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diff --git a/chapter06/readjusting.xml b/chapter06/readjusting.xml deleted file mode 100644 index 695a6d684..000000000 --- a/chapter06/readjusting.xml +++ /dev/null @@ -1,130 +0,0 @@ -<?xml version="1.0" encoding="ISO-8859-1"?> -<!DOCTYPE sect1 PUBLIC "-//OASIS//DTD DocBook XML V4.5//EN" - "http://www.oasis-open.org/docbook/xml/4.5/docbookx.dtd" [ - <!ENTITY % general-entities SYSTEM "../general.ent"> - %general-entities; -]> - -<sect1 id="ch-system-readjusting"> - <?dbhtml filename="readjusting.html"?> - - <title>Re-adjusting the Toolchain</title> - - <para>Now that the final C libraries have been installed, it is time to adjust - the toolchain again. The toolchain will be adjusted so that it will link any - newly compiled program against these new libraries. This is a similar process - used in the <quote>Adjusting</quote> phase in the beginning of <xref - linkend="chapter-temporary-tools"/>, but with the adjustments reversed. In <xref - linkend="chapter-temporary-tools"/>, the chain was guided from the host's - <filename class="directory">/{,usr/}lib</filename> directories to the new - <filename class="directory">/tools/lib</filename> directory. Now, the chain will - be guided from that same <filename class="directory">/tools/lib</filename> - directory to the LFS <filename class="directory">/{,usr/}lib</filename> - directories.</para> - - <para>First, backup the <filename class="directory">/tools</filename> linker, - and replace it with the adjusted linker we made in chapter 5. We'll also create - a link to its counterpart in <filename class="directory">/tools/$(gcc - -dumpmachine)/bin</filename>:</para> - -<screen><userinput>mv -v /tools/bin/{ld,ld-old} -mv -v /tools/$(gcc -dumpmachine)/bin/{ld,ld-old} -mv -v /tools/bin/{ld-new,ld} -ln -sv /tools/bin/ld /tools/$(gcc -dumpmachine)/bin/ld</userinput></screen> - - <para>Next, amend the GCC specs file so that it points to the new - dynamic linker. Simply deleting all instances of <quote>/tools</quote> should - leave us with the correct path to the dynamic linker. Also adjust the specs file - so that GCC knows where to find the correct headers and Glibc start files. - A <command>sed</command> command accomplishes this:</para> - -<screen><userinput>gcc -dumpspecs | sed -e 's@/tools@@g' \ - -e '/\*startfile_prefix_spec:/{n;s@.*@/usr/lib/ @}' \ - -e '/\*cpp:/{n;s@$@ -isystem /usr/include@}' > \ - `dirname $(gcc --print-libgcc-file-name)`/specs</userinput></screen> - - <para>It is a good idea to visually inspect the specs file to verify the - intended change was actually made.</para> - - <para>It is imperative at this point to ensure that the basic - functions (compiling and linking) of the adjusted toolchain are working - as expected. To do this, perform the following sanity checks:</para> - -<screen os="a"><userinput>echo 'main(){}' > dummy.c -cc dummy.c -v -Wl,--verbose &> dummy.log -readelf -l a.out | grep ': /lib'</userinput></screen> - - <para os="b">If everything is working correctly, there should be no errors, - and the output of the last command will be (allowing for - platform-specific differences in dynamic linker name):</para> - -<screen os="c"><computeroutput>[Requesting program interpreter: /lib/ld-linux.so.2]</computeroutput></screen> - - <para>Note that <filename class="directory">/lib</filename> is now - the prefix of our dynamic linker.</para> - - <para os="d">Now make sure that we're setup to use the correct startfiles:</para> - -<screen os="e"><userinput>grep -o '/usr/lib.*/crt[1in].*succeeded' dummy.log</userinput></screen> - - <para os="f">If everything is working correctly, there should be no errors, - and the output of the last command will be:</para> - -<screen><computeroutput>/usr/lib/crt1.o succeeded -/usr/lib/crti.o succeeded -/usr/lib/crtn.o succeeded</computeroutput></screen> - - <para os="g">Verify that the compiler is searching for the correct header - files:</para> - -<screen><userinput>grep -B1 '^ /usr/include' dummy.log</userinput></screen> - - <para os="h">This command should return successfully with the following output:</para> - -<screen><computeroutput>#include <...> search starts here: - /usr/include</computeroutput></screen> - - <para os="i">Next, verify that the new linker is being used with the correct search paths:</para> - -<screen os="j"><userinput>grep 'SEARCH.*/usr/lib' dummy.log |sed 's|; |\n|g'</userinput></screen> - - <para os="k">If everything is working correctly, there should be no errors, - and the output of the last command (allowing for platform-specific target triplets) - will be:</para> - -<screen><computeroutput>SEARCH_DIR("/tools/i686-pc-linux-gnu/lib") -SEARCH_DIR("/usr/lib") -SEARCH_DIR("/lib");</computeroutput></screen> - - <para os="l">Next make sure that we're using the correct libc:</para> - -<screen os="m"><userinput>grep "/lib.*/libc.so.6 " dummy.log</userinput></screen> - - <para os="n">If everything is working correctly, there should be no errors, - and the output of the last command (allowing for a lib64 directory on 64-bit hosts) - will be:</para> - -<screen os="o"><computeroutput>attempt to open /lib/libc.so.6 succeeded</computeroutput></screen> - - <para os="p">Lastly, make sure GCC is using the correct dynamic linker:</para> - -<screen os="q"><userinput>grep found dummy.log</userinput></screen> - - <para os="r">If everything is working correctly, there should be no errors, - and the output of the last command will be (allowing for - platform-specific differences in dynamic linker name and a lib64 directory - on 64-bit hosts):</para> - -<screen os="s"><computeroutput>found ld-linux.so.2 at /lib/ld-linux.so.2</computeroutput></screen> - - <para os="t">If the output does not appear as shown above or is not received - at all, then something is seriously wrong. Investigate and retrace the - steps to find out where the problem is and correct it. The most likely - reason is that something went wrong with the specs file adjustment. Any - issues will need to be resolved before continuing on with the process.</para> - - <para os="u">Once everything is working correctly, clean up the test files:</para> - -<screen os="v"><userinput>rm -v dummy.c a.out dummy.log</userinput></screen> - -</sect1> |