1 @c Copyright (C) 2002-2020 Free Software Foundation, Inc.
2 @c This is part of the GCC manual.
3 @c For copying conditions, see the file gcc.texi.
6 @chapter Source Tree Structure and Build System
8 This chapter describes the structure of the GCC source tree, and how
9 GCC is built. The user documentation for building and installing GCC
10 is in a separate manual (@uref{http://gcc.gnu.org/install/}), with
11 which it is presumed that you are familiar.
14 * Configure Terms:: Configuration terminology and history.
15 * Top Level:: The top level source directory.
16 * gcc Directory:: The @file{gcc} subdirectory.
19 @include configterms.texi
22 @section Top Level Source Directory
24 The top level source directory in a GCC distribution contains several
25 files and directories that are shared with other software
26 distributions such as that of GNU Binutils. It also contains several
27 subdirectories that contain parts of GCC and its runtime libraries:
31 The Boehm conservative garbage collector, optionally used as part of
32 the ObjC runtime library when configured with @option{--enable-objc-gc}.
35 Autoconf macros and Makefile fragments used throughout the tree.
38 Contributed scripts that may be found useful in conjunction with GCC@.
39 One of these, @file{contrib/texi2pod.pl}, is used to generate man
40 pages from Texinfo manuals as part of the GCC build process.
43 The support for fixing system headers to work with GCC@. See
44 @file{fixincludes/README} for more information. The headers fixed by
45 this mechanism are installed in @file{@var{libsubdir}/include-fixed}.
46 Along with those headers, @file{README-fixinc} is also installed, as
47 @file{@var{libsubdir}/include-fixed/README}.
50 The main sources of GCC itself (except for runtime libraries),
51 including optimizers, support for different target architectures,
52 language front ends, and testsuites. @xref{gcc Directory, , The
53 @file{gcc} Subdirectory}, for details.
56 Support tools for GNAT.
59 Headers for the @code{libiberty} library.
62 GNU @code{libintl}, from GNU @code{gettext}, for systems which do not
63 include it in @code{libc}.
66 The Ada runtime library.
69 The runtime support library for atomic operations (e.g.@: for @code{__sync}
73 The C preprocessor library.
76 The Decimal Float support library.
79 The @code{libffi} library, used as part of the Go runtime library.
82 The GCC runtime library.
85 The Fortran runtime library.
88 The Go runtime library. The bulk of this library is mirrored from the
89 @uref{https://github.com/@/golang/go, master Go repository}.
92 The GNU Offloading and Multi Processing Runtime Library.
95 The @code{libiberty} library, used for portability and for some
96 generally useful data structures and algorithms. @xref{Top, ,
97 Introduction, libiberty, @sc{gnu} libiberty}, for more information
101 The runtime support library for transactional memory.
104 The Objective-C and Objective-C++ runtime library.
107 The runtime support library for quad-precision math operations.
110 The D standard and runtime library. The bulk of this library is mirrored
111 from the @uref{https://github.com/@/dlang, master D repositories}.
114 The Stack protector runtime library.
117 The C++ runtime library.
120 Plugin used by the linker if link-time optimizations are enabled.
122 @item maintainer-scripts
123 Scripts used by the @code{gccadmin} account on @code{gcc.gnu.org}.
126 The @code{zlib} compression library, used for compressing and
127 uncompressing GCC's intermediate language in LTO object files.
130 The build system in the top level directory, including how recursion
131 into subdirectories works and how building runtime libraries for
132 multilibs is handled, is documented in a separate manual, included
133 with GNU Binutils. @xref{Top, , GNU configure and build system,
134 configure, The GNU configure and build system}, for details.
137 @section The @file{gcc} Subdirectory
139 The @file{gcc} directory contains many files that are part of the C
140 sources of GCC, other files used as part of the configuration and
141 build process, and subdirectories including documentation and a
142 testsuite. The files that are sources of GCC are documented in a
143 separate chapter. @xref{Passes, , Passes and Files of the Compiler}.
146 * Subdirectories:: Subdirectories of @file{gcc}.
147 * Configuration:: The configuration process, and the files it uses.
148 * Build:: The build system in the @file{gcc} directory.
149 * Makefile:: Targets in @file{gcc/Makefile}.
150 * Library Files:: Library source files and headers under @file{gcc/}.
151 * Headers:: Headers installed by GCC.
152 * Documentation:: Building documentation in GCC.
153 * Front End:: Anatomy of a language front end.
154 * Back End:: Anatomy of a target back end.
158 @subsection Subdirectories of @file{gcc}
160 The @file{gcc} directory contains the following subdirectories:
164 Subdirectories for various languages. Directories containing a file
165 @file{config-lang.in} are language subdirectories. The contents of
166 the subdirectories @file{c} (for C), @file{cp} (for C++),
167 @file{objc} (for Objective-C), @file{objcp} (for Objective-C++),
168 and @file{lto} (for LTO) are documented in this
169 manual (@pxref{Passes, , Passes and Files of the Compiler});
170 those for other languages are not. @xref{Front End, ,
171 Anatomy of a Language Front End}, for details of the files in these
175 Source files shared between the compiler drivers (such as
176 @command{gcc}) and the compilers proper (such as @file{cc1}). If an
177 architecture defines target hooks shared between those places, it also
178 has a subdirectory in @file{common/config}. @xref{Target Structure}.
181 Configuration files for supported architectures and operating
182 systems. @xref{Back End, , Anatomy of a Target Back End}, for
183 details of the files in this directory.
186 Texinfo documentation for GCC, together with automatically generated
187 man pages and support for converting the installation manual to
188 HTML@. @xref{Documentation}.
191 System headers installed by GCC, mainly those required by the C
192 standard of freestanding implementations. @xref{Headers, , Headers
193 Installed by GCC}, for details of when these and other headers are
197 Message catalogs with translations of messages produced by GCC into
198 various languages, @file{@var{language}.po}. This directory also
199 contains @file{gcc.pot}, the template for these message catalogues,
200 @file{exgettext}, a wrapper around @command{gettext} to extract the
201 messages from the GCC sources and create @file{gcc.pot}, which is run
202 by @samp{make gcc.pot}, and @file{EXCLUDES}, a list of files from
203 which messages should not be extracted.
206 The GCC testsuites (except for those for runtime libraries).
211 @subsection Configuration in the @file{gcc} Directory
213 The @file{gcc} directory is configured with an Autoconf-generated
214 script @file{configure}. The @file{configure} script is generated
215 from @file{configure.ac} and @file{aclocal.m4}. From the files
216 @file{configure.ac} and @file{acconfig.h}, Autoheader generates the
217 file @file{config.in}. The file @file{cstamp-h.in} is used as a
221 * Config Fragments:: Scripts used by @file{configure}.
222 * System Config:: The @file{config.build}, @file{config.host}, and
223 @file{config.gcc} files.
224 * Configuration Files:: Files created by running @file{configure}.
227 @node Config Fragments
228 @subsubsection Scripts Used by @file{configure}
230 @file{configure} uses some other scripts to help in its work:
233 @item The standard GNU @file{config.sub} and @file{config.guess}
234 files, kept in the top level directory, are used.
236 @item The file @file{config.gcc} is used to handle configuration
237 specific to the particular target machine. The file
238 @file{config.build} is used to handle configuration specific to the
239 particular build machine. The file @file{config.host} is used to handle
240 configuration specific to the particular host machine. (In general,
241 these should only be used for features that cannot reasonably be tested in
242 Autoconf feature tests.)
243 @xref{System Config, , The @file{config.build}; @file{config.host};
244 and @file{config.gcc} Files}, for details of the contents of these files.
246 @item Each language subdirectory has a file
247 @file{@var{language}/config-lang.in} that is used for
248 front-end-specific configuration. @xref{Front End Config, , The Front
249 End @file{config-lang.in} File}, for details of this file.
251 @item A helper script @file{configure.frag} is used as part of
252 creating the output of @file{configure}.
256 @subsubsection The @file{config.build}; @file{config.host}; and @file{config.gcc} Files
258 The @file{config.build} file contains specific rules for particular systems
259 which GCC is built on. This should be used as rarely as possible, as the
260 behavior of the build system can always be detected by autoconf.
262 The @file{config.host} file contains specific rules for particular systems
263 which GCC will run on. This is rarely needed.
265 The @file{config.gcc} file contains specific rules for particular systems
266 which GCC will generate code for. This is usually needed.
268 Each file has a list of the shell variables it sets, with descriptions, at the
271 FIXME: document the contents of these files, and what variables should
272 be set to control build, host and target configuration.
274 @include configfiles.texi
277 @subsection Build System in the @file{gcc} Directory
279 FIXME: describe the build system, including what is built in what
280 stages. Also list the various source files that are used in the build
281 process but aren't source files of GCC itself and so aren't documented
282 below (@pxref{Passes}).
284 @include makefile.texi
287 @subsection Library Source Files and Headers under the @file{gcc} Directory
289 FIXME: list here, with explanation, all the C source files and headers
290 under the @file{gcc} directory that aren't built into the GCC
291 executable but rather are part of runtime libraries and object files,
292 such as @file{crtstuff.c} and @file{unwind-dw2.c}. @xref{Headers, ,
293 Headers Installed by GCC}, for more information about the
294 @file{ginclude} directory.
297 @subsection Headers Installed by GCC
299 In general, GCC expects the system C library to provide most of the
300 headers to be used with it. However, GCC will fix those headers if
301 necessary to make them work with GCC, and will install some headers
302 required of freestanding implementations. These headers are installed
303 in @file{@var{libsubdir}/include}. Headers for non-C runtime
304 libraries are also installed by GCC; these are not documented here.
305 (FIXME: document them somewhere.)
307 Several of the headers GCC installs are in the @file{ginclude}
308 directory. These headers, @file{iso646.h},
309 @file{stdarg.h}, @file{stdbool.h}, and @file{stddef.h},
310 are installed in @file{@var{libsubdir}/include},
311 unless the target Makefile fragment (@pxref{Target Fragment})
312 overrides this by setting @code{USER_H}.
314 In addition to these headers and those generated by fixing system
315 headers to work with GCC, some other headers may also be installed in
316 @file{@var{libsubdir}/include}. @file{config.gcc} may set
317 @code{extra_headers}; this specifies additional headers under
318 @file{config} to be installed on some systems.
320 GCC installs its own version of @code{<float.h>}, from @file{ginclude/float.h}.
321 This is done to cope with command-line options that change the
322 representation of floating point numbers.
324 GCC also installs its own version of @code{<limits.h>}; this is generated
325 from @file{glimits.h}, together with @file{limitx.h} and
326 @file{limity.h} if the system also has its own version of
327 @code{<limits.h>}. (GCC provides its own header because it is
328 required of ISO C freestanding implementations, but needs to include
329 the system header from its own header as well because other standards
330 such as POSIX specify additional values to be defined in
331 @code{<limits.h>}.) The system's @code{<limits.h>} header is used via
332 @file{@var{libsubdir}/include/syslimits.h}, which is copied from
333 @file{gsyslimits.h} if it does not need fixing to work with GCC; if it
334 needs fixing, @file{syslimits.h} is the fixed copy.
336 GCC can also install @code{<tgmath.h>}. It will do this when
337 @file{config.gcc} sets @code{use_gcc_tgmath} to @code{yes}.
340 @subsection Building Documentation
342 The main GCC documentation is in the form of manuals in Texinfo
343 format. These are installed in Info format; DVI versions may be
344 generated by @samp{make dvi}, PDF versions by @samp{make pdf}, and
345 HTML versions by @samp{make html}. In addition, some man pages are
346 generated from the Texinfo manuals, there are some other text files
347 with miscellaneous documentation, and runtime libraries have their own
348 documentation outside the @file{gcc} directory. FIXME: document the
349 documentation for runtime libraries somewhere.
352 * Texinfo Manuals:: GCC manuals in Texinfo format.
353 * Man Page Generation:: Generating man pages from Texinfo manuals.
354 * Miscellaneous Docs:: Miscellaneous text files with documentation.
357 @node Texinfo Manuals
358 @subsubsection Texinfo Manuals
360 The manuals for GCC as a whole, and the C and C++ front ends, are in
361 files @file{doc/*.texi}. Other front ends have their own manuals in
362 files @file{@var{language}/*.texi}. Common files
363 @file{doc/include/*.texi} are provided which may be included in
364 multiple manuals; the following files are in @file{doc/include}:
368 The GNU Free Documentation License.
370 The section ``Funding Free Software''.
371 @item gcc-common.texi
372 Common definitions for manuals.
374 The GNU General Public License.
376 A copy of @file{texinfo.tex} known to work with the GCC manuals.
379 DVI-formatted manuals are generated by @samp{make dvi}, which uses
380 @command{texi2dvi} (via the Makefile macro @code{$(TEXI2DVI)}).
381 PDF-formatted manuals are generated by @samp{make pdf}, which uses
382 @command{texi2pdf} (via the Makefile macro @code{$(TEXI2PDF)}). HTML
383 formatted manuals are generated by @samp{make html}. Info
384 manuals are generated by @samp{make info} (which is run as part of
385 a bootstrap); this generates the manuals in the source directory,
386 using @command{makeinfo} via the Makefile macro @code{$(MAKEINFO)},
387 and they are included in release distributions.
389 Manuals are also provided on the GCC web site, in both HTML and
390 PostScript forms. This is done via the script
391 @file{maintainer-scripts/update_web_docs_git}. Each manual to be
392 provided online must be listed in the definition of @code{MANUALS} in
393 that file; a file @file{@var{name}.texi} must only appear once in the
394 source tree, and the output manual must have the same name as the
395 source file. (However, other Texinfo files, included in manuals but
396 not themselves the root files of manuals, may have names that appear
397 more than once in the source tree.) The manual file
398 @file{@var{name}.texi} should only include other files in its own
399 directory or in @file{doc/include}. HTML manuals will be generated by
400 @samp{makeinfo --html}, PostScript manuals by @command{texi2dvi}
401 and @command{dvips}, and PDF manuals by @command{texi2pdf}.
402 All Texinfo files that are parts of manuals must
403 be version-controlled, even if they are generated files, for the
404 generation of online manuals to work.
406 The installation manual, @file{doc/install.texi}, is also provided on
407 the GCC web site. The HTML version is generated by the script
408 @file{doc/install.texi2html}.
410 @node Man Page Generation
411 @subsubsection Man Page Generation
413 Because of user demand, in addition to full Texinfo manuals, man pages
414 are provided which contain extracts from those manuals. These man
415 pages are generated from the Texinfo manuals using
416 @file{contrib/texi2pod.pl} and @command{pod2man}. (The man page for
417 @command{g++}, @file{cp/g++.1}, just contains a @samp{.so} reference
418 to @file{gcc.1}, but all the other man pages are generated from
421 Because many systems may not have the necessary tools installed to
422 generate the man pages, they are only generated if the
423 @file{configure} script detects that recent enough tools are
424 installed, and the Makefiles allow generating man pages to fail
425 without aborting the build. Man pages are also included in release
426 distributions. They are generated in the source directory.
428 Magic comments in Texinfo files starting @samp{@@c man} control what
429 parts of a Texinfo file go into a man page. Only a subset of Texinfo
430 is supported by @file{texi2pod.pl}, and it may be necessary to add
431 support for more Texinfo features to this script when generating new
432 man pages. To improve the man page output, some special Texinfo
433 macros are provided in @file{doc/include/gcc-common.texi} which
434 @file{texi2pod.pl} understands:
438 Use in the form @samp{@@table @@gcctabopt} for tables of options,
439 where for printed output the effect of @samp{@@code} is better than
440 that of @samp{@@option} but for man page output a different effect is
443 Use for summary lists of options in manuals.
445 Use at the end of each line inside @samp{@@gccoptlist}. This is
446 necessary to avoid problems with differences in how the
447 @samp{@@gccoptlist} macro is handled by different Texinfo formatters.
450 FIXME: describe the @file{texi2pod.pl} input language and magic
451 comments in more detail.
453 @node Miscellaneous Docs
454 @subsubsection Miscellaneous Documentation
456 In addition to the formal documentation that is installed by GCC,
457 there are several other text files in the @file{gcc} subdirectory
458 with miscellaneous documentation:
462 Notes on GCC's Native Language Support. FIXME: this should be part of
463 this manual rather than a separate file.
465 Notes on the Free Translation Project.
468 The GNU General Public License, Versions 2 and 3.
471 The GNU Lesser General Public License, Versions 2.1 and 3.
474 Change log files for various parts of GCC@.
476 Details of a few changes to the GCC front-end interface. FIXME: the
477 information in this file should be part of general documentation of
478 the front-end interface in this manual.
480 Information about new features in old versions of GCC@. (For recent
481 versions, the information is on the GCC web site.)
482 @item README.Portability
483 Information about portability issues when writing code in GCC@. FIXME:
484 why isn't this part of this manual or of the GCC Coding Conventions?
487 FIXME: document such files in subdirectories, at least @file{config},
488 @file{c}, @file{cp}, @file{objc}, @file{testsuite}.
491 @subsection Anatomy of a Language Front End
493 A front end for a language in GCC has the following parts:
497 A directory @file{@var{language}} under @file{gcc} containing source
498 files for that front end. @xref{Front End Directory, , The Front End
499 @file{@var{language}} Directory}, for details.
501 A mention of the language in the list of supported languages in
502 @file{gcc/doc/install.texi}.
504 A mention of the name under which the language's runtime library is
505 recognized by @option{--enable-shared=@var{package}} in the
506 documentation of that option in @file{gcc/doc/install.texi}.
508 A mention of any special prerequisites for building the front end in
509 the documentation of prerequisites in @file{gcc/doc/install.texi}.
511 Details of contributors to that front end in
512 @file{gcc/doc/contrib.texi}. If the details are in that front end's
513 own manual then there should be a link to that manual's list in
516 Information about support for that language in
517 @file{gcc/doc/frontends.texi}.
519 Information about standards for that language, and the front end's
520 support for them, in @file{gcc/doc/standards.texi}. This may be a
521 link to such information in the front end's own manual.
523 Details of source file suffixes for that language and @option{-x
524 @var{lang}} options supported, in @file{gcc/doc/invoke.texi}.
526 Entries in @code{default_compilers} in @file{gcc.c} for source file
527 suffixes for that language.
529 Preferably testsuites, which may be under @file{gcc/testsuite} or
530 runtime library directories. FIXME: document somewhere how to write
533 Probably a runtime library for the language, outside the @file{gcc}
534 directory. FIXME: document this further.
536 Details of the directories of any runtime libraries in
537 @file{gcc/doc/sourcebuild.texi}.
539 Check targets in @file{Makefile.def} for the top-level @file{Makefile}
540 to check just the compiler or the compiler and runtime library for the
544 If the front end is added to the official GCC source repository, the
545 following are also necessary:
549 At least one Bugzilla component for bugs in that front end and runtime
550 libraries. This category needs to be added to the Bugzilla database.
552 Normally, one or more maintainers of that front end listed in
555 Mentions on the GCC web site in @file{index.html} and
556 @file{frontends.html}, with any relevant links on
557 @file{readings.html}. (Front ends that are not an official part of
558 GCC may also be listed on @file{frontends.html}, with relevant links.)
560 A news item on @file{index.html}, and possibly an announcement on the
561 @email{gcc-announce@@gcc.gnu.org} mailing list.
563 The front end's manuals should be mentioned in
564 @file{maintainer-scripts/update_web_docs_git} (@pxref{Texinfo Manuals})
565 and the online manuals should be linked to from
566 @file{onlinedocs/index.html}.
568 Any old releases or CVS repositories of the front end, before its
569 inclusion in GCC, should be made available on the GCC web site at
570 @uref{https://gcc.gnu.org/pub/gcc/old-releases/}.
572 The release and snapshot script @file{maintainer-scripts/gcc_release}
573 should be updated to generate appropriate tarballs for this front end.
575 If this front end includes its own version files that include the
576 current date, @file{maintainer-scripts/update_version} should be
581 * Front End Directory:: The front end @file{@var{language}} directory.
582 * Front End Config:: The front end @file{config-lang.in} file.
583 * Front End Makefile:: The front end @file{Make-lang.in} file.
586 @node Front End Directory
587 @subsubsection The Front End @file{@var{language}} Directory
589 A front end @file{@var{language}} directory contains the source files
590 of that front end (but not of any runtime libraries, which should be
591 outside the @file{gcc} directory). This includes documentation, and
592 possibly some subsidiary programs built alongside the front end.
593 Certain files are special and other parts of the compiler depend on
598 This file is required in all language subdirectories. @xref{Front End
599 Config, , The Front End @file{config-lang.in} File}, for details of
602 This file is required in all language subdirectories. @xref{Front End
603 Makefile, , The Front End @file{Make-lang.in} File}, for details of its
606 This file registers the set of switches that the front end accepts on
607 the command line, and their @option{--help} text. @xref{Options}.
609 This file provides entries for @code{default_compilers} in
610 @file{gcc.c} which override the default of giving an error that a
611 compiler for that language is not installed.
612 @item @var{language}-tree.def
613 This file, which need not exist, defines any language-specific tree
617 @node Front End Config
618 @subsubsection The Front End @file{config-lang.in} File
620 Each language subdirectory contains a @file{config-lang.in} file.
621 This file is a shell script that may define some variables describing
626 This definition must be present, and gives the name of the language
627 for some purposes such as arguments to @option{--enable-languages}.
629 If defined, this variable lists (space-separated) language front ends
630 other than C that this front end requires to be enabled (with the
631 names given being their @code{language} settings). For example, the
632 Obj-C++ front end depends on the C++ and ObjC front ends, so sets
633 @samp{lang_requires="objc c++"}.
634 @item subdir_requires
635 If defined, this variable lists (space-separated) front end directories
636 other than C that this front end requires to be present. For example,
637 the Objective-C++ front end uses source files from the C++ and
638 Objective-C front ends, so sets @samp{subdir_requires="cp objc"}.
640 If defined, this variable lists (space-separated) targets in the top
641 level @file{Makefile} to build the runtime libraries for this
642 language, such as @code{target-libobjc}.
644 If defined, this variable lists (space-separated) top level
645 directories (parallel to @file{gcc}), apart from the runtime libraries,
646 that should not be configured if this front end is not built.
647 @item build_by_default
648 If defined to @samp{no}, this language front end is not built unless
649 enabled in a @option{--enable-languages} argument. Otherwise, front
650 ends are built by default, subject to any special logic in
651 @file{configure.ac} (as is present to disable the Ada front end if the
652 Ada compiler is not already installed).
654 If defined to @samp{yes}, this front end is built in stage1 of the
655 bootstrap. This is only relevant to front ends written in their own
658 If defined, a space-separated list of compiler executables that will
659 be run by the driver. The names here will each end
660 with @samp{\$(exeext)}.
662 If defined, a space-separated list of files that should be generated
663 by @file{configure} substituting values in them. This mechanism can
664 be used to create a file @file{@var{language}/Makefile} from
665 @file{@var{language}/Makefile.in}, but this is deprecated, building
666 everything from the single @file{gcc/Makefile} is preferred.
668 If defined, a space-separated list of files that should be scanned by
669 @file{gengtype.c} to generate the garbage collection tables and routines for
670 this language. This excludes the files that are common to all front
671 ends. @xref{Type Information}.
675 @node Front End Makefile
676 @subsubsection The Front End @file{Make-lang.in} File
678 Each language subdirectory contains a @file{Make-lang.in} file. It contains
679 targets @code{@var{lang}.@var{hook}} (where @code{@var{lang}} is the
680 setting of @code{language} in @file{config-lang.in}) for the following
681 values of @code{@var{hook}}, and any other Makefile rules required to
682 build those targets (which may if necessary use other Makefiles
683 specified in @code{outputs} in @file{config-lang.in}, although this is
684 deprecated). It also adds any testsuite targets that can use the
685 standard rule in @file{gcc/Makefile.in} to the variable
692 FIXME: exactly what goes in each of these targets?
694 Build an @command{etags} @file{TAGS} file in the language subdirectory
697 Build info documentation for the front end, in the build directory.
698 This target is only called by @samp{make bootstrap} if a suitable
699 version of @command{makeinfo} is available, so does not need to check
700 for this, and should fail if an error occurs.
702 Build DVI documentation for the front end, in the build directory.
703 This should be done using @code{$(TEXI2DVI)}, with appropriate
704 @option{-I} arguments pointing to directories of included files.
706 Build PDF documentation for the front end, in the build directory.
707 This should be done using @code{$(TEXI2PDF)}, with appropriate
708 @option{-I} arguments pointing to directories of included files.
710 Build HTML documentation for the front end, in the build directory.
712 Build generated man pages for the front end from Texinfo manuals
713 (@pxref{Man Page Generation}), in the build directory. This target
714 is only called if the necessary tools are available, but should ignore
715 errors so as not to stop the build if errors occur; man pages are
716 optional and the tools involved may be installed in a broken way.
718 Install everything that is part of the front end, apart from the
719 compiler executables listed in @code{compilers} in
720 @file{config-lang.in}.
722 Install info documentation for the front end, if it is present in the
723 source directory. This target should have dependencies on info files
724 that should be installed.
726 Install man pages for the front end. This target should ignore
729 Install headers needed for plugins.
731 Copies its dependencies into the source directory. This generally should
732 be used for generated files such as Bison output files which are not
733 version-controlled, but should be included in any release tarballs. This
734 target will be executed during a bootstrap if
735 @samp{--enable-generated-files-in-srcdir} was specified as a
736 @file{configure} option.
739 Copies its dependencies into the source directory. These targets will be
740 executed during a bootstrap if @samp{--enable-generated-files-in-srcdir}
741 was specified as a @file{configure} option.
743 Uninstall files installed by installing the compiler. This is
744 currently documented not to be supported, so the hook need not do
749 @itemx maintainer-clean
750 The language parts of the standard GNU
751 @samp{*clean} targets. @xref{Standard Targets, , Standard Targets for
752 Users, standards, GNU Coding Standards}, for details of the standard
753 targets. For GCC, @code{maintainer-clean} should delete
754 all generated files in the source directory that are not version-controlled,
755 but should not delete anything that is.
758 @file{Make-lang.in} must also define a variable @code{@var{lang}_OBJS}
759 to a list of host object files that are used by that language.
762 @subsection Anatomy of a Target Back End
764 A back end for a target architecture in GCC has the following parts:
768 A directory @file{@var{machine}} under @file{gcc/config}, containing a
769 machine description @file{@var{machine}.md} file (@pxref{Machine Desc,
770 , Machine Descriptions}), header files @file{@var{machine}.h} and
771 @file{@var{machine}-protos.h} and a source file @file{@var{machine}.c}
772 (@pxref{Target Macros, , Target Description Macros and Functions}),
773 possibly a target Makefile fragment @file{t-@var{machine}}
774 (@pxref{Target Fragment, , The Target Makefile Fragment}), and maybe
775 some other files. The names of these files may be changed from the
776 defaults given by explicit specifications in @file{config.gcc}.
778 If necessary, a file @file{@var{machine}-modes.def} in the
779 @file{@var{machine}} directory, containing additional machine modes to
780 represent condition codes. @xref{Condition Code}, for further details.
782 An optional @file{@var{machine}.opt} file in the @file{@var{machine}}
783 directory, containing a list of target-specific options. You can also
784 add other option files using the @code{extra_options} variable in
785 @file{config.gcc}. @xref{Options}.
787 Entries in @file{config.gcc} (@pxref{System Config, , The
788 @file{config.gcc} File}) for the systems with this target
791 Documentation in @file{gcc/doc/invoke.texi} for any command-line
792 options supported by this target (@pxref{Run-time Target, , Run-time
793 Target Specification}). This means both entries in the summary table
794 of options and details of the individual options.
796 Documentation in @file{gcc/doc/extend.texi} for any target-specific
797 attributes supported (@pxref{Target Attributes, , Defining
798 target-specific uses of @code{__attribute__}}), including where the
799 same attribute is already supported on some targets, which are
800 enumerated in the manual.
802 Documentation in @file{gcc/doc/extend.texi} for any target-specific
805 Documentation in @file{gcc/doc/extend.texi} of any target-specific
806 built-in functions supported.
808 Documentation in @file{gcc/doc/extend.texi} of any target-specific
809 format checking styles supported.
811 Documentation in @file{gcc/doc/md.texi} of any target-specific
812 constraint letters (@pxref{Machine Constraints, , Constraints for
813 Particular Machines}).
815 A note in @file{gcc/doc/contrib.texi} under the person or people who
816 contributed the target support.
818 Entries in @file{gcc/doc/install.texi} for all target triplets
819 supported with this target architecture, giving details of any special
820 notes about installation for this target, or saying that there are no
821 special notes if there are none.
823 Possibly other support outside the @file{gcc} directory for runtime
824 libraries. FIXME: reference docs for this. The @code{libstdc++} porting
825 manual needs to be installed as info for this to work, or to be a
826 chapter of this manual.
829 The @file{@var{machine}.h} header is included very early in GCC's
830 standard sequence of header files, while @file{@var{machine}-protos.h}
831 is included late in the sequence. Thus @file{@var{machine}-protos.h}
832 can include declarations referencing types that are not defined when
833 @file{@var{machine}.h} is included, specifically including those from
834 @file{rtl.h} and @file{tree.h}. Since both RTL and tree types may not
835 be available in every context where @file{@var{machine}-protos.h} is
836 included, in this file you should guard declarations using these types
837 inside appropriate @code{#ifdef RTX_CODE} or @code{#ifdef TREE_CODE}
838 conditional code segments.
840 If the backend uses shared data structures that require @code{GTY} markers
841 for garbage collection (@pxref{Type Information}), you must declare those
842 in @file{@var{machine}.h} rather than @file{@var{machine}-protos.h}.
843 Any definitions required for building libgcc must also go in
844 @file{@var{machine}.h}.
846 GCC uses the macro @code{IN_TARGET_CODE} to distinguish between
847 machine-specific @file{.c} and @file{.cc} files and
848 machine-independent @file{.c} and @file{.cc} files. Machine-specific
849 files should use the directive:
852 #define IN_TARGET_CODE 1
855 before including @code{config.h}.
857 If the back end is added to the official GCC source repository, the
858 following are also necessary:
862 An entry for the target architecture in @file{readings.html} on the
863 GCC web site, with any relevant links.
865 Details of the properties of the back end and target architecture in
866 @file{backends.html} on the GCC web site.
868 A news item about the contribution of support for that target
869 architecture, in @file{index.html} on the GCC web site.
871 Normally, one or more maintainers of that target listed in
872 @file{MAINTAINERS}. Some existing architectures may be unmaintained,
873 but it would be unusual to add support for a target that does not have
874 a maintainer when support is added.
876 Target triplets covering all @file{config.gcc} stanzas for the target,
877 in the list in @file{contrib/config-list.mk}.
883 GCC contains several testsuites to help maintain compiler quality.
884 Most of the runtime libraries and language front ends in GCC have
885 testsuites. Currently only the C language testsuites are documented
886 here; FIXME: document the others.
889 * Test Idioms:: Idioms used in testsuite code.
890 * Test Directives:: Directives used within DejaGnu tests.
891 * Ada Tests:: The Ada language testsuites.
892 * C Tests:: The C language testsuites.
893 * LTO Testing:: Support for testing link-time optimizations.
894 * gcov Testing:: Support for testing gcov.
895 * profopt Testing:: Support for testing profile-directed optimizations.
896 * compat Testing:: Support for testing binary compatibility.
897 * Torture Tests:: Support for torture testing using multiple options.
898 * GIMPLE Tests:: Support for testing GIMPLE passes.
899 * RTL Tests:: Support for testing RTL passes.
903 @section Idioms Used in Testsuite Code
905 In general, C testcases have a trailing @file{-@var{n}.c}, starting
906 with @file{-1.c}, in case other testcases with similar names are added
907 later. If the test is a test of some well-defined feature, it should
908 have a name referring to that feature such as
909 @file{@var{feature}-1.c}. If it does not test a well-defined feature
910 but just happens to exercise a bug somewhere in the compiler, and a
911 bug report has been filed for this bug in the GCC bug database,
912 @file{pr@var{bug-number}-1.c} is the appropriate form of name.
913 Otherwise (for miscellaneous bugs not filed in the GCC bug database),
914 and previously more generally, test cases are named after the date on
915 which they were added. This allows people to tell at a glance whether
916 a test failure is because of a recently found bug that has not yet
917 been fixed, or whether it may be a regression, but does not give any
918 other information about the bug or where discussion of it may be
919 found. Some other language testsuites follow similar conventions.
921 In the @file{gcc.dg} testsuite, it is often necessary to test that an
922 error is indeed a hard error and not just a warning---for example,
923 where it is a constraint violation in the C standard, which must
924 become an error with @option{-pedantic-errors}. The following idiom,
925 where the first line shown is line @var{line} of the file and the line
926 that generates the error, is used for this:
929 /* @{ dg-bogus "warning" "warning in place of error" @} */
930 /* @{ dg-error "@var{regexp}" "@var{message}" @{ target *-*-* @} @var{line} @} */
933 It may be necessary to check that an expression is an integer constant
934 expression and has a certain value. To check that @code{@var{E}} has
935 value @code{@var{V}}, an idiom similar to the following is used:
938 char x[((E) == (V) ? 1 : -1)];
941 In @file{gcc.dg} tests, @code{__typeof__} is sometimes used to make
942 assertions about the types of expressions. See, for example,
943 @file{gcc.dg/c99-condexpr-1.c}. The more subtle uses depend on the
944 exact rules for the types of conditional expressions in the C
945 standard; see, for example, @file{gcc.dg/c99-intconst-1.c}.
947 It is useful to be able to test that optimizations are being made
948 properly. This cannot be done in all cases, but it can be done where
949 the optimization will lead to code being optimized away (for example,
950 where flow analysis or alias analysis should show that certain code
951 cannot be called) or to functions not being called because they have
952 been expanded as built-in functions. Such tests go in
953 @file{gcc.c-torture/execute}. Where code should be optimized away, a
954 call to a nonexistent function such as @code{link_failure ()} may be
955 inserted; a definition
968 will also be needed so that linking still succeeds when the test is
969 run without optimization. When all calls to a built-in function
970 should have been optimized and no calls to the non-built-in version of
971 the function should remain, that function may be defined as
972 @code{static} to call @code{abort ()} (although redeclaring a function
973 as static may not work on all targets).
975 All testcases must be portable. Target-specific testcases must have
976 appropriate code to avoid causing failures on unsupported systems;
977 unfortunately, the mechanisms for this differ by directory.
979 FIXME: discuss non-C testsuites here.
981 @node Test Directives
982 @section Directives used within DejaGnu tests
985 * Directives:: Syntax and descriptions of test directives.
986 * Selectors:: Selecting targets to which a test applies.
987 * Effective-Target Keywords:: Keywords describing target attributes.
988 * Add Options:: Features for @code{dg-add-options}
989 * Require Support:: Variants of @code{dg-require-@var{support}}
990 * Final Actions:: Commands for use in @code{dg-final}
994 @subsection Syntax and Descriptions of test directives
996 Test directives appear within comments in a test source file and begin
997 with @code{dg-}. Some of these are defined within DejaGnu and others
998 are local to the GCC testsuite.
1000 The order in which test directives appear in a test can be important:
1001 directives local to GCC sometimes override information used by the
1002 DejaGnu directives, which know nothing about the GCC directives, so the
1003 DejaGnu directives must precede GCC directives.
1005 Several test directives include selectors (@pxref{Selectors, , })
1006 which are usually preceded by the keyword @code{target} or @code{xfail}.
1008 @subsubsection Specify how to build the test
1011 @item @{ dg-do @var{do-what-keyword} [@{ target/xfail @var{selector} @}] @}
1012 @var{do-what-keyword} specifies how the test is compiled and whether
1013 it is executed. It is one of:
1017 Compile with @option{-E} to run only the preprocessor.
1019 Compile with @option{-S} to produce an assembly code file.
1021 Compile with @option{-c} to produce a relocatable object file.
1023 Compile, assemble, and link to produce an executable file.
1025 Produce and run an executable file, which is expected to return
1029 The default is @code{compile}. That can be overridden for a set of
1030 tests by redefining @code{dg-do-what-default} within the @code{.exp}
1031 file for those tests.
1033 If the directive includes the optional @samp{@{ target @var{selector} @}}
1034 then the test is skipped unless the target system matches the
1037 If @var{do-what-keyword} is @code{run} and the directive includes
1038 the optional @samp{@{ xfail @var{selector} @}} and the selector is met
1039 then the test is expected to fail. The @code{xfail} clause is ignored
1040 for other values of @var{do-what-keyword}; those tests can use
1041 directive @code{dg-xfail-if}.
1044 @subsubsection Specify additional compiler options
1047 @item @{ dg-options @var{options} [@{ target @var{selector} @}] @}
1048 This DejaGnu directive provides a list of compiler options, to be used
1049 if the target system matches @var{selector}, that replace the default
1050 options used for this set of tests.
1052 @item @{ dg-add-options @var{feature} @dots{} @}
1053 Add any compiler options that are needed to access certain features.
1054 This directive does nothing on targets that enable the features by
1055 default, or that don't provide them at all. It must come after
1056 all @code{dg-options} directives.
1057 For supported values of @var{feature} see @ref{Add Options, ,}.
1059 @item @{ dg-additional-options @var{options} [@{ target @var{selector} @}] @}
1060 This directive provides a list of compiler options, to be used
1061 if the target system matches @var{selector}, that are added to the default
1062 options used for this set of tests.
1065 @subsubsection Modify the test timeout value
1067 The normal timeout limit, in seconds, is found by searching the
1071 @item the value defined by an earlier @code{dg-timeout} directive in
1074 @item variable @var{tool_timeout} defined by the set of tests
1076 @item @var{gcc},@var{timeout} set in the target board
1082 @item @{ dg-timeout @var{n} [@{target @var{selector} @}] @}
1083 Set the time limit for the compilation and for the execution of the test
1084 to the specified number of seconds.
1086 @item @{ dg-timeout-factor @var{x} [@{ target @var{selector} @}] @}
1087 Multiply the normal time limit for compilation and execution of the test
1088 by the specified floating-point factor.
1091 @subsubsection Skip a test for some targets
1094 @item @{ dg-skip-if @var{comment} @{ @var{selector} @} [@{ @var{include-opts} @} [@{ @var{exclude-opts} @}]] @}
1095 Arguments @var{include-opts} and @var{exclude-opts} are lists in which
1096 each element is a string of zero or more GCC options.
1097 Skip the test if all of the following conditions are met:
1099 @item the test system is included in @var{selector}
1101 @item for at least one of the option strings in @var{include-opts},
1102 every option from that string is in the set of options with which
1103 the test would be compiled; use @samp{"*"} for an @var{include-opts} list
1104 that matches any options; that is the default if @var{include-opts} is
1107 @item for each of the option strings in @var{exclude-opts}, at least one
1108 option from that string is not in the set of options with which the test
1109 would be compiled; use @samp{""} for an empty @var{exclude-opts} list;
1110 that is the default if @var{exclude-opts} is not specified
1113 For example, to skip a test if option @code{-Os} is present:
1116 /* @{ dg-skip-if "" @{ *-*-* @} @{ "-Os" @} @{ "" @} @} */
1119 To skip a test if both options @code{-O2} and @code{-g} are present:
1122 /* @{ dg-skip-if "" @{ *-*-* @} @{ "-O2 -g" @} @{ "" @} @} */
1125 To skip a test if either @code{-O2} or @code{-O3} is present:
1128 /* @{ dg-skip-if "" @{ *-*-* @} @{ "-O2" "-O3" @} @{ "" @} @} */
1131 To skip a test unless option @code{-Os} is present:
1134 /* @{ dg-skip-if "" @{ *-*-* @} @{ "*" @} @{ "-Os" @} @} */
1137 To skip a test if either @code{-O2} or @code{-O3} is used with @code{-g}
1138 but not if @code{-fpic} is also present:
1141 /* @{ dg-skip-if "" @{ *-*-* @} @{ "-O2 -g" "-O3 -g" @} @{ "-fpic" @} @} */
1144 @item @{ dg-require-effective-target @var{keyword} [@{ @var{selector} @}] @}
1145 Skip the test if the test target, including current multilib flags,
1146 is not covered by the effective-target keyword.
1147 If the directive includes the optional @samp{@{ @var{selector} @}}
1148 then the effective-target test is only performed if the target system
1149 matches the @var{selector}.
1150 This directive must appear after any @code{dg-do} directive in the test
1151 and before any @code{dg-additional-sources} directive.
1152 @xref{Effective-Target Keywords, , }.
1154 @item @{ dg-require-@var{support} args @}
1155 Skip the test if the target does not provide the required support.
1156 These directives must appear after any @code{dg-do} directive in the test
1157 and before any @code{dg-additional-sources} directive.
1158 They require at least one argument, which can be an empty string if the
1159 specific procedure does not examine the argument.
1160 @xref{Require Support, , }, for a complete list of these directives.
1163 @subsubsection Expect a test to fail for some targets
1166 @item @{ dg-xfail-if @var{comment} @{ @var{selector} @} [@{ @var{include-opts} @} [@{ @var{exclude-opts} @}]] @}
1167 Expect the test to fail if the conditions (which are the same as for
1168 @code{dg-skip-if}) are met. This does not affect the execute step.
1170 @item @{ dg-xfail-run-if @var{comment} @{ @var{selector} @} [@{ @var{include-opts} @} [@{ @var{exclude-opts} @}]] @}
1171 Expect the execute step of a test to fail if the conditions (which are
1172 the same as for @code{dg-skip-if}) are met.
1175 @subsubsection Expect the test executable to fail
1178 @item @{ dg-shouldfail @var{comment} [@{ @var{selector} @} [@{ @var{include-opts} @} [@{ @var{exclude-opts} @}]]] @}
1179 Expect the test executable to return a nonzero exit status if the
1180 conditions (which are the same as for @code{dg-skip-if}) are met.
1183 @subsubsection Verify compiler messages
1184 Where @var{line} is an accepted argument for these commands, a value of @samp{0}
1185 can be used if there is no line associated with the message.
1188 @item @{ dg-error @var{regexp} [@var{comment} [@{ target/xfail @var{selector} @} [@var{line}] ]] @}
1189 This DejaGnu directive appears on a source line that is expected to get
1190 an error message, or else specifies the source line associated with the
1191 message. If there is no message for that line or if the text of that
1192 message is not matched by @var{regexp} then the check fails and
1193 @var{comment} is included in the @code{FAIL} message. The check does
1194 not look for the string @samp{error} unless it is part of @var{regexp}.
1196 @item @{ dg-warning @var{regexp} [@var{comment} [@{ target/xfail @var{selector} @} [@var{line}] ]] @}
1197 This DejaGnu directive appears on a source line that is expected to get
1198 a warning message, or else specifies the source line associated with the
1199 message. If there is no message for that line or if the text of that
1200 message is not matched by @var{regexp} then the check fails and
1201 @var{comment} is included in the @code{FAIL} message. The check does
1202 not look for the string @samp{warning} unless it is part of @var{regexp}.
1204 @item @{ dg-message @var{regexp} [@var{comment} [@{ target/xfail @var{selector} @} [@var{line}] ]] @}
1205 The line is expected to get a message other than an error or warning.
1206 If there is no message for that line or if the text of that message is
1207 not matched by @var{regexp} then the check fails and @var{comment} is
1208 included in the @code{FAIL} message.
1210 @item @{ dg-bogus @var{regexp} [@var{comment} [@{ target/xfail @var{selector} @} [@var{line}] ]] @}
1211 This DejaGnu directive appears on a source line that should not get a
1212 message matching @var{regexp}, or else specifies the source line
1213 associated with the bogus message. It is usually used with @samp{xfail}
1214 to indicate that the message is a known problem for a particular set of
1217 @item @{ dg-line @var{linenumvar} @}
1218 This DejaGnu directive sets the variable @var{linenumvar} to the line number of
1219 the source line. The variable @var{linenumvar} can then be used in subsequent
1220 @code{dg-error}, @code{dg-warning}, @code{dg-message} and @code{dg-bogus}
1221 directives. For example:
1224 int a; /* @{ dg-line first_def_a @} */
1225 float a; /* @{ dg-error "conflicting types of" @} */
1226 /* @{ dg-message "previous declaration of" "" @{ target *-*-* @} first_def_a @} */
1229 @item @{ dg-excess-errors @var{comment} [@{ target/xfail @var{selector} @}] @}
1230 This DejaGnu directive indicates that the test is expected to fail due
1231 to compiler messages that are not handled by @samp{dg-error},
1232 @samp{dg-warning} or @samp{dg-bogus}. For this directive @samp{xfail}
1233 has the same effect as @samp{target}.
1235 @item @{ dg-prune-output @var{regexp} @}
1236 Prune messages matching @var{regexp} from the test output.
1239 @subsubsection Verify output of the test executable
1242 @item @{ dg-output @var{regexp} [@{ target/xfail @var{selector} @}] @}
1243 This DejaGnu directive compares @var{regexp} to the combined output
1244 that the test executable writes to @file{stdout} and @file{stderr}.
1247 @subsubsection Specify environment variables for a test
1250 @item @{ dg-set-compiler-env-var @var{var_name} "@var{var_value}" @}
1251 Specify that the environment variable @var{var_name} needs to be set
1252 to @var{var_value} before invoking the compiler on the test file.
1254 @item @{ dg-set-target-env-var @var{var_name} "@var{var_value}" @}
1255 Specify that the environment variable @var{var_name} needs to be set
1256 to @var{var_value} before execution of the program created by the test.
1259 @subsubsection Specify additional files for a test
1262 @item @{ dg-additional-files "@var{filelist}" @}
1263 Specify additional files, other than source files, that must be copied
1264 to the system where the compiler runs.
1266 @item @{ dg-additional-sources "@var{filelist}" @}
1267 Specify additional source files to appear in the compile line
1268 following the main test file.
1271 @subsubsection Add checks at the end of a test
1274 @item @{ dg-final @{ @var{local-directive} @} @}
1275 This DejaGnu directive is placed within a comment anywhere in the
1276 source file and is processed after the test has been compiled and run.
1277 Multiple @samp{dg-final} commands are processed in the order in which
1278 they appear in the source file. @xref{Final Actions, , }, for a list
1279 of directives that can be used within @code{dg-final}.
1283 @subsection Selecting targets to which a test applies
1285 Several test directives include @var{selector}s to limit the targets
1286 for which a test is run or to declare that a test is expected to fail
1287 on particular targets.
1291 @item one or more target triplets, possibly including wildcard characters;
1292 use @samp{*-*-*} to match any target
1293 @item a single effective-target keyword (@pxref{Effective-Target Keywords})
1294 @item a logical expression
1297 Depending on the context, the selector specifies whether a test is
1298 skipped and reported as unsupported or is expected to fail. A context
1299 that allows either @samp{target} or @samp{xfail} also allows
1300 @samp{@{ target @var{selector1} xfail @var{selector2} @}}
1301 to skip the test for targets that don't match @var{selector1} and the
1302 test to fail for targets that match @var{selector2}.
1304 A selector expression appears within curly braces and uses a single
1305 logical operator: one of @samp{!}, @samp{&&}, or @samp{||}. An
1306 operand is another selector expression, an effective-target keyword,
1307 a single target triplet, or a list of target triplets within quotes or
1308 curly braces. For example:
1311 @{ target @{ ! "hppa*-*-* ia64*-*-*" @} @}
1312 @{ target @{ powerpc*-*-* && lp64 @} @}
1313 @{ xfail @{ lp64 || vect_no_align @} @}
1316 @node Effective-Target Keywords
1317 @subsection Keywords describing target attributes
1319 Effective-target keywords identify sets of targets that support
1320 particular functionality. They are used to limit tests to be run only
1321 for particular targets, or to specify that particular sets of targets
1322 are expected to fail some tests.
1324 Effective-target keywords are defined in @file{lib/target-supports.exp} in
1325 the GCC testsuite, with the exception of those that are documented as
1326 being local to a particular test directory.
1328 The @samp{effective target} takes into account all of the compiler options
1329 with which the test will be compiled, including the multilib options.
1330 By convention, keywords ending in @code{_nocache} can also include options
1331 specified for the particular test in an earlier @code{dg-options} or
1332 @code{dg-add-options} directive.
1334 @subsubsection Endianness
1338 Target uses big-endian memory order for multi-byte and multi-word data.
1341 Target uses little-endian memory order for multi-byte and multi-word data.
1344 @subsubsection Data type sizes
1348 Target has 32-bit @code{int}, @code{long}, and pointers.
1351 Target has 32-bit @code{int}, 64-bit @code{long} and pointers.
1354 Target has 32-bit @code{int} and @code{long}, 64-bit @code{long long}
1358 Target has 64-bit @code{double}.
1361 Target has @code{double} that is 64 bits or longer.
1364 Target has 128-bit @code{long double}.
1367 Target has @code{int} that is at 32 bits or longer.
1370 Target has @code{int} that is 16 bits or shorter.
1373 Target has 64-bit @code{long long}.
1376 Target has @code{int} and @code{long} with different sizes.
1379 Target has @code{short} and @code{int} with the same size.
1382 Target has pointers (@code{void *}) and @code{short} with the same size.
1385 Target has @code{int} and @code{float} with the same size.
1388 Target has pointers (@code{void *}) and @code{long} with the same size.
1391 Target supports @code{double} that is longer than @code{float}.
1393 @item large_long_double
1394 Target supports @code{long double} that is longer than @code{double}.
1397 Target has pointers that are 32 bits or longer.
1400 Target has a 20-bit or larger address space, so supports at least
1401 16-bit array and structure sizes.
1404 Target has a 24-bit or larger address space, so supports at least
1405 20-bit array and structure sizes.
1408 Target has a 32-bit or larger address space, so supports at least
1409 24-bit array and structure sizes.
1412 Target has @code{wchar_t} that is at least 4 bytes.
1415 Target has the @code{_Float@var{n}} type.
1418 Target has the @code{_Float@var{n}x} type.
1420 @item float@var{n}_runtime
1421 Target has the @code{_Float@var{n}} type, including runtime support
1422 for any options added with @code{dg-add-options}.
1424 @item float@var{n}x_runtime
1425 Target has the @code{_Float@var{n}x} type, including runtime support
1426 for any options added with @code{dg-add-options}.
1428 @item floatn_nx_runtime
1429 Target has runtime support for any options added with
1430 @code{dg-add-options} for any @code{_Float@var{n}} or
1431 @code{_Float@var{n}x} type.
1434 Target supports floating point infinite (@code{inf}) for type
1437 @subsubsection Fortran-specific attributes
1440 @item fortran_integer_16
1441 Target supports Fortran @code{integer} that is 16 bytes or longer.
1443 @item fortran_real_10
1444 Target supports Fortran @code{real} that is 10 bytes or longer.
1446 @item fortran_real_16
1447 Target supports Fortran @code{real} that is 16 bytes or longer.
1449 @item fortran_large_int
1450 Target supports Fortran @code{integer} kinds larger than @code{integer(8)}.
1452 @item fortran_large_real
1453 Target supports Fortran @code{real} kinds larger than @code{real(8)}.
1456 @subsubsection Vector-specific attributes
1459 @item vect_align_stack_vars
1460 The target's ABI allows stack variables to be aligned to the preferred
1464 Target supports both signed and unsigned averaging operations on vectors
1467 @item vect_mulhrs_hi
1468 Target supports both signed and unsigned multiply-high-with-round-and-scale
1469 operations on vectors of half-words.
1471 @item vect_sdiv_pow2_si
1472 Target supports signed division by constant power-of-2 operations
1473 on vectors of 4-byte integers.
1475 @item vect_condition
1476 Target supports vector conditional operations.
1478 @item vect_cond_mixed
1479 Target supports vector conditional operations where comparison operands
1480 have different type from the value operands.
1483 Target supports hardware vectors of @code{double}.
1485 @item vect_double_cond_arith
1486 Target supports conditional addition, subtraction, multiplication,
1487 division, minimum and maximum on vectors of @code{double}, via the
1488 @code{cond_} optabs.
1490 @item vect_element_align_preferred
1491 The target's preferred vector alignment is the same as the element
1495 Target supports hardware vectors of @code{float} when
1496 @option{-funsafe-math-optimizations} is in effect.
1498 @item vect_float_strict
1499 Target supports hardware vectors of @code{float} when
1500 @option{-funsafe-math-optimizations} is not in effect.
1501 This implies @code{vect_float}.
1504 Target supports hardware vectors of @code{int}.
1507 Target supports hardware vectors of @code{long}.
1509 @item vect_long_long
1510 Target supports hardware vectors of @code{long long}.
1512 @item vect_check_ptrs
1513 Target supports the @code{check_raw_ptrs} and @code{check_war_ptrs}
1516 @item vect_fully_masked
1517 Target supports fully-masked (also known as fully-predicated) loops,
1518 so that vector loops can handle partial as well as full vectors.
1520 @item vect_masked_store
1521 Target supports vector masked stores.
1523 @item vect_scatter_store
1524 Target supports vector scatter stores.
1526 @item vect_aligned_arrays
1527 Target aligns arrays to vector alignment boundary.
1529 @item vect_hw_misalign
1530 Target supports a vector misalign access.
1533 Target does not support a vector alignment mechanism.
1535 @item vect_peeling_profitable
1536 Target might require to peel loops for alignment purposes.
1538 @item vect_no_int_min_max
1539 Target does not support a vector min and max instruction on @code{int}.
1541 @item vect_no_int_add
1542 Target does not support a vector add instruction on @code{int}.
1544 @item vect_no_bitwise
1545 Target does not support vector bitwise instructions.
1548 Target supports comparison of @code{bool} vectors for at least one
1552 Target supports addition of @code{char} vectors for at least one
1555 @item vect_char_mult
1556 Target supports @code{vector char} multiplication.
1558 @item vect_short_mult
1559 Target supports @code{vector short} multiplication.
1562 Target supports @code{vector int} multiplication.
1564 @item vect_long_mult
1565 Target supports 64 bit @code{vector long} multiplication.
1567 @item vect_extract_even_odd
1568 Target supports vector even/odd element extraction.
1570 @item vect_extract_even_odd_wide
1571 Target supports vector even/odd element extraction of vectors with elements
1572 @code{SImode} or larger.
1574 @item vect_interleave
1575 Target supports vector interleaving.
1578 Target supports vector interleaving and extract even/odd.
1580 @item vect_strided_wide
1581 Target supports vector interleaving and extract even/odd for wide
1585 Target supports vector permutation.
1587 @item vect_perm_byte
1588 Target supports permutation of vectors with 8-bit elements.
1590 @item vect_perm_short
1591 Target supports permutation of vectors with 16-bit elements.
1593 @item vect_perm3_byte
1594 Target supports permutation of vectors with 8-bit elements, and for the
1595 default vector length it is possible to permute:
1597 @{ a0, a1, a2, b0, b1, b2, @dots{} @}
1601 @{ a0, a0, a0, b0, b0, b0, @dots{} @}
1602 @{ a1, a1, a1, b1, b1, b1, @dots{} @}
1603 @{ a2, a2, a2, b2, b2, b2, @dots{} @}
1605 using only two-vector permutes, regardless of how long the sequence is.
1607 @item vect_perm3_int
1608 Like @code{vect_perm3_byte}, but for 32-bit elements.
1610 @item vect_perm3_short
1611 Like @code{vect_perm3_byte}, but for 16-bit elements.
1614 Target supports a hardware vector shift operation.
1616 @item vect_unaligned_possible
1617 Target prefers vectors to have an alignment greater than element
1618 alignment, but also allows unaligned vector accesses in some
1621 @item vect_variable_length
1622 Target has variable-length vectors.
1624 @item vect_widen_sum_hi_to_si
1625 Target supports a vector widening summation of @code{short} operands
1626 into @code{int} results, or can promote (unpack) from @code{short}
1629 @item vect_widen_sum_qi_to_hi
1630 Target supports a vector widening summation of @code{char} operands
1631 into @code{short} results, or can promote (unpack) from @code{char}
1634 @item vect_widen_sum_qi_to_si
1635 Target supports a vector widening summation of @code{char} operands
1636 into @code{int} results.
1638 @item vect_widen_mult_qi_to_hi
1639 Target supports a vector widening multiplication of @code{char} operands
1640 into @code{short} results, or can promote (unpack) from @code{char} to
1641 @code{short} and perform non-widening multiplication of @code{short}.
1643 @item vect_widen_mult_hi_to_si
1644 Target supports a vector widening multiplication of @code{short} operands
1645 into @code{int} results, or can promote (unpack) from @code{short} to
1646 @code{int} and perform non-widening multiplication of @code{int}.
1648 @item vect_widen_mult_si_to_di_pattern
1649 Target supports a vector widening multiplication of @code{int} operands
1650 into @code{long} results.
1653 Target supports a vector dot-product of @code{signed char}.
1656 Target supports a vector dot-product of @code{unsigned char}.
1659 Target supports a vector dot-product of @code{signed short}.
1662 Target supports a vector dot-product of @code{unsigned short}.
1664 @item vect_pack_trunc
1665 Target supports a vector demotion (packing) of @code{short} to @code{char}
1666 and from @code{int} to @code{short} using modulo arithmetic.
1669 Target supports a vector promotion (unpacking) of @code{char} to @code{short}
1670 and from @code{char} to @code{int}.
1672 @item vect_intfloat_cvt
1673 Target supports conversion from @code{signed int} to @code{float}.
1675 @item vect_uintfloat_cvt
1676 Target supports conversion from @code{unsigned int} to @code{float}.
1678 @item vect_floatint_cvt
1679 Target supports conversion from @code{float} to @code{signed int}.
1681 @item vect_floatuint_cvt
1682 Target supports conversion from @code{float} to @code{unsigned int}.
1684 @item vect_intdouble_cvt
1685 Target supports conversion from @code{signed int} to @code{double}.
1687 @item vect_doubleint_cvt
1688 Target supports conversion from @code{double} to @code{signed int}.
1690 @item vect_max_reduc
1691 Target supports max reduction for vectors.
1693 @item vect_sizes_16B_8B
1694 Target supports 16- and 8-bytes vectors.
1696 @item vect_sizes_32B_16B
1697 Target supports 32- and 16-bytes vectors.
1699 @item vect_logical_reduc
1700 Target supports AND, IOR and XOR reduction on vectors.
1702 @item vect_fold_extract_last
1703 Target supports the @code{fold_extract_last} optab.
1706 @subsubsection Thread Local Storage attributes
1710 Target supports thread-local storage.
1713 Target supports native (rather than emulated) thread-local storage.
1716 Test system supports executing TLS executables.
1719 @subsubsection Decimal floating point attributes
1723 Targets supports compiling decimal floating point extension to C.
1726 Including the options used to compile this particular test, the
1727 target supports compiling decimal floating point extension to C.
1730 Test system can execute decimal floating point tests.
1733 Including the options used to compile this particular test, the
1734 test system can execute decimal floating point tests.
1737 Target generates decimal floating point instructions with current options.
1740 @subsubsection ARM-specific attributes
1744 ARM target generates 32-bit code.
1746 @item arm_little_endian
1747 ARM target that generates little-endian code.
1750 ARM target adheres to the ABI for the ARM Architecture.
1754 ARM target defines @code{__ARM_FP} using @code{-mfloat-abi=softfp} or
1755 equivalent options. Some multilibs may be incompatible with these
1759 @anchor{arm_fp_dp_ok}
1760 ARM target defines @code{__ARM_FP} with double-precision support using
1761 @code{-mfloat-abi=softfp} or equivalent options. Some multilibs may
1762 be incompatible with these options.
1765 ARM target adheres to the VFP and Advanced SIMD Register Arguments
1766 variant of the ABI for the ARM Architecture (as selected with
1767 @code{-mfloat-abi=hard}).
1770 ARM target uses the soft-float ABI with no floating-point instructions
1771 used whatsoever (as selected with @code{-mfloat-abi=soft}).
1773 @item arm_hard_vfp_ok
1774 ARM target supports @code{-mfpu=vfp -mfloat-abi=hard}.
1775 Some multilibs may be incompatible with these options.
1778 ARM target supports @code{-mcpu=iwmmxt}.
1779 Some multilibs may be incompatible with this option.
1782 ARM target supports generating NEON instructions.
1784 @item arm_tune_string_ops_prefer_neon
1785 Test CPU tune supports inlining string operations with NEON instructions.
1788 Test system supports executing NEON instructions.
1791 Test system supports executing NEON v2 instructions.
1794 @anchor{arm_neon_ok}
1795 ARM Target supports @code{-mfpu=neon -mfloat-abi=softfp} or compatible
1796 options. Some multilibs may be incompatible with these options.
1798 @item arm_neon_ok_no_float_abi
1799 @anchor{arm_neon_ok_no_float_abi}
1800 ARM Target supports NEON with @code{-mfpu=neon}, but without any
1801 -mfloat-abi= option. Some multilibs may be incompatible with this
1805 @anchor{arm_neonv2_ok}
1806 ARM Target supports @code{-mfpu=neon-vfpv4 -mfloat-abi=softfp} or compatible
1807 options. Some multilibs may be incompatible with these options.
1810 @anchor{arm_fp16_ok}
1811 Target supports options to generate VFP half-precision floating-point
1812 instructions. Some multilibs may be incompatible with these
1813 options. This test is valid for ARM only.
1816 Target supports executing VFP half-precision floating-point
1817 instructions. This test is valid for ARM only.
1819 @item arm_neon_fp16_ok
1820 @anchor{arm_neon_fp16_ok}
1821 ARM Target supports @code{-mfpu=neon-fp16 -mfloat-abi=softfp} or compatible
1822 options, including @code{-mfp16-format=ieee} if necessary to obtain the
1823 @code{__fp16} type. Some multilibs may be incompatible with these options.
1825 @item arm_neon_fp16_hw
1826 Test system supports executing Neon half-precision float instructions.
1829 @item arm_fp16_alternative_ok
1830 ARM target supports the ARM FP16 alternative format. Some multilibs
1831 may be incompatible with the options needed.
1833 @item arm_fp16_none_ok
1834 ARM target supports specifying none as the ARM FP16 format.
1837 ARM target generates Thumb-1 code for @code{-mthumb}.
1840 ARM target generates Thumb-2 code for @code{-mthumb}.
1843 ARM target that is not using Thumb.
1846 ARM target supports @code{-mfpu=vfp -mfloat-abi=softfp}.
1847 Some multilibs may be incompatible with these options.
1850 @anchor{arm_vfp3_ok}
1851 ARM target supports @code{-mfpu=vfp3 -mfloat-abi=softfp}.
1852 Some multilibs may be incompatible with these options.
1854 @item arm_arch_v8a_hard_ok
1855 @anchor{arm_arch_v8a_hard_ok}
1856 The compiler is targeting @code{arm*-*-*} and can compile and assemble code
1857 using the options @code{-march=armv8-a -mfpu=neon-fp-armv8 -mfloat-abi=hard}.
1858 This is not enough to guarantee that linking works.
1860 @item arm_arch_v8a_hard_multilib
1861 The compiler is targeting @code{arm*-*-*} and can build programs using
1862 the options @code{-march=armv8-a -mfpu=neon-fp-armv8 -mfloat-abi=hard}.
1863 The target can also run the resulting binaries.
1866 ARM target supports @code{-mfpu=fp-armv8 -mfloat-abi=softfp}.
1867 Some multilibs may be incompatible with these options.
1869 @item arm_v8_neon_ok
1870 ARM target supports @code{-mfpu=neon-fp-armv8 -mfloat-abi=softfp}.
1871 Some multilibs may be incompatible with these options.
1873 @item arm_v8_1a_neon_ok
1874 @anchor{arm_v8_1a_neon_ok}
1875 ARM target supports options to generate ARMv8.1-A Adv.SIMD instructions.
1876 Some multilibs may be incompatible with these options.
1878 @item arm_v8_1a_neon_hw
1879 ARM target supports executing ARMv8.1-A Adv.SIMD instructions. Some
1880 multilibs may be incompatible with the options needed. Implies
1884 ARM target supports acquire-release instructions.
1886 @item arm_v8_2a_fp16_scalar_ok
1887 @anchor{arm_v8_2a_fp16_scalar_ok}
1888 ARM target supports options to generate instructions for ARMv8.2-A and
1889 scalar instructions from the FP16 extension. Some multilibs may be
1890 incompatible with these options.
1892 @item arm_v8_2a_fp16_scalar_hw
1893 ARM target supports executing instructions for ARMv8.2-A and scalar
1894 instructions from the FP16 extension. Some multilibs may be
1895 incompatible with these options. Implies arm_v8_2a_fp16_neon_ok.
1897 @item arm_v8_2a_fp16_neon_ok
1898 @anchor{arm_v8_2a_fp16_neon_ok}
1899 ARM target supports options to generate instructions from ARMv8.2-A with
1900 the FP16 extension. Some multilibs may be incompatible with these
1901 options. Implies arm_v8_2a_fp16_scalar_ok.
1903 @item arm_v8_2a_fp16_neon_hw
1904 ARM target supports executing instructions from ARMv8.2-A with the FP16
1905 extension. Some multilibs may be incompatible with these options.
1906 Implies arm_v8_2a_fp16_neon_ok and arm_v8_2a_fp16_scalar_hw.
1908 @item arm_v8_2a_dotprod_neon_ok
1909 @anchor{arm_v8_2a_dotprod_neon_ok}
1910 ARM target supports options to generate instructions from ARMv8.2-A with
1911 the Dot Product extension. Some multilibs may be incompatible with these
1914 @item arm_v8_2a_dotprod_neon_hw
1915 ARM target supports executing instructions from ARMv8.2-A with the Dot
1916 Product extension. Some multilibs may be incompatible with these options.
1917 Implies arm_v8_2a_dotprod_neon_ok.
1919 @item arm_fp16fml_neon_ok
1920 @anchor{arm_fp16fml_neon_ok}
1921 ARM target supports extensions to generate the @code{VFMAL} and @code{VFMLS}
1922 half-precision floating-point instructions available from ARMv8.2-A and
1923 onwards. Some multilibs may be incompatible with these options.
1925 @item arm_v8_2a_bf16_neon_ok
1926 ARM target supports options to generate instructions from ARMv8.2-A with
1927 the BFloat16 extension (bf16). Some multilibs may be incompatible with these
1930 @item arm_v8_2a_i8mm_ok
1931 ARM target supports options to generate instructions from ARMv8.2-A with
1932 the 8-Bit Integer Matrix Multiply extension (i8mm). Some multilibs may be
1933 incompatible with these options.
1935 @item arm_v8_1m_mve_ok
1936 ARM target supports options to generate instructions from ARMv8.1-M with
1937 the M-Profile Vector Extension (MVE). Some multilibs may be incompatible
1940 @item arm_v8_1m_mve_fp_ok
1941 ARM target supports options to generate instructions from ARMv8.1-M with
1942 the Half-precision floating-point instructions (HP), Floating-point Extension
1943 (FP) along with M-Profile Vector Extension (MVE). Some multilibs may be
1944 incompatible with these options.
1947 Test system supports executing MVE instructions.
1949 @item arm_v8m_main_cde
1950 ARM target supports options to generate instructions from ARMv8-M with
1951 the Custom Datapath Extension (CDE). Some multilibs may be incompatible
1954 @item arm_v8m_main_cde_fp
1955 ARM target supports options to generate instructions from ARMv8-M with
1956 the Custom Datapath Extension (CDE) and floating-point (VFP).
1957 Some multilibs may be incompatible with these options.
1959 @item arm_v8_1m_main_cde_mve
1960 ARM target supports options to generate instructions from ARMv8.1-M with
1961 the Custom Datapath Extension (CDE) and M-Profile Vector Extension (MVE).
1962 Some multilibs may be incompatible with these options.
1964 @item arm_prefer_ldrd_strd
1965 ARM target prefers @code{LDRD} and @code{STRD} instructions over
1966 @code{LDM} and @code{STM} instructions.
1968 @item arm_thumb1_movt_ok
1969 ARM target generates Thumb-1 code for @code{-mthumb} with @code{MOVW}
1970 and @code{MOVT} instructions available.
1972 @item arm_thumb1_cbz_ok
1973 ARM target generates Thumb-1 code for @code{-mthumb} with
1974 @code{CBZ} and @code{CBNZ} instructions available.
1976 @item arm_divmod_simode
1977 ARM target for which divmod transform is disabled, if it supports hardware
1981 ARM target supports ARMv8-M Security Extensions, enabled by the @code{-mcmse}
1984 @item arm_coproc1_ok
1985 @anchor{arm_coproc1_ok}
1986 ARM target supports the following coprocessor instructions: @code{CDP},
1987 @code{LDC}, @code{STC}, @code{MCR} and @code{MRC}.
1989 @item arm_coproc2_ok
1990 @anchor{arm_coproc2_ok}
1991 ARM target supports all the coprocessor instructions also listed as supported
1992 in @ref{arm_coproc1_ok} in addition to the following: @code{CDP2}, @code{LDC2},
1993 @code{LDC2l}, @code{STC2}, @code{STC2l}, @code{MCR2} and @code{MRC2}.
1995 @item arm_coproc3_ok
1996 @anchor{arm_coproc3_ok}
1997 ARM target supports all the coprocessor instructions also listed as supported
1998 in @ref{arm_coproc2_ok} in addition the following: @code{MCRR} and @code{MRRC}.
2000 @item arm_coproc4_ok
2001 ARM target supports all the coprocessor instructions also listed as supported
2002 in @ref{arm_coproc3_ok} in addition the following: @code{MCRR2} and @code{MRRC2}.
2005 @anchor{arm_simd32_ok}
2006 ARM Target supports options suitable for accessing the SIMD32 intrinsics from
2008 Some multilibs may be incompatible with these options.
2011 @anchor{arm_qbit_ok}
2012 ARM Target supports options suitable for accessing the Q-bit manipulation
2013 intrinsics from @code{arm_acle.h}.
2014 Some multilibs may be incompatible with these options.
2017 @anchor{arm_softfp_ok}
2018 ARM target supports the @code{-mfloat-abi=softfp} option.
2021 @anchor{arm_hard_ok}
2022 ARM target supports the @code{-mfloat-abi=hard} option.
2024 @item arm_v8_1_lob_ok
2025 @anchor{arm_v8_1_lob_ok}
2026 ARM Target supports executing the Armv8.1-M Mainline Low Overhead Loop
2027 instructions @code{DLS} and @code{LE}.
2028 Some multilibs may be incompatible with these options.
2030 @item arm_thumb2_ok_no_arm_v8_1_lob
2031 ARM target generates Thumb-2 code for @code{-mthumb} but does not
2032 support executing the Armv8.1-M Mainline Low Overhead Loop
2033 instructions @code{DLS} and @code{LE}.
2037 @subsubsection AArch64-specific attributes
2040 @item aarch64_asm_<ext>_ok
2041 AArch64 assembler supports the architecture extension @code{ext} via the
2042 @code{.arch_extension} pseudo-op.
2044 AArch64 target which generates instruction sequences for tiny memory model.
2046 AArch64 target which generates instruction sequences for small memory model.
2048 AArch64 target which generates instruction sequences for large memory model.
2049 @item aarch64_little_endian
2050 AArch64 target which generates instruction sequences for little endian.
2051 @item aarch64_big_endian
2052 AArch64 target which generates instruction sequences for big endian.
2053 @item aarch64_small_fpic
2054 Binutils installed on test system supports relocation types required by -fpic
2055 for AArch64 small memory model.
2056 @item aarch64_sve_hw
2057 AArch64 target that is able to generate and execute SVE code (regardless of
2058 whether it does so by default).
2059 @item aarch64_sve128_hw
2060 @itemx aarch64_sve256_hw
2061 @itemx aarch64_sve512_hw
2062 @itemx aarch64_sve1024_hw
2063 @itemx aarch64_sve2048_hw
2064 Like @code{aarch64_sve_hw}, but also test for an exact hardware vector length.
2066 @item aarch64_fjcvtzs_hw
2067 AArch64 target that is able to generate and execute armv8.3-a FJCVTZS
2071 @subsubsection MIPS-specific attributes
2075 MIPS target supports 64-bit instructions.
2078 MIPS target does not produce MIPS16 code.
2080 @item mips16_attribute
2081 MIPS target can generate MIPS16 code.
2084 MIPS target is a Loongson-2E or -2F target using an ABI that supports
2085 the Loongson vector modes.
2088 MIPS target supports @code{-mmsa}, MIPS SIMD Architecture (MSA).
2090 @item mips_newabi_large_long_double
2091 MIPS target supports @code{long double} larger than @code{double}
2092 when using the new ABI.
2094 @item mpaired_single
2095 MIPS target supports @code{-mpaired-single}.
2098 @subsubsection MSP430-specific attributes
2102 MSP430 target has the small memory model enabled (@code{-msmall}).
2105 MSP430 target has the large memory model enabled (@code{-mlarge}).
2108 @subsubsection PowerPC-specific attributes
2113 PowerPC target supports executing hardware DFP instructions.
2116 PowerPC target supports executing VSX instructions (ISA 2.07).
2119 Test system supports executing 64-bit instructions.
2121 @item powerpc_altivec
2122 PowerPC target supports AltiVec.
2124 @item powerpc_altivec_ok
2125 PowerPC target supports @code{-maltivec}.
2127 @item powerpc_eabi_ok
2128 PowerPC target supports @code{-meabi}.
2131 PowerPC target supports @code{-mabi=elfv2}.
2134 PowerPC target supports floating-point registers.
2136 @item powerpc_hard_double
2137 PowerPC target supports hardware double-precision floating-point.
2139 @item powerpc_htm_ok
2140 PowerPC target supports @code{-mhtm}
2142 @item powerpc_p8vector_ok
2143 PowerPC target supports @code{-mpower8-vector}
2145 @item powerpc_popcntb_ok
2146 PowerPC target supports the @code{popcntb} instruction, indicating
2147 that this target supports @code{-mcpu=power5}.
2149 @item powerpc_ppu_ok
2150 PowerPC target supports @code{-mcpu=cell}.
2153 PowerPC target supports PowerPC SPE.
2155 @item powerpc_spe_nocache
2156 Including the options used to compile this particular test, the
2157 PowerPC target supports PowerPC SPE.
2160 PowerPC target supports PowerPC SPU.
2162 @item powerpc_vsx_ok
2163 PowerPC target supports @code{-mvsx}.
2165 @item powerpc_405_nocache
2166 Including the options used to compile this particular test, the
2167 PowerPC target supports PowerPC 405.
2170 PowerPC target supports executing reciprocal estimate instructions.
2173 PowerPC target supports executing AltiVec instructions.
2176 PowerPC target supports executing VSX instructions (ISA 2.06).
2179 @subsubsection Other hardware attributes
2181 @c Please keep this table sorted alphabetically.
2184 Target supports autoincrement/decrement addressing.
2187 Target supports compiling @code{avx} instructions.
2190 Target supports the execution of @code{avx} instructions.
2193 Target supports compiling @code{avx2} instructions.
2196 Target supports the execution of @code{avx2} instructions.
2199 Target supports compiling @code{avx512f} instructions.
2201 @item avx512f_runtime
2202 Target supports the execution of @code{avx512f} instructions.
2204 @item avx512vp2intersect
2205 Target supports the execution of @code{avx512vp2intersect} instructions.
2208 Test system can execute AltiVec and Cell PPU instructions.
2211 Target uses a ColdFire FPU.
2214 Target supporting hardware divmod insn or divmod libcall.
2217 Target supporting hardware divmod insn or divmod libcall for SImode.
2220 Target supports FPU instructions.
2222 @item non_strict_align
2223 Target does not require strict alignment.
2226 The x86-64 target linker supports PIE with copy reloc.
2229 Target supports x86 @code{rdrand} instruction.
2232 Target has a square root instruction that the compiler can generate.
2235 Target supports compiling @code{sse} instructions.
2238 Target supports the execution of @code{sse} instructions.
2241 Target supports compiling @code{sse2} instructions.
2244 Target supports the execution of @code{sse2} instructions.
2246 @item sync_char_short
2247 Target supports atomic operations on @code{char} and @code{short}.
2250 Target supports atomic operations on @code{int} and @code{long}.
2253 Test environment appears to run executables on a simulator that
2254 accepts only @code{EM_SPARC} executables and chokes on @code{EM_SPARC32PLUS}
2255 or @code{EM_SPARCV9} executables.
2257 @item vect_cmdline_needed
2258 Target requires a command line argument to enable a SIMD instruction set.
2261 Target supports the xorsign optab expansion.
2265 @subsubsection Environment attributes
2269 The language for the compiler under test is C.
2272 The language for the compiler under test is C++.
2275 Target provides a full C99 runtime.
2277 @item correct_iso_cpp_string_wchar_protos
2278 Target @code{string.h} and @code{wchar.h} headers provide C++ required
2279 overloads for @code{strchr} etc. functions.
2282 Target provides the D runtime.
2284 @item d_runtime_has_std_library
2285 Target provides the D standard library (Phobos).
2287 @item dummy_wcsftime
2288 Target uses a dummy @code{wcsftime} function that always returns zero.
2291 Target can truncate a file from a file descriptor, as used by
2292 @file{libgfortran/io/unix.c:fd_truncate}; i.e.@: @code{ftruncate} or
2296 Target provides @file{fenv.h} include file.
2298 @item fenv_exceptions
2299 Target supports @file{fenv.h} with all the standard IEEE exceptions
2300 and floating-point exceptions are raised by arithmetic operations.
2303 Target offers such file I/O library functions as @code{fopen},
2304 @code{fclose}, @code{tmpnam}, and @code{remove}. This is a link-time
2305 requirement for the presence of the functions in the library; even if
2306 they fail at runtime, the requirement is still regarded as satisfied.
2309 Target is @samp{freestanding} as defined in section 4 of the C99 standard.
2310 Effectively, it is a target which supports no extra headers or libraries
2311 other than what is considered essential.
2314 Target supports @code{gettimeofday}.
2317 Target supports constructors with initialization priority arguments.
2319 @item inttypes_types
2320 Target has the basic signed and unsigned types in @code{inttypes.h}.
2321 This is for tests that GCC's notions of these types agree with those
2322 in the header, as some systems have only @code{inttypes.h}.
2325 Target might have errors of a few ULP in string to floating-point
2326 conversion functions and overflow is not always detected correctly by
2330 Target provides @code{mempcpy} function.
2333 Target supports @code{mmap}.
2336 Target supports Newlib.
2338 @item newlib_nano_io
2339 GCC was configured with @code{--enable-newlib-nano-formatted-io}, which reduces
2340 the code size of Newlib formatted I/O functions.
2343 Target provides @code{pow10} function.
2346 Target can compile using @code{pthread.h} with no errors or warnings.
2349 Target has @code{pthread.h}.
2351 @item run_expensive_tests
2352 Expensive testcases (usually those that consume excessive amounts of CPU
2353 time) should be run on this target. This can be enabled by setting the
2354 @env{GCC_TEST_RUN_EXPENSIVE} environment variable to a non-empty string.
2357 Test system runs executables on a simulator (i.e.@: slowly) rather than
2358 hardware (i.e.@: fast).
2361 Target has @code{signal.h}.
2364 Target supports the stabs debugging format.
2367 Target has the basic signed and unsigned C types in @code{stdint.h}.
2368 This will be obsolete when GCC ensures a working @code{stdint.h} for
2372 Target provides @code{stpcpy} function.
2375 Target supports trampolines.
2378 Target supports uClibc.
2381 Target does not use a status wrapper.
2383 @item vxworks_kernel
2384 Target is a VxWorks kernel.
2387 Target is a VxWorks RTP.
2390 Target supports wide characters.
2393 @subsubsection Other attributes
2396 @item automatic_stack_alignment
2397 Target supports automatic stack alignment.
2400 Target supports @option{-branch-cost=N}.
2403 Target uses @code{__cxa_atexit}.
2405 @item default_packed
2406 Target has packed layout of structure members by default.
2409 Target supports exceptions.
2411 @item exceptions_enabled
2412 Target supports exceptions and they are enabled in the current
2413 testing configuration.
2416 Target supports Graphite optimizations.
2419 Target supports fixed-point extension to C.
2422 Target supports OpenACC via @option{-fopenacc}.
2425 Target supports OpenMP via @option{-fopenmp}.
2428 Target supports @option{-fpic} and @option{-fPIC}.
2431 Target supports @option{-freorder-blocks-and-partition}.
2433 @item fstack_protector
2434 Target supports @option{-fstack-protector}.
2437 Target uses GNU @command{as}.
2440 Target supports @option{--gc-sections}.
2443 Target uses GNU @command{ld}.
2445 @item keeps_null_pointer_checks
2446 Target keeps null pointer checks, either due to the use of
2447 @option{-fno-delete-null-pointer-checks} or hardwired into the target.
2450 Target is using an LLVM assembler and/or linker, instead of GNU Binutils.
2453 Compiler has been configured to support link-time optimization (LTO).
2455 @item lto_incremental
2456 Compiler and linker support link-time optimization relocatable linking
2457 with @option{-r} and @option{-flto} options.
2459 @item naked_functions
2460 Target supports the @code{naked} function attribute.
2462 @item named_sections
2463 Target supports named sections.
2465 @item natural_alignment_32
2466 Target uses natural alignment (aligned to type size) for types of
2469 @item target_natural_alignment_64
2470 Target uses natural alignment (aligned to type size) for types of
2474 Target supports the @code{noinit} variable attribute.
2477 Target does not generate PIC by default.
2480 Target has been configured for OpenACC/OpenMP offloading on AMD GCN.
2483 Target generates PIE by default.
2485 @item pcc_bitfield_type_matters
2486 Target defines @code{PCC_BITFIELD_TYPE_MATTERS}.
2488 @item pe_aligned_commons
2489 Target supports @option{-mpe-aligned-commons}.
2492 Target supports @option{-pie}, @option{-fpie} and @option{-fPIE}.
2495 Target supports @option{-rdynamic}.
2497 @item scalar_all_fma
2498 Target supports all four fused multiply-add optabs for both @code{float}
2499 and @code{double}. These optabs are: @code{fma_optab}, @code{fms_optab},
2500 @code{fnma_optab} and @code{fnms_optab}.
2502 @item section_anchors
2503 Target supports section anchors.
2506 Target defaults to short enums.
2509 @anchor{stack_size_et}
2510 Target has limited stack size. The stack size limit can be obtained using the
2511 STACK_SIZE macro defined by @ref{stack_size_ao,,@code{dg-add-options} feature
2515 Target supports @option{-static}.
2517 @item static_libgfortran
2518 Target supports statically linking @samp{libgfortran}.
2520 @item string_merging
2521 Target supports merging string constants at link time.
2524 Target supports compiling and assembling UCN.
2527 Including the options used to compile this particular test, the
2528 target supports compiling and assembling UCN.
2530 @item unaligned_stack
2531 Target does not guarantee that its @code{STACK_BOUNDARY} is greater than
2532 or equal to the required vector alignment.
2534 @item vector_alignment_reachable
2535 Vector alignment is reachable for types of 32 bits or less.
2537 @item vector_alignment_reachable_for_64bit
2538 Vector alignment is reachable for types of 64 bits or less.
2540 @item wchar_t_char16_t_compatible
2541 Target supports @code{wchar_t} that is compatible with @code{char16_t}.
2543 @item wchar_t_char32_t_compatible
2544 Target supports @code{wchar_t} that is compatible with @code{char32_t}.
2547 Target uses comdat groups.
2549 @item indirect_calls
2550 Target supports indirect calls, i.e. calls where the target is not
2554 Target supports -lgccjit, i.e. libgccjit.so can be linked into jit tests.
2557 @subsubsection Local to tests in @code{gcc.target/i386}
2561 Target supports compiling @code{3dnow} instructions.
2564 Target supports compiling @code{aes} instructions.
2567 Target supports compiling @code{fma4} instructions.
2570 Target supports the @code{-mfentry} option that alters the
2571 position of profiling calls such that they precede the prologue.
2573 @item ms_hook_prologue
2574 Target supports attribute @code{ms_hook_prologue}.
2577 Target supports compiling @code{pclmul} instructions.
2580 Target supports compiling @code{sse3} instructions.
2583 Target supports compiling @code{sse4} instructions.
2586 Target supports compiling @code{sse4a} instructions.
2589 Target supports compiling @code{ssse3} instructions.
2592 Target supports compiling @code{vaes} instructions.
2595 Target supports compiling @code{vpclmul} instructions.
2598 Target supports compiling @code{xop} instructions.
2601 @subsubsection Local to tests in @code{gcc.test-framework}
2612 @subsection Features for @code{dg-add-options}
2614 The supported values of @var{feature} for directive @code{dg-add-options}
2619 @code{__ARM_FP} definition. Only ARM targets support this feature, and only then
2620 in certain modes; see the @ref{arm_fp_ok,,arm_fp_ok effective target
2624 @code{__ARM_FP} definition with double-precision support. Only ARM
2625 targets support this feature, and only then in certain modes; see the
2626 @ref{arm_fp_dp_ok,,arm_fp_dp_ok effective target keyword}.
2629 NEON support. Only ARM targets support this feature, and only then
2630 in certain modes; see the @ref{arm_neon_ok,,arm_neon_ok effective target
2634 VFP half-precision floating point support. This does not select the
2635 FP16 format; for that, use @ref{arm_fp16_ieee,,arm_fp16_ieee} or
2636 @ref{arm_fp16_alternative,,arm_fp16_alternative} instead. This
2637 feature is only supported by ARM targets and then only in certain
2638 modes; see the @ref{arm_fp16_ok,,arm_fp16_ok effective target
2642 @anchor{arm_fp16_ieee}
2643 ARM IEEE 754-2008 format VFP half-precision floating point support.
2644 This feature is only supported by ARM targets and then only in certain
2645 modes; see the @ref{arm_fp16_ok,,arm_fp16_ok effective target
2648 @item arm_fp16_alternative
2649 @anchor{arm_fp16_alternative}
2650 ARM Alternative format VFP half-precision floating point support.
2651 This feature is only supported by ARM targets and then only in certain
2652 modes; see the @ref{arm_fp16_ok,,arm_fp16_ok effective target
2656 NEON and half-precision floating point support. Only ARM targets
2657 support this feature, and only then in certain modes; see
2658 the @ref{arm_neon_fp16_ok,,arm_neon_fp16_ok effective target keyword}.
2661 arm vfp3 floating point support; see
2662 the @ref{arm_vfp3_ok,,arm_vfp3_ok effective target keyword}.
2664 @item arm_arch_v8a_hard
2665 Add options for ARMv8-A and the hard-float variant of the AAPCS,
2666 if this is supported by the compiler; see the
2667 @ref{arm_arch_v8a_hard_ok,,arm_arch_v8a_hard_ok} effective target keyword.
2669 @item arm_v8_1a_neon
2670 Add options for ARMv8.1-A with Adv.SIMD support, if this is supported
2671 by the target; see the @ref{arm_v8_1a_neon_ok,,arm_v8_1a_neon_ok}
2672 effective target keyword.
2674 @item arm_v8_2a_fp16_scalar
2675 Add options for ARMv8.2-A with scalar FP16 support, if this is
2676 supported by the target; see the
2677 @ref{arm_v8_2a_fp16_scalar_ok,,arm_v8_2a_fp16_scalar_ok} effective
2680 @item arm_v8_2a_fp16_neon
2681 Add options for ARMv8.2-A with Adv.SIMD FP16 support, if this is
2682 supported by the target; see the
2683 @ref{arm_v8_2a_fp16_neon_ok,,arm_v8_2a_fp16_neon_ok} effective target
2686 @item arm_v8_2a_dotprod_neon
2687 Add options for ARMv8.2-A with Adv.SIMD Dot Product support, if this is
2688 supported by the target; see the
2689 @ref{arm_v8_2a_dotprod_neon_ok} effective target keyword.
2691 @item arm_fp16fml_neon
2692 Add options to enable generation of the @code{VFMAL} and @code{VFMSL}
2693 instructions, if this is supported by the target; see the
2694 @ref{arm_fp16fml_neon_ok} effective target keyword.
2696 @item bind_pic_locally
2697 Add the target-specific flags needed to enable functions to bind
2698 locally when using pic/PIC passes in the testsuite.
2701 Add the target-specific flags needed to use the @code{_Float@var{n}} type.
2704 Add the target-specific flags needed to use the @code{_Float@var{n}x} type.
2707 Add the target-specific flags needed to enable full IEEE
2710 @item mips16_attribute
2711 @code{mips16} function attributes.
2712 Only MIPS targets support this feature, and only then in certain modes.
2715 @anchor{stack_size_ao}
2716 Add the flags needed to define macro STACK_SIZE and set it to the stack size
2717 limit associated with the @ref{stack_size_et,,@code{stack_size} effective
2721 Add the target-specific flags needed to enable hardware square root
2722 instructions, if any.
2725 Add the target-specific flags needed to use thread-local storage.
2728 @node Require Support
2729 @subsection Variants of @code{dg-require-@var{support}}
2731 A few of the @code{dg-require} directives take arguments.
2734 @item dg-require-iconv @var{codeset}
2735 Skip the test if the target does not support iconv. @var{codeset} is
2736 the codeset to convert to.
2738 @item dg-require-profiling @var{profopt}
2739 Skip the test if the target does not support profiling with option
2742 @item dg-require-stack-check @var{check}
2743 Skip the test if the target does not support the @code{-fstack-check}
2744 option. If @var{check} is @code{""}, support for @code{-fstack-check}
2745 is checked, for @code{-fstack-check=("@var{check}")} otherwise.
2747 @item dg-require-stack-size @var{size}
2748 Skip the test if the target does not support a stack size of @var{size}.
2750 @item dg-require-visibility @var{vis}
2751 Skip the test if the target does not support the @code{visibility} attribute.
2752 If @var{vis} is @code{""}, support for @code{visibility("hidden")} is
2753 checked, for @code{visibility("@var{vis}")} otherwise.
2756 The original @code{dg-require} directives were defined before there
2757 was support for effective-target keywords. The directives that do not
2758 take arguments could be replaced with effective-target keywords.
2761 @item dg-require-alias ""
2762 Skip the test if the target does not support the @samp{alias} attribute.
2764 @item dg-require-ascii-locale ""
2765 Skip the test if the host does not support an ASCII locale.
2767 @item dg-require-compat-dfp ""
2768 Skip this test unless both compilers in a @file{compat} testsuite
2769 support decimal floating point.
2771 @item dg-require-cxa-atexit ""
2772 Skip the test if the target does not support @code{__cxa_atexit}.
2773 This is equivalent to @code{dg-require-effective-target cxa_atexit}.
2775 @item dg-require-dll ""
2776 Skip the test if the target does not support DLL attributes.
2778 @item dg-require-dot ""
2779 Skip the test if the host does not have @command{dot}.
2781 @item dg-require-fork ""
2782 Skip the test if the target does not support @code{fork}.
2784 @item dg-require-gc-sections ""
2785 Skip the test if the target's linker does not support the
2786 @code{--gc-sections} flags.
2787 This is equivalent to @code{dg-require-effective-target gc-sections}.
2789 @item dg-require-host-local ""
2790 Skip the test if the host is remote, rather than the same as the build
2791 system. Some tests are incompatible with DejaGnu's handling of remote
2792 hosts, which involves copying the source file to the host and compiling
2793 it with a relative path and "@code{-o a.out}".
2795 @item dg-require-mkfifo ""
2796 Skip the test if the target does not support @code{mkfifo}.
2798 @item dg-require-named-sections ""
2799 Skip the test is the target does not support named sections.
2800 This is equivalent to @code{dg-require-effective-target named_sections}.
2802 @item dg-require-weak ""
2803 Skip the test if the target does not support weak symbols.
2805 @item dg-require-weak-override ""
2806 Skip the test if the target does not support overriding weak symbols.
2810 @subsection Commands for use in @code{dg-final}
2812 The GCC testsuite defines the following directives to be used within
2815 @subsubsection Scan a particular file
2818 @item scan-file @var{filename} @var{regexp} [@{ target/xfail @var{selector} @}]
2819 Passes if @var{regexp} matches text in @var{filename}.
2820 @item scan-file-not @var{filename} @var{regexp} [@{ target/xfail @var{selector} @}]
2821 Passes if @var{regexp} does not match text in @var{filename}.
2822 @item scan-module @var{module} @var{regexp} [@{ target/xfail @var{selector} @}]
2823 Passes if @var{regexp} matches in Fortran module @var{module}.
2824 @item dg-check-dot @var{filename}
2825 Passes if @var{filename} is a valid @file{.dot} file (by running
2826 @code{dot -Tpng} on it, and verifying the exit code is 0).
2829 @subsubsection Scan the assembly output
2832 @item scan-assembler @var{regex} [@{ target/xfail @var{selector} @}]
2833 Passes if @var{regex} matches text in the test's assembler output.
2835 @item scan-assembler-not @var{regex} [@{ target/xfail @var{selector} @}]
2836 Passes if @var{regex} does not match text in the test's assembler output.
2838 @item scan-assembler-times @var{regex} @var{num} [@{ target/xfail @var{selector} @}]
2839 Passes if @var{regex} is matched exactly @var{num} times in the test's
2842 @item scan-assembler-dem @var{regex} [@{ target/xfail @var{selector} @}]
2843 Passes if @var{regex} matches text in the test's demangled assembler output.
2845 @item scan-assembler-dem-not @var{regex} [@{ target/xfail @var{selector} @}]
2846 Passes if @var{regex} does not match text in the test's demangled assembler
2849 @item scan-hidden @var{symbol} [@{ target/xfail @var{selector} @}]
2850 Passes if @var{symbol} is defined as a hidden symbol in the test's
2853 @item scan-not-hidden @var{symbol} [@{ target/xfail @var{selector} @}]
2854 Passes if @var{symbol} is not defined as a hidden symbol in the test's
2857 @item check-function-bodies @var{prefix} @var{terminator} [@var{options} [@{ target/xfail @var{selector} @}]]
2858 Looks through the source file for comments that give the expected assembly
2859 output for selected functions. Each line of expected output starts with the
2860 prefix string @var{prefix} and the expected output for a function as a whole
2861 is followed by a line that starts with the string @var{terminator}.
2862 Specifying an empty terminator is equivalent to specifying @samp{"*/"}.
2864 @var{options}, if specified, is a list of regular expressions, each of
2865 which matches a full command-line option. A non-empty list prevents
2866 the test from running unless all of the given options are present on the
2867 command line. This can help if a source file is compiled both with
2868 and without optimization, since it is rarely useful to check the full
2869 function body for unoptimized code.
2871 The first line of the expected output for a function @var{fn} has the form:
2874 @var{prefix} @var{fn}: [@{ target/xfail @var{selector} @}]
2877 Subsequent lines of the expected output also start with @var{prefix}.
2878 In both cases, whitespace after @var{prefix} is not significant.
2880 The test discards assembly directives such as @code{.cfi_startproc}
2881 and local label definitions such as @code{.LFB0} from the compiler's
2882 assembly output. It then matches the result against the expected
2883 output for a function as a single regular expression. This means that
2884 later lines can use backslashes to refer back to @samp{(@dots{})}
2885 captures on earlier lines. For example:
2888 /* @{ dg-final @{ check-function-bodies "**" "" "-DCHECK_ASM" @} @} */
2892 ** mov (z[0-9]+\.b), w0
2893 ** add z0\.b, p0/m, z0\.b, \1
2896 svint8_t add_w0_s8_m (@dots{}) @{ @dots{} @}
2900 ** mov (z[0-9]+\.b), b0
2901 ** add z1\.b, p0/m, z1\.b, \1
2904 svint8_t add_b0_s8_m (@dots{}) @{ @dots{} @}
2907 checks whether the implementations of @code{add_w0_s8_m} and
2908 @code{add_b0_s8_m} match the regular expressions given. The test only
2909 runs when @samp{-DCHECK_ASM} is passed on the command line.
2911 It is possible to create non-capturing multi-line regular expression
2912 groups of the form @samp{(@var{a}|@var{b}|@dots{})} by putting the
2913 @samp{(}, @samp{|} and @samp{)} on separate lines (each still using
2914 @var{prefix}). For example:
2920 ** fcmge p0\.h, p0/z, z1\.h, z0\.h
2922 ** fcmle p0\.h, p0/z, z0\.h, z1\.h
2926 svbool_t cmple_f16_tied (@dots{}) @{ @dots{} @}
2929 checks whether @code{cmple_f16_tied} is implemented by the
2930 @code{fcmge} instruction followed by @code{ret} or by the
2931 @code{fcmle} instruction followed by @code{ret}. The test is
2932 still a single regular rexpression.
2934 A line containing just:
2940 stands for zero or more unmatched lines; the whitespace after
2941 @var{prefix} is again not significant.
2945 @subsubsection Scan optimization dump files
2947 These commands are available for @var{kind} of @code{tree}, @code{ltrans-tree},
2948 @code{offload-tree}, @code{rtl}, @code{offload-rtl}, @code{ipa}, and
2952 @item scan-@var{kind}-dump @var{regex} @var{suffix} [@{ target/xfail @var{selector} @}]
2953 Passes if @var{regex} matches text in the dump file with suffix @var{suffix}.
2955 @item scan-@var{kind}-dump-not @var{regex} @var{suffix} [@{ target/xfail @var{selector} @}]
2956 Passes if @var{regex} does not match text in the dump file with suffix
2959 @item scan-@var{kind}-dump-times @var{regex} @var{num} @var{suffix} [@{ target/xfail @var{selector} @}]
2960 Passes if @var{regex} is found exactly @var{num} times in the dump file
2961 with suffix @var{suffix}.
2963 @item scan-@var{kind}-dump-dem @var{regex} @var{suffix} [@{ target/xfail @var{selector} @}]
2964 Passes if @var{regex} matches demangled text in the dump file with
2965 suffix @var{suffix}.
2967 @item scan-@var{kind}-dump-dem-not @var{regex} @var{suffix} [@{ target/xfail @var{selector} @}]
2968 Passes if @var{regex} does not match demangled text in the dump file with
2969 suffix @var{suffix}.
2972 The @var{suffix} argument which describes the dump file to be scanned
2973 may contain a glob pattern that must expand to exactly one file
2974 name. This is useful if, e.g., different pass instances are executed
2975 depending on torture testing command-line flags, producing dump files
2976 whose names differ only in their pass instance number suffix. For
2977 example, to scan instances 1, 2, 3 of a tree pass ``mypass'' for
2978 occurrences of the string ``code has been optimized'', use:
2980 /* @{ dg-options "-fdump-tree-mypass" @} */
2981 /* @{ dg-final @{ scan-tree-dump "code has been optimized" "mypass\[1-3\]" @} @} */
2985 @subsubsection Check for output files
2988 @item output-exists [@{ target/xfail @var{selector} @}]
2989 Passes if compiler output file exists.
2991 @item output-exists-not [@{ target/xfail @var{selector} @}]
2992 Passes if compiler output file does not exist.
2994 @item scan-symbol @var{regexp} [@{ target/xfail @var{selector} @}]
2995 Passes if the pattern is present in the final executable.
2997 @item scan-symbol-not @var{regexp} [@{ target/xfail @var{selector} @}]
2998 Passes if the pattern is absent from the final executable.
3001 @subsubsection Checks for @command{gcov} tests
3004 @item run-gcov @var{sourcefile}
3005 Check line counts in @command{gcov} tests.
3007 @item run-gcov [branches] [calls] @{ @var{opts} @var{sourcefile} @}
3008 Check branch and/or call counts, in addition to line counts, in
3009 @command{gcov} tests.
3012 @subsubsection Clean up generated test files
3014 Usually the test-framework removes files that were generated during
3015 testing. If a testcase, for example, uses any dumping mechanism to
3016 inspect a passes dump file, the testsuite recognized the dump option
3017 passed to the tool and schedules a final cleanup to remove these files.
3019 There are, however, following additional cleanup directives that can be
3020 used to annotate a testcase "manually".
3022 @item cleanup-coverage-files
3023 Removes coverage data files generated for this test.
3025 @item cleanup-modules "@var{list-of-extra-modules}"
3026 Removes Fortran module files generated for this test, excluding the
3027 module names listed in keep-modules.
3028 Cleaning up module files is usually done automatically by the testsuite
3029 by looking at the source files and removing the modules after the test
3040 ! @{ dg-final @{ cleanup-modules "mod1 mod2" @} @} ! redundant
3041 ! @{ dg-final @{ keep-modules "mod3 mod4" @} @}
3044 @item keep-modules "@var{list-of-modules-not-to-delete}"
3045 Whitespace separated list of module names that should not be deleted by
3047 If the list of modules is empty, all modules defined in this file are kept.
3049 module maybe_unneeded
3050 end module maybe_unneeded
3055 ! @{ dg-final @{ keep-modules "keep1 keep2" @} @} ! just keep these two
3056 ! @{ dg-final @{ keep-modules "" @} @} ! keep all
3059 @item dg-keep-saved-temps "@var{list-of-suffixes-not-to-delete}"
3060 Whitespace separated list of suffixes that should not be deleted
3061 automatically in a testcase that uses @option{-save-temps}.
3063 // @{ dg-options "-save-temps -fpch-preprocess -I." @}
3064 int main() @{ return 0; @}
3065 // @{ dg-keep-saved-temps ".s" @} ! just keep assembler file
3066 // @{ dg-keep-saved-temps ".s" ".i" @} ! ... and .i
3067 // @{ dg-keep-saved-temps ".ii" ".o" @} ! or just .ii and .o
3070 @item cleanup-profile-file
3071 Removes profiling files generated for this test.
3076 @section Ada Language Testsuites
3078 The Ada testsuite includes executable tests from the ACATS
3079 testsuite, publicly available at
3080 @uref{http://www.ada-auth.org/acats.html}.
3082 These tests are integrated in the GCC testsuite in the
3083 @file{ada/acats} directory, and
3084 enabled automatically when running @code{make check}, assuming
3085 the Ada language has been enabled when configuring GCC@.
3087 You can also run the Ada testsuite independently, using
3088 @code{make check-ada}, or run a subset of the tests by specifying which
3089 chapter to run, e.g.:
3092 $ make check-ada CHAPTERS="c3 c9"
3095 The tests are organized by directory, each directory corresponding to
3096 a chapter of the Ada Reference Manual. So for example, @file{c9} corresponds
3097 to chapter 9, which deals with tasking features of the language.
3099 The tests are run using two @command{sh} scripts: @file{run_acats} and
3100 @file{run_all.sh}. To run the tests using a simulator or a cross
3101 target, see the small
3102 customization section at the top of @file{run_all.sh}.
3104 These tests are run using the build tree: they can be run without doing
3105 a @code{make install}.
3108 @section C Language Testsuites
3110 GCC contains the following C language testsuites, in the
3111 @file{gcc/testsuite} directory:
3115 This contains tests of particular features of the C compiler, using the
3116 more modern @samp{dg} harness. Correctness tests for various compiler
3117 features should go here if possible.
3119 Magic comments determine whether the file
3120 is preprocessed, compiled, linked or run. In these tests, error and warning
3121 message texts are compared against expected texts or regular expressions
3122 given in comments. These tests are run with the options @samp{-ansi -pedantic}
3123 unless other options are given in the test. Except as noted below they
3124 are not run with multiple optimization options.
3126 This subdirectory contains tests for binary compatibility using
3127 @file{lib/compat.exp}, which in turn uses the language-independent support
3128 (@pxref{compat Testing, , Support for testing binary compatibility}).
3130 This subdirectory contains tests of the preprocessor.
3132 This subdirectory contains tests for debug formats. Tests in this
3133 subdirectory are run for each debug format that the compiler supports.
3135 This subdirectory contains tests of the @option{-Wformat} format
3136 checking. Tests in this directory are run with and without
3138 @item gcc.dg/noncompile
3139 This subdirectory contains tests of code that should not compile and
3140 does not need any special compilation options. They are run with
3141 multiple optimization options, since sometimes invalid code crashes
3142 the compiler with optimization.
3143 @item gcc.dg/special
3144 FIXME: describe this.
3147 This contains particular code fragments which have historically broken easily.
3148 These tests are run with multiple optimization options, so tests for features
3149 which only break at some optimization levels belong here. This also contains
3150 tests to check that certain optimizations occur. It might be worthwhile to
3151 separate the correctness tests cleanly from the code quality tests, but
3152 it hasn't been done yet.
3154 @item gcc.c-torture/compat
3155 FIXME: describe this.
3157 This directory should probably not be used for new tests.
3158 @item gcc.c-torture/compile
3159 This testsuite contains test cases that should compile, but do not
3160 need to link or run. These test cases are compiled with several
3161 different combinations of optimization options. All warnings are
3162 disabled for these test cases, so this directory is not suitable if
3163 you wish to test for the presence or absence of compiler warnings.
3164 While special options can be set, and tests disabled on specific
3165 platforms, by the use of @file{.x} files, mostly these test cases
3166 should not contain platform dependencies. FIXME: discuss how defines
3167 such as @code{STACK_SIZE} are used.
3168 @item gcc.c-torture/execute
3169 This testsuite contains test cases that should compile, link and run;
3170 otherwise the same comments as for @file{gcc.c-torture/compile} apply.
3171 @item gcc.c-torture/execute/ieee
3172 This contains tests which are specific to IEEE floating point.
3173 @item gcc.c-torture/unsorted
3174 FIXME: describe this.
3176 This directory should probably not be used for new tests.
3177 @item gcc.misc-tests
3178 This directory contains C tests that require special handling. Some
3179 of these tests have individual expect files, and others share
3180 special-purpose expect files:
3183 @item @code{bprob*.c}
3184 Test @option{-fbranch-probabilities} using
3185 @file{gcc.misc-tests/bprob.exp}, which
3186 in turn uses the generic, language-independent framework
3187 (@pxref{profopt Testing, , Support for testing profile-directed
3190 @item @code{gcov*.c}
3191 Test @command{gcov} output using @file{gcov.exp}, which in turn uses the
3192 language-independent support (@pxref{gcov Testing, , Support for testing gcov}).
3194 @item @code{i386-pf-*.c}
3195 Test i386-specific support for data prefetch using @file{i386-prefetch.exp}.
3198 @item gcc.test-framework
3201 Test the testsuite itself using @file{gcc.test-framework/test-framework.exp}.
3206 FIXME: merge in @file{testsuite/README.gcc} and discuss the format of
3207 test cases and magic comments more.
3210 @section Support for testing link-time optimizations
3212 Tests for link-time optimizations usually require multiple source files
3213 that are compiled separately, perhaps with different sets of options.
3214 There are several special-purpose test directives used for these tests.
3217 @item @{ dg-lto-do @var{do-what-keyword} @}
3218 @var{do-what-keyword} specifies how the test is compiled and whether
3219 it is executed. It is one of:
3223 Compile with @option{-c} to produce a relocatable object file.
3225 Compile, assemble, and link to produce an executable file.
3227 Produce and run an executable file, which is expected to return
3231 The default is @code{assemble}. That can be overridden for a set of
3232 tests by redefining @code{dg-do-what-default} within the @code{.exp}
3233 file for those tests.
3235 Unlike @code{dg-do}, @code{dg-lto-do} does not support an optional
3236 @samp{target} or @samp{xfail} list. Use @code{dg-skip-if},
3237 @code{dg-xfail-if}, or @code{dg-xfail-run-if}.
3239 @item @{ dg-lto-options @{ @{ @var{options} @} [@{ @var{options} @}] @} [@{ target @var{selector} @}]@}
3240 This directive provides a list of one or more sets of compiler options
3241 to override @var{LTO_OPTIONS}. Each test will be compiled and run with
3242 each of these sets of options.
3244 @item @{ dg-extra-ld-options @var{options} [@{ target @var{selector} @}]@}
3245 This directive adds @var{options} to the linker options used.
3247 @item @{ dg-suppress-ld-options @var{options} [@{ target @var{selector} @}]@}
3248 This directive removes @var{options} from the set of linker options used.
3252 @section Support for testing @command{gcov}
3254 Language-independent support for testing @command{gcov}, and for checking
3255 that branch profiling produces expected values, is provided by the
3256 expect file @file{lib/gcov.exp}. @command{gcov} tests also rely on procedures
3257 in @file{lib/gcc-dg.exp} to compile and run the test program. A typical
3258 @command{gcov} test contains the following DejaGnu commands within comments:
3261 @{ dg-options "--coverage" @}
3262 @{ dg-do run @{ target native @} @}
3263 @{ dg-final @{ run-gcov sourcefile @} @}
3266 Checks of @command{gcov} output can include line counts, branch percentages,
3267 and call return percentages. All of these checks are requested via
3268 commands that appear in comments in the test's source file.
3269 Commands to check line counts are processed by default.
3270 Commands to check branch percentages and call return percentages are
3271 processed if the @command{run-gcov} command has arguments @code{branches}
3272 or @code{calls}, respectively. For example, the following specifies
3273 checking both, as well as passing @option{-b} to @command{gcov}:
3276 @{ dg-final @{ run-gcov branches calls @{ -b sourcefile @} @} @}
3279 A line count command appears within a comment on the source line
3280 that is expected to get the specified count and has the form
3281 @code{count(@var{cnt})}. A test should only check line counts for
3282 lines that will get the same count for any architecture.
3284 Commands to check branch percentages (@code{branch}) and call
3285 return percentages (@code{returns}) are very similar to each other.
3286 A beginning command appears on or before the first of a range of
3287 lines that will report the percentage, and the ending command
3288 follows that range of lines. The beginning command can include a
3289 list of percentages, all of which are expected to be found within
3290 the range. A range is terminated by the next command of the same
3291 kind. A command @code{branch(end)} or @code{returns(end)} marks
3292 the end of a range without starting a new one. For example:
3295 if (i > 10 && j > i && j < 20) /* @r{branch(27 50 75)} */
3296 /* @r{branch(end)} */
3300 For a call return percentage, the value specified is the
3301 percentage of calls reported to return. For a branch percentage,
3302 the value is either the expected percentage or 100 minus that
3303 value, since the direction of a branch can differ depending on the
3304 target or the optimization level.
3306 Not all branches and calls need to be checked. A test should not
3307 check for branches that might be optimized away or replaced with
3308 predicated instructions. Don't check for calls inserted by the
3309 compiler or ones that might be inlined or optimized away.
3311 A single test can check for combinations of line counts, branch
3312 percentages, and call return percentages. The command to check a
3313 line count must appear on the line that will report that count, but
3314 commands to check branch percentages and call return percentages can
3315 bracket the lines that report them.
3317 @node profopt Testing
3318 @section Support for testing profile-directed optimizations
3320 The file @file{profopt.exp} provides language-independent support for
3321 checking correct execution of a test built with profile-directed
3322 optimization. This testing requires that a test program be built and
3323 executed twice. The first time it is compiled to generate profile
3324 data, and the second time it is compiled to use the data that was
3325 generated during the first execution. The second execution is to
3326 verify that the test produces the expected results.
3328 To check that the optimization actually generated better code, a
3329 test can be built and run a third time with normal optimizations to
3330 verify that the performance is better with the profile-directed
3331 optimizations. @file{profopt.exp} has the beginnings of this kind
3334 @file{profopt.exp} provides generic support for profile-directed
3335 optimizations. Each set of tests that uses it provides information
3336 about a specific optimization:
3340 tool being tested, e.g., @command{gcc}
3342 @item profile_option
3343 options used to generate profile data
3345 @item feedback_option
3346 options used to optimize using that profile data
3349 suffix of profile data files
3351 @item PROFOPT_OPTIONS
3352 list of options with which to run each test, similar to the lists for
3355 @item @{ dg-final-generate @{ @var{local-directive} @} @}
3356 This directive is similar to @code{dg-final}, but the
3357 @var{local-directive} is run after the generation of profile data.
3359 @item @{ dg-final-use @{ @var{local-directive} @} @}
3360 The @var{local-directive} is run after the profile data have been
3364 @node compat Testing
3365 @section Support for testing binary compatibility
3367 The file @file{compat.exp} provides language-independent support for
3368 binary compatibility testing. It supports testing interoperability of
3369 two compilers that follow the same ABI, or of multiple sets of
3370 compiler options that should not affect binary compatibility. It is
3371 intended to be used for testsuites that complement ABI testsuites.
3373 A test supported by this framework has three parts, each in a
3374 separate source file: a main program and two pieces that interact
3375 with each other to split up the functionality being tested.
3378 @item @var{testname}_main.@var{suffix}
3379 Contains the main program, which calls a function in file
3380 @file{@var{testname}_x.@var{suffix}}.
3382 @item @var{testname}_x.@var{suffix}
3383 Contains at least one call to a function in
3384 @file{@var{testname}_y.@var{suffix}}.
3386 @item @var{testname}_y.@var{suffix}
3387 Shares data with, or gets arguments from,
3388 @file{@var{testname}_x.@var{suffix}}.
3391 Within each test, the main program and one functional piece are
3392 compiled by the GCC under test. The other piece can be compiled by
3393 an alternate compiler. If no alternate compiler is specified,
3394 then all three source files are all compiled by the GCC under test.
3395 You can specify pairs of sets of compiler options. The first element
3396 of such a pair specifies options used with the GCC under test, and the
3397 second element of the pair specifies options used with the alternate
3398 compiler. Each test is compiled with each pair of options.
3400 @file{compat.exp} defines default pairs of compiler options.
3401 These can be overridden by defining the environment variable
3402 @env{COMPAT_OPTIONS} as:
3405 COMPAT_OPTIONS="[list [list @{@var{tst1}@} @{@var{alt1}@}]
3406 @dots{}[list @{@var{tstn}@} @{@var{altn}@}]]"
3409 where @var{tsti} and @var{alti} are lists of options, with @var{tsti}
3410 used by the compiler under test and @var{alti} used by the alternate
3411 compiler. For example, with
3412 @code{[list [list @{-g -O0@} @{-O3@}] [list @{-fpic@} @{-fPIC -O2@}]]},
3413 the test is first built with @option{-g -O0} by the compiler under
3414 test and with @option{-O3} by the alternate compiler. The test is
3415 built a second time using @option{-fpic} by the compiler under test
3416 and @option{-fPIC -O2} by the alternate compiler.
3418 An alternate compiler is specified by defining an environment
3419 variable to be the full pathname of an installed compiler; for C
3420 define @env{ALT_CC_UNDER_TEST}, and for C++ define
3421 @env{ALT_CXX_UNDER_TEST}. These will be written to the
3422 @file{site.exp} file used by DejaGnu. The default is to build each
3423 test with the compiler under test using the first of each pair of
3424 compiler options from @env{COMPAT_OPTIONS}. When
3425 @env{ALT_CC_UNDER_TEST} or
3426 @env{ALT_CXX_UNDER_TEST} is @code{same}, each test is built using
3427 the compiler under test but with combinations of the options from
3428 @env{COMPAT_OPTIONS}.
3430 To run only the C++ compatibility suite using the compiler under test
3431 and another version of GCC using specific compiler options, do the
3432 following from @file{@var{objdir}/gcc}:
3437 ALT_CXX_UNDER_TEST=$@{alt_prefix@}/bin/g++ \
3438 COMPAT_OPTIONS="@var{lists as shown above}" \
3440 RUNTESTFLAGS="compat.exp"
3443 A test that fails when the source files are compiled with different
3444 compilers, but passes when the files are compiled with the same
3445 compiler, demonstrates incompatibility of the generated code or
3446 runtime support. A test that fails for the alternate compiler but
3447 passes for the compiler under test probably tests for a bug that was
3448 fixed in the compiler under test but is present in the alternate
3451 The binary compatibility tests support a small number of test framework
3452 commands that appear within comments in a test file.
3456 These commands can be used in @file{@var{testname}_main.@var{suffix}}
3457 to skip the test if specific support is not available on the target.
3460 The specified options are used for compiling this particular source
3461 file, appended to the options from @env{COMPAT_OPTIONS}. When this
3462 command appears in @file{@var{testname}_main.@var{suffix}} the options
3463 are also used to link the test program.
3466 This command can be used in a secondary source file to specify that
3467 compilation is expected to fail for particular options on particular
3472 @section Support for torture testing using multiple options
3474 Throughout the compiler testsuite there are several directories whose
3475 tests are run multiple times, each with a different set of options.
3476 These are known as torture tests.
3477 @file{lib/torture-options.exp} defines procedures to
3482 Initialize use of torture lists.
3483 @item set-torture-options
3484 Set lists of torture options to use for tests with and without loops.
3485 Optionally combine a set of torture options with a set of other
3486 options, as is done with Objective-C runtime options.
3487 @item torture-finish
3488 Finalize use of torture lists.
3491 The @file{.exp} file for a set of tests that use torture options must
3492 include calls to these three procedures if:
3495 @item It calls @code{gcc-dg-runtest} and overrides @var{DG_TORTURE_OPTIONS}.
3497 @item It calls @var{$@{tool@}}@code{-torture} or
3498 @var{$@{tool@}}@code{-torture-execute}, where @var{tool} is @code{c},
3499 @code{fortran}, or @code{objc}.
3501 @item It calls @code{dg-pch}.
3504 It is not necessary for a @file{.exp} file that calls @code{gcc-dg-runtest}
3505 to call the torture procedures if the tests should use the list in
3506 @var{DG_TORTURE_OPTIONS} defined in @file{gcc-dg.exp}.
3508 Most uses of torture options can override the default lists by defining
3509 @var{TORTURE_OPTIONS} or add to the default list by defining
3510 @var{ADDITIONAL_TORTURE_OPTIONS}. Define these in a @file{.dejagnurc}
3511 file or add them to the @file{site.exp} file; for example
3514 set ADDITIONAL_TORTURE_OPTIONS [list \
3515 @{ -O2 -ftree-loop-linear @} \
3516 @{ -O2 -fpeel-loops @} ]
3520 @section Support for testing GIMPLE passes
3522 As of gcc 7, C functions can be tagged with @code{__GIMPLE} to indicate
3523 that the function body will be GIMPLE, rather than C. The compiler requires
3524 the option @option{-fgimple} to enable this functionality. For example:
3527 /* @{ dg-do compile @} */
3528 /* @{ dg-options "-O -fgimple" @} */
3530 void __GIMPLE (startwith ("dse2")) foo ()
3548 a_1 = __PHI (bb_3: a_2, bb_4: a_3);
3555 The @code{startwith} argument indicates at which pass to begin.
3557 Use the dump modifier @code{-gimple} (e.g.@: @option{-fdump-tree-all-gimple})
3558 to make tree dumps more closely follow the format accepted by the GIMPLE
3561 Example DejaGnu tests of GIMPLE can be seen in the source tree at
3562 @file{gcc/testsuite/gcc.dg/gimplefe-*.c}.
3564 The @code{__GIMPLE} parser is integrated with the C tokenizer and
3565 preprocessor, so it should be possible to use macros to build out
3569 @section Support for testing RTL passes
3571 As of gcc 7, C functions can be tagged with @code{__RTL} to indicate that the
3572 function body will be RTL, rather than C. For example:
3575 double __RTL (startwith ("ira")) test (struct foo *f, const struct bar *b)
3578 [...snip; various directives go in here...]
3579 ) ;; function "test"
3583 The @code{startwith} argument indicates at which pass to begin.
3585 The parser expects the RTL body to be in the format emitted by this
3590 print_rtx_function (FILE *outfile, function *fn, bool compact);
3593 when "compact" is true. So you can capture RTL in the correct format
3594 from the debugger using:
3597 (gdb) print_rtx_function (stderr, cfun, true);
3600 and copy and paste the output into the body of the C function.
3602 Example DejaGnu tests of RTL can be seen in the source tree under
3603 @file{gcc/testsuite/gcc.dg/rtl}.
3605 The @code{__RTL} parser is not integrated with the C tokenizer or
3606 preprocessor, and works simply by reading the relevant lines within
3607 the braces. In particular, the RTL body must be on separate lines from
3608 the enclosing braces, and the preprocessor is not usable within it.