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Diffstat (limited to 'chapter06/readjusting.xml')
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1 files changed, 69 insertions, 66 deletions
diff --git a/chapter06/readjusting.xml b/chapter06/readjusting.xml index 18fc83d4a..e108286f0 100644 --- a/chapter06/readjusting.xml +++ b/chapter06/readjusting.xml @@ -1,113 +1,116 @@ <?xml version="1.0" encoding="ISO-8859-1"?> -<!DOCTYPE sect1 PUBLIC "-//OASIS//DTD DocBook XML V4.4//EN" "http://www.oasis-open.org/docbook/xml/4.4/docbookx.dtd" [ +<!DOCTYPE sect1 PUBLIC "-//OASIS//DTD DocBook XML V4.4//EN" + "http://www.oasis-open.org/docbook/xml/4.4/docbookx.dtd" [ <!ENTITY % general-entities SYSTEM "../general.ent"> %general-entities; ]> + <sect1 id="ch-system-readjusting"> -<title>Re-adjusting the Toolchain</title> -<?dbhtml filename="readjusting.html"?> - -<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/$(gcc -dumpmachine)/bin</filename>.</para> + <?dbhtml filename="readjusting.html"?> + + <title>Re-adjusting the Toolchain</title> + + <para>Now that the final C libraries have been installed, it is time to adjust + the toolchain again. The toolchain will be adjusted so that it will link any + newly compiled program against these new libraries. This is a similar process + used in the <quote>Adjusting</quote> phase in the beginning of <xref + linkend="chapter-temporary-tools"/>, but with the adjustments reversed. In <xref + linkend="chapter-temporary-tools"/>, the chain was guided from the host's + <filename class="directory">/{,usr/}lib</filename> directories to the new + <filename class="directory">/tools/lib</filename> directory. Now, the chain will + be guided from that same <filename class="directory">/tools/lib</filename> + directory to the LFS <filename class="directory">/{,usr/}lib</filename> + directories.</para> + + <para>First, backup the <filename class="directory">/tools</filename> linker, + and replace it with the adjusted linker we made in chapter 5. We'll also create + a link to its counterpart in <filename class="directory">/tools/$(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, and so that GCC knows where to find its start files. -A <command>perl</command> command accomplishes this:</para> + <para>Next, amend the GCC specs file so that it points to the new + dynamic linker, and so that GCC knows where to find its start files. + A <command>perl</command> command accomplishes this:</para> <screen><userinput>gcc -dumpspecs | \ perl -p -e 's@/tools/lib/ld-linux.so.2@/lib/ld-linux.so.2@g;' \ - -e 's@\*startfile_prefix_spec:\n@$_/usr/lib/ @g;' > \ - `dirname $(gcc --print-libgcc-file-name)`/specs -</userinput></screen> - -<para>It is a good idea to visually inspect the specs file to verify the intended -change was actually made.</para> - -<important><para>If working on a platform where the name of the -dynamic linker is something other than -<filename class="libraryfile">ld-linux.so.2</filename>, substitute -<quote>ld-linux.so.2</quote> with the name of the platform's -dynamic linker in the above commands. Refer back to <xref -linkend="ch-tools-toolchaintechnotes" role=","/> if -necessary.</para></important> - -<caution><para>It is imperative at this point to stop and ensure that -the basic functions (compiling and linking) of the adjusted toolchain -are working as expected. To do this, perform a sanity -check:</para> + -e 's@\*startfile_prefix_spec:\n@$_/usr/lib/ @g;' > \ + `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> + + <important> + <para>If working on a platform where the name of the dynamic linker is + something other than <filename class="libraryfile">ld-linux.so.2</filename>, + substitute <quote>ld-linux.so.2</quote> with the name of the platform's + dynamic linker in the above commands. Refer back to <xref + linkend="ch-tools-toolchaintechnotes" role=","/> if necessary.</para> + </important> + + <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. To do this, perform a sanity check:</para> <screen><userinput>echo 'main(){}' > dummy.c cc dummy.c -Wl,--verbose &> dummy.log 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 (allowing for -platform-specific differences in dynamic linker name):</para> + <para>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><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>Note that <filename class="directory">/lib</filename> is now + the prefix of our dynamic linker.</para> -<para>Now make sure that we're setup to use the correct start files:</para> + <para>Now make sure that we're setup to use the correct start files:</para> <screen><userinput>grep "/usr/lib/crt.* " dummy.log</userinput></screen> -<para>If everything is working correctly, there should be no errors, -and the output of the last command will be:</para> + <para>If everything is working correctly, there should be no errors, + and the output of the last command will be:</para> <screen><computeroutput>attempt to open /usr/lib/crt1.o succeeded attempt to open /usr/lib/crti.o succeeded attempt to open /usr/lib/crtn.o succeeded</computeroutput></screen> -<para>Next make sure that we're using the correct libc:</para> + <para>Next make sure that we're using the correct libc:</para> <screen><userinput>grep "/lib/libc.so.6 " dummy.log</userinput></screen> -<para>If everything is working correctly, there should be no errors, -and the output of the last command will be:</para> + <para>If everything is working correctly, there should be no errors, + and the output of the last command will be:</para> <screen><computeroutput>attempt to open /lib/libc.so.6 succeeded</computeroutput></screen> -<para>Lastly, make sure GCC is using the correct dynamic linker:</para> + <para>Lastly, make sure GCC is using the correct dynamic linker:</para> <screen><userinput>grep found dummy.log</userinput></screen> -<para>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> + <para>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><computeroutput>found ld-linux.so.2 at /lib/ld-linux.so.2</computeroutput></screen> -<para>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 amendment -above. Any issues will need to be resolved before continuing on with -the process.</para> + <para>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 amendment + above. Any issues will need to be resolved before continuing on with + the process.</para> -<para>Once everything is working correctly, clean up the test -files:</para> + <para>Once everything is working correctly, clean up the test + files:</para> -<screen><userinput>rm -v dummy.c a.out dummy.log</userinput></screen></caution> +<screen><userinput>rm -v dummy.c a.out dummy.log</userinput></screen> + </caution> </sect1> - |