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30<h1>Installing GCC: Old documentation</h1>
31<h1 align="center">Old installation documentation</h1>
32
33<p>Note most of this information is out of date and superseded by the
34previous chapters of this manual.  It is provided for historical
35reference only, because of a lack of volunteers to merge it into the
36main manual.
37
38<p>Here is the procedure for installing GNU CC on a GNU or Unix system. 
39See <a href="#VMS%20Install">VMS Install</a>, for VMS systems.
40
41<ol type=1 start=1>
42</p><li>If you have chosen a configuration for GNU CC which requires other GNU
43tools (such as GAS or the GNU linker) instead of the standard system
44tools, install the required tools in the build directory under the names
45<code>as</code>, <code>ld</code> or whatever is appropriate.
46
47<p>Alternatively, you can do subsequent compilation using a value of the
48<code>PATH</code> environment variable such that the necessary GNU tools come
49before the standard system tools.
50
51</p><li>Specify the host, build and target machine configurations.  You do this
52when you run the <code>configure</code> script.
53
54<p>The <dfn>build</dfn> machine is the system which you are using, the
55<dfn>host</dfn> machine is the system where you want to run the resulting
56compiler (normally the build machine), and the <dfn>target</dfn> machine is
57the system for which you want the compiler to generate code.
58
59<p>If you are building a compiler to produce code for the machine it runs
60on (a native compiler), you normally do not need to specify any operands
61to <code>configure</code>; it will try to guess the type of machine you are on
62and use that as the build, host and target machines.  So you don't need
63to specify a configuration when building a native compiler unless
64<code>configure</code> cannot figure out what your configuration is or guesses
65wrong.
66
67<p>In those cases, specify the build machine's <dfn>configuration name</dfn>
68with the <code>--host</code> option; the host and target will default to be
69the same as the host machine.  (If you are building a cross-compiler,
70see <a href="#Cross-Compiler">Cross-Compiler</a>.)
71
72<p>Here is an example:
73
74<br><pre>./configure --host=sparc-sun-sunos4.1
75</pre>
76
77<p>A configuration name may be canonical or it may be more or less
78abbreviated.
79
80<p>A canonical configuration name has three parts, separated by dashes. 
81It looks like this: <code><var>cpu</var>-<var>company</var>-<var>system</var></code>. 
82(The three parts may themselves contain dashes; <code>configure</code>
83can figure out which dashes serve which purpose.)  For example,
84<code>m68k-sun-sunos4.1</code> specifies a Sun 3.
85
86<p>You can also replace parts of the configuration by nicknames or aliases. 
87For example, <code>sun3</code> stands for <code>m68k-sun</code>, so
88<code>sun3-sunos4.1</code> is another way to specify a Sun 3.
89
90<p>You can specify a version number after any of the system types, and some
91of the CPU types.  In most cases, the version is irrelevant, and will be
92ignored.  So you might as well specify the version if you know it.
93
94<p>See <a href="#Configurations">Configurations</a>, for a list of supported configuration names and
95notes on many of the configurations.  You should check the notes in that
96section before proceeding any further with the installation of GNU CC.
97
98</ol>
99
100<h2><a name="Configurations"></a>Configurations Supported by GNU CC</h2>
101
102<p>Here are the possible CPU types:
103
104<blockquote>
1051750a, a29k, alpha, arm, avr, c<var>n</var>, clipper, dsp16xx, elxsi, fr30, h8300,
106hppa1.0, hppa1.1, i370, i386, i486, i586, i686, i786, i860, i960, ip2k, m32r,
107m68000, m68k, m6811, m6812, m88k, mcore, mips, mipsel, mips64, mips64el,
108mn10200, mn10300, ns32k, pdp11, powerpc, powerpcle, romp, rs6000, sh, sparc,
109sparclite, sparc64, v850, vax, we32k. 
110</blockquote>
111
112<p>Here are the recognized company names.  As you can see, customary
113abbreviations are used rather than the longer official names.
114
115<blockquote>
116acorn, alliant, altos, apollo, apple, att, bull,
117cbm, convergent, convex, crds, dec, dg, dolphin,
118elxsi, encore, harris, hitachi, hp, ibm, intergraph, isi,
119mips, motorola, ncr, next, ns, omron, plexus,
120sequent, sgi, sony, sun, tti, unicom, wrs. 
121</blockquote>
122
123<p>The company name is meaningful only to disambiguate when the rest of
124the information supplied is insufficient.  You can omit it, writing
125just <code><var>cpu</var>-<var>system</var></code>, if it is not needed.  For example,
126<code>vax-ultrix4.2</code> is equivalent to <code>vax-dec-ultrix4.2</code>.
127
128<p>Here is a list of system types:
129
130<blockquote>
131386bsd, aix, acis, amigaos, aos, aout, aux, bosx, bsd, clix, coff, ctix, cxux,
132dgux, dynix, ebmon, ecoff, elf, esix, freebsd, hms, genix, gnu, linux,
133linux-gnu, hiux, hpux, iris, irix, isc, luna, lynxos, mach, minix, msdos, mvs,
134netbsd, newsos, nindy, ns, osf, osfrose, ptx, riscix, riscos, rtu, sco, sim,
135solaris, sunos, sym, sysv, udi, ultrix, unicos, uniplus, unos, vms, vsta,
136vxworks, winnt, xenix. 
137</blockquote>
138
139<p>You can omit the system type; then <code>configure</code> guesses the
140operating system from the CPU and company.
141
142<p>You can add a version number to the system type; this may or may not
143make a difference.  For example, you can write <code>bsd4.3</code> or
144<code>bsd4.4</code> to distinguish versions of BSD.  In practice, the version
145number is most needed for <code>sysv3</code> and <code>sysv4</code>, which are often
146treated differently.
147
148<p><code>linux-gnu</code> is the canonical name for the GNU/Linux target; however
149GNU CC will also accept <code>linux</code>.  The version of the kernel in use is
150not relevant on these systems.  A suffix such as <code>libc1</code> or <code>aout</code>
151distinguishes major versions of the C library; all of the suffixed versions
152are obsolete.
153
154<p>If you specify an impossible combination such as <code>i860-dg-vms</code>,
155then you may get an error message from <code>configure</code>, or it may
156ignore part of the information and do the best it can with the rest. 
157<code>configure</code> always prints the canonical name for the alternative
158that it used.  GNU CC does not support all possible alternatives.
159
160<p>Often a particular model of machine has a name.  Many machine names are
161recognized as aliases for CPU/company combinations.  Thus, the machine
162name <code>sun3</code>, mentioned above, is an alias for <code>m68k-sun</code>. 
163Sometimes we accept a company name as a machine name, when the name is
164popularly used for a particular machine.  Here is a table of the known
165machine names:
166
167<blockquote>
1683300, 3b1, 3b<var>n</var>, 7300, altos3068, altos,
169apollo68, att-7300, balance,
170convex-c<var>n</var>, crds, decstation-3100,
171decstation, delta, encore,
172fx2800, gmicro, hp7<var>nn</var>, hp8<var>nn</var>,
173hp9k2<var>nn</var>, hp9k3<var>nn</var>, hp9k7<var>nn</var>,
174hp9k8<var>nn</var>, iris4d, iris, isi68,
175m3230, magnum, merlin, miniframe,
176mmax, news-3600, news800, news, next,
177pbd, pc532, pmax, powerpc, powerpcle, ps2, risc-news,
178rtpc, sun2, sun386i, sun386, sun3,
179sun4, symmetry, tower-32, tower. 
180</blockquote>
181
182<p>Remember that a machine name specifies both the cpu type and the company
183name. 
184If you want to install your own homemade configuration files, you can
185use <code>local</code> as the company name to access them.  If you use
186configuration <code><var>cpu</var>-local</code>, the configuration name
187without the cpu prefix
188is used to form the configuration file names.
189
190<p>Thus, if you specify <code>m68k-local</code>, configuration uses
191files <code>m68k.md</code>, <code>local.h</code>, <code>m68k.c</code>,
192<code>xm-local.h</code>, <code>t-local</code>, and <code>x-local</code>, all in the
193directory <code>config/m68k</code>.
194
195<p>Here is a list of configurations that have special treatment or special
196things you must know:
197
198<dl>
199<dt><code>vax-dec-vms</code>
200<dd>See <a href="#VMS%20Install">VMS Install</a>, for details on how to install GNU CC on VMS. 
201</dl>
202
203<h2><a name="Cross-Compiler"></a>Building and Installing a Cross-Compiler</h2>
204
205<p>GNU CC can function as a cross-compiler for many machines, but not all.
206
207<ul>
208<li>Cross-compilers for the Mips as target using the Mips assembler
209currently do not work, because the auxiliary programs
210<code>mips-tdump.c</code> and <code>mips-tfile.c</code> can't be compiled on
211anything but a Mips.  It does work to cross compile for a Mips
212if you use the GNU assembler and linker.
213
214<li>Cross-compilers between machines with different floating point formats
215have not all been made to work.  GNU CC now has a floating point
216emulator with which these can work, but each target machine description
217needs to be updated to take advantage of it.
218
219<li>Cross-compilation between machines of different word sizes is
220somewhat problematic and sometimes does not work. 
221</ul>
222
223<p>Since GNU CC generates assembler code, you probably need a
224cross-assembler that GNU CC can run, in order to produce object files. 
225If you want to link on other than the target machine, you need a
226cross-linker as well.  You also need header files and libraries suitable
227for the target machine that you can install on the host machine.
228
229<h2>Steps of Cross-Compilation</h2>
230
231<p>To compile and run a program using a cross-compiler involves several
232steps:
233
234<ul>
235<li>Run the cross-compiler on the host machine to produce assembler files
236for the target machine.  This requires header files for the target
237machine.
238
239<li>Assemble the files produced by the cross-compiler.  You can do this
240either with an assembler on the target machine, or with a
241cross-assembler on the host machine.
242
243<li>Link those files to make an executable.  You can do this either with a
244linker on the target machine, or with a cross-linker on the host
245machine.  Whichever machine you use, you need libraries and certain
246startup files (typically <code>crt<small>...</small>.o</code>) for the target machine. 
247</ul>
248
249<p>It is most convenient to do all of these steps on the same host machine,
250since then you can do it all with a single invocation of GNU CC.  This
251requires a suitable cross-assembler and cross-linker.  For some targets,
252the GNU assembler and linker are available.
253
254<h2>Configuring a Cross-Compiler</h2>
255
256<p>To build GNU CC as a cross-compiler, you start out by running
257<code>configure</code>.  Use the <code>--target=<var>target</var></code> to specify the
258target type.  If <code>configure</code> was unable to correctly identify the
259system you are running on, also specify the <code>--build=<var>build</var></code>
260option.  For example, here is how to configure for a cross-compiler that
261produces code for an HP 68030 system running BSD on a system that
262<code>configure</code> can correctly identify:
263
264<br><pre>./configure --target=m68k-hp-bsd4.3
265</pre>
266
267<h2>Tools and Libraries for a Cross-Compiler</h2>
268
269<p>If you have a cross-assembler and cross-linker available, you should
270install them now.  Put them in the directory
271<code>/usr/local/<var>target</var>/bin</code>.  Here is a table of the tools
272you should put in this directory:
273
274<dl>
275<dt><code>as</code>
276<dd>This should be the cross-assembler.
277
278<br><dt><code>ld</code>
279<dd>This should be the cross-linker.
280
281<br><dt><code>ar</code>
282<dd>This should be the cross-archiver: a program which can manipulate
283archive files (linker libraries) in the target machine's format.
284
285<br><dt><code>ranlib</code>
286<dd>This should be a program to construct a symbol table in an archive file. 
287</dl>
288
289<p>The installation of GNU CC will find these programs in that directory,
290and copy or link them to the proper place to for the cross-compiler to
291find them when run later.
292
293<p>The easiest way to provide these files is to build the Binutils package
294and GAS.  Configure them with the same <code>--host</code> and <code>--target</code>
295options that you use for configuring GNU CC, then build and install
296them.  They install their executables automatically into the proper
297directory.  Alas, they do not support all the targets that GNU CC
298supports.
299
300<p>If you want to install libraries to use with the cross-compiler, such as
301a standard C library, put them in the directory
302<code>/usr/local/<var>target</var>/lib</code>; installation of GNU CC copies
303all the files in that subdirectory into the proper place for GNU CC to
304find them and link with them.  Here's an example of copying some
305libraries from a target machine:
306
307<br><pre>ftp <var>target-machine</var>
308lcd /usr/local/<var>target</var>/lib
309cd /lib
310get libc.a
311cd /usr/lib
312get libg.a
313get libm.a
314quit
315</pre>
316
317<p>The precise set of libraries you'll need, and their locations on
318the target machine, vary depending on its operating system.
319
320<p>Many targets require "start files" such as <code>crt0.o</code> and
321<code>crtn.o</code> which are linked into each executable; these too should be
322placed in <code>/usr/local/<var>target</var>/lib</code>.  There may be several
323alternatives for <code>crt0.o</code>, for use with profiling or other
324compilation options.  Check your target's definition of
325<code>STARTFILE_SPEC</code> to find out what start files it uses. 
326Here's an example of copying these files from a target machine:
327
328<br><pre>ftp <var>target-machine</var>
329lcd /usr/local/<var>target</var>/lib
330prompt
331cd /lib
332mget *crt*.o
333cd /usr/lib
334mget *crt*.o
335quit
336</pre>
337
338<h2>Cross-Compilers and Header Files</h2>
339
340<p>If you are cross-compiling a standalone program or a program for an
341embedded system, then you may not need any header files except the few
342that are part of GNU CC (and those of your program).  However, if you
343intend to link your program with a standard C library such as
344<code>libc.a</code>, then you probably need to compile with the header files
345that go with the library you use.
346
347<p>The GNU C compiler does not come with these files, because (1) they are
348system-specific, and (2) they belong in a C library, not in a compiler.
349
350<p>If the GNU C library supports your target machine, then you can get the
351header files from there (assuming you actually use the GNU library when
352you link your program).
353
354<p>If your target machine comes with a C compiler, it probably comes with
355suitable header files also.  If you make these files accessible from the host
356machine, the cross-compiler can use them also.
357
358<p>Otherwise, you're on your own in finding header files to use when
359cross-compiling.
360
361<p>When you have found suitable header files, you should put them in the
362directory <code>/usr/local/<var>target</var>/include</code>, before building the
363cross compiler.  Then installation will run fixincludes properly and
364install the corrected versions of the header files where the compiler
365will use them.
366
367<p>Provide the header files before you build the cross-compiler, because
368the build stage actually runs the cross-compiler to produce parts of
369<code>libgcc.a</code>.  (These are the parts that <em>can</em> be compiled with
370GNU CC.)  Some of them need suitable header files.
371
372<p>Here's an example showing how to copy the header files from a target
373machine.  On the target machine, do this:
374
375<br><pre>(cd /usr/include; tar cf - .) &gt; tarfile
376</pre>
377
378<p>Then, on the host machine, do this:
379
380<br><pre>ftp <var>target-machine</var>
381lcd /usr/local/<var>target</var>/include
382get tarfile
383quit
384tar xf tarfile
385</pre>
386
387<h2>Actually Building the Cross-Compiler</h2>
388
389<p>Now you can proceed just as for compiling a single-machine compiler
390through the step of building stage 1.
391
392<p>Do not try to build stage 2 for a cross-compiler.  It doesn't work to
393rebuild GNU CC as a cross-compiler using the cross-compiler, because
394that would produce a program that runs on the target machine, not on the
395host.  For example, if you compile a 386-to-68030 cross-compiler with
396itself, the result will not be right either for the 386 (because it was
397compiled into 68030 code) or for the 68030 (because it was configured
398for a 386 as the host).  If you want to compile GNU CC into 68030 code,
399whether you compile it on a 68030 or with a cross-compiler on a 386, you
400must specify a 68030 as the host when you configure it.
401
402<p>To install the cross-compiler, use <code>make install</code>, as usual.
403
404<h2><a name="VMS%20Install"></a>Installing GNU CC on VMS</h2>
405
406<p>The VMS version of GNU CC is distributed in a backup saveset containing
407both source code and precompiled binaries.
408
409<p>To install the <code>gcc</code> command so you can use the compiler easily, in
410the same manner as you use the VMS C compiler, you must install the VMS CLD
411file for GNU CC as follows:
412
413<ol type=1 start=1>
414</p><li>Define the VMS logical names <code>GNU_CC</code> and <code>GNU_CC_INCLUDE</code>
415to point to the directories where the GNU CC executables
416(<code>gcc-cpp.exe</code>, <code>gcc-cc1.exe</code>, etc.) and the C include files are
417kept respectively.  This should be done with the commands:
418
419<br><pre>$ assign /system /translation=concealed -
420  disk:[gcc.] gnu_cc
421$ assign /system /translation=concealed -
422  disk:[gcc.include.] gnu_cc_include
423</pre>
424
425<p>with the appropriate disk and directory names.  These commands can be
426placed in your system startup file so they will be executed whenever
427the machine is rebooted.  You may, if you choose, do this via the
428<code>GCC_INSTALL.COM</code> script in the <code>[GCC]</code> directory.
429
430</p><li>Install the <code>GCC</code> command with the command line:
431
432<br><pre>$ set command /table=sys$common:[syslib]dcltables -
433  /output=sys$common:[syslib]dcltables gnu_cc:[000000]gcc
434$ install replace sys$common:[syslib]dcltables
435</pre>
436
437<li>To install the help file, do the following:
438
439<br><pre>$ library/help sys$library:helplib.hlb gcc.hlp
440</pre>
441
442<p>Now you can invoke the compiler with a command like <code>gcc /verbose
443file.c</code>, which is equivalent to the command <code>gcc -v -c file.c</code> in
444Unix.
445</ol>
446
447<p>If you wish to use GNU C++ you must first install GNU CC, and then
448perform the following steps:
449
450<ol type=1 start=1>
451</p><li>Define the VMS logical name <code>GNU_GXX_INCLUDE</code> to point to the
452directory where the preprocessor will search for the C++ header files. 
453This can be done with the command:
454
455<br><pre>$ assign /system /translation=concealed -
456  disk:[gcc.gxx_include.] gnu_gxx_include
457</pre>
458
459<p>with the appropriate disk and directory name.  If you are going to be
460using a C++ runtime library, this is where its install procedure will install
461its header files.
462
463</p><li>Obtain the file <code>gcc-cc1plus.exe</code>, and place this in the same
464directory that <code>gcc-cc1.exe</code> is kept.
465
466<p>The GNU C++ compiler can be invoked with a command like <code>gcc /plus
467/verbose file.cc</code>, which is equivalent to the command <code>g++ -v -c
468file.cc</code> in Unix.
469</ol>
470
471<p>We try to put corresponding binaries and sources on the VMS distribution
472tape.  But sometimes the binaries will be from an older version than the
473sources, because we don't always have time to update them.  (Use the
474<code>/version</code> option to determine the version number of the binaries and
475compare it with the source file <code>version.c</code> to tell whether this is
476so.)  In this case, you should use the binaries you get to recompile the
477sources.  If you must recompile, here is how:
478
479<ol type=1 start=1>
480</p><li>Execute the command procedure <code>vmsconfig.com</code> to set up the files
481<code>tm.h</code>, <code>config.h</code>, <code>aux-output.c</code>, and <code>md.</code>, and
482to create files <code>tconfig.h</code> and <code>hconfig.h</code>.  This procedure
483also creates several linker option files used by <code>make-cc1.com</code> and
484a data file used by <code>make-l2.com</code>.
485
486<br><pre>$ @vmsconfig.com
487</pre>
488
489<li>Setup the logical names and command tables as defined above.  In
490addition, define the VMS logical name <code>GNU_BISON</code> to point at the
491to the directories where the Bison executable is kept.  This should be
492done with the command:
493
494<br><pre>$ assign /system /translation=concealed -
495  disk:[bison.] gnu_bison
496</pre>
497
498<p>You may, if you choose, use the <code>INSTALL_BISON.COM</code> script in the
499<code>[BISON]</code> directory.
500
501</p><li>Install the <code>BISON</code> command with the command line:
502
503<br><pre>$ set command /table=sys$common:[syslib]dcltables -
504  /output=sys$common:[syslib]dcltables -
505  gnu_bison:[000000]bison
506$ install replace sys$common:[syslib]dcltables
507</pre>
508
509<li>Type <code>@make-gcc</code> to recompile everything, or submit the file
510<code>make-gcc.com</code> to a batch queue.  If you wish to build the GNU C++
511compiler as well as the GNU CC compiler, you must first edit
512<code>make-gcc.com</code> and follow the instructions that appear in the
513comments.
514
515<li>In order to use GCC, you need a library of functions which GCC compiled code
516will call to perform certain tasks, and these functions are defined in the
517file <code>libgcc2.c</code>.  To compile this you should use the command procedure
518<code>make-l2.com</code>, which will generate the library <code>libgcc2.olb</code>. 
519<code>libgcc2.olb</code> should be built using the compiler built from
520the same distribution that <code>libgcc2.c</code> came from, and
521<code>make-gcc.com</code> will automatically do all of this for you.
522
523<p>To install the library, use the following commands:
524
525<br><pre>$ library gnu_cc:[000000]gcclib/delete=(new,eprintf)
526$ library gnu_cc:[000000]gcclib/delete=L_*
527$ library libgcc2/extract=*/output=libgcc2.obj
528$ library gnu_cc:[000000]gcclib libgcc2.obj
529</pre>
530
531<p>The first command simply removes old modules that will be replaced with
532modules from <code>libgcc2</code> under different module names.  The modules
533<code>new</code> and <code>eprintf</code> may not actually be present in your
534<code>gcclib.olb</code>--if the VMS librarian complains about those modules
535not being present, simply ignore the message and continue on with the
536next command.  The second command removes the modules that came from the
537previous version of the library <code>libgcc2.c</code>.
538
539<p>Whenever you update the compiler on your system, you should also update the
540library with the above procedure.
541
542</p><li>You may wish to build GCC in such a way that no files are written to the
543directory where the source files reside.  An example would be the when
544the source files are on a read-only disk.  In these cases, execute the
545following DCL commands (substituting your actual path names):
546
547<br><pre>$ assign dua0:[gcc.build_dir.]/translation=concealed, -
548         dua1:[gcc.source_dir.]/translation=concealed  gcc_build
549$ set default gcc_build:[000000]
550</pre>
551
552<p>where the directory <code>dua1:[gcc.source_dir]</code> contains the source
553code, and the directory <code>dua0:[gcc.build_dir]</code> is meant to contain
554all of the generated object files and executables.  Once you have done
555this, you can proceed building GCC as described above.  (Keep in mind
556that <code>gcc_build</code> is a rooted logical name, and thus the device
557names in each element of the search list must be an actual physical
558device name rather than another rooted logical name).
559
560</p><li><strong>If you are building GNU CC with a previous version of GNU CC,
561you also should check to see that you have the newest version of the
562assembler</strong>.  In particular, GNU CC version 2 treats global constant
563variables slightly differently from GNU CC version 1, and GAS version
5641.38.1 does not have the patches required to work with GCC version 2. 
565If you use GAS 1.38.1, then <code>extern const</code> variables will not have
566the read-only bit set, and the linker will generate warning messages
567about mismatched psect attributes for these variables.  These warning
568messages are merely a nuisance, and can safely be ignored.
569
570<li>If you want to build GNU CC with the VAX C compiler, you will need to
571make minor changes in <code>make-cccp.com</code> and <code>make-cc1.com</code>
572to choose alternate definitions of <code>CC</code>, <code>CFLAGS</code>, and
573<code>LIBS</code>.  See comments in those files.  However, you must
574also have a working version of the GNU assembler (GNU as, aka GAS) as
575it is used as the back end for GNU CC to produce binary object modules
576and is not included in the GNU CC sources.  GAS is also needed to
577compile <code>libgcc2</code> in order to build <code>gcclib</code> (see above);
578<code>make-l2.com</code> expects to be able to find it operational in
579<code>gnu_cc:[000000]gnu-as.exe</code>.
580
581<p>To use GNU CC on VMS, you need the VMS driver programs
582<code>gcc.exe</code>, <code>gcc.com</code>, and <code>gcc.cld</code>.  They are
583distributed with the VMS binaries (<code>gcc-vms</code>) rather than the
584GNU CC sources.  GAS is also included in <code>gcc-vms</code>, as is Bison.
585
586<p>Once you have successfully built GNU CC with VAX C, you should use the
587resulting compiler to rebuild itself.  Before doing this, be sure to
588restore the <code>CC</code>, <code>CFLAGS</code>, and <code>LIBS</code> definitions in
589<code>make-cccp.com</code> and <code>make-cc1.com</code>.  The second generation
590compiler will be able to take advantage of many optimizations that must
591be suppressed when building with other compilers.
592</ol>
593
594<p>Under previous versions of GNU CC, the generated code would occasionally
595give strange results when linked with the sharable <code>VAXCRTL</code> library. 
596Now this should work.
597
598<p>Even with this version, however, GNU CC itself should not be linked with
599the sharable <code>VAXCRTL</code>.  The version of <code>qsort</code> in
600<code>VAXCRTL</code> has a bug (known to be present in VMS versions V4.6
601through V5.5) which causes the compiler to fail.
602
603<p>The executables are generated by <code>make-cc1.com</code> and
604<code>make-cccp.com</code> use the object library version of <code>VAXCRTL</code> in
605order to make use of the <code>qsort</code> routine in <code>gcclib.olb</code>.  If
606you wish to link the compiler executables with the shareable image
607version of <code>VAXCRTL</code>, you should edit the file <code>tm.h</code> (created
608by <code>vmsconfig.com</code>) to define the macro <code>QSORT_WORKAROUND</code>.
609
610<p><code>QSORT_WORKAROUND</code> is always defined when GNU CC is compiled with
611VAX C, to avoid a problem in case <code>gcclib.olb</code> is not yet
612available. 
613<hr />
614<p>
615<a href="./index.html">Return to the GCC Installation page</a>
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