Update to libcap-2.28.
[linux_from_scratch.git] / chapter06 / gcc.xml
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1 <?xml version="1.0" encoding="ISO-8859-1"?>
2 <!DOCTYPE sect1 PUBLIC "-//OASIS//DTD DocBook XML V4.5//EN"
3   "http://www.oasis-open.org/docbook/xml/4.5/docbookx.dtd" [
4   <!ENTITY % general-entities SYSTEM "../general.ent">
5   %general-entities;
6 ]>
8 <sect1 id="ch-system-gcc" role="wrap">
9   <?dbhtml filename="gcc.html"?>
11   <sect1info condition="script">
12     <productname>gcc</productname>
13     <productnumber>&gcc-version;</productnumber>
14     <address>&gcc-url;</address>
15   </sect1info>
17   <title>GCC-&gcc-version;</title>
19   <indexterm zone="ch-system-gcc">
20     <primary sortas="a-GCC">GCC</primary>
21   </indexterm>
23   <sect2 role="package">
24     <title/>
26     <para>The GCC package contains the GNU compiler collection, which includes
27     the C and C++ compilers.</para>
29     <segmentedlist>
30       <segtitle>&buildtime;</segtitle>
31       <segtitle>&diskspace;</segtitle>
33       <seglistitem>
34         <seg>&gcc-ch6-sbu;</seg>
35         <seg>&gcc-ch6-du;</seg>
36       </seglistitem>
37     </segmentedlist>
39   </sect2>
41   <sect2 role="installation">
42     <title>Installation of GCC</title>
44     <para>If building on x86_64, change the default directory name for 64-bit
45     libraries to <quote>lib</quote>:</para>
47 <screen><userinput remap="pre">case $(uname -m) in
48   x86_64)
49     sed -e '/m64=/s/lib64/lib/' \
50         -i.orig gcc/config/i386/t-linux64
51   ;;
52 esac</userinput></screen>
54     <para>The GCC documentation recommends building GCC in a dedicated build directory:</para>
56 <screen><userinput remap="pre">mkdir -v build
57 cd       build</userinput></screen>
59     <para>Prepare GCC for compilation:</para>
61 <screen><userinput remap="configure">SED=sed                               \
62 ../configure --prefix=/usr            \
63              --enable-languages=c,c++ \
64              --disable-multilib       \
65              --disable-bootstrap      \
66              --with-system-zlib</userinput></screen>
68     <para>Note that for other languages, there are some prerequisites that
69     are not yet available. See the
70     <ulink url="&blfs-book;general/gcc.html">BLFS Book</ulink>
71     for instructions on how to build all of GCC's supported languages.</para>
73     <variablelist>
74       <title>The meaning of the new configure parameters:</title>
76       <varlistentry>
77         <term><envar>SED=sed</envar></term>
78         <listitem>
79           <para>Setting this environment variable prevents a hard-coded
80           path to /tools/bin/sed.</para>
81         </listitem>
82       </varlistentry>
83       <!-- 
84       <varlistentry>
85         <term><parameter>- -disable-libmpx</parameter></term>
86         <listitem>
87           <para>This switch tells GCC to not build mpx (Memory Protection
88           Extensions) that can cause problems on some processors. It has
89           been removed from the next version of gcc.</para>
90         </listitem>
91       </varlistentry>
92       -->
93       <varlistentry>
94         <term><parameter>--with-system-zlib</parameter></term>
95         <listitem>
96           <para>This switch tells GCC to link to the system installed copy of
97           the Zlib library, rather than its own internal copy.</para>
98         </listitem>
99       </varlistentry>
100     </variablelist>
102     <para>Compile the package:</para>
104 <screen><userinput remap="make">make</userinput></screen>
106     <important>
107       <para>In this section, the test suite for GCC is considered
108       critical. Do not skip it under any circumstance.</para>
109     </important>
111    <para>One set of tests in the GCC test suite is known to exhaust the stack,
112    so increase the stack size prior to running the tests:</para>
114 <screen><userinput remap="test">ulimit -s 32768</userinput></screen>
116     <para>Test the results as a non-privileged user, but do not stop at errors:</para>
118 <screen><userinput remap="test">chown -Rv nobody . 
119 su nobody -s /bin/bash -c "PATH=$PATH make -k check"</userinput></screen>
121     <para>To receive a summary of the test suite results, run:</para>
123 <screen><userinput remap="test">../contrib/test_summary</userinput></screen>
125     <para>For only the summaries, pipe the output through
126     <userinput>grep -A7 Summ</userinput>.</para>
128     <para>Results can be compared with those located at <ulink
129     url="&test-results;"/> and
130     <ulink url="https://gcc.gnu.org/ml/gcc-testresults/"/>.</para>
132     <para>Six tests related to get_time are known to fail.  These are
133     apparently related to the en_HK locale.</para>
135     <para>Two tests named lookup.cc and reverse.cc in experimental/net
136     are known to fail in LFS chroot environment because they require
137     /etc/hosts and iana-etc.</para>
139     <para>Two tests named pr57193.c and pr90178.c are known to fail.</para>
141     <para>A few unexpected failures cannot always be avoided. The GCC developers
142     are usually aware of these issues, but have not resolved them yet.
143     Unless the test results are vastly different from those at the above URL,
144     it is safe to continue.</para>
146     <!--note><para>
147       On some combinations of kernel configuration and AMD processors
148       there may be more than 1100 failures in the gcc.target/i386/mpx
149       tests (which are designed to test the MPX option on recent
150       Intel processors). These can safely be ignored on AMD
151       processors. These tests will also fail on Intel processors if MPX support
152       is not enabled in the kernel even though it is present on the CPU.
153     </para></note-->
155     <para>Install the package and remove an unneeded directory:</para>
157 <screen><userinput remap="install">make install
158 rm -rf /usr/lib/gcc/$(gcc -dumpmachine)/&gcc-version;/include-fixed/bits/</userinput></screen>
160     <para>The GCC build directory is owned by <systemitem class="username">
161     nobody</systemitem> now and the ownership of the installed header
162     directory (and its content) will be incorrect.  Change the ownership to
163     <systemitem class="username">root</systemitem> user and group:</para>
165 <screen><userinput remap="install">chown -v -R root:root \
166     /usr/lib/gcc/*linux-gnu/&gcc-version;/include{,-fixed}</userinput></screen>
168     <para>Create a symlink required by the <ulink
169     url="https://refspecs.linuxfoundation.org/FHS_3.0/fhs/ch03s09.html">FHS</ulink>
170     for "historical" reasons.</para>
172 <screen><userinput remap="install">ln -sv ../usr/bin/cpp /lib</userinput></screen>
174     <para>Many packages use the name <command>cc</command> to call the C
175     compiler. To satisfy those packages, create a symlink:</para>
177 <screen><userinput remap="install">ln -sv gcc /usr/bin/cc</userinput></screen>
179     <para>Add a compatibility symlink to enable building programs with
180     Link Time Optimization (LTO):</para> 
182 <screen><userinput remap="install">install -v -dm755 /usr/lib/bfd-plugins
183 ln -sfv ../../libexec/gcc/$(gcc -dumpmachine)/&gcc-version;/liblto_plugin.so \
184         /usr/lib/bfd-plugins/</userinput></screen>
186     <para>Now that our final toolchain is in place, it is important to again ensure
187     that compiling and linking will work as expected. We do this by performing
188     the same sanity checks as we did earlier in the chapter:</para>
190     <xi:include xmlns:xi="http://www.w3.org/2001/XInclude"
191     href="adjusting.xml"
192     xpointer="xpointer(//*[@os='a'])"/>
194     <xi:include xmlns:xi="http://www.w3.org/2001/XInclude"
195     href="adjusting.xml"
196     xpointer="xpointer(//*[@os='b'])"/>
198     <xi:include xmlns:xi="http://www.w3.org/2001/XInclude"
199     href="adjusting.xml"
200     xpointer="xpointer(//*[@os='c'])"/>
202     <xi:include xmlns:xi="http://www.w3.org/2001/XInclude"
203     href="adjusting.xml"
204     xpointer="xpointer(//*[@os='d'])"/>
206     <xi:include xmlns:xi="http://www.w3.org/2001/XInclude"
207     href="adjusting.xml"
208     xpointer="xpointer(//*[@os='e'])"/>
210     <xi:include xmlns:xi="http://www.w3.org/2001/XInclude"
211     href="adjusting.xml"
212     xpointer="xpointer(//*[@os='f'])"/>
214 <screen><computeroutput>/usr/lib/gcc/x86_64-pc-linux-gnu/&gcc-version;/../../../../lib/crt1.o succeeded
215 /usr/lib/gcc/x86_64-pc-linux-gnu/&gcc-version;/../../../../lib/crti.o succeeded
216 /usr/lib/gcc/x86_64-pc-linux-gnu/&gcc-version;/../../../../lib/crtn.o succeeded</computeroutput></screen>
218   <para>Depending on your machine architecture, the above may differ slightly,
219   the difference usually being the name of the directory
220   after <filename class="directory">/usr/lib/gcc</filename>. The important
221   thing to look for here is that <command>gcc</command> has found all three
222   <filename>crt*.o</filename> files under the
223   <filename class="directory">/usr/lib</filename> directory.</para>
225     <xi:include xmlns:xi="http://www.w3.org/2001/XInclude"
226     href="adjusting.xml"
227     xpointer="xpointer(//*[@os='g'])"/>
229 <screen><userinput>grep -B4 '^ /usr/include' dummy.log</userinput></screen>
231     <xi:include xmlns:xi="http://www.w3.org/2001/XInclude"
232     href="adjusting.xml"
233     xpointer="xpointer(//*[@os='h'])"/>
235 <screen><computeroutput>#include &lt;...&gt; search starts here:
236  /usr/lib/gcc/x86_64-pc-linux-gnu/&gcc-version;/include
237  /usr/local/include
238  /usr/lib/gcc/x86_64-pc-linux-gnu/&gcc-version;/include-fixed
239  /usr/include</computeroutput></screen>
241    <para>Again, note that the directory named after your target triplet may be
242    different than the above, depending on your architecture.</para>
244 <!--  This appears to be obsolete
246     <note><para>As of version 4.3.0, GCC now unconditionally installs the
247     <filename>limits.h</filename> file into the private
248     <filename class="directory">include-fixed</filename> directory, and that
249     directory is required to be in place.</para></note>
252     <xi:include xmlns:xi="http://www.w3.org/2001/XInclude"
253     href="adjusting.xml"
254     xpointer="xpointer(//*[@os='i'])"/>
256     <xi:include xmlns:xi="http://www.w3.org/2001/XInclude"
257     href="adjusting.xml"
258     xpointer="xpointer(//*[@os='j'])"/>
260     <xi:include xmlns:xi="http://www.w3.org/2001/XInclude"
261     href="adjusting.xml"
262     xpointer="xpointer(//*[@os='k'])"/>
264 <screen><computeroutput>SEARCH_DIR("/usr/x86_64-pc-linux-gnu/lib64")
265 SEARCH_DIR("/usr/local/lib64")
266 SEARCH_DIR("/lib64")
267 SEARCH_DIR("/usr/lib64")
268 SEARCH_DIR("/usr/x86_64-pc-linux-gnu/lib")
269 SEARCH_DIR("/usr/local/lib")
270 SEARCH_DIR("/lib")
271 SEARCH_DIR("/usr/lib");</computeroutput></screen>
273    <para>A 32-bit system may see a few different directories. For example, here
274    is the output from an i686 machine:</para>
276 <screen><computeroutput>SEARCH_DIR("/usr/i686-pc-linux-gnu/lib32")
277 SEARCH_DIR("/usr/local/lib32")
278 SEARCH_DIR("/lib32")
279 SEARCH_DIR("/usr/lib32")
280 SEARCH_DIR("/usr/i686-pc-linux-gnu/lib")
281 SEARCH_DIR("/usr/local/lib")
282 SEARCH_DIR("/lib")
283 SEARCH_DIR("/usr/lib");</computeroutput></screen>
285     <xi:include xmlns:xi="http://www.w3.org/2001/XInclude"
286     href="adjusting.xml"
287     xpointer="xpointer(//*[@os='l'])"/>
289     <xi:include xmlns:xi="http://www.w3.org/2001/XInclude"
290     href="adjusting.xml"
291     xpointer="xpointer(//*[@os='m'])"/>
293     <xi:include xmlns:xi="http://www.w3.org/2001/XInclude"
294     href="adjusting.xml"
295     xpointer="xpointer(//*[@os='n'])"/>
297     <xi:include xmlns:xi="http://www.w3.org/2001/XInclude"
298     href="adjusting.xml"
299     xpointer="xpointer(//*[@os='o'])"/>
301     <xi:include xmlns:xi="http://www.w3.org/2001/XInclude"
302     href="adjusting.xml"
303     xpointer="xpointer(//*[@os='p'])"/>
305     <xi:include xmlns:xi="http://www.w3.org/2001/XInclude"
306     href="adjusting.xml"
307     xpointer="xpointer(//*[@os='q'])"/>
309     <xi:include xmlns:xi="http://www.w3.org/2001/XInclude"
310     href="adjusting.xml"
311     xpointer="xpointer(//*[@os='r'])"/>
313     <xi:include xmlns:xi="http://www.w3.org/2001/XInclude"
314     href="adjusting.xml"
315     xpointer="xpointer(//*[@os='s'])"/>
317     <xi:include xmlns:xi="http://www.w3.org/2001/XInclude"
318     href="adjusting.xml"
319     xpointer="xpointer(//*[@os='t'])"/>
321     <xi:include xmlns:xi="http://www.w3.org/2001/XInclude"
322     href="adjusting.xml"
323     xpointer="xpointer(//*[@os='u'])"/>
325     <xi:include xmlns:xi="http://www.w3.org/2001/XInclude"
326     href="adjusting.xml"
327     xpointer="xpointer(//*[@os='v'])"/>
329     <para>Finally, move a misplaced file:</para>
331 <screen><userinput remap="install">mkdir -pv /usr/share/gdb/auto-load/usr/lib
332 mv -v /usr/lib/*gdb.py /usr/share/gdb/auto-load/usr/lib</userinput></screen>
334   </sect2>
336   <sect2 id="contents-gcc" role="content">
337     <title>Contents of GCC</title>
339     <segmentedlist>
340       <segtitle>Installed programs</segtitle>
341       <segtitle>Installed libraries</segtitle>
342       <segtitle>Installed directories</segtitle>
344       <seglistitem>
345         <seg>c++, cc (link to gcc), cpp, g++, gcc,
346         gcc-ar, gcc-nm, gcc-ranlib, gcov, gcov-dump, and gcov-tool</seg>
348         <seg>libasan.{a,so}, libatomic.{a,so}, libcc1.so, libgcc.a, libgcc_eh.a,
349         libgcc_s.so, libgcov.a, libgomp.{a,so}, libitm.{a,so},
350         liblsan.{a,so}, liblto_plugin.so,
351         libquadmath.{a,so}, libssp.{a,so}, libssp_nonshared.a,
352         libstdc++.{a,so}, libstdc++fs.a, libsupc++.a, libtsan.{a,so},
353         and libubsan.{a,so}</seg>
355         <seg>/usr/include/c++, /usr/lib/gcc, /usr/libexec/gcc, and 
356         /usr/share/gcc-&gcc-version;</seg>
357       </seglistitem>
358     </segmentedlist>
360     <variablelist>
361       <bridgehead renderas="sect3">Short Descriptions</bridgehead>
362       <?dbfo list-presentation="list"?>
363       <?dbhtml list-presentation="table"?>
365       <varlistentry id="c">
366         <term><command>c++</command></term>
367         <listitem>
368           <para>The C++ compiler</para>
369           <indexterm zone="ch-system-gcc c">
370             <primary sortas="b-c++">c++</primary>
371           </indexterm>
372         </listitem>
373       </varlistentry>
375       <varlistentry id="cc">
376         <term><command>cc</command></term>
377         <listitem>
378           <para>The C compiler</para>
379           <indexterm zone="ch-system-gcc cc">
380             <primary sortas="b-cc">cc</primary>
381           </indexterm>
382         </listitem>
383       </varlistentry>
385       <varlistentry id="cpp">
386         <term><command>cpp</command></term>
387         <listitem>
388           <para>The C preprocessor; it is used by the compiler to expand the
389           #include, #define, and similar statements in the source files</para>
390           <indexterm zone="ch-system-gcc cpp">
391             <primary sortas="b-cpp">cpp</primary>
392           </indexterm>
393         </listitem>
394       </varlistentry>
396       <varlistentry id="g">
397         <term><command>g++</command></term>
398         <listitem>
399           <para>The C++ compiler</para>
400           <indexterm zone="ch-system-gcc g">
401             <primary sortas="b-g++">g++</primary>
402           </indexterm>
403         </listitem>
404       </varlistentry>
406       <varlistentry id="gcc">
407         <term><command>gcc</command></term>
408         <listitem>
409           <para>The C compiler</para>
410           <indexterm zone="ch-system-gcc gcc">
411             <primary sortas="b-gcc">gcc</primary>
412           </indexterm>
413         </listitem>
414       </varlistentry>
416       <varlistentry id="gcc-ar">
417         <term><command>gcc-ar</command></term>
418         <listitem>
419           <para>A wrapper around <command>ar</command> that adds a
420           plugin to the command line. This program is only used
421           to add "link time optimization" and is not useful with the
422           default build options</para>
423           <indexterm zone="ch-system-gcc gcc-ar">
424             <primary sortas="b-gcc-ar">gc-ar</primary>
425           </indexterm>
426         </listitem>
427       </varlistentry>
429       <varlistentry id="gcc-nm">
430         <term><command>gcc-nm</command></term>
431         <listitem>
432           <para>A wrapper around <command>nm</command> that adds a
433           plugin to the command line. This program is only used
434           to add "link time optimization" and is not useful with the
435           default build options</para>
436           <indexterm zone="ch-system-gcc gcc-nm">
437             <primary sortas="b-gcc-nm">gc-nm</primary>
438           </indexterm>
439         </listitem>
440       </varlistentry>
442       <varlistentry id="gcc-ranlib">
443         <term><command>gcc-ranlib</command></term>
444         <listitem>
445           <para>A wrapper around <command>ranlib</command> that adds a
446           plugin to the command line. This program is only used
447           to add "link time optimization" and is not useful with the
448           default build options</para>
449           <indexterm zone="ch-system-gcc gcc-ranlib">
450             <primary sortas="b-gcc-ranlib">gc-ranlib</primary>
451           </indexterm>
452         </listitem>
453       </varlistentry>
455       <varlistentry id="gcov">
456         <term><command>gcov</command></term>
457         <listitem>
458           <para>A coverage testing tool; it is used to analyze programs to
459           determine where optimizations will have the most effect</para>
460           <indexterm zone="ch-system-gcc gcov">
461             <primary sortas="b-gcov">gcov</primary>
462           </indexterm>
463         </listitem>
464       </varlistentry>
466       <varlistentry id="gcov-dump">
467         <term><command>gcov-dump</command></term>
468         <listitem>
469           <para>Offline gcda and gcno profile dump tool</para>
470           <indexterm zone="ch-system-gcc gcov-dump">
471             <primary sortas="b-gcov-dump">gcov-dump</primary>
472           </indexterm>
473         </listitem>
474       </varlistentry>
476       <varlistentry id="gcov-tool">
477         <term><command>gcov-tool</command></term>
478         <listitem>
479           <para>Offline gcda profile processing tool</para>
480           <indexterm zone="ch-system-gcc gcov-tool">
481             <primary sortas="b-gcov-tool">gcov-tool</primary>
482           </indexterm>
483         </listitem>
484       </varlistentry>
486       <varlistentry id="libasan">
487         <term><filename class="libraryfile">libasan</filename></term>
488         <listitem>
489           <para>The Address Sanitizer runtime library</para>
490           <indexterm zone="ch-system-gcc libasan">
491             <primary sortas="b-libasan">libasan</primary>
492           </indexterm>
493         </listitem>
494       </varlistentry>
496       <varlistentry id="libatomic">
497         <term><filename class="libraryfile">libatomic</filename></term>
498         <listitem>
499           <para>GCC atomic built-in runtime library</para>
500           <indexterm zone="ch-system-gcc libatomic">
501             <primary sortas="b-libatomic">libatomic</primary>
502           </indexterm>
503         </listitem>
504       </varlistentry>
506       <varlistentry id="libcc1">
507         <term><filename class="libraryfile">libcc1</filename></term>
508         <listitem>
509           <para>The C preprocessing library</para>
510           <indexterm zone="ch-system-gcc libcc1">
511             <primary sortas="b-libcc1">libcc1</primary>
512           </indexterm>
513         </listitem>
514       </varlistentry>
516       <varlistentry id="libgcc">
517         <term><filename class="libraryfile">libgcc</filename></term>
518         <listitem>
519           <para>Contains run-time support for <command>gcc</command></para>
520           <indexterm zone="ch-system-gcc libgcc">
521             <primary sortas="c-libgcc">libgcc</primary>
522           </indexterm>
523         </listitem>
524       </varlistentry>
526       <varlistentry id="libgcov">
527         <term><filename class="libraryfile">libgcov</filename></term>
528         <listitem>
529           <para>This library is linked in to a program when GCC is instructed
530           to enable profiling</para>
531           <indexterm zone="ch-system-gcc libgcov">
532             <primary sortas="c-libgcov">libgcov</primary>
533           </indexterm>
534         </listitem>
535       </varlistentry>
537       <varlistentry id="libgomp">
538         <term><filename class="libraryfile">libgomp</filename></term>
539         <listitem>
540           <para>GNU implementation of the OpenMP API for multi-platform
541           shared-memory parallel programming in C/C++ and Fortran</para>
542           <indexterm zone="ch-system-gcc libgomp">
543             <primary sortas="c-libgomp">libgomp</primary>
544           </indexterm>
545         </listitem>
546       </varlistentry>
548       <varlistentry id="liblsan">
549         <term><filename class="libraryfile">liblsan</filename></term>
550         <listitem>
551           <para>The Leak Sanitizer runtime library</para>
552           <indexterm zone="ch-system-gcc liblsan">
553             <primary sortas="c-liblsan">liblsan</primary>
554           </indexterm>
555         </listitem>
556       </varlistentry>
558       <varlistentry id="liblto_plugin">
559         <term><filename class="libraryfile">liblto_plugin</filename></term>
560         <listitem>
561           <para>GCC's Link Time Optimization (LTO) plugin allows GCC to perform
562           optimizations across compilation units</para>
563           <indexterm zone="ch-system-gcc liblto_plugin">
564             <primary sortas="c-liblto_plugin">liblto_plugin</primary>
565           </indexterm>
566         </listitem>
567       </varlistentry>
569       <varlistentry id="libquadmath">
570         <term><filename class="libraryfile">libquadmath</filename></term>
571         <listitem>
572           <para>GCC Quad Precision Math Library API</para>
573           <indexterm zone="ch-system-gcc libquadmath">
574             <primary sortas="c-libquadmath">libquadmath</primary>
575           </indexterm>
576         </listitem>
577       </varlistentry>
579       <varlistentry id="libssp">
580         <term><filename class="libraryfile">libssp</filename></term>
581         <listitem>
582           <para>Contains routines supporting GCC's stack-smashing protection
583           functionality</para>
584           <indexterm zone="ch-system-gcc libssp">
585             <primary sortas="c-libssp">libssp</primary>
586           </indexterm>
587         </listitem>
588       </varlistentry>
590       <varlistentry id="libstdc">
591         <term><filename class="libraryfile">libstdc++</filename></term>
592         <listitem>
593           <para>The standard C++ library</para>
594           <indexterm zone="ch-system-gcc libstdc">
595             <primary sortas="c-libstdc++">libstdc++</primary>
596           </indexterm>
597         </listitem>
598       </varlistentry>
600       <varlistentry id="libstdcfs">
601         <term><filename class="libraryfile">libstdc++fs</filename></term>
602         <listitem>
603           <para>ISO/IEC TS 18822:2015 Filesystem library</para>
604           <indexterm zone="ch-system-gcc libstdcfs">
605             <primary sortas="c-libstdc++fs">libstdc++fs</primary>
606           </indexterm>
607         </listitem>
608       </varlistentry>
610       <varlistentry id="libsupc">
611         <term><filename class="libraryfile">libsupc++</filename></term>
612         <listitem>
613           <para>Provides supporting routines for the C++ programming
614           language</para>
615           <indexterm zone="ch-system-gcc libsupc">
616             <primary sortas="c-libsupc++">libsupc++</primary>
617           </indexterm>
618         </listitem>
619       </varlistentry>
621       <varlistentry id="libtsan">
622         <term><filename class="libraryfile">libtsan</filename></term>
623         <listitem>
624           <para>The Thread Sanitizer runtime library</para>
625           <indexterm zone="ch-system-gcc libtsan">
626             <primary sortas="c-libtsan">libtsan</primary>
627           </indexterm>
628         </listitem>
629       </varlistentry>
631       <varlistentry id="libubsan">
632         <term><filename class="libraryfile">libubsan</filename></term>
633         <listitem>
634           <para>The Undefined Behavior Sanitizer runtime library</para>
635           <indexterm zone="ch-system-gcc libubsan">
636             <primary sortas="c-libubsan">libubsan</primary>
637           </indexterm>
638         </listitem>
639       </varlistentry>
641     </variablelist>
643   </sect2>
645 </sect1>