lfs-book/chapter05/libstdc++.xml

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<sect1 id="ch-tools-libstdcpp" role="wrap">
  <?dbhtml filename="gcc-libstdc++.html"?>

  <sect1info condition="script">
    <productname>gcc-libstdc++</productname>
    <productnumber>&gcc-version;</productnumber>
    <address>&gcc-url;</address>
  </sect1info>

  <title>Libstdc++ from GCC-&gcc-version;</title>

  <indexterm zone="ch-tools-libstdcpp">
    <primary sortas="a-GCC">GCC</primary>
    <secondary>tools, libstdc++</secondary>
  </indexterm>

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

    <para>Libstdc++ is the standard C++ library. It is needed 
    to compile C++ code
    (part of GCC is written in C++), but we had to defer its installation
    when we built <xref linkend="ch-tools-gcc-pass1"/>
    because it depends on glibc, which was not yet available in /tools.
    </para>

    <segmentedlist>
      <segtitle>&buildtime;</segtitle>
      <segtitle>&diskspace;</segtitle>

      <seglistitem>
        <seg>&libstdcpp-ch5-sbu;</seg>
        <seg>&libstdcpp-ch5-du;</seg>
      </seglistitem>
    </segmentedlist>

  </sect2>

  <sect2 role="installation">
    <title>Installation of Target Libstdc++</title>

    <note>
      <para><application>Libstdc++</application> is part of the GCC sources.
      You should first unpack the GCC tarball and change to the
      <filename>gcc-&gcc-version;</filename> directory.</para>
    </note>

    <para>Create a separate build directory for Libstdc++ and enter it:</para>

<screen><userinput remap="pre">mkdir -v build
cd       build</userinput></screen>

    <para>Prepare Libstdc++ for compilation:</para>

<screen><userinput remap="configure">../libstdc++-v3/configure           \
    --host=$LFS_TGT                 \
    --prefix=/tools                 \
    --disable-multilib              \
    --disable-nls                   \
    --disable-libstdcxx-threads     \
    --disable-libstdcxx-pch         \
    --with-gxx-include-dir=/tools/$LFS_TGT/include/c++/&gcc-version;</userinput></screen>

    <variablelist>
      <title>The meaning of the configure options:</title>

      <varlistentry>
        <term><parameter>--host=...</parameter></term>
        <listitem>
          <para>Indicates to use the cross compiler we have just built
          instead of the one in <filename>/usr/bin</filename>.</para>
        </listitem>
      </varlistentry>

      <varlistentry>
        <term><parameter>--disable-libstdcxx-threads</parameter></term>
        <listitem>
          <para>Since gcc-pass1 is built without thread support, the C++
          thread library cannot be built either.</para>
        </listitem>
      </varlistentry>

      <varlistentry>
        <term><parameter>--disable-libstdcxx-pch</parameter></term>
        <listitem>
          <para>This switch prevents the installation of precompiled
          include files, which are not needed at this stage.</para>
        </listitem>
      </varlistentry>

      <varlistentry>
        <term><parameter>--with-gxx-include-dir=/tools/$LFS_TGT/include/c++/&gcc-version;</parameter></term>
        <listitem>
          <para>This is the location where the standard include files are
          searched by the C++ compiler. In a normal build, this information
          is automatically passed to the Libstdc++ <command>configure</command>
          options from the top level directory. In our case, this information
          must be explicitly given.</para>
        </listitem>
      </varlistentry>

    </variablelist>

    <para>Compile libstdc++ by running:</para>

<screen><userinput remap="make">make</userinput></screen>

    <para>Install the library:</para>

<screen><userinput remap="install">make install</userinput></screen>

  </sect2>

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

    <para>Details on this package are located in
    <xref linkend="contents-gcc" role="."/></para>

  </sect2>

</sect1>