%general-entities; ]> GCC This package is known to have issues when its default optimization flags (including the -march and -mcpu options) are changed. If any environment variables that override default optimizations have been defined, such as CFLAGS and CXXFLAGS, unset them when building GCC. Unpack both the gcc-core and the gcc-g++ tarballs—they will unpack into the same directory. Likewise, extract the gcc-testsuite package. Apply only the No-Fixincludes patch (not the Specs patch) also used in the previous chapter: patch -Np1 -i ../gcc-&gcc-version;-no_fixincludes-1.patch GCC fails to compile some packages outside of a base Linux From Scratch install (e.g., Mozilla and kdegraphics) when used in conjunction with newer versions of Binutils. Apply the following patch to fix this issue: patch -Np1 -i ../gcc-&gcc-version;-linkonce-1.patch Apply a sed substitution that will suppress the installation of libiberty.a. The version of libiberty.a provided by Binutils will be used instead: sed -i 's/install_to_$(INSTALL_DEST) //' libiberty/Makefile.in The GCC documentation recommends building GCC outside of the source directory in a dedicated build directory: mkdir ../gcc-build cd ../gcc-build Prepare GCC for compilation: ../gcc-&gcc-version;/configure --prefix=/usr \ --libexecdir=/usr/lib --enable-shared \ --enable-threads=posix --enable-__cxa_atexit \ --enable-clocale=gnu --enable-languages=c,c++ Compile the package: make In this section, the test suite for GCC is considered critical. Do not skip it under any circumstance. Test the results, but do not stop at errors: make -k check Some of the errors are known issues and were noted in the previous chapter. The test suite notes from are still relevant here. Be sure to refer back to them as necessary. Install the package: make install Some packages expect the C PreProcessor to be installed in the /lib directory. To support those packages, create this symlink: ln -s ../usr/bin/cpp /lib Many packages use the name cc to call the C compiler. To satisfy those packages, create a symlink: ln -s gcc /usr/bin/cc At this point, it is strongly recommended to repeat the sanity check performed earlier in this chapter. Refer back to and repeat the check. If the results are in error, then the most likely reason is that the GCC Specs patch from was erroneously applied here. Installed programs Installed libraries c++, cc (link to gcc), cpp, g++, gcc, gccbug, and gcov libgcc.a, libgcc_eh.a, libgcc_s.so, libstdc++.[a,so], and libsupc++.a Short Descriptions cc The C compiler cc cpp The C preprocessor; it is used by the compiler to expand the #include, #define, and similar statements in the source files cpp c++ The C++ compiler c++ g++ The C++ compiler g++ gcc The C compiler gcc gccbug A shell script used to help create useful bug reports gccbug gcov A coverage testing tool; it is used to analyze programs to determine where optimizations will have the most effect gcov libgcc Contains run-time support for gcc libgcc* libstdc++ The standard C++ library libstdc++ libsupc++ Provides supporting routines for the C++ programming language libsupc++