diff options
Diffstat (limited to 'chapter05/gcc-pass1.xml')
| -rw-r--r-- | chapter05/gcc-pass1.xml | 75 |
1 files changed, 22 insertions, 53 deletions
diff --git a/chapter05/gcc-pass1.xml b/chapter05/gcc-pass1.xml index d9c6175ff..02854618d 100644 --- a/chapter05/gcc-pass1.xml +++ b/chapter05/gcc-pass1.xml @@ -41,7 +41,7 @@ </sect2> <sect2 role="installation"> - <title>Installation of GCC</title> + <title>Installation of Cross GCC</title> <para>GCC now requires the GMP and MPFR packages. As these packages may not be included in your host distribution, they will be built with @@ -60,36 +60,17 @@ cd ../gcc-build</userinput></screen> <para>Prepare GCC for compilation:</para> -<screen><userinput remap="configure">CC="gcc -B/usr/bin/" ../gcc-&gcc-version;/configure --prefix=/tools \ - --with-local-prefix=/tools --disable-nls --disable-shared --disable-libssp \ - --disable-multilib --enable-languages=c</userinput></screen> +<screen><userinput remap="configure">../gcc-&gcc-version;/configure \ + --target=$LFS_TGT --prefix=/tools \ + --disable-nls --disable-shared --disable-multilib \ + --disable-decimal-float --disable-threads \ + --disable-libmudflap --disable-libssp \ + --disable-libgomp --enable-languages=c</userinput></screen> <variablelist> <title>The meaning of the configure options:</title> <varlistentry> - <term><envar>CC="gcc -B/usr/bin/"</envar></term> - <listitem> - <para>This forces <command>gcc</command> to prefer the linker from - the host in <filename class="directory">/usr/bin</filename>. This - is necessary on some hosts where the new <command>ld</command> - built in the previous section is not compatible with the host's - <command>gcc</command>.</para> - </listitem> - </varlistentry> - - <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>--disable-shared</parameter></term> <listitem> <para>This switch forces GCC to link its internal libraries @@ -99,37 +80,34 @@ cd ../gcc-build</userinput></screen> </varlistentry> <varlistentry> - <term><parameter>--disable-libssp</parameter></term> + <term><parameter>--disable-decimal-float, --disable-threads, --disable-libmudflap, --disable-libssp, --disable-libgomp</parameter></term> <listitem> - <para>This switch prevents a conflict with older versions of - glibc which can cause the build to fail.</para> + <para>These switches disable support for the decimal floating point extension, + threading, libmudflap, libssp and libgomp respectively. These features will fail + to compile when building a cross-compiler and are not necessary for the task of + cross-compiling the temporary libc.</para> </listitem> </varlistentry> <varlistentry> - <term><parameter>--enable-languages=c</parameter></term> + <term><parameter>--disable-multilib</parameter></term> <listitem> - <para>This option ensures that only the C compiler is built. - This is the only language needed now.</para> + <para>On x86_64, LFS does not yet support a multilib configuration. + This switch is harmless for x86.</para> </listitem> </varlistentry> <varlistentry> - <term><parameter>--disable-multilib</parameter></term> + <term><parameter>--enable-languages=c</parameter></term> <listitem> - <para>We currently only want to build support for 64-bit libraries.</para> + <para>This option ensures that only the C compiler is built. + This is the only language needed now.</para> </listitem> </varlistentry> </variablelist> - <para>The following command will compile GCC not once, but 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 is called - <quote>bootstrapping</quote>. Building GCC in this way ensures that it was - compiled correctly and is now the default configuration for the released - package. Continue with compiling by running:</para> + <para>Compile GCC by running:</para> <screen><userinput remap="make">make</userinput></screen> @@ -146,23 +124,14 @@ cd ../gcc-build</userinput></screen> <para>Using <parameter>--disable-shared</parameter> means that the <filename>libgcc_eh.a</filename> file isn't created and installed. The Glibc package depends on this library as it uses - <parameter>-lgcc_eh</parameter> within its build system. We can satisfy - that dependency by creating a symlink to <filename>libgcc.a</filename>, + <parameter>-lgcc_eh</parameter> within its build system. This dependency + can be satisfied by creating a symlink to <filename>libgcc.a</filename>, since that file will end up containing the objects normally contained in <filename>libgcc_eh.a</filename>.</para> -<screen><userinput remap="install">ln -vs libgcc.a `gcc -print-libgcc-file-name | \ +<screen><userinput remap="install">ln -vs libgcc.a `$LFS_TGT-gcc -print-libgcc-file-name | \ sed 's/libgcc/&_eh/'`</userinput></screen> - <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 remap="install">ln -vs gcc /tools/bin/cc</userinput></screen> - </sect2> <sect2 role="content"> |