1 <sect1 id="ch-system-gcc" xreflabel="GCC">
2 <title>Installing GCC-&gcc-version;</title>
3 <?dbhtml filename="gcc.html" dir="chapter06"?>
5 <para>The GCC package contains the GNU compiler collection, among them
6 the C and C++ compilers.</para>
8 <screen>&buildtime; &gcc-time;
9 &diskspace; &gcc-compsize;</screen>
11 <literallayout>Official download location for GCC (&gcc-version;):
12 <ulink url="ftp://ftp.gnu.org/pub/gnu/gcc/"/>
14 <ulink url="&patches-root;&gcc-nofixincludes-patch;"/></literallayout>
18 <sect2><title> </title><para> </para></sect2>
21 <title>Installation of GCC</title>
23 <para>This package is known to behave badly when you have changed its
24 default optimization flags (including the -march and -mcpu options).
25 Therefore, if you have defined any environment variables that override
26 default optimizations, such as CFLAGS and CXXFLAGS, we recommend unsetting
27 or modifying them when building GCC.</para>
29 <para>Unpack the GCC-core <emphasis>and</emphasis> the GCC-g++ tarball -- they
30 will unfold into the same directory. You should likewise extract the
31 GCC-testsuite package. The full GCC package contains even more
32 compilers. Instructions for building these can be found at
33 <ulink url="&blfs-root;view/stable/general/gcc.html"/>.</para>
35 <para>First apply only the No-Fixincludes patch (and <emphasis>not</emphasis>
36 the Specs patch) also used in the previous chapter:</para>
38 <screen><userinput>patch -Np1 -i ../&gcc-nofixincludes-patch;</userinput></screen>
40 <para>Now apply a sed substitution that will suppress the installation of
41 <filename>libiberty.a</filename>. We want to use the version of
42 <filename>libiberty.a</filename> provided by Binutils:</para>
44 <screen><userinput>sed -i 's/install_to_$(INSTALL_DEST) //' libiberty/Makefile.in</userinput></screen>
46 <para>The GCC documentation recommends building GCC outside of the source
47 directory in a dedicated build directory:</para>
49 <screen><userinput>mkdir ../gcc-build
50 cd ../gcc-build</userinput></screen>
52 <para>Now prepare GCC for compilation:</para>
54 <screen><userinput>../&gcc-dir;/configure --prefix=/usr \
55 --enable-shared --enable-threads=posix \
56 --enable-__cxa_atexit --enable-clocale=gnu \
57 --enable-languages=c,c++</userinput></screen>
59 <para>Compile the package:</para>
61 <screen><userinput>make</userinput></screen>
63 <important><para>The test suite for GCC in this section is considered
64 <emphasis>critical</emphasis>. Our advice is to not skip it under any
65 circumstance.</para></important>
67 <para>Test the results, but don't stop at errors (you'll remember the few
70 <screen><userinput>make -k check</userinput></screen>
72 <para>The test suite notes from <xref linkend="ch-tools-gcc-pass2"/> are still very
73 much appropriate here. Be sure to refer back there should you have any
76 <para>And install the package:</para>
78 <screen><userinput>make install</userinput></screen>
80 <para>Some packages expect the C PreProcessor to be installed in the
81 <filename>/lib</filename> directory.
82 To honor those packages, create this symlink:</para>
84 <screen><userinput>ln -s ../usr/bin/cpp /lib</userinput></screen>
86 <para>Many packages use the name <command>cc</command> to call the C
87 compiler. To satisfy those packages, create a symlink:</para>
89 <screen><userinput>ln -s gcc /usr/bin/cc</userinput></screen>
91 <note><para>At this point it is strongly recommended to repeat the sanity check
92 we performed earlier in this chapter. Refer back to
93 <xref linkend="ch-system-adjustingtoolchain"/> and repeat the check. If the results
94 are wrong, then most likely you erroneously applied the GCC Specs patch from
95 <xref linkend="chapter-temporary-tools"/>.</para></note>