6.10. GCC-4.6.0

The GCC package contains the GNU compiler collection, which includes the C and C++ compilers.

6.10.1. Installation of GCC

The following patch contains a number of updates to the 4.6.0 branch by the GCC developers:

patch -Np1 -i ../gcc-4.6.0-branch_update-1.patch

Make a couple of essential adjustments to the specs file to ensure GCC uses our build environment:

patch -Np1 -i ../gcc-4.6.0-specs-1.patch

Change the StartFile Spec and Standard Include Dir so that GCC looks in /tools:

echo -en '#undef STANDARD_INCLUDE_DIR\n#define STANDARD_INCLUDE_DIR "/tools/include/"\n\n' >> gcc/config/rs6000/sysv4.h
echo -en '\n#undef STANDARD_STARTFILE_PREFIX_1\n#define STANDARD_STARTFILE_PREFIX_1 "/tools/lib/"\n' >> gcc/config/rs6000/sysv4.h
echo -en '\n#undef STANDARD_STARTFILE_PREFIX_2\n#define STANDARD_STARTFILE_PREFIX_2 ""\n' >> gcc/config/rs6000/sysv4.h

Also, we need to set the directory searched by the fixincludes process for system headers, so it won't look at the host's headers:

cp -v gcc/Makefile.in{,.orig}
sed -e 's@\(^NATIVE_SYSTEM_HEADER_DIR =\).*@\1 /tools/include@g' \
    gcc/Makefile.in.orig > gcc/Makefile.in

The GCC documentation recommends building GCC outside of the source directory in a dedicated build directory:

mkdir -v ../gcc-build
cd ../gcc-build

Before starting to build GCC, remember to unset any environment variables that override the default optimization flags.

Prepare GCC for compilation:

../gcc-4.6.0/configure --prefix=/tools \
  --build=${CLFS_HOST} --host=${CLFS_TARGET} --target=${CLFS_TARGET} \
  --with-local-prefix=/tools --enable-long-long --enable-c99 \
  --enable-shared --enable-threads=posix --enable-__cxa_atexit \
  --disable-nls --enable-languages=c,c++ --disable-libstdcxx-pch \
  --disable-multilib

The meaning of the new configure options:

--disable-libstdcxx-pch

Do not build the pre-compiled header (PCH) for libstdc++. It takes up a lot of space, and we have no use for it.

The following will prevent GCC from looking in the wrong directories for headers and libraries:

cp -v Makefile{,.orig}
sed "/^HOST_\(GMP\|PPL\|CLOOG\)\(LIBS\|INC\)/s:-[IL]/\(lib\|include\)::" \
    Makefile.orig > Makefile

Compile the package:

make AS_FOR_TARGET="${AS}" \
    LD_FOR_TARGET="${LD}"

Install the package:

make install

Details on this package are located in Section 10.16.2, “Contents of GCC.”