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@@ -3,7 +3,7 @@
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<sect2>
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<title>Installation of GCC</title>
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-<para>We won't be needing a C++ compiler until Chapter 6. So, only
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+<para>We won't be needing a C++ compiler until the next chapter. So, only
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the gcc-core tarball needs to be unpacked at this time.</para>
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<para>This package is known to behave badly when you have changed its
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@@ -28,79 +28,58 @@ cd ../gcc-build</userinput></screen></para>
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--disable-nls --enable-shared \
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--enable-languages=c</userinput></screen></para>
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-<para>The meaning of the configure options are:</para>
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+<para>The meaning of the new configure options is:</para>
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<itemizedlist>
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-<listitem><para><userinput>--prefix=/static</userinput>: This is NOT a
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-typo. GCC hard codes some paths while compiling and so we need to pass
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-<filename class="directory">/static</filename> as the prefix during the
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-configure stage. We will pass the real installation prefix (<filename
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-class="directory">$LFS/static</filename>) during the installation
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-stage later on.</para></listitem>
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-
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-<listitem><para><userinput>--disable-shared</userinput>: This prevents the
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-build of dynamic libraries. They are useless to us at the moment. We'll
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-create them when we reinstall GCC in chapter 6.</para></listitem>
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-
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-<listitem><para><userinput>--with-as=$LFS/static/bin/as and
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---with-ld=$LFS/static/bin/ld</userinput>: GCC can be miscompiled if your
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-host distribution's Binutils package is quite old. We need a good working
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-static GCC until we reinstall GCC later in chapter 6. So by using
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-<filename>as</filename> and <filename>ld</filename> from the Binutils
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-package we compiled earlier in this chapter we ensure that GCC will work
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-correctly.</para></listitem>
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+<listitem><para><userinput>--with-local-prefix=/stage1</userinput>: The
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+purpose of this switch is to remove <filename>/usr/local/include</filename>
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+from <userinput>gcc</userinput>'s include search path. This is not absolutely
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+essential, but we want to try and minimize the influence from the host system,
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+so this seems a logical thing to do.</para></listitem>
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+
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+<listitem><para><userinput>--enable-shared</userinput>: This switch may
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+seem counter-intuitive at first. But using it allows the building of
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+<filename>libgcc_s.so.1</filename> and <filename>libgcc_eh.a</filename>, and
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+having <filename>libgcc_eh.a</filename> available ensures that the configure
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+script for Glibc (the next package we compile) produces the proper results.
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+Please note that the <userinput>gcc</userinput> binaries will still be linked
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+statically, as this is controlled by the <userinput>-static</userinput>
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+value of BOOT_LDFLAGS further on.</para></listitem>
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+
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+<listitem><para><userinput>--enable-languages=c</userinput>: This will build
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+only the C compiler from the GCC package. We won't be needing anything else
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+during this chapter.</para></listitem>
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</itemizedlist>
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<para>Continue with compiling the package:</para>
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<para><screen><userinput>make BOOT_LDFLAGS="-static" bootstrap</userinput></screen></para>
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-<para>The meaning of the make options are:</para>
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+<para>The meaning of the make parameters is:</para>
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<itemizedlist>
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-<listitem><para><userinput>BOOT_LDFLAGS="-static"</userinput>: This is
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-GCC's equivalent to make LDFLAGS="-static" as we use with other packages to
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-compile them statically.</para></listitem>
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-
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-<listitem><para><userinput>bootstrap</userinput>: The
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-<emphasis>bootstrap</emphasis> target doesn't just compile GCC, but it
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-compiles GCC a second time. It uses the first compiled programs to compile
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-itself a second and third time to make sure the compiler was compiled properly
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-and can compile itself properly.</para></listitem>
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+<listitem><para><userinput>BOOT_LDFLAGS="-static"</userinput>: This tells
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+GCC to link its programs statically.</para></listitem>
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+
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+<listitem><para><userinput>bootstrap</userinput>: This target doesn't just
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+compile GCC, but compiles it several times. It uses the programs compiled in
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+a first round to compile itself a second time, and then again a third time.
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+It then compares these second and third compiles to make sure it can
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+reproduce itself flawlessly, which most probably means that it was
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+compiled correctly.</para></listitem>
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</itemizedlist>
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-<para>And finish off installing the package:</para>
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+<para>And install the package:</para>
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<para><screen><userinput>make install</userinput></screen></para>
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-<para>The meaning of the make option is:</para>
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-
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-<itemizedlist>
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-<listitem><para><userinput>install-no-fixedincludes</userinput>: This prevents
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-the fixincludes script from running. Preventing this is necessary because
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-under normal circumstances the GCC installation will run the fixincludes
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-script which scans your system for header files that need to be fixed. It
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-might find that the Glibc header files of your host system need to be fixed.
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-If so, it will fix them and put them in
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-<filename>$LFS/static/lib/gcc-lib/i686-pc-linux-gnu/3.2</filename>. Later on
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-in chapter 6 you will install Glibc which will put its header files in
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-<filename>/usr/include</filename>. Next you will install other programs that
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-use the Glibc headers and GCC will look in
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-<filename>/static/lib/gcc-lib</filename> before looking in
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-<filename>/usr/include</filename>, with the result of finding and using the
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-fixed Glibc header files from your host distribution, which are probably
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-incompatible with the Glibc version actually used on the LFS
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-system.</para></listitem>
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-</itemizedlist>
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-
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-<para>As the finishing touch we'll create the <filename
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-class="symlink">$LFS/static/bin/cc</filename> symlink. A lot of programs
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-and scripts try to run <userinput>cc</userinput> instead of
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-<userinput>gcc</userinput> This is to keep programs generic and usable on
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-all kinds of Unix systems. Not everybody has GNU CC installed. Just running
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-<userinput>cc</userinput> (C Compiler) leaves the user free to decide which
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-C compiler to install. The symlink will point to the system's default
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-compiler.</para>
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+<para>As a finishing touch we'll create the <filename
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+class="symlink">/stage1/bin/cc</filename> symlink. Many programs and
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+scripts run <userinput>cc</userinput> instead of <userinput>gcc</userinput>,
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+a thing meant to keep programs generic and therefore usable on all kinds of
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+Unix systems. Not everybody has the GNU C compiler installed. Simply running
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+<userinput>cc</userinput> leaves the system administrator free to decide what
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+C compiler to install, as long as there's a symlink pointing to it:</para>
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<para><screen><userinput>ln -sf gcc /stage1/bin/cc</userinput></screen></para>
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Gerard Beekmans