source: chapter08/gcc.xml@ 753d2cd

arm
Last change on this file since 753d2cd was 753d2cd, checked in by William Harrington <kb0iic@…>, 2 years ago

gcc-12: remove unnecessary workaround for PR91085

Reference: https://gcc.gnu.org/r12-1924

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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]>
7
8<sect1 id="ch-system-gcc" role="wrap">
9 <?dbhtml filename="gcc.html"?>
10
11 <sect1info condition="script">
12 <productname>gcc</productname>
13 <productnumber>&gcc-version;</productnumber>
14 <address>&gcc-url;</address>
15 </sect1info>
16
17 <title>GCC-&gcc-version;</title>
18
19 <indexterm zone="ch-system-gcc">
20 <primary sortas="a-GCC">GCC</primary>
21 </indexterm>
22
23 <sect2 role="package">
24 <title/>
25
26 <para>The GCC package contains the GNU compiler collection, which includes
27 the C and C++ compilers.</para>
28
29 <segmentedlist>
30 <segtitle>&buildtime;</segtitle>
31 <segtitle>&diskspace;</segtitle>
32
33 <seglistitem>
34 <seg>&gcc-fin-sbu;</seg>
35 <seg>&gcc-fin-du;</seg>
36 </seglistitem>
37 </segmentedlist>
38
39 </sect2>
40
41 <sect2 role="installation">
42 <title>Installation of GCC</title>
43<!--
44 <para>At first, fix an issue breaking
45 <filename class="libraryfile">libasan.a</filename> building this package
46 with Glibc-2.34 or later:</para>
47
48<screen><userinput remap="pre">sed -e '/static.*SIGSTKSZ/d' \
49 -e 's/return kAltStackSize/return SIGSTKSZ * 4/' \
50 -i libsanitizer/sanitizer_common/sanitizer_posix_libcdep.cpp</userinput></screen>
51-->
52 <para>If building on aarch64, change the default directory name for 64-bit
53 libraries to <quote>lib</quote>:</para>
54
55<screen><userinput remap="pre">case $(uname -m) in
56 aarch64)
57 sed -e '/mabi.lp64=/s/lib64/lib/' \
58 -i.orig gcc/config/aarch64/t-aarch64-linux
59 ;;
60esac</userinput></screen>
61
62 <para>The GCC documentation recommends building GCC in a dedicated build directory:</para>
63
64<screen><userinput remap="pre">mkdir -v build
65cd build</userinput></screen>
66
67 <para>Prepare GCC for compilation:</para>
68
69<screen><userinput remap="configure">../configure --prefix=/usr \
70 LD=ld \
71 --enable-languages=c,c++ \
72 --disable-multilib \
73 --disable-bootstrap \
74 --with-system-zlib</userinput></screen>
75
76 <para>Note that for other programming languages there are some prerequisites that
77 are not yet available. See the
78 <ulink url="&blfs-book;general/gcc.html">BLFS Book GCC page</ulink>
79 for instructions on how to build all of GCC's supported languages.</para>
80
81 <variablelist>
82 <title>The meaning of the new configure parameters:</title>
83
84 <varlistentry>
85 <term><parameter>LD=ld</parameter></term>
86 <listitem>
87 <para>This parameter makes the configure script use the ld installed
88 by the binutils built earlier in this chapter, rather than
89 the cross-built version which would otherwise be used.</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>
101
102 <para>Compile the package:</para>
103
104<screen><userinput remap="make">make</userinput></screen>
105
106 <important>
107 <para>In this section, the test suite for GCC is considered
108 important, but it takes a long time. First time builders are
109 encouraged to not skip it. The time to run the tests can be
110 reduced significantly by adding -jx to the make command below
111 where x is the number of cores on your system.</para>
112 </important>
113
114 <para>One set of tests in the GCC test suite is known to exhaust the default
115 stack, so increase the stack size prior to running the tests:</para>
116
117<screen><userinput remap="test">ulimit -s 32768</userinput></screen>
118
119 <para>Test the results as a non-privileged user, but do not stop at errors:</para>
120
121<screen><userinput remap="test">chown -Rv tester .
122su tester -c "PATH=$PATH make -k check"</userinput></screen>
123
124 <para>To receive a summary of the test suite results, run:</para>
125
126<screen><userinput remap="test">../contrib/test_summary</userinput></screen>
127
128 <para>For only the summaries, pipe the output through
129 <userinput>grep -A7 Summ</userinput>.</para>
130
131 <para>Results can be compared with those located at <ulink
132 url="&test-results;"/> and
133 <ulink url="https://gcc.gnu.org/ml/gcc-testresults/"/>.</para>
134
135 <!-- https://gcc.gnu.org/bugzilla/show_bug.cgi?id=101081 -->
136 <para>Eight tests related to analyzer are known to fail.</para>
137
138 <para>In libstdc++, one numpunct test and six tests related to get_time are
139 known to fail. These are all because the locale definitions in glibc have
140 changed but libstdc++ does not currently support those changes.</para>
141
142 <para>A few unexpected failures cannot always be avoided. The GCC developers
143 are usually aware of these issues, but have not resolved them yet.
144 Unless the test results are vastly different from those at the above URL,
145 it is safe to continue.</para>
146
147 <!--note><para>
148 On some combinations of kernel configuration and AMD processors
149 there may be more than 1100 failures in the gcc.target/i386/mpx
150 tests (which are designed to test the MPX option on recent
151 Intel processors). These can safely be ignored on AMD
152 processors. These tests will also fail on Intel processors if MPX support
153 is not enabled in the kernel even though it is present on the CPU.
154 </para></note-->
155
156 <para>Install the package:</para>
157
158<screen><userinput remap="install">make install</userinput></screen>
159
160 <para>The GCC build directory is owned by <systemitem class="username">
161 tester</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>
164
165<screen><userinput remap="install">chown -v -R root:root \
166 /usr/lib/gcc/$(gcc -dumpmachine)/&gcc-version;/include{,-fixed}</userinput></screen>
167
168 <para>Create a symlink required by the <ulink
169 url="https://refspecs.linuxfoundation.org/FHS_3.0/fhs/ch03s09.html">FHS</ulink>
170 for "historical" reasons.</para>
171
172<screen><userinput remap="install">ln -svr /usr/bin/cpp /usr/lib</userinput></screen>
173 <!-- already done earlier
174 <para>Many packages use the name <command>cc</command> to call the C
175 compiler. To satisfy those packages, create a symlink:</para>
176
177<screen><userinput remap="install">ln -sv gcc /usr/bin/cc</userinput></screen>
178 -->
179 <para>Add a compatibility symlink to enable building programs with
180 Link Time Optimization (LTO):</para>
181
182<screen><userinput remap="install">ln -sfv ../../libexec/gcc/$(gcc -dumpmachine)/&gcc-version;/liblto_plugin.so \
183 /usr/lib/bfd-plugins/</userinput></screen>
184
185 <para>Now that our final toolchain is in place, it is important to again ensure
186 that compiling and linking will work as expected. We do this by performing
187 some sanity checks:</para>
188
189<screen><userinput>echo 'int main(){}' &gt; dummy.c
190cc dummy.c -v -Wl,--verbose &amp;&gt; dummy.log
191readelf -l a.out | grep ': /lib'</userinput></screen>
192
193 <para>There should be no errors,
194 and the output of the last command will be (allowing for
195 platform-specific differences in the dynamic linker name):</para>
196
197<screen><computeroutput>[Requesting program interpreter: /lib64/ld-linux-aarch64.so.1]</computeroutput></screen>
198
199 <para>Now make sure that we're setup to use the correct start files:</para>
200
201<screen><userinput>grep -o '/usr/lib.*/crt[1in].*succeeded' dummy.log</userinput></screen>
202
203 <para>The output of the last command should be:</para>
204
205<screen><computeroutput>/usr/lib/gcc/aarch64-unknown-linux-gnu/&gcc-version;/../../../../lib/crt1.o succeeded
206/usr/lib/gcc/aarch64-unknown-linux-gnu/&gcc-version;/../../../../lib/crti.o succeeded
207/usr/lib/gcc/aarch64-unknown-linux-gnu/&gcc-version;/../../../../lib/crtn.o succeeded</computeroutput></screen>
208
209 <para>Depending on your machine architecture, the above may differ slightly.
210 The difference will be the name of the directory
211 after <filename class="directory">/usr/lib/gcc</filename>. The important
212 thing to look for here is that <command>gcc</command> has found all three
213 <filename>crt*.o</filename> files under the
214 <filename class="directory">/usr/lib</filename> directory.</para>
215
216 <para>Verify that the compiler is searching for the correct header
217 files:</para>
218
219<screen><userinput>grep -B4 '^ /usr/include' dummy.log</userinput></screen>
220
221 <para>This command should return the following output:</para>
222
223<screen><computeroutput>#include &lt;...&gt; search starts here:
224 /usr/lib/gcc/aarch64-unknown-linux-gnu/&gcc-version;/include
225 /usr/local/include
226 /usr/lib/gcc/aarch64-unknown-linux-gnu/&gcc-version;/include-fixed
227 /usr/include</computeroutput></screen>
228
229 <para>Again, the directory named after your target triplet may be
230 different than the above, depending on your system architecture.</para>
231
232 <para>Next, verify that the new linker is being used with the correct search paths:</para>
233
234<screen><userinput>grep 'SEARCH.*/usr/lib' dummy.log |sed 's|; |\n|g'</userinput></screen>
235
236 <para>References to paths that have components with '-linux-gnu' should
237 be ignored, but otherwise the output of the last command should be:</para>
238
239<screen><computeroutput>SEARCH_DIR("/usr/aarch64-unknown-linux-gnu/lib64")
240SEARCH_DIR("/usr/local/lib64")
241SEARCH_DIR("/lib64")
242SEARCH_DIR("/usr/lib64")
243SEARCH_DIR("/usr/aarch64-unknown-linux-gnu/lib")
244SEARCH_DIR("/usr/local/lib")
245SEARCH_DIR("/lib")
246SEARCH_DIR("/usr/lib");</computeroutput></screen>
247
248 <para>A 32-bit system may see a few different directories. For example, here
249 is the output from a 32bit ARM machine:</para>
250
251<screen><computeroutput>SEARCH_DIR("/usr/armv6l-unknown-linux-gnueabihf/lib")
252SEARCH_DIR("/usr/local/lib")
253SEARCH_DIR("/lib")
254SEARCH_DIR("/usr/lib");</computeroutput></screen>
255
256 <para>Next make sure that we're using the correct libc:</para>
257
258<screen><userinput>grep "/lib.*/libc.so.6 " dummy.log</userinput></screen>
259
260 <para>The output of the last command should be:</para>
261
262<screen><computeroutput>attempt to open /usr/lib/libc.so.6 succeeded</computeroutput></screen>
263
264 <para>Make sure GCC is using the correct dynamic linker:</para>
265
266<screen><userinput>grep found dummy.log</userinput></screen>
267
268 <para>The output of the last command should be (allowing for
269 platform-specific differences in dynamic linker name):</para>
270
271<screen><computeroutput>found ld-linux-aarch64.so.1 at /usr/lib/ld-linux-aarch64.so.1</computeroutput></screen>
272
273 <para>If the output does not appear as shown above or is not received
274 at all, then something is seriously wrong. Investigate and retrace the
275 steps to find out where the problem is and correct it. <!--The most likely
276 reason is that something went wrong with the specs file adjustment.--> Any
277 issues will need to be resolved before continuing with the process.</para>
278
279 <para>Once everything is working correctly, clean up the test files:</para>
280
281<screen><userinput>rm -v dummy.c a.out dummy.log</userinput></screen>
282
283 <para>Finally, move a misplaced file:</para>
284
285<screen><userinput remap="install">mkdir -pv /usr/share/gdb/auto-load/usr/lib
286mv -v /usr/lib/*gdb.py /usr/share/gdb/auto-load/usr/lib</userinput></screen>
287
288 </sect2>
289
290 <sect2 id="contents-gcc" role="content">
291 <title>Contents of GCC</title>
292
293 <segmentedlist>
294 <segtitle>Installed programs</segtitle>
295 <segtitle>Installed libraries</segtitle>
296 <segtitle>Installed directories</segtitle>
297
298 <seglistitem>
299 <seg>c++, cc (link to gcc), cpp, g++, gcc,
300 gcc-ar, gcc-nm, gcc-ranlib, gcov, gcov-dump, gcov-tool,
301 and lto-dump</seg>
302
303 <seg>libasan.{a,so}, libatomic.{a,so}, libcc1.so, libgcc.a, libgcc_eh.a,
304 libgcc_s.so, libgcov.a, libgomp.{a,so}, libitm.{a,so},
305 liblsan.{a,so}, liblto_plugin.so,
306 libssp.{a,so}, libssp_nonshared.a,
307 libstdc++.{a,so}, libstdc++fs.a, libsupc++.a, libtsan.{a,so},
308 and libubsan.{a,so}</seg>
309
310 <seg>/usr/include/c++, /usr/lib/gcc, /usr/libexec/gcc, and
311 /usr/share/gcc-&gcc-version;</seg>
312 </seglistitem>
313 </segmentedlist>
314
315 <variablelist>
316 <bridgehead renderas="sect3">Short Descriptions</bridgehead>
317 <?dbfo list-presentation="list"?>
318 <?dbhtml list-presentation="table"?>
319
320 <varlistentry id="c">
321 <term><command>c++</command></term>
322 <listitem>
323 <para>The C++ compiler</para>
324 <indexterm zone="ch-system-gcc c">
325 <primary sortas="b-c++">c++</primary>
326 </indexterm>
327 </listitem>
328 </varlistentry>
329
330 <varlistentry id="cc">
331 <term><command>cc</command></term>
332 <listitem>
333 <para>The C compiler</para>
334 <indexterm zone="ch-system-gcc cc">
335 <primary sortas="b-cc">cc</primary>
336 </indexterm>
337 </listitem>
338 </varlistentry>
339
340 <varlistentry id="cpp">
341 <term><command>cpp</command></term>
342 <listitem>
343 <para>The C preprocessor; it is used by the compiler to expand the
344 #include, #define, and similar statements in the source files</para>
345 <indexterm zone="ch-system-gcc cpp">
346 <primary sortas="b-cpp">cpp</primary>
347 </indexterm>
348 </listitem>
349 </varlistentry>
350
351 <varlistentry id="g">
352 <term><command>g++</command></term>
353 <listitem>
354 <para>The C++ compiler</para>
355 <indexterm zone="ch-system-gcc g">
356 <primary sortas="b-g++">g++</primary>
357 </indexterm>
358 </listitem>
359 </varlistentry>
360
361 <varlistentry id="gcc">
362 <term><command>gcc</command></term>
363 <listitem>
364 <para>The C compiler</para>
365 <indexterm zone="ch-system-gcc gcc">
366 <primary sortas="b-gcc">gcc</primary>
367 </indexterm>
368 </listitem>
369 </varlistentry>
370
371 <varlistentry id="gcc-ar">
372 <term><command>gcc-ar</command></term>
373 <listitem>
374 <para>A wrapper around <command>ar</command> that adds a
375 plugin to the command line. This program is only used
376 to add "link time optimization" and is not useful with the
377 default build options</para>
378 <indexterm zone="ch-system-gcc gcc-ar">
379 <primary sortas="b-gcc-ar">gc-ar</primary>
380 </indexterm>
381 </listitem>
382 </varlistentry>
383
384 <varlistentry id="gcc-nm">
385 <term><command>gcc-nm</command></term>
386 <listitem>
387 <para>A wrapper around <command>nm</command> that adds a
388 plugin to the command line. This program is only used
389 to add "link time optimization" and is not useful with the
390 default build options</para>
391 <indexterm zone="ch-system-gcc gcc-nm">
392 <primary sortas="b-gcc-nm">gc-nm</primary>
393 </indexterm>
394 </listitem>
395 </varlistentry>
396
397 <varlistentry id="gcc-ranlib">
398 <term><command>gcc-ranlib</command></term>
399 <listitem>
400 <para>A wrapper around <command>ranlib</command> that adds a
401 plugin to the command line. This program is only used
402 to add "link time optimization" and is not useful with the
403 default build options</para>
404 <indexterm zone="ch-system-gcc gcc-ranlib">
405 <primary sortas="b-gcc-ranlib">gc-ranlib</primary>
406 </indexterm>
407 </listitem>
408 </varlistentry>
409
410 <varlistentry id="gcov">
411 <term><command>gcov</command></term>
412 <listitem>
413 <para>A coverage testing tool; it is used to analyze programs to
414 determine where optimizations will have the most effect</para>
415 <indexterm zone="ch-system-gcc gcov">
416 <primary sortas="b-gcov">gcov</primary>
417 </indexterm>
418 </listitem>
419 </varlistentry>
420
421 <varlistentry id="gcov-dump">
422 <term><command>gcov-dump</command></term>
423 <listitem>
424 <para>Offline gcda and gcno profile dump tool</para>
425 <indexterm zone="ch-system-gcc gcov-dump">
426 <primary sortas="b-gcov-dump">gcov-dump</primary>
427 </indexterm>
428 </listitem>
429 </varlistentry>
430
431 <varlistentry id="gcov-tool">
432 <term><command>gcov-tool</command></term>
433 <listitem>
434 <para>Offline gcda profile processing tool</para>
435 <indexterm zone="ch-system-gcc gcov-tool">
436 <primary sortas="b-gcov-tool">gcov-tool</primary>
437 </indexterm>
438 </listitem>
439 </varlistentry>
440
441 <varlistentry id="lto-dump">
442 <term><command>lto-dump</command></term>
443 <listitem>
444 <para>Tool for dumping object files produced by GCC with LTO
445 enabled</para>
446 <indexterm zone="ch-system-gcc lto-dump">
447 <primary sortas="b-lto-dump">lto-dump</primary>
448 </indexterm>
449 </listitem>
450 </varlistentry>
451
452 <varlistentry id="libasan">
453 <term><filename class="libraryfile">libasan</filename></term>
454 <listitem>
455 <para>The Address Sanitizer runtime library</para>
456 <indexterm zone="ch-system-gcc libasan">
457 <primary sortas="b-libasan">libasan</primary>
458 </indexterm>
459 </listitem>
460 </varlistentry>
461
462 <varlistentry id="libatomic">
463 <term><filename class="libraryfile">libatomic</filename></term>
464 <listitem>
465 <para>GCC atomic built-in runtime library</para>
466 <indexterm zone="ch-system-gcc libatomic">
467 <primary sortas="b-libatomic">libatomic</primary>
468 </indexterm>
469 </listitem>
470 </varlistentry>
471
472 <varlistentry id="libcc1">
473 <term><filename class="libraryfile">libcc1</filename></term>
474 <listitem>
475 <para>The C preprocessing library</para>
476 <indexterm zone="ch-system-gcc libcc1">
477 <primary sortas="b-libcc1">libcc1</primary>
478 </indexterm>
479 </listitem>
480 </varlistentry>
481
482 <varlistentry id="libgcc">
483 <term><filename class="libraryfile">libgcc</filename></term>
484 <listitem>
485 <para>Contains run-time support for <command>gcc</command></para>
486 <indexterm zone="ch-system-gcc libgcc">
487 <primary sortas="c-libgcc">libgcc</primary>
488 </indexterm>
489 </listitem>
490 </varlistentry>
491
492 <varlistentry id="libgcov">
493 <term><filename class="libraryfile">libgcov</filename></term>
494 <listitem>
495 <para>This library is linked in to a program when GCC is instructed
496 to enable profiling</para>
497 <indexterm zone="ch-system-gcc libgcov">
498 <primary sortas="c-libgcov">libgcov</primary>
499 </indexterm>
500 </listitem>
501 </varlistentry>
502
503 <varlistentry id="libgomp">
504 <term><filename class="libraryfile">libgomp</filename></term>
505 <listitem>
506 <para>GNU implementation of the OpenMP API for multi-platform
507 shared-memory parallel programming in C/C++ and Fortran</para>
508 <indexterm zone="ch-system-gcc libgomp">
509 <primary sortas="c-libgomp">libgomp</primary>
510 </indexterm>
511 </listitem>
512 </varlistentry>
513
514 <varlistentry id="libitm">
515 <term><filename class="libraryfile">libitm</filename></term>
516 <listitem>
517 <para>The GNU transactional memory library</para>
518 <indexterm zone="ch-system-gcc libitm">
519 <primary sortas="c-libitm">libitm</primary>
520 </indexterm>
521 </listitem>
522 </varlistentry>
523
524 <varlistentry id="liblsan">
525 <term><filename class="libraryfile">liblsan</filename></term>
526 <listitem>
527 <para>The Leak Sanitizer runtime library</para>
528 <indexterm zone="ch-system-gcc liblsan">
529 <primary sortas="c-liblsan">liblsan</primary>
530 </indexterm>
531 </listitem>
532 </varlistentry>
533
534 <varlistentry id="liblto_plugin">
535 <term><filename class="libraryfile">liblto_plugin</filename></term>
536 <listitem>
537 <para>GCC's LTO plugin allows binutils to process object files
538 produced by GCC with LTO enabled</para>
539 <indexterm zone="ch-system-gcc liblto_plugin">
540 <primary sortas="c-liblto_plugin">liblto_plugin</primary>
541 </indexterm>
542 </listitem>
543 </varlistentry>
544
545 <varlistentry id="libquadmath">
546 <term><filename class="libraryfile">libquadmath</filename></term>
547 <listitem>
548 <para>GCC Quad Precision Math Library API</para>
549 <indexterm zone="ch-system-gcc libquadmath">
550 <primary sortas="c-libquadmath">libquadmath</primary>
551 </indexterm>
552 </listitem>
553 </varlistentry>
554
555 <varlistentry id="libssp">
556 <term><filename class="libraryfile">libssp</filename></term>
557 <listitem>
558 <para>Contains routines supporting GCC's stack-smashing protection
559 functionality</para>
560 <indexterm zone="ch-system-gcc libssp">
561 <primary sortas="c-libssp">libssp</primary>
562 </indexterm>
563 </listitem>
564 </varlistentry>
565
566 <varlistentry id="libstdc">
567 <term><filename class="libraryfile">libstdc++</filename></term>
568 <listitem>
569 <para>The standard C++ library</para>
570 <indexterm zone="ch-system-gcc libstdc">
571 <primary sortas="c-libstdc++">libstdc++</primary>
572 </indexterm>
573 </listitem>
574 </varlistentry>
575
576 <varlistentry id="libstdcfs">
577 <term><filename class="libraryfile">libstdc++fs</filename></term>
578 <listitem>
579 <para>ISO/IEC TS 18822:2015 Filesystem library</para>
580 <indexterm zone="ch-system-gcc libstdcfs">
581 <primary sortas="c-libstdc++fs">libstdc++fs</primary>
582 </indexterm>
583 </listitem>
584 </varlistentry>
585
586 <varlistentry id="libsupc">
587 <term><filename class="libraryfile">libsupc++</filename></term>
588 <listitem>
589 <para>Provides supporting routines for the C++ programming
590 language</para>
591 <indexterm zone="ch-system-gcc libsupc">
592 <primary sortas="c-libsupc++">libsupc++</primary>
593 </indexterm>
594 </listitem>
595 </varlistentry>
596
597 <varlistentry id="libtsan">
598 <term><filename class="libraryfile">libtsan</filename></term>
599 <listitem>
600 <para>The Thread Sanitizer runtime library</para>
601 <indexterm zone="ch-system-gcc libtsan">
602 <primary sortas="c-libtsan">libtsan</primary>
603 </indexterm>
604 </listitem>
605 </varlistentry>
606
607 <varlistentry id="libubsan">
608 <term><filename class="libraryfile">libubsan</filename></term>
609 <listitem>
610 <para>The Undefined Behavior Sanitizer runtime library</para>
611 <indexterm zone="ch-system-gcc libubsan">
612 <primary sortas="c-libubsan">libubsan</primary>
613 </indexterm>
614 </listitem>
615 </varlistentry>
616
617 </variablelist>
618
619 </sect2>
620
621</sect1>
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