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diff --git a/chapter05/gcc-pass2-inst.xml b/chapter05/gcc-pass2-inst.xml deleted file mode 100644 index a5256c9ed..000000000 --- a/chapter05/gcc-pass2-inst.xml +++ /dev/null @@ -1,164 +0,0 @@ -<sect2><title> </title><para> </para></sect2> - -<sect2> -<title>Re-installation of GCC</title> - -<para>The tools required to test GCC and Binutils are installed now (Tcl, Expect -and DejaGnu). We can continue on rebuilding GCC and Binutils, link them against -the new Glibc, and test them properly. One thing to note, however, is that these -test suites are highly dependent on properly functioning pseudo terminals (PTYs) -which are provided by your host distribution. These days, PTYs are most commonly -implemented via the <emphasis>devpts</emphasis> file system. You can quickly -check if your host system is set up correctly in this regard by performing a -simple test:</para> - -<screen><userinput>expect -c "spawn ls"</userinput></screen> - -<para>If you receive the message:</para> - -<blockquote><screen>The system has no more ptys. Ask your system administrator to create more.</screen></blockquote> - -<para>Your host distribution is not set up for proper PTY operation. In this -case there is no point in running the test suites for GCC and Binutils until you -are able to resolve the issue. You can consult the LFS Wiki at -<ulink url="http://wiki.linuxfromscratch.org/"/> for more information on how to -get PTYs working.</para> - -<para>Unpack all three GCC tarballs (-core, -g++, and -testsuite) in one and the -same working directory. They will all unfold into a single -<filename>gcc-&gcc-version;/</filename> subdirectory.</para> - -<para>First correct one problem and make an essential adjustment:</para> - -<screen><userinput>patch -Np1 -i ../&gcc-nofixincludes-patch; -patch -Np1 -i ../&gcc-specs-patch;</userinput></screen> - -<para>The first patch disables the GCC "fixincludes" script. We mentioned this -briefly earlier, but a slightly more in-depth explanation of the fixincludes -process is warranted here. Under normal circumstances, the GCC fixincludes -script scans your system for header files that need to be fixed. It might find -that some Glibc header files on your host system need to be fixed, fix them and -put them in the GCC private include directory. Then, later on in -<xref linkend="chapter06"/>, after we've installed the newer Glibc, this -private include directory would be searched before the system include -directory, resulting in GCC finding the fixed headers from the host system, -which would most likely not match the Glibc version actually used for the LFS -system.</para> - -<para>The last patch changes GCC's default location of the dynamic linker -(typically <filename>ld-linux.so.2</filename>). It also removes -<filename class="directory">/usr/include</filename> from GCC's include search -path. Patching now rather than adjusting the specs file after installation -ensures that our new dynamic linker gets used during the actual build of GCC. -That is, all the final (and temporary) binaries created during the build will -link against the new Glibc.</para> - -<important><para>These patches are <emphasis>critical</emphasis> in ensuring a -successful overall build. Do not forget to apply them.</para></important> - -<para>Create a separate build directory again:</para> - -<screen><userinput>mkdir ../gcc-build -cd ../gcc-build</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 to be compiled:</para> - -<screen><userinput>../gcc-&gcc-version;/configure --prefix=/tools \ - --with-local-prefix=/tools \ - --enable-clocale=gnu --enable-shared \ - --enable-threads=posix --enable-__cxa_atexit \ - --enable-languages=c,c++</userinput></screen> - -<para>The meaning of the new configure options:</para> - -<itemizedlist> -<listitem><para><userinput>--enable-threads=posix</userinput>: This enables -C++ exception handling for multi-threaded code.</para></listitem> - -<listitem><para><userinput>--enable-__cxa_atexit</userinput>: This option -allows use of __cxa_atexit, rather than atexit, to register C++ destructors for -local statics and global objects and is essential for fully standards-compliant -handling of destructors. It also affects the C++ ABI and therefore results in -C++ shared libraries and C++ programs that are interoperable with other Linux -distributions.</para></listitem> - -<listitem><para><userinput>--enable-clocale=gnu</userinput>: This option ensures -the correct locale model is selected for the C++ libraries under all -circumstances. If the configure script finds the <emphasis>de_DE</emphasis> -locale installed, it will select the correct model of <emphasis>gnu</emphasis>. -However, people who don't install the <emphasis>de_DE</emphasis> locale, run the -risk of building ABI incompatible C++ libraries due to the wrong locale model of -<emphasis>generic</emphasis> being selected.</para></listitem> - -<listitem><para><userinput>--enable-languages=c,c++</userinput>: This option is -needed to ensure that both C and C++ compilers are built.</para></listitem> -</itemizedlist> - -<para>Compile the package:</para> - -<screen><userinput>make</userinput></screen> - -<para>There is no need to use the <userinput>bootstrap</userinput> target now, -as the compiler we're using to compile this GCC was built from the exact same -version of the GCC sources we used earlier.</para> - -<note><para>It's worth pointing out that running the GCC test suite here -is considered not as important as running it in -<xref linkend="chapter06"/>.</para></note> - -<para>Test the results:</para> - -<screen><userinput>make -k check</userinput></screen> - -<para>The <userinput>-k</userinput> 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. To get -a summary of the test suite results, run this:</para> - -<screen><userinput>../gcc-&gcc-version;/contrib/test_summary | more</userinput></screen> - -<para>You can compare your results to those posted to the gcc-testresults -mailing list for similar configurations to your own. For an example of how -current GCC-&gcc-version; should look on i686-pc-linux-gnu, see -<ulink url="http://gcc.gnu.org/ml/gcc-testresults/2003-08/msg01612.html"/>.</para> - -<para>Note that the results contain:</para> - -<screen>* 1 XPASS (unexpected pass) for g++ -* 1 FAIL (unexpected failure) for g++ -* 2 FAIL for gcc -* 26 XPASS's for libstdc++</screen> - -<para>The unexpected pass for g++ is due to the use of -<userinput>--enable-__cxa_atexit</userinput>. Apparently not all platforms -supported by GCC have support for "__cxa_atexit" in their C libraries, so this -test is not always expected to pass.</para> - -<para>The 26 unexpected passes for libstdc++ are due to the use of -<userinput>--enable-clocale=gnu</userinput>, which is the correct choice on -Glibc-based systems of versions 2.2.5 and above. The underlying locale support -in the GNU C library is superior to that of the otherwise selected "generic" -model (which may be applicable if for instance you were using Newlibc, Sun-libc -or whatever libc). The libstdc++ test suite is apparently expecting the -"generic" model, hence those tests are not always expected to pass.</para> - -<para>Unexpected failures often cannot be avoided. The GCC developers are -usually aware of them but haven't yet gotten around to fixing them. In short, -unless your results are vastly different from those at the above URL, it is safe -to continue on.</para> - -<para>And finally install the package:</para> - -<screen><userinput>make install</userinput></screen> - -<note><para>At this point it is strongly recommended to repeat the sanity check -we performed earlier in the chapter. Refer back to -<xref linkend="ch05-locking-glibc"/> and repeat the check. If the results are -wrong, then most likely you forgot to apply the above mentioned GCC Specs -patch.</para></note> - -</sect2> - |