is prepended to the name—so, specifying
241 <samp><span class="option">--program-prefix=foo-</span></samp> and <samp><span class="option">program-suffix=-3.1</span></samp>, the
242 resulting binary would be installed as
243 <samp><span class="file">/usr/local/bin/i686-pc-linux-gnu-foo-gcc-3.1</span></samp>.
245 <p>As a last shortcoming, none of the installed Ada programs are
246 transformed yet, which will be fixed in some time.
248 <br><dt><code>--with-local-prefix=</code><var>dirname</var><dd>Specify the
249 installation directory for local include files. The default is
250 <samp><span class="file">/usr/local</span></samp>. Specify this option if you want the compiler to
251 search directory <samp><var>dirname</var><span class="file">/include</span></samp> for locally installed
252 header files <em>instead</em> of <samp><span class="file">/usr/local/include</span></samp>.
254 <p>You should specify <samp><span class="option">--with-local-prefix</span></samp> <strong>only</strong> if your
255 site has a different convention (not <samp><span class="file">/usr/local</span></samp>) for where to put
258 <p>The default value for <samp><span class="option">--with-local-prefix</span></samp> is <samp><span class="file">/usr/local</span></samp>
259 regardless of the value of <samp><span class="option">--prefix</span></samp>. Specifying
260 <samp><span class="option">--prefix</span></samp> has no effect on which directory GCC searches for
261 local header files. This may seem counterintuitive, but actually it is
264 <p>The purpose of <samp><span class="option">--prefix</span></samp> is to specify where to <em>install
265 GCC</em>. The local header files in <samp><span class="file">/usr/local/include</span></samp>—if you put
266 any in that directory—are not part of GCC. They are part of other
267 programs—perhaps many others. (GCC installs its own header files in
268 another directory which is based on the <samp><span class="option">--prefix</span></samp> value.)
270 <p>Both the local-prefix include directory and the GCC-prefix include
271 directory are part of GCC's “system include” directories. Although these
272 two directories are not fixed, they need to be searched in the proper
273 order for the correct processing of the include_next directive. The
274 local-prefix include directory is searched before the GCC-prefix
275 include directory. Another characteristic of system include directories
276 is that pedantic warnings are turned off for headers in these directories.
278 <p>Some autoconf macros add <samp><span class="option">-I </span><var>directory</var></samp> options to the
279 compiler command line, to ensure that directories containing installed
280 packages' headers are searched. When <var>directory</var> is one of GCC's
281 system include directories, GCC will ignore the option so that system
282 directories continue to be processed in the correct order. This
283 may result in a search order different from what was specified but the
284 directory will still be searched.
286 <p>GCC automatically searches for ordinary libraries using
287 <samp><span class="env">GCC_EXEC_PREFIX</span></samp>. Thus, when the same installation prefix is
288 used for both GCC and packages, GCC will automatically search for
289 both headers and libraries. This provides a configuration that is
290 easy to use. GCC behaves in a manner similar to that when it is
291 installed as a system compiler in <samp><span class="file">/usr</span></samp>.
293 <p>Sites that need to install multiple versions of GCC may not want to
294 use the above simple configuration. It is possible to use the
295 <samp><span class="option">--program-prefix</span></samp>, <samp><span class="option">--program-suffix</span></samp> and
296 <samp><span class="option">--program-transform-name</span></samp> options to install multiple versions
297 into a single directory, but it may be simpler to use different prefixes
298 and the <samp><span class="option">--with-local-prefix</span></samp> option to specify the location of the
299 site-specific files for each version. It will then be necessary for
300 users to specify explicitly the location of local site libraries
301 (e.g., with <samp><span class="env">LIBRARY_PATH</span></samp>).
303 <p>The same value can be used for both <samp><span class="option">--with-local-prefix</span></samp> and
304 <samp><span class="option">--prefix</span></samp> provided it is not <samp><span class="file">/usr</span></samp>. This can be used
305 to avoid the default search of <samp><span class="file">/usr/local/include</span></samp>.
307 <p><strong>Do not</strong> specify <samp><span class="file">/usr</span></samp> as the <samp><span class="option">--with-local-prefix</span></samp>!
308 The directory you use for <samp><span class="option">--with-local-prefix</span></samp> <strong>must not</strong>
309 contain any of the system's standard header files. If it did contain
310 them, certain programs would be miscompiled (including GNU Emacs, on
311 certain targets), because this would override and nullify the header
312 file corrections made by the <samp><span class="command">fixincludes</span></samp> script.
314 <p>Indications are that people who use this option use it based on mistaken
315 ideas of what it is for. People use it as if it specified where to
316 install part of GCC. Perhaps they make this assumption because
317 installing GCC creates the directory.
319 <br><dt><code>--with-native-system-header-dir=</code><var>dirname</var><dd>Specifies that <var>dirname</var> is the directory that contains native system
320 header files, rather than <samp><span class="file">/usr/include</span></samp>. This option is most useful
321 if you are creating a compiler that should be isolated from the system
322 as much as possible. It is most commonly used with the
323 <samp><span class="option">--with-sysroot</span></samp> option and will cause GCC to search
324 <var>dirname</var> inside the system root specified by that option.
326 <br><dt><code>--enable-shared[=</code><var>package</var><code>[,...]]</code><dd>Build shared versions of libraries, if shared libraries are supported on
327 the target platform. Unlike GCC 2.95.x and earlier, shared libraries
328 are enabled by default on all platforms that support shared libraries.
330 <p>If a list of packages is given as an argument, build shared libraries
331 only for the listed packages. For other packages, only static libraries
332 will be built. Package names currently recognized in the GCC tree are
333 ‘<samp><span class="samp">libgcc</span></samp>’ (also known as ‘<samp><span class="samp">gcc</span></samp>’), ‘<samp><span class="samp">libstdc++</span></samp>’ (not
334 ‘<samp><span class="samp">libstdc++-v3</span></samp>’), ‘<samp><span class="samp">libffi</span></samp>’, ‘<samp><span class="samp">zlib</span></samp>’, ‘<samp><span class="samp">boehm-gc</span></samp>’,
335 ‘<samp><span class="samp">ada</span></samp>’, ‘<samp><span class="samp">libada</span></samp>’, ‘<samp><span class="samp">libjava</span></samp>’, ‘<samp><span class="samp">libgo</span></samp>’, and ‘<samp><span class="samp">libobjc</span></samp>’.
336 Note ‘<samp><span class="samp">libiberty</span></samp>’ does not support shared libraries at all.
338 <p>Use <samp><span class="option">--disable-shared</span></samp> to build only static libraries. Note that
339 <samp><span class="option">--disable-shared</span></samp> does not accept a list of package names as
340 argument, only <samp><span class="option">--enable-shared</span></samp> does.
342 <br><dt><code><a name="with_002dgnu_002das"></a>--with-gnu-as</code><dd>Specify that the compiler should assume that the
343 assembler it finds is the GNU assembler. However, this does not modify
344 the rules to find an assembler and will result in confusion if the
345 assembler found is not actually the GNU assembler. (Confusion may also
346 result if the compiler finds the GNU assembler but has not been
347 configured with <samp><span class="option">--with-gnu-as</span></samp>.) If you have more than one
348 assembler installed on your system, you may want to use this option in
349 connection with <samp><span class="option">--with-as=</span><var>pathname</var></samp> or
350 <samp><span class="option">--with-build-time-tools=</span><var>pathname</var></samp>.
352 <p>The following systems are the only ones where it makes a difference
353 whether you use the GNU assembler. On any other system,
354 <samp><span class="option">--with-gnu-as</span></samp> has no effect.
357 <li>‘<samp><span class="samp">hppa1.0-</span><var>any</var><span class="samp">-</span><var>any</var></samp>’
358 <li>‘<samp><span class="samp">hppa1.1-</span><var>any</var><span class="samp">-</span><var>any</var></samp>’
359 <li>‘<samp><span class="samp">sparc-sun-solaris2.</span><var>any</var></samp>’
360 <li>‘<samp><span class="samp">sparc64-</span><var>any</var><span class="samp">-solaris2.</span><var>any</var></samp>’
363 <br><dt><code><a name="with_002das"></a>--with-as=</code><var>pathname</var><dd>Specify that the compiler should use the assembler pointed to by
364 <var>pathname</var>, rather than the one found by the standard rules to find
365 an assembler, which are:
367 <li>Unless GCC is being built with a cross compiler, check the
368 <samp><var>libexec</var><span class="file">/gcc/</span><var>target</var><span class="file">/</span><var>version</var></samp> directory.
369 <var>libexec</var> defaults to <samp><var>exec-prefix</var><span class="file">/libexec</span></samp>;
370 <var>exec-prefix</var> defaults to <var>prefix</var>, which
371 defaults to <samp><span class="file">/usr/local</span></samp> unless overridden by the
372 <samp><span class="option">--prefix=</span><var>pathname</var></samp> switch described above. <var>target</var>
373 is the target system triple, such as ‘<samp><span class="samp">sparc-sun-solaris2.7</span></samp>’, and
374 <var>version</var> denotes the GCC version, such as 3.0.
376 <li>If the target system is the same that you are building on, check
377 operating system specific directories (e.g. <samp><span class="file">/usr/ccs/bin</span></samp> on
380 <li>Check in the <samp><span class="env">PATH</span></samp> for a tool whose name is prefixed by the
381 target system triple.
383 <li>Check in the <samp><span class="env">PATH</span></samp> for a tool whose name is not prefixed by the
384 target system triple, if the host and target system triple are
385 the same (in other words, we use a host tool if it can be used for
389 <p>You may want to use <samp><span class="option">--with-as</span></samp> if no assembler
390 is installed in the directories listed above, or if you have multiple
391 assemblers installed and want to choose one that is not found by the
394 <br><dt><code><a name="with_002dgnu_002dld"></a>--with-gnu-ld</code><dd>Same as <a href="#with-gnu-as"><samp><span class="option">--with-gnu-as</span></samp></a>
397 <br><dt><code>--with-ld=</code><var>pathname</var><dd>Same as <a href="#with-as"><samp><span class="option">--with-as</span></samp></a>
400 <br><dt><code>--with-stabs</code><dd>Specify that stabs debugging
401 information should be used instead of whatever format the host normally
402 uses. Normally GCC uses the same debug format as the host system.
404 <p>On MIPS based systems and on Alphas, you must specify whether you want
405 GCC to create the normal ECOFF debugging format, or to use BSD-style
406 stabs passed through the ECOFF symbol table. The normal ECOFF debug
407 format cannot fully handle languages other than C. BSD stabs format can
408 handle other languages, but it only works with the GNU debugger GDB.
410 <p>Normally, GCC uses the ECOFF debugging format by default; if you
411 prefer BSD stabs, specify <samp><span class="option">--with-stabs</span></samp> when you configure GCC.
413 <p>No matter which default you choose when you configure GCC, the user
414 can use the <samp><span class="option">-gcoff</span></samp> and <samp><span class="option">-gstabs+</span></samp> options to specify explicitly
415 the debug format for a particular compilation.
417 <p><samp><span class="option">--with-stabs</span></samp> is meaningful on the ISC system on the 386, also, if
418 <samp><span class="option">--with-gas</span></samp> is used. It selects use of stabs debugging
419 information embedded in COFF output. This kind of debugging information
420 supports C++ well; ordinary COFF debugging information does not.
422 <p><samp><span class="option">--with-stabs</span></samp> is also meaningful on 386 systems running SVR4. It
423 selects use of stabs debugging information embedded in ELF output. The
424 C++ compiler currently (2.6.0) does not support the DWARF debugging
425 information normally used on 386 SVR4 platforms; stabs provide a
426 workable alternative. This requires gas and gdb, as the normal SVR4
427 tools can not generate or interpret stabs.
429 <br><dt><code>--with-tls=</code><var>dialect</var><dd>Specify the default TLS dialect, for systems were there is a choice.
430 For ARM targets, possible values for <var>dialect</var> are <code>gnu</code> or
431 <code>gnu2</code>, which select between the original GNU dialect and the GNU TLS
432 descriptor-based dialect.
434 <br><dt><code>--enable-multiarch</code><dd>Specify whether to enable or disable multiarch support. The default is
435 to check for glibc start files in a multiarch location, and enable it
436 if the files are found. The auto detection is enabled for native builds,
437 and for cross builds configured with <samp><span class="option">--with-sysroot</span></samp>, and without
438 <samp><span class="option">--with-native-system-header-dir</span></samp>.
439 More documentation about multiarch can be found at
440 <a href="http://wiki.debian.org/Multiarch">http://wiki.debian.org/Multiarch</a>.
442 <br><dt><code>--disable-multilib</code><dd>Specify that multiple target
443 libraries to support different target variants, calling
444 conventions, etc. should not be built. The default is to build a
445 predefined set of them.
447 <p>Some targets provide finer-grained control over which multilibs are built
448 (e.g., <samp><span class="option">--disable-softfloat</span></samp>):
450 <dt><code>arm-*-*</code><dd>fpu, 26bit, underscore, interwork, biendian, nofmult.
452 <br><dt><code>m68*-*-*</code><dd>softfloat, m68881, m68000, m68020.
454 <br><dt><code>mips*-*-*</code><dd>single-float, biendian, softfloat.
456 <br><dt><code>powerpc*-*-*, rs6000*-*-*</code><dd>aix64, pthread, softfloat, powercpu, powerpccpu, powerpcos, biendian,
461 <br><dt><code>--with-multilib-list=</code><var>list</var><dt><code>--without-multilib-list</code><dd>Specify what multilibs to build.
462 Currently only implemented for sh*-*-* and x86-64-*-linux*.
465 <dt><code>sh*-*-*</code><dd><var>list</var> is a comma separated list of CPU names. These must be of the
466 form <code>sh*</code> or <code>m*</code> (in which case they match the compiler option
467 for that processor). The list should not contain any endian options -
468 these are handled by <samp><span class="option">--with-endian</span></samp>.
470 <p>If <var>list</var> is empty, then there will be no multilibs for extra
471 processors. The multilib for the secondary endian remains enabled.
473 <p>As a special case, if an entry in the list starts with a <code>!</code>
474 (exclamation point), then it is added to the list of excluded multilibs.
475 Entries of this sort should be compatible with ‘<samp><span class="samp">MULTILIB_EXCLUDES</span></samp>’
476 (once the leading <code>!</code> has been stripped).
478 <p>If <samp><span class="option">--with-multilib-list</span></samp> is not given, then a default set of
479 multilibs is selected based on the value of <samp><span class="option">--target</span></samp>. This is
480 usually the complete set of libraries, but some targets imply a more
483 <p>Example 1: to configure a compiler for SH4A only, but supporting both
484 endians, with little endian being the default:
485 <pre class="smallexample"> --with-cpu=sh4a --with-endian=little,big --with-multilib-list=
487 <p>Example 2: to configure a compiler for both SH4A and SH4AL-DSP, but with
488 only little endian SH4AL:
489 <pre class="smallexample"> --with-cpu=sh4a --with-endian=little,big \
490 --with-multilib-list=sh4al,!mb/m4al
492 <br><dt><code>x86-64-*-linux*</code><dd><var>list</var> is a comma separated list of <code>m32</code>, <code>m64</code> and
493 <code>mx32</code> to enable 32-bit, 64-bit and x32 run-time libraries,
494 respectively. If <var>list</var> is empty, then there will be no multilibs
495 and only the default run-time library will be enabled.
497 <p>If <samp><span class="option">--with-multilib-list</span></samp> is not given, then only 32-bit and
498 64-bit run-time libraries will be enabled.
501 <br><dt><code>--with-endian=</code><var>endians</var><dd>Specify what endians to use.
502 Currently only implemented for sh*-*-*.
504 <p><var>endians</var> may be one of the following:
506 <dt><code>big</code><dd>Use big endian exclusively.
507 <br><dt><code>little</code><dd>Use little endian exclusively.
508 <br><dt><code>big,little</code><dd>Use big endian by default. Provide a multilib for little endian.
509 <br><dt><code>little,big</code><dd>Use little endian by default. Provide a multilib for big endian.
512 <br><dt><code>--enable-threads</code><dd>Specify that the target
513 supports threads. This affects the Objective-C compiler and runtime
514 library, and exception handling for other languages like C++ and Java.
515 On some systems, this is the default.
517 <p>In general, the best (and, in many cases, the only known) threading
518 model available will be configured for use. Beware that on some
519 systems, GCC has not been taught what threading models are generally
520 available for the system. In this case, <samp><span class="option">--enable-threads</span></samp> is an
521 alias for <samp><span class="option">--enable-threads=single</span></samp>.
523 <br><dt><code>--disable-threads</code><dd>Specify that threading support should be disabled for the system.
524 This is an alias for <samp><span class="option">--enable-threads=single</span></samp>.
526 <br><dt><code>--enable-threads=</code><var>lib</var><dd>Specify that
527 <var>lib</var> is the thread support library. This affects the Objective-C
528 compiler and runtime library, and exception handling for other languages
529 like C++ and Java. The possibilities for <var>lib</var> are:
532 <dt><code>aix</code><dd>AIX thread support.
533 <br><dt><code>dce</code><dd>DCE thread support.
534 <br><dt><code>lynx</code><dd>LynxOS thread support.
535 <br><dt><code>mipssde</code><dd>MIPS SDE thread support.
536 <br><dt><code>no</code><dd>This is an alias for ‘<samp><span class="samp">single</span></samp>’.
537 <br><dt><code>posix</code><dd>Generic POSIX/Unix98 thread support.
538 <br><dt><code>rtems</code><dd>RTEMS thread support.
539 <br><dt><code>single</code><dd>Disable thread support, should work for all platforms.
540 <br><dt><code>tpf</code><dd>TPF thread support.
541 <br><dt><code>vxworks</code><dd>VxWorks thread support.
542 <br><dt><code>win32</code><dd>Microsoft Win32 API thread support.
545 <br><dt><code>--enable-tls</code><dd>Specify that the target supports TLS (Thread Local Storage). Usually
546 configure can correctly determine if TLS is supported. In cases where
547 it guesses incorrectly, TLS can be explicitly enabled or disabled with
548 <samp><span class="option">--enable-tls</span></samp> or <samp><span class="option">--disable-tls</span></samp>. This can happen if
549 the assembler supports TLS but the C library does not, or if the
550 assumptions made by the configure test are incorrect.
552 <br><dt><code>--disable-tls</code><dd>Specify that the target does not support TLS.
553 This is an alias for <samp><span class="option">--enable-tls=no</span></samp>.
555 <br><dt><code>--with-cpu=</code><var>cpu</var><dt><code>--with-cpu-32=</code><var>cpu</var><dt><code>--with-cpu-64=</code><var>cpu</var><dd>Specify which cpu variant the compiler should generate code for by default.
556 <var>cpu</var> will be used as the default value of the <samp><span class="option">-mcpu=</span></samp> switch.
557 This option is only supported on some targets, including ARM, i386, M68k,
558 PowerPC, and SPARC. The <samp><span class="option">--with-cpu-32</span></samp> and
559 <samp><span class="option">--with-cpu-64</span></samp> options specify separate default CPUs for
560 32-bit and 64-bit modes; these options are only supported for i386,
563 <br><dt><code>--with-schedule=</code><var>cpu</var><dt><code>--with-arch=</code><var>cpu</var><dt><code>--with-arch-32=</code><var>cpu</var><dt><code>--with-arch-64=</code><var>cpu</var><dt><code>--with-tune=</code><var>cpu</var><dt><code>--with-tune-32=</code><var>cpu</var><dt><code>--with-tune-64=</code><var>cpu</var><dt><code>--with-abi=</code><var>abi</var><dt><code>--with-fpu=</code><var>type</var><dt><code>--with-float=</code><var>type</var><dd>These configure options provide default values for the <samp><span class="option">-mschedule=</span></samp>,
564 <samp><span class="option">-march=</span></samp>, <samp><span class="option">-mtune=</span></samp>, <samp><span class="option">-mabi=</span></samp>, and <samp><span class="option">-mfpu=</span></samp>
565 options and for <samp><span class="option">-mhard-float</span></samp> or <samp><span class="option">-msoft-float</span></samp>. As with
566 <samp><span class="option">--with-cpu</span></samp>, which switches will be accepted and acceptable values
567 of the arguments depend on the target.
569 <br><dt><code>--with-mode=</code><var>mode</var><dd>Specify if the compiler should default to <samp><span class="option">-marm</span></samp> or <samp><span class="option">-mthumb</span></samp>.
570 This option is only supported on ARM targets.
572 <br><dt><code>--with-stack-offset=</code><var>num</var><dd>This option sets the default for the -mstack-offset=<var>num</var> option,
573 and will thus generally also control the setting of this option for
574 libraries. This option is only supported on Epiphany targets.
576 <br><dt><code>--with-fpmath=</code><var>isa</var><dd>This options sets <samp><span class="option">-mfpmath=sse</span></samp> by default and specifies the default
577 ISA for floating-point arithmetics. You can select either ‘<samp><span class="samp">sse</span></samp>’ which
578 enables <samp><span class="option">-msse2</span></samp> or ‘<samp><span class="samp">avx</span></samp>’ which enables <samp><span class="option">-mavx</span></samp> by default.
579 This option is only supported on i386 and x86-64 targets.
581 <br><dt><code>--with-divide=</code><var>type</var><dd>Specify how the compiler should generate code for checking for
582 division by zero. This option is only supported on the MIPS target.
583 The possibilities for <var>type</var> are:
585 <dt><code>traps</code><dd>Division by zero checks use conditional traps (this is the default on
586 systems that support conditional traps).
587 <br><dt><code>breaks</code><dd>Division by zero checks use the break instruction.
590 <!-- If you make -with-llsc the default for additional targets, -->
591 <!-- update the -with-llsc description in the MIPS section below. -->
592 <br><dt><code>--with-llsc</code><dd>On MIPS targets, make <samp><span class="option">-mllsc</span></samp> the default when no
593 <samp><span class="option">-mno-llsc</span></samp> option is passed. This is the default for
594 Linux-based targets, as the kernel will emulate them if the ISA does
597 <br><dt><code>--without-llsc</code><dd>On MIPS targets, make <samp><span class="option">-mno-llsc</span></samp> the default when no
598 <samp><span class="option">-mllsc</span></samp> option is passed.
600 <br><dt><code>--with-synci</code><dd>On MIPS targets, make <samp><span class="option">-msynci</span></samp> the default when no
601 <samp><span class="option">-mno-synci</span></samp> option is passed.
603 <br><dt><code>--without-synci</code><dd>On MIPS targets, make <samp><span class="option">-mno-synci</span></samp> the default when no
604 <samp><span class="option">-msynci</span></samp> option is passed. This is the default.
606 <br><dt><code>--with-mips-plt</code><dd>On MIPS targets, make use of copy relocations and PLTs.
607 These features are extensions to the traditional
608 SVR4-based MIPS ABIs and require support from GNU binutils
609 and the runtime C library.
611 <br><dt><code>--enable-__cxa_atexit</code><dd>Define if you want to use __cxa_atexit, rather than atexit, to
612 register C++ destructors for local statics and global objects.
613 This is essential for fully standards-compliant handling of
614 destructors, but requires __cxa_atexit in libc. This option is currently
615 only available on systems with GNU libc. When enabled, this will cause
616 <samp><span class="option">-fuse-cxa-atexit</span></samp> to be passed by default.
618 <br><dt><code>--enable-gnu-indirect-function</code><dd>Define if you want to enable the <code>ifunc</code> attribute. This option is
619 currently only available on systems with GNU libc on certain targets.
621 <br><dt><code>--enable-target-optspace</code><dd>Specify that target
622 libraries should be optimized for code space instead of code speed.
623 This is the default for the m32r platform.
625 <br><dt><code>--with-cpp-install-dir=</code><var>dirname</var><dd>Specify that the user visible <samp><span class="command">cpp</span></samp> program should be installed
626 in <samp><var>prefix</var><span class="file">/</span><var>dirname</var><span class="file">/cpp</span></samp>, in addition to <var>bindir</var>.
628 <br><dt><code>--enable-comdat</code><dd>Enable COMDAT group support. This is primarily used to override the
629 automatically detected value.
631 <br><dt><code>--enable-initfini-array</code><dd>Force the use of sections <code>.init_array</code> and <code>.fini_array</code>
632 (instead of <code>.init</code> and <code>.fini</code>) for constructors and
633 destructors. Option <samp><span class="option">--disable-initfini-array</span></samp> has the
634 opposite effect. If neither option is specified, the configure script
635 will try to guess whether the <code>.init_array</code> and
636 <code>.fini_array</code> sections are supported and, if they are, use them.
638 <br><dt><code>--enable-maintainer-mode</code><dd>The build rules that regenerate the Autoconf and Automake output files as
639 well as the GCC master message catalog <samp><span class="file">gcc.pot</span></samp> are normally
640 disabled. This is because it can only be rebuilt if the complete source
641 tree is present. If you have changed the sources and want to rebuild the
642 catalog, configuring with <samp><span class="option">--enable-maintainer-mode</span></samp> will enable
643 this. Note that you need a recent version of the <code>gettext</code> tools
646 <br><dt><code>--disable-bootstrap</code><dd>For a native build, the default configuration is to perform
647 a 3-stage bootstrap of the compiler when ‘<samp><span class="samp">make</span></samp>’ is invoked,
648 testing that GCC can compile itself correctly. If you want to disable
649 this process, you can configure with <samp><span class="option">--disable-bootstrap</span></samp>.
651 <br><dt><code>--enable-bootstrap</code><dd>In special cases, you may want to perform a 3-stage build
652 even if the target and host triplets are different.
653 This is possible when the host can run code compiled for
654 the target (e.g. host is i686-linux, target is i486-linux).
655 Starting from GCC 4.2, to do this you have to configure explicitly
656 with <samp><span class="option">--enable-bootstrap</span></samp>.
658 <br><dt><code>--enable-generated-files-in-srcdir</code><dd>Neither the .c and .h files that are generated from Bison and flex nor the
659 info manuals and man pages that are built from the .texi files are present
660 in the SVN development tree. When building GCC from that development tree,
661 or from one of our snapshots, those generated files are placed in your
662 build directory, which allows for the source to be in a readonly
665 <p>If you configure with <samp><span class="option">--enable-generated-files-in-srcdir</span></samp> then those
666 generated files will go into the source directory. This is mainly intended
667 for generating release or prerelease tarballs of the GCC sources, since it
668 is not a requirement that the users of source releases to have flex, Bison,
671 <br><dt><code>--enable-version-specific-runtime-libs</code><dd>Specify
672 that runtime libraries should be installed in the compiler specific
673 subdirectory (<samp><var>libdir</var><span class="file">/gcc</span></samp>) rather than the usual places. In
674 addition, ‘<samp><span class="samp">libstdc++</span></samp>’'s include files will be installed into
675 <samp><var>libdir</var></samp> unless you overruled it by using
676 <samp><span class="option">--with-gxx-include-dir=</span><var>dirname</var></samp>. Using this option is
677 particularly useful if you intend to use several versions of GCC in
678 parallel. This is currently supported by ‘<samp><span class="samp">libgfortran</span></samp>’,
679 ‘<samp><span class="samp">libjava</span></samp>’, ‘<samp><span class="samp">libmudflap</span></samp>’, ‘<samp><span class="samp">libstdc++</span></samp>’, and ‘<samp><span class="samp">libobjc</span></samp>’.
681 <br><dt><code>--enable-languages=</code><var>lang1</var><code>,</code><var>lang2</var><code>,...</code><dd>Specify that only a particular subset of compilers and
682 their runtime libraries should be built. For a list of valid values for
683 <var>langN</var> you can issue the following command in the
684 <samp><span class="file">gcc</span></samp> directory of your GCC source tree:<br>
685 <pre class="smallexample"> grep language= */config-lang.in
687 <p>Currently, you can use any of the following:
688 <code>all</code>, <code>ada</code>, <code>c</code>, <code>c++</code>, <code>fortran</code>,
689 <code>go</code>, <code>java</code>, <code>objc</code>, <code>obj-c++</code>.
690 Building the Ada compiler has special requirements, see below.
691 If you do not pass this flag, or specify the option <code>all</code>, then all
692 default languages available in the <samp><span class="file">gcc</span></samp> sub-tree will be configured.
693 Ada, Go and Objective-C++ are not default languages; the rest are.
695 <br><dt><code>--enable-stage1-languages=</code><var>lang1</var><code>,</code><var>lang2</var><code>,...</code><dd>Specify that a particular subset of compilers and their runtime
696 libraries should be built with the system C compiler during stage 1 of
697 the bootstrap process, rather than only in later stages with the
698 bootstrapped C compiler. The list of valid values is the same as for
699 <samp><span class="option">--enable-languages</span></samp>, and the option <code>all</code> will select all
700 of the languages enabled by <samp><span class="option">--enable-languages</span></samp>. This option is
701 primarily useful for GCC development; for instance, when a development
702 version of the compiler cannot bootstrap due to compiler bugs, or when
703 one is debugging front ends other than the C front end. When this
704 option is used, one can then build the target libraries for the
705 specified languages with the stage-1 compiler by using <samp><span class="command">make
706 stage1-bubble all-target</span></samp>, or run the testsuite on the stage-1 compiler
707 for the specified languages using <samp><span class="command">make stage1-start check-gcc</span></samp>.
709 <br><dt><code>--disable-libada</code><dd>Specify that the run-time libraries and tools used by GNAT should not
710 be built. This can be useful for debugging, or for compatibility with
711 previous Ada build procedures, when it was required to explicitly
712 do a ‘<samp><span class="samp">make -C gcc gnatlib_and_tools</span></samp>’.
714 <br><dt><code>--disable-libssp</code><dd>Specify that the run-time libraries for stack smashing protection
717 <br><dt><code>--disable-libquadmath</code><dd>Specify that the GCC quad-precision math library should not be built.
718 On some systems, the library is required to be linkable when building
719 the Fortran front end, unless <samp><span class="option">--disable-libquadmath-support</span></samp>
722 <br><dt><code>--disable-libquadmath-support</code><dd>Specify that the Fortran front end and <code>libgfortran</code> do not add
723 support for <code>libquadmath</code> on systems supporting it.
725 <br><dt><code>--disable-libgomp</code><dd>Specify that the run-time libraries used by GOMP should not be built.
727 <br><dt><code>--with-dwarf2</code><dd>Specify that the compiler should
728 use DWARF 2 debugging information as the default.
730 <br><dt><code>--enable-targets=all</code><dt><code>--enable-targets=</code><var>target_list</var><dd>Some GCC targets, e.g. powerpc64-linux, build bi-arch compilers.
731 These are compilers that are able to generate either 64-bit or 32-bit
732 code. Typically, the corresponding 32-bit target, e.g.
733 powerpc-linux for powerpc64-linux, only generates 32-bit code. This
734 option enables the 32-bit target to be a bi-arch compiler, which is
735 useful when you want a bi-arch compiler that defaults to 32-bit, and
736 you are building a bi-arch or multi-arch binutils in a combined tree.
737 On mips-linux, this will build a tri-arch compiler (ABI o32/n32/64),
739 Currently, this option only affects sparc-linux, powerpc-linux, x86-linux,
740 mips-linux and s390-linux.
742 <br><dt><code>--enable-secureplt</code><dd>This option enables <samp><span class="option">-msecure-plt</span></samp> by default for powerpc-linux.
743 See “RS/6000 and PowerPC Options” in the main manual
745 <br><dt><code>--enable-cld</code><dd>This option enables <samp><span class="option">-mcld</span></samp> by default for 32-bit x86 targets.
746 See “i386 and x86-64 Options” in the main manual
748 <br><dt><code>--enable-win32-registry</code><dt><code>--enable-win32-registry=</code><var>key</var><dt><code>--disable-win32-registry</code><dd>The <samp><span class="option">--enable-win32-registry</span></samp> option enables Microsoft Windows-hosted GCC
749 to look up installations paths in the registry using the following key:
751 <pre class="smallexample"> <code>HKEY_LOCAL_MACHINE\SOFTWARE\Free Software Foundation\</code><var>key</var>
753 <p><var>key</var> defaults to GCC version number, and can be overridden by the
754 <samp><span class="option">--enable-win32-registry=</span><var>key</var></samp> option. Vendors and distributors
755 who use custom installers are encouraged to provide a different key,
756 perhaps one comprised of vendor name and GCC version number, to
757 avoid conflict with existing installations. This feature is enabled
758 by default, and can be disabled by <samp><span class="option">--disable-win32-registry</span></samp>
759 option. This option has no effect on the other hosts.
761 <br><dt><code>--nfp</code><dd>Specify that the machine does not have a floating point unit. This
762 option only applies to ‘<samp><span class="samp">m68k-sun-sunos</span><var>n</var></samp>’. On any other
763 system, <samp><span class="option">--nfp</span></samp> has no effect.
765 <br><dt><code>--enable-werror</code><dt><code>--disable-werror</code><dt><code>--enable-werror=yes</code><dt><code>--enable-werror=no</code><dd>When you specify this option, it controls whether certain files in the
766 compiler are built with <samp><span class="option">-Werror</span></samp> in bootstrap stage2 and later.
767 If you don't specify it, <samp><span class="option">-Werror</span></samp> is turned on for the main
768 development trunk. However it defaults to off for release branches and
769 final releases. The specific files which get <samp><span class="option">-Werror</span></samp> are
770 controlled by the Makefiles.
772 <br><dt><code>--enable-checking</code><dt><code>--enable-checking=</code><var>list</var><dd>When you specify this option, the compiler is built to perform internal
773 consistency checks of the requested complexity. This does not change the
774 generated code, but adds error checking within the compiler. This will
775 slow down the compiler and may only work properly if you are building
776 the compiler with GCC. This is ‘<samp><span class="samp">yes</span></samp>’ by default when building
777 from SVN or snapshots, but ‘<samp><span class="samp">release</span></samp>’ for releases. The default
778 for building the stage1 compiler is ‘<samp><span class="samp">yes</span></samp>’. More control
779 over the checks may be had by specifying <var>list</var>. The categories of
780 checks available are ‘<samp><span class="samp">yes</span></samp>’ (most common checks
781 ‘<samp><span class="samp">assert,misc,tree,gc,rtlflag,runtime</span></samp>’), ‘<samp><span class="samp">no</span></samp>’ (no checks at
782 all), ‘<samp><span class="samp">all</span></samp>’ (all but ‘<samp><span class="samp">valgrind</span></samp>’), ‘<samp><span class="samp">release</span></samp>’ (cheapest
783 checks ‘<samp><span class="samp">assert,runtime</span></samp>’) or ‘<samp><span class="samp">none</span></samp>’ (same as ‘<samp><span class="samp">no</span></samp>’).
784 Individual checks can be enabled with these flags ‘<samp><span class="samp">assert</span></samp>’,
785 ‘<samp><span class="samp">df</span></samp>’, ‘<samp><span class="samp">fold</span></samp>’, ‘<samp><span class="samp">gc</span></samp>’, ‘<samp><span class="samp">gcac</span></samp>’ ‘<samp><span class="samp">misc</span></samp>’, ‘<samp><span class="samp">rtl</span></samp>’,
786 ‘<samp><span class="samp">rtlflag</span></samp>’, ‘<samp><span class="samp">runtime</span></samp>’, ‘<samp><span class="samp">tree</span></samp>’, and ‘<samp><span class="samp">valgrind</span></samp>’.
788 <p>The ‘<samp><span class="samp">valgrind</span></samp>’ check requires the external <samp><span class="command">valgrind</span></samp>
789 simulator, available from <a href="http://valgrind.org/">http://valgrind.org/</a>. The
790 ‘<samp><span class="samp">df</span></samp>’, ‘<samp><span class="samp">rtl</span></samp>’, ‘<samp><span class="samp">gcac</span></samp>’ and ‘<samp><span class="samp">valgrind</span></samp>’ checks are very expensive.
791 To disable all checking, ‘<samp><span class="samp">--disable-checking</span></samp>’ or
792 ‘<samp><span class="samp">--enable-checking=none</span></samp>’ must be explicitly requested. Disabling
793 assertions will make the compiler and runtime slightly faster but
794 increase the risk of undetected internal errors causing wrong code to be
797 <br><dt><code>--disable-stage1-checking</code><dt><code>--enable-stage1-checking</code><dt><code>--enable-stage1-checking=</code><var>list</var><dd>If no <samp><span class="option">--enable-checking</span></samp> option is specified the stage1
798 compiler will be built with ‘<samp><span class="samp">yes</span></samp>’ checking enabled, otherwise
799 the stage1 checking flags are the same as specified by
800 <samp><span class="option">--enable-checking</span></samp>. To build the stage1 compiler with
801 different checking options use <samp><span class="option">--enable-stage1-checking</span></samp>.
802 The list of checking options is the same as for <samp><span class="option">--enable-checking</span></samp>.
803 If your system is too slow or too small to bootstrap a released compiler
804 with checking for stage1 enabled, you can use ‘<samp><span class="samp">--disable-stage1-checking</span></samp>’
805 to disable checking for the stage1 compiler.
807 <br><dt><code>--enable-coverage</code><dt><code>--enable-coverage=</code><var>level</var><dd>With this option, the compiler is built to collect self coverage
808 information, every time it is run. This is for internal development
809 purposes, and only works when the compiler is being built with gcc. The
810 <var>level</var> argument controls whether the compiler is built optimized or
811 not, values are ‘<samp><span class="samp">opt</span></samp>’ and ‘<samp><span class="samp">noopt</span></samp>’. For coverage analysis you
812 want to disable optimization, for performance analysis you want to
813 enable optimization. When coverage is enabled, the default level is
814 without optimization.
816 <br><dt><code>--enable-gather-detailed-mem-stats</code><dd>When this option is specified more detailed information on memory
817 allocation is gathered. This information is printed when using
818 <samp><span class="option">-fmem-report</span></samp>.
820 <br><dt><code>--enable-nls</code><dt><code>--disable-nls</code><dd>The <samp><span class="option">--enable-nls</span></samp> option enables Native Language Support (NLS),
821 which lets GCC output diagnostics in languages other than American
822 English. Native Language Support is enabled by default if not doing a
823 canadian cross build. The <samp><span class="option">--disable-nls</span></samp> option disables NLS.
825 <br><dt><code>--with-included-gettext</code><dd>If NLS is enabled, the <samp><span class="option">--with-included-gettext</span></samp> option causes the build
826 procedure to prefer its copy of GNU <samp><span class="command">gettext</span></samp>.
828 <br><dt><code>--with-catgets</code><dd>If NLS is enabled, and if the host lacks <code>gettext</code> but has the
829 inferior <code>catgets</code> interface, the GCC build procedure normally
830 ignores <code>catgets</code> and instead uses GCC's copy of the GNU
831 <code>gettext</code> library. The <samp><span class="option">--with-catgets</span></samp> option causes the
832 build procedure to use the host's <code>catgets</code> in this situation.
834 <br><dt><code>--with-libiconv-prefix=</code><var>dir</var><dd>Search for libiconv header files in <samp><var>dir</var><span class="file">/include</span></samp> and
835 libiconv library files in <samp><var>dir</var><span class="file">/lib</span></samp>.
837 <br><dt><code>--enable-obsolete</code><dd>Enable configuration for an obsoleted system. If you attempt to
838 configure GCC for a system (build, host, or target) which has been
839 obsoleted, and you do not specify this flag, configure will halt with an
842 <p>All support for systems which have been obsoleted in one release of GCC
843 is removed entirely in the next major release, unless someone steps
844 forward to maintain the port.
846 <br><dt><code>--enable-decimal-float</code><dt><code>--enable-decimal-float=yes</code><dt><code>--enable-decimal-float=no</code><dt><code>--enable-decimal-float=bid</code><dt><code>--enable-decimal-float=dpd</code><dt><code>--disable-decimal-float</code><dd>Enable (or disable) support for the C decimal floating point extension
847 that is in the IEEE 754-2008 standard. This is enabled by default only
848 on PowerPC, i386, and x86_64 GNU/Linux systems. Other systems may also
849 support it, but require the user to specifically enable it. You can
850 optionally control which decimal floating point format is used (either
851 ‘<samp><span class="samp">bid</span></samp>’ or ‘<samp><span class="samp">dpd</span></samp>’). The ‘<samp><span class="samp">bid</span></samp>’ (binary integer decimal)
852 format is default on i386 and x86_64 systems, and the ‘<samp><span class="samp">dpd</span></samp>’
853 (densely packed decimal) format is default on PowerPC systems.
855 <br><dt><code>--enable-fixed-point</code><dt><code>--disable-fixed-point</code><dd>Enable (or disable) support for C fixed-point arithmetic.
856 This option is enabled by default for some targets (such as MIPS) which
857 have hardware-support for fixed-point operations. On other targets, you
858 may enable this option manually.
860 <br><dt><code>--with-long-double-128</code><dd>Specify if <code>long double</code> type should be 128-bit by default on selected
861 GNU/Linux architectures. If using <code>--without-long-double-128</code>,
862 <code>long double</code> will be by default 64-bit, the same as <code>double</code> type.
863 When neither of these configure options are used, the default will be
864 128-bit <code>long double</code> when built against GNU C Library 2.4 and later,
865 64-bit <code>long double</code> otherwise.
867 <br><dt><code>--with-gmp=</code><var>pathname</var><dt><code>--with-gmp-include=</code><var>pathname</var><dt><code>--with-gmp-lib=</code><var>pathname</var><dt><code>--with-mpfr=</code><var>pathname</var><dt><code>--with-mpfr-include=</code><var>pathname</var><dt><code>--with-mpfr-lib=</code><var>pathname</var><dt><code>--with-mpc=</code><var>pathname</var><dt><code>--with-mpc-include=</code><var>pathname</var><dt><code>--with-mpc-lib=</code><var>pathname</var><dd>If you want to build GCC but do not have the GMP library, the MPFR
868 library and/or the MPC library installed in a standard location and
869 do not have their sources present in the GCC source tree then you
870 can explicitly specify the directory where they are installed
871 (‘<samp><span class="samp">--with-gmp=</span><var>gmpinstalldir</var></samp>’,
872 ‘<samp><span class="samp">--with-mpfr=</span><var>mpfrinstalldir</var></samp>’,
873 ‘<samp><span class="samp">--with-mpc=</span><var>mpcinstalldir</var></samp>’). The
874 <samp><span class="option">--with-gmp=</span><var>gmpinstalldir</var></samp> option is shorthand for
875 <samp><span class="option">--with-gmp-lib=</span><var>gmpinstalldir</var><span class="option">/lib</span></samp> and
876 <samp><span class="option">--with-gmp-include=</span><var>gmpinstalldir</var><span class="option">/include</span></samp>. Likewise the
877 <samp><span class="option">--with-mpfr=</span><var>mpfrinstalldir</var></samp> option is shorthand for
878 <samp><span class="option">--with-mpfr-lib=</span><var>mpfrinstalldir</var><span class="option">/lib</span></samp> and
879 <samp><span class="option">--with-mpfr-include=</span><var>mpfrinstalldir</var><span class="option">/include</span></samp>, also the
880 <samp><span class="option">--with-mpc=</span><var>mpcinstalldir</var></samp> option is shorthand for
881 <samp><span class="option">--with-mpc-lib=</span><var>mpcinstalldir</var><span class="option">/lib</span></samp> and
882 <samp><span class="option">--with-mpc-include=</span><var>mpcinstalldir</var><span class="option">/include</span></samp>. If these
883 shorthand assumptions are not correct, you can use the explicit
884 include and lib options directly. You might also need to ensure the
885 shared libraries can be found by the dynamic linker when building and
886 using GCC, for example by setting the runtime shared library path
887 variable (<samp><span class="env">LD_LIBRARY_PATH</span></samp> on GNU/Linux and Solaris systems).
889 <p>These flags are applicable to the host platform only. When building
890 a cross compiler, they will not be used to configure target libraries.
892 <br><dt><code>--with-isl=</code><var>pathname</var><dt><code>--with-isl-include=</code><var>pathname</var><dt><code>--with-isl-lib=</code><var>pathname</var><dt><code>--with-cloog=</code><var>pathname</var><dt><code>--with-cloog-include=</code><var>pathname</var><dt><code>--with-cloog-lib=</code><var>pathname</var><dd>If you do not have ISL and the CLooG
893 libraries installed in a standard location and you want to build GCC,
894 you can explicitly specify the directory where they are installed
895 (‘<samp><span class="samp">--with-isl=</span><var>islinstalldir</var></samp>’,
896 ‘<samp><span class="samp">--with-cloog=</span><var>clooginstalldir</var></samp>’). The
897 <samp><span class="option">--with-isl=</span><var>islinstalldir</var></samp> option is shorthand for
898 <samp><span class="option">--with-isl-lib=</span><var>islinstalldir</var><span class="option">/lib</span></samp> and
899 <samp><span class="option">--with-isl-include=</span><var>islinstalldir</var><span class="option">/include</span></samp>. Likewise the
900 <samp><span class="option">--with-cloog=</span><var>clooginstalldir</var></samp> option is shorthand for
901 <samp><span class="option">--with-cloog-lib=</span><var>clooginstalldir</var><span class="option">/lib</span></samp> and
902 <samp><span class="option">--with-cloog-include=</span><var>clooginstalldir</var><span class="option">/include</span></samp>. If these
903 shorthand assumptions are not correct, you can use the explicit
904 include and lib options directly.
906 <p>These flags are applicable to the host platform only. When building
907 a cross compiler, they will not be used to configure target libraries.
909 <br><dt><code>--with-host-libstdcxx=</code><var>linker-args</var><dd>If you are linking with a static copy of PPL, you can use this option
910 to specify how the linker should find the standard C++ library used
911 internally by PPL. Typical values of <var>linker-args</var> might be
912 ‘<samp><span class="samp">-lstdc++</span></samp>’ or ‘<samp><span class="samp">-Wl,-Bstatic,-lstdc++,-Bdynamic -lm</span></samp>’. If you are
913 linking with a shared copy of PPL, you probably do not need this
914 option; shared library dependencies will cause the linker to search
915 for the standard C++ library automatically.
917 <br><dt><code>--with-stage1-ldflags=</code><var>flags</var><dd>This option may be used to set linker flags to be used when linking
918 stage 1 of GCC. These are also used when linking GCC if configured with
919 <samp><span class="option">--disable-bootstrap</span></samp>. By default no special flags are used.
921 <br><dt><code>--with-stage1-libs=</code><var>libs</var><dd>This option may be used to set libraries to be used when linking stage 1
922 of GCC. These are also used when linking GCC if configured with
923 <samp><span class="option">--disable-bootstrap</span></samp>. The default is the argument to
924 <samp><span class="option">--with-host-libstdcxx</span></samp>, if specified.
926 <br><dt><code>--with-boot-ldflags=</code><var>flags</var><dd>This option may be used to set linker flags to be used when linking
927 stage 2 and later when bootstrapping GCC. If neither –with-boot-libs
928 nor –with-host-libstdcxx is set to a value, then the default is
929 ‘<samp><span class="samp">-static-libstdc++ -static-libgcc</span></samp>’.
931 <br><dt><code>--with-boot-libs=</code><var>libs</var><dd>This option may be used to set libraries to be used when linking stage 2
932 and later when bootstrapping GCC. The default is the argument to
933 <samp><span class="option">--with-host-libstdcxx</span></samp>, if specified.
935 <br><dt><code>--with-debug-prefix-map=</code><var>map</var><dd>Convert source directory names using <samp><span class="option">-fdebug-prefix-map</span></samp> when
936 building runtime libraries. ‘<samp><var>map</var></samp>’ is a space-separated
937 list of maps of the form ‘<samp><var>old</var><span class="samp">=</span><var>new</var></samp>’.
939 <br><dt><code>--enable-linker-build-id</code><dd>Tells GCC to pass <samp><span class="option">--build-id</span></samp> option to the linker for all final
940 links (links performed without the <samp><span class="option">-r</span></samp> or <samp><span class="option">--relocatable</span></samp>
941 option), if the linker supports it. If you specify
942 <samp><span class="option">--enable-linker-build-id</span></samp>, but your linker does not
943 support <samp><span class="option">--build-id</span></samp> option, a warning is issued and the
944 <samp><span class="option">--enable-linker-build-id</span></samp> option is ignored. The default is off.
946 <br><dt><code>--with-linker-hash-style=</code><var>choice</var><dd>Tells GCC to pass <samp><span class="option">--hash-style=</span><var>choice</var></samp> option to the
947 linker for all final links. <var>choice</var> can be one of
948 ‘<samp><span class="samp">sysv</span></samp>’, ‘<samp><span class="samp">gnu</span></samp>’, and ‘<samp><span class="samp">both</span></samp>’ where ‘<samp><span class="samp">sysv</span></samp>’ is the default.
950 <br><dt><code>--enable-gnu-unique-object</code><dt><code>--disable-gnu-unique-object</code><dd>Tells GCC to use the gnu_unique_object relocation for C++ template
951 static data members and inline function local statics. Enabled by
952 default for a native toolchain with an assembler that accepts it and
953 GLIBC 2.11 or above, otherwise disabled.
955 <br><dt><code>--enable-lto</code><dt><code>--disable-lto</code><dd>Enable support for link-time optimization (LTO). This is enabled by
956 default, and may be disabled using <samp><span class="option">--disable-lto</span></samp>.
958 <br><dt><code>--with-plugin-ld=</code><var>pathname</var><dd>Enable an alternate linker to be used at link-time optimization (LTO)
959 link time when <samp><span class="option">-fuse-linker-plugin</span></samp> is enabled.
960 This linker should have plugin support such as gold starting with
961 version 2.20 or GNU ld starting with version 2.21.
962 See <samp><span class="option">-fuse-linker-plugin</span></samp> for details.
964 <br><dt><code>--enable-canonical-system-headers</code><dt><code>--disable-canonical-system-headers</code><dd>Enable system header path canonicalization for <samp><span class="file">libcpp</span></samp>. This can
965 produce shorter header file paths in diagnostics and dependency output
966 files, but these changed header paths may conflict with some compilation
967 environments. Enabled by default, and may be disabled using
968 <samp><span class="option">--disable-canonical-system-headers</span></samp>.
971 <h4 class="subheading"><a name="TOC3"></a>Cross-Compiler-Specific Options</h4>
973 <p>The following options only apply to building cross compilers.
976 <dt><code>--with-sysroot</code><dt><code>--with-sysroot=</code><var>dir</var><dd>Tells GCC to consider <var>dir</var> as the root of a tree that contains
977 (a subset of) the root filesystem of the target operating system.
978 Target system headers, libraries and run-time object files will be
979 searched for in there. More specifically, this acts as if
980 <samp><span class="option">--sysroot=</span><var>dir</var></samp> was added to the default options of the built
981 compiler. The specified directory is not copied into the
982 install tree, unlike the options <samp><span class="option">--with-headers</span></samp> and
983 <samp><span class="option">--with-libs</span></samp> that this option obsoletes. The default value,
984 in case <samp><span class="option">--with-sysroot</span></samp> is not given an argument, is
985 <samp><span class="option">${gcc_tooldir}/sys-root</span></samp>. If the specified directory is a
986 subdirectory of <samp><span class="option">${exec_prefix}</span></samp>, then it will be found relative to
987 the GCC binaries if the installation tree is moved.
989 <p>This option affects the system root for the compiler used to build
990 target libraries (which runs on the build system) and the compiler newly
991 installed with <code>make install</code>; it does not affect the compiler which is
992 used to build GCC itself.
994 <p>If you specify the <samp><span class="option">--with-native-system-header-dir=</span><var>dirname</var></samp>
995 option then the compiler will search that directory within <var>dirname</var> for
996 native system headers rather than the default <samp><span class="file">/usr/include</span></samp>.
998 <br><dt><code>--with-build-sysroot</code><dt><code>--with-build-sysroot=</code><var>dir</var><dd>Tells GCC to consider <var>dir</var> as the system root (see
999 <samp><span class="option">--with-sysroot</span></samp>) while building target libraries, instead of
1000 the directory specified with <samp><span class="option">--with-sysroot</span></samp>. This option is
1001 only useful when you are already using <samp><span class="option">--with-sysroot</span></samp>. You
1002 can use <samp><span class="option">--with-build-sysroot</span></samp> when you are configuring with
1003 <samp><span class="option">--prefix</span></samp> set to a directory that is different from the one in
1004 which you are installing GCC and your target libraries.
1006 <p>This option affects the system root for the compiler used to build
1007 target libraries (which runs on the build system); it does not affect
1008 the compiler which is used to build GCC itself.
1010 <p>If you specify the <samp><span class="option">--with-native-system-header-dir=</span><var>dirname</var></samp>
1011 option then the compiler will search that directory within <var>dirname</var> for
1012 native system headers rather than the default <samp><span class="file">/usr/include</span></samp>.
1014 <br><dt><code>--with-headers</code><dt><code>--with-headers=</code><var>dir</var><dd>Deprecated in favor of <samp><span class="option">--with-sysroot</span></samp>.
1015 Specifies that target headers are available when building a cross compiler.
1016 The <var>dir</var> argument specifies a directory which has the target include
1017 files. These include files will be copied into the <samp><span class="file">gcc</span></samp> install
1018 directory. <em>This option with the </em><var>dir</var><em> argument is required</em> when
1019 building a cross compiler, if <samp><var>prefix</var><span class="file">/</span><var>target</var><span class="file">/sys-include</span></samp>
1020 doesn't pre-exist. If <samp><var>prefix</var><span class="file">/</span><var>target</var><span class="file">/sys-include</span></samp> does
1021 pre-exist, the <var>dir</var> argument may be omitted. <samp><span class="command">fixincludes</span></samp>
1022 will be run on these files to make them compatible with GCC.
1024 <br><dt><code>--without-headers</code><dd>Tells GCC not use any target headers from a libc when building a cross
1025 compiler. When crossing to GNU/Linux, you need the headers so GCC
1026 can build the exception handling for libgcc.
1028 <br><dt><code>--with-libs</code><dt><code>--with-libs="</code><var>dir1</var> <var>dir2</var><code> ... </code><var>dirN</var><code>"</code><dd>Deprecated in favor of <samp><span class="option">--with-sysroot</span></samp>.
1029 Specifies a list of directories which contain the target runtime
1030 libraries. These libraries will be copied into the <samp><span class="file">gcc</span></samp> install
1031 directory. If the directory list is omitted, this option has no
1034 <br><dt><code>--with-newlib</code><dd>Specifies that ‘<samp><span class="samp">newlib</span></samp>’ is
1035 being used as the target C library. This causes <code>__eprintf</code> to be
1036 omitted from <samp><span class="file">libgcc.a</span></samp> on the assumption that it will be provided by
1037 ‘<samp><span class="samp">newlib</span></samp>’.
1039 <br><dt><code>--with-avrlibc</code><dd>Specifies that ‘<samp><span class="samp">AVR-Libc</span></samp>’ is
1040 being used as the target C library. This causes float support
1041 functions like <code>__addsf3</code> to be omitted from <samp><span class="file">libgcc.a</span></samp> on
1042 the assumption that it will be provided by <samp><span class="file">libm.a</span></samp>. For more
1043 technical details, cf. <a href="http://gcc.gnu.org/PR54461">PR54461</a>.
1044 This option is only supported for the AVR target. It is not supported for
1045 RTEMS configurations, which currently use newlib. The option is
1046 supported since version 4.7.2 and is the default in 4.8.0 and newer.
1048 <br><dt><code>--with-build-time-tools=</code><var>dir</var><dd>Specifies where to find the set of target tools (assembler, linker, etc.)
1049 that will be used while building GCC itself. This option can be useful
1050 if the directory layouts are different between the system you are building
1051 GCC on, and the system where you will deploy it.
1053 <p>For example, on an ‘<samp><span class="samp">ia64-hp-hpux</span></samp>’ system, you may have the GNU
1054 assembler and linker in <samp><span class="file">/usr/bin</span></samp>, and the native tools in a
1055 different path, and build a toolchain that expects to find the
1056 native tools in <samp><span class="file">/usr/bin</span></samp>.
1058 <p>When you use this option, you should ensure that <var>dir</var> includes
1059 <samp><span class="command">ar</span></samp>, <samp><span class="command">as</span></samp>, <samp><span class="command">ld</span></samp>, <samp><span class="command">nm</span></samp>,
1060 <samp><span class="command">ranlib</span></samp> and <samp><span class="command">strip</span></samp> if necessary, and possibly
1061 <samp><span class="command">objdump</span></samp>. Otherwise, GCC may use an inconsistent set of
1065 <h4 class="subheading"><a name="TOC4"></a>Java-Specific Options</h4>
1067 <p>The following option applies to the build of the Java front end.
1070 <dt><code>--disable-libgcj</code><dd>Specify that the run-time libraries
1071 used by GCJ should not be built. This is useful in case you intend
1072 to use GCJ with some other run-time, or you're going to install it
1073 separately, or it just happens not to build on your particular
1074 machine. In general, if the Java front end is enabled, the GCJ
1075 libraries will be enabled too, unless they're known to not work on
1076 the target platform. If GCJ is enabled but ‘<samp><span class="samp">libgcj</span></samp>’ isn't built, you
1077 may need to port it; in this case, before modifying the top-level
1078 <samp><span class="file">configure.in</span></samp> so that ‘<samp><span class="samp">libgcj</span></samp>’ is enabled by default on this platform,
1079 you may use <samp><span class="option">--enable-libgcj</span></samp> to override the default.
1083 <p>The following options apply to building ‘<samp><span class="samp">libgcj</span></samp>’.
1085 <h5 class="subsubheading"><a name="TOC5"></a>General Options</h5>
1088 <dt><code>--enable-java-maintainer-mode</code><dd>By default the ‘<samp><span class="samp">libjava</span></samp>’ build will not attempt to compile the
1089 <samp><span class="file">.java</span></samp> source files to <samp><span class="file">.class</span></samp>. Instead, it will use the
1090 <samp><span class="file">.class</span></samp> files from the source tree. If you use this option you
1091 must have executables named <samp><span class="command">ecj1</span></samp> and <samp><span class="command">gjavah</span></samp> in your path
1092 for use by the build. You must use this option if you intend to
1093 modify any <samp><span class="file">.java</span></samp> files in <samp><span class="file">libjava</span></samp>.
1095 <br><dt><code>--with-java-home=</code><var>dirname</var><dd>This ‘<samp><span class="samp">libjava</span></samp>’ option overrides the default value of the
1096 ‘<samp><span class="samp">java.home</span></samp>’ system property. It is also used to set
1097 ‘<samp><span class="samp">sun.boot.class.path</span></samp>’ to <samp><var>dirname</var><span class="file">/lib/rt.jar</span></samp>. By
1098 default ‘<samp><span class="samp">java.home</span></samp>’ is set to <samp><var>prefix</var></samp> and
1099 ‘<samp><span class="samp">sun.boot.class.path</span></samp>’ to
1100 <samp><var>datadir</var><span class="file">/java/libgcj-</span><var>version</var><span class="file">.jar</span></samp>.
1102 <br><dt><code>--with-ecj-jar=</code><var>filename</var><dd>This option can be used to specify the location of an external jar
1103 file containing the Eclipse Java compiler. A specially modified
1104 version of this compiler is used by <samp><span class="command">gcj</span></samp> to parse
1105 <samp><span class="file">.java</span></samp> source files. If this option is given, the
1106 ‘<samp><span class="samp">libjava</span></samp>’ build will create and install an <samp><span class="file">ecj1</span></samp> executable
1107 which uses this jar file at runtime.
1109 <p>If this option is not given, but an <samp><span class="file">ecj.jar</span></samp> file is found in
1110 the topmost source tree at configure time, then the ‘<samp><span class="samp">libgcj</span></samp>’
1111 build will create and install <samp><span class="file">ecj1</span></samp>, and will also install the
1112 discovered <samp><span class="file">ecj.jar</span></samp> into a suitable place in the install tree.
1114 <p>If <samp><span class="file">ecj1</span></samp> is not installed, then the user will have to supply one
1115 on his path in order for <samp><span class="command">gcj</span></samp> to properly parse <samp><span class="file">.java</span></samp>
1116 source files. A suitable jar is available from
1117 <a href="ftp://sourceware.org/pub/java/">ftp://sourceware.org/pub/java/</a>.
1119 <br><dt><code>--disable-getenv-properties</code><dd>Don't set system properties from <samp><span class="env">GCJ_PROPERTIES</span></samp>.
1121 <br><dt><code>--enable-hash-synchronization</code><dd>Use a global hash table for monitor locks. Ordinarily,
1122 ‘<samp><span class="samp">libgcj</span></samp>’'s ‘<samp><span class="samp">configure</span></samp>’ script automatically makes
1123 the correct choice for this option for your platform. Only use
1124 this if you know you need the library to be configured differently.
1126 <br><dt><code>--enable-interpreter</code><dd>Enable the Java interpreter. The interpreter is automatically
1127 enabled by default on all platforms that support it. This option
1128 is really only useful if you want to disable the interpreter
1129 (using <samp><span class="option">--disable-interpreter</span></samp>).
1131 <br><dt><code>--disable-java-net</code><dd>Disable java.net. This disables the native part of java.net only,
1132 using non-functional stubs for native method implementations.
1134 <br><dt><code>--disable-jvmpi</code><dd>Disable JVMPI support.
1136 <br><dt><code>--disable-libgcj-bc</code><dd>Disable BC ABI compilation of certain parts of libgcj. By default,
1137 some portions of libgcj are compiled with <samp><span class="option">-findirect-dispatch</span></samp>
1138 and <samp><span class="option">-fno-indirect-classes</span></samp>, allowing them to be overridden at
1141 <p>If <samp><span class="option">--disable-libgcj-bc</span></samp> is specified, libgcj is built without
1142 these options. This allows the compile-time linker to resolve
1143 dependencies when statically linking to libgcj. However it makes it
1144 impossible to override the affected portions of libgcj at run-time.
1146 <br><dt><code>--enable-reduced-reflection</code><dd>Build most of libgcj with <samp><span class="option">-freduced-reflection</span></samp>. This reduces
1147 the size of libgcj at the expense of not being able to do accurate
1148 reflection on the classes it contains. This option is safe if you
1149 know that code using libgcj will never use reflection on the standard
1150 runtime classes in libgcj (including using serialization, RMI or CORBA).
1152 <br><dt><code>--with-ecos</code><dd>Enable runtime eCos target support.
1154 <br><dt><code>--without-libffi</code><dd>Don't use ‘<samp><span class="samp">libffi</span></samp>’. This will disable the interpreter and JNI
1155 support as well, as these require ‘<samp><span class="samp">libffi</span></samp>’ to work.
1157 <br><dt><code>--enable-libgcj-debug</code><dd>Enable runtime debugging code.
1159 <br><dt><code>--enable-libgcj-multifile</code><dd>If specified, causes all <samp><span class="file">.java</span></samp> source files to be
1160 compiled into <samp><span class="file">.class</span></samp> files in one invocation of
1161 ‘<samp><span class="samp">gcj</span></samp>’. This can speed up build time, but is more
1162 resource-intensive. If this option is unspecified or
1163 disabled, ‘<samp><span class="samp">gcj</span></samp>’ is invoked once for each <samp><span class="file">.java</span></samp>
1164 file to compile into a <samp><span class="file">.class</span></samp> file.
1166 <br><dt><code>--with-libiconv-prefix=DIR</code><dd>Search for libiconv in <samp><span class="file">DIR/include</span></samp> and <samp><span class="file">DIR/lib</span></samp>.
1168 <br><dt><code>--enable-sjlj-exceptions</code><dd>Force use of the <code>setjmp</code>/<code>longjmp</code>-based scheme for exceptions.
1169 ‘<samp><span class="samp">configure</span></samp>’ ordinarily picks the correct value based on the platform.
1170 Only use this option if you are sure you need a different setting.
1172 <br><dt><code>--with-system-zlib</code><dd>Use installed ‘<samp><span class="samp">zlib</span></samp>’ rather than that included with GCC.
1174 <br><dt><code>--with-win32-nlsapi=ansi, unicows or unicode</code><dd>Indicates how MinGW ‘<samp><span class="samp">libgcj</span></samp>’ translates between UNICODE
1175 characters and the Win32 API.
1177 <br><dt><code>--enable-java-home</code><dd>If enabled, this creates a JPackage compatible SDK environment during install.
1178 Note that if –enable-java-home is used, –with-arch-directory=ARCH must also
1181 <br><dt><code>--with-arch-directory=ARCH</code><dd>Specifies the name to use for the <samp><span class="file">jre/lib/ARCH</span></samp> directory in the SDK
1182 environment created when –enable-java-home is passed. Typical names for this
1183 directory include i386, amd64, ia64, etc.
1185 <br><dt><code>--with-os-directory=DIR</code><dd>Specifies the OS directory for the SDK include directory. This is set to auto
1186 detect, and is typically 'linux'.
1188 <br><dt><code>--with-origin-name=NAME</code><dd>Specifies the JPackage origin name. This defaults to the 'gcj' in
1191 <br><dt><code>--with-arch-suffix=SUFFIX</code><dd>Specifies the suffix for the sdk directory. Defaults to the empty string.
1192 Examples include '.x86_64' in 'java-1.5.0-gcj-1.5.0.0.x86_64'.
1194 <br><dt><code>--with-jvm-root-dir=DIR</code><dd>Specifies where to install the SDK. Default is $(prefix)/lib/jvm.
1196 <br><dt><code>--with-jvm-jar-dir=DIR</code><dd>Specifies where to install jars. Default is $(prefix)/lib/jvm-exports.
1198 <br><dt><code>--with-python-dir=DIR</code><dd>Specifies where to install the Python modules used for aot-compile. DIR should
1199 not include the prefix used in installation. For example, if the Python modules
1200 are to be installed in /usr/lib/python2.5/site-packages, then
1201 –with-python-dir=/lib/python2.5/site-packages should be passed. If this is
1202 not specified, then the Python modules are installed in $(prefix)/share/python.
1204 <br><dt><code>--enable-aot-compile-rpm</code><dd>Adds aot-compile-rpm to the list of installed scripts.
1206 <br><dt><code>--enable-browser-plugin</code><dd>Build the gcjwebplugin web browser plugin.
1208 <br><dt><code>--enable-static-libjava</code><dd>Build static libraries in libjava. The default is to only build shared
1212 <dt><code>ansi</code><dd>Use the single-byte <code>char</code> and the Win32 A functions natively,
1213 translating to and from UNICODE when using these functions. If
1214 unspecified, this is the default.
1216 <br><dt><code>unicows</code><dd>Use the <code>WCHAR</code> and Win32 W functions natively. Adds
1217 <code>-lunicows</code> to <samp><span class="file">libgcj.spec</span></samp> to link with ‘<samp><span class="samp">libunicows</span></samp>’.
1218 <samp><span class="file">unicows.dll</span></samp> needs to be deployed on Microsoft Windows 9X machines
1219 running built executables. <samp><span class="file">libunicows.a</span></samp>, an open-source
1220 import library around Microsoft's <code>unicows.dll</code>, is obtained from
1221 <a href="http://libunicows.sourceforge.net/">http://libunicows.sourceforge.net/</a>, which also gives details
1222 on getting <samp><span class="file">unicows.dll</span></samp> from Microsoft.
1224 <br><dt><code>unicode</code><dd>Use the <code>WCHAR</code> and Win32 W functions natively. Does <em>not</em>
1225 add <code>-lunicows</code> to <samp><span class="file">libgcj.spec</span></samp>. The built executables will
1226 only run on Microsoft Windows NT and above.
1230 <h5 class="subsubheading"><a name="TOC6"></a>AWT-Specific Options</h5>
1233 <dt><code>--with-x</code><dd>Use the X Window System.
1235 <br><dt><code>--enable-java-awt=PEER(S)</code><dd>Specifies the AWT peer library or libraries to build alongside
1236 ‘<samp><span class="samp">libgcj</span></samp>’. If this option is unspecified or disabled, AWT
1237 will be non-functional. Current valid values are <samp><span class="option">gtk</span></samp> and
1238 <samp><span class="option">xlib</span></samp>. Multiple libraries should be separated by a
1239 comma (i.e. <samp><span class="option">--enable-java-awt=gtk,xlib</span></samp>).
1241 <br><dt><code>--enable-gtk-cairo</code><dd>Build the cairo Graphics2D implementation on GTK.
1243 <br><dt><code>--enable-java-gc=TYPE</code><dd>Choose garbage collector. Defaults to <samp><span class="option">boehm</span></samp> if unspecified.
1245 <br><dt><code>--disable-gtktest</code><dd>Do not try to compile and run a test GTK+ program.
1247 <br><dt><code>--disable-glibtest</code><dd>Do not try to compile and run a test GLIB program.
1249 <br><dt><code>--with-libart-prefix=PFX</code><dd>Prefix where libart is installed (optional).
1251 <br><dt><code>--with-libart-exec-prefix=PFX</code><dd>Exec prefix where libart is installed (optional).
1253 <br><dt><code>--disable-libarttest</code><dd>Do not try to compile and run a test libart program.
1257 <h5 class="subsubheading"><a name="TOC7"></a>Overriding <samp><span class="command">configure</span></samp> test results</h5>
1259 <p>Sometimes, it might be necessary to override the result of some
1260 <samp><span class="command">configure</span></samp> test, for example in order to ease porting to a new
1261 system or work around a bug in a test. The toplevel <samp><span class="command">configure</span></samp>
1262 script provides three variables for this:
1265 <dt><code>build_configargs</code><dd><a name="index-g_t_0040code_007bbuild_005fconfigargs_007d-3"></a>The contents of this variable is passed to all build <samp><span class="command">configure</span></samp>
1268 <br><dt><code>host_configargs</code><dd><a name="index-g_t_0040code_007bhost_005fconfigargs_007d-4"></a>The contents of this variable is passed to all host <samp><span class="command">configure</span></samp>
1271 <br><dt><code>target_configargs</code><dd><a name="index-g_t_0040code_007btarget_005fconfigargs_007d-5"></a>The contents of this variable is passed to all target <samp><span class="command">configure</span></samp>
1276 <p>In order to avoid shell and <samp><span class="command">make</span></samp> quoting issues for complex
1277 overrides, you can pass a setting for <samp><span class="env">CONFIG_SITE</span></samp> and set
1278 variables in the site file.
1281 <p><a href="./index.html">Return to the GCC Installation page</a>
1283 <!-- ***Building**************************************************************** -->
1284 <!-- ***Testing***************************************************************** -->
1285 <!-- ***Final install*********************************************************** -->
1286 <!-- ***Binaries**************************************************************** -->
1287 <!-- ***Specific**************************************************************** -->
1288 <!-- ***Old documentation****************************************************** -->
1289 <!-- ***GFDL******************************************************************** -->
1290 <!-- *************************************************************************** -->
1291 <!-- Part 6 The End of the Document -->
projects / platform / upstream / gcc48.git / blob