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1449 lines
98 KiB
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<html lang="en">
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<head>
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<title>Installing GCC: Configuration</title>
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any later version published by the Free Software Foundation; with no
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</head>
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<body>
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<h1 class="settitle">Installing GCC: Configuration</h1>
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<a name="index-Configuration-1"></a><a name="index-Installing-GCC_003a-Configuration-2"></a>
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Like most GNU software, GCC must be configured before it can be built.
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This document describes the recommended configuration procedure
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for both native and cross targets.
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<p>We use <var>srcdir</var> to refer to the toplevel source directory for
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GCC; we use <var>objdir</var> to refer to the toplevel build/object directory.
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<p>If you obtained the sources via SVN, <var>srcdir</var> must refer to the top
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<samp><span class="file">gcc</span></samp> directory, the one where the <samp><span class="file">MAINTAINERS</span></samp> file can be
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found, and not its <samp><span class="file">gcc</span></samp> subdirectory, otherwise the build will fail.
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<p>If either <var>srcdir</var> or <var>objdir</var> is located on an automounted NFS
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file system, the shell's built-in <samp><span class="command">pwd</span></samp> command will return
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temporary pathnames. Using these can lead to various sorts of build
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problems. To avoid this issue, set the <samp><span class="env">PWDCMD</span></samp> environment
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variable to an automounter-aware <samp><span class="command">pwd</span></samp> command, e.g.,
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<samp><span class="command">pawd</span></samp> or ‘<samp><span class="samp">amq -w</span></samp>’, during the configuration and build
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phases.
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<p>First, we <strong>highly</strong> recommend that GCC be built into a
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separate directory from the sources which does <strong>not</strong> reside
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within the source tree. This is how we generally build GCC; building
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where <var>srcdir</var> == <var>objdir</var> should still work, but doesn't
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get extensive testing; building where <var>objdir</var> is a subdirectory
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of <var>srcdir</var> is unsupported.
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<p>If you have previously built GCC in the same directory for a
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different target machine, do ‘<samp><span class="samp">make distclean</span></samp>’ to delete all files
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that might be invalid. One of the files this deletes is <samp><span class="file">Makefile</span></samp>;
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if ‘<samp><span class="samp">make distclean</span></samp>’ complains that <samp><span class="file">Makefile</span></samp> does not exist
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or issues a message like “don't know how to make distclean” it probably
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means that the directory is already suitably clean. However, with the
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recommended method of building in a separate <var>objdir</var>, you should
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simply use a different <var>objdir</var> for each target.
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<p>Second, when configuring a native system, either <samp><span class="command">cc</span></samp> or
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<samp><span class="command">gcc</span></samp> must be in your path or you must set <samp><span class="env">CC</span></samp> in
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your environment before running configure. Otherwise the configuration
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scripts may fail.
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<p>To configure GCC:
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<pre class="smallexample"> % mkdir <var>objdir</var>
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% cd <var>objdir</var>
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% <var>srcdir</var>/configure [<var>options</var>] [<var>target</var>]
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</pre>
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<h3 class="heading"><a name="TOC0"></a>Distributor options</h3>
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<p>If you will be distributing binary versions of GCC, with modifications
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to the source code, you should use the options described in this
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section to make clear that your version contains modifications.
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<dl>
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<dt><code>--with-pkgversion=</code><var>version</var><dd>Specify a string that identifies your package. You may wish
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to include a build number or build date. This version string will be
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included in the output of <samp><span class="command">gcc --version</span></samp>. This suffix does
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not replace the default version string, only the ‘<samp><span class="samp">GCC</span></samp>’ part.
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<p>The default value is ‘<samp><span class="samp">GCC</span></samp>’.
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<br><dt><code>--with-bugurl=</code><var>url</var><dd>Specify the URL that users should visit if they wish to report a bug.
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You are of course welcome to forward bugs reported to you to the FSF,
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if you determine that they are not bugs in your modifications.
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<p>The default value refers to the FSF's GCC bug tracker.
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</dl>
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<h3 class="heading"><a name="TOC1"></a>Target specification</h3>
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<ul>
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<li>GCC has code to correctly determine the correct value for <var>target</var>
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for nearly all native systems. Therefore, we highly recommend you do
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not provide a configure target when configuring a native compiler.
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<li><var>target</var> must be specified as <samp><span class="option">--target=</span><var>target</var></samp>
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when configuring a cross compiler; examples of valid targets would be
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m68k-elf, sh-elf, etc.
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<li>Specifying just <var>target</var> instead of <samp><span class="option">--target=</span><var>target</var></samp>
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implies that the host defaults to <var>target</var>.
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</ul>
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<h3 class="heading"><a name="TOC2"></a>Options specification</h3>
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<p>Use <var>options</var> to override several configure time options for
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GCC. A list of supported <var>options</var> follows; ‘<samp><span class="samp">configure
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--help</span></samp>’ may list other options, but those not listed below may not
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work and should not normally be used.
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<p>Note that each <samp><span class="option">--enable</span></samp> option has a corresponding
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<samp><span class="option">--disable</span></samp> option and that each <samp><span class="option">--with</span></samp> option has a
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corresponding <samp><span class="option">--without</span></samp> option.
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<dl>
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<dt><code>--prefix=</code><var>dirname</var><dd>Specify the toplevel installation
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directory. This is the recommended way to install the tools into a directory
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other than the default. The toplevel installation directory defaults to
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<samp><span class="file">/usr/local</span></samp>.
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<p>We <strong>highly</strong> recommend against <var>dirname</var> being the same or a
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subdirectory of <var>objdir</var> or vice versa. If specifying a directory
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beneath a user's home directory tree, some shells will not expand
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<var>dirname</var> correctly if it contains the ‘<samp><span class="samp">~</span></samp>’ metacharacter; use
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<samp><span class="env">$HOME</span></samp> instead.
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<p>The following standard <samp><span class="command">autoconf</span></samp> options are supported. Normally you
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should not need to use these options.
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<dl>
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<dt><code>--exec-prefix=</code><var>dirname</var><dd>Specify the toplevel installation directory for architecture-dependent
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files. The default is <samp><var>prefix</var></samp>.
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<br><dt><code>--bindir=</code><var>dirname</var><dd>Specify the installation directory for the executables called by users
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(such as <samp><span class="command">gcc</span></samp> and <samp><span class="command">g++</span></samp>). The default is
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<samp><var>exec-prefix</var><span class="file">/bin</span></samp>.
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<br><dt><code>--libdir=</code><var>dirname</var><dd>Specify the installation directory for object code libraries and
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internal data files of GCC. The default is <samp><var>exec-prefix</var><span class="file">/lib</span></samp>.
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<br><dt><code>--libexecdir=</code><var>dirname</var><dd>Specify the installation directory for internal executables of GCC.
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The default is <samp><var>exec-prefix</var><span class="file">/libexec</span></samp>.
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<br><dt><code>--with-slibdir=</code><var>dirname</var><dd>Specify the installation directory for the shared libgcc library. The
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default is <samp><var>libdir</var></samp>.
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<br><dt><code>--datarootdir=</code><var>dirname</var><dd>Specify the root of the directory tree for read-only architecture-independent
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data files referenced by GCC. The default is <samp><var>prefix</var><span class="file">/share</span></samp>.
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<br><dt><code>--infodir=</code><var>dirname</var><dd>Specify the installation directory for documentation in info format.
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The default is <samp><var>datarootdir</var><span class="file">/info</span></samp>.
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<br><dt><code>--datadir=</code><var>dirname</var><dd>Specify the installation directory for some architecture-independent
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data files referenced by GCC. The default is <samp><var>datarootdir</var></samp>.
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<br><dt><code>--docdir=</code><var>dirname</var><dd>Specify the installation directory for documentation files (other
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than Info) for GCC. The default is <samp><var>datarootdir</var><span class="file">/doc</span></samp>.
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<br><dt><code>--htmldir=</code><var>dirname</var><dd>Specify the installation directory for HTML documentation files.
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The default is <samp><var>docdir</var></samp>.
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<br><dt><code>--pdfdir=</code><var>dirname</var><dd>Specify the installation directory for PDF documentation files.
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The default is <samp><var>docdir</var></samp>.
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<br><dt><code>--mandir=</code><var>dirname</var><dd>Specify the installation directory for manual pages. The default is
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<samp><var>datarootdir</var><span class="file">/man</span></samp>. (Note that the manual pages are only extracts
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from the full GCC manuals, which are provided in Texinfo format. The manpages
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are derived by an automatic conversion process from parts of the full
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manual.)
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<br><dt><code>--with-gxx-include-dir=</code><var>dirname</var><dd>Specify
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the installation directory for G++ header files. The default depends
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on other configuration options, and differs between cross and native
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configurations.
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<br><dt><code>--with-specs=</code><var>specs</var><dd>Specify additional command line driver SPECS.
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This can be useful if you need to turn on a non-standard feature by
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default without modifying the compiler's source code, for instance
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<samp><span class="option">--with-specs=%{!fcommon:%{!fno-common:-fno-common}}</span></samp>.
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See “Spec Files” in the main manual
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</dl>
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<br><dt><code>--program-prefix=</code><var>prefix</var><dd>GCC supports some transformations of the names of its programs when
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installing them. This option prepends <var>prefix</var> to the names of
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programs to install in <var>bindir</var> (see above). For example, specifying
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<samp><span class="option">--program-prefix=foo-</span></samp> would result in ‘<samp><span class="samp">gcc</span></samp>’
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being installed as <samp><span class="file">/usr/local/bin/foo-gcc</span></samp>.
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<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>
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(see above). For example, specifying <samp><span class="option">--program-suffix=-3.1</span></samp>
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would result in ‘<samp><span class="samp">gcc</span></samp>’ being installed as
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<samp><span class="file">/usr/local/bin/gcc-3.1</span></samp>.
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<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
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of programs to install in <var>bindir</var> (see above). <var>pattern</var> has to
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consist of one or more basic ‘<samp><span class="samp">sed</span></samp>’ editing commands, separated by
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semicolons. For example, if you want the ‘<samp><span class="samp">gcc</span></samp>’ program name to be
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transformed to the installed program <samp><span class="file">/usr/local/bin/myowngcc</span></samp> and
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the ‘<samp><span class="samp">g++</span></samp>’ program name to be transformed to
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<samp><span class="file">/usr/local/bin/gspecial++</span></samp> without changing other program names,
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you could use the pattern
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<samp><span class="option">--program-transform-name='s/^gcc$/myowngcc/; s/^g++$/gspecial++/'</span></samp>
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to achieve this effect.
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<p>All three options can be combined and used together, resulting in more
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complex conversion patterns. As a basic rule, <var>prefix</var> (and
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<var>suffix</var>) are prepended (appended) before further transformations
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can happen with a special transformation script <var>pattern</var>.
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<p>As currently implemented, this option only takes effect for native
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builds; cross compiler binaries' names are not transformed even when a
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transformation is explicitly asked for by one of these options.
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<p>For native builds, some of the installed programs are also installed
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with the target alias in front of their name, as in
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‘<samp><span class="samp">i686-pc-linux-gnu-gcc</span></samp>’. All of the above transformations happen
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before the target alias is prepended to the name—so, specifying
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<samp><span class="option">--program-prefix=foo-</span></samp> and <samp><span class="option">program-suffix=-3.1</span></samp>, the
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resulting binary would be installed as
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<samp><span class="file">/usr/local/bin/i686-pc-linux-gnu-foo-gcc-3.1</span></samp>.
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<p>As a last shortcoming, none of the installed Ada programs are
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transformed yet, which will be fixed in some time.
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<br><dt><code>--with-local-prefix=</code><var>dirname</var><dd>Specify the
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installation directory for local include files. The default is
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<samp><span class="file">/usr/local</span></samp>. Specify this option if you want the compiler to
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search directory <samp><var>dirname</var><span class="file">/include</span></samp> for locally installed
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header files <em>instead</em> of <samp><span class="file">/usr/local/include</span></samp>.
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<p>You should specify <samp><span class="option">--with-local-prefix</span></samp> <strong>only</strong> if your
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site has a different convention (not <samp><span class="file">/usr/local</span></samp>) for where to put
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site-specific files.
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<p>The default value for <samp><span class="option">--with-local-prefix</span></samp> is <samp><span class="file">/usr/local</span></samp>
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regardless of the value of <samp><span class="option">--prefix</span></samp>. Specifying
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<samp><span class="option">--prefix</span></samp> has no effect on which directory GCC searches for
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local header files. This may seem counterintuitive, but actually it is
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logical.
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<p>The purpose of <samp><span class="option">--prefix</span></samp> is to specify where to <em>install
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GCC</em>. The local header files in <samp><span class="file">/usr/local/include</span></samp>—if you put
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any in that directory—are not part of GCC. They are part of other
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programs—perhaps many others. (GCC installs its own header files in
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another directory which is based on the <samp><span class="option">--prefix</span></samp> value.)
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<p>Both the local-prefix include directory and the GCC-prefix include
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directory are part of GCC's “system include” directories. Although these
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two directories are not fixed, they need to be searched in the proper
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order for the correct processing of the include_next directive. The
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local-prefix include directory is searched before the GCC-prefix
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include directory. Another characteristic of system include directories
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is that pedantic warnings are turned off for headers in these directories.
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<p>Some autoconf macros add <samp><span class="option">-I </span><var>directory</var></samp> options to the
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compiler command line, to ensure that directories containing installed
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packages' headers are searched. When <var>directory</var> is one of GCC's
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system include directories, GCC will ignore the option so that system
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directories continue to be processed in the correct order. This
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may result in a search order different from what was specified but the
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directory will still be searched.
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<p>GCC automatically searches for ordinary libraries using
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<samp><span class="env">GCC_EXEC_PREFIX</span></samp>. Thus, when the same installation prefix is
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used for both GCC and packages, GCC will automatically search for
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both headers and libraries. This provides a configuration that is
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easy to use. GCC behaves in a manner similar to that when it is
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installed as a system compiler in <samp><span class="file">/usr</span></samp>.
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<p>Sites that need to install multiple versions of GCC may not want to
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|
use the above simple configuration. It is possible to use the
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<samp><span class="option">--program-prefix</span></samp>, <samp><span class="option">--program-suffix</span></samp> and
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<samp><span class="option">--program-transform-name</span></samp> options to install multiple versions
|
|
into a single directory, but it may be simpler to use different prefixes
|
|
and the <samp><span class="option">--with-local-prefix</span></samp> option to specify the location of the
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site-specific files for each version. It will then be necessary for
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users to specify explicitly the location of local site libraries
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|
(e.g., with <samp><span class="env">LIBRARY_PATH</span></samp>).
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<p>The same value can be used for both <samp><span class="option">--with-local-prefix</span></samp> and
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|
<samp><span class="option">--prefix</span></samp> provided it is not <samp><span class="file">/usr</span></samp>. This can be used
|
|
to avoid the default search of <samp><span class="file">/usr/local/include</span></samp>.
|
|
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|
<p><strong>Do not</strong> specify <samp><span class="file">/usr</span></samp> as the <samp><span class="option">--with-local-prefix</span></samp>!
|
|
The directory you use for <samp><span class="option">--with-local-prefix</span></samp> <strong>must not</strong>
|
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contain any of the system's standard header files. If it did contain
|
|
them, certain programs would be miscompiled (including GNU Emacs, on
|
|
certain targets), because this would override and nullify the header
|
|
file corrections made by the <samp><span class="command">fixincludes</span></samp> script.
|
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|
<p>Indications are that people who use this option use it based on mistaken
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|
ideas of what it is for. People use it as if it specified where to
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install part of GCC. Perhaps they make this assumption because
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installing GCC creates the directory.
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|
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|
<br><dt><code>--with-gcc-major-version-only</code><dd>Specifies that GCC should use only the major number rather than
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|
<var>major</var>.<var>minor</var>.<var>patchlevel</var> in filesystem paths.
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|
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|
<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
|
|
header files, rather than <samp><span class="file">/usr/include</span></samp>. This option is most useful
|
|
if you are creating a compiler that should be isolated from the system
|
|
as much as possible. It is most commonly used with the
|
|
<samp><span class="option">--with-sysroot</span></samp> option and will cause GCC to search
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<var>dirname</var> inside the system root specified by that option.
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|
<br><dt><code>--enable-shared[=</code><var>package</var><code>[,...]]</code><dd>Build shared versions of libraries, if shared libraries are supported on
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|
the target platform. Unlike GCC 2.95.x and earlier, shared libraries
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|
are enabled by default on all platforms that support shared libraries.
|
|
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|
<p>If a list of packages is given as an argument, build shared libraries
|
|
only for the listed packages. For other packages, only static libraries
|
|
will be built. Package names currently recognized in the GCC tree are
|
|
‘<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
|
|
‘<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>’,
|
|
‘<samp><span class="samp">ada</span></samp>’, ‘<samp><span class="samp">libada</span></samp>’, ‘<samp><span class="samp">libgo</span></samp>’, and ‘<samp><span class="samp">libobjc</span></samp>’.
|
|
Note ‘<samp><span class="samp">libiberty</span></samp>’ does not support shared libraries at all.
|
|
|
|
<p>Use <samp><span class="option">--disable-shared</span></samp> to build only static libraries. Note that
|
|
<samp><span class="option">--disable-shared</span></samp> does not accept a list of package names as
|
|
argument, only <samp><span class="option">--enable-shared</span></samp> does.
|
|
|
|
<p>Contrast with <samp><span class="option">--enable-host-shared</span></samp>, which affects <em>host</em>
|
|
code.
|
|
|
|
<br><dt><code>--enable-host-shared</code><dd>Specify that the <em>host</em> code should be built into position-independent
|
|
machine code (with -fPIC), allowing it to be used within shared libraries,
|
|
but yielding a slightly slower compiler.
|
|
|
|
<p>This option is required when building the libgccjit.so library.
|
|
|
|
<p>Contrast with <samp><span class="option">--enable-shared</span></samp>, which affects <em>target</em>
|
|
libraries.
|
|
|
|
<br><dt><code><a name="with_002dgnu_002das"></a>--with-gnu-as</code><dd>Specify that the compiler should assume that the
|
|
assembler it finds is the GNU assembler. However, this does not modify
|
|
the rules to find an assembler and will result in confusion if the
|
|
assembler found is not actually the GNU assembler. (Confusion may also
|
|
result if the compiler finds the GNU assembler but has not been
|
|
configured with <samp><span class="option">--with-gnu-as</span></samp>.) If you have more than one
|
|
assembler installed on your system, you may want to use this option in
|
|
connection with <samp><span class="option">--with-as=</span><var>pathname</var></samp> or
|
|
<samp><span class="option">--with-build-time-tools=</span><var>pathname</var></samp>.
|
|
|
|
<p>The following systems are the only ones where it makes a difference
|
|
whether you use the GNU assembler. On any other system,
|
|
<samp><span class="option">--with-gnu-as</span></samp> has no effect.
|
|
|
|
<ul>
|
|
<li>‘<samp><span class="samp">hppa1.0-</span><var>any</var><span class="samp">-</span><var>any</var></samp>’
|
|
<li>‘<samp><span class="samp">hppa1.1-</span><var>any</var><span class="samp">-</span><var>any</var></samp>’
|
|
<li>‘<samp><span class="samp">sparc-sun-solaris2.</span><var>any</var></samp>’
|
|
<li>‘<samp><span class="samp">sparc64-</span><var>any</var><span class="samp">-solaris2.</span><var>any</var></samp>’
|
|
</ul>
|
|
|
|
<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
|
|
<var>pathname</var>, rather than the one found by the standard rules to find
|
|
an assembler, which are:
|
|
<ul>
|
|
<li>Unless GCC is being built with a cross compiler, check the
|
|
<samp><var>libexec</var><span class="file">/gcc/</span><var>target</var><span class="file">/</span><var>version</var></samp> directory.
|
|
<var>libexec</var> defaults to <samp><var>exec-prefix</var><span class="file">/libexec</span></samp>;
|
|
<var>exec-prefix</var> defaults to <var>prefix</var>, which
|
|
defaults to <samp><span class="file">/usr/local</span></samp> unless overridden by the
|
|
<samp><span class="option">--prefix=</span><var>pathname</var></samp> switch described above. <var>target</var>
|
|
is the target system triple, such as ‘<samp><span class="samp">sparc-sun-solaris2.7</span></samp>’, and
|
|
<var>version</var> denotes the GCC version, such as 3.0.
|
|
|
|
<li>If the target system is the same that you are building on, check
|
|
operating system specific directories (e.g. <samp><span class="file">/usr/ccs/bin</span></samp> on
|
|
Sun Solaris 2).
|
|
|
|
<li>Check in the <samp><span class="env">PATH</span></samp> for a tool whose name is prefixed by the
|
|
target system triple.
|
|
|
|
<li>Check in the <samp><span class="env">PATH</span></samp> for a tool whose name is not prefixed by the
|
|
target system triple, if the host and target system triple are
|
|
the same (in other words, we use a host tool if it can be used for
|
|
the target as well).
|
|
</ul>
|
|
|
|
<p>You may want to use <samp><span class="option">--with-as</span></samp> if no assembler
|
|
is installed in the directories listed above, or if you have multiple
|
|
assemblers installed and want to choose one that is not found by the
|
|
above rules.
|
|
|
|
<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>
|
|
but for the linker.
|
|
|
|
<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>
|
|
but for the linker.
|
|
|
|
<br><dt><code>--with-stabs</code><dd>Specify that stabs debugging
|
|
information should be used instead of whatever format the host normally
|
|
uses. Normally GCC uses the same debug format as the host system.
|
|
|
|
<p>On MIPS based systems and on Alphas, you must specify whether you want
|
|
GCC to create the normal ECOFF debugging format, or to use BSD-style
|
|
stabs passed through the ECOFF symbol table. The normal ECOFF debug
|
|
format cannot fully handle languages other than C. BSD stabs format can
|
|
handle other languages, but it only works with the GNU debugger GDB.
|
|
|
|
<p>Normally, GCC uses the ECOFF debugging format by default; if you
|
|
prefer BSD stabs, specify <samp><span class="option">--with-stabs</span></samp> when you configure GCC.
|
|
|
|
<p>No matter which default you choose when you configure GCC, the user
|
|
can use the <samp><span class="option">-gcoff</span></samp> and <samp><span class="option">-gstabs+</span></samp> options to specify explicitly
|
|
the debug format for a particular compilation.
|
|
|
|
<p><samp><span class="option">--with-stabs</span></samp> is meaningful on the ISC system on the 386, also, if
|
|
<samp><span class="option">--with-gas</span></samp> is used. It selects use of stabs debugging
|
|
information embedded in COFF output. This kind of debugging information
|
|
supports C++ well; ordinary COFF debugging information does not.
|
|
|
|
<p><samp><span class="option">--with-stabs</span></samp> is also meaningful on 386 systems running SVR4. It
|
|
selects use of stabs debugging information embedded in ELF output. The
|
|
C++ compiler currently (2.6.0) does not support the DWARF debugging
|
|
information normally used on 386 SVR4 platforms; stabs provide a
|
|
workable alternative. This requires gas and gdb, as the normal SVR4
|
|
tools can not generate or interpret stabs.
|
|
|
|
<br><dt><code>--with-tls=</code><var>dialect</var><dd>Specify the default TLS dialect, for systems were there is a choice.
|
|
For ARM targets, possible values for <var>dialect</var> are <code>gnu</code> or
|
|
<code>gnu2</code>, which select between the original GNU dialect and the GNU TLS
|
|
descriptor-based dialect.
|
|
|
|
<br><dt><code>--enable-multiarch</code><dd>Specify whether to enable or disable multiarch support. The default is
|
|
to check for glibc start files in a multiarch location, and enable it
|
|
if the files are found. The auto detection is enabled for native builds,
|
|
and for cross builds configured with <samp><span class="option">--with-sysroot</span></samp>, and without
|
|
<samp><span class="option">--with-native-system-header-dir</span></samp>.
|
|
More documentation about multiarch can be found at
|
|
<a href="https://wiki.debian.org/Multiarch">https://wiki.debian.org/Multiarch</a>.
|
|
|
|
<br><dt><code>--enable-sjlj-exceptions</code><dd>Force use of the <code>setjmp</code>/<code>longjmp</code>-based scheme for exceptions.
|
|
‘<samp><span class="samp">configure</span></samp>’ ordinarily picks the correct value based on the platform.
|
|
Only use this option if you are sure you need a different setting.
|
|
|
|
<br><dt><code>--enable-vtable-verify</code><dd>Specify whether to enable or disable the vtable verification feature.
|
|
Enabling this feature causes libstdc++ to be built with its virtual calls
|
|
in verifiable mode. This means that, when linked with libvtv, every
|
|
virtual call in libstdc++ will verify the vtable pointer through which the
|
|
call will be made before actually making the call. If not linked with libvtv,
|
|
the verifier will call stub functions (in libstdc++ itself) and do nothing.
|
|
If vtable verification is disabled, then libstdc++ is not built with its
|
|
virtual calls in verifiable mode at all. However the libvtv library will
|
|
still be built (see <samp><span class="option">--disable-libvtv</span></samp> to turn off building libvtv).
|
|
<samp><span class="option">--disable-vtable-verify</span></samp> is the default.
|
|
|
|
<br><dt><code>--disable-multilib</code><dd>Specify that multiple target
|
|
libraries to support different target variants, calling
|
|
conventions, etc. should not be built. The default is to build a
|
|
predefined set of them.
|
|
|
|
<p>Some targets provide finer-grained control over which multilibs are built
|
|
(e.g., <samp><span class="option">--disable-softfloat</span></samp>):
|
|
<dl>
|
|
<dt><code>arm-*-*</code><dd>fpu, 26bit, underscore, interwork, biendian, nofmult.
|
|
|
|
<br><dt><code>m68*-*-*</code><dd>softfloat, m68881, m68000, m68020.
|
|
|
|
<br><dt><code>mips*-*-*</code><dd>single-float, biendian, softfloat.
|
|
|
|
<br><dt><code>powerpc*-*-*, rs6000*-*-*</code><dd>aix64, pthread, softfloat, powercpu, powerpccpu, powerpcos, biendian,
|
|
sysv, aix.
|
|
|
|
</dl>
|
|
|
|
<br><dt><code>--with-multilib-list=</code><var>list</var><dt><code>--without-multilib-list</code><dd>Specify what multilibs to build. <var>list</var> is a comma separated list of
|
|
values, possibly consisting of a single value. Currently only implemented
|
|
for arm*-*-*, sh*-*-* and x86-64-*-linux*. The accepted values and meaning
|
|
for each target is given below.
|
|
|
|
<dl>
|
|
<dt><code>arm*-*-*</code><dd><var>list</var> is one of<code>default</code>, <code>aprofile</code> or <code>rmprofile</code>.
|
|
Specifying <code>default</code> is equivalent to omitting this option, ie. only the
|
|
default runtime library will be enabled. Specifying <code>aprofile</code> or
|
|
<code>rmprofile</code> builds multilibs for a combination of ISA, architecture,
|
|
FPU available and floating-point ABI.
|
|
|
|
<p>The table below gives the combination of ISAs, architectures, FPUs and
|
|
floating-point ABIs for which multilibs are built for each accepted value.
|
|
|
|
<p><table summary=""><tr align="left"><td valign="top" width="15%">Option </td><td valign="top" width="28%">aprofile </td><td valign="top" width="30%">rmprofile
|
|
<br></td></tr><tr align="left"><td valign="top" width="15%">ISAs
|
|
</td><td valign="top" width="28%"><code>-marm</code> and <code>-mthumb</code>
|
|
</td><td valign="top" width="30%"><code>-mthumb</code>
|
|
<br></td></tr><tr align="left"><td valign="top" width="15%">Architectures<br><br><br><br><br><br>
|
|
</td><td valign="top" width="28%">default architecture<br>
|
|
<code>-march=armv7-a</code><br>
|
|
<code>-march=armv7ve</code><br>
|
|
<code>-march=armv8-a</code><br><br><br>
|
|
</td><td valign="top" width="30%">default architecture<br>
|
|
<code>-march=armv6s-m</code><br>
|
|
<code>-march=armv7-m</code><br>
|
|
<code>-march=armv7e-m</code><br>
|
|
<code>-march=armv8-m.base</code><br>
|
|
<code>-march=armv8-m.main</code><br>
|
|
<code>-march=armv7</code>
|
|
<br></td></tr><tr align="left"><td valign="top" width="15%">FPUs<br><br><br><br><br>
|
|
</td><td valign="top" width="28%">none<br>
|
|
<code>-mfpu=vfpv3-d16</code><br>
|
|
<code>-mfpu=neon</code><br>
|
|
<code>-mfpu=vfpv4-d16</code><br>
|
|
<code>-mfpu=neon-vfpv4</code><br>
|
|
<code>-mfpu=neon-fp-armv8</code>
|
|
</td><td valign="top" width="30%">none<br>
|
|
<code>-mfpu=vfpv3-d16</code><br>
|
|
<code>-mfpu=fpv4-sp-d16</code><br>
|
|
<code>-mfpu=fpv5-sp-d16</code><br>
|
|
<code>-mfpu=fpv5-d16</code><br>
|
|
<br></td></tr><tr align="left"><td valign="top" width="15%">floating-point ABIs<br><br>
|
|
</td><td valign="top" width="28%"><code>-mfloat-abi=soft</code><br>
|
|
<code>-mfloat-abi=softfp</code><br>
|
|
<code>-mfloat-abi=hard</code>
|
|
</td><td valign="top" width="30%"><code>-mfloat-abi=soft</code><br>
|
|
<code>-mfloat-abi=softfp</code><br>
|
|
<code>-mfloat-abi=hard</code>
|
|
<br></td></tr></table>
|
|
|
|
<br><dt><code>sh*-*-*</code><dd><var>list</var> is a comma separated list of CPU names. These must be of the
|
|
form <code>sh*</code> or <code>m*</code> (in which case they match the compiler option
|
|
for that processor). The list should not contain any endian options -
|
|
these are handled by <samp><span class="option">--with-endian</span></samp>.
|
|
|
|
<p>If <var>list</var> is empty, then there will be no multilibs for extra
|
|
processors. The multilib for the secondary endian remains enabled.
|
|
|
|
<p>As a special case, if an entry in the list starts with a <code>!</code>
|
|
(exclamation point), then it is added to the list of excluded multilibs.
|
|
Entries of this sort should be compatible with ‘<samp><span class="samp">MULTILIB_EXCLUDES</span></samp>’
|
|
(once the leading <code>!</code> has been stripped).
|
|
|
|
<p>If <samp><span class="option">--with-multilib-list</span></samp> is not given, then a default set of
|
|
multilibs is selected based on the value of <samp><span class="option">--target</span></samp>. This is
|
|
usually the complete set of libraries, but some targets imply a more
|
|
specialized subset.
|
|
|
|
<p>Example 1: to configure a compiler for SH4A only, but supporting both
|
|
endians, with little endian being the default:
|
|
<pre class="smallexample"> --with-cpu=sh4a --with-endian=little,big --with-multilib-list=
|
|
</pre>
|
|
<p>Example 2: to configure a compiler for both SH4A and SH4AL-DSP, but with
|
|
only little endian SH4AL:
|
|
<pre class="smallexample"> --with-cpu=sh4a --with-endian=little,big \
|
|
--with-multilib-list=sh4al,!mb/m4al
|
|
</pre>
|
|
<br><dt><code>x86-64-*-linux*</code><dd><var>list</var> is a comma separated list of <code>m32</code>, <code>m64</code> and
|
|
<code>mx32</code> to enable 32-bit, 64-bit and x32 run-time libraries,
|
|
respectively. If <var>list</var> is empty, then there will be no multilibs
|
|
and only the default run-time library will be enabled.
|
|
|
|
<p>If <samp><span class="option">--with-multilib-list</span></samp> is not given, then only 32-bit and
|
|
64-bit run-time libraries will be enabled.
|
|
</dl>
|
|
|
|
<br><dt><code>--with-endian=</code><var>endians</var><dd>Specify what endians to use.
|
|
Currently only implemented for sh*-*-*.
|
|
|
|
<p><var>endians</var> may be one of the following:
|
|
<dl>
|
|
<dt><code>big</code><dd>Use big endian exclusively.
|
|
<br><dt><code>little</code><dd>Use little endian exclusively.
|
|
<br><dt><code>big,little</code><dd>Use big endian by default. Provide a multilib for little endian.
|
|
<br><dt><code>little,big</code><dd>Use little endian by default. Provide a multilib for big endian.
|
|
</dl>
|
|
|
|
<br><dt><code>--enable-threads</code><dd>Specify that the target
|
|
supports threads. This affects the Objective-C compiler and runtime
|
|
library, and exception handling for other languages like C++.
|
|
On some systems, this is the default.
|
|
|
|
<p>In general, the best (and, in many cases, the only known) threading
|
|
model available will be configured for use. Beware that on some
|
|
systems, GCC has not been taught what threading models are generally
|
|
available for the system. In this case, <samp><span class="option">--enable-threads</span></samp> is an
|
|
alias for <samp><span class="option">--enable-threads=single</span></samp>.
|
|
|
|
<br><dt><code>--disable-threads</code><dd>Specify that threading support should be disabled for the system.
|
|
This is an alias for <samp><span class="option">--enable-threads=single</span></samp>.
|
|
|
|
<br><dt><code>--enable-threads=</code><var>lib</var><dd>Specify that
|
|
<var>lib</var> is the thread support library. This affects the Objective-C
|
|
compiler and runtime library, and exception handling for other languages
|
|
like C++. The possibilities for <var>lib</var> are:
|
|
|
|
<dl>
|
|
<dt><code>aix</code><dd>AIX thread support.
|
|
<br><dt><code>dce</code><dd>DCE thread support.
|
|
<br><dt><code>lynx</code><dd>LynxOS thread support.
|
|
<br><dt><code>mipssde</code><dd>MIPS SDE thread support.
|
|
<br><dt><code>no</code><dd>This is an alias for ‘<samp><span class="samp">single</span></samp>’.
|
|
<br><dt><code>posix</code><dd>Generic POSIX/Unix98 thread support.
|
|
<br><dt><code>rtems</code><dd>RTEMS thread support.
|
|
<br><dt><code>single</code><dd>Disable thread support, should work for all platforms.
|
|
<br><dt><code>tpf</code><dd>TPF thread support.
|
|
<br><dt><code>vxworks</code><dd>VxWorks thread support.
|
|
<br><dt><code>win32</code><dd>Microsoft Win32 API thread support.
|
|
</dl>
|
|
|
|
<br><dt><code>--enable-tls</code><dd>Specify that the target supports TLS (Thread Local Storage). Usually
|
|
configure can correctly determine if TLS is supported. In cases where
|
|
it guesses incorrectly, TLS can be explicitly enabled or disabled with
|
|
<samp><span class="option">--enable-tls</span></samp> or <samp><span class="option">--disable-tls</span></samp>. This can happen if
|
|
the assembler supports TLS but the C library does not, or if the
|
|
assumptions made by the configure test are incorrect.
|
|
|
|
<br><dt><code>--disable-tls</code><dd>Specify that the target does not support TLS.
|
|
This is an alias for <samp><span class="option">--enable-tls=no</span></samp>.
|
|
|
|
<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.
|
|
<var>cpu</var> will be used as the default value of the <samp><span class="option">-mcpu=</span></samp> switch.
|
|
This option is only supported on some targets, including ARC, ARM, i386, M68k,
|
|
PowerPC, and SPARC. It is mandatory for ARC. The <samp><span class="option">--with-cpu-32</span></samp> and
|
|
<samp><span class="option">--with-cpu-64</span></samp> options specify separate default CPUs for
|
|
32-bit and 64-bit modes; these options are only supported for i386,
|
|
x86-64, PowerPC, and SPARC.
|
|
|
|
<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>,
|
|
<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>
|
|
options and for <samp><span class="option">-mhard-float</span></samp> or <samp><span class="option">-msoft-float</span></samp>. As with
|
|
<samp><span class="option">--with-cpu</span></samp>, which switches will be accepted and acceptable values
|
|
of the arguments depend on the target.
|
|
|
|
<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>.
|
|
This option is only supported on ARM targets.
|
|
|
|
<br><dt><code>--with-stack-offset=</code><var>num</var><dd>This option sets the default for the -mstack-offset=<var>num</var> option,
|
|
and will thus generally also control the setting of this option for
|
|
libraries. This option is only supported on Epiphany targets.
|
|
|
|
<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
|
|
ISA for floating-point arithmetics. You can select either ‘<samp><span class="samp">sse</span></samp>’ which
|
|
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.
|
|
This option is only supported on i386 and x86-64 targets.
|
|
|
|
<br><dt><code>--with-fp-32=</code><var>mode</var><dd>On MIPS targets, set the default value for the <samp><span class="option">-mfp</span></samp> option when using
|
|
the o32 ABI. The possibilities for <var>mode</var> are:
|
|
<dl>
|
|
<dt><code>32</code><dd>Use the o32 FP32 ABI extension, as with the <samp><span class="option">-mfp32</span></samp> command-line
|
|
option.
|
|
<br><dt><code>xx</code><dd>Use the o32 FPXX ABI extension, as with the <samp><span class="option">-mfpxx</span></samp> command-line
|
|
option.
|
|
<br><dt><code>64</code><dd>Use the o32 FP64 ABI extension, as with the <samp><span class="option">-mfp64</span></samp> command-line
|
|
option.
|
|
</dl>
|
|
In the absence of this configuration option the default is to use the o32
|
|
FP32 ABI extension.
|
|
|
|
<br><dt><code>--with-odd-spreg-32</code><dd>On MIPS targets, set the <samp><span class="option">-modd-spreg</span></samp> option by default when using
|
|
the o32 ABI.
|
|
|
|
<br><dt><code>--without-odd-spreg-32</code><dd>On MIPS targets, set the <samp><span class="option">-mno-odd-spreg</span></samp> option by default when using
|
|
the o32 ABI. This is normally used in conjunction with
|
|
<samp><span class="option">--with-fp-32=64</span></samp> in order to target the o32 FP64A ABI extension.
|
|
|
|
<br><dt><code>--with-nan=</code><var>encoding</var><dd>On MIPS targets, set the default encoding convention to use for the
|
|
special not-a-number (NaN) IEEE 754 floating-point data. The
|
|
possibilities for <var>encoding</var> are:
|
|
<dl>
|
|
<dt><code>legacy</code><dd>Use the legacy encoding, as with the <samp><span class="option">-mnan=legacy</span></samp> command-line
|
|
option.
|
|
<br><dt><code>2008</code><dd>Use the 754-2008 encoding, as with the <samp><span class="option">-mnan=2008</span></samp> command-line
|
|
option.
|
|
</dl>
|
|
To use this configuration option you must have an assembler version
|
|
installed that supports the <samp><span class="option">-mnan=</span></samp> command-line option too.
|
|
In the absence of this configuration option the default convention is
|
|
the legacy encoding, as when neither of the <samp><span class="option">-mnan=2008</span></samp> and
|
|
<samp><span class="option">-mnan=legacy</span></samp> command-line options has been used.
|
|
|
|
<br><dt><code>--with-divide=</code><var>type</var><dd>Specify how the compiler should generate code for checking for
|
|
division by zero. This option is only supported on the MIPS target.
|
|
The possibilities for <var>type</var> are:
|
|
<dl>
|
|
<dt><code>traps</code><dd>Division by zero checks use conditional traps (this is the default on
|
|
systems that support conditional traps).
|
|
<br><dt><code>breaks</code><dd>Division by zero checks use the break instruction.
|
|
</dl>
|
|
|
|
<!-- If you make -with-llsc the default for additional targets, -->
|
|
<!-- update the -with-llsc description in the MIPS section below. -->
|
|
<br><dt><code>--with-llsc</code><dd>On MIPS targets, make <samp><span class="option">-mllsc</span></samp> the default when no
|
|
<samp><span class="option">-mno-llsc</span></samp> option is passed. This is the default for
|
|
Linux-based targets, as the kernel will emulate them if the ISA does
|
|
not provide them.
|
|
|
|
<br><dt><code>--without-llsc</code><dd>On MIPS targets, make <samp><span class="option">-mno-llsc</span></samp> the default when no
|
|
<samp><span class="option">-mllsc</span></samp> option is passed.
|
|
|
|
<br><dt><code>--with-synci</code><dd>On MIPS targets, make <samp><span class="option">-msynci</span></samp> the default when no
|
|
<samp><span class="option">-mno-synci</span></samp> option is passed.
|
|
|
|
<br><dt><code>--without-synci</code><dd>On MIPS targets, make <samp><span class="option">-mno-synci</span></samp> the default when no
|
|
<samp><span class="option">-msynci</span></samp> option is passed. This is the default.
|
|
|
|
<br><dt><code>--with-lxc1-sxc1</code><dd>On MIPS targets, make <samp><span class="option">-mlxc1-sxc1</span></samp> the default when no
|
|
<samp><span class="option">-mno-lxc1-sxc1</span></samp> option is passed. This is the default.
|
|
|
|
<br><dt><code>--without-lxc1-sxc1</code><dd>On MIPS targets, make <samp><span class="option">-mno-lxc1-sxc1</span></samp> the default when no
|
|
<samp><span class="option">-mlxc1-sxc1</span></samp> option is passed. The indexed load/store
|
|
instructions are not directly a problem but can lead to unexpected
|
|
behaviour when deployed in an application intended for a 32-bit address
|
|
space but run on a 64-bit processor. The issue is seen because all
|
|
known MIPS 64-bit Linux kernels execute o32 and n32 applications
|
|
with 64-bit addressing enabled which affects the overflow behaviour
|
|
of the indexed addressing mode. GCC will assume that ordinary
|
|
32-bit arithmetic overflow behaviour is the same whether performed
|
|
as an <code>addu</code> instruction or as part of the address calculation
|
|
in <code>lwxc1</code> type instructions. This assumption holds true in a
|
|
pure 32-bit environment and can hold true in a 64-bit environment if
|
|
the address space is accurately set to be 32-bit for o32 and n32.
|
|
|
|
<br><dt><code>--with-madd4</code><dd>On MIPS targets, make <samp><span class="option">-mmadd4</span></samp> the default when no
|
|
<samp><span class="option">-mno-madd4</span></samp> option is passed. This is the default.
|
|
|
|
<br><dt><code>--without-madd4</code><dd>On MIPS targets, make <samp><span class="option">-mno-madd4</span></samp> the default when no
|
|
<samp><span class="option">-mmadd4</span></samp> option is passed. The <code>madd4</code> instruction
|
|
family can be problematic when targeting a combination of cores that
|
|
implement these instructions differently. There are two known cores
|
|
that implement these as fused operations instead of unfused (where
|
|
unfused is normally expected). Disabling these instructions is the
|
|
only way to ensure compatible code is generated; this will incur
|
|
a performance penalty.
|
|
|
|
<br><dt><code>--with-mips-plt</code><dd>On MIPS targets, make use of copy relocations and PLTs.
|
|
These features are extensions to the traditional
|
|
SVR4-based MIPS ABIs and require support from GNU binutils
|
|
and the runtime C library.
|
|
|
|
<br><dt><code>--enable-__cxa_atexit</code><dd>Define if you want to use __cxa_atexit, rather than atexit, to
|
|
register C++ destructors for local statics and global objects.
|
|
This is essential for fully standards-compliant handling of
|
|
destructors, but requires __cxa_atexit in libc. This option is currently
|
|
only available on systems with GNU libc. When enabled, this will cause
|
|
<samp><span class="option">-fuse-cxa-atexit</span></samp> to be passed by default.
|
|
|
|
<br><dt><code>--enable-gnu-indirect-function</code><dd>Define if you want to enable the <code>ifunc</code> attribute. This option is
|
|
currently only available on systems with GNU libc on certain targets.
|
|
|
|
<br><dt><code>--enable-target-optspace</code><dd>Specify that target
|
|
libraries should be optimized for code space instead of code speed.
|
|
This is the default for the m32r platform.
|
|
|
|
<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
|
|
in <samp><var>prefix</var><span class="file">/</span><var>dirname</var><span class="file">/cpp</span></samp>, in addition to <var>bindir</var>.
|
|
|
|
<br><dt><code>--enable-comdat</code><dd>Enable COMDAT group support. This is primarily used to override the
|
|
automatically detected value.
|
|
|
|
<br><dt><code>--enable-initfini-array</code><dd>Force the use of sections <code>.init_array</code> and <code>.fini_array</code>
|
|
(instead of <code>.init</code> and <code>.fini</code>) for constructors and
|
|
destructors. Option <samp><span class="option">--disable-initfini-array</span></samp> has the
|
|
opposite effect. If neither option is specified, the configure script
|
|
will try to guess whether the <code>.init_array</code> and
|
|
<code>.fini_array</code> sections are supported and, if they are, use them.
|
|
|
|
<br><dt><code>--enable-link-mutex</code><dd>When building GCC, use a mutex to avoid linking the compilers for
|
|
multiple languages at the same time, to avoid thrashing on build
|
|
systems with limited free memory. The default is not to use such a mutex.
|
|
|
|
<br><dt><code>--enable-maintainer-mode</code><dd>The build rules that regenerate the Autoconf and Automake output files as
|
|
well as the GCC master message catalog <samp><span class="file">gcc.pot</span></samp> are normally
|
|
disabled. This is because it can only be rebuilt if the complete source
|
|
tree is present. If you have changed the sources and want to rebuild the
|
|
catalog, configuring with <samp><span class="option">--enable-maintainer-mode</span></samp> will enable
|
|
this. Note that you need a recent version of the <code>gettext</code> tools
|
|
to do so.
|
|
|
|
<br><dt><code>--disable-bootstrap</code><dd>For a native build, the default configuration is to perform
|
|
a 3-stage bootstrap of the compiler when ‘<samp><span class="samp">make</span></samp>’ is invoked,
|
|
testing that GCC can compile itself correctly. If you want to disable
|
|
this process, you can configure with <samp><span class="option">--disable-bootstrap</span></samp>.
|
|
|
|
<br><dt><code>--enable-bootstrap</code><dd>In special cases, you may want to perform a 3-stage build
|
|
even if the target and host triplets are different.
|
|
This is possible when the host can run code compiled for
|
|
the target (e.g. host is i686-linux, target is i486-linux).
|
|
Starting from GCC 4.2, to do this you have to configure explicitly
|
|
with <samp><span class="option">--enable-bootstrap</span></samp>.
|
|
|
|
<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
|
|
info manuals and man pages that are built from the .texi files are present
|
|
in the SVN development tree. When building GCC from that development tree,
|
|
or from one of our snapshots, those generated files are placed in your
|
|
build directory, which allows for the source to be in a readonly
|
|
directory.
|
|
|
|
<p>If you configure with <samp><span class="option">--enable-generated-files-in-srcdir</span></samp> then those
|
|
generated files will go into the source directory. This is mainly intended
|
|
for generating release or prerelease tarballs of the GCC sources, since it
|
|
is not a requirement that the users of source releases to have flex, Bison,
|
|
or makeinfo.
|
|
|
|
<br><dt><code>--enable-version-specific-runtime-libs</code><dd>Specify
|
|
that runtime libraries should be installed in the compiler specific
|
|
subdirectory (<samp><var>libdir</var><span class="file">/gcc</span></samp>) rather than the usual places. In
|
|
addition, ‘<samp><span class="samp">libstdc++</span></samp>’'s include files will be installed into
|
|
<samp><var>libdir</var></samp> unless you overruled it by using
|
|
<samp><span class="option">--with-gxx-include-dir=</span><var>dirname</var></samp>. Using this option is
|
|
particularly useful if you intend to use several versions of GCC in
|
|
parallel. This is currently supported by ‘<samp><span class="samp">libgfortran</span></samp>’,
|
|
‘<samp><span class="samp">libstdc++</span></samp>’, and ‘<samp><span class="samp">libobjc</span></samp>’.
|
|
|
|
<br><dt><code><a name="WithAixSoname"></a>--with-aix-soname=‘</code><samp><span class="samp">aix</span></samp><code>’, ‘</code><samp><span class="samp">svr4</span></samp><code>’ or ‘</code><samp><span class="samp">both</span></samp><code>’</code><dd>Traditional AIX shared library versioning (versioned <code>Shared Object</code>
|
|
files as members of unversioned <code>Archive Library</code> files named
|
|
‘<samp><span class="samp">lib.a</span></samp>’) causes numerous headaches for package managers. However,
|
|
<code>Import Files</code> as members of <code>Archive Library</code> files allow for
|
|
<strong>filename-based versioning</strong> of shared libraries as seen on Linux/SVR4,
|
|
where this is called the "SONAME". But as they prevent static linking,
|
|
<code>Import Files</code> may be used with <code>Runtime Linking</code> only, where the
|
|
linker does search for ‘<samp><span class="samp">libNAME.so</span></samp>’ before ‘<samp><span class="samp">libNAME.a</span></samp>’ library
|
|
filenames with the ‘<samp><span class="samp">-lNAME</span></samp>’ linker flag.
|
|
|
|
<p><a name="AixLdCommand"></a>For detailed information please refer to the AIX
|
|
<a href="https://www.ibm.com/support/knowledgecenter/search/%22the%20ld%20command%2C%20also%20called%20the%20linkage%20editor%20or%20binder%22">ld Command</a> reference.
|
|
|
|
<p>As long as shared library creation is enabled, upon:
|
|
<dl>
|
|
<dt><code>--with-aix-soname=aix</code><br><dt><code>--with-aix-soname=both</code><dd> A (traditional AIX) <code>Shared Archive Library</code> file is created:
|
|
<ul>
|
|
<li>using the ‘<samp><span class="samp">libNAME.a</span></samp>’ filename scheme
|
|
<li>with the <code>Shared Object</code> file as archive member named
|
|
‘<samp><span class="samp">libNAME.so.V</span></samp>’ (except for ‘<samp><span class="samp">libgcc_s</span></samp>’, where the <code>Shared
|
|
Object</code> file is named ‘<samp><span class="samp">shr.o</span></samp>’ for backwards compatibility), which
|
|
<ul>
|
|
<li>is used for runtime loading from inside the ‘<samp><span class="samp">libNAME.a</span></samp>’ file
|
|
<li>is used for dynamic loading via
|
|
<code>dlopen("libNAME.a(libNAME.so.V)", RTLD_MEMBER)</code>
|
|
<li>is used for shared linking
|
|
<li>is used for static linking, so no separate <code>Static Archive
|
|
Library</code> file is needed
|
|
</ul>
|
|
</ul>
|
|
<br><dt><code>--with-aix-soname=both</code><br><dt><code>--with-aix-soname=svr4</code><dd> A (second) <code>Shared Archive Library</code> file is created:
|
|
<ul>
|
|
<li>using the ‘<samp><span class="samp">libNAME.so.V</span></samp>’ filename scheme
|
|
<li>with the <code>Shared Object</code> file as archive member named
|
|
‘<samp><span class="samp">shr.o</span></samp>’, which
|
|
<ul>
|
|
<li>is created with the <code>-G linker flag</code>
|
|
<li>has the <code>F_LOADONLY</code> flag set
|
|
<li>is used for runtime loading from inside the ‘<samp><span class="samp">libNAME.so.V</span></samp>’ file
|
|
<li>is used for dynamic loading via <code>dlopen("libNAME.so.V(shr.o)",
|
|
RTLD_MEMBER)</code>
|
|
</ul>
|
|
<li>with the <code>Import File</code> as archive member named ‘<samp><span class="samp">shr.imp</span></samp>’,
|
|
which
|
|
<ul>
|
|
<li>refers to ‘<samp><span class="samp">libNAME.so.V(shr.o)</span></samp>’ as the "SONAME", to be recorded
|
|
in the <code>Loader Section</code> of subsequent binaries
|
|
<li>indicates whether ‘<samp><span class="samp">libNAME.so.V(shr.o)</span></samp>’ is 32 or 64 bit
|
|
<li>lists all the public symbols exported by ‘<samp><span class="samp">lib.so.V(shr.o)</span></samp>’,
|
|
eventually decorated with the <code>‘</code><samp><span class="samp">weak</span></samp><code>’ Keyword</code>
|
|
<li>is necessary for shared linking against ‘<samp><span class="samp">lib.so.V(shr.o)</span></samp>’
|
|
</ul>
|
|
</ul>
|
|
A symbolic link using the ‘<samp><span class="samp">libNAME.so</span></samp>’ filename scheme is created:
|
|
<ul>
|
|
<li>pointing to the ‘<samp><span class="samp">libNAME.so.V</span></samp>’ <code>Shared Archive Library</code> file
|
|
<li>to permit the <code>ld Command</code> to find ‘<samp><span class="samp">lib.so.V(shr.imp)</span></samp>’ via
|
|
the ‘<samp><span class="samp">-lNAME</span></samp>’ argument (requires <code>Runtime Linking</code> to be enabled)
|
|
<li>to permit dynamic loading of ‘<samp><span class="samp">lib.so.V(shr.o)</span></samp>’ without the need
|
|
to specify the version number via <code>dlopen("libNAME.so(shr.o)",
|
|
RTLD_MEMBER)</code>
|
|
</ul>
|
|
</dl>
|
|
|
|
<p>As long as static library creation is enabled, upon:
|
|
<dl>
|
|
<dt><code>--with-aix-soname=svr4</code><dd> A <code>Static Archive Library</code> is created:
|
|
<ul>
|
|
<li>using the ‘<samp><span class="samp">libNAME.a</span></samp>’ filename scheme
|
|
<li>with all the <code>Static Object</code> files as archive members, which
|
|
<ul>
|
|
<li>are used for static linking
|
|
</ul>
|
|
</ul>
|
|
</dl>
|
|
|
|
<p>While the aix-soname=‘<samp><span class="samp">svr4</span></samp>’ option does not create <code>Shared Object</code>
|
|
files as members of unversioned <code>Archive Library</code> files any more, package
|
|
managers still are responsible to
|
|
<a href="./specific.html#TransferAixShobj">transfer</a> <code>Shared Object</code> files
|
|
found as member of a previously installed unversioned <code>Archive Library</code>
|
|
file into the newly installed <code>Archive Library</code> file with the same
|
|
filename.
|
|
|
|
<p><em>WARNING:</em> Creating <code>Shared Object</code> files with <code>Runtime Linking</code>
|
|
enabled may bloat the TOC, eventually leading to <code>TOC overflow</code> errors,
|
|
requiring the use of either the <samp><span class="option">-Wl,-bbigtoc</span></samp> linker flag (seen to
|
|
break with the <code>GDB</code> debugger) or some of the TOC-related compiler flags,
|
|
see “RS/6000 and PowerPC Options” in the main manual.
|
|
|
|
<p><samp><span class="option">--with-aix-soname</span></samp> is currently supported by ‘<samp><span class="samp">libgcc_s</span></samp>’ only, so
|
|
this option is still experimental and not for normal use yet.
|
|
|
|
<p>Default is the traditional behavior <samp><span class="option">--with-aix-soname=‘</span><samp><span class="samp">aix</span></samp><span class="option">’</span></samp>.
|
|
|
|
<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
|
|
their runtime libraries should be built. For a list of valid values for
|
|
<var>langN</var> you can issue the following command in the
|
|
<samp><span class="file">gcc</span></samp> directory of your GCC source tree:<br>
|
|
<pre class="smallexample"> grep ^language= */config-lang.in
|
|
</pre>
|
|
<p>Currently, you can use any of the following:
|
|
<code>all</code>, <code>ada</code>, <code>c</code>, <code>c++</code>, <code>fortran</code>,
|
|
<code>go</code>, <code>jit</code>, <code>lto</code>, <code>objc</code>, <code>obj-c++</code>.
|
|
Building the Ada compiler has special requirements, see below.
|
|
If you do not pass this flag, or specify the option <code>all</code>, then all
|
|
default languages available in the <samp><span class="file">gcc</span></samp> sub-tree will be configured.
|
|
Ada, Go, Jit, and Objective-C++ are not default languages. LTO is not a
|
|
default language, but is built by default because <samp><span class="option">--enable-lto</span></samp> is
|
|
enabled by default. The other languages are default languages.
|
|
|
|
<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
|
|
libraries should be built with the system C compiler during stage 1 of
|
|
the bootstrap process, rather than only in later stages with the
|
|
bootstrapped C compiler. The list of valid values is the same as for
|
|
<samp><span class="option">--enable-languages</span></samp>, and the option <code>all</code> will select all
|
|
of the languages enabled by <samp><span class="option">--enable-languages</span></samp>. This option is
|
|
primarily useful for GCC development; for instance, when a development
|
|
version of the compiler cannot bootstrap due to compiler bugs, or when
|
|
one is debugging front ends other than the C front end. When this
|
|
option is used, one can then build the target libraries for the
|
|
specified languages with the stage-1 compiler by using <samp><span class="command">make
|
|
stage1-bubble all-target</span></samp>, or run the testsuite on the stage-1 compiler
|
|
for the specified languages using <samp><span class="command">make stage1-start check-gcc</span></samp>.
|
|
|
|
<br><dt><code>--disable-libada</code><dd>Specify that the run-time libraries and tools used by GNAT should not
|
|
be built. This can be useful for debugging, or for compatibility with
|
|
previous Ada build procedures, when it was required to explicitly
|
|
do a ‘<samp><span class="samp">make -C gcc gnatlib_and_tools</span></samp>’.
|
|
|
|
<br><dt><code>--disable-libsanitizer</code><dd>Specify that the run-time libraries for the various sanitizers should
|
|
not be built.
|
|
|
|
<br><dt><code>--disable-libssp</code><dd>Specify that the run-time libraries for stack smashing protection
|
|
should not be built.
|
|
|
|
<br><dt><code>--disable-libquadmath</code><dd>Specify that the GCC quad-precision math library should not be built.
|
|
On some systems, the library is required to be linkable when building
|
|
the Fortran front end, unless <samp><span class="option">--disable-libquadmath-support</span></samp>
|
|
is used.
|
|
|
|
<br><dt><code>--disable-libquadmath-support</code><dd>Specify that the Fortran front end and <code>libgfortran</code> do not add
|
|
support for <code>libquadmath</code> on systems supporting it.
|
|
|
|
<br><dt><code>--disable-libgomp</code><dd>Specify that the GNU Offloading and Multi Processing Runtime Library
|
|
should not be built.
|
|
|
|
<br><dt><code>--disable-libvtv</code><dd>Specify that the run-time libraries used by vtable verification
|
|
should not be built.
|
|
|
|
<br><dt><code>--with-dwarf2</code><dd>Specify that the compiler should
|
|
use DWARF 2 debugging information as the default.
|
|
|
|
<br><dt><code>--with-advance-toolchain=</code><var>at</var><dd>On 64-bit PowerPC Linux systems, configure the compiler to use the
|
|
header files, library files, and the dynamic linker from the Advance
|
|
Toolchain release <var>at</var> instead of the default versions that are
|
|
provided by the Linux distribution. In general, this option is
|
|
intended for the developers of GCC, and it is not intended for general
|
|
use.
|
|
|
|
<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.
|
|
These are compilers that are able to generate either 64-bit or 32-bit
|
|
code. Typically, the corresponding 32-bit target, e.g.
|
|
powerpc-linux for powerpc64-linux, only generates 32-bit code. This
|
|
option enables the 32-bit target to be a bi-arch compiler, which is
|
|
useful when you want a bi-arch compiler that defaults to 32-bit, and
|
|
you are building a bi-arch or multi-arch binutils in a combined tree.
|
|
On mips-linux, this will build a tri-arch compiler (ABI o32/n32/64),
|
|
defaulted to o32.
|
|
Currently, this option only affects sparc-linux, powerpc-linux, x86-linux,
|
|
mips-linux and s390-linux.
|
|
|
|
<br><dt><code>--enable-default-pie</code><dd>Turn on <samp><span class="option">-fPIE</span></samp> and <samp><span class="option">-pie</span></samp> by default.
|
|
|
|
<br><dt><code>--enable-secureplt</code><dd>This option enables <samp><span class="option">-msecure-plt</span></samp> by default for powerpc-linux.
|
|
See “RS/6000 and PowerPC Options” in the main manual
|
|
|
|
<br><dt><code>--enable-default-ssp</code><dd>Turn on <samp><span class="option">-fstack-protector-strong</span></samp> by default.
|
|
|
|
<br><dt><code>--enable-cld</code><dd>This option enables <samp><span class="option">-mcld</span></samp> by default for 32-bit x86 targets.
|
|
See “i386 and x86-64 Options” in the main manual
|
|
|
|
<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
|
|
to look up installations paths in the registry using the following key:
|
|
|
|
<pre class="smallexample"> <code>HKEY_LOCAL_MACHINE\SOFTWARE\Free Software Foundation\</code><var>key</var>
|
|
</pre>
|
|
<p><var>key</var> defaults to GCC version number, and can be overridden by the
|
|
<samp><span class="option">--enable-win32-registry=</span><var>key</var></samp> option. Vendors and distributors
|
|
who use custom installers are encouraged to provide a different key,
|
|
perhaps one comprised of vendor name and GCC version number, to
|
|
avoid conflict with existing installations. This feature is enabled
|
|
by default, and can be disabled by <samp><span class="option">--disable-win32-registry</span></samp>
|
|
option. This option has no effect on the other hosts.
|
|
|
|
<br><dt><code>--nfp</code><dd>Specify that the machine does not have a floating point unit. This
|
|
option only applies to ‘<samp><span class="samp">m68k-sun-sunos</span><var>n</var></samp>’. On any other
|
|
system, <samp><span class="option">--nfp</span></samp> has no effect.
|
|
|
|
<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
|
|
compiler are built with <samp><span class="option">-Werror</span></samp> in bootstrap stage2 and later.
|
|
If you don't specify it, <samp><span class="option">-Werror</span></samp> is turned on for the main
|
|
development trunk. However it defaults to off for release branches and
|
|
final releases. The specific files which get <samp><span class="option">-Werror</span></samp> are
|
|
controlled by the Makefiles.
|
|
|
|
<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
|
|
consistency checks of the requested complexity. This does not change the
|
|
generated code, but adds error checking within the compiler. This will
|
|
slow down the compiler and may only work properly if you are building
|
|
the compiler with GCC. This is ‘<samp><span class="samp">yes,extra</span></samp>’ by default when building
|
|
from SVN or snapshots, but ‘<samp><span class="samp">release</span></samp>’ for releases. The default
|
|
for building the stage1 compiler is ‘<samp><span class="samp">yes</span></samp>’. More control
|
|
over the checks may be had by specifying <var>list</var>. The categories of
|
|
checks available are ‘<samp><span class="samp">yes</span></samp>’ (most common checks
|
|
‘<samp><span class="samp">assert,misc,tree,gc,rtlflag,runtime</span></samp>’), ‘<samp><span class="samp">no</span></samp>’ (no checks at
|
|
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
|
|
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>’).
|
|
Individual checks can be enabled with these flags ‘<samp><span class="samp">assert</span></samp>’,
|
|
‘<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>’,
|
|
‘<samp><span class="samp">rtlflag</span></samp>’, ‘<samp><span class="samp">runtime</span></samp>’, ‘<samp><span class="samp">tree</span></samp>’, ‘<samp><span class="samp">extra</span></samp>’ and ‘<samp><span class="samp">valgrind</span></samp>’.
|
|
‘<samp><span class="samp">extra</span></samp>’ adds for ‘<samp><span class="samp">misc</span></samp>’ checking extra checks that might affect
|
|
code generation and should therefore not differ between stage1 and later
|
|
stages.
|
|
|
|
<p>The ‘<samp><span class="samp">valgrind</span></samp>’ check requires the external <samp><span class="command">valgrind</span></samp>
|
|
simulator, available from <a href="http://valgrind.org/">http://valgrind.org/</a>. The
|
|
‘<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.
|
|
To disable all checking, ‘<samp><span class="samp">--disable-checking</span></samp>’ or
|
|
‘<samp><span class="samp">--enable-checking=none</span></samp>’ must be explicitly requested. Disabling
|
|
assertions will make the compiler and runtime slightly faster but
|
|
increase the risk of undetected internal errors causing wrong code to be
|
|
generated.
|
|
|
|
<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
|
|
compiler will be built with ‘<samp><span class="samp">yes</span></samp>’ checking enabled, otherwise
|
|
the stage1 checking flags are the same as specified by
|
|
<samp><span class="option">--enable-checking</span></samp>. To build the stage1 compiler with
|
|
different checking options use <samp><span class="option">--enable-stage1-checking</span></samp>.
|
|
The list of checking options is the same as for <samp><span class="option">--enable-checking</span></samp>.
|
|
If your system is too slow or too small to bootstrap a released compiler
|
|
with checking for stage1 enabled, you can use ‘<samp><span class="samp">--disable-stage1-checking</span></samp>’
|
|
to disable checking for the stage1 compiler.
|
|
|
|
<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
|
|
information, every time it is run. This is for internal development
|
|
purposes, and only works when the compiler is being built with gcc. The
|
|
<var>level</var> argument controls whether the compiler is built optimized or
|
|
not, values are ‘<samp><span class="samp">opt</span></samp>’ and ‘<samp><span class="samp">noopt</span></samp>’. For coverage analysis you
|
|
want to disable optimization, for performance analysis you want to
|
|
enable optimization. When coverage is enabled, the default level is
|
|
without optimization.
|
|
|
|
<br><dt><code>--enable-gather-detailed-mem-stats</code><dd>When this option is specified more detailed information on memory
|
|
allocation is gathered. This information is printed when using
|
|
<samp><span class="option">-fmem-report</span></samp>.
|
|
|
|
<br><dt><code>--enable-valgrind-annotations</code><dd>Mark selected memory related operations in the compiler when run under
|
|
valgrind to suppress false positives.
|
|
|
|
<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),
|
|
which lets GCC output diagnostics in languages other than American
|
|
English. Native Language Support is enabled by default if not doing a
|
|
canadian cross build. The <samp><span class="option">--disable-nls</span></samp> option disables NLS.
|
|
|
|
<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
|
|
procedure to prefer its copy of GNU <samp><span class="command">gettext</span></samp>.
|
|
|
|
<br><dt><code>--with-catgets</code><dd>If NLS is enabled, and if the host lacks <code>gettext</code> but has the
|
|
inferior <code>catgets</code> interface, the GCC build procedure normally
|
|
ignores <code>catgets</code> and instead uses GCC's copy of the GNU
|
|
<code>gettext</code> library. The <samp><span class="option">--with-catgets</span></samp> option causes the
|
|
build procedure to use the host's <code>catgets</code> in this situation.
|
|
|
|
<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
|
|
libiconv library files in <samp><var>dir</var><span class="file">/lib</span></samp>.
|
|
|
|
<br><dt><code>--enable-obsolete</code><dd>Enable configuration for an obsoleted system. If you attempt to
|
|
configure GCC for a system (build, host, or target) which has been
|
|
obsoleted, and you do not specify this flag, configure will halt with an
|
|
error message.
|
|
|
|
<p>All support for systems which have been obsoleted in one release of GCC
|
|
is removed entirely in the next major release, unless someone steps
|
|
forward to maintain the port.
|
|
|
|
<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
|
|
that is in the IEEE 754-2008 standard. This is enabled by default only
|
|
on PowerPC, i386, and x86_64 GNU/Linux systems. Other systems may also
|
|
support it, but require the user to specifically enable it. You can
|
|
optionally control which decimal floating point format is used (either
|
|
‘<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)
|
|
format is default on i386 and x86_64 systems, and the ‘<samp><span class="samp">dpd</span></samp>’
|
|
(densely packed decimal) format is default on PowerPC systems.
|
|
|
|
<br><dt><code>--enable-fixed-point</code><dt><code>--disable-fixed-point</code><dd>Enable (or disable) support for C fixed-point arithmetic.
|
|
This option is enabled by default for some targets (such as MIPS) which
|
|
have hardware-support for fixed-point operations. On other targets, you
|
|
may enable this option manually.
|
|
|
|
<br><dt><code>--with-long-double-128</code><dd>Specify if <code>long double</code> type should be 128-bit by default on selected
|
|
GNU/Linux architectures. If using <code>--without-long-double-128</code>,
|
|
<code>long double</code> will be by default 64-bit, the same as <code>double</code> type.
|
|
When neither of these configure options are used, the default will be
|
|
128-bit <code>long double</code> when built against GNU C Library 2.4 and later,
|
|
64-bit <code>long double</code> otherwise.
|
|
|
|
<br><dt><code>--enable-fdpic</code><dd>On SH Linux systems, generate ELF FDPIC code.
|
|
|
|
<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
|
|
library and/or the MPC library installed in a standard location and
|
|
do not have their sources present in the GCC source tree then you
|
|
can explicitly specify the directory where they are installed
|
|
(‘<samp><span class="samp">--with-gmp=</span><var>gmpinstalldir</var></samp>’,
|
|
‘<samp><span class="samp">--with-mpfr=</span><var>mpfrinstalldir</var></samp>’,
|
|
‘<samp><span class="samp">--with-mpc=</span><var>mpcinstalldir</var></samp>’). The
|
|
<samp><span class="option">--with-gmp=</span><var>gmpinstalldir</var></samp> option is shorthand for
|
|
<samp><span class="option">--with-gmp-lib=</span><var>gmpinstalldir</var><span class="option">/lib</span></samp> and
|
|
<samp><span class="option">--with-gmp-include=</span><var>gmpinstalldir</var><span class="option">/include</span></samp>. Likewise the
|
|
<samp><span class="option">--with-mpfr=</span><var>mpfrinstalldir</var></samp> option is shorthand for
|
|
<samp><span class="option">--with-mpfr-lib=</span><var>mpfrinstalldir</var><span class="option">/lib</span></samp> and
|
|
<samp><span class="option">--with-mpfr-include=</span><var>mpfrinstalldir</var><span class="option">/include</span></samp>, also the
|
|
<samp><span class="option">--with-mpc=</span><var>mpcinstalldir</var></samp> option is shorthand for
|
|
<samp><span class="option">--with-mpc-lib=</span><var>mpcinstalldir</var><span class="option">/lib</span></samp> and
|
|
<samp><span class="option">--with-mpc-include=</span><var>mpcinstalldir</var><span class="option">/include</span></samp>. If these
|
|
shorthand assumptions are not correct, you can use the explicit
|
|
include and lib options directly. You might also need to ensure the
|
|
shared libraries can be found by the dynamic linker when building and
|
|
using GCC, for example by setting the runtime shared library path
|
|
variable (<samp><span class="env">LD_LIBRARY_PATH</span></samp> on GNU/Linux and Solaris systems).
|
|
|
|
<p>These flags are applicable to the host platform only. When building
|
|
a cross compiler, they will not be used to configure target libraries.
|
|
|
|
<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><dd>If you do not have the isl library installed in a standard location and you
|
|
want to build GCC, you can explicitly specify the directory where it is
|
|
installed (‘<samp><span class="samp">--with-isl=</span><var>islinstalldir</var></samp>’). The
|
|
<samp><span class="option">--with-isl=</span><var>islinstalldir</var></samp> option is shorthand for
|
|
<samp><span class="option">--with-isl-lib=</span><var>islinstalldir</var><span class="option">/lib</span></samp> and
|
|
<samp><span class="option">--with-isl-include=</span><var>islinstalldir</var><span class="option">/include</span></samp>. If this
|
|
shorthand assumption is not correct, you can use the explicit
|
|
include and lib options directly.
|
|
|
|
<p>These flags are applicable to the host platform only. When building
|
|
a cross compiler, they will not be used to configure target libraries.
|
|
|
|
<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
|
|
stage 1 of GCC. These are also used when linking GCC if configured with
|
|
<samp><span class="option">--disable-bootstrap</span></samp>. If <samp><span class="option">--with-stage1-libs</span></samp> is not set to a
|
|
value, then the default is ‘<samp><span class="samp">-static-libstdc++ -static-libgcc</span></samp>’, if
|
|
supported.
|
|
|
|
<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
|
|
of GCC. These are also used when linking GCC if configured with
|
|
<samp><span class="option">--disable-bootstrap</span></samp>.
|
|
|
|
<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
|
|
stage 2 and later when bootstrapping GCC. If –with-boot-libs
|
|
is not is set to a value, then the default is
|
|
‘<samp><span class="samp">-static-libstdc++ -static-libgcc</span></samp>’.
|
|
|
|
<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
|
|
and later when bootstrapping GCC.
|
|
|
|
<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
|
|
building runtime libraries. ‘<samp><var>map</var></samp>’ is a space-separated
|
|
list of maps of the form ‘<samp><var>old</var><span class="samp">=</span><var>new</var></samp>’.
|
|
|
|
<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
|
|
links (links performed without the <samp><span class="option">-r</span></samp> or <samp><span class="option">--relocatable</span></samp>
|
|
option), if the linker supports it. If you specify
|
|
<samp><span class="option">--enable-linker-build-id</span></samp>, but your linker does not
|
|
support <samp><span class="option">--build-id</span></samp> option, a warning is issued and the
|
|
<samp><span class="option">--enable-linker-build-id</span></samp> option is ignored. The default is off.
|
|
|
|
<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
|
|
linker for all final links. <var>choice</var> can be one of
|
|
‘<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.
|
|
|
|
<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
|
|
static data members and inline function local statics. Enabled by
|
|
default for a toolchain with an assembler that accepts it and
|
|
GLIBC 2.11 or above, otherwise disabled.
|
|
|
|
<br><dt><code>--with-diagnostics-color=</code><var>choice</var><dd>Tells GCC to use <var>choice</var> as the default for <samp><span class="option">-fdiagnostics-color=</span></samp>
|
|
option (if not used explicitly on the command line). <var>choice</var>
|
|
can be one of ‘<samp><span class="samp">never</span></samp>’, ‘<samp><span class="samp">auto</span></samp>’, ‘<samp><span class="samp">always</span></samp>’, and ‘<samp><span class="samp">auto-if-env</span></samp>’
|
|
where ‘<samp><span class="samp">auto</span></samp>’ is the default. ‘<samp><span class="samp">auto-if-env</span></samp>’ means that
|
|
<samp><span class="option">-fdiagnostics-color=auto</span></samp> will be the default if <code>GCC_COLORS</code>
|
|
is present and non-empty in the environment, and
|
|
<samp><span class="option">-fdiagnostics-color=never</span></samp> otherwise.
|
|
|
|
<br><dt><code>--enable-lto</code><dt><code>--disable-lto</code><dd>Enable support for link-time optimization (LTO). This is enabled by
|
|
default, and may be disabled using <samp><span class="option">--disable-lto</span></samp>.
|
|
|
|
<br><dt><code>--enable-linker-plugin-configure-flags=FLAGS</code><dt><code>--enable-linker-plugin-flags=FLAGS</code><dd>By default, linker plugins (such as the LTO plugin) are built for the
|
|
host system architecture. For the case that the linker has a
|
|
different (but run-time compatible) architecture, these flags can be
|
|
specified to build plugins that are compatible to the linker. For
|
|
example, if you are building GCC for a 64-bit x86_64
|
|
(‘<samp><span class="samp">x86_64-unknown-linux-gnu</span></samp>’) host system, but have a 32-bit x86
|
|
GNU/Linux (‘<samp><span class="samp">i686-pc-linux-gnu</span></samp>’) linker executable (which is
|
|
executable on the former system), you can configure GCC as follows for
|
|
getting compatible linker plugins:
|
|
|
|
<pre class="smallexample"> % <var>srcdir</var>/configure \
|
|
--host=x86_64-unknown-linux-gnu \
|
|
--enable-linker-plugin-configure-flags=--host=i686-pc-linux-gnu \
|
|
--enable-linker-plugin-flags='CC=gcc\ -m32\ -Wl,-rpath,[...]/i686-pc-linux-gnu/lib'
|
|
</pre>
|
|
<br><dt><code>--with-plugin-ld=</code><var>pathname</var><dd>Enable an alternate linker to be used at link-time optimization (LTO)
|
|
link time when <samp><span class="option">-fuse-linker-plugin</span></samp> is enabled.
|
|
This linker should have plugin support such as gold starting with
|
|
version 2.20 or GNU ld starting with version 2.21.
|
|
See <samp><span class="option">-fuse-linker-plugin</span></samp> for details.
|
|
|
|
<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
|
|
produce shorter header file paths in diagnostics and dependency output
|
|
files, but these changed header paths may conflict with some compilation
|
|
environments. Enabled by default, and may be disabled using
|
|
<samp><span class="option">--disable-canonical-system-headers</span></samp>.
|
|
|
|
<br><dt><code>--with-glibc-version=</code><var>major</var><code>.</code><var>minor</var><dd>Tell GCC that when the GNU C Library (glibc) is used on the target it
|
|
will be version <var>major</var>.<var>minor</var> or later. Normally this can
|
|
be detected from the C library's header files, but this option may be
|
|
needed when bootstrapping a cross toolchain without the header files
|
|
available for building the initial bootstrap compiler.
|
|
|
|
<p>If GCC is configured with some multilibs that use glibc and some that
|
|
do not, this option applies only to the multilibs that use glibc.
|
|
However, such configurations may not work well as not all the relevant
|
|
configuration in GCC is on a per-multilib basis.
|
|
|
|
<br><dt><code>--enable-as-accelerator-for=</code><var>target</var><dd>Build as offload target compiler. Specify offload host triple by <var>target</var>.
|
|
|
|
<br><dt><code>--enable-offload-targets=</code><var>target1</var><code>[=</code><var>path1</var><code>],...,</code><var>targetN</var><code>[=</code><var>pathN</var><code>]</code><dd>Enable offloading to targets <var>target1</var>, <small class="dots">...</small>, <var>targetN</var>.
|
|
Offload compilers are expected to be already installed. Default search
|
|
path for them is <samp><var>exec-prefix</var></samp>, but it can be changed by
|
|
specifying paths <var>path1</var>, <small class="dots">...</small>, <var>pathN</var>.
|
|
|
|
<pre class="smallexample"> % <var>srcdir</var>/configure \
|
|
--enable-offload-target=i686-unknown-linux-gnu=/path/to/i686/compiler,x86_64-pc-linux-gnu
|
|
</pre>
|
|
<p>If ‘<samp><span class="samp">hsa</span></samp>’ is specified as one of the targets, the compiler will be
|
|
built with support for HSA GPU accelerators. Because the same
|
|
compiler will emit the accelerator code, no path should be specified.
|
|
|
|
<br><dt><code>--with-hsa-runtime=</code><var>pathname</var><dt><code>--with-hsa-runtime-include=</code><var>pathname</var><dt><code>--with-hsa-runtime-lib=</code><var>pathname</var><dd>
|
|
If you configure GCC with HSA offloading but do not have the HSA
|
|
run-time library installed in a standard location then you can
|
|
explicitly specify the directory where they are installed. The
|
|
<samp><span class="option">--with-hsa-runtime=</span><var>hsainstalldir</var></samp> option is a
|
|
shorthand for
|
|
<samp><span class="option">--with-hsa-runtime-lib=</span><var>hsainstalldir</var><span class="option">/lib</span></samp> and
|
|
<samp><span class="option">--with-hsa-runtime-include=</span><var>hsainstalldir</var><span class="option">/include</span></samp>.
|
|
</dl>
|
|
|
|
<h4 class="subheading"><a name="TOC3"></a>Cross-Compiler-Specific Options</h4>
|
|
|
|
<p>The following options only apply to building cross compilers.
|
|
|
|
<dl>
|
|
<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
|
|
(a subset of) the root filesystem of the target operating system.
|
|
Target system headers, libraries and run-time object files will be
|
|
searched for in there. More specifically, this acts as if
|
|
<samp><span class="option">--sysroot=</span><var>dir</var></samp> was added to the default options of the built
|
|
compiler. The specified directory is not copied into the
|
|
install tree, unlike the options <samp><span class="option">--with-headers</span></samp> and
|
|
<samp><span class="option">--with-libs</span></samp> that this option obsoletes. The default value,
|
|
in case <samp><span class="option">--with-sysroot</span></samp> is not given an argument, is
|
|
<samp><span class="option">${gcc_tooldir}/sys-root</span></samp>. If the specified directory is a
|
|
subdirectory of <samp><span class="option">${exec_prefix}</span></samp>, then it will be found relative to
|
|
the GCC binaries if the installation tree is moved.
|
|
|
|
<p>This option affects the system root for the compiler used to build
|
|
target libraries (which runs on the build system) and the compiler newly
|
|
installed with <code>make install</code>; it does not affect the compiler which is
|
|
used to build GCC itself.
|
|
|
|
<p>If you specify the <samp><span class="option">--with-native-system-header-dir=</span><var>dirname</var></samp>
|
|
option then the compiler will search that directory within <var>dirname</var> for
|
|
native system headers rather than the default <samp><span class="file">/usr/include</span></samp>.
|
|
|
|
<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
|
|
<samp><span class="option">--with-sysroot</span></samp>) while building target libraries, instead of
|
|
the directory specified with <samp><span class="option">--with-sysroot</span></samp>. This option is
|
|
only useful when you are already using <samp><span class="option">--with-sysroot</span></samp>. You
|
|
can use <samp><span class="option">--with-build-sysroot</span></samp> when you are configuring with
|
|
<samp><span class="option">--prefix</span></samp> set to a directory that is different from the one in
|
|
which you are installing GCC and your target libraries.
|
|
|
|
<p>This option affects the system root for the compiler used to build
|
|
target libraries (which runs on the build system); it does not affect
|
|
the compiler which is used to build GCC itself.
|
|
|
|
<p>If you specify the <samp><span class="option">--with-native-system-header-dir=</span><var>dirname</var></samp>
|
|
option then the compiler will search that directory within <var>dirname</var> for
|
|
native system headers rather than the default <samp><span class="file">/usr/include</span></samp>.
|
|
|
|
<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>.
|
|
Specifies that target headers are available when building a cross compiler.
|
|
The <var>dir</var> argument specifies a directory which has the target include
|
|
files. These include files will be copied into the <samp><span class="file">gcc</span></samp> install
|
|
directory. <em>This option with the </em><var>dir</var><em> argument is required</em> when
|
|
building a cross compiler, if <samp><var>prefix</var><span class="file">/</span><var>target</var><span class="file">/sys-include</span></samp>
|
|
doesn't pre-exist. If <samp><var>prefix</var><span class="file">/</span><var>target</var><span class="file">/sys-include</span></samp> does
|
|
pre-exist, the <var>dir</var> argument may be omitted. <samp><span class="command">fixincludes</span></samp>
|
|
will be run on these files to make them compatible with GCC.
|
|
|
|
<br><dt><code>--without-headers</code><dd>Tells GCC not use any target headers from a libc when building a cross
|
|
compiler. When crossing to GNU/Linux, you need the headers so GCC
|
|
can build the exception handling for libgcc.
|
|
|
|
<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>.
|
|
Specifies a list of directories which contain the target runtime
|
|
libraries. These libraries will be copied into the <samp><span class="file">gcc</span></samp> install
|
|
directory. If the directory list is omitted, this option has no
|
|
effect.
|
|
|
|
<br><dt><code>--with-newlib</code><dd>Specifies that ‘<samp><span class="samp">newlib</span></samp>’ is
|
|
being used as the target C library. This causes <code>__eprintf</code> to be
|
|
omitted from <samp><span class="file">libgcc.a</span></samp> on the assumption that it will be provided by
|
|
‘<samp><span class="samp">newlib</span></samp>’.
|
|
|
|
<br><dt><code>--with-avrlibc</code><dd>Specifies that ‘<samp><span class="samp">AVR-Libc</span></samp>’ is
|
|
being used as the target C library. This causes float support
|
|
functions like <code>__addsf3</code> to be omitted from <samp><span class="file">libgcc.a</span></samp> on
|
|
the assumption that it will be provided by <samp><span class="file">libm.a</span></samp>. For more
|
|
technical details, cf. <a href="http://gcc.gnu.org/PR54461">PR54461</a>.
|
|
This option is only supported for the AVR target. It is not supported for
|
|
RTEMS configurations, which currently use newlib. The option is
|
|
supported since version 4.7.2 and is the default in 4.8.0 and newer.
|
|
|
|
<br><dt><code>--with-nds32-lib=</code><var>library</var><dd>Specifies that <var>library</var> setting is used for building <samp><span class="file">libgcc.a</span></samp>.
|
|
Currently, the valid <var>library</var> is ‘<samp><span class="samp">newlib</span></samp>’ or ‘<samp><span class="samp">mculib</span></samp>’.
|
|
This option is only supported for the NDS32 target.
|
|
|
|
<br><dt><code>--with-build-time-tools=</code><var>dir</var><dd>Specifies where to find the set of target tools (assembler, linker, etc.)
|
|
that will be used while building GCC itself. This option can be useful
|
|
if the directory layouts are different between the system you are building
|
|
GCC on, and the system where you will deploy it.
|
|
|
|
<p>For example, on an ‘<samp><span class="samp">ia64-hp-hpux</span></samp>’ system, you may have the GNU
|
|
assembler and linker in <samp><span class="file">/usr/bin</span></samp>, and the native tools in a
|
|
different path, and build a toolchain that expects to find the
|
|
native tools in <samp><span class="file">/usr/bin</span></samp>.
|
|
|
|
<p>When you use this option, you should ensure that <var>dir</var> includes
|
|
<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>,
|
|
<samp><span class="command">ranlib</span></samp> and <samp><span class="command">strip</span></samp> if necessary, and possibly
|
|
<samp><span class="command">objdump</span></samp>. Otherwise, GCC may use an inconsistent set of
|
|
tools.
|
|
</dl>
|
|
|
|
<h5 class="subsubheading"><a name="TOC4"></a>Overriding <samp><span class="command">configure</span></samp> test results</h5>
|
|
|
|
<p>Sometimes, it might be necessary to override the result of some
|
|
<samp><span class="command">configure</span></samp> test, for example in order to ease porting to a new
|
|
system or work around a bug in a test. The toplevel <samp><span class="command">configure</span></samp>
|
|
script provides three variables for this:
|
|
|
|
<dl>
|
|
<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>
|
|
scripts.
|
|
|
|
<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>
|
|
scripts.
|
|
|
|
<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>
|
|
scripts.
|
|
|
|
</dl>
|
|
|
|
<p>In order to avoid shell and <samp><span class="command">make</span></samp> quoting issues for complex
|
|
overrides, you can pass a setting for <samp><span class="env">CONFIG_SITE</span></samp> and set
|
|
variables in the site file.
|
|
|
|
<h4 class="subheading"><a name="TOC5"></a>Objective-C-Specific Options</h4>
|
|
|
|
<p>The following options apply to the build of the Objective-C runtime library.
|
|
|
|
<dl>
|
|
<dt><code>--enable-objc-gc</code><dd>Specify that an additional variant of the GNU Objective-C runtime library
|
|
is built, using an external build of the Boehm-Demers-Weiser garbage
|
|
collector (<a href="http://www.hboehm.info/gc/">http://www.hboehm.info/gc/</a>). This library needs to be
|
|
available for each multilib variant, unless configured with
|
|
<samp><span class="option">--enable-objc-gc=‘</span><samp><span class="samp">auto</span></samp><span class="option">’</span></samp> in which case the build of the
|
|
additional runtime library is skipped when not available and the build
|
|
continues.
|
|
|
|
<br><dt><code>--with-target-bdw-gc=</code><var>list</var><dt><code>--with-target-bdw-gc-include=</code><var>list</var><dt><code>--with-target-bdw-gc-lib=</code><var>list</var><dd>Specify search directories for the garbage collector header files and
|
|
libraries. <var>list</var> is a comma separated list of key value pairs of the
|
|
form ‘<samp><var>multilibdir</var><span class="samp">=</span><var>path</var></samp>’, where the default multilib key
|
|
is named as ‘<samp><span class="samp">.</span></samp>’ (dot), or is omitted (e.g.
|
|
‘<samp><span class="samp">--with-target-bdw-gc=/opt/bdw-gc,32=/opt-bdw-gc32</span></samp>’).
|
|
|
|
<p>The options <samp><span class="option">--with-target-bdw-gc-include</span></samp> and
|
|
<samp><span class="option">--with-target-bdw-gc-lib</span></samp> must always be specified together
|
|
for each multilib variant and they take precedence over
|
|
<samp><span class="option">--with-target-bdw-gc</span></samp>. If <samp><span class="option">--with-target-bdw-gc-include</span></samp>
|
|
is missing values for a multilib, then the value for the default
|
|
multilib is used (e.g. ‘<samp><span class="samp">--with-target-bdw-gc-include=/opt/bdw-gc/include</span></samp>’
|
|
‘<samp><span class="samp">--with-target-bdw-gc-lib=/opt/bdw-gc/lib64,32=/opt-bdw-gc/lib32</span></samp>’).
|
|
If none of these options are specified, the library is assumed in
|
|
default locations.
|
|
</dl>
|
|
|
|
<p><hr />
|
|
<p><a href="./index.html">Return to the GCC Installation page</a>
|
|
|
|
<!-- ***Building**************************************************************** -->
|
|
<!-- ***Testing***************************************************************** -->
|
|
<!-- ***Final install*********************************************************** -->
|
|
<!-- ***Binaries**************************************************************** -->
|
|
<!-- ***Specific**************************************************************** -->
|
|
<!-- ***Old documentation****************************************************** -->
|
|
<!-- ***GFDL******************************************************************** -->
|
|
<!-- *************************************************************************** -->
|
|
<!-- Part 6 The End of the Document -->
|
|
</body></html>
|
|
|