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diff --git a/chapter05/gcc-pass1-inst.xml b/chapter05/gcc-pass1-inst.xml new file mode 100644 index 000000000..605f7ee6a --- /dev/null +++ b/chapter05/gcc-pass1-inst.xml @@ -0,0 +1,114 @@ +<sect2><title> </title><para> </para></sect2> + +<sect2> +<title>Installation of GCC</title> + +<para>We won't be needing a C++ compiler until Chapter 6. So, only +the gcc-core tarball needs to be unpacked at this time.</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 +or modifying them when building GCC.</para> + +<para><screen><userinput>patch -Np1 -i ../gcc-&gcc-version;-mmap_test.patch +patch -Np1 -i ../gcc-&gcc-version;-no_fixedincludes.patch +patch -Np1 -i ../gcc-&gcc-version;-libstdc++_no_debug.patch +patch -Np1 -i ../gcc-&gcc-version;-libgcc_no_debug.patch</userinput></screen></para> + +<para>It is recommended by the GCC installation documentation to build +GCC outside of the source directory in a dedicated directory:</para> + +<para><screen><userinput>mkdir ../gcc-build +cd ../gcc-build</userinput></screen></para> + +<para>Prepare GCC to be compiled:</para> + +<para><screen><userinput>CFLAGS="-O2 -pipe" \ + ../gcc-&gcc-version;/configure --prefix=/stage1 \ + --with-local-prefix=/stage1 \ + --disable-nls --enable-shared </userinput></screen></para> + +<para>The meaning of the configure options are:</para> + +<itemizedlist> +<listitem><para><userinput>--prefix=/static</userinput>: This is NOT a +typo. GCC hard codes some paths while compiling and so we need to pass +<filename class="directory">/static</filename> as the prefix during the +configure stage. We will pass the real installation prefix (<filename +class="directory">$LFS/static</filename>) during the installation +stage later on.</para></listitem> + +<listitem><para><userinput>--disable-shared</userinput>: This prevents the +build of dynamic libraries. They are useless to us at the moment. We'll +create them when we reinstall GCC in chapter 6.</para></listitem> + +<listitem><para><userinput>--with-as=$LFS/static/bin/as and +--with-ld=$LFS/static/bin/ld</userinput>: GCC can be miscompiled if your +host distribution's Binutils package is quite old. We need a good working +static GCC until we reinstall GCC later in chapter 6. So by using +<filename>as</filename> and <filename>ld</filename> from the Binutils +package we compiled earlier in this chapter we ensure that GCC will work +correctly.</para></listitem> +</itemizedlist> + +<para>Continue with compiling the package:</para> + +<para><screen><userinput>make BOOT_LDFLAGS="-static -s" \ + BOOT_CFLAGS="-O2 -pipe" \ + STAGE1_CFLAGS="-pipe" bootstrap</userinput></screen></para> + +<para>The meaning of the make options are:</para> + +<itemizedlist> +<listitem><para><userinput>BOOT_LDFLAGS="-static"</userinput>: This is +GCC's equivalent to make LDFLAGS="-static" as we use with other packages to +compile them statically.</para></listitem> + +<listitem><para><userinput>bootstrap</userinput>: The +<emphasis>bootstrap</emphasis> target doesn't just compile GCC, but it +compiles GCC a second time. It uses the first compiled programs to compile +itself a second and third time to make sure the compiler was compiled properly +and can compile itself properly.</para></listitem> +</itemizedlist> + +<para><screen><userinput>make -k check</userinput></screen></para> + +<para>And finish off installing the package:</para> + +<para><screen><userinput>make install</userinput></screen></para> + +<para>The meaning of the make option is:</para> + +<itemizedlist> +<listitem><para><userinput>install-no-fixedincludes</userinput>: This prevents +the fixincludes script from running. Preventing this is necessary because +under normal circumstances the GCC installation will run the fixincludes +script which scans your system for header files that need to be fixed. It +might find that the Glibc header files of your host system need to be fixed. +If so, it will fix them and put them in +<filename>$LFS/static/lib/gcc-lib/i686-pc-linux-gnu/3.2</filename>. Later on +in chapter 6 you will install Glibc which will put its header files in +<filename>/usr/include</filename>. Next you will install other programs that +use the Glibc headers and GCC will look in +<filename>/static/lib/gcc-lib</filename> before looking in +<filename>/usr/include</filename>, with the result of finding and using the +fixed Glibc header files from your host distribution, which are probably +incompatible with the Glibc version actually used on the LFS +system.</para></listitem> +</itemizedlist> + +<para>As the finishing touch we'll create the <filename +class="symlink">$LFS/static/bin/cc</filename> symlink. A lot of programs +and scripts try to run <userinput>cc</userinput> instead of +<userinput>gcc</userinput> This is to keep programs generic and usable on +all kinds of Unix systems. Not everybody has GNU CC installed. Just running +<userinput>cc</userinput> (C Compiler) leaves the user free to decide which +C compiler to install. The symlink will point to the system's default +compiler.</para> + +<para><screen><userinput>ln -sf gcc /stage1/bin/cc</userinput></screen></para> + +</sect2> + |