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1<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd"> 2<html> 3<!-- Copyright (C) 1988-2015 Free Software Foundation, Inc. 4 5Permission is granted to copy, distribute and/or modify this document 6under the terms of the GNU Free Documentation License, Version 1.3 or 7any later version published by the Free Software Foundation; with no 8Invariant Sections, the Front-Cover texts being (a) (see below), and 9with the Back-Cover Texts being (b) (see below). A copy of the 10license is included in the section entitled "GNU 11Free Documentation License". 12 13(a) The FSF's Front-Cover Text is: 14 15A GNU Manual 16 17(b) The FSF's Back-Cover Text is: 18 19You have freedom to copy and modify this GNU Manual, like GNU 20 software. Copies published by the Free Software Foundation raise 21 funds for GNU development. --> 22<!-- Created by GNU Texinfo 6.1, http://www.gnu.org/software/texinfo/ --> 23<head> 24<title>Installing GCC</title> 25 26<meta name="description" content="Installing GCC"> 27<meta name="keywords" content="Installing GCC"> 28<meta name="resource-type" content="document"> 29<meta name="distribution" content="global"> 30<meta name="Generator" content="makeinfo"> 31<meta http-equiv="Content-Type" content="text/html; charset=utf-8"> 32<style type="text/css"> 33<!-- 34a.summary-letter {text-decoration: none} 35blockquote.indentedblock {margin-right: 0em} 36blockquote.smallindentedblock {margin-right: 0em; font-size: smaller} 37blockquote.smallquotation {font-size: smaller} 38div.display {margin-left: 3.2em} 39div.example {margin-left: 3.2em} 40div.lisp {margin-left: 3.2em} 41div.smalldisplay {margin-left: 3.2em} 42div.smallexample {margin-left: 3.2em} 43div.smalllisp {margin-left: 3.2em} 44kbd {font-style: oblique} 45pre.display {font-family: inherit} 46pre.format {font-family: inherit} 47pre.menu-comment {font-family: serif} 48pre.menu-preformatted {font-family: serif} 49pre.smalldisplay {font-family: inherit; font-size: smaller} 50pre.smallexample {font-size: smaller} 51pre.smallformat {font-family: inherit; font-size: smaller} 52pre.smalllisp {font-size: smaller} 53span.nolinebreak {white-space: nowrap} 54span.roman {font-family: initial; font-weight: normal} 55span.sansserif {font-family: sans-serif; font-weight: normal} 56ul.no-bullet {list-style: none} 57--> 58</style> 59 60 61</head> 62 63<body lang="en"> 64<h1 class="settitle" align="center">Installing GCC</h1> 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84<a name="index-Configuration"></a> 85<a name="index-Installing-GCC_003a-Configuration"></a> 86 87<p>Like most GNU software, GCC must be configured before it can be built. 88This document describes the recommended configuration procedure 89for both native and cross targets. 90</p> 91<p>We use <var>srcdir</var> to refer to the toplevel source directory for 92GCC; we use <var>objdir</var> to refer to the toplevel build/object directory. 93</p> 94<p>If you obtained the sources via SVN, <var>srcdir</var> must refer to the top 95<samp>gcc</samp> directory, the one where the <samp>MAINTAINERS</samp> file can be 96found, and not its <samp>gcc</samp> subdirectory, otherwise the build will fail. 97</p> 98<p>If either <var>srcdir</var> or <var>objdir</var> is located on an automounted NFS 99file system, the shell’s built-in <code>pwd</code> command will return 100temporary pathnames. Using these can lead to various sorts of build 101problems. To avoid this issue, set the <code>PWDCMD</code> environment 102variable to an automounter-aware <code>pwd</code> command, e.g., 103<code>pawd</code> or ‘<samp>amq -w</samp>’, during the configuration and build 104phases. 105</p> 106<p>First, we <strong>highly</strong> recommend that GCC be built into a 107separate directory from the sources which does <strong>not</strong> reside 108within the source tree. This is how we generally build GCC; building 109where <var>srcdir</var> == <var>objdir</var> should still work, but doesn’t 110get extensive testing; building where <var>objdir</var> is a subdirectory 111of <var>srcdir</var> is unsupported. 112</p> 113<p>If you have previously built GCC in the same directory for a 114different target machine, do ‘<samp>make distclean</samp>’ to delete all files 115that might be invalid. One of the files this deletes is <samp>Makefile</samp>; 116if ‘<samp>make distclean</samp>’ complains that <samp>Makefile</samp> does not exist 117or issues a message like “don’t know how to make distclean” it probably 118means that the directory is already suitably clean. However, with the 119recommended method of building in a separate <var>objdir</var>, you should 120simply use a different <var>objdir</var> for each target. 121</p> 122<p>Second, when configuring a native system, either <code>cc</code> or 123<code>gcc</code> must be in your path or you must set <code>CC</code> in 124your environment before running configure. Otherwise the configuration 125scripts may fail. 126</p> 127 128<p>To configure GCC: 129</p> 130<div class="smallexample"> 131<pre class="smallexample">% mkdir <var>objdir</var> 132% cd <var>objdir</var> 133% <var>srcdir</var>/configure [<var>options</var>] [<var>target</var>] 134</pre></div> 135 136<a name="Distributor-options"></a> 137<h3 class="heading">Distributor options</h3> 138 139<p>If you will be distributing binary versions of GCC, with modifications 140to the source code, you should use the options described in this 141section to make clear that your version contains modifications. 142</p> 143<dl compact="compact"> 144<dt><code>--with-pkgversion=<var>version</var></code></dt> 145<dd><p>Specify a string that identifies your package. You may wish 146to include a build number or build date. This version string will be 147included in the output of <code>gcc --version</code>. This suffix does 148not replace the default version string, only the ‘<samp>GCC</samp>’ part. 149</p> 150<p>The default value is ‘<samp>GCC</samp>’. 151</p> 152</dd> 153<dt><code>--with-bugurl=<var>url</var></code></dt> 154<dd><p>Specify the URL that users should visit if they wish to report a bug. 155You are of course welcome to forward bugs reported to you to the FSF, 156if you determine that they are not bugs in your modifications. 157</p> 158<p>The default value refers to the FSF’s GCC bug tracker. 159</p> 160</dd> 161</dl> 162 163<a name="Target-specification"></a> 164<h3 class="heading">Target specification</h3> 165<ul> 166<li> GCC has code to correctly determine the correct value for <var>target</var> 167for nearly all native systems. Therefore, we highly recommend you do 168not provide a configure target when configuring a native compiler. 169 170</li><li> <var>target</var> must be specified as <samp>--target=<var>target</var></samp> 171when configuring a cross compiler; examples of valid targets would be 172m68k-elf, sh-elf, etc. 173 174</li><li> Specifying just <var>target</var> instead of <samp>--target=<var>target</var></samp> 175implies that the host defaults to <var>target</var>. 176</li></ul> 177 178 179<a name="Options-specification"></a> 180<h3 class="heading">Options specification</h3> 181 182<p>Use <var>options</var> to override several configure time options for 183GCC. A list of supported <var>options</var> follows; ‘<samp>configure 184--help</samp>’ may list other options, but those not listed below may not 185work and should not normally be used. 186</p> 187<p>Note that each <samp>--enable</samp> option has a corresponding 188<samp>--disable</samp> option and that each <samp>--with</samp> option has a 189corresponding <samp>--without</samp> option. 190</p> 191<dl compact="compact"> 192<dt><code>--prefix=<var>dirname</var></code></dt> 193<dd><p>Specify the toplevel installation 194directory. This is the recommended way to install the tools into a directory 195other than the default. The toplevel installation directory defaults to 196<samp>/usr/local</samp>. 197</p> 198<p>We <strong>highly</strong> recommend against <var>dirname</var> being the same or a 199subdirectory of <var>objdir</var> or vice versa. If specifying a directory 200beneath a user’s home directory tree, some shells will not expand 201<var>dirname</var> correctly if it contains the ‘<samp>~</samp>’ metacharacter; use 202<code>$HOME</code> instead. 203</p> 204<p>The following standard <code>autoconf</code> options are supported. Normally you 205should not need to use these options. 206</p><dl compact="compact"> 207<dt><code>--exec-prefix=<var>dirname</var></code></dt> 208<dd><p>Specify the toplevel installation directory for architecture-dependent 209files. The default is <samp><var>prefix</var></samp>. 210</p> 211</dd> 212<dt><code>--bindir=<var>dirname</var></code></dt> 213<dd><p>Specify the installation directory for the executables called by users 214(such as <code>gcc</code> and <code>g++</code>). The default is 215<samp><var>exec-prefix</var>/bin</samp>. 216</p> 217</dd> 218<dt><code>--libdir=<var>dirname</var></code></dt> 219<dd><p>Specify the installation directory for object code libraries and 220internal data files of GCC. The default is <samp><var>exec-prefix</var>/lib</samp>. 221</p> 222</dd> 223<dt><code>--libexecdir=<var>dirname</var></code></dt> 224<dd><p>Specify the installation directory for internal executables of GCC. 225The default is <samp><var>exec-prefix</var>/libexec</samp>. 226</p> 227</dd> 228<dt><code>--with-slibdir=<var>dirname</var></code></dt> 229<dd><p>Specify the installation directory for the shared libgcc library. The 230default is <samp><var>libdir</var></samp>. 231</p> 232</dd> 233<dt><code>--datarootdir=<var>dirname</var></code></dt> 234<dd><p>Specify the root of the directory tree for read-only architecture-independent 235data files referenced by GCC. The default is <samp><var>prefix</var>/share</samp>. 236</p> 237</dd> 238<dt><code>--infodir=<var>dirname</var></code></dt> 239<dd><p>Specify the installation directory for documentation in info format. 240The default is <samp><var>datarootdir</var>/info</samp>. 241</p> 242</dd> 243<dt><code>--datadir=<var>dirname</var></code></dt> 244<dd><p>Specify the installation directory for some architecture-independent 245data files referenced by GCC. The default is <samp><var>datarootdir</var></samp>. 246</p> 247</dd> 248<dt><code>--docdir=<var>dirname</var></code></dt> 249<dd><p>Specify the installation directory for documentation files (other 250than Info) for GCC. The default is <samp><var>datarootdir</var>/doc</samp>. 251</p> 252</dd> 253<dt><code>--htmldir=<var>dirname</var></code></dt> 254<dd><p>Specify the installation directory for HTML documentation files. 255The default is <samp><var>docdir</var></samp>. 256</p> 257</dd> 258<dt><code>--pdfdir=<var>dirname</var></code></dt> 259<dd><p>Specify the installation directory for PDF documentation files. 260The default is <samp><var>docdir</var></samp>. 261</p> 262</dd> 263<dt><code>--mandir=<var>dirname</var></code></dt> 264<dd><p>Specify the installation directory for manual pages. The default is 265<samp><var>datarootdir</var>/man</samp>. (Note that the manual pages are only extracts 266from the full GCC manuals, which are provided in Texinfo format. The manpages 267are derived by an automatic conversion process from parts of the full 268manual.) 269</p> 270</dd> 271<dt><code>--with-gxx-include-dir=<var>dirname</var></code></dt> 272<dd><p>Specify 273the installation directory for G++ header files. The default depends 274on other configuration options, and differs between cross and native 275configurations. 276</p> 277</dd> 278<dt><code>--with-specs=<var>specs</var></code></dt> 279<dd><p>Specify additional command line driver SPECS. 280This can be useful if you need to turn on a non-standard feature by 281default without modifying the compiler’s source code, for instance 282<samp>--with-specs=%{!fcommon:%{!fno-common:-fno-common}}</samp>. 283See “Spec Files” in the main manual 284</p> 285</dd> 286</dl> 287 288</dd> 289<dt><code>--program-prefix=<var>prefix</var></code></dt> 290<dd><p>GCC supports some transformations of the names of its programs when 291installing them. This option prepends <var>prefix</var> to the names of 292programs to install in <var>bindir</var> (see above). For example, specifying 293<samp>--program-prefix=foo-</samp> would result in ‘<samp>gcc</samp>’ 294being installed as <samp>/usr/local/bin/foo-gcc</samp>. 295</p> 296</dd> 297<dt><code>--program-suffix=<var>suffix</var></code></dt> 298<dd><p>Appends <var>suffix</var> to the names of programs to install in <var>bindir</var> 299(see above). For example, specifying <samp>--program-suffix=-3.1</samp> 300would result in ‘<samp>gcc</samp>’ being installed as 301<samp>/usr/local/bin/gcc-3.1</samp>. 302</p> 303</dd> 304<dt><code>--program-transform-name=<var>pattern</var></code></dt> 305<dd><p>Applies the ‘<samp>sed</samp>’ script <var>pattern</var> to be applied to the names 306of programs to install in <var>bindir</var> (see above). <var>pattern</var> has to 307consist of one or more basic ‘<samp>sed</samp>’ editing commands, separated by 308semicolons. For example, if you want the ‘<samp>gcc</samp>’ program name to be 309transformed to the installed program <samp>/usr/local/bin/myowngcc</samp> and 310the ‘<samp>g++</samp>’ program name to be transformed to 311<samp>/usr/local/bin/gspecial++</samp> without changing other program names, 312you could use the pattern 313<samp>--program-transform-name='s/^gcc$/myowngcc/; s/^g++$/gspecial++/'</samp> 314to achieve this effect. 315</p> 316<p>All three options can be combined and used together, resulting in more 317complex conversion patterns. As a basic rule, <var>prefix</var> (and 318<var>suffix</var>) are prepended (appended) before further transformations 319can happen with a special transformation script <var>pattern</var>. 320</p> 321<p>As currently implemented, this option only takes effect for native 322builds; cross compiler binaries’ names are not transformed even when a 323transformation is explicitly asked for by one of these options. 324</p> 325<p>For native builds, some of the installed programs are also installed 326with the target alias in front of their name, as in 327‘<samp>i686-pc-linux-gnu-gcc</samp>’. All of the above transformations happen 328before the target alias is prepended to the name—so, specifying 329<samp>--program-prefix=foo-</samp> and <samp>program-suffix=-3.1</samp>, the 330resulting binary would be installed as 331<samp>/usr/local/bin/i686-pc-linux-gnu-foo-gcc-3.1</samp>. 332</p> 333<p>As a last shortcoming, none of the installed Ada programs are 334transformed yet, which will be fixed in some time. 335</p> 336</dd> 337<dt><code>--with-local-prefix=<var>dirname</var></code></dt> 338<dd><p>Specify the 339installation directory for local include files. The default is 340<samp>/usr/local</samp>. Specify this option if you want the compiler to 341search directory <samp><var>dirname</var>/include</samp> for locally installed 342header files <em>instead</em> of <samp>/usr/local/include</samp>. 343</p> 344<p>You should specify <samp>--with-local-prefix</samp> <strong>only</strong> if your 345site has a different convention (not <samp>/usr/local</samp>) for where to put 346site-specific files. 347</p> 348<p>The default value for <samp>--with-local-prefix</samp> is <samp>/usr/local</samp> 349regardless of the value of <samp>--prefix</samp>. Specifying 350<samp>--prefix</samp> has no effect on which directory GCC searches for 351local header files. This may seem counterintuitive, but actually it is 352logical. 353</p> 354<p>The purpose of <samp>--prefix</samp> is to specify where to <em>install 355GCC</em>. The local header files in <samp>/usr/local/include</samp>—if you put 356any in that directory—are not part of GCC. They are part of other 357programs—perhaps many others. (GCC installs its own header files in 358another directory which is based on the <samp>--prefix</samp> value.) 359</p> 360<p>Both the local-prefix include directory and the GCC-prefix include 361directory are part of GCC’s “system include” directories. Although these 362two directories are not fixed, they need to be searched in the proper 363order for the correct processing of the include_next directive. The 364local-prefix include directory is searched before the GCC-prefix 365include directory. Another characteristic of system include directories 366is that pedantic warnings are turned off for headers in these directories. 367</p> 368<p>Some autoconf macros add <samp>-I <var>directory</var></samp> options to the 369compiler command line, to ensure that directories containing installed 370packages’ headers are searched. When <var>directory</var> is one of GCC’s 371system include directories, GCC will ignore the option so that system 372directories continue to be processed in the correct order. This 373may result in a search order different from what was specified but the 374directory will still be searched. 375</p> 376<p>GCC automatically searches for ordinary libraries using 377<code>GCC_EXEC_PREFIX</code>. Thus, when the same installation prefix is 378used for both GCC and packages, GCC will automatically search for 379both headers and libraries. This provides a configuration that is 380easy to use. GCC behaves in a manner similar to that when it is 381installed as a system compiler in <samp>/usr</samp>. 382</p> 383<p>Sites that need to install multiple versions of GCC may not want to 384use the above simple configuration. It is possible to use the 385<samp>--program-prefix</samp>, <samp>--program-suffix</samp> and 386<samp>--program-transform-name</samp> options to install multiple versions 387into a single directory, but it may be simpler to use different prefixes 388and the <samp>--with-local-prefix</samp> option to specify the location of the 389site-specific files for each version. It will then be necessary for 390users to specify explicitly the location of local site libraries 391(e.g., with <code>LIBRARY_PATH</code>). 392</p> 393<p>The same value can be used for both <samp>--with-local-prefix</samp> and 394<samp>--prefix</samp> provided it is not <samp>/usr</samp>. This can be used 395to avoid the default search of <samp>/usr/local/include</samp>. 396</p> 397<p><strong>Do not</strong> specify <samp>/usr</samp> as the <samp>--with-local-prefix</samp>! 398The directory you use for <samp>--with-local-prefix</samp> <strong>must not</strong> 399contain any of the system’s standard header files. If it did contain 400them, certain programs would be miscompiled (including GNU Emacs, on 401certain targets), because this would override and nullify the header 402file corrections made by the <code>fixincludes</code> script. 403</p> 404<p>Indications are that people who use this option use it based on mistaken 405ideas of what it is for. People use it as if it specified where to 406install part of GCC. Perhaps they make this assumption because 407installing GCC creates the directory. 408</p> 409</dd> 410<dt><code>--with-native-system-header-dir=<var>dirname</var></code></dt> 411<dd><p>Specifies that <var>dirname</var> is the directory that contains native system 412header files, rather than <samp>/usr/include</samp>. This option is most useful 413if you are creating a compiler that should be isolated from the system 414as much as possible. It is most commonly used with the 415<samp>--with-sysroot</samp> option and will cause GCC to search 416<var>dirname</var> inside the system root specified by that option. 417</p> 418</dd> 419<dt><code>--enable-shared[=<var>package</var>[,…]]</code></dt> 420<dd><p>Build shared versions of libraries, if shared libraries are supported on 421the target platform. Unlike GCC 2.95.x and earlier, shared libraries 422are enabled by default on all platforms that support shared libraries. 423</p> 424<p>If a list of packages is given as an argument, build shared libraries 425only for the listed packages. For other packages, only static libraries 426will be built. Package names currently recognized in the GCC tree are 427‘<samp>libgcc</samp>’ (also known as ‘<samp>gcc</samp>’), ‘<samp>libstdc++</samp>’ (not 428‘<samp>libstdc++-v3</samp>’), ‘<samp>libffi</samp>’, ‘<samp>zlib</samp>’, ‘<samp>boehm-gc</samp>’, 429‘<samp>ada</samp>’, ‘<samp>libada</samp>’, ‘<samp>libjava</samp>’, ‘<samp>libgo</samp>’, and ‘<samp>libobjc</samp>’. 430Note ‘<samp>libiberty</samp>’ does not support shared libraries at all. 431</p> 432<p>Use <samp>--disable-shared</samp> to build only static libraries. Note that 433<samp>--disable-shared</samp> does not accept a list of package names as 434argument, only <samp>--enable-shared</samp> does. 435</p> 436<p>Contrast with <samp>--enable-host-shared</samp>, which affects <em>host</em> 437code. 438</p> 439</dd> 440<dt><code>--enable-host-shared</code></dt> 441<dd><p>Specify that the <em>host</em> code should be built into position-independent 442machine code (with -fPIC), allowing it to be used within shared libraries, 443but yielding a slightly slower compiler. 444</p> 445<p>This option is required when building the libgccjit.so library. 446</p> 447<p>Contrast with <samp>--enable-shared</samp>, which affects <em>target</em> 448libraries. 449</p> 450</dd> 451<dt><code><a name="with_002dgnu_002das"></a>--with-gnu-as</code></dt> 452<dd><p>Specify that the compiler should assume that the 453assembler it finds is the GNU assembler. However, this does not modify 454the rules to find an assembler and will result in confusion if the 455assembler found is not actually the GNU assembler. (Confusion may also 456result if the compiler finds the GNU assembler but has not been 457configured with <samp>--with-gnu-as</samp>.) If you have more than one 458assembler installed on your system, you may want to use this option in 459connection with <samp>--with-as=<var>pathname</var></samp> or 460<samp>--with-build-time-tools=<var>pathname</var></samp>. 461</p> 462<p>The following systems are the only ones where it makes a difference 463whether you use the GNU assembler. On any other system, 464<samp>--with-gnu-as</samp> has no effect. 465</p> 466<ul> 467<li> ‘<samp>hppa1.0-<var>any</var>-<var>any</var></samp>’ 468</li><li> ‘<samp>hppa1.1-<var>any</var>-<var>any</var></samp>’ 469</li><li> ‘<samp>sparc-sun-solaris2.<var>any</var></samp>’ 470</li><li> ‘<samp>sparc64-<var>any</var>-solaris2.<var>any</var></samp>’ 471</li></ul> 472 473</dd> 474<dt><code><a name="with_002das"></a>--with-as=<var>pathname</var></code></dt> 475<dd><p>Specify that the compiler should use the assembler pointed to by 476<var>pathname</var>, rather than the one found by the standard rules to find 477an assembler, which are: 478</p><ul> 479<li> Unless GCC is being built with a cross compiler, check the 480<samp><var>libexec</var>/gcc/<var>target</var>/<var>version</var></samp> directory. 481<var>libexec</var> defaults to <samp><var>exec-prefix</var>/libexec</samp>; 482<var>exec-prefix</var> defaults to <var>prefix</var>, which 483defaults to <samp>/usr/local</samp> unless overridden by the 484<samp>--prefix=<var>pathname</var></samp> switch described above. <var>target</var> 485is the target system triple, such as ‘<samp>sparc-sun-solaris2.7</samp>’, and 486<var>version</var> denotes the GCC version, such as 3.0. 487 488</li><li> If the target system is the same that you are building on, check 489operating system specific directories (e.g. <samp>/usr/ccs/bin</samp> on 490Sun Solaris 2). 491 492</li><li> Check in the <code>PATH</code> for a tool whose name is prefixed by the 493target system triple. 494 495</li><li> Check in the <code>PATH</code> for a tool whose name is not prefixed by the 496target system triple, if the host and target system triple are 497the same (in other words, we use a host tool if it can be used for 498the target as well). 499</li></ul> 500 501<p>You may want to use <samp>--with-as</samp> if no assembler 502is installed in the directories listed above, or if you have multiple 503assemblers installed and want to choose one that is not found by the 504above rules. 505</p> 506</dd> 507<dt><code><a name="with_002dgnu_002dld"></a>--with-gnu-ld</code></dt> 508<dd><p>Same as <a href="#with-gnu-as"><samp>--with-gnu-as</samp></a> 509but for the linker. 510</p> 511</dd> 512<dt><code>--with-ld=<var>pathname</var></code></dt> 513<dd><p>Same as <a href="#with-as"><samp>--with-as</samp></a> 514but for the linker. 515</p> 516</dd> 517<dt><code>--with-stabs</code></dt> 518<dd><p>Specify that stabs debugging 519information should be used instead of whatever format the host normally 520uses. Normally GCC uses the same debug format as the host system. 521</p> 522<p>On MIPS based systems and on Alphas, you must specify whether you want 523GCC to create the normal ECOFF debugging format, or to use BSD-style 524stabs passed through the ECOFF symbol table. The normal ECOFF debug 525format cannot fully handle languages other than C. BSD stabs format can 526handle other languages, but it only works with the GNU debugger GDB. 527</p> 528<p>Normally, GCC uses the ECOFF debugging format by default; if you 529prefer BSD stabs, specify <samp>--with-stabs</samp> when you configure GCC. 530</p> 531<p>No matter which default you choose when you configure GCC, the user 532can use the <samp>-gcoff</samp> and <samp>-gstabs+</samp> options to specify explicitly 533the debug format for a particular compilation. 534</p> 535<p><samp>--with-stabs</samp> is meaningful on the ISC system on the 386, also, if 536<samp>--with-gas</samp> is used. It selects use of stabs debugging 537information embedded in COFF output. This kind of debugging information 538supports C++ well; ordinary COFF debugging information does not. 539</p> 540<p><samp>--with-stabs</samp> is also meaningful on 386 systems running SVR4. It 541selects use of stabs debugging information embedded in ELF output. The 542C++ compiler currently (2.6.0) does not support the DWARF debugging 543information normally used on 386 SVR4 platforms; stabs provide a 544workable alternative. This requires gas and gdb, as the normal SVR4 545tools can not generate or interpret stabs. 546</p> 547</dd> 548<dt><code>--with-tls=<var>dialect</var></code></dt> 549<dd><p>Specify the default TLS dialect, for systems were there is a choice. 550For ARM targets, possible values for <var>dialect</var> are <code>gnu</code> or 551<code>gnu2</code>, which select between the original GNU dialect and the GNU TLS 552descriptor-based dialect. 553</p> 554</dd> 555<dt><code>--enable-multiarch</code></dt> 556<dd><p>Specify whether to enable or disable multiarch support. The default is 557to check for glibc start files in a multiarch location, and enable it 558if the files are found. The auto detection is enabled for native builds, 559and for cross builds configured with <samp>--with-sysroot</samp>, and without 560<samp>--with-native-system-header-dir</samp>. 561More documentation about multiarch can be found at 562<a href="http://wiki.debian.org/Multiarch">http://wiki.debian.org/Multiarch</a>. 563</p> 564</dd> 565<dt><code>--enable-sjlj-exceptions</code></dt> 566<dd><p>Force use of the <code>setjmp</code>/<code>longjmp</code>-based scheme for exceptions. 567‘<samp>configure</samp>’ ordinarily picks the correct value based on the platform. 568Only use this option if you are sure you need a different setting. 569</p> 570</dd> 571<dt><code>--enable-vtable-verify</code></dt> 572<dd><p>Specify whether to enable or disable the vtable verification feature. 573Enabling this feature causes libstdc++ to be built with its virtual calls 574in verifiable mode. This means that, when linked with libvtv, every 575virtual call in libstdc++ will verify the vtable pointer through which the 576call will be made before actually making the call. If not linked with libvtv, 577the verifier will call stub functions (in libstdc++ itself) and do nothing. 578If vtable verification is disabled, then libstdc++ is not built with its 579virtual calls in verifiable mode at all. However the libvtv library will 580still be built (see <samp>--disable-libvtv</samp> to turn off building libvtv). 581<samp>--disable-vtable-verify</samp> is the default. 582</p> 583</dd> 584<dt><code>--disable-multilib</code></dt> 585<dd><p>Specify that multiple target 586libraries to support different target variants, calling 587conventions, etc. should not be built. The default is to build a 588predefined set of them. 589</p> 590<p>Some targets provide finer-grained control over which multilibs are built 591(e.g., <samp>--disable-softfloat</samp>): 592</p><dl compact="compact"> 593<dt><code>arm-*-*</code></dt> 594<dd><p>fpu, 26bit, underscore, interwork, biendian, nofmult. 595</p> 596</dd> 597<dt><code>m68*-*-*</code></dt> 598<dd><p>softfloat, m68881, m68000, m68020. 599</p> 600</dd> 601<dt><code>mips*-*-*</code></dt> 602<dd><p>single-float, biendian, softfloat. 603</p> 604</dd> 605<dt><code>powerpc*-*-*, rs6000*-*-*</code></dt> 606<dd><p>aix64, pthread, softfloat, powercpu, powerpccpu, powerpcos, biendian, 607sysv, aix. 608</p> 609</dd> 610</dl> 611 612</dd> 613<dt><code>--with-multilib-list=<var>list</var></code></dt> 614<dt><code>--without-multilib-list</code></dt> 615<dd><p>Specify what multilibs to build. 616Currently only implemented for sh*-*-* and x86-64-*-linux*. 617</p> 618<dl compact="compact"> 619<dt><code>sh*-*-*</code></dt> 620<dd><p><var>list</var> is a comma separated list of CPU names. These must be of the 621form <code>sh*</code> or <code>m*</code> (in which case they match the compiler option 622for that processor). The list should not contain any endian options - 623these are handled by <samp>--with-endian</samp>. 624</p> 625<p>If <var>list</var> is empty, then there will be no multilibs for extra 626processors. The multilib for the secondary endian remains enabled. 627</p> 628<p>As a special case, if an entry in the list starts with a <code>!</code> 629(exclamation point), then it is added to the list of excluded multilibs. 630Entries of this sort should be compatible with ‘<samp>MULTILIB_EXCLUDES</samp>’ 631(once the leading <code>!</code> has been stripped). 632</p> 633<p>If <samp>--with-multilib-list</samp> is not given, then a default set of 634multilibs is selected based on the value of <samp>--target</samp>. This is 635usually the complete set of libraries, but some targets imply a more 636specialized subset. 637</p> 638<p>Example 1: to configure a compiler for SH4A only, but supporting both 639endians, with little endian being the default: 640</p><div class="smallexample"> 641<pre class="smallexample">--with-cpu=sh4a --with-endian=little,big --with-multilib-list= 642</pre></div> 643 644<p>Example 2: to configure a compiler for both SH4A and SH4AL-DSP, but with 645only little endian SH4AL: 646</p><div class="smallexample"> 647<pre class="smallexample">--with-cpu=sh4a --with-endian=little,big \ 648--with-multilib-list=sh4al,!mb/m4al 649</pre></div> 650 651</dd> 652<dt><code>x86-64-*-linux*</code></dt> 653<dd><p><var>list</var> is a comma separated list of <code>m32</code>, <code>m64</code> and 654<code>mx32</code> to enable 32-bit, 64-bit and x32 run-time libraries, 655respectively. If <var>list</var> is empty, then there will be no multilibs 656and only the default run-time library will be enabled. 657</p> 658<p>If <samp>--with-multilib-list</samp> is not given, then only 32-bit and 65964-bit run-time libraries will be enabled. 660</p></dd> 661</dl> 662 663</dd> 664<dt><code>--with-endian=<var>endians</var></code></dt> 665<dd><p>Specify what endians to use. 666Currently only implemented for sh*-*-*. 667</p> 668<p><var>endians</var> may be one of the following: 669</p><dl compact="compact"> 670<dt><code>big</code></dt> 671<dd><p>Use big endian exclusively. 672</p></dd> 673<dt><code>little</code></dt> 674<dd><p>Use little endian exclusively. 675</p></dd> 676<dt><code>big,little</code></dt> 677<dd><p>Use big endian by default. Provide a multilib for little endian. 678</p></dd> 679<dt><code>little,big</code></dt> 680<dd><p>Use little endian by default. Provide a multilib for big endian. 681</p></dd> 682</dl> 683 684</dd> 685<dt><code>--enable-threads</code></dt> 686<dd><p>Specify that the target 687supports threads. This affects the Objective-C compiler and runtime 688library, and exception handling for other languages like C++ and Java. 689On some systems, this is the default. 690</p> 691<p>In general, the best (and, in many cases, the only known) threading 692model available will be configured for use. Beware that on some 693systems, GCC has not been taught what threading models are generally 694available for the system. In this case, <samp>--enable-threads</samp> is an 695alias for <samp>--enable-threads=single</samp>. 696</p> 697</dd> 698<dt><code>--disable-threads</code></dt> 699<dd><p>Specify that threading support should be disabled for the system. 700This is an alias for <samp>--enable-threads=single</samp>. 701</p> 702</dd> 703<dt><code>--enable-threads=<var>lib</var></code></dt> 704<dd><p>Specify that 705<var>lib</var> is the thread support library. This affects the Objective-C 706compiler and runtime library, and exception handling for other languages 707like C++ and Java. The possibilities for <var>lib</var> are: 708</p> 709<dl compact="compact"> 710<dt><code>aix</code></dt> 711<dd><p>AIX thread support. 712</p></dd> 713<dt><code>dce</code></dt> 714<dd><p>DCE thread support. 715</p></dd> 716<dt><code>lynx</code></dt> 717<dd><p>LynxOS thread support. 718</p></dd> 719<dt><code>mipssde</code></dt> 720<dd><p>MIPS SDE thread support. 721</p></dd> 722<dt><code>no</code></dt> 723<dd><p>This is an alias for ‘<samp>single</samp>’. 724</p></dd> 725<dt><code>posix</code></dt> 726<dd><p>Generic POSIX/Unix98 thread support. 727</p></dd> 728<dt><code>rtems</code></dt> 729<dd><p>RTEMS thread support. 730</p></dd> 731<dt><code>single</code></dt> 732<dd><p>Disable thread support, should work for all platforms. 733</p></dd> 734<dt><code>tpf</code></dt> 735<dd><p>TPF thread support. 736</p></dd> 737<dt><code>vxworks</code></dt> 738<dd><p>VxWorks thread support. 739</p></dd> 740<dt><code>win32</code></dt> 741<dd><p>Microsoft Win32 API thread support. 742</p></dd> 743</dl> 744 745</dd> 746<dt><code>--enable-tls</code></dt> 747<dd><p>Specify that the target supports TLS (Thread Local Storage). Usually 748configure can correctly determine if TLS is supported. In cases where 749it guesses incorrectly, TLS can be explicitly enabled or disabled with 750<samp>--enable-tls</samp> or <samp>--disable-tls</samp>. This can happen if 751the assembler supports TLS but the C library does not, or if the 752assumptions made by the configure test are incorrect. 753</p> 754</dd> 755<dt><code>--disable-tls</code></dt> 756<dd><p>Specify that the target does not support TLS. 757This is an alias for <samp>--enable-tls=no</samp>. 758</p> 759</dd> 760<dt><code>--with-cpu=<var>cpu</var></code></dt> 761<dt><code>--with-cpu-32=<var>cpu</var></code></dt> 762<dt><code>--with-cpu-64=<var>cpu</var></code></dt> 763<dd><p>Specify which cpu variant the compiler should generate code for by default. 764<var>cpu</var> will be used as the default value of the <samp>-mcpu=</samp> switch. 765This option is only supported on some targets, including ARC, ARM, i386, M68k, 766PowerPC, and SPARC. It is mandatory for ARC. The <samp>--with-cpu-32</samp> and 767<samp>--with-cpu-64</samp> options specify separate default CPUs for 76832-bit and 64-bit modes; these options are only supported for i386, 769x86-64 and PowerPC. 770</p> 771</dd> 772<dt><code>--with-schedule=<var>cpu</var></code></dt> 773<dt><code>--with-arch=<var>cpu</var></code></dt> 774<dt><code>--with-arch-32=<var>cpu</var></code></dt> 775<dt><code>--with-arch-64=<var>cpu</var></code></dt> 776<dt><code>--with-tune=<var>cpu</var></code></dt> 777<dt><code>--with-tune-32=<var>cpu</var></code></dt> 778<dt><code>--with-tune-64=<var>cpu</var></code></dt> 779<dt><code>--with-abi=<var>abi</var></code></dt> 780<dt><code>--with-fpu=<var>type</var></code></dt> 781<dt><code>--with-float=<var>type</var></code></dt> 782<dd><p>These configure options provide default values for the <samp>-mschedule=</samp>, 783<samp>-march=</samp>, <samp>-mtune=</samp>, <samp>-mabi=</samp>, and <samp>-mfpu=</samp> 784options and for <samp>-mhard-float</samp> or <samp>-msoft-float</samp>. As with 785<samp>--with-cpu</samp>, which switches will be accepted and acceptable values 786of the arguments depend on the target. 787</p> 788</dd> 789<dt><code>--with-mode=<var>mode</var></code></dt> 790<dd><p>Specify if the compiler should default to <samp>-marm</samp> or <samp>-mthumb</samp>. 791This option is only supported on ARM targets. 792</p> 793</dd> 794<dt><code>--with-stack-offset=<var>num</var></code></dt> 795<dd><p>This option sets the default for the -mstack-offset=<var>num</var> option, 796and will thus generally also control the setting of this option for 797libraries. This option is only supported on Epiphany targets. 798</p> 799</dd> 800<dt><code>--with-fpmath=<var>isa</var></code></dt> 801<dd><p>This options sets <samp>-mfpmath=sse</samp> by default and specifies the default 802ISA for floating-point arithmetics. You can select either ‘<samp>sse</samp>’ which 803enables <samp>-msse2</samp> or ‘<samp>avx</samp>’ which enables <samp>-mavx</samp> by default. 804This option is only supported on i386 and x86-64 targets. 805</p> 806</dd> 807<dt><code>--with-fp-32=<var>mode</var></code></dt> 808<dd><p>On MIPS targets, set the default value for the <samp>-mfp</samp> option when using 809the o32 ABI. The possibilities for <var>mode</var> are: 810</p><dl compact="compact"> 811<dt><code>32</code></dt> 812<dd><p>Use the o32 FP32 ABI extension, as with the <samp>-mfp32</samp> command-line 813option. 814</p></dd> 815<dt><code>xx</code></dt> 816<dd><p>Use the o32 FPXX ABI extension, as with the <samp>-mfpxx</samp> command-line 817option. 818</p></dd> 819<dt><code>64</code></dt> 820<dd><p>Use the o32 FP64 ABI extension, as with the <samp>-mfp64</samp> command-line 821option. 822</p></dd> 823</dl> 824<p>In the absence of this configuration option the default is to use the o32 825FP32 ABI extension. 826</p> 827</dd> 828<dt><code>--with-odd-spreg-32</code></dt> 829<dd><p>On MIPS targets, set the <samp>-modd-spreg</samp> option by default when using 830the o32 ABI. 831</p> 832</dd> 833<dt><code>--without-odd-spreg-32</code></dt> 834<dd><p>On MIPS targets, set the <samp>-mno-odd-spreg</samp> option by default when using 835the o32 ABI. This is normally used in conjunction with 836<samp>--with-fp-32=64</samp> in order to target the o32 FP64A ABI extension. 837</p> 838</dd> 839<dt><code>--with-nan=<var>encoding</var></code></dt> 840<dd><p>On MIPS targets, set the default encoding convention to use for the 841special not-a-number (NaN) IEEE 754 floating-point data. The 842possibilities for <var>encoding</var> are: 843</p><dl compact="compact"> 844<dt><code>legacy</code></dt> 845<dd><p>Use the legacy encoding, as with the <samp>-mnan=legacy</samp> command-line 846option. 847</p></dd> 848<dt><code>2008</code></dt> 849<dd><p>Use the 754-2008 encoding, as with the <samp>-mnan=2008</samp> command-line 850option. 851</p></dd> 852</dl> 853<p>To use this configuration option you must have an assembler version 854installed that supports the <samp>-mnan=</samp> command-line option too. 855In the absence of this configuration option the default convention is 856the legacy encoding, as when neither of the <samp>-mnan=2008</samp> and 857<samp>-mnan=legacy</samp> command-line options has been used. 858</p> 859</dd> 860<dt><code>--with-divide=<var>type</var></code></dt> 861<dd><p>Specify how the compiler should generate code for checking for 862division by zero. This option is only supported on the MIPS target. 863The possibilities for <var>type</var> are: 864</p><dl compact="compact"> 865<dt><code>traps</code></dt> 866<dd><p>Division by zero checks use conditional traps (this is the default on 867systems that support conditional traps). 868</p></dd> 869<dt><code>breaks</code></dt> 870<dd><p>Division by zero checks use the break instruction. 871</p></dd> 872</dl> 873 874 875</dd> 876<dt><code>--with-llsc</code></dt> 877<dd><p>On MIPS targets, make <samp>-mllsc</samp> the default when no 878<samp>-mno-llsc</samp> option is passed. This is the default for 879Linux-based targets, as the kernel will emulate them if the ISA does 880not provide them. 881</p> 882</dd> 883<dt><code>--without-llsc</code></dt> 884<dd><p>On MIPS targets, make <samp>-mno-llsc</samp> the default when no 885<samp>-mllsc</samp> option is passed. 886</p> 887</dd> 888<dt><code>--with-synci</code></dt> 889<dd><p>On MIPS targets, make <samp>-msynci</samp> the default when no 890<samp>-mno-synci</samp> option is passed. 891</p> 892</dd> 893<dt><code>--without-synci</code></dt> 894<dd><p>On MIPS targets, make <samp>-mno-synci</samp> the default when no 895<samp>-msynci</samp> option is passed. This is the default. 896</p> 897</dd> 898<dt><code>--with-mips-plt</code></dt> 899<dd><p>On MIPS targets, make use of copy relocations and PLTs. 900These features are extensions to the traditional 901SVR4-based MIPS ABIs and require support from GNU binutils 902and the runtime C library. 903</p> 904</dd> 905<dt><code>--enable-__cxa_atexit</code></dt> 906<dd><p>Define if you want to use __cxa_atexit, rather than atexit, to 907register C++ destructors for local statics and global objects. 908This is essential for fully standards-compliant handling of 909destructors, but requires __cxa_atexit in libc. This option is currently 910only available on systems with GNU libc. When enabled, this will cause 911<samp>-fuse-cxa-atexit</samp> to be passed by default. 912</p> 913</dd> 914<dt><code>--enable-gnu-indirect-function</code></dt> 915<dd><p>Define if you want to enable the <code>ifunc</code> attribute. This option is 916currently only available on systems with GNU libc on certain targets. 917</p> 918</dd> 919<dt><code>--enable-target-optspace</code></dt> 920<dd><p>Specify that target 921libraries should be optimized for code space instead of code speed. 922This is the default for the m32r platform. 923</p> 924</dd> 925<dt><code>--with-cpp-install-dir=<var>dirname</var></code></dt> 926<dd><p>Specify that the user visible <code>cpp</code> program should be installed 927in <samp><var>prefix</var>/<var>dirname</var>/cpp</samp>, in addition to <var>bindir</var>. 928</p> 929</dd> 930<dt><code>--enable-comdat</code></dt> 931<dd><p>Enable COMDAT group support. This is primarily used to override the 932automatically detected value. 933</p> 934</dd> 935<dt><code>--enable-initfini-array</code></dt> 936<dd><p>Force the use of sections <code>.init_array</code> and <code>.fini_array</code> 937(instead of <code>.init</code> and <code>.fini</code>) for constructors and 938destructors. Option <samp>--disable-initfini-array</samp> has the 939opposite effect. If neither option is specified, the configure script 940will try to guess whether the <code>.init_array</code> and 941<code>.fini_array</code> sections are supported and, if they are, use them. 942</p> 943</dd> 944<dt><code>--enable-link-mutex</code></dt> 945<dd><p>When building GCC, use a mutex to avoid linking the compilers for 946multiple languages at the same time, to avoid thrashing on build 947systems with limited free memory. The default is not to use such a mutex. 948</p> 949</dd> 950<dt><code>--enable-maintainer-mode</code></dt> 951<dd><p>The build rules that regenerate the Autoconf and Automake output files as 952well as the GCC master message catalog <samp>gcc.pot</samp> are normally 953disabled. This is because it can only be rebuilt if the complete source 954tree is present. If you have changed the sources and want to rebuild the 955catalog, configuring with <samp>--enable-maintainer-mode</samp> will enable 956this. Note that you need a recent version of the <code>gettext</code> tools 957to do so. 958</p> 959</dd> 960<dt><code>--disable-bootstrap</code></dt> 961<dd><p>For a native build, the default configuration is to perform 962a 3-stage bootstrap of the compiler when ‘<samp>make</samp>’ is invoked, 963testing that GCC can compile itself correctly. If you want to disable 964this process, you can configure with <samp>--disable-bootstrap</samp>. 965</p> 966</dd> 967<dt><code>--enable-bootstrap</code></dt> 968<dd><p>In special cases, you may want to perform a 3-stage build 969even if the target and host triplets are different. 970This is possible when the host can run code compiled for 971the target (e.g. host is i686-linux, target is i486-linux). 972Starting from GCC 4.2, to do this you have to configure explicitly 973with <samp>--enable-bootstrap</samp>. 974</p> 975</dd> 976<dt><code>--enable-generated-files-in-srcdir</code></dt> 977<dd><p>Neither the .c and .h files that are generated from Bison and flex nor the 978info manuals and man pages that are built from the .texi files are present 979in the SVN development tree. When building GCC from that development tree, 980or from one of our snapshots, those generated files are placed in your 981build directory, which allows for the source to be in a readonly 982directory. 983</p> 984<p>If you configure with <samp>--enable-generated-files-in-srcdir</samp> then those 985generated files will go into the source directory. This is mainly intended 986for generating release or prerelease tarballs of the GCC sources, since it 987is not a requirement that the users of source releases to have flex, Bison, 988or makeinfo. 989</p> 990</dd> 991<dt><code>--enable-version-specific-runtime-libs</code></dt> 992<dd><p>Specify 993that runtime libraries should be installed in the compiler specific 994subdirectory (<samp><var>libdir</var>/gcc</samp>) rather than the usual places. In 995addition, ‘<samp>libstdc++</samp>’’s include files will be installed into 996<samp><var>libdir</var></samp> unless you overruled it by using 997<samp>--with-gxx-include-dir=<var>dirname</var></samp>. Using this option is 998particularly useful if you intend to use several versions of GCC in 999parallel. This is currently supported by ‘<samp>libgfortran</samp>’, 1000‘<samp>libjava</samp>’, ‘<samp>libstdc++</samp>’, and ‘<samp>libobjc</samp>’. 1001</p> 1002</dd> 1003<dt><code><a name="WithAixSoname"></a>--with-aix-soname=‘<samp>aix</samp>’, ‘<samp>svr4</samp>’ or ‘<samp>both</samp>’</code></dt> 1004<dd><p>Traditional AIX shared library versioning (versioned <code>Shared Object</code> 1005files as members of unversioned <code>Archive Library</code> files named 1006‘<samp>lib.a</samp>’) causes numerous headaches for package managers. However, 1007<code>Import Files</code> as members of <code>Archive Library</code> files allow for 1008<strong>filename-based versioning</strong> of shared libraries as seen on Linux/SVR4, 1009where this is called the "SONAME". But as they prevent static linking, 1010<code>Import Files</code> may be used with <code>Runtime Linking</code> only, where the 1011linker does search for ‘<samp>libNAME.so</samp>’ before ‘<samp>libNAME.a</samp>’ library 1012filenames with the ‘<samp>-lNAME</samp>’ linker flag. 1013</p> 1014<a name="AixLdCommand"></a><p>For detailed information please refer to the AIX 1015<a href="http://www-01.ibm.com/support/knowledgecenter/search/%22the%20ld%20command%2C%20also%20called%20the%20linkage%20editor%20or%20binder%22">ld 1016Command</a> reference. 1017</p> 1018<p>As long as shared library creation is enabled, upon: 1019</p><dl compact="compact"> 1020<dt><code>--with-aix-soname=aix</code></dt> 1021<dt><code>--with-aix-soname=both</code></dt> 1022<dd><p>A (traditional AIX) <code>Shared Archive Library</code> file is created: 1023 </p><ul> 1024<li> using the ‘<samp>libNAME.a</samp>’ filename scheme 1025 </li><li> with the <code>Shared Object</code> file as archive member named 1026 ‘<samp>libNAME.so.V</samp>’ (except for ‘<samp>libgcc_s</samp>’, where the <code>Shared 1027 Object</code> file is named ‘<samp>shr.o</samp>’ for backwards compatibility), which 1028 <ul class="no-bullet"> 1029<li>- is used for runtime loading from inside the ‘<samp>libNAME.a</samp>’ file 1030 </li><li>- is used for dynamic loading via 1031 <code>dlopen("libNAME.a(libNAME.so.V)", RTLD_MEMBER)</code> 1032 </li><li>- is used for shared linking 1033 </li><li>- is used for static linking, so no separate <code>Static Archive 1034 Library</code> file is needed 1035 </li></ul> 1036</li></ul> 1037</dd> 1038<dt><code>--with-aix-soname=both</code></dt> 1039<dt><code>--with-aix-soname=svr4</code></dt> 1040<dd><p>A (second) <code>Shared Archive Library</code> file is created: 1041 </p><ul> 1042<li> using the ‘<samp>libNAME.so.V</samp>’ filename scheme 1043 </li><li> with the <code>Shared Object</code> file as archive member named 1044 ‘<samp>shr.o</samp>’, which 1045 <ul class="no-bullet"> 1046<li>- is created with the <code>-G linker flag</code> 1047 </li><li>- has the <code>F_LOADONLY</code> flag set 1048 </li><li>- is used for runtime loading from inside the ‘<samp>libNAME.so.V</samp>’ file 1049 </li><li>- is used for dynamic loading via <code>dlopen("libNAME.so.V(shr.o)", 1050 RTLD_MEMBER)</code> 1051 </li></ul> 1052</li><li> with the <code>Import File</code> as archive member named ‘<samp>shr.imp</samp>’, 1053 which 1054 <ul class="no-bullet"> 1055<li>- refers to ‘<samp>libNAME.so.V(shr.o)</samp>’ as the "SONAME", to be recorded 1056 in the <code>Loader Section</code> of subsequent binaries 1057 </li><li>- indicates whether ‘<samp>libNAME.so.V(shr.o)</samp>’ is 32 or 64 bit 1058 </li><li>- lists all the public symbols exported by ‘<samp>lib.so.V(shr.o)</samp>’, 1059 eventually decorated with the <code>‘<samp>weak</samp>’ Keyword</code> 1060 </li><li>- is necessary for shared linking against ‘<samp>lib.so.V(shr.o)</samp>’ 1061 </li></ul> 1062</li></ul> 1063<p>A symbolic link using the ‘<samp>libNAME.so</samp>’ filename scheme is created: 1064 </p><ul> 1065<li> pointing to the ‘<samp>libNAME.so.V</samp>’ <code>Shared Archive Library</code> file 1066 </li><li> to permit the <code>ld Command</code> to find ‘<samp>lib.so.V(shr.imp)</samp>’ via 1067 the ‘<samp>-lNAME</samp>’ argument (requires <code>Runtime Linking</code> to be enabled) 1068 </li><li> to permit dynamic loading of ‘<samp>lib.so.V(shr.o)</samp>’ without the need 1069 to specify the version number via <code>dlopen("libNAME.so(shr.o)", 1070 RTLD_MEMBER)</code> 1071 </li></ul> 1072</dd> 1073</dl> 1074 1075<p>As long as static library creation is enabled, upon: 1076</p><dl compact="compact"> 1077<dt><code>--with-aix-soname=svr4</code></dt> 1078<dd><p>A <code>Static Archive Library</code> is created: 1079 </p><ul> 1080<li> using the ‘<samp>libNAME.a</samp>’ filename scheme 1081 </li><li> with all the <code>Static Object</code> files as archive members, which 1082 <ul class="no-bullet"> 1083<li>- are used for static linking 1084 </li></ul> 1085</li></ul> 1086</dd> 1087</dl> 1088 1089<p>While the aix-soname=‘<samp>svr4</samp>’ option does not create <code>Shared Object</code> 1090files as members of unversioned <code>Archive Library</code> files any more, package 1091managers still are responsible to 1092<a href="./specific.html#TransferAixShobj">transfer</a> <code>Shared Object</code> files 1093found as member of a previously installed unversioned <code>Archive Library</code> 1094file into the newly installed <code>Archive Library</code> file with the same 1095filename. 1096</p> 1097<p><em>WARNING:</em> Creating <code>Shared Object</code> files with <code>Runtime Linking</code> 1098enabled may bloat the TOC, eventually leading to <code>TOC overflow</code> errors, 1099requiring the use of either the <samp>-Wl,-bbigtoc</samp> linker flag (seen to 1100break with the <code>GDB</code> debugger) or some of the TOC-related compiler flags, 1101see “RS/6000 and PowerPC Options” in the main manual. 1102</p> 1103<p><samp>--with-aix-soname</samp> is currently supported by ‘<samp>libgcc_s</samp>’ only, so 1104this option is still experimental and not for normal use yet. 1105</p> 1106<p>Default is the traditional behaviour <samp>--with-aix-soname=‘<samp>aix</samp>’</samp>. 1107</p> 1108</dd> 1109<dt><code>--enable-languages=<var>lang1</var>,<var>lang2</var>,…</code></dt> 1110<dd><p>Specify that only a particular subset of compilers and 1111their runtime libraries should be built. For a list of valid values for 1112<var>langN</var> you can issue the following command in the 1113<samp>gcc</samp> directory of your GCC source tree:<br> 1114</p><div class="smallexample"> 1115<pre class="smallexample">grep language= */config-lang.in 1116</pre></div> 1117<p>Currently, you can use any of the following: 1118<code>all</code>, <code>ada</code>, <code>c</code>, <code>c++</code>, <code>fortran</code>, 1119<code>go</code>, <code>java</code>, <code>objc</code>, <code>obj-c++</code>. 1120Building the Ada compiler has special requirements, see below. 1121If you do not pass this flag, or specify the option <code>all</code>, then all 1122default languages available in the <samp>gcc</samp> sub-tree will be configured. 1123Ada, Go and Objective-C++ are not default languages; the rest are. 1124</p> 1125</dd> 1126<dt><code>--enable-stage1-languages=<var>lang1</var>,<var>lang2</var>,…</code></dt> 1127<dd><p>Specify that a particular subset of compilers and their runtime 1128libraries should be built with the system C compiler during stage 1 of 1129the bootstrap process, rather than only in later stages with the 1130bootstrapped C compiler. The list of valid values is the same as for 1131<samp>--enable-languages</samp>, and the option <code>all</code> will select all 1132of the languages enabled by <samp>--enable-languages</samp>. This option is 1133primarily useful for GCC development; for instance, when a development 1134version of the compiler cannot bootstrap due to compiler bugs, or when 1135one is debugging front ends other than the C front end. When this 1136option is used, one can then build the target libraries for the 1137specified languages with the stage-1 compiler by using <code>make 1138stage1-bubble all-target</code>, or run the testsuite on the stage-1 compiler 1139for the specified languages using <code>make stage1-start check-gcc</code>. 1140</p> 1141</dd> 1142<dt><code>--disable-libada</code></dt> 1143<dd><p>Specify that the run-time libraries and tools used by GNAT should not 1144be built. This can be useful for debugging, or for compatibility with 1145previous Ada build procedures, when it was required to explicitly 1146do a ‘<samp>make -C gcc gnatlib_and_tools</samp>’. 1147</p> 1148</dd> 1149<dt><code>--disable-libsanitizer</code></dt> 1150<dd><p>Specify that the run-time libraries for the various sanitizers should 1151not be built. 1152</p> 1153</dd> 1154<dt><code>--disable-libssp</code></dt> 1155<dd><p>Specify that the run-time libraries for stack smashing protection 1156should not be built. 1157</p> 1158</dd> 1159<dt><code>--disable-libquadmath</code></dt> 1160<dd><p>Specify that the GCC quad-precision math library should not be built. 1161On some systems, the library is required to be linkable when building 1162the Fortran front end, unless <samp>--disable-libquadmath-support</samp> 1163is used. 1164</p> 1165</dd> 1166<dt><code>--disable-libquadmath-support</code></dt> 1167<dd><p>Specify that the Fortran front end and <code>libgfortran</code> do not add 1168support for <code>libquadmath</code> on systems supporting it. 1169</p> 1170</dd> 1171<dt><code>--disable-libgomp</code></dt> 1172<dd><p>Specify that the GNU Offloading and Multi Processing Runtime Library 1173should not be built. 1174</p> 1175</dd> 1176<dt><code>--disable-libvtv</code></dt> 1177<dd><p>Specify that the run-time libraries used by vtable verification 1178should not be built. 1179</p> 1180</dd> 1181<dt><code>--with-dwarf2</code></dt> 1182<dd><p>Specify that the compiler should 1183use DWARF 2 debugging information as the default. 1184</p> 1185</dd> 1186<dt><code>--enable-targets=all</code></dt> 1187<dt><code>--enable-targets=<var>target_list</var></code></dt> 1188<dd><p>Some GCC targets, e.g. powerpc64-linux, build bi-arch compilers. 1189These are compilers that are able to generate either 64-bit or 32-bit 1190code. Typically, the corresponding 32-bit target, e.g. 1191powerpc-linux for powerpc64-linux, only generates 32-bit code. This 1192option enables the 32-bit target to be a bi-arch compiler, which is 1193useful when you want a bi-arch compiler that defaults to 32-bit, and 1194you are building a bi-arch or multi-arch binutils in a combined tree. 1195On mips-linux, this will build a tri-arch compiler (ABI o32/n32/64), 1196defaulted to o32. 1197Currently, this option only affects sparc-linux, powerpc-linux, x86-linux, 1198mips-linux and s390-linux. 1199</p> 1200</dd> 1201<dt><code>--enable-secureplt</code></dt> 1202<dd><p>This option enables <samp>-msecure-plt</samp> by default for powerpc-linux. 1203See “RS/6000 and PowerPC Options” in the main manual 1204</p> 1205</dd> 1206<dt><code>--enable-cld</code></dt> 1207<dd><p>This option enables <samp>-mcld</samp> by default for 32-bit x86 targets. 1208See “i386 and x86-64 Options” in the main manual 1209</p> 1210</dd> 1211<dt><code>--enable-win32-registry</code></dt> 1212<dt><code>--enable-win32-registry=<var>key</var></code></dt> 1213<dt><code>--disable-win32-registry</code></dt> 1214<dd><p>The <samp>--enable-win32-registry</samp> option enables Microsoft Windows-hosted GCC 1215to look up installations paths in the registry using the following key: 1216</p> 1217<div class="smallexample"> 1218<pre class="smallexample"><code>HKEY_LOCAL_MACHINE\SOFTWARE\Free Software Foundation\<var>key</var></code> 1219</pre></div> 1220 1221<p><var>key</var> defaults to GCC version number, and can be overridden by the 1222<samp>--enable-win32-registry=<var>key</var></samp> option. Vendors and distributors 1223who use custom installers are encouraged to provide a different key, 1224perhaps one comprised of vendor name and GCC version number, to 1225avoid conflict with existing installations. This feature is enabled 1226by default, and can be disabled by <samp>--disable-win32-registry</samp> 1227option. This option has no effect on the other hosts. 1228</p> 1229</dd> 1230<dt><code>--nfp</code></dt> 1231<dd><p>Specify that the machine does not have a floating point unit. This 1232option only applies to ‘<samp>m68k-sun-sunos<var>n</var></samp>’. On any other 1233system, <samp>--nfp</samp> has no effect. 1234</p> 1235</dd> 1236<dt><code>--enable-werror</code></dt> 1237<dt><code>--disable-werror</code></dt> 1238<dt><code>--enable-werror=yes</code></dt> 1239<dt><code>--enable-werror=no</code></dt> 1240<dd><p>When you specify this option, it controls whether certain files in the 1241compiler are built with <samp>-Werror</samp> in bootstrap stage2 and later. 1242If you don’t specify it, <samp>-Werror</samp> is turned on for the main 1243development trunk. However it defaults to off for release branches and 1244final releases. The specific files which get <samp>-Werror</samp> are 1245controlled by the Makefiles. 1246</p> 1247</dd> 1248<dt><code>--enable-checking</code></dt> 1249<dt><code>--enable-checking=<var>list</var></code></dt> 1250<dd><p>When you specify this option, the compiler is built to perform internal 1251consistency checks of the requested complexity. This does not change the 1252generated code, but adds error checking within the compiler. This will 1253slow down the compiler and may only work properly if you are building 1254the compiler with GCC. This is ‘<samp>yes</samp>’ by default when building 1255from SVN or snapshots, but ‘<samp>release</samp>’ for releases. The default 1256for building the stage1 compiler is ‘<samp>yes</samp>’. More control 1257over the checks may be had by specifying <var>list</var>. The categories of 1258checks available are ‘<samp>yes</samp>’ (most common checks 1259‘<samp>assert,misc,tree,gc,rtlflag,runtime</samp>’), ‘<samp>no</samp>’ (no checks at 1260all), ‘<samp>all</samp>’ (all but ‘<samp>valgrind</samp>’), ‘<samp>release</samp>’ (cheapest 1261checks ‘<samp>assert,runtime</samp>’) or ‘<samp>none</samp>’ (same as ‘<samp>no</samp>’). 1262Individual checks can be enabled with these flags ‘<samp>assert</samp>’, 1263‘<samp>df</samp>’, ‘<samp>fold</samp>’, ‘<samp>gc</samp>’, ‘<samp>gcac</samp>’ ‘<samp>misc</samp>’, ‘<samp>rtl</samp>’, 1264‘<samp>rtlflag</samp>’, ‘<samp>runtime</samp>’, ‘<samp>tree</samp>’, and ‘<samp>valgrind</samp>’. 1265</p> 1266<p>The ‘<samp>valgrind</samp>’ check requires the external <code>valgrind</code> 1267simulator, available from <a href="http://valgrind.org/">http://valgrind.org/</a>. The 1268‘<samp>df</samp>’, ‘<samp>rtl</samp>’, ‘<samp>gcac</samp>’ and ‘<samp>valgrind</samp>’ checks are very expensive. 1269To disable all checking, ‘<samp>--disable-checking</samp>’ or 1270‘<samp>--enable-checking=none</samp>’ must be explicitly requested. Disabling 1271assertions will make the compiler and runtime slightly faster but 1272increase the risk of undetected internal errors causing wrong code to be 1273generated. 1274</p> 1275</dd> 1276<dt><code>--disable-stage1-checking</code></dt> 1277<dt><code>--enable-stage1-checking</code></dt> 1278<dt><code>--enable-stage1-checking=<var>list</var></code></dt> 1279<dd><p>If no <samp>--enable-checking</samp> option is specified the stage1 1280compiler will be built with ‘<samp>yes</samp>’ checking enabled, otherwise 1281the stage1 checking flags are the same as specified by 1282<samp>--enable-checking</samp>. To build the stage1 compiler with 1283different checking options use <samp>--enable-stage1-checking</samp>. 1284The list of checking options is the same as for <samp>--enable-checking</samp>. 1285If your system is too slow or too small to bootstrap a released compiler 1286with checking for stage1 enabled, you can use ‘<samp>--disable-stage1-checking</samp>’ 1287to disable checking for the stage1 compiler. 1288</p> 1289</dd> 1290<dt><code>--enable-coverage</code></dt> 1291<dt><code>--enable-coverage=<var>level</var></code></dt> 1292<dd><p>With this option, the compiler is built to collect self coverage 1293information, every time it is run. This is for internal development 1294purposes, and only works when the compiler is being built with gcc. The 1295<var>level</var> argument controls whether the compiler is built optimized or 1296not, values are ‘<samp>opt</samp>’ and ‘<samp>noopt</samp>’. For coverage analysis you 1297want to disable optimization, for performance analysis you want to 1298enable optimization. When coverage is enabled, the default level is 1299without optimization. 1300</p> 1301</dd> 1302<dt><code>--enable-gather-detailed-mem-stats</code></dt> 1303<dd><p>When this option is specified more detailed information on memory 1304allocation is gathered. This information is printed when using 1305<samp>-fmem-report</samp>. 1306</p> 1307</dd> 1308<dt><code>--enable-nls</code></dt> 1309<dt><code>--disable-nls</code></dt> 1310<dd><p>The <samp>--enable-nls</samp> option enables Native Language Support (NLS), 1311which lets GCC output diagnostics in languages other than American 1312English. Native Language Support is enabled by default if not doing a 1313canadian cross build. The <samp>--disable-nls</samp> option disables NLS. 1314</p> 1315</dd> 1316<dt><code>--with-included-gettext</code></dt> 1317<dd><p>If NLS is enabled, the <samp>--with-included-gettext</samp> option causes the build 1318procedure to prefer its copy of GNU <code>gettext</code>. 1319</p> 1320</dd> 1321<dt><code>--with-catgets</code></dt> 1322<dd><p>If NLS is enabled, and if the host lacks <code>gettext</code> but has the 1323inferior <code>catgets</code> interface, the GCC build procedure normally 1324ignores <code>catgets</code> and instead uses GCC’s copy of the GNU 1325<code>gettext</code> library. The <samp>--with-catgets</samp> option causes the 1326build procedure to use the host’s <code>catgets</code> in this situation. 1327</p> 1328</dd> 1329<dt><code>--with-libiconv-prefix=<var>dir</var></code></dt> 1330<dd><p>Search for libiconv header files in <samp><var>dir</var>/include</samp> and 1331libiconv library files in <samp><var>dir</var>/lib</samp>. 1332</p> 1333</dd> 1334<dt><code>--enable-obsolete</code></dt> 1335<dd><p>Enable configuration for an obsoleted system. If you attempt to 1336configure GCC for a system (build, host, or target) which has been 1337obsoleted, and you do not specify this flag, configure will halt with an 1338error message. 1339</p> 1340<p>All support for systems which have been obsoleted in one release of GCC 1341is removed entirely in the next major release, unless someone steps 1342forward to maintain the port. 1343</p> 1344</dd> 1345<dt><code>--enable-decimal-float</code></dt> 1346<dt><code>--enable-decimal-float=yes</code></dt> 1347<dt><code>--enable-decimal-float=no</code></dt> 1348<dt><code>--enable-decimal-float=bid</code></dt> 1349<dt><code>--enable-decimal-float=dpd</code></dt> 1350<dt><code>--disable-decimal-float</code></dt> 1351<dd><p>Enable (or disable) support for the C decimal floating point extension 1352that is in the IEEE 754-2008 standard. This is enabled by default only 1353on PowerPC, i386, and x86_64 GNU/Linux systems. Other systems may also 1354support it, but require the user to specifically enable it. You can 1355optionally control which decimal floating point format is used (either 1356‘<samp>bid</samp>’ or ‘<samp>dpd</samp>’). The ‘<samp>bid</samp>’ (binary integer decimal) 1357format is default on i386 and x86_64 systems, and the ‘<samp>dpd</samp>’ 1358(densely packed decimal) format is default on PowerPC systems. 1359</p> 1360</dd> 1361<dt><code>--enable-fixed-point</code></dt> 1362<dt><code>--disable-fixed-point</code></dt> 1363<dd><p>Enable (or disable) support for C fixed-point arithmetic. 1364This option is enabled by default for some targets (such as MIPS) which 1365have hardware-support for fixed-point operations. On other targets, you 1366may enable this option manually. 1367</p> 1368</dd> 1369<dt><code>--with-long-double-128</code></dt> 1370<dd><p>Specify if <code>long double</code> type should be 128-bit by default on selected 1371GNU/Linux architectures. If using <code>--without-long-double-128</code>, 1372<code>long double</code> will be by default 64-bit, the same as <code>double</code> type. 1373When neither of these configure options are used, the default will be 1374128-bit <code>long double</code> when built against GNU C Library 2.4 and later, 137564-bit <code>long double</code> otherwise. 1376</p> 1377</dd> 1378<dt><code>--with-gmp=<var>pathname</var></code></dt> 1379<dt><code>--with-gmp-include=<var>pathname</var></code></dt> 1380<dt><code>--with-gmp-lib=<var>pathname</var></code></dt> 1381<dt><code>--with-mpfr=<var>pathname</var></code></dt> 1382<dt><code>--with-mpfr-include=<var>pathname</var></code></dt> 1383<dt><code>--with-mpfr-lib=<var>pathname</var></code></dt> 1384<dt><code>--with-mpc=<var>pathname</var></code></dt> 1385<dt><code>--with-mpc-include=<var>pathname</var></code></dt> 1386<dt><code>--with-mpc-lib=<var>pathname</var></code></dt> 1387<dd><p>If you want to build GCC but do not have the GMP library, the MPFR 1388library and/or the MPC library installed in a standard location and 1389do not have their sources present in the GCC source tree then you 1390can explicitly specify the directory where they are installed 1391(‘<samp>--with-gmp=<var>gmpinstalldir</var></samp>’, 1392‘<samp>--with-mpfr=<var>mpfrinstalldir</var></samp>’, 1393‘<samp>--with-mpc=<var>mpcinstalldir</var></samp>’). The 1394<samp>--with-gmp=<var>gmpinstalldir</var></samp> option is shorthand for 1395<samp>--with-gmp-lib=<var>gmpinstalldir</var>/lib</samp> and 1396<samp>--with-gmp-include=<var>gmpinstalldir</var>/include</samp>. Likewise the 1397<samp>--with-mpfr=<var>mpfrinstalldir</var></samp> option is shorthand for 1398<samp>--with-mpfr-lib=<var>mpfrinstalldir</var>/lib</samp> and 1399<samp>--with-mpfr-include=<var>mpfrinstalldir</var>/include</samp>, also the 1400<samp>--with-mpc=<var>mpcinstalldir</var></samp> option is shorthand for 1401<samp>--with-mpc-lib=<var>mpcinstalldir</var>/lib</samp> and 1402<samp>--with-mpc-include=<var>mpcinstalldir</var>/include</samp>. If these 1403shorthand assumptions are not correct, you can use the explicit 1404include and lib options directly. You might also need to ensure the 1405shared libraries can be found by the dynamic linker when building and 1406using GCC, for example by setting the runtime shared library path 1407variable (<code>LD_LIBRARY_PATH</code> on GNU/Linux and Solaris systems). 1408</p> 1409<p>These flags are applicable to the host platform only. When building 1410a cross compiler, they will not be used to configure target libraries. 1411</p> 1412</dd> 1413<dt><code>--with-isl=<var>pathname</var></code></dt> 1414<dt><code>--with-isl-include=<var>pathname</var></code></dt> 1415<dt><code>--with-isl-lib=<var>pathname</var></code></dt> 1416<dd><p>If you do not have the ISL library installed in a standard location and you 1417want to build GCC, you can explicitly specify the directory where it is 1418installed (‘<samp>--with-isl=<var>islinstalldir</var></samp>’). The 1419<samp>--with-isl=<var>islinstalldir</var></samp> option is shorthand for 1420<samp>--with-isl-lib=<var>islinstalldir</var>/lib</samp> and 1421<samp>--with-isl-include=<var>islinstalldir</var>/include</samp>. If this 1422shorthand assumption is not correct, you can use the explicit 1423include and lib options directly. 1424</p> 1425<p>These flags are applicable to the host platform only. When building 1426a cross compiler, they will not be used to configure target libraries. 1427</p> 1428</dd> 1429<dt><code>--with-host-libstdcxx=<var>linker-args</var></code></dt> 1430<dd><p>If you are linking with a static copy of PPL, you can use this option 1431to specify how the linker should find the standard C++ library used 1432internally by PPL. Typical values of <var>linker-args</var> might be 1433‘<samp>-lstdc++</samp>’ or ‘<samp>-Wl,-Bstatic,-lstdc++,-Bdynamic -lm</samp>’. If you are 1434linking with a shared copy of PPL, you probably do not need this 1435option; shared library dependencies will cause the linker to search 1436for the standard C++ library automatically. 1437</p> 1438</dd> 1439<dt><code>--with-stage1-ldflags=<var>flags</var></code></dt> 1440<dd><p>This option may be used to set linker flags to be used when linking 1441stage 1 of GCC. These are also used when linking GCC if configured with 1442<samp>--disable-bootstrap</samp>. By default no special flags are used. 1443</p> 1444</dd> 1445<dt><code>--with-stage1-libs=<var>libs</var></code></dt> 1446<dd><p>This option may be used to set libraries to be used when linking stage 1 1447of GCC. These are also used when linking GCC if configured with 1448<samp>--disable-bootstrap</samp>. The default is the argument to 1449<samp>--with-host-libstdcxx</samp>, if specified. 1450</p> 1451</dd> 1452<dt><code>--with-boot-ldflags=<var>flags</var></code></dt> 1453<dd><p>This option may be used to set linker flags to be used when linking 1454stage 2 and later when bootstrapping GCC. If neither –with-boot-libs 1455nor –with-host-libstdcxx is set to a value, then the default is 1456‘<samp>-static-libstdc++ -static-libgcc</samp>’. 1457</p> 1458</dd> 1459<dt><code>--with-boot-libs=<var>libs</var></code></dt> 1460<dd><p>This option may be used to set libraries to be used when linking stage 2 1461and later when bootstrapping GCC. The default is the argument to 1462<samp>--with-host-libstdcxx</samp>, if specified. 1463</p> 1464</dd> 1465<dt><code>--with-debug-prefix-map=<var>map</var></code></dt> 1466<dd><p>Convert source directory names using <samp>-fdebug-prefix-map</samp> when 1467building runtime libraries. ‘<samp><var>map</var></samp>’ is a space-separated 1468list of maps of the form ‘<samp><var>old</var>=<var>new</var></samp>’. 1469</p> 1470</dd> 1471<dt><code>--enable-linker-build-id</code></dt> 1472<dd><p>Tells GCC to pass <samp>--build-id</samp> option to the linker for all final 1473links (links performed without the <samp>-r</samp> or <samp>--relocatable</samp> 1474option), if the linker supports it. If you specify 1475<samp>--enable-linker-build-id</samp>, but your linker does not 1476support <samp>--build-id</samp> option, a warning is issued and the 1477<samp>--enable-linker-build-id</samp> option is ignored. The default is off. 1478</p> 1479</dd> 1480<dt><code>--with-linker-hash-style=<var>choice</var></code></dt> 1481<dd><p>Tells GCC to pass <samp>--hash-style=<var>choice</var></samp> option to the 1482linker for all final links. <var>choice</var> can be one of 1483‘<samp>sysv</samp>’, ‘<samp>gnu</samp>’, and ‘<samp>both</samp>’ where ‘<samp>sysv</samp>’ is the default. 1484</p> 1485</dd> 1486<dt><code>--enable-gnu-unique-object</code></dt> 1487<dt><code>--disable-gnu-unique-object</code></dt> 1488<dd><p>Tells GCC to use the gnu_unique_object relocation for C++ template 1489static data members and inline function local statics. Enabled by 1490default for a toolchain with an assembler that accepts it and 1491GLIBC 2.11 or above, otherwise disabled. 1492</p> 1493</dd> 1494<dt><code>--with-diagnostics-color=<var>choice</var></code></dt> 1495<dd><p>Tells GCC to use <var>choice</var> as the default for <samp>-fdiagnostics-color=</samp> 1496option (if not used explicitly on the command line). <var>choice</var> 1497can be one of ‘<samp>never</samp>’, ‘<samp>auto</samp>’, ‘<samp>always</samp>’, and ‘<samp>auto-if-env</samp>’ 1498where ‘<samp>auto</samp>’ is the default. ‘<samp>auto-if-env</samp>’ means that 1499<samp>-fdiagnostics-color=auto</samp> will be the default if <code>GCC_COLORS</code> 1500is present and non-empty in the environment, and 1501<samp>-fdiagnostics-color=never</samp> otherwise. 1502</p> 1503</dd> 1504<dt><code>--enable-lto</code></dt> 1505<dt><code>--disable-lto</code></dt> 1506<dd><p>Enable support for link-time optimization (LTO). This is enabled by 1507default, and may be disabled using <samp>--disable-lto</samp>. 1508</p> 1509</dd> 1510<dt><code>--enable-linker-plugin-configure-flags=FLAGS</code></dt> 1511<dt><code>--enable-linker-plugin-flags=FLAGS</code></dt> 1512<dd><p>By default, linker plugins (such as the LTO plugin) are built for the 1513host system architecture. For the case that the linker has a 1514different (but run-time compatible) architecture, these flags can be 1515specified to build plugins that are compatible to the linker. For 1516example, if you are building GCC for a 64-bit x86_64 1517(‘<samp>x86_64-unknown-linux-gnu</samp>’) host system, but have a 32-bit x86 1518GNU/Linux (‘<samp>i686-pc-linux-gnu</samp>’) linker executable (which is 1519executable on the former system), you can configure GCC as follows for 1520getting compatible linker plugins: 1521</p> 1522<div class="smallexample"> 1523<pre class="smallexample">% <var>srcdir</var>/configure \ 1524 --host=x86_64-unknown-linux-gnu \ 1525 --enable-linker-plugin-configure-flags=--host=i686-pc-linux-gnu \ 1526 --enable-linker-plugin-flags='CC=gcc\ -m32\ -Wl,-rpath,[...]/i686-pc-linux-gnu/lib' 1527</pre></div> 1528 1529</dd> 1530<dt><code>--with-plugin-ld=<var>pathname</var></code></dt> 1531<dd><p>Enable an alternate linker to be used at link-time optimization (LTO) 1532link time when <samp>-fuse-linker-plugin</samp> is enabled. 1533This linker should have plugin support such as gold starting with 1534version 2.20 or GNU ld starting with version 2.21. 1535See <samp>-fuse-linker-plugin</samp> for details. 1536</p> 1537</dd> 1538<dt><code>--enable-canonical-system-headers</code></dt> 1539<dt><code>--disable-canonical-system-headers</code></dt> 1540<dd><p>Enable system header path canonicalization for <samp>libcpp</samp>. This can 1541produce shorter header file paths in diagnostics and dependency output 1542files, but these changed header paths may conflict with some compilation 1543environments. Enabled by default, and may be disabled using 1544<samp>--disable-canonical-system-headers</samp>. 1545</p> 1546</dd> 1547<dt><code>--with-glibc-version=<var>major</var>.<var>minor</var></code></dt> 1548<dd><p>Tell GCC that when the GNU C Library (glibc) is used on the target it 1549will be version <var>major</var>.<var>minor</var> or later. Normally this can 1550be detected from the C library’s header files, but this option may be 1551needed when bootstrapping a cross toolchain without the header files 1552available for building the initial bootstrap compiler. 1553</p> 1554<p>If GCC is configured with some multilibs that use glibc and some that 1555do not, this option applies only to the multilibs that use glibc. 1556However, such configurations may not work well as not all the relevant 1557configuration in GCC is on a per-multilib basis. 1558</p> 1559</dd> 1560<dt><code>--enable-as-accelerator-for=<var>target</var></code></dt> 1561<dd><p>Build as offload target compiler. Specify offload host triple by <var>target</var>. 1562</p> 1563</dd> 1564<dt><code>--enable-offload-targets=<var>target1</var>[=<var>path1</var>],…,<var>targetN</var>[=<var>pathN</var>]</code></dt> 1565<dd><p>Enable offloading to targets <var>target1</var>, …, <var>targetN</var>. 1566Offload compilers are expected to be already installed. Default search 1567path for them is <samp><var>exec-prefix</var></samp>, but it can be changed by 1568specifying paths <var>path1</var>, …, <var>pathN</var>. 1569</p> 1570<div class="smallexample"> 1571<pre class="smallexample">% <var>srcdir</var>/configure \ 1572 --enable-offload-target=i686-unknown-linux-gnu=/path/to/i686/compiler,x86_64-pc-linux-gnu 1573</pre></div> 1574</dd> 1575</dl> 1576 1577<a name="Cross_002dCompiler_002dSpecific-Options"></a> 1578<h4 class="subheading">Cross-Compiler-Specific Options</h4> 1579<p>The following options only apply to building cross compilers. 1580</p> 1581<dl compact="compact"> 1582<dt><code>--with-sysroot</code></dt> 1583<dt><code>--with-sysroot=<var>dir</var></code></dt> 1584<dd><p>Tells GCC to consider <var>dir</var> as the root of a tree that contains 1585(a subset of) the root filesystem of the target operating system. 1586Target system headers, libraries and run-time object files will be 1587searched for in there. More specifically, this acts as if 1588<samp>--sysroot=<var>dir</var></samp> was added to the default options of the built 1589compiler. The specified directory is not copied into the 1590install tree, unlike the options <samp>--with-headers</samp> and 1591<samp>--with-libs</samp> that this option obsoletes. The default value, 1592in case <samp>--with-sysroot</samp> is not given an argument, is 1593<samp>${gcc_tooldir}/sys-root</samp>. If the specified directory is a 1594subdirectory of <samp>${exec_prefix}</samp>, then it will be found relative to 1595the GCC binaries if the installation tree is moved. 1596</p> 1597<p>This option affects the system root for the compiler used to build 1598target libraries (which runs on the build system) and the compiler newly 1599installed with <code>make install</code>; it does not affect the compiler which is 1600used to build GCC itself. 1601</p> 1602<p>If you specify the <samp>--with-native-system-header-dir=<var>dirname</var></samp> 1603option then the compiler will search that directory within <var>dirname</var> for 1604native system headers rather than the default <samp>/usr/include</samp>. 1605</p> 1606</dd> 1607<dt><code>--with-build-sysroot</code></dt> 1608<dt><code>--with-build-sysroot=<var>dir</var></code></dt> 1609<dd><p>Tells GCC to consider <var>dir</var> as the system root (see 1610<samp>--with-sysroot</samp>) while building target libraries, instead of 1611the directory specified with <samp>--with-sysroot</samp>. This option is 1612only useful when you are already using <samp>--with-sysroot</samp>. You 1613can use <samp>--with-build-sysroot</samp> when you are configuring with 1614<samp>--prefix</samp> set to a directory that is different from the one in 1615which you are installing GCC and your target libraries. 1616</p> 1617<p>This option affects the system root for the compiler used to build 1618target libraries (which runs on the build system); it does not affect 1619the compiler which is used to build GCC itself. 1620</p> 1621<p>If you specify the <samp>--with-native-system-header-dir=<var>dirname</var></samp> 1622option then the compiler will search that directory within <var>dirname</var> for 1623native system headers rather than the default <samp>/usr/include</samp>. 1624</p> 1625</dd> 1626<dt><code>--with-headers</code></dt> 1627<dt><code>--with-headers=<var>dir</var></code></dt> 1628<dd><p>Deprecated in favor of <samp>--with-sysroot</samp>. 1629Specifies that target headers are available when building a cross compiler. 1630The <var>dir</var> argument specifies a directory which has the target include 1631files. These include files will be copied into the <samp>gcc</samp> install 1632directory. <em>This option with the <var>dir</var> argument is required</em> when 1633building a cross compiler, if <samp><var>prefix</var>/<var>target</var>/sys-include</samp> 1634doesn’t pre-exist. If <samp><var>prefix</var>/<var>target</var>/sys-include</samp> does 1635pre-exist, the <var>dir</var> argument may be omitted. <code>fixincludes</code> 1636will be run on these files to make them compatible with GCC. 1637</p> 1638</dd> 1639<dt><code>--without-headers</code></dt> 1640<dd><p>Tells GCC not use any target headers from a libc when building a cross 1641compiler. When crossing to GNU/Linux, you need the headers so GCC 1642can build the exception handling for libgcc. 1643</p> 1644</dd> 1645<dt><code>--with-libs</code></dt> 1646<dt><code>--with-libs="<var>dir1</var> <var>dir2</var> … <var>dirN</var>"</code></dt> 1647<dd><p>Deprecated in favor of <samp>--with-sysroot</samp>. 1648Specifies a list of directories which contain the target runtime 1649libraries. These libraries will be copied into the <samp>gcc</samp> install 1650directory. If the directory list is omitted, this option has no 1651effect. 1652</p> 1653</dd> 1654<dt><code>--with-newlib</code></dt> 1655<dd><p>Specifies that ‘<samp>newlib</samp>’ is 1656being used as the target C library. This causes <code>__eprintf</code> to be 1657omitted from <samp>libgcc.a</samp> on the assumption that it will be provided by 1658‘<samp>newlib</samp>’. 1659</p> 1660</dd> 1661<dt><code>--with-avrlibc</code></dt> 1662<dd><p>Specifies that ‘<samp>AVR-Libc</samp>’ is 1663being used as the target C library. This causes float support 1664functions like <code>__addsf3</code> to be omitted from <samp>libgcc.a</samp> on 1665the assumption that it will be provided by <samp>libm.a</samp>. For more 1666technical details, cf. <a href="http://gcc.gnu.org/PR54461">PR54461</a>. 1667This option is only supported for the AVR target. It is not supported for 1668RTEMS configurations, which currently use newlib. The option is 1669supported since version 4.7.2 and is the default in 4.8.0 and newer. 1670</p> 1671</dd> 1672<dt><code>--with-nds32-lib=<var>library</var></code></dt> 1673<dd><p>Specifies that <var>library</var> setting is used for building <samp>libgcc.a</samp>. 1674Currently, the valid <var>library</var> is ‘<samp>newlib</samp>’ or ‘<samp>mculib</samp>’. 1675This option is only supported for the NDS32 target. 1676</p> 1677</dd> 1678<dt><code>--with-build-time-tools=<var>dir</var></code></dt> 1679<dd><p>Specifies where to find the set of target tools (assembler, linker, etc.) 1680that will be used while building GCC itself. This option can be useful 1681if the directory layouts are different between the system you are building 1682GCC on, and the system where you will deploy it. 1683</p> 1684<p>For example, on an ‘<samp>ia64-hp-hpux</samp>’ system, you may have the GNU 1685assembler and linker in <samp>/usr/bin</samp>, and the native tools in a 1686different path, and build a toolchain that expects to find the 1687native tools in <samp>/usr/bin</samp>. 1688</p> 1689<p>When you use this option, you should ensure that <var>dir</var> includes 1690<code>ar</code>, <code>as</code>, <code>ld</code>, <code>nm</code>, 1691<code>ranlib</code> and <code>strip</code> if necessary, and possibly 1692<code>objdump</code>. Otherwise, GCC may use an inconsistent set of 1693tools. 1694</p></dd> 1695</dl> 1696 1697<a name="Overriding-configure-test-results"></a> 1698<h4 class="subsubheading">Overriding <code>configure</code> test results</h4> 1699 1700<p>Sometimes, it might be necessary to override the result of some 1701<code>configure</code> test, for example in order to ease porting to a new 1702system or work around a bug in a test. The toplevel <code>configure</code> 1703script provides three variables for this: 1704</p> 1705<dl compact="compact"> 1706<dt><code>build_configargs</code></dt> 1707<dd><a name="index-build_005fconfigargs"></a> 1708<p>The contents of this variable is passed to all build <code>configure</code> 1709scripts. 1710</p> 1711</dd> 1712<dt><code>host_configargs</code></dt> 1713<dd><a name="index-host_005fconfigargs"></a> 1714<p>The contents of this variable is passed to all host <code>configure</code> 1715scripts. 1716</p> 1717</dd> 1718<dt><code>target_configargs</code></dt> 1719<dd><a name="index-target_005fconfigargs"></a> 1720<p>The contents of this variable is passed to all target <code>configure</code> 1721scripts. 1722</p> 1723</dd> 1724</dl> 1725 1726<p>In order to avoid shell and <code>make</code> quoting issues for complex 1727overrides, you can pass a setting for <code>CONFIG_SITE</code> and set 1728variables in the site file. 1729</p> 1730<a name="Java_002dSpecific-Options"></a> 1731<h4 class="subheading">Java-Specific Options</h4> 1732 1733<p>The following option applies to the build of the Java front end. 1734</p> 1735<dl compact="compact"> 1736<dt><code>--disable-libgcj</code></dt> 1737<dd><p>Specify that the run-time libraries 1738used by GCJ should not be built. This is useful in case you intend 1739to use GCJ with some other run-time, or you’re going to install it 1740separately, or it just happens not to build on your particular 1741machine. In general, if the Java front end is enabled, the GCJ 1742libraries will be enabled too, unless they’re known to not work on 1743the target platform. If GCJ is enabled but ‘<samp>libgcj</samp>’ isn’t built, you 1744may need to port it; in this case, before modifying the top-level 1745<samp>configure.in</samp> so that ‘<samp>libgcj</samp>’ is enabled by default on this platform, 1746you may use <samp>--enable-libgcj</samp> to override the default. 1747</p> 1748</dd> 1749</dl> 1750 1751<p>The following options apply to building ‘<samp>libgcj</samp>’. 1752</p> 1753<a name="General-Options"></a> 1754<h4 class="subsubheading">General Options</h4> 1755 1756<dl compact="compact"> 1757<dt><code>--enable-java-maintainer-mode</code></dt> 1758<dd><p>By default the ‘<samp>libjava</samp>’ build will not attempt to compile the 1759<samp>.java</samp> source files to <samp>.class</samp>. Instead, it will use the 1760<samp>.class</samp> files from the source tree. If you use this option you 1761must have executables named <code>ecj1</code> and <code>gjavah</code> in your path 1762for use by the build. You must use this option if you intend to 1763modify any <samp>.java</samp> files in <samp>libjava</samp>. 1764</p> 1765</dd> 1766<dt><code>--with-java-home=<var>dirname</var></code></dt> 1767<dd><p>This ‘<samp>libjava</samp>’ option overrides the default value of the 1768‘<samp>java.home</samp>’ system property. It is also used to set 1769‘<samp>sun.boot.class.path</samp>’ to <samp><var>dirname</var>/lib/rt.jar</samp>. By 1770default ‘<samp>java.home</samp>’ is set to <samp><var>prefix</var></samp> and 1771‘<samp>sun.boot.class.path</samp>’ to 1772<samp><var>datadir</var>/java/libgcj-<var>version</var>.jar</samp>. 1773</p> 1774</dd> 1775<dt><code>--with-ecj-jar=<var>filename</var></code></dt> 1776<dd><p>This option can be used to specify the location of an external jar 1777file containing the Eclipse Java compiler. A specially modified 1778version of this compiler is used by <code>gcj</code> to parse 1779<samp>.java</samp> source files. If this option is given, the 1780‘<samp>libjava</samp>’ build will create and install an <samp>ecj1</samp> executable 1781which uses this jar file at runtime. 1782</p> 1783<p>If this option is not given, but an <samp>ecj.jar</samp> file is found in 1784the topmost source tree at configure time, then the ‘<samp>libgcj</samp>’ 1785build will create and install <samp>ecj1</samp>, and will also install the 1786discovered <samp>ecj.jar</samp> into a suitable place in the install tree. 1787</p> 1788<p>If <samp>ecj1</samp> is not installed, then the user will have to supply one 1789on his path in order for <code>gcj</code> to properly parse <samp>.java</samp> 1790source files. A suitable jar is available from 1791<a href="ftp://sourceware.org/pub/java/">ftp://sourceware.org/pub/java/</a>. 1792</p> 1793</dd> 1794<dt><code>--disable-getenv-properties</code></dt> 1795<dd><p>Don’t set system properties from <code>GCJ_PROPERTIES</code>. 1796</p> 1797</dd> 1798<dt><code>--enable-hash-synchronization</code></dt> 1799<dd><p>Use a global hash table for monitor locks. Ordinarily, 1800‘<samp>libgcj</samp>’’s ‘<samp>configure</samp>’ script automatically makes 1801the correct choice for this option for your platform. Only use 1802this if you know you need the library to be configured differently. 1803</p> 1804</dd> 1805<dt><code>--enable-interpreter</code></dt> 1806<dd><p>Enable the Java interpreter. The interpreter is automatically 1807enabled by default on all platforms that support it. This option 1808is really only useful if you want to disable the interpreter 1809(using <samp>--disable-interpreter</samp>). 1810</p> 1811</dd> 1812<dt><code>--disable-java-net</code></dt> 1813<dd><p>Disable java.net. This disables the native part of java.net only, 1814using non-functional stubs for native method implementations. 1815</p> 1816</dd> 1817<dt><code>--disable-jvmpi</code></dt> 1818<dd><p>Disable JVMPI support. 1819</p> 1820</dd> 1821<dt><code>--disable-libgcj-bc</code></dt> 1822<dd><p>Disable BC ABI compilation of certain parts of libgcj. By default, 1823some portions of libgcj are compiled with <samp>-findirect-dispatch</samp> 1824and <samp>-fno-indirect-classes</samp>, allowing them to be overridden at 1825run-time. 1826</p> 1827<p>If <samp>--disable-libgcj-bc</samp> is specified, libgcj is built without 1828these options. This allows the compile-time linker to resolve 1829dependencies when statically linking to libgcj. However it makes it 1830impossible to override the affected portions of libgcj at run-time. 1831</p> 1832</dd> 1833<dt><code>--enable-reduced-reflection</code></dt> 1834<dd><p>Build most of libgcj with <samp>-freduced-reflection</samp>. This reduces 1835the size of libgcj at the expense of not being able to do accurate 1836reflection on the classes it contains. This option is safe if you 1837know that code using libgcj will never use reflection on the standard 1838runtime classes in libgcj (including using serialization, RMI or CORBA). 1839</p> 1840</dd> 1841<dt><code>--with-ecos</code></dt> 1842<dd><p>Enable runtime eCos target support. 1843</p> 1844</dd> 1845<dt><code>--without-libffi</code></dt> 1846<dd><p>Don’t use ‘<samp>libffi</samp>’. This will disable the interpreter and JNI 1847support as well, as these require ‘<samp>libffi</samp>’ to work. 1848</p> 1849</dd> 1850<dt><code>--enable-libgcj-debug</code></dt> 1851<dd><p>Enable runtime debugging code. 1852</p> 1853</dd> 1854<dt><code>--enable-libgcj-multifile</code></dt> 1855<dd><p>If specified, causes all <samp>.java</samp> source files to be 1856compiled into <samp>.class</samp> files in one invocation of 1857‘<samp>gcj</samp>’. This can speed up build time, but is more 1858resource-intensive. If this option is unspecified or 1859disabled, ‘<samp>gcj</samp>’ is invoked once for each <samp>.java</samp> 1860file to compile into a <samp>.class</samp> file. 1861</p> 1862</dd> 1863<dt><code>--with-libiconv-prefix=DIR</code></dt> 1864<dd><p>Search for libiconv in <samp>DIR/include</samp> and <samp>DIR/lib</samp>. 1865</p> 1866</dd> 1867<dt><code>--with-system-zlib</code></dt> 1868<dd><p>Use installed ‘<samp>zlib</samp>’ rather than that included with GCC. 1869</p> 1870</dd> 1871<dt><code>--with-win32-nlsapi=ansi, unicows or unicode</code></dt> 1872<dd><p>Indicates how MinGW ‘<samp>libgcj</samp>’ translates between UNICODE 1873characters and the Win32 API. 1874</p> 1875</dd> 1876<dt><code>--enable-java-home</code></dt> 1877<dd><p>If enabled, this creates a JPackage compatible SDK environment during install. 1878Note that if –enable-java-home is used, –with-arch-directory=ARCH must also 1879be specified. 1880</p> 1881</dd> 1882<dt><code>--with-arch-directory=ARCH</code></dt> 1883<dd><p>Specifies the name to use for the <samp>jre/lib/ARCH</samp> directory in the SDK 1884environment created when –enable-java-home is passed. Typical names for this 1885directory include i386, amd64, ia64, etc. 1886</p> 1887</dd> 1888<dt><code>--with-os-directory=DIR</code></dt> 1889<dd><p>Specifies the OS directory for the SDK include directory. This is set to auto 1890detect, and is typically ’linux’. 1891</p> 1892</dd> 1893<dt><code>--with-origin-name=NAME</code></dt> 1894<dd><p>Specifies the JPackage origin name. This defaults to the ’gcj’ in 1895java-1.5.0-gcj. 1896</p> 1897</dd> 1898<dt><code>--with-arch-suffix=SUFFIX</code></dt> 1899<dd><p>Specifies the suffix for the sdk directory. Defaults to the empty string. 1900Examples include ’.x86_64’ in ’java-1.5.0-gcj-1.5.0.0.x86_64’. 1901</p> 1902</dd> 1903<dt><code>--with-jvm-root-dir=DIR</code></dt> 1904<dd><p>Specifies where to install the SDK. Default is $(prefix)/lib/jvm. 1905</p> 1906</dd> 1907<dt><code>--with-jvm-jar-dir=DIR</code></dt> 1908<dd><p>Specifies where to install jars. Default is $(prefix)/lib/jvm-exports. 1909</p> 1910</dd> 1911<dt><code>--with-python-dir=DIR</code></dt> 1912<dd><p>Specifies where to install the Python modules used for aot-compile. DIR should 1913not include the prefix used in installation. For example, if the Python modules 1914are to be installed in /usr/lib/python2.5/site-packages, then 1915–with-python-dir=/lib/python2.5/site-packages should be passed. If this is 1916not specified, then the Python modules are installed in $(prefix)/share/python. 1917</p> 1918</dd> 1919<dt><code>--enable-aot-compile-rpm</code></dt> 1920<dd><p>Adds aot-compile-rpm to the list of installed scripts. 1921</p> 1922</dd> 1923<dt><code>--enable-browser-plugin</code></dt> 1924<dd><p>Build the gcjwebplugin web browser plugin. 1925</p> 1926</dd> 1927<dt><code>--enable-static-libjava</code></dt> 1928<dd><p>Build static libraries in libjava. The default is to only build shared 1929libraries. 1930</p> 1931<dl compact="compact"> 1932<dt><code>ansi</code></dt> 1933<dd><p>Use the single-byte <code>char</code> and the Win32 A functions natively, 1934translating to and from UNICODE when using these functions. If 1935unspecified, this is the default. 1936</p> 1937</dd> 1938<dt><code>unicows</code></dt> 1939<dd><p>Use the <code>WCHAR</code> and Win32 W functions natively. Adds 1940<code>-lunicows</code> to <samp>libgcj.spec</samp> to link with ‘<samp>libunicows</samp>’. 1941<samp>unicows.dll</samp> needs to be deployed on Microsoft Windows 9X machines 1942running built executables. <samp>libunicows.a</samp>, an open-source 1943import library around Microsoft’s <code>unicows.dll</code>, is obtained from 1944<a href="http://libunicows.sourceforge.net/">http://libunicows.sourceforge.net/</a>, which also gives details 1945on getting <samp>unicows.dll</samp> from Microsoft. 1946</p> 1947</dd> 1948<dt><code>unicode</code></dt> 1949<dd><p>Use the <code>WCHAR</code> and Win32 W functions natively. Does <em>not</em> 1950add <code>-lunicows</code> to <samp>libgcj.spec</samp>. The built executables will 1951only run on Microsoft Windows NT and above. 1952</p></dd> 1953</dl> 1954</dd> 1955</dl> 1956 1957<a name="AWT_002dSpecific-Options"></a> 1958<h4 class="subsubheading">AWT-Specific Options</h4> 1959 1960<dl compact="compact"> 1961<dt><code>--with-x</code></dt> 1962<dd><p>Use the X Window System. 1963</p> 1964</dd> 1965<dt><code>--enable-java-awt=PEER(S)</code></dt> 1966<dd><p>Specifies the AWT peer library or libraries to build alongside 1967‘<samp>libgcj</samp>’. If this option is unspecified or disabled, AWT 1968will be non-functional. Current valid values are <samp>gtk</samp> and 1969<samp>xlib</samp>. Multiple libraries should be separated by a 1970comma (i.e. <samp>--enable-java-awt=gtk,xlib</samp>). 1971</p> 1972</dd> 1973<dt><code>--enable-gtk-cairo</code></dt> 1974<dd><p>Build the cairo Graphics2D implementation on GTK. 1975</p> 1976</dd> 1977<dt><code>--enable-java-gc=TYPE</code></dt> 1978<dd><p>Choose garbage collector. Defaults to <samp>boehm</samp> if unspecified. 1979</p> 1980</dd> 1981<dt><code>--disable-gtktest</code></dt> 1982<dd><p>Do not try to compile and run a test GTK+ program. 1983</p> 1984</dd> 1985<dt><code>--disable-glibtest</code></dt> 1986<dd><p>Do not try to compile and run a test GLIB program. 1987</p> 1988</dd> 1989<dt><code>--with-libart-prefix=PFX</code></dt> 1990<dd><p>Prefix where libart is installed (optional). 1991</p> 1992</dd> 1993<dt><code>--with-libart-exec-prefix=PFX</code></dt> 1994<dd><p>Exec prefix where libart is installed (optional). 1995</p> 1996</dd> 1997<dt><code>--disable-libarttest</code></dt> 1998<dd><p>Do not try to compile and run a test libart program. 1999</p> 2000</dd> 2001</dl> 2002 2003 2004<hr /> 2005<p> 2006<p><a href="./index.html">Return to the GCC Installation page</a> 2007</p> 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019</body> 2020</html> 2021