5.11. GCC-4.1.2 - Pass 2

5.11.1. Re-installation of GCC

The tools required to test GCC and Binutils—Tcl, Expect and DejaGNU—are installed now. GCC and Binutils can now be rebuilt, linking them against the new Glibc and testing them properly (if running the test suites in this chapter). Please note that these test suites are highly dependent on properly functioning PTYs which are provided by the host. PTYs are most commonly implemented via the devpts file system. Check to see if the host system is set up correctly in this regard by performing a quick test:

expect -c "spawn ls"

The response might be:

The system has no more ptys.
Ask your system administrator to create more.

If the above message is received, the host does not have its PTYs set up properly. In this case, there is no point in running the test suites for GCC and Binutils until this issue is resolved. Please consult the LFS FAQ at http://www.linuxfromscratch.org//lfs/faq.html#no-ptys for more information on how to get PTYs working.

As previously explained in Section 5.7, “Adjusting the Toolchain”, under normal circumstances the GCC fixincludes script is run in order to fix potentially broken header files. As GCC-4.1.2 and Glibc-2.5.1 have already been installed at this point, and their respective header files are known to not require fixing, the fixincludes script is not required. As mentioned previously, the script may in fact pollute the build environment by installing fixed headers from the host system into GCC's private include directory. The running of the fixincludes script can be suppressed by issuing the following commands:

cp -v gcc/Makefile.in{,.orig}
sed 's@\./fixinc\.sh@-c true@' gcc/Makefile.in.orig > gcc/Makefile.in

The bootstrap build performed in Section 5.4, “GCC-4.1.2 - Pass 1” built GCC with the -fomit-frame-pointer compiler flag. Non-bootstrap builds omit this flag by default, so apply the following sed to use it in order to ensure consistent compiler builds:

cp -v gcc/Makefile.in{,.tmp}
sed 's/^XCFLAGS =$/& -fomit-frame-pointer/' gcc/Makefile.in.tmp \
  > gcc/Makefile.in

Apply the following patch to change the location of GCC's default dynamic linker (typically ld-linux.so.2):

patch -Np1 -i ../gcc-4.1.2-specs-1.patch

The above patch also removes /usr/include from GCC's include search path. Patching now rather than adjusting the specs file after installation ensures that the new dynamic linker is used during the actual build of GCC. That is, all of the binaries created during the build will link against the new Glibc.

Create a separate build directory again:

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

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

Now prepare GCC for compilation:

../gcc-4.1.2/configure --prefix=/tools \
    --with-local-prefix=/tools --enable-clocale=gnu \
    --enable-shared --enable-threads=posix \
    --enable-__cxa_atexit --enable-languages=c,c++ \
    --disable-libstdcxx-pch

Compile the package:

make

There is no need to use the bootstrap target now because the compiler being used to compile this GCC was built from the exact same version of the GCC sources used earlier.

Compilation is now complete. As previously mentioned, running the test suites for the temporary tools compiled in this chapter is not mandatory. To run the GCC test suite anyway, use the following command:

make -k check

The -k flag is used to make the test suite run through to completion and not stop at the first failure. The GCC test suite is very comprehensive and is almost guaranteed to generate a few failures.

For a discussion of test failures that are of particular importance, please see Section 6.12, “GCC-4.1.2.”

Install the package:

make install