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44 <h1 class="settitle">Installing GCC: Configuration</h1>
45 <a name="index-Configuration-1"></a><a name="index-Installing-GCC_003a-Configuration-2"></a>
46 Like most GNU software, GCC must be configured before it can be built.
47 This document describes the recommended configuration procedure
48 for both native and cross targets.
50 <p>We use <var>srcdir</var> to refer to the toplevel source directory for
51 GCC; we use <var>objdir</var> to refer to the toplevel build/object directory.
53 <p>If you obtained the sources via SVN, <var>srcdir</var> must refer to the top
54 <samp><span class="file">gcc</span></samp> directory, the one where the <samp><span class="file">MAINTAINERS</span></samp> file can be
55 found, and not its <samp><span class="file">gcc</span></samp> subdirectory, otherwise the build will fail.
57 <p>If either <var>srcdir</var> or <var>objdir</var> is located on an automounted NFS
58 file system, the shell's built-in <samp><span class="command">pwd</span></samp> command will return
59 temporary pathnames. Using these can lead to various sorts of build
60 problems. To avoid this issue, set the <samp><span class="env">PWDCMD</span></samp> environment
61 variable to an automounter-aware <samp><span class="command">pwd</span></samp> command, e.g.,
62 <samp><span class="command">pawd</span></samp> or ‘<samp><span class="samp">amq -w</span></samp>’, during the configuration and build
65 <p>First, we <strong>highly</strong> recommend that GCC be built into a
66 separate directory from the sources which does <strong>not</strong> reside
67 within the source tree. This is how we generally build GCC; building
68 where <var>srcdir</var> == <var>objdir</var> should still work, but doesn't
69 get extensive testing; building where <var>objdir</var> is a subdirectory
70 of <var>srcdir</var> is unsupported.
72 <p>If you have previously built GCC in the same directory for a
73 different target machine, do ‘<samp><span class="samp">make distclean</span></samp>’ to delete all files
74 that might be invalid. One of the files this deletes is <samp><span class="file">Makefile</span></samp>;
75 if ‘<samp><span class="samp">make distclean</span></samp>’ complains that <samp><span class="file">Makefile</span></samp> does not exist
76 or issues a message like “don't know how to make distclean” it probably
77 means that the directory is already suitably clean. However, with the
78 recommended method of building in a separate <var>objdir</var>, you should
79 simply use a different <var>objdir</var> for each target.
81 <p>Second, when configuring a native system, either <samp><span class="command">cc</span></samp> or
82 <samp><span class="command">gcc</span></samp> must be in your path or you must set <samp><span class="env">CC</span></samp> in
83 your environment before running configure. Otherwise the configuration
88 <pre class="smallexample"> % mkdir <var>objdir</var>
89 % cd <var>objdir</var>
90 % <var>srcdir</var>/configure [<var>options</var>] [<var>target</var>]
92 <h3 class="heading"><a name="TOC0"></a>Distributor options</h3>
94 <p>If you will be distributing binary versions of GCC, with modifications
95 to the source code, you should use the options described in this
96 section to make clear that your version contains modifications.
99 <dt><code>--with-pkgversion=</code><var>version</var><dd>Specify a string that identifies your package. You may wish
100 to include a build number or build date. This version string will be
101 included in the output of <samp><span class="command">gcc --version</span></samp>. This suffix does
102 not replace the default version string, only the ‘<samp><span class="samp">GCC</span></samp>’ part.
104 <p>The default value is ‘<samp><span class="samp">GCC</span></samp>’.
106 <br><dt><code>--with-bugurl=</code><var>url</var><dd>Specify the URL that users should visit if they wish to report a bug.
107 You are of course welcome to forward bugs reported to you to the FSF,
108 if you determine that they are not bugs in your modifications.
110 <p>The default value refers to the FSF's GCC bug tracker.
114 <h3 class="heading"><a name="TOC1"></a>Target specification</h3>
117 <li>GCC has code to correctly determine the correct value for <var>target</var>
118 for nearly all native systems. Therefore, we highly recommend you do
119 not provide a configure target when configuring a native compiler.
121 <li><var>target</var> must be specified as <samp><span class="option">--target=</span><var>target</var></samp>
122 when configuring a cross compiler; examples of valid targets would be
123 m68k-elf, sh-elf, etc.
125 <li>Specifying just <var>target</var> instead of <samp><span class="option">--target=</span><var>target</var></samp>
126 implies that the host defaults to <var>target</var>.
129 <h3 class="heading"><a name="TOC2"></a>Options specification</h3>
131 <p>Use <var>options</var> to override several configure time options for
132 GCC. A list of supported <var>options</var> follows; ‘<samp><span class="samp">configure
133 --help</span></samp>’ may list other options, but those not listed below may not
134 work and should not normally be used.
136 <p>Note that each <samp><span class="option">--enable</span></samp> option has a corresponding
137 <samp><span class="option">--disable</span></samp> option and that each <samp><span class="option">--with</span></samp> option has a
138 corresponding <samp><span class="option">--without</span></samp> option.
141 <dt><code>--prefix=</code><var>dirname</var><dd>Specify the toplevel installation
142 directory. This is the recommended way to install the tools into a directory
143 other than the default. The toplevel installation directory defaults to
144 <samp><span class="file">/usr/local</span></samp>.
146 <p>We <strong>highly</strong> recommend against <var>dirname</var> being the same or a
147 subdirectory of <var>objdir</var> or vice versa. If specifying a directory
148 beneath a user's home directory tree, some shells will not expand
149 <var>dirname</var> correctly if it contains the ‘<samp><span class="samp">~</span></samp>’ metacharacter; use
150 <samp><span class="env">$HOME</span></samp> instead.
152 <p>The following standard <samp><span class="command">autoconf</span></samp> options are supported. Normally you
153 should not need to use these options.
155 <dt><code>--exec-prefix=</code><var>dirname</var><dd>Specify the toplevel installation directory for architecture-dependent
156 files. The default is <samp><var>prefix</var></samp>.
158 <br><dt><code>--bindir=</code><var>dirname</var><dd>Specify the installation directory for the executables called by users
159 (such as <samp><span class="command">gcc</span></samp> and <samp><span class="command">g++</span></samp>). The default is
160 <samp><var>exec-prefix</var><span class="file">/bin</span></samp>.
162 <br><dt><code>--libdir=</code><var>dirname</var><dd>Specify the installation directory for object code libraries and
163 internal data files of GCC. The default is <samp><var>exec-prefix</var><span class="file">/lib</span></samp>.
165 <br><dt><code>--libexecdir=</code><var>dirname</var><dd>Specify the installation directory for internal executables of GCC.
166 The default is <samp><var>exec-prefix</var><span class="file">/libexec</span></samp>.
168 <br><dt><code>--with-slibdir=</code><var>dirname</var><dd>Specify the installation directory for the shared libgcc library. The
169 default is <samp><var>libdir</var></samp>.
171 <br><dt><code>--datarootdir=</code><var>dirname</var><dd>Specify the root of the directory tree for read-only architecture-independent
172 data files referenced by GCC. The default is <samp><var>prefix</var><span class="file">/share</span></samp>.
174 <br><dt><code>--infodir=</code><var>dirname</var><dd>Specify the installation directory for documentation in info format.
175 The default is <samp><var>datarootdir</var><span class="file">/info</span></samp>.
177 <br><dt><code>--datadir=</code><var>dirname</var><dd>Specify the installation directory for some architecture-independent
178 data files referenced by GCC. The default is <samp><var>datarootdir</var></samp>.
180 <br><dt><code>--docdir=</code><var>dirname</var><dd>Specify the installation directory for documentation files (other
181 than Info) for GCC. The default is <samp><var>datarootdir</var><span class="file">/doc</span></samp>.
183 <br><dt><code>--htmldir=</code><var>dirname</var><dd>Specify the installation directory for HTML documentation files.
184 The default is <samp><var>docdir</var></samp>.
186 <br><dt><code>--pdfdir=</code><var>dirname</var><dd>Specify the installation directory for PDF documentation files.
187 The default is <samp><var>docdir</var></samp>.
189 <br><dt><code>--mandir=</code><var>dirname</var><dd>Specify the installation directory for manual pages. The default is
190 <samp><var>datarootdir</var><span class="file">/man</span></samp>. (Note that the manual pages are only extracts
191 from the full GCC manuals, which are provided in Texinfo format. The manpages
192 are derived by an automatic conversion process from parts of the full
195 <br><dt><code>--with-gxx-include-dir=</code><var>dirname</var><dd>Specify
196 the installation directory for G++ header files. The default depends
197 on other configuration options, and differs between cross and native
200 <br><dt><code>--with-specs=</code><var>specs</var><dd>Specify additional command line driver SPECS.
201 This can be useful if you need to turn on a non-standard feature by
202 default without modifying the compiler's source code, for instance
203 <samp><span class="option">--with-specs=%{!fcommon:%{!fno-common:-fno-common}}</span></samp>.
204 See “Spec Files” in the main manual
208 <br><dt><code>--program-prefix=</code><var>prefix</var><dd>GCC supports some transformations of the names of its programs when
209 installing them. This option prepends <var>prefix</var> to the names of
210 programs to install in <var>bindir</var> (see above). For example, specifying
211 <samp><span class="option">--program-prefix=foo-</span></samp> would result in ‘<samp><span class="samp">gcc</span></samp>’
212 being installed as <samp><span class="file">/usr/local/bin/foo-gcc</span></samp>.
214 <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>
215 (see above). For example, specifying <samp><span class="option">--program-suffix=-3.1</span></samp>
216 would result in ‘<samp><span class="samp">gcc</span></samp>’ being installed as
217 <samp><span class="file">/usr/local/bin/gcc-3.1</span></samp>.
219 <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
220 of programs to install in <var>bindir</var> (see above). <var>pattern</var> has to
221 consist of one or more basic ‘<samp><span class="samp">sed</span></samp>’ editing commands, separated by
222 semicolons. For example, if you want the ‘<samp><span class="samp">gcc</span></samp>’ program name to be
223 transformed to the installed program <samp><span class="file">/usr/local/bin/myowngcc</span></samp> and
224 the ‘<samp><span class="samp">g++</span></samp>’ program name to be transformed to
225 <samp><span class="file">/usr/local/bin/gspecial++</span></samp> without changing other program names,
226 you could use the pattern
227 <samp><span class="option">--program-transform-name='s/^gcc$/myowngcc/; s/^g++$/gspecial++/'</span></samp>
228 to achieve this effect.
230 <p>All three options can be combined and used together, resulting in more
231 complex conversion patterns. As a basic rule, <var>prefix</var> (and
232 <var>suffix</var>) are prepended (appended) before further transformations
233 can happen with a special transformation script <var>pattern</var>.
235 <p>As currently implemented, this option only takes effect for native
236 builds; cross compiler binaries' names are not transformed even when a
237 transformation is explicitly asked for by one of these options.
239 <p>For native builds, some of the installed programs are also installed
240 with the target alias in front of their name, as in
241 ‘<samp><span class="samp">i686-pc-linux-gnu-gcc</span></samp>’. All of the above transformations happen
242 before the target alias is prepended to the name—so, specifying
243 <samp><span class="option">--program-prefix=foo-</span></samp> and <samp><span class="option">program-suffix=-3.1</span></samp>, the
244 resulting binary would be installed as
245 <samp><span class="file">/usr/local/bin/i686-pc-linux-gnu-foo-gcc-3.1</span></samp>.
247 <p>As a last shortcoming, none of the installed Ada programs are
248 transformed yet, which will be fixed in some time.
250 <br><dt><code>--with-local-prefix=</code><var>dirname</var><dd>Specify the
251 installation directory for local include files. The default is
252 <samp><span class="file">/usr/local</span></samp>. Specify this option if you want the compiler to
253 search directory <samp><var>dirname</var><span class="file">/include</span></samp> for locally installed
254 header files <em>instead</em> of <samp><span class="file">/usr/local/include</span></samp>.
256 <p>You should specify <samp><span class="option">--with-local-prefix</span></samp> <strong>only</strong> if your
257 site has a different convention (not <samp><span class="file">/usr/local</span></samp>) for where to put
260 <p>The default value for <samp><span class="option">--with-local-prefix</span></samp> is <samp><span class="file">/usr/local</span></samp>
261 regardless of the value of <samp><span class="option">--prefix</span></samp>. Specifying
262 <samp><span class="option">--prefix</span></samp> has no effect on which directory GCC searches for
263 local header files. This may seem counterintuitive, but actually it is
266 <p>The purpose of <samp><span class="option">--prefix</span></samp> is to specify where to <em>install
267 GCC</em>. The local header files in <samp><span class="file">/usr/local/include</span></samp>—if you put
268 any in that directory—are not part of GCC. They are part of other
269 programs—perhaps many others. (GCC installs its own header files in
270 another directory which is based on the <samp><span class="option">--prefix</span></samp> value.)
272 <p>Both the local-prefix include directory and the GCC-prefix include
273 directory are part of GCC's “system include” directories. Although these
274 two directories are not fixed, they need to be searched in the proper
275 order for the correct processing of the include_next directive. The
276 local-prefix include directory is searched before the GCC-prefix
277 include directory. Another characteristic of system include directories
278 is that pedantic warnings are turned off for headers in these directories.
280 <p>Some autoconf macros add <samp><span class="option">-I </span><var>directory</var></samp> options to the
281 compiler command line, to ensure that directories containing installed
282 packages' headers are searched. When <var>directory</var> is one of GCC's
283 system include directories, GCC will ignore the option so that system
284 directories continue to be processed in the correct order. This
285 may result in a search order different from what was specified but the
286 directory will still be searched.
288 <p>GCC automatically searches for ordinary libraries using
289 <samp><span class="env">GCC_EXEC_PREFIX</span></samp>. Thus, when the same installation prefix is
290 used for both GCC and packages, GCC will automatically search for
291 both headers and libraries. This provides a configuration that is
292 easy to use. GCC behaves in a manner similar to that when it is
293 installed as a system compiler in <samp><span class="file">/usr</span></samp>.
295 <p>Sites that need to install multiple versions of GCC may not want to
296 use the above simple configuration. It is possible to use the
297 <samp><span class="option">--program-prefix</span></samp>, <samp><span class="option">--program-suffix</span></samp> and
298 <samp><span class="option">--program-transform-name</span></samp> options to install multiple versions
299 into a single directory, but it may be simpler to use different prefixes
300 and the <samp><span class="option">--with-local-prefix</span></samp> option to specify the location of the
301 site-specific files for each version. It will then be necessary for
302 users to specify explicitly the location of local site libraries
303 (e.g., with <samp><span class="env">LIBRARY_PATH</span></samp>).
305 <p>The same value can be used for both <samp><span class="option">--with-local-prefix</span></samp> and
306 <samp><span class="option">--prefix</span></samp> provided it is not <samp><span class="file">/usr</span></samp>. This can be used
307 to avoid the default search of <samp><span class="file">/usr/local/include</span></samp>.
309 <p><strong>Do not</strong> specify <samp><span class="file">/usr</span></samp> as the <samp><span class="option">--with-local-prefix</span></samp>!
310 The directory you use for <samp><span class="option">--with-local-prefix</span></samp> <strong>must not</strong>
311 contain any of the system's standard header files. If it did contain
312 them, certain programs would be miscompiled (including GNU Emacs, on
313 certain targets), because this would override and nullify the header
314 file corrections made by the <samp><span class="command">fixincludes</span></samp> script.
316 <p>Indications are that people who use this option use it based on mistaken
317 ideas of what it is for. People use it as if it specified where to
318 install part of GCC. Perhaps they make this assumption because
319 installing GCC creates the directory.
321 <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
322 header files, rather than <samp><span class="file">/usr/include</span></samp>. This option is most useful
323 if you are creating a compiler that should be isolated from the system
324 as much as possible. It is most commonly used with the
325 <samp><span class="option">--with-sysroot</span></samp> option and will cause GCC to search
326 <var>dirname</var> inside the system root specified by that option.
328 <br><dt><code>--enable-shared[=</code><var>package</var><code>[,...]]</code><dd>Build shared versions of libraries, if shared libraries are supported on
329 the target platform. Unlike GCC 2.95.x and earlier, shared libraries
330 are enabled by default on all platforms that support shared libraries.
332 <p>If a list of packages is given as an argument, build shared libraries
333 only for the listed packages. For other packages, only static libraries
334 will be built. Package names currently recognized in the GCC tree are
335 ‘<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
336 ‘<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>’,
337 ‘<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>’.
338 Note ‘<samp><span class="samp">libiberty</span></samp>’ does not support shared libraries at all.
340 <p>Use <samp><span class="option">--disable-shared</span></samp> to build only static libraries. Note that
341 <samp><span class="option">--disable-shared</span></samp> does not accept a list of package names as
342 argument, only <samp><span class="option">--enable-shared</span></samp> does.
344 <br><dt><code><a name="with_002dgnu_002das"></a>--with-gnu-as</code><dd>Specify that the compiler should assume that the
345 assembler it finds is the GNU assembler. However, this does not modify
346 the rules to find an assembler and will result in confusion if the
347 assembler found is not actually the GNU assembler. (Confusion may also
348 result if the compiler finds the GNU assembler but has not been
349 configured with <samp><span class="option">--with-gnu-as</span></samp>.) If you have more than one
350 assembler installed on your system, you may want to use this option in
351 connection with <samp><span class="option">--with-as=</span><var>pathname</var></samp> or
352 <samp><span class="option">--with-build-time-tools=</span><var>pathname</var></samp>.
354 <p>The following systems are the only ones where it makes a difference
355 whether you use the GNU assembler. On any other system,
356 <samp><span class="option">--with-gnu-as</span></samp> has no effect.
359 <li>‘<samp><span class="samp">hppa1.0-</span><var>any</var><span class="samp">-</span><var>any</var></samp>’
360 <li>‘<samp><span class="samp">hppa1.1-</span><var>any</var><span class="samp">-</span><var>any</var></samp>’
361 <li>‘<samp><span class="samp">sparc-sun-solaris2.</span><var>any</var></samp>’
362 <li>‘<samp><span class="samp">sparc64-</span><var>any</var><span class="samp">-solaris2.</span><var>any</var></samp>’
365 <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
366 <var>pathname</var>, rather than the one found by the standard rules to find
367 an assembler, which are:
369 <li>Unless GCC is being built with a cross compiler, check the
370 <samp><var>libexec</var><span class="file">/gcc/</span><var>target</var><span class="file">/</span><var>version</var></samp> directory.
371 <var>libexec</var> defaults to <samp><var>exec-prefix</var><span class="file">/libexec</span></samp>;
372 <var>exec-prefix</var> defaults to <var>prefix</var>, which
373 defaults to <samp><span class="file">/usr/local</span></samp> unless overridden by the
374 <samp><span class="option">--prefix=</span><var>pathname</var></samp> switch described above. <var>target</var>
375 is the target system triple, such as ‘<samp><span class="samp">sparc-sun-solaris2.7</span></samp>’, and
376 <var>version</var> denotes the GCC version, such as 3.0.
378 <li>If the target system is the same that you are building on, check
379 operating system specific directories (e.g. <samp><span class="file">/usr/ccs/bin</span></samp> on
382 <li>Check in the <samp><span class="env">PATH</span></samp> for a tool whose name is prefixed by the
383 target system triple.
385 <li>Check in the <samp><span class="env">PATH</span></samp> for a tool whose name is not prefixed by the
386 target system triple, if the host and target system triple are
387 the same (in other words, we use a host tool if it can be used for
391 <p>You may want to use <samp><span class="option">--with-as</span></samp> if no assembler
392 is installed in the directories listed above, or if you have multiple
393 assemblers installed and want to choose one that is not found by the
396 <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>
399 <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>
402 <br><dt><code>--with-stabs</code><dd>Specify that stabs debugging
403 information should be used instead of whatever format the host normally
404 uses. Normally GCC uses the same debug format as the host system.
406 <p>On MIPS based systems and on Alphas, you must specify whether you want
407 GCC to create the normal ECOFF debugging format, or to use BSD-style
408 stabs passed through the ECOFF symbol table. The normal ECOFF debug
409 format cannot fully handle languages other than C. BSD stabs format can
410 handle other languages, but it only works with the GNU debugger GDB.
412 <p>Normally, GCC uses the ECOFF debugging format by default; if you
413 prefer BSD stabs, specify <samp><span class="option">--with-stabs</span></samp> when you configure GCC.
415 <p>No matter which default you choose when you configure GCC, the user
416 can use the <samp><span class="option">-gcoff</span></samp> and <samp><span class="option">-gstabs+</span></samp> options to specify explicitly
417 the debug format for a particular compilation.
419 <p><samp><span class="option">--with-stabs</span></samp> is meaningful on the ISC system on the 386, also, if
420 <samp><span class="option">--with-gas</span></samp> is used. It selects use of stabs debugging
421 information embedded in COFF output. This kind of debugging information
422 supports C++ well; ordinary COFF debugging information does not.
424 <p><samp><span class="option">--with-stabs</span></samp> is also meaningful on 386 systems running SVR4. It
425 selects use of stabs debugging information embedded in ELF output. The
426 C++ compiler currently (2.6.0) does not support the DWARF debugging
427 information normally used on 386 SVR4 platforms; stabs provide a
428 workable alternative. This requires gas and gdb, as the normal SVR4
429 tools can not generate or interpret stabs.
431 <br><dt><code>--with-tls=</code><var>dialect</var><dd>Specify the default TLS dialect, for systems were there is a choice.
432 For ARM targets, possible values for <var>dialect</var> are <code>gnu</code> or
433 <code>gnu2</code>, which select between the original GNU dialect and the GNU TLS
434 descriptor-based dialect.
436 <br><dt><code>--disable-multilib</code><dd>Specify that multiple target
437 libraries to support different target variants, calling
438 conventions, etc. should not be built. The default is to build a
439 predefined set of them.
441 <p>Some targets provide finer-grained control over which multilibs are built
442 (e.g., <samp><span class="option">--disable-softfloat</span></samp>):
444 <dt><code>arm-*-*</code><dd>fpu, 26bit, underscore, interwork, biendian, nofmult.
446 <br><dt><code>m68*-*-*</code><dd>softfloat, m68881, m68000, m68020.
448 <br><dt><code>mips*-*-*</code><dd>single-float, biendian, softfloat.
450 <br><dt><code>powerpc*-*-*, rs6000*-*-*</code><dd>aix64, pthread, softfloat, powercpu, powerpccpu, powerpcos, biendian,
455 <br><dt><code>--with-multilib-list=</code><var>list</var><dt><code>--without-multilib-list</code><dd>Specify what multilibs to build.
456 Currently only implemented for sh*-*-* and x86-64-*-linux*.
459 <dt><code>sh*-*-*</code><dd><var>list</var> is a comma separated list of CPU names. These must be of the
460 form <code>sh*</code> or <code>m*</code> (in which case they match the compiler option
461 for that processor). The list should not contain any endian options -
462 these are handled by <samp><span class="option">--with-endian</span></samp>.
464 <p>If <var>list</var> is empty, then there will be no multilibs for extra
465 processors. The multilib for the secondary endian remains enabled.
467 <p>As a special case, if an entry in the list starts with a <code>!</code>
468 (exclamation point), then it is added to the list of excluded multilibs.
469 Entries of this sort should be compatible with ‘<samp><span class="samp">MULTILIB_EXCLUDES</span></samp>’
470 (once the leading <code>!</code> has been stripped).
472 <p>If <samp><span class="option">--with-multilib-list</span></samp> is not given, then a default set of
473 multilibs is selected based on the value of <samp><span class="option">--target</span></samp>. This is
474 usually the complete set of libraries, but some targets imply a more
477 <p>Example 1: to configure a compiler for SH4A only, but supporting both
478 endians, with little endian being the default:
479 <pre class="smallexample"> --with-cpu=sh4a --with-endian=little,big --with-multilib-list=
481 <p>Example 2: to configure a compiler for both SH4A and SH4AL-DSP, but with
482 only little endian SH4AL:
483 <pre class="smallexample"> --with-cpu=sh4a --with-endian=little,big \
484 --with-multilib-list=sh4al,!mb/m4al
486 <br><dt><code>x86-64-*-linux*</code><dd><var>list</var> is a comma separated list of <code>m32</code>, <code>m64</code> and
487 <code>mx32</code> to enable 32-bit, 64-bit and x32 run-time libraries,
488 respectively. If <var>list</var> is empty, then there will be no multilibs
489 and only the default run-time library will be enabled.
491 <p>If <samp><span class="option">--with-multilib-list</span></samp> is not given, then only 32-bit and
492 64-bit run-time libraries will be enabled.
495 <br><dt><code>--with-endian=</code><var>endians</var><dd>Specify what endians to use.
496 Currently only implemented for sh*-*-*.
498 <p><var>endians</var> may be one of the following:
500 <dt><code>big</code><dd>Use big endian exclusively.
501 <br><dt><code>little</code><dd>Use little endian exclusively.
502 <br><dt><code>big,little</code><dd>Use big endian by default. Provide a multilib for little endian.
503 <br><dt><code>little,big</code><dd>Use little endian by default. Provide a multilib for big endian.
506 <br><dt><code>--enable-threads</code><dd>Specify that the target
507 supports threads. This affects the Objective-C compiler and runtime
508 library, and exception handling for other languages like C++ and Java.
509 On some systems, this is the default.
511 <p>In general, the best (and, in many cases, the only known) threading
512 model available will be configured for use. Beware that on some
513 systems, GCC has not been taught what threading models are generally
514 available for the system. In this case, <samp><span class="option">--enable-threads</span></samp> is an
515 alias for <samp><span class="option">--enable-threads=single</span></samp>.
517 <br><dt><code>--disable-threads</code><dd>Specify that threading support should be disabled for the system.
518 This is an alias for <samp><span class="option">--enable-threads=single</span></samp>.
520 <br><dt><code>--enable-threads=</code><var>lib</var><dd>Specify that
521 <var>lib</var> is the thread support library. This affects the Objective-C
522 compiler and runtime library, and exception handling for other languages
523 like C++ and Java. The possibilities for <var>lib</var> are:
526 <dt><code>aix</code><dd>AIX thread support.
527 <br><dt><code>dce</code><dd>DCE thread support.
528 <br><dt><code>lynx</code><dd>LynxOS thread support.
529 <br><dt><code>mipssde</code><dd>MIPS SDE thread support.
530 <br><dt><code>no</code><dd>This is an alias for ‘<samp><span class="samp">single</span></samp>’.
531 <br><dt><code>posix</code><dd>Generic POSIX/Unix98 thread support.
532 <br><dt><code>rtems</code><dd>RTEMS thread support.
533 <br><dt><code>single</code><dd>Disable thread support, should work for all platforms.
534 <br><dt><code>tpf</code><dd>TPF thread support.
535 <br><dt><code>vxworks</code><dd>VxWorks thread support.
536 <br><dt><code>win32</code><dd>Microsoft Win32 API thread support.
539 <br><dt><code>--enable-tls</code><dd>Specify that the target supports TLS (Thread Local Storage). Usually
540 configure can correctly determine if TLS is supported. In cases where
541 it guesses incorrectly, TLS can be explicitly enabled or disabled with
542 <samp><span class="option">--enable-tls</span></samp> or <samp><span class="option">--disable-tls</span></samp>. This can happen if
543 the assembler supports TLS but the C library does not, or if the
544 assumptions made by the configure test are incorrect.
546 <br><dt><code>--disable-tls</code><dd>Specify that the target does not support TLS.
547 This is an alias for <samp><span class="option">--enable-tls=no</span></samp>.
549 <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.
550 <var>cpu</var> will be used as the default value of the <samp><span class="option">-mcpu=</span></samp> switch.
551 This option is only supported on some targets, including ARM, i386, M68k,
552 PowerPC, and SPARC. The <samp><span class="option">--with-cpu-32</span></samp> and
553 <samp><span class="option">--with-cpu-64</span></samp> options specify separate default CPUs for
554 32-bit and 64-bit modes; these options are only supported for i386,
557 <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>,
558 <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>
559 options and for <samp><span class="option">-mhard-float</span></samp> or <samp><span class="option">-msoft-float</span></samp>. As with
560 <samp><span class="option">--with-cpu</span></samp>, which switches will be accepted and acceptable values
561 of the arguments depend on the target.
563 <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>.
564 This option is only supported on ARM targets.
566 <br><dt><code>--with-stack-offset=</code><var>num</var><dd>This option sets the default for the -mstack-offset=<var>num</var> option,
567 and will thus generally also control the setting of this option for
568 libraries. This option is only supported on Epiphany targets.
570 <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
571 ISA for floating-point arithmetics. You can select either ‘<samp><span class="samp">sse</span></samp>’ which
572 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.
573 This option is only supported on i386 and x86-64 targets.
575 <br><dt><code>--with-divide=</code><var>type</var><dd>Specify how the compiler should generate code for checking for
576 division by zero. This option is only supported on the MIPS target.
577 The possibilities for <var>type</var> are:
579 <dt><code>traps</code><dd>Division by zero checks use conditional traps (this is the default on
580 systems that support conditional traps).
581 <br><dt><code>breaks</code><dd>Division by zero checks use the break instruction.
584 <!-- If you make -with-llsc the default for additional targets, -->
585 <!-- update the -with-llsc description in the MIPS section below. -->
586 <br><dt><code>--with-llsc</code><dd>On MIPS targets, make <samp><span class="option">-mllsc</span></samp> the default when no
587 <samp><span class="option">-mno-llsc</span></samp> option is passed. This is the default for
588 Linux-based targets, as the kernel will emulate them if the ISA does
591 <br><dt><code>--without-llsc</code><dd>On MIPS targets, make <samp><span class="option">-mno-llsc</span></samp> the default when no
592 <samp><span class="option">-mllsc</span></samp> option is passed.
594 <br><dt><code>--with-synci</code><dd>On MIPS targets, make <samp><span class="option">-msynci</span></samp> the default when no
595 <samp><span class="option">-mno-synci</span></samp> option is passed.
597 <br><dt><code>--without-synci</code><dd>On MIPS targets, make <samp><span class="option">-mno-synci</span></samp> the default when no
598 <samp><span class="option">-msynci</span></samp> option is passed. This is the default.
600 <br><dt><code>--with-mips-plt</code><dd>On MIPS targets, make use of copy relocations and PLTs.
601 These features are extensions to the traditional
602 SVR4-based MIPS ABIs and require support from GNU binutils
603 and the runtime C library.
605 <br><dt><code>--enable-__cxa_atexit</code><dd>Define if you want to use __cxa_atexit, rather than atexit, to
606 register C++ destructors for local statics and global objects.
607 This is essential for fully standards-compliant handling of
608 destructors, but requires __cxa_atexit in libc. This option is currently
609 only available on systems with GNU libc. When enabled, this will cause
610 <samp><span class="option">-fuse-cxa-atexit</span></samp> to be passed by default.
612 <br><dt><code>--enable-gnu-indirect-function</code><dd>Define if you want to enable the <code>ifunc</code> attribute. This option is
613 currently only available on systems with GNU libc on certain targets.
615 <br><dt><code>--enable-target-optspace</code><dd>Specify that target
616 libraries should be optimized for code space instead of code speed.
617 This is the default for the m32r platform.
619 <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
620 in <samp><var>prefix</var><span class="file">/</span><var>dirname</var><span class="file">/cpp</span></samp>, in addition to <var>bindir</var>.
622 <br><dt><code>--enable-comdat</code><dd>Enable COMDAT group support. This is primarily used to override the
623 automatically detected value.
625 <br><dt><code>--enable-initfini-array</code><dd>Force the use of sections <code>.init_array</code> and <code>.fini_array</code>
626 (instead of <code>.init</code> and <code>.fini</code>) for constructors and
627 destructors. Option <samp><span class="option">--disable-initfini-array</span></samp> has the
628 opposite effect. If neither option is specified, the configure script
629 will try to guess whether the <code>.init_array</code> and
630 <code>.fini_array</code> sections are supported and, if they are, use them.
632 <br><dt><code>--enable-build-with-cxx</code><dd>Build GCC using a C++ compiler rather than a C compiler. This is an
633 experimental option which may become the default in a later release.
635 <br><dt><code>--enable-build-poststage1-with-cxx</code><dd>When bootstrapping, build stages 2 and 3 of GCC using a C++ compiler
636 rather than a C compiler. Stage 1 is still built with a C compiler.
637 This is enabled by default and may be disabled using
638 <samp><span class="option">--disable-build-poststage1-with-cxx</span></samp>.
640 <br><dt><code>--enable-maintainer-mode</code><dd>The build rules that regenerate the Autoconf and Automake output files as
641 well as the GCC master message catalog <samp><span class="file">gcc.pot</span></samp> are normally
642 disabled. This is because it can only be rebuilt if the complete source
643 tree is present. If you have changed the sources and want to rebuild the
644 catalog, configuring with <samp><span class="option">--enable-maintainer-mode</span></samp> will enable
645 this. Note that you need a recent version of the <code>gettext</code> tools
648 <br><dt><code>--disable-bootstrap</code><dd>For a native build, the default configuration is to perform
649 a 3-stage bootstrap of the compiler when ‘<samp><span class="samp">make</span></samp>’ is invoked,
650 testing that GCC can compile itself correctly. If you want to disable
651 this process, you can configure with <samp><span class="option">--disable-bootstrap</span></samp>.
653 <br><dt><code>--enable-bootstrap</code><dd>In special cases, you may want to perform a 3-stage build
654 even if the target and host triplets are different.
655 This is possible when the host can run code compiled for
656 the target (e.g. host is i686-linux, target is i486-linux).
657 Starting from GCC 4.2, to do this you have to configure explicitly
658 with <samp><span class="option">--enable-bootstrap</span></samp>.
660 <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
661 info manuals and man pages that are built from the .texi files are present
662 in the SVN development tree. When building GCC from that development tree,
663 or from one of our snapshots, those generated files are placed in your
664 build directory, which allows for the source to be in a readonly
667 <p>If you configure with <samp><span class="option">--enable-generated-files-in-srcdir</span></samp> then those
668 generated files will go into the source directory. This is mainly intended
669 for generating release or prerelease tarballs of the GCC sources, since it
670 is not a requirement that the users of source releases to have flex, Bison,
673 <br><dt><code>--enable-version-specific-runtime-libs</code><dd>Specify
674 that runtime libraries should be installed in the compiler specific
675 subdirectory (<samp><var>libdir</var><span class="file">/gcc</span></samp>) rather than the usual places. In
676 addition, ‘<samp><span class="samp">libstdc++</span></samp>’'s include files will be installed into
677 <samp><var>libdir</var></samp> unless you overruled it by using
678 <samp><span class="option">--with-gxx-include-dir=</span><var>dirname</var></samp>. Using this option is
679 particularly useful if you intend to use several versions of GCC in
680 parallel. This is currently supported by ‘<samp><span class="samp">libgfortran</span></samp>’,
681 ‘<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>’.
683 <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
684 their runtime libraries should be built. For a list of valid values for
685 <var>langN</var> you can issue the following command in the
686 <samp><span class="file">gcc</span></samp> directory of your GCC source tree:<br>
687 <pre class="smallexample"> grep language= */config-lang.in
689 <p>Currently, you can use any of the following:
690 <code>all</code>, <code>ada</code>, <code>c</code>, <code>c++</code>, <code>fortran</code>,
691 <code>go</code>, <code>java</code>, <code>objc</code>, <code>obj-c++</code>.
692 Building the Ada compiler has special requirements, see below.
693 If you do not pass this flag, or specify the option <code>all</code>, then all
694 default languages available in the <samp><span class="file">gcc</span></samp> sub-tree will be configured.
695 Ada, Go and Objective-C++ are not default languages; the rest are.
697 <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
698 libraries should be built with the system C compiler during stage 1 of
699 the bootstrap process, rather than only in later stages with the
700 bootstrapped C compiler. The list of valid values is the same as for
701 <samp><span class="option">--enable-languages</span></samp>, and the option <code>all</code> will select all
702 of the languages enabled by <samp><span class="option">--enable-languages</span></samp>. This option is
703 primarily useful for GCC development; for instance, when a development
704 version of the compiler cannot bootstrap due to compiler bugs, or when
705 one is debugging front ends other than the C front end. When this
706 option is used, one can then build the target libraries for the
707 specified languages with the stage-1 compiler by using <samp><span class="command">make
708 stage1-bubble all-target</span></samp>, or run the testsuite on the stage-1 compiler
709 for the specified languages using <samp><span class="command">make stage1-start check-gcc</span></samp>.
711 <br><dt><code>--disable-libada</code><dd>Specify that the run-time libraries and tools used by GNAT should not
712 be built. This can be useful for debugging, or for compatibility with
713 previous Ada build procedures, when it was required to explicitly
714 do a ‘<samp><span class="samp">make -C gcc gnatlib_and_tools</span></samp>’.
716 <br><dt><code>--disable-libssp</code><dd>Specify that the run-time libraries for stack smashing protection
719 <br><dt><code>--disable-libquadmath</code><dd>Specify that the GCC quad-precision math library should not be built.
720 On some systems, the library is required to be linkable when building
721 the Fortran front end, unless <samp><span class="option">--disable-libquadmath-support</span></samp>
724 <br><dt><code>--disable-libquadmath-support</code><dd>Specify that the Fortran front end and <code>libgfortran</code> do not add
725 support for <code>libquadmath</code> on systems supporting it.
727 <br><dt><code>--disable-libgomp</code><dd>Specify that the run-time libraries used by GOMP should not be built.
729 <br><dt><code>--with-dwarf2</code><dd>Specify that the compiler should
730 use DWARF 2 debugging information as the default.
732 <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.
733 These are compilers that are able to generate either 64-bit or 32-bit
734 code. Typically, the corresponding 32-bit target, e.g.
735 powerpc-linux for powerpc64-linux, only generates 32-bit code. This
736 option enables the 32-bit target to be a bi-arch compiler, which is
737 useful when you want a bi-arch compiler that defaults to 32-bit, and
738 you are building a bi-arch or multi-arch binutils in a combined tree.
739 On mips-linux, this will build a tri-arch compiler (ABI o32/n32/64),
741 Currently, this option only affects sparc-linux, powerpc-linux, x86-linux,
742 mips-linux and s390-linux.
744 <br><dt><code>--enable-secureplt</code><dd>This option enables <samp><span class="option">-msecure-plt</span></samp> by default for powerpc-linux.
745 See “RS/6000 and PowerPC Options” in the main manual
747 <br><dt><code>--enable-cld</code><dd>This option enables <samp><span class="option">-mcld</span></samp> by default for 32-bit x86 targets.
748 See “i386 and x86-64 Options” in the main manual
750 <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
751 to look up installations paths in the registry using the following key:
753 <pre class="smallexample"> <code>HKEY_LOCAL_MACHINE\SOFTWARE\Free Software Foundation\</code><var>key</var>
755 <p><var>key</var> defaults to GCC version number, and can be overridden by the
756 <samp><span class="option">--enable-win32-registry=</span><var>key</var></samp> option. Vendors and distributors
757 who use custom installers are encouraged to provide a different key,
758 perhaps one comprised of vendor name and GCC version number, to
759 avoid conflict with existing installations. This feature is enabled
760 by default, and can be disabled by <samp><span class="option">--disable-win32-registry</span></samp>
761 option. This option has no effect on the other hosts.
763 <br><dt><code>--nfp</code><dd>Specify that the machine does not have a floating point unit. This
764 option only applies to ‘<samp><span class="samp">m68k-sun-sunos</span><var>n</var></samp>’. On any other
765 system, <samp><span class="option">--nfp</span></samp> has no effect.
767 <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
768 compiler are built with <samp><span class="option">-Werror</span></samp> in bootstrap stage2 and later.
769 If you don't specify it, <samp><span class="option">-Werror</span></samp> is turned on for the main
770 development trunk. However it defaults to off for release branches and
771 final releases. The specific files which get <samp><span class="option">-Werror</span></samp> are
772 controlled by the Makefiles.
774 <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
775 consistency checks of the requested complexity. This does not change the
776 generated code, but adds error checking within the compiler. This will
777 slow down the compiler and may only work properly if you are building
778 the compiler with GCC. This is ‘<samp><span class="samp">yes</span></samp>’ by default when building
779 from SVN or snapshots, but ‘<samp><span class="samp">release</span></samp>’ for releases. The default
780 for building the stage1 compiler is ‘<samp><span class="samp">yes</span></samp>’. More control
781 over the checks may be had by specifying <var>list</var>. The categories of
782 checks available are ‘<samp><span class="samp">yes</span></samp>’ (most common checks
783 ‘<samp><span class="samp">assert,misc,tree,gc,rtlflag,runtime</span></samp>’), ‘<samp><span class="samp">no</span></samp>’ (no checks at
784 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
785 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>’).
786 Individual checks can be enabled with these flags ‘<samp><span class="samp">assert</span></samp>’,
787 ‘<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>’,
788 ‘<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>’.
790 <p>The ‘<samp><span class="samp">valgrind</span></samp>’ check requires the external <samp><span class="command">valgrind</span></samp>
791 simulator, available from <a href="http://valgrind.org/">http://valgrind.org/</a>. The
792 ‘<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.
793 To disable all checking, ‘<samp><span class="samp">--disable-checking</span></samp>’ or
794 ‘<samp><span class="samp">--enable-checking=none</span></samp>’ must be explicitly requested. Disabling
795 assertions will make the compiler and runtime slightly faster but
796 increase the risk of undetected internal errors causing wrong code to be
799 <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
800 compiler will be built with ‘<samp><span class="samp">yes</span></samp>’ checking enabled, otherwise
801 the stage1 checking flags are the same as specified by
802 <samp><span class="option">--enable-checking</span></samp>. To build the stage1 compiler with
803 different checking options use <samp><span class="option">--enable-stage1-checking</span></samp>.
804 The list of checking options is the same as for <samp><span class="option">--enable-checking</span></samp>.
805 If your system is too slow or too small to bootstrap a released compiler
806 with checking for stage1 enabled, you can use ‘<samp><span class="samp">--disable-stage1-checking</span></samp>’
807 to disable checking for the stage1 compiler.
809 <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
810 information, every time it is run. This is for internal development
811 purposes, and only works when the compiler is being built with gcc. The
812 <var>level</var> argument controls whether the compiler is built optimized or
813 not, values are ‘<samp><span class="samp">opt</span></samp>’ and ‘<samp><span class="samp">noopt</span></samp>’. For coverage analysis you
814 want to disable optimization, for performance analysis you want to
815 enable optimization. When coverage is enabled, the default level is
816 without optimization.
818 <br><dt><code>--enable-gather-detailed-mem-stats</code><dd>When this option is specified more detailed information on memory
819 allocation is gathered. This information is printed when using
820 <samp><span class="option">-fmem-report</span></samp>.
822 <br><dt><code>--with-gc</code><dt><code>--with-gc=</code><var>choice</var><dd>With this option you can specify the garbage collector implementation
823 used during the compilation process. <var>choice</var> can be one of
824 ‘<samp><span class="samp">page</span></samp>’ and ‘<samp><span class="samp">zone</span></samp>’, where ‘<samp><span class="samp">page</span></samp>’ is the default.
826 <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),
827 which lets GCC output diagnostics in languages other than American
828 English. Native Language Support is enabled by default if not doing a
829 canadian cross build. The <samp><span class="option">--disable-nls</span></samp> option disables NLS.
831 <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
832 procedure to prefer its copy of GNU <samp><span class="command">gettext</span></samp>.
834 <br><dt><code>--with-catgets</code><dd>If NLS is enabled, and if the host lacks <code>gettext</code> but has the
835 inferior <code>catgets</code> interface, the GCC build procedure normally
836 ignores <code>catgets</code> and instead uses GCC's copy of the GNU
837 <code>gettext</code> library. The <samp><span class="option">--with-catgets</span></samp> option causes the
838 build procedure to use the host's <code>catgets</code> in this situation.
840 <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
841 libiconv library files in <samp><var>dir</var><span class="file">/lib</span></samp>.
843 <br><dt><code>--enable-obsolete</code><dd>Enable configuration for an obsoleted system. If you attempt to
844 configure GCC for a system (build, host, or target) which has been
845 obsoleted, and you do not specify this flag, configure will halt with an
848 <p>All support for systems which have been obsoleted in one release of GCC
849 is removed entirely in the next major release, unless someone steps
850 forward to maintain the port.
852 <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
853 that is in the IEEE 754-2008 standard. This is enabled by default only
854 on PowerPC, i386, and x86_64 GNU/Linux systems. Other systems may also
855 support it, but require the user to specifically enable it. You can
856 optionally control which decimal floating point format is used (either
857 ‘<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)
858 format is default on i386 and x86_64 systems, and the ‘<samp><span class="samp">dpd</span></samp>’
859 (densely packed decimal) format is default on PowerPC systems.
861 <br><dt><code>--enable-fixed-point</code><dt><code>--disable-fixed-point</code><dd>Enable (or disable) support for C fixed-point arithmetic.
862 This option is enabled by default for some targets (such as MIPS) which
863 have hardware-support for fixed-point operations. On other targets, you
864 may enable this option manually.
866 <br><dt><code>--with-long-double-128</code><dd>Specify if <code>long double</code> type should be 128-bit by default on selected
867 GNU/Linux architectures. If using <code>--without-long-double-128</code>,
868 <code>long double</code> will be by default 64-bit, the same as <code>double</code> type.
869 When neither of these configure options are used, the default will be
870 128-bit <code>long double</code> when built against GNU C Library 2.4 and later,
871 64-bit <code>long double</code> otherwise.
873 <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
874 library and/or the MPC library installed in a standard location and
875 do not have their sources present in the GCC source tree then you
876 can explicitly specify the directory where they are installed
877 (‘<samp><span class="samp">--with-gmp=</span><var>gmpinstalldir</var></samp>’,
878 ‘<samp><span class="samp">--with-mpfr=</span><var>mpfrinstalldir</var></samp>’,
879 ‘<samp><span class="samp">--with-mpc=</span><var>mpcinstalldir</var></samp>’). The
880 <samp><span class="option">--with-gmp=</span><var>gmpinstalldir</var></samp> option is shorthand for
881 <samp><span class="option">--with-gmp-lib=</span><var>gmpinstalldir</var><span class="option">/lib</span></samp> and
882 <samp><span class="option">--with-gmp-include=</span><var>gmpinstalldir</var><span class="option">/include</span></samp>. Likewise the
883 <samp><span class="option">--with-mpfr=</span><var>mpfrinstalldir</var></samp> option is shorthand for
884 <samp><span class="option">--with-mpfr-lib=</span><var>mpfrinstalldir</var><span class="option">/lib</span></samp> and
885 <samp><span class="option">--with-mpfr-include=</span><var>mpfrinstalldir</var><span class="option">/include</span></samp>, also the
886 <samp><span class="option">--with-mpc=</span><var>mpcinstalldir</var></samp> option is shorthand for
887 <samp><span class="option">--with-mpc-lib=</span><var>mpcinstalldir</var><span class="option">/lib</span></samp> and
888 <samp><span class="option">--with-mpc-include=</span><var>mpcinstalldir</var><span class="option">/include</span></samp>. If these
889 shorthand assumptions are not correct, you can use the explicit
890 include and lib options directly. You might also need to ensure the
891 shared libraries can be found by the dynamic linker when building and
892 using GCC, for example by setting the runtime shared library path
893 variable (<samp><span class="env">LD_LIBRARY_PATH</span></samp> on GNU/Linux and Solaris systems).
895 <p>These flags are applicable to the host platform only. When building
896 a cross compiler, they will not be used to configure target libraries.
898 <br><dt><code>--with-ppl=</code><var>pathname</var><dt><code>--with-ppl-include=</code><var>pathname</var><dt><code>--with-ppl-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 PPL (the Parma Polyhedra Library) and the CLooG
899 libraries installed in a standard location and you want to build GCC,
900 you can explicitly specify the directory where they are installed
901 (‘<samp><span class="samp">--with-ppl=</span><var>pplinstalldir</var></samp>’,
902 ‘<samp><span class="samp">--with-cloog=</span><var>clooginstalldir</var></samp>’). The
903 <samp><span class="option">--with-ppl=</span><var>pplinstalldir</var></samp> option is shorthand for
904 <samp><span class="option">--with-ppl-lib=</span><var>pplinstalldir</var><span class="option">/lib</span></samp> and
905 <samp><span class="option">--with-ppl-include=</span><var>pplinstalldir</var><span class="option">/include</span></samp>. Likewise the
906 <samp><span class="option">--with-cloog=</span><var>clooginstalldir</var></samp> option is shorthand for
907 <samp><span class="option">--with-cloog-lib=</span><var>clooginstalldir</var><span class="option">/lib</span></samp> and
908 <samp><span class="option">--with-cloog-include=</span><var>clooginstalldir</var><span class="option">/include</span></samp>. If these
909 shorthand assumptions are not correct, you can use the explicit
910 include and lib options directly.
912 <p>These flags are applicable to the host platform only. When building
913 a cross compiler, they will not be used to configure target libraries.
915 <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
916 to specify how the linker should find the standard C++ library used
917 internally by PPL. Typical values of <var>linker-args</var> might be
918 ‘<samp><span class="samp">-lstdc++</span></samp>’ or ‘<samp><span class="samp">-Wl,-Bstatic,-lstdc++,-Bdynamic -lm</span></samp>’. If you are
919 linking with a shared copy of PPL, you probably do not need this
920 option; shared library dependencies will cause the linker to search
921 for the standard C++ library automatically.
923 <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
924 stage 1 of GCC. These are also used when linking GCC if configured with
925 <samp><span class="option">--disable-bootstrap</span></samp>. By default no special flags are used.
927 <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
928 of GCC. These are also used when linking GCC if configured with
929 <samp><span class="option">--disable-bootstrap</span></samp>. The default is the argument to
930 <samp><span class="option">--with-host-libstdcxx</span></samp>, if specified.
932 <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
933 stage 2 and later when bootstrapping GCC. If neither –with-boot-libs
934 nor –with-host-libstdcxx is set to a value, then the default is
935 ‘<samp><span class="samp">-static-libstdc++ -static-libgcc</span></samp>’.
937 <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
938 and later when bootstrapping GCC. The default is the argument to
939 <samp><span class="option">--with-host-libstdcxx</span></samp>, if specified.
941 <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
942 building runtime libraries. ‘<samp><var>map</var></samp>’ is a space-separated
943 list of maps of the form ‘<samp><var>old</var><span class="samp">=</span><var>new</var></samp>’.
945 <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
946 links (links performed without the <samp><span class="option">-r</span></samp> or <samp><span class="option">--relocatable</span></samp>
947 option), if the linker supports it. If you specify
948 <samp><span class="option">--enable-linker-build-id</span></samp>, but your linker does not
949 support <samp><span class="option">--build-id</span></samp> option, a warning is issued and the
950 <samp><span class="option">--enable-linker-build-id</span></samp> option is ignored. The default is off.
952 <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
953 linker for all final links. <var>choice</var> can be one of
954 ‘<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.
956 <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
957 static data members and inline function local statics. Enabled by
958 default for a native toolchain with an assembler that accepts it and
959 GLIBC 2.11 or above, otherwise disabled.
961 <br><dt><code>--enable-lto</code><dt><code>--disable-lto</code><dd>Enable support for link-time optimization (LTO). This is enabled by
962 default, and may be disabled using <samp><span class="option">--disable-lto</span></samp>.
964 <br><dt><code>--with-plugin-ld=</code><var>pathname</var><dd>Enable an alternate linker to be used at link-time optimization (LTO)
965 link time when <samp><span class="option">-fuse-linker-plugin</span></samp> is enabled.
966 This linker should have plugin support such as gold starting with
967 version 2.20 or GNU ld starting with version 2.21.
968 See <samp><span class="option">-fuse-linker-plugin</span></samp> for details.
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-build-time-tools=</code><var>dir</var><dd>Specifies where to find the set of target tools (assembler, linker, etc.)
1040 that will be used while building GCC itself. This option can be useful
1041 if the directory layouts are different between the system you are building
1042 GCC on, and the system where you will deploy it.
1044 <p>For example, on an ‘<samp><span class="samp">ia64-hp-hpux</span></samp>’ system, you may have the GNU
1045 assembler and linker in <samp><span class="file">/usr/bin</span></samp>, and the native tools in a
1046 different path, and build a toolchain that expects to find the
1047 native tools in <samp><span class="file">/usr/bin</span></samp>.
1049 <p>When you use this option, you should ensure that <var>dir</var> includes
1050 <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>,
1051 <samp><span class="command">ranlib</span></samp> and <samp><span class="command">strip</span></samp> if necessary, and possibly
1052 <samp><span class="command">objdump</span></samp>. Otherwise, GCC may use an inconsistent set of
1056 <h4 class="subheading"><a name="TOC4"></a>Java-Specific Options</h4>
1058 <p>The following option applies to the build of the Java front end.
1061 <dt><code>--disable-libgcj</code><dd>Specify that the run-time libraries
1062 used by GCJ should not be built. This is useful in case you intend
1063 to use GCJ with some other run-time, or you're going to install it
1064 separately, or it just happens not to build on your particular
1065 machine. In general, if the Java front end is enabled, the GCJ
1066 libraries will be enabled too, unless they're known to not work on
1067 the target platform. If GCJ is enabled but ‘<samp><span class="samp">libgcj</span></samp>’ isn't built, you
1068 may need to port it; in this case, before modifying the top-level
1069 <samp><span class="file">configure.in</span></samp> so that ‘<samp><span class="samp">libgcj</span></samp>’ is enabled by default on this platform,
1070 you may use <samp><span class="option">--enable-libgcj</span></samp> to override the default.
1074 <p>The following options apply to building ‘<samp><span class="samp">libgcj</span></samp>’.
1076 <h5 class="subsubheading"><a name="TOC5"></a>General Options</h5>
1079 <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
1080 <samp><span class="file">.java</span></samp> source files to <samp><span class="file">.class</span></samp>. Instead, it will use the
1081 <samp><span class="file">.class</span></samp> files from the source tree. If you use this option you
1082 must have executables named <samp><span class="command">ecj1</span></samp> and <samp><span class="command">gjavah</span></samp> in your path
1083 for use by the build. You must use this option if you intend to
1084 modify any <samp><span class="file">.java</span></samp> files in <samp><span class="file">libjava</span></samp>.
1086 <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
1087 ‘<samp><span class="samp">java.home</span></samp>’ system property. It is also used to set
1088 ‘<samp><span class="samp">sun.boot.class.path</span></samp>’ to <samp><var>dirname</var><span class="file">/lib/rt.jar</span></samp>. By
1089 default ‘<samp><span class="samp">java.home</span></samp>’ is set to <samp><var>prefix</var></samp> and
1090 ‘<samp><span class="samp">sun.boot.class.path</span></samp>’ to
1091 <samp><var>datadir</var><span class="file">/java/libgcj-</span><var>version</var><span class="file">.jar</span></samp>.
1093 <br><dt><code>--with-ecj-jar=</code><var>filename</var><dd>This option can be used to specify the location of an external jar
1094 file containing the Eclipse Java compiler. A specially modified
1095 version of this compiler is used by <samp><span class="command">gcj</span></samp> to parse
1096 <samp><span class="file">.java</span></samp> source files. If this option is given, the
1097 ‘<samp><span class="samp">libjava</span></samp>’ build will create and install an <samp><span class="file">ecj1</span></samp> executable
1098 which uses this jar file at runtime.
1100 <p>If this option is not given, but an <samp><span class="file">ecj.jar</span></samp> file is found in
1101 the topmost source tree at configure time, then the ‘<samp><span class="samp">libgcj</span></samp>’
1102 build will create and install <samp><span class="file">ecj1</span></samp>, and will also install the
1103 discovered <samp><span class="file">ecj.jar</span></samp> into a suitable place in the install tree.
1105 <p>If <samp><span class="file">ecj1</span></samp> is not installed, then the user will have to supply one
1106 on his path in order for <samp><span class="command">gcj</span></samp> to properly parse <samp><span class="file">.java</span></samp>
1107 source files. A suitable jar is available from
1108 <a href="ftp://sourceware.org/pub/java/">ftp://sourceware.org/pub/java/</a>.
1110 <br><dt><code>--disable-getenv-properties</code><dd>Don't set system properties from <samp><span class="env">GCJ_PROPERTIES</span></samp>.
1112 <br><dt><code>--enable-hash-synchronization</code><dd>Use a global hash table for monitor locks. Ordinarily,
1113 ‘<samp><span class="samp">libgcj</span></samp>’'s ‘<samp><span class="samp">configure</span></samp>’ script automatically makes
1114 the correct choice for this option for your platform. Only use
1115 this if you know you need the library to be configured differently.
1117 <br><dt><code>--enable-interpreter</code><dd>Enable the Java interpreter. The interpreter is automatically
1118 enabled by default on all platforms that support it. This option
1119 is really only useful if you want to disable the interpreter
1120 (using <samp><span class="option">--disable-interpreter</span></samp>).
1122 <br><dt><code>--disable-java-net</code><dd>Disable java.net. This disables the native part of java.net only,
1123 using non-functional stubs for native method implementations.
1125 <br><dt><code>--disable-jvmpi</code><dd>Disable JVMPI support.
1127 <br><dt><code>--disable-libgcj-bc</code><dd>Disable BC ABI compilation of certain parts of libgcj. By default,
1128 some portions of libgcj are compiled with <samp><span class="option">-findirect-dispatch</span></samp>
1129 and <samp><span class="option">-fno-indirect-classes</span></samp>, allowing them to be overridden at
1132 <p>If <samp><span class="option">--disable-libgcj-bc</span></samp> is specified, libgcj is built without
1133 these options. This allows the compile-time linker to resolve
1134 dependencies when statically linking to libgcj. However it makes it
1135 impossible to override the affected portions of libgcj at run-time.
1137 <br><dt><code>--enable-reduced-reflection</code><dd>Build most of libgcj with <samp><span class="option">-freduced-reflection</span></samp>. This reduces
1138 the size of libgcj at the expense of not being able to do accurate
1139 reflection on the classes it contains. This option is safe if you
1140 know that code using libgcj will never use reflection on the standard
1141 runtime classes in libgcj (including using serialization, RMI or CORBA).
1143 <br><dt><code>--with-ecos</code><dd>Enable runtime eCos target support.
1145 <br><dt><code>--without-libffi</code><dd>Don't use ‘<samp><span class="samp">libffi</span></samp>’. This will disable the interpreter and JNI
1146 support as well, as these require ‘<samp><span class="samp">libffi</span></samp>’ to work.
1148 <br><dt><code>--enable-libgcj-debug</code><dd>Enable runtime debugging code.
1150 <br><dt><code>--enable-libgcj-multifile</code><dd>If specified, causes all <samp><span class="file">.java</span></samp> source files to be
1151 compiled into <samp><span class="file">.class</span></samp> files in one invocation of
1152 ‘<samp><span class="samp">gcj</span></samp>’. This can speed up build time, but is more
1153 resource-intensive. If this option is unspecified or
1154 disabled, ‘<samp><span class="samp">gcj</span></samp>’ is invoked once for each <samp><span class="file">.java</span></samp>
1155 file to compile into a <samp><span class="file">.class</span></samp> file.
1157 <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>.
1159 <br><dt><code>--enable-sjlj-exceptions</code><dd>Force use of the <code>setjmp</code>/<code>longjmp</code>-based scheme for exceptions.
1160 ‘<samp><span class="samp">configure</span></samp>’ ordinarily picks the correct value based on the platform.
1161 Only use this option if you are sure you need a different setting.
1163 <br><dt><code>--with-system-zlib</code><dd>Use installed ‘<samp><span class="samp">zlib</span></samp>’ rather than that included with GCC.
1165 <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
1166 characters and the Win32 API.
1168 <br><dt><code>--enable-java-home</code><dd>If enabled, this creates a JPackage compatible SDK environment during install.
1169 Note that if –enable-java-home is used, –with-arch-directory=ARCH must also
1172 <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
1173 environment created when –enable-java-home is passed. Typical names for this
1174 directory include i386, amd64, ia64, etc.
1176 <br><dt><code>--with-os-directory=DIR</code><dd>Specifies the OS directory for the SDK include directory. This is set to auto
1177 detect, and is typically 'linux'.
1179 <br><dt><code>--with-origin-name=NAME</code><dd>Specifies the JPackage origin name. This defaults to the 'gcj' in
1182 <br><dt><code>--with-arch-suffix=SUFFIX</code><dd>Specifies the suffix for the sdk directory. Defaults to the empty string.
1183 Examples include '.x86_64' in 'java-1.5.0-gcj-1.5.0.0.x86_64'.
1185 <br><dt><code>--with-jvm-root-dir=DIR</code><dd>Specifies where to install the SDK. Default is $(prefix)/lib/jvm.
1187 <br><dt><code>--with-jvm-jar-dir=DIR</code><dd>Specifies where to install jars. Default is $(prefix)/lib/jvm-exports.
1189 <br><dt><code>--with-python-dir=DIR</code><dd>Specifies where to install the Python modules used for aot-compile. DIR should
1190 not include the prefix used in installation. For example, if the Python modules
1191 are to be installed in /usr/lib/python2.5/site-packages, then
1192 –with-python-dir=/lib/python2.5/site-packages should be passed. If this is
1193 not specified, then the Python modules are installed in $(prefix)/share/python.
1195 <br><dt><code>--enable-aot-compile-rpm</code><dd>Adds aot-compile-rpm to the list of installed scripts.
1197 <br><dt><code>--enable-browser-plugin</code><dd>Build the gcjwebplugin web browser plugin.
1199 <br><dt><code>--enable-static-libjava</code><dd>Build static libraries in libjava. The default is to only build shared
1203 <dt><code>ansi</code><dd>Use the single-byte <code>char</code> and the Win32 A functions natively,
1204 translating to and from UNICODE when using these functions. If
1205 unspecified, this is the default.
1207 <br><dt><code>unicows</code><dd>Use the <code>WCHAR</code> and Win32 W functions natively. Adds
1208 <code>-lunicows</code> to <samp><span class="file">libgcj.spec</span></samp> to link with ‘<samp><span class="samp">libunicows</span></samp>’.
1209 <samp><span class="file">unicows.dll</span></samp> needs to be deployed on Microsoft Windows 9X machines
1210 running built executables. <samp><span class="file">libunicows.a</span></samp>, an open-source
1211 import library around Microsoft's <code>unicows.dll</code>, is obtained from
1212 <a href="http://libunicows.sourceforge.net/">http://libunicows.sourceforge.net/</a>, which also gives details
1213 on getting <samp><span class="file">unicows.dll</span></samp> from Microsoft.
1215 <br><dt><code>unicode</code><dd>Use the <code>WCHAR</code> and Win32 W functions natively. Does <em>not</em>
1216 add <code>-lunicows</code> to <samp><span class="file">libgcj.spec</span></samp>. The built executables will
1217 only run on Microsoft Windows NT and above.
1221 <h5 class="subsubheading"><a name="TOC6"></a>AWT-Specific Options</h5>
1224 <dt><code>--with-x</code><dd>Use the X Window System.
1226 <br><dt><code>--enable-java-awt=PEER(S)</code><dd>Specifies the AWT peer library or libraries to build alongside
1227 ‘<samp><span class="samp">libgcj</span></samp>’. If this option is unspecified or disabled, AWT
1228 will be non-functional. Current valid values are <samp><span class="option">gtk</span></samp> and
1229 <samp><span class="option">xlib</span></samp>. Multiple libraries should be separated by a
1230 comma (i.e. <samp><span class="option">--enable-java-awt=gtk,xlib</span></samp>).
1232 <br><dt><code>--enable-gtk-cairo</code><dd>Build the cairo Graphics2D implementation on GTK.
1234 <br><dt><code>--enable-java-gc=TYPE</code><dd>Choose garbage collector. Defaults to <samp><span class="option">boehm</span></samp> if unspecified.
1236 <br><dt><code>--disable-gtktest</code><dd>Do not try to compile and run a test GTK+ program.
1238 <br><dt><code>--disable-glibtest</code><dd>Do not try to compile and run a test GLIB program.
1240 <br><dt><code>--with-libart-prefix=PFX</code><dd>Prefix where libart is installed (optional).
1242 <br><dt><code>--with-libart-exec-prefix=PFX</code><dd>Exec prefix where libart is installed (optional).
1244 <br><dt><code>--disable-libarttest</code><dd>Do not try to compile and run a test libart program.
1248 <h5 class="subsubheading"><a name="TOC7"></a>Overriding <samp><span class="command">configure</span></samp> test results</h5>
1250 <p>Sometimes, it might be necessary to override the result of some
1251 <samp><span class="command">configure</span></samp> test, for example in order to ease porting to a new
1252 system or work around a bug in a test. The toplevel <samp><span class="command">configure</span></samp>
1253 script provides three variables for this:
1256 <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>
1259 <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>
1262 <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>
1267 <p>In order to avoid shell and <samp><span class="command">make</span></samp> quoting issues for complex
1268 overrides, you can pass a setting for <samp><span class="env">CONFIG_SITE</span></samp> and set
1269 variables in the site file.
1272 <p><a href="./index.html">Return to the GCC Installation page</a>
1274 <!-- ***Building**************************************************************** -->
1275 <!-- ***Testing***************************************************************** -->
1276 <!-- ***Final install*********************************************************** -->
1277 <!-- ***Binaries**************************************************************** -->
1278 <!-- ***Specific**************************************************************** -->
1279 <!-- ***Old documentation****************************************************** -->
1280 <!-- ***GFDL******************************************************************** -->
1281 <!-- *************************************************************************** -->
1282 <!-- Part 6 The End of the Document -->