source: clfs-sysroot/BOOK/final-system/common/gcc.xml@ 47ca960

<?xml version="1.0" encoding="ISO-8859-1"?>
<!DOCTYPE sect1 PUBLIC "-//OASIS//DTD DocBook XML V4.5//EN"
  "http://www.oasis-open.org/docbook/xml/4.5/docbookx.dtd" [
  <!ENTITY % general-entities SYSTEM "../../general.ent">
  %general-entities;
]>

<sect1 id="ch-system-gcc" role="wrap">
  <?dbhtml filename="gcc.html"?>

  <title>GCC-&gcc-version;</title>

  <indexterm zone="ch-system-gcc">
    <primary sortas="a-GCC">GCC</primary>
  </indexterm>

  <sect2 role="package">
    <title/>

    <para>The GCC package contains the GNU compiler collection, which includes
    the C and C++ compilers.</para>

  </sect2>

  <sect2 role="installation">
    <title>Installation of GCC</title>

    <para os="p1">To make sure that a couple of tools use the proper syntax,
    apply the following patch:</para>

<screen os="p2"><userinput>patch -Np1 -i ../&gcc-posix-patch;</userinput></screen>

    <para os="p3">The following patch fixes the searching of multilib dirs
    for specs file. The patch standardizes the gcc drivers path iteration
    functions, ensuring multilib directories are searched in the correct
    order. This fixes various issues, most noticably with libtool on
    multilib systems:</para>

<screen os="p4"><userinput>patch -Np1 -i ../&gcc-PR20425-patch;</userinput></screen>

    <para os="a">Apply a <command>sed</command> substitution that will suppress the
    installation of <filename class="libraryfile">libiberty.a</filename>. The
    version of <filename class="libraryfile">libiberty.a</filename> provided by
    Binutils will be used instead:</para>

<screen os="b"><userinput>cp libiberty/Makefile.in{,.orig}
sed 's/install_to_$(INSTALL_DEST) //' libiberty/Makefile.in.orig > libiberty/Makefile.in</userinput></screen>

    <para os="e1">GCC provides a <command>gccbug</command> script which detects at
    compile time whether mktemp is present, and hardcodes the result in a test.
    If mktemp is not found, the script will fall back to using less
    random names for temporary files.  We will be installing mktemp
    later, so the following sed will simulate its presence:</para>

<screen os="e2"><userinput>cp gcc/gccbug.in{,.orig}
sed 's/@have_mktemp_command@/yes/' gcc/gccbug.in.orig > gcc/gccbug.in</userinput></screen>

    <para os="s1">The fixincludes attempts to "fix" the system headers
    installed so far. Since gcc is cross-compiled expecting the system
    headers to be in <filename class="directory">/usr/include</filename>
    the script will be looking at host headers. The following sed prevents
    the fixincludes script from running:</para>

<screen os="s2"><userinput>cp gcc/Makefile.in{,.orig}
sed 's@\./fixinc\.sh@-c true@' gcc/Makefile.in.orig > gcc/Makefile.in</userinput></screen>

    <para os="c">The GCC documentation recommends building GCC outside of the source
    directory in a dedicated build directory:</para>

<screen os="d"><userinput>mkdir -v ../gcc-build
cd ../gcc-build</userinput></screen>

    <para os="e">Prepare GCC for compilation:</para>

<screen os="f"><userinput>../gcc-&gcc-version;/configure --prefix=/usr --libexecdir=/usr/lib \
    --build=${CLFS_HOST} --host=${CLFS_TARGET} --target=${CLFS_TARGET} \
    --enable-shared --enable-threads=posix --enable-__cxa_atexit \
    --enable-c99 --enable-long-long --enable-clocale=gnu \
    --enable-languages=c,c++ --disable-libstdcxx-pch</userinput></screen>

    <para os="g">Compile the package:</para>

<screen os="h"><userinput>make</userinput></screen>

    <para os="i">Install the package:</para>

<screen os="j"><userinput>make DESTDIR=${CLFS} install</userinput></screen>

    <para os="k">Some packages expect the C preprocessor to be installed in the
    <filename class="directory">/lib</filename> directory.
    To support those packages, create this symlink:</para>

<screen os="l"><userinput>ln -sfv ../usr/bin/cpp ${CLFS}/lib</userinput></screen>

    <para os="m">Many packages use the name <command>cc</command> to call the C
    compiler. To satisfy those packages, create a symlink:</para>

<screen os="o"><userinput>ln -sfv gcc ${CLFS}/usr/bin/cc</userinput></screen>

  </sect2>

  <sect2 id="contents-gcc" role="content">
    <title>Contents of GCC</title>

    <segmentedlist>
      <segtitle>Installed programs</segtitle>
      <segtitle>Installed libraries</segtitle>

      <seglistitem>
        <seg>c++, cc (link to gcc), cpp, g++, gcc, gccbug, and gcov</seg>
        <seg>libgcc.a, libgcc_eh.a, libgcc_s.so, libmudflap.[a,so], 
        libmudflapth.[a,so], libstdc++.[a,so], and
        libsupc++.a</seg>
      </seglistitem>
    </segmentedlist>

    <variablelist>
      <bridgehead renderas="sect3">Short Descriptions</bridgehead>
      <?dbfo list-presentation="list"?>
      <?dbhtml list-presentation="table"?>

      <varlistentry id="cc">
        <term><command>cc</command></term>
        <listitem>
          <para>The C compiler</para>
          <indexterm zone="ch-system-gcc cc">
            <primary sortas="b-cc">cc</primary>
          </indexterm>
        </listitem>
      </varlistentry>

      <varlistentry id="cpp">
        <term><command>cpp</command></term>
        <listitem>
          <para>The C preprocessor; it is used by the compiler to expand the
          #include, #define, and similar statements in the source files</para>
          <indexterm zone="ch-system-gcc cpp">
            <primary sortas="b-cpp">cpp</primary>
          </indexterm>
        </listitem>
      </varlistentry>

      <varlistentry id="c">
        <term><command>c++</command></term>
        <listitem>
          <para>The C++ compiler</para>
          <indexterm zone="ch-system-gcc c">
            <primary sortas="b-c++">c++</primary>
          </indexterm>
        </listitem>
      </varlistentry>

      <varlistentry id="g">
        <term><command>g++</command></term>
        <listitem>
          <para>The C++ compiler</para>
          <indexterm zone="ch-system-gcc g">
            <primary sortas="b-g++">g++</primary>
          </indexterm>
        </listitem>
      </varlistentry>

      <varlistentry id="gcc">
        <term><command>gcc</command></term>
        <listitem>
          <para>The C compiler</para>
          <indexterm zone="ch-system-gcc gcc">
            <primary sortas="b-gcc">gcc</primary>
          </indexterm>
        </listitem>
      </varlistentry>

      <varlistentry id="gccbug">
        <term><command>gccbug</command></term>
        <listitem>
          <para>A shell script used to help create useful bug reports</para>
          <indexterm zone="ch-system-gcc gccbug">
            <primary sortas="b-gccbug">gccbug</primary>
          </indexterm>
        </listitem>
      </varlistentry>

      <varlistentry id="gcov">
        <term><command>gcov</command></term>
        <listitem>
          <para>A coverage testing tool; it is used to analyze programs to
          determine where optimizations will have the most effect</para>
          <indexterm zone="ch-system-gcc gcov">
            <primary sortas="b-gcov">gcov</primary>
          </indexterm>
        </listitem>
      </varlistentry>

      <varlistentry id="libgcc">
        <term><filename class="libraryfile">libgcc</filename></term>
        <listitem>
          <para>Contains run-time support for <command>gcc</command></para>
          <indexterm zone="ch-system-gcc libgcc">
            <primary sortas="c-libgcc*">libgcc*</primary>
          </indexterm>
        </listitem>
      </varlistentry>

      <varlistentry id="libmudflap">
        <term><filename class="libraryfile">libmudflap</filename></term>
        <listitem>
          <para>The libmudflap libraries are used by GCC for instrumenting
          pointer and array dereferencing operations.</para>
          <indexterm zone="ch-system-gcc libmudflap">
            <primary sortas="c-libmudflap*">libmudflap*</primary>
          </indexterm>
        </listitem>
      </varlistentry>

      <varlistentry id="libstdc">
        <term><filename class="libraryfile">libstdc++</filename></term>
        <listitem>
          <para>The standard C++ library</para>
          <indexterm zone="ch-system-gcc libstdc">
            <primary sortas="c-libstdc++">libstdc++</primary>
          </indexterm>
        </listitem>
      </varlistentry>

      <varlistentry id="libsupc">
        <term><filename class="libraryfile">libsupc++</filename></term>
        <listitem>
          <para>Provides supporting routines for the C++ programming
          language</para>
          <indexterm zone="ch-system-gcc libsupc">
            <primary sortas="c-libsupc++">libsupc++</primary>
          </indexterm>
        </listitem>
      </varlistentry>

    </variablelist>

  </sect2>

</sect1>