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diff --git a/chapter06/adjustingtoolchain.xml b/chapter06/adjustingtoolchain.xml deleted file mode 100644 index a5606ad54..000000000 --- a/chapter06/adjustingtoolchain.xml +++ /dev/null @@ -1,96 +0,0 @@ -<sect1 id="ch06-adjustingtoolchain"> -<title>Re-adjusting the toolchain</title> -<?dbhtml filename="adjustingtoolchain.html" dir="chapter06"?> - -<para>Now that the new C libraries have been installed, it's time to re-adjust -our toolchain. We'll adjust it so that it will link any newly compiled program -against the new C libraries. Basically, this is the reverse of what we did -in the "locking in" stage in the beginning of the previous chapter.</para> - -<para>The first thing to do is to adjust the linker. For this we retained the -source and build directories from the second pass over Binutils. Install the -adjusted linker by running the following from within the -<filename class="directory">binutils-build</filename> directory:</para> - -<screen><userinput>make -C ld INSTALL=/tools/bin/install install</userinput></screen> - -<note><para>If you somehow missed the earlier warning to retain the Binutils -source and build directories from the second pass in Chapter 5 or otherwise -accidentally deleted them or just don't have access to them, don't worry, all is -not lost. Just ignore the above command. The result will be that the next -package, Binutils, will link against the Glibc libraries in -<filename class="directory">/tools</filename> rather than -<filename class="directory">/usr</filename>. This is not ideal, however, our -testing has shown that the resulting Binutils program binaries should be -identical.</para></note> - -<para>From now on every compiled program will link <emphasis>only</emphasis> -against the libraries in <filename>/usr/lib</filename> and -<filename>/lib</filename>. The extra -<userinput>INSTALL=/tools/bin/install</userinput> is needed because the Makefile -created during the second pass still contains the reference to -<filename>/usr/bin/install</filename>, which we obviously haven't installed yet. -Some host distributions contain a <filename class="symlink">ginstall</filename> -symbolic link which takes precedence in the Makefile and thus can cause a -problem here. The above command takes care of this also.</para> - -<para>You can now remove the Binutils source and build directories.</para> - -<para>The next thing to do is to amend our GCC specs file so that it points -to the new dynamic linker. Just like earlier on, we use a sed to accomplish -this:</para> - -<!-- Ampersands are needed to allow cut and paste --> - -<screen><userinput>SPECFILE=/tools/lib/gcc-lib/*/*/specs && -sed -e 's@ /tools/lib/ld-linux.so.2@ /lib/ld-linux.so.2@g' \ - $SPECFILE > newspecfile && -mv -f newspecfile $SPECFILE && -unset SPECFILE</userinput></screen> - -<para>Again, cutting and pasting the above is recommended. And just like -before, it is a good idea to check the specs file to ensure the intended -changes were actually made.</para> - -<important><para>If you are working on a platform where the name of the dynamic -linker is something other than <filename>ld-linux.so.2</filename>, you -<emphasis>must</emphasis> substitute <filename>ld-linux.so.2</filename> with the -name of your platform's dynamic linker in the above commands. Refer back to -<xref linkend="ch05-toolchaintechnotes"/> if necessary.</para></important> - -<!-- HACK - Force some whitespace to appease tidy --> -<literallayout></literallayout> - -<caution><para>It is imperative at this point to stop and ensure that the -basic functions (compiling and linking) of the adjusted toolchain are working -as expected. For this we are going to perform a simple sanity check:</para> - -<screen><userinput>echo 'main(){}' > dummy.c -gcc dummy.c -readelf -l a.out | grep ': /lib'</userinput></screen> - -<para>If everything is working correctly, there should be no errors, and the -output of the last command will be:</para> - -<blockquote><screen>[Requesting program interpreter: /lib/ld-linux.so.2]</screen></blockquote> - -<para>If you did not receive the output as shown above, or received no output at -all, then something is seriously wrong. You will need to investigate and retrace -your steps to find out where the problem is and correct it. There is no point in -continuing until this is done. Most likely something went wrong with the specs -file amendment above. Note especially that <filename>/lib</filename> now appears -as the prefix of our dynamic linker. Of course, if you are working on a platform -where the name of the dynamic linker is something other than -<filename>ld-linux.so.2</filename>, then the output will be slightly -different.</para> - -<para>Once you are satisfied that all is well, clean up the test files:</para> - -<screen><userinput>rm dummy.c a.out</userinput></screen> -</caution> - -<!-- HACK - Force some whitespace to appease tidy --> -<literallayout></literallayout> - -</sect1> - |