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diff --git a/libstdc++-v3/doc/html/configopts.html b/libstdc++-v3/doc/html/configopts.html new file mode 100644 index 0000000..c830a99 --- /dev/null +++ b/libstdc++-v3/doc/html/configopts.html @@ -0,0 +1,342 @@ +<?xml version="1.0" encoding="ISO-8859-1"?> +<!DOCTYPE html + PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" + "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> + +<html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en" lang="en"> +<head> + <meta name="AUTHOR" content="pme@gcc.gnu.org (Phil Edwards)" /> + <meta name="KEYWORDS" content="libstdc++, libstdc++, GCC, g++" /> + <meta name="DESCRIPTION" content="Configuration options for libstdc++." /> + <meta name="GENERATOR" content="vi and eight fingers" /> + <title>libstdc++ configure options</title> +<link rel="StyleSheet" href="lib3styles.css" type="text/css" /> +<link rel="Copyright" href="17_intro/license.html" type="text/html" /> +</head> +<body> + +<h1 class="centered"><a name="top">Interesting <code>configure</code> +options</a></h1> + +<p class="fineprint"><em> + The latest version of this document is always available at + <a href="http://gcc.gnu.org/onlinedocs/libstdc++/configopts.html"> + http://gcc.gnu.org/onlinedocs/libstdc++/configopts.html</a>. +</em></p> + +<p><em> + To the <a href="http://gcc.gnu.org/libstdc++/">libstdc++ homepage</a>. +</em></p> + +<!-- ####################################################### --> +<hr /> +<p>Here are some of the non-obvious options to libstdc++'s configure. + Keep in mind that + <!-- This SECnn should be the "Choosing Package Options" section. --> + <a href="http://www.gnu.org/software/autoconf/manual/autoconf-2.57/html_node/autoconf_131.html#SEC131">they + all have opposite forms as well</a> + (enable/disable and with/without). The defaults are for <strong>current + development sources</strong>, which may be different than those for + released versions. +</p> +<p>The canonical way to find out the configure options that are + available for a given set of libstdc++ sources is to go to the + source directory and then type:<code> ./configure --help</code> +</p> + +<dl> + <dt><code>--enable-multilib </code>[default]</dt> + <dd><p>This is part of the generic multilib support for building cross + compilers. As such, targets like "powerpc-elf" will have + libstdc++ built many different ways: "-msoft-float" + and not, etc. A different libstdc++ will be built for each of + the different multilib versions. This option is on by default. + </p> + </dd> + + <dt><code>--enable-sjlj-exceptions </code></dt> + <dd><p>Forces old, set-jump/long-jump exception handling model. If + at all possible, the new, frame unwinding exception handling routines + should be used instead, as they significantly reduce both + runtime memory usage and executable size. This option can + change the library ABI. + </p> + </dd> + + <dt><code>--enable-version-specific-runtime-libs </code></dt> + <dd><p>Specify that run-time libraries should be installed in the + compiler-specific subdirectory (i.e., + <code>${libdir}/gcc-lib/${target_alias}/${gcc_version}</code>) + instead of <code>${libdir}</code>. This option is useful if you + intend to use several versions of gcc in parallel. In addition, + libstdc++'s include files will be installed in + <code>${libdir}/gcc-lib/${target_alias}/${gcc_version}/include/g++</code>, + unless you also specify + <code>--with-gxx-include-dir=<em>dirname</em></code> during configuration. + </p> + </dd> + + <dt><code>--with-gxx-include-dir=<include-files dir></code></dt> + <dd><p>Adds support for named libstdc++ include directory. For instance, + the following puts all the libstdc++ headers into a directory + called "2.97-20001008" instead of the usual + "c++/(version)". + </p> + <pre> + --with-gxx-include-dir=/foo/H-x86-gcc-3-c-gxx-inc/include/2.97-20001008</pre> </dd> + + <dt><code>--enable-cstdio </code></dt> + <dd><p>This is an abbreviated form of <code>'--enable-cstdio=stdio'</code> + (described next). This option can change the library ABI. + </p> + </dd> + + <dt><code>--enable-cstdio=OPTION </code></dt> + <dd><p>Select a target-specific I/O package. At the moment, the only + choice is to use 'stdio', a generic "C" abstraction. + The default is 'stdio'. + </p> + </dd> + + <dt><code>--enable-clocale </code></dt> + <dd><p>This is an abbreviated form of <code>'--enable-clocale=generic'</code> + (described next). This option can change the library ABI. + </p> + </dd> + + <dt><code>--enable-clocale=OPTION </code></dt> + <dd><p>Select a target-specific underlying locale package. The + choices are 'ieee_1003.1-2001' to specify an X/Open, Standard Unix + (IEEE Std. 1003.1-2001) model based on langinfo/iconv/catgets, + 'gnu' to specify a model based on functionality from the GNU C + library (langinfo/iconv/gettext) (from <a + href="http://sources.redhat.com/glibc/">glibc</a>, the GNU C + library), or 'generic' to use a generic "C" + abstraction which consists of "C" locale info. + </p> + + <p>As part of the configuration process, the "C" library is + probed both for sufficient vintage, and installed locale + data. If either of these elements are not present, the C++ + locale model default to 'generic.' On glibc-based systems of + version 2.2.5 and above with installed locale files, 'gnu' is + automatically selected. + </p> + </dd> + + <dt><code>--enable-libstdcxx-allocator </code></dt> + <dd><p>This is an abbreviated form of + <code>'--enable-libstdcxx-allocator=auto'</code> (described + next). This option can change the library ABI. + </p> + </dd> + + <dt><code>--enable-libstdcxx-allocator=OPTION </code></dt> + <dd><p>Select a target-specific underlying std::allocator. The + choices are 'new' to specify a wrapper for new, 'malloc' to + specify a wrapper for malloc, 'mt' for a fixed power of two allocator + (<a href="ext/mt_allocator.html">documented</a> under extensions), + 'pool' for the SGI pooled allocator or 'bitmap' for a bitmap allocator. + This option can change the library ABI. + </p> + </dd> + + <dt><code>--enable-cheaders=OPTION </code></dt> + <dd><p>This allows the user to define the approach taken for C header + compatibility with C++. Options are c, c_std, and c_global. + These correspond to the source directory's include/c, + include/c_std, and include/c_global, and may also include + include/c_compatibility. The default is c_global. + </p> + </dd> + + <dt><code>--enable-threads </code></dt> + <dd><p>This is an abbreviated form of <code>'--enable-threads=yes'</code> + (described next). This option can change the library ABI. + </p> + </dd> + + <dt><code>--enable-threads=OPTION </code></dt> + <dd><p>Select a threading library. A full description is given in the + general <a href="http://gcc.gnu.org/install/configure.html">compiler + configuration instructions</a>. + </p> + </dd> + + <dt><code>--enable-libstdcxx-debug </code></dt> + <dd><p>Build separate debug libraries in addition to what is normally built. + By default, the debug libraries are compiled with + <code> CXXFLAGS='-g3 -O0'</code> + , are installed in <code>${libdir}/debug</code>, and have the + same names and versioning information as the non-debug + libraries. This option is off by default. + </p> + <p>Note this make command, executed in + the build directory, will do much the same thing, without the + configuration difference and without building everything twice: + <code>make CXXFLAGS='-g3 -O0' all</code> + </p> + </dd> + + <dt><code>--enable-libstdcxx-debug-flags=FLAGS</code></dt> + + <dd><p>This option is only valid when <code> --enable-debug </code> + is also specified, and applies to the debug builds only. With + this option, you can pass a specific string of flags to the + compiler to use when building the debug versions of libstdc++. + FLAGS is a quoted string of options, like + </p> + <pre> + --enable-libstdcxx-debug-flags='-g3 -O1 -gdwarf-2'</pre> + </dd> + + <dt><code>--enable-cxx-flags=FLAGS</code></dt> + <dd><p>With this option, you can pass a string of -f (functionality) + flags to the compiler to use when building libstdc++. This + option can change the library ABI. FLAGS is a quoted string of + options, like + </p> + <pre> + --enable-cxx-flags='-fvtable-gc -fomit-frame-pointer -ansi'</pre> + <p> + Note that the flags don't necessarily have to all be -f flags, + as shown, but usually those are the ones that will make sense + for experimentation and configure-time overriding. + </p> + <p>The advantage of --enable-cxx-flags over setting CXXFLAGS in + the 'make' environment is that, if files are automatically + rebuilt, the same flags will be used when compiling those files + as well, so that everything matches. + </p> + <p>Fun flags to try might include combinations of + </p> + <pre> + -fstrict-aliasing + -fno-exceptions + -ffunction-sections + -fvtable-gc</pre> + <p>and opposite forms (-fno-) of the same. Tell us (the libstdc++ + mailing list) if you discover more! + </p> + </dd> + + <dt><code>--enable-c99 </code></dt> + <dd><p>The "long long" type was introduced in C99, along + with many other functions for wide characters, and math + classification macros, etc. If enabled, all C99 functions not + specified by the C++ standard will be put into <code>namespace + __gnu_cxx</code>, and then all these names will + be injected into namespace std, so that C99 functions can be + used "as if" they were in the C++ standard (as they + will eventually be in some future revision of the standard, + without a doubt). By default, C99 support is on, assuming the + configure probes find all the necessary functions and bits + necessary. This option can change the library ABI. + </p> + </dd> + + <dt><code>--enable-wchar_t </code>[default]</dt> + <dd><p>Template specializations for the "wchar_t" type are + required for wide character conversion support. Disabling + wide character specializations may be expedient for initial + porting efforts, but builds only a subset of what is required by + ISO, and is not recommended. By default, this option is on. + This option can change the library ABI. + </p> + </dd> + + <dt><code>--enable-long-long </code></dt> + <dd><p>The "long long" type was introduced in C99. It is + provided as a GNU extension to C++98 in g++. This flag builds + support for "long long" into the library (specialized + templates and the like for iostreams). This option is on by default: + if enabled, users will have to either use the new-style "C" + headers by default (i.e., <cmath> not <math.h>) + or add appropriate compile-time flags to all compile lines to + allow "C" visibility of this feature (on GNU/Linux, + the flag is -D_ISOC99_SOURCE, which is added automatically via + CPLUSPLUS_CPP_SPEC's addition of _GNU_SOURCE). + This option can change the library ABI. + </p> + </dd> + + <dt><code>--enable-fully-dynamic-string </code></dt> + <dd><p>This option enables a special version of basic_string avoiding + the optimization that allocates empty objects in static memory. + Mostly useful together with shared memory allocators, see PR + libstdc++/16612 for details. + </p> + </dd> + + <dt><code>--enable-concept-checks </code></dt> + <dd><p>This turns on additional compile-time checks for instantiated + library templates, in the form of specialized templates, + <a href="19_diagnostics/howto.html#3">described here</a>. They + can help users discover when they break the rules of the STL, before + their programs run. + </p> + </dd> + + <dt><code>--enable-symvers[=style] </code></dt> + + <dd><p>In 3.1 and later, tries to turn on symbol versioning in the + shared library (if a shared library has been + requested). Values for 'style' that are currently supported + are 'gnu', 'gnu-versioned-namespace', 'darwin', and + 'darwin-export'. Both gnu- options require that a recent + version of the GNU linker be in use. Both darwin options are + equivalent. With no style given, the configure script will try + to guess correct defaults for the host system, probe to see if + additional requirements are necessary and present for + activation, and if so, will turn symbol versioning on. This + option can change the library ABI. + </p> + + </dd> + + <dt><code>--enable-visibility </code></dt> + <dd><p> In 4.2 and later, enables or disables visibility attributes. + If enabled (as by default), and the compiler seems capable of + passing the simple sanity checks thrown at it, adjusts items + in namespace std, namespace std::tr1, and namespace __gnu_cxx + so that -fvisibility options work. + </p> + </dd> + + <dt><code>--enable-libstdcxx-pch </code></dt> + <dd><p>In 3.4 and later, tries to turn on the generation of + stdc++.h.gch, a pre-compiled file including all the standard + C++ includes. If enabled (as by default), and the compiler + seems capable of passing the simple sanity checks thrown at + it, try to build stdc++.h.gch as part of the make process. + In addition, this generated file is used later on (by appending <code> + --include bits/stdc++.h </code> to CXXFLAGS) when running the + testsuite. + </p> + </dd> + + <dt><code>--disable-hosted-libstdcxx </code></dt> + <dd><p>By default, a complete <em>hosted</em> C++ library is built. The + C++ Standard also describes a <em>freestanding</em> environment, + in which only a minimal set of headers are provided. This option + builds such an environment. + </p> + </dd> +</dl> +<p>Return <a href="#top">to the top of the page</a> or + <a href="http://gcc.gnu.org/libstdc++/">to the libstdc++ homepage</a>. +</p> + + +<!-- ####################################################### --> + +<hr /> +<p class="fineprint"><em> +See <a href="17_intro/license.html">license.html</a> for copying conditions. +Comments and suggestions are welcome, and may be sent to +<a href="mailto:libstdc++@gcc.gnu.org">the libstdc++ mailing list</a>. +</em></p> + + +</body> +</html> |