source: chapter05/glibc-inst.xml@ 72853dc

<sect2><title>&nbsp;</title><para>&nbsp;</para></sect2>

<sect2>
<title>Glibc installation</title>

<para>Before starting to install Glibc, you must <userinput>cd</userinput>
into the <filename>glibc-&glibc-version;</filename> directory and unpack
Glibc-linuxthreads in that directory, not in <filename>/usr/src</filename> as
you would normally do.</para>

<para>This package is known to behave badly when you have changed its
default optimization flags (including the -march and -mcpu options).
Therefore, if you have defined any environment variables that override
default optimizations, such as CFLAGS and CXXFLAGS, we recommend unsetting
them when building Glibc.</para>

<para>Basically, compiling Glibc in any other way than the book suggests
is putting your system at a very high risk.</para>

<para>The documentation that comes with Glibc recommends to build the package
not in the source directory but in a separate, dedicated directory:</para>

<para><screen><userinput>mkdir ../glibc-build &amp;&amp;
cd ../glibc-build</userinput></screen></para>

<para>Next, prepare Glibc to be compiled:</para>

<para><screen><userinput>CFLAGS="-O2 -pipe" \
&nbsp;&nbsp;&nbsp;&nbsp;../glibc-&glibc-version;/configure --prefix=/stage1 \
&nbsp;&nbsp;&nbsp;&nbsp;--disable-profile --enable-add-ons \
&nbsp;&nbsp;&nbsp;&nbsp;--with-headers=/stage1/include \
&nbsp;&nbsp;&nbsp;&nbsp;--with-binutils=/stage1/bin \
&nbsp;&nbsp;&nbsp;&nbsp;--without-gd</userinput></screen></para>

<para>The meaning of the configure options are:</para>

<itemizedlist>
<listitem><para><userinput>--disable-profile</userinput>: This disables the
building of the libraries with profiling information. Omit this option if you
plan to do profiling.</para></listitem>

<listitem><para><userinput>--enable-add-ons</userinput>: This enables any
add-ons that we installed with Glibc, in our case Linuxthreads.</para></listitem>

<listitem><para><userinput>--libexecdir=/usr/bin</userinput>: This will
cause the <filename>pt_chown</filename> program to be installed in the
<filename>/usr/bin</filename> directory.</para></listitem>
</itemizedlist>

<para>During this stage you will see the following warning:</para>

<blockquote><screen>configure: warning:
*** These auxiliary programs are missing or too old: msgfmt
*** some features will be disabled.
*** Check the INSTALL file for required versions.</screen></blockquote>

<para>The missing <filename>msgfmt</filename> program (from the Gettext
package, which we'll install later) won't cause any problems. The
<filename>msgfmt</filename> is used to generate the binary translation
files that can make your system talk in a different language. Because these
translation files have already been generated for you, there is no need for
<filename>msgfmt</filename>. You'd only need the program if you change the
translation source files (the <filename>*.po</filename> files in the
<filename class="directory">po</filename> subdirectory), which
would require you to regenerate the binary files.</para>

<para>Continue with compiling the package:</para>

<para><screen><userinput>make
make check
make install</userinput></screen></para>

<para>The locales (used by Glibc to make your Linux system talk in a different
language) weren't installed when you ran the previous command, so we have to
do that ourselves now:</para>

<para><screen><userinput>make localedata/install-locales</userinput></screen></para>

<para>An alternative to running the previous command is to install only those
locales which you need or want. This can be achieved using the localedef
command. Information on this can be found in the <filename>INSTALL</filename>
file in the <filename>glibc-&glibc-version;</filename> tree.</para>

</sect2>