diff options
Diffstat (limited to 'chapter05/gcc-pass2.xml')
| -rw-r--r-- | chapter05/gcc-pass2.xml | 151 |
1 files changed, 37 insertions, 114 deletions
diff --git a/chapter05/gcc-pass2.xml b/chapter05/gcc-pass2.xml index ca2a06f1c..98e3b2127 100644 --- a/chapter05/gcc-pass2.xml +++ b/chapter05/gcc-pass2.xml @@ -54,23 +54,6 @@ mv -v gmp-&gmp-version; gmp tar -xf ../mpc-&mpc-version;.tar.gz mv -v mpc-&mpc-version; mpc</userinput></screen> - <para>Once again, change the location of GCC's default dynamic linker to - use the one installed in <filename - class="directory">/tools</filename>.</para> - -<screen><userinput remap="pre">for file in gcc/config/{linux,i386/linux{,64}}.h -do - cp -uv $file{,.orig} - sed -e 's@/lib\(64\)\?\(32\)\?/ld@/tools&@g' \ - -e 's@/usr@/tools@g' $file.orig > $file - echo ' -#undef STANDARD_STARTFILE_PREFIX_1 -#undef STANDARD_STARTFILE_PREFIX_2 -#define STANDARD_STARTFILE_PREFIX_1 "/tools/lib/" -#define STANDARD_STARTFILE_PREFIX_2 ""' >> $file - touch $file.orig -done</userinput></screen> - <para>If building on x86_64, change the default directory name for 64-bit libraries to <quote>lib</quote>:</para> @@ -81,84 +64,62 @@ done</userinput></screen> ;; esac</userinput></screen> - <para>Our first build of GCC has installed a couple of internal system - headers. Normally one of them, <filename>limits.h</filename>, will in turn - include the corresponding system <filename>limits.h</filename> header, in - this case, <filename>/tools/include/limits.h</filename>. However, at the - time of the first build of gcc <filename>/tools/include/limits.h</filename> - did not exist, so the internal header that GCC installed is a partial, - self-contained file and does not include the extended features of the - system header. This was adequate for building the temporary libc, but this - build of GCC now requires the full internal header. Create a full version - of the internal header using a command that is identical to what the GCC - build system does in normal circumstances:</para> - -<screen><userinput remap="pre">cat gcc/limitx.h gcc/glimits.h gcc/limity.h > \ - `dirname $($LFS_TGT-gcc -print-libgcc-file-name)`/include-fixed/limits.h</userinput></screen> -<!-- - <para>For x86 machines, the limited number of registers is a bottleneck - for the system. Free one up by not using a frame pointer that is not - needed:</para> - -<screen><userinput remap="pre">case `uname -m` in - i?86) sed -i 's/^T_CFLAGS =$/& -fomit-frame-pointer/' gcc/Makefile.in ;; -esac</userinput></screen> ---> <para>Create a separate build directory again:</para> <screen><userinput remap="pre">mkdir -v build cd build</userinput></screen> + <para>Create a symlink that allos libgcc to be built with posix threads + support:</para> + +<screen><userinput remap="pre">mkdir -pv $LFS_TGT/libgcc +ln -s ../../../libgcc/gthr-posix.h $LFS_TGT/libgcc/gthr-default.h</userinput></screen> + <para>Before starting to build GCC, remember to unset any environment variables that override the default optimization flags.</para> <para>Now prepare GCC for compilation:</para> -<screen><userinput remap="configure">CC=$LFS_TGT-gcc \ -CXX=$LFS_TGT-g++ \ -AR=$LFS_TGT-ar \ -RANLIB=$LFS_TGT-ranlib \ -../configure \ - --prefix=/tools \ - --with-local-prefix=/tools \ - --with-native-system-header-dir=/tools/include \ - --enable-languages=c,c++ \ - --disable-libstdcxx-pch \ +<screen><userinput remap="configure">../configure \ + --build=$(../config.guess) \ + --host=$LFS_TGT \ + --prefix=/usr \ + CC_FOR_TARGET=$LFS_TGT-gcc \ + --with-build-sysroot=$LFS \ + --enable-initfini-array \ + --disable-nls \ --disable-multilib \ - --disable-bootstrap \ - --disable-libgomp</userinput></screen> + --disable-decimal-float \ + --disable-libatomic \ + --disable-libgomp \ + --disable-libquadmath \ + --disable-libssp \ + --disable-libvtv \ + --disable-libstdcxx \ + --enable-languages=c,c++</userinput></screen> <variablelist> - <title>The meaning of the new configure options:</title> - - <varlistentry> - <term><parameter>--enable-languages=c,c++</parameter></term> - <listitem> - <para>This option ensures that both the C and C++ compilers are - built.</para> - </listitem> - </varlistentry> + <title>The meaning of the new configure options:</title><!-- WIP --> <varlistentry> - <term><parameter>--disable-libstdcxx-pch</parameter></term> + <term><parameter>-with-build-sysroot=$LFS</parameter></term> <listitem> - <para>Do not build the pre-compiled header (PCH) for - <filename class="libraryfile">libstdc++</filename>. It takes up a - lot of space, and we have no use for it.</para> + <para>Normally, using <parameter>--host=</parameter> ensures that + a cross-compiler is used for building gcc, and that compiler knows + that it has to look for headers and libraries in <filename + class="directory">$LFS</filename>. But the build system of GCC uses + other tools, which are not aware of this location. This switch is + needed to have them find the needed files in <filename + class="directory">$LFS</filename>, and not on the host.</para> </listitem> </varlistentry> <varlistentry> - <term><parameter>--disable-bootstrap</parameter></term> + <term><parameter>--enable-initfini-array</parameter></term> <listitem> - <para>For native builds of GCC, the default is to do a "bootstrap" - build. This 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. The second and third - iterations are compared to make sure it can reproduce itself - flawlessly. This also implies that it was compiled correctly. - However, the LFS build method should provide a solid compiler - without the need to bootstrap each time.</para> + <para>This option is automatically enabled when building a native + compiler with a native compiler on x86. But here, we build with + a cross compiler, so we need to explicitely set this option.</para> </listitem> </varlistentry> @@ -170,7 +131,7 @@ RANLIB=$LFS_TGT-ranlib \ <para>Install the package:</para> -<screen><userinput remap="install">make install</userinput></screen> +<screen><userinput remap="install">make DESTDIR=$LFS install</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 @@ -179,45 +140,7 @@ RANLIB=$LFS_TGT-ranlib \ <command>cc</command> leaves the system administrator free to decide which C compiler to install:</para> -<screen><userinput remap="install">ln -sv gcc /tools/bin/cc</userinput></screen> - - <caution> - <para>At this point, it is imperative to stop and ensure that the basic - functions (compiling and linking) of the new toolchain are working as - expected. To perform a sanity check, run the following commands:</para> - -<screen><userinput>echo 'int main(){}' > dummy.c -cc dummy.c -readelf -l a.out | grep ': /tools'</userinput></screen> - - <para>If everything is working correctly, there should be no errors, - and the output of the last command will be of the form:</para> - -<screen><computeroutput>[Requesting program interpreter: /tools/lib64/ld-linux-x86-64.so.2]</computeroutput></screen> - - <para>Note that the dynamic linker will be /tools/lib/ld-linux.so.2 - for 32-bit machines.</para> - - <para>If the output is not shown as above or there was no output at all, - then something is wrong. Investigate and retrace the steps to find out - where the problem is and correct it. This issue must be resolved before - continuing on. First, perform the sanity check again, using - <command>gcc</command> instead of <command>cc</command>. If this works, - then the <filename class="symlink">/tools/bin/cc</filename> symlink is - missing. Install the symlink as per above. - Next, ensure that the <envar>PATH</envar> is correct. This - can be checked by running <command>echo $PATH</command> and verifying that - <filename class="directory">/tools/bin</filename> is at the head of the - list. If the <envar>PATH</envar> is wrong it could mean that you are not - logged in as user <systemitem class="username">lfs</systemitem> or that - something went wrong back in <xref linkend="ch-preps-settingenviron" - role="."/></para> - - <para>Once all is well, clean up the test files:</para> - -<screen><userinput>rm -v dummy.c a.out</userinput></screen> - - </caution> +<screen><userinput remap="install">ln -sv gcc $LFS/usr/bin/cc</userinput></screen> </sect2> |