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Diffstat (limited to 'chapter05/gcc-pass1.xml')
| -rw-r--r-- | chapter05/gcc-pass1.xml | 102 |
1 files changed, 94 insertions, 8 deletions
diff --git a/chapter05/gcc-pass1.xml b/chapter05/gcc-pass1.xml index 39b343a2e..503438558 100644 --- a/chapter05/gcc-pass1.xml +++ b/chapter05/gcc-pass1.xml @@ -7,7 +7,12 @@ <title>GCC-&gcc-version; - Pass 1</title> <?dbhtml filename="gcc-pass1.html"?> +<indexterm zone="ch-tools-gcc-pass1"> +<primary sortas="a-GCC">GCC</primary> +<secondary>tools, pass 1</secondary></indexterm> + <sect2 role="package"><title/> +<xi:include xmlns:xi="http://www.w3.org/2003/XInclude" href="../chapter06/gcc.xml" xpointer="xpointer(/sect1/sect2[1]/para[1])"/> <segmentedlist> <segtitle>&buildtime;</segtitle> @@ -15,36 +20,117 @@ <seglistitem><seg>4.4 SBU</seg><seg>300 MB</seg></seglistitem> </segmentedlist> +<xi:include xmlns:xi="http://www.w3.org/2003/XInclude" href="../chapter06/gcc.xml" xpointer="xpointer(/sect1/sect2[1]/segmentedlist[2])"/> + </sect2> <sect2 role="installation"> <title>Installation of GCC</title> -<para>Create a build dir:</para> +<para>Unpack only the gcc-core tarball because neither the C++ +compiler nor the test suite will be needed here.</para> + +<para>This package is known to have issues when its default +optimization flags (including the <parameter>-march</parameter> and +<parameter>-mcpu</parameter> options) are changed. If any environment +variables that override default optimizations have been defined, such +as <envar>CFLAGS</envar> and <envar>CXXFLAGS</envar>, +unset them when building GCC.</para> + +<para>The GCC documentation recommends building GCC outside of the +source directory in a dedicated build directory:</para> <screen><userinput>mkdir ../gcc-build cd ../gcc-build</userinput></screen> <para>Prepare GCC for compilation:</para> -<!--NEW--> -<screen><userinput>CC="gcc -B/usr/bin" ../gcc-&gcc-version;/configure \ - --prefix=/tools --libexecdir=/tools/lib \ - --with-local-prefix=/tools --disable-nls \ - --enable-shared --enable-languages=c</userinput></screen> +<screen><userinput>../gcc-&gcc-version;/configure --prefix=/tools \ + --libexecdir=/tools/lib --with-local-prefix=/tools \ + --disable-nls --enable-shared --enable-languages=c</userinput></screen> + +<para>The meaning of the configure options:</para> + +<variablelist> +<varlistentry> +<term><parameter>--with-local-prefix=/tools</parameter></term> +<listitem><para>The purpose of this switch is to remove <filename class="directory">/usr/local/include</filename> +from <command>gcc</command>'s include search path. This is not absolutely +essential, however, it helps to minimize the influence of the host +system.</para> +</listitem> +</varlistentry> + +<varlistentry> +<term><parameter>--enable-shared</parameter></term> +<listitem><para>This switch may seem counter-intuitive at first. +However, this switch allows the building of +<filename class="libraryfile">libgcc_s.so.1</filename> and +<filename class="libraryfile">libgcc_eh.a</filename>, and having +<filename class="libraryfile">libgcc_eh.a</filename> available ensures that the configure +script for Glibc (the next package we compile) produces the proper +results. Note that the GCC binaries will still be linked statically +because this is controlled by the <parameter>-static</parameter> value of +the <envar>BOOT_LDFLAGS</envar> variable in the next +step.</para></listitem> +</varlistentry> + +<varlistentry> +<term><parameter>--enable-languages=c</parameter></term> +<listitem><para>This option ensures that only the C compiler is built. +This option is only needed when you have downloaded and unpacked the +full GCC tarball, as opposed to just the gcc-core +tarball.</para></listitem> +</varlistentry> +</variablelist> <para>Continue with compiling the package:</para> <screen><userinput>make BOOT_LDFLAGS="-static" bootstrap</userinput></screen> -<para>Now install the package:</para> +<para>The meaning of the make parameters:</para> + +<variablelist> +<varlistentry> +<term><parameter>BOOT_LDFLAGS="-static"</parameter></term> +<listitem><para>This tells GCC to link its programs statically.</para></listitem> +</varlistentry> + +<varlistentry> +<term><parameter>bootstrap</parameter></term> +<listitem><para>This target does not just compile GCC, but compiles it +several times. It uses the programs compiled in a first round to +compile itself a second time, and then again a third time. It then +compares these second and third compiles to make sure it can reproduce +itself flawlessly. This also implies that it was compiled +correctly.</para></listitem> +</varlistentry> +</variablelist> + +<para>Compilation is now complete. At this point, the test suite would +normally be run, but, as mentioned before, the test suite framework is +not in place yet. The benefits of running the tests at this point +are minimal since the programs from this first pass will soon be +replaced.</para> + +<para>Install the package:</para> <screen><userinput>make install</userinput></screen> -<para>Create a symlink:</para> +<para>As a finishing touch, create a symlink. Many programs and +scripts run <command>cc</command> instead of <command>gcc</command>, which is used to keep programs generic +and therefore usable on all kinds of UNIX systems where the GNU C compiler +is not always installed. Running <command>cc</command> leaves the system administrator +free to decide which C compiler to install.</para> <screen><userinput>ln -s gcc /tools/bin/cc</userinput></screen> </sect2> +<sect2 role="content"><title/> +<para>Details on this package are located in <xref +linkend="contents-gcc" role="."/></para> +</sect2> + </sect1> + |