Changeset ad2c960 for chapter06/readjusting.xml
- Timestamp:
- 02/07/2006 07:43:36 PM (19 years ago)
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- ae20451
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- bdb61fa
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chapter06/readjusting.xml
rbdb61fa rad2c960 1 1 <?xml version="1.0" encoding="ISO-8859-1"?> 2 <!DOCTYPE sect1 PUBLIC "-//OASIS//DTD DocBook XML V4.4//EN" "http://www.oasis-open.org/docbook/xml/4.4/docbookx.dtd" [ 2 <!DOCTYPE sect1 PUBLIC "-//OASIS//DTD DocBook XML V4.4//EN" 3 "http://www.oasis-open.org/docbook/xml/4.4/docbookx.dtd" [ 3 4 <!ENTITY % general-entities SYSTEM "../general.ent"> 4 5 %general-entities; 5 6 ]> 7 6 8 <sect1 id="ch-system-readjusting"> 7 <title>Re-adjusting the Toolchain</title> 8 <?dbhtml filename="readjusting.html"?> 9 <?dbhtml filename="readjusting.html"?> 9 10 10 <para>Now that the final C libraries have been installed, it is time to adjust 11 the toolchain again. The toolchain will be adjusted so that it will link any 12 newly compiled program against these new libraries. This is a similar process 13 used in the <quote>Adjusting</quote> phase in the beginning of <xref 14 linkend="chapter-temporary-tools"/>, but with the adjustments reversed. In <xref 15 linkend="chapter-temporary-tools"/>, the chain was guided from the host's 16 <filename class="directory">/{,usr/}lib</filename> directories to the new 17 <filename class="directory">/tools/lib</filename> directory. Now, the chain will 18 be guided from that same <filename class="directory">/tools/lib</filename> 19 directory to the LFS <filename class="directory">/{,usr/}lib</filename> 20 directories.</para> 11 <title>Re-adjusting the Toolchain</title> 21 12 22 <para>First, backup the <filename class="directory">/tools</filename> linker, and 23 replace it with the adjusted linker we made in chapter 5. We'll also create a 24 link to its counterpart in <filename class="directory">/tools/$(gcc -dumpmachine)/bin</filename>.</para> 13 <para>Now that the final C libraries have been installed, it is time to adjust 14 the toolchain again. The toolchain will be adjusted so that it will link any 15 newly compiled program against these new libraries. This is a similar process 16 used in the <quote>Adjusting</quote> phase in the beginning of <xref 17 linkend="chapter-temporary-tools"/>, but with the adjustments reversed. In <xref 18 linkend="chapter-temporary-tools"/>, the chain was guided from the host's 19 <filename class="directory">/{,usr/}lib</filename> directories to the new 20 <filename class="directory">/tools/lib</filename> directory. Now, the chain will 21 be guided from that same <filename class="directory">/tools/lib</filename> 22 directory to the LFS <filename class="directory">/{,usr/}lib</filename> 23 directories.</para> 24 25 <para>First, backup the <filename class="directory">/tools</filename> linker, 26 and replace it with the adjusted linker we made in chapter 5. We'll also create 27 a link to its counterpart in <filename class="directory">/tools/$(gcc 28 -dumpmachine)/bin</filename>.</para> 25 29 26 30 <screen><userinput>mv -v /tools/bin/{ld,ld-old} … … 29 33 ln -sv /tools/bin/ld /tools/$(gcc -dumpmachine)/bin/ld</userinput></screen> 30 34 31 <para>Next, amend the GCC specs file so that it points to the new32 dynamic linker, and so that GCC knows where to find its start files.33 A <command>perl</command> command accomplishes this:</para>35 <para>Next, amend the GCC specs file so that it points to the new 36 dynamic linker, and so that GCC knows where to find its start files. 37 A <command>perl</command> command accomplishes this:</para> 34 38 35 39 <screen><userinput>gcc -dumpspecs | \ 36 40 perl -p -e 's@/tools/lib/ld-linux.so.2@/lib/ld-linux.so.2@g;' \ 37 -e 's@\*startfile_prefix_spec:\n@$_/usr/lib/ @g;' > \ 38 `dirname $(gcc --print-libgcc-file-name)`/specs 39 </userinput></screen> 41 -e 's@\*startfile_prefix_spec:\n@$_/usr/lib/ @g;' > \ 42 `dirname $(gcc --print-libgcc-file-name)`/specs</userinput></screen> 40 43 41 <para>It is a good idea to visually inspect the specs file to verify the intended 42 change was actually made.</para>44 <para>It is a good idea to visually inspect the specs file to verify the 45 intended change was actually made.</para> 43 46 44 <important><para>If working on a platform where the name of the 45 dynamic linker is something other than 46 <filename class="libraryfile">ld-linux.so.2</filename>, substitute 47 <quote>ld-linux.so.2</quote> with the name of the platform's48 dynamic linker in the above commands. Refer back to <xref49 linkend="ch-tools-toolchaintechnotes" role=","/> if 50 necessary.</para></important>47 <important> 48 <para>If working on a platform where the name of the dynamic linker is 49 something other than <filename class="libraryfile">ld-linux.so.2</filename>, 50 substitute <quote>ld-linux.so.2</quote> with the name of the platform's 51 dynamic linker in the above commands. Refer back to <xref 52 linkend="ch-tools-toolchaintechnotes" role=","/> if necessary.</para> 53 </important> 51 54 52 <caution><para>It is imperative at this point to stop and ensure that 53 the basic functions (compiling and linking) of the adjusted toolchain 54 are working as expected. To do this, perform a sanity 55 check:</para>55 <caution> 56 <para>It is imperative at this point to stop and ensure that the basic 57 functions (compiling and linking) of the adjusted toolchain are working 58 as expected. To do this, perform a sanity check:</para> 56 59 57 60 <screen><userinput>echo 'main(){}' > dummy.c … … 59 62 readelf -l a.out | grep ': /lib'</userinput></screen> 60 63 61 <para>If everything is working correctly, there should be no errors,62 and the output of the last command will be (allowing for63 platform-specific differences in dynamic linker name):</para>64 <para>If everything is working correctly, there should be no errors, 65 and the output of the last command will be (allowing for 66 platform-specific differences in dynamic linker name):</para> 64 67 65 68 <screen><computeroutput>[Requesting program interpreter: /lib/ld-linux.so.2]</computeroutput></screen> 66 69 67 <para>Note that <filename class="directory">/lib</filename> is now68 the prefix of our dynamic linker.</para>70 <para>Note that <filename class="directory">/lib</filename> is now 71 the prefix of our dynamic linker.</para> 69 72 70 <para>Now make sure that we're setup to use the correct start files:</para>73 <para>Now make sure that we're setup to use the correct start files:</para> 71 74 72 75 <screen><userinput>grep "/usr/lib/crt.* " dummy.log</userinput></screen> 73 76 74 <para>If everything is working correctly, there should be no errors,75 and the output of the last command will be:</para>77 <para>If everything is working correctly, there should be no errors, 78 and the output of the last command will be:</para> 76 79 77 80 <screen><computeroutput>attempt to open /usr/lib/crt1.o succeeded … … 79 82 attempt to open /usr/lib/crtn.o succeeded</computeroutput></screen> 80 83 81 <para>Next make sure that we're using the correct libc:</para>84 <para>Next make sure that we're using the correct libc:</para> 82 85 83 86 <screen><userinput>grep "/lib/libc.so.6 " dummy.log</userinput></screen> 84 87 85 <para>If everything is working correctly, there should be no errors,86 and the output of the last command will be:</para>88 <para>If everything is working correctly, there should be no errors, 89 and the output of the last command will be:</para> 87 90 88 91 <screen><computeroutput>attempt to open /lib/libc.so.6 succeeded</computeroutput></screen> 89 92 90 <para>Lastly, make sure GCC is using the correct dynamic linker:</para>93 <para>Lastly, make sure GCC is using the correct dynamic linker:</para> 91 94 92 95 <screen><userinput>grep found dummy.log</userinput></screen> 93 96 94 <para>If everything is working correctly, there should be no errors,95 and the output of the last command will be (allowing for96 platform-specific differences in dynamic linker name):</para>97 <para>If everything is working correctly, there should be no errors, 98 and the output of the last command will be (allowing for 99 platform-specific differences in dynamic linker name):</para> 97 100 98 101 <screen><computeroutput>found ld-linux.so.2 at /lib/ld-linux.so.2</computeroutput></screen> 99 102 100 <para>If the output does not appear as shown above or is not received101 at all, then something is seriously wrong. Investigate and retrace the102 steps to find out where the problem is and correct it. The most likely103 reason is that something went wrong with the specs file amendment104 above. Any issues will need to be resolved before continuing on with105 the process.</para>103 <para>If the output does not appear as shown above or is not received 104 at all, then something is seriously wrong. Investigate and retrace the 105 steps to find out where the problem is and correct it. The most likely 106 reason is that something went wrong with the specs file amendment 107 above. Any issues will need to be resolved before continuing on with 108 the process.</para> 106 109 107 <para>Once everything is working correctly, clean up the test108 files:</para>110 <para>Once everything is working correctly, clean up the test 111 files:</para> 109 112 110 <screen><userinput>rm -v dummy.c a.out dummy.log</userinput></screen></caution> 113 <screen><userinput>rm -v dummy.c a.out dummy.log</userinput></screen> 114 </caution> 111 115 112 116 </sect1> 113
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