-@c Copyright (C) 2002 Free Software Foundation, Inc.
+@c Copyright (C) 2002, 2003, 2004, 2005, 2007, 2008 Free Software Foundation,
+@c Inc.
@c This is part of the GCC manual.
@c For copying conditions, see the file gcc.texi.
* Configure Terms:: Configuration terminology and history.
* Top Level:: The top level source directory.
* gcc Directory:: The @file{gcc} subdirectory.
-* Test Suites:: The GCC test suites.
+* Testsuites:: The GCC testsuites.
@end menu
@include configterms.texi
@item gcc
The main sources of GCC itself (except for runtime libraries),
including optimizers, support for different target architectures,
-language front ends, and test suites. @xref{gcc Directory, , The
+language front ends, and testsuites. @xref{gcc Directory, , The
@file{gcc} Subdirectory}, for details.
@item include
Headers for the @code{libiberty} library.
-@item libf2c
+@item libada
+The Ada runtime library.
+
+@item libcpp
+The C preprocessor library.
+
+@item libgfortran
The Fortran runtime library.
@item libffi
@item libjava
The Java runtime library.
+@item libmudflap
+The @code{libmudflap} library, used for instrumenting pointer and array
+dereferencing operations.
+
@item libobjc
-The Objective-C runtime library.
+The Objective-C and Objective-C++ runtime library.
@item libstdc++-v3
The C++ runtime library.
The @file{gcc} directory contains many files that are part of the C
sources of GCC, other files used as part of the configuration and
build process, and subdirectories including documentation and a
-test suite. The files that are sources of GCC are documented in a
+testsuite. The files that are sources of GCC are documented in a
separate chapter. @xref{Passes, , Passes and Files of the Compiler}.
@menu
@item @var{language}
Subdirectories for various languages. Directories containing a file
@file{config-lang.in} are language subdirectories. The contents of
-the subdirectories @file{cp} (for C++) and @file{objc} (for
-Objective-C) are documented in this manual (@pxref{Passes, , Passes
-and Files of the Compiler}); those for other languages are not.
-@xref{Front End, , Anatomy of a Language Front End}, for details of
-the files in these directories.
+the subdirectories @file{cp} (for C++), @file{objc} (for Objective-C)
+and @file{objcp} (for Objective-C++) are documented in this manual
+(@pxref{Passes, , Passes and Files of the Compiler}); those for other
+languages are not. @xref{Front End, , Anatomy of a Language Front End},
+for details of the files in these directories.
@item config
Configuration files for supported architectures and operating
systems. @xref{Back End, , Anatomy of a Target Back End}, for
-details of the files in thie directory.
+details of the files in this directory.
@item doc
Texinfo documentation for GCC, together with automatically generated
contains @file{gcc.pot}, the template for these message catalogues,
@file{exgettext}, a wrapper around @command{gettext} to extract the
messages from the GCC sources and create @file{gcc.pot}, which is run
-by @command{make gcc.pot}, and @file{EXCLUDES}, a list of files from
+by @samp{make gcc.pot}, and @file{EXCLUDES}, a list of files from
which messages should not be extracted.
@item testsuite
-The GCC test suites (except for those for runtime libraries).
-@xref{Test Suites}.
+The GCC testsuites (except for those for runtime libraries).
+@xref{Testsuites}.
@end table
@node Configuration
The @file{gcc} directory is configured with an Autoconf-generated
script @file{configure}. The @file{configure} script is generated
-from @file{configure.in} and @file{aclocal.m4}. From the files
-@file{configure.in} and @file{acconfig.h}, Autoheader generates the
+from @file{configure.ac} and @file{aclocal.m4}. From the files
+@file{configure.ac} and @file{acconfig.h}, Autoheader generates the
file @file{config.in}. The file @file{cstamp-h.in} is used as a
timestamp.
@menu
* Config Fragments:: Scripts used by @file{configure}.
-* System Config:: The @file{config.gcc} file.
+* System Config:: The @file{config.build}, @file{config.host}, and
+ @file{config.gcc} files.
* Configuration Files:: Files created by running @file{configure}.
@end menu
the top level one) used?
@item The file @file{config.gcc} is used to handle configuration
-specific to the particular build, host or target machine. (In
-general, this should only be used for features that cannot reasonably
-be tested in Autoconf feature tests.) @xref{System Config, , The
-@file{config.gcc} File}, for details of the contents of this file.
+specific to the particular target machine. The file
+@file{config.build} is used to handle configuration specific to the
+particular build machine. The file @file{config.host} is used to handle
+configuration specific to the particular host machine. (In general,
+these should only be used for features that cannot reasonably be tested in
+Autoconf feature tests.)
+@xref{System Config, , The @file{config.build}; @file{config.host};
+and @file{config.gcc} Files}, for details of the contents of these files.
@item Each language subdirectory has a file
@file{@var{language}/config-lang.in} that is used for
@end itemize
@node System Config
-@subsubsection The @file{config.gcc} File
+@subsubsection The @file{config.build}; @file{config.host}; and @file{config.gcc} Files
+
+The @file{config.build} file contains specific rules for particular systems
+which GCC is built on. This should be used as rarely as possible, as the
+behavior of the build system can always be detected by autoconf.
+
+The @file{config.host} file contains specific rules for particular systems
+which GCC will run on. This is rarely needed.
+
+The @file{config.gcc} file contains specific rules for particular systems
+which GCC will generate code for. This is usually needed.
-FIXME: document the contents of this file, and what variables should
+Each file has a list of the shell variables it sets, with descriptions, at the
+top of the file.
+
+FIXME: document the contents of these files, and what variables should
be set to control build, host and target configuration.
@include configfiles.texi
Several of the headers GCC installs are in the @file{ginclude}
directory. These headers, @file{iso646.h},
-@file{stdarg.h}, @file{stdbool.h}, @file{stddef.h} and
-@file{varargs.h}, are installed in @file{@var{libsubdir}/include},
+@file{stdarg.h}, @file{stdbool.h}, and @file{stddef.h},
+are installed in @file{@var{libsubdir}/include},
unless the target Makefile fragment (@pxref{Target Fragment})
overrides this by setting @code{USER_H}.
headers to work with GCC, some other headers may also be installed in
@file{@var{libsubdir}/include}. @file{config.gcc} may set
@code{extra_headers}; this specifies additional headers under
-@file{config} to be installed on some systems. GCC normally installs
-a @code{<float.h>} file; these are kept as
-@file{config/float-@var{format}.h}, where @var{format} is specified by
-a @code{float_format} setting in @file{config.gcc}, and a setting
-@samp{float_format=none} disables installation of this header. GCC
-also installs its own version of @code{<limits.h>}; this is generated
+@file{config} to be installed on some systems.
+
+GCC installs its own version of @code{<float.h>}, from @file{ginclude/float.h}.
+This is done to cope with command-line options that change the
+representation of floating point numbers.
+
+GCC also installs its own version of @code{<limits.h>}; this is generated
from @file{glimits.h}, together with @file{limitx.h} and
@file{limity.h} if the system also has its own version of
@code{<limits.h>}. (GCC provides its own header because it is
@file{gsyslimits.h} if it does not need fixing to work with GCC; if it
needs fixing, @file{syslimits.h} is the fixed copy.
+GCC can also install @code{<tgmath.h>}. It will do this when
+@file{config.gcc} sets @code{use_gcc_tgmath} to @code{yes}.
+
@node Documentation
@subsection Building Documentation
The main GCC documentation is in the form of manuals in Texinfo
-format. These are installed in Info format, and DVI versions may be
-generated by @command{make dvi}. In addition, some man pages are
+format. These are installed in Info format; DVI versions may be
+generated by @samp{make dvi}, PDF versions by @samp{make pdf}, and
+HTML versions by @command{make html}. In addition, some man pages are
generated from the Texinfo manuals, there are some other text files
with miscellaneous documentation, and runtime libraries have their own
documentation outside the @file{gcc} directory. FIXME: document the
@item gcc-common.texi
Common definitions for manuals.
@item gpl.texi
+@itemx gpl_v3.texi
The GNU General Public License.
@item texinfo.tex
A copy of @file{texinfo.tex} known to work with the GCC manuals.
@end table
-DVI formatted manuals are generated by @command{make dvi}, which uses
-@command{texi2dvi} (via the Makefile macro @code{$(TEXI2DVI)}). Info
-manuals are generated by @command{make info} (which is run as part of
+DVI-formatted manuals are generated by @samp{make dvi}, which uses
+@command{texi2dvi} (via the Makefile macro @code{$(TEXI2DVI)}).
+PDF-formatted manuals are generated by @samp{make pdf}, which uses
+@command{texi2pdf} (via the Makefile macro @code{$(TEXI2PDF)}). HTML
+formatted manuals are generated by @command{make html}. Info
+manuals are generated by @samp{make info} (which is run as part of
a bootstrap); this generates the manuals in the source directory,
using @command{makeinfo} via the Makefile macro @code{$(MAKEINFO)},
and they are included in release distributions.
more than once in the source tree.) The manual file
@file{@var{name}.texi} should only include other files in its own
directory or in @file{doc/include}. HTML manuals will be generated by
-@command{makeinfo --html} and PostScript manuals by @command{texi2dvi}
-and @command{dvips}. All Texinfo files that are parts of manuals must
-be checked into CVS, even if they are generated files, for the
+@samp{makeinfo --html}, PostScript manuals by @command{texi2dvi}
+and @command{dvips}, and PDF manuals by @command{texi2pdf}.
+All Texinfo files that are parts of manuals must
+be checked into SVN, even if they are generated files, for the
generation of online manuals to work.
The installation manual, @file{doc/install.texi}, is also provided on
@item README.Portability
Information about portability issues when writing code in GCC@. FIXME:
why isn't this part of this manual or of the GCC Coding Conventions?
-@item SERVICE
-A pointer to the GNU Service Directory.
@end table
FIXME: document such files in subdirectories, at least @file{config},
A mention of the language in the list of supported languages in
@file{gcc/doc/install.texi}.
@item
+A mention of the name under which the language's runtime library is
+recognized by @option{--enable-shared=@var{package}} in the
+documentation of that option in @file{gcc/doc/install.texi}.
+@item
+A mention of any special prerequisites for building the front end in
+the documentation of prerequisites in @file{gcc/doc/install.texi}.
+@item
Details of contributors to that front end in
@file{gcc/doc/contrib.texi}. If the details are in that front end's
own manual then there should be a link to that manual's list in
Entries in @code{default_compilers} in @file{gcc.c} for source file
suffixes for that language.
@item
-Preferably test suites, which may be under @file{gcc/testsuite} or
+Preferably testsuites, which may be under @file{gcc/testsuite} or
runtime library directories. FIXME: document somewhere how to write
-test suite harnesses.
+testsuite harnesses.
@item
Probably a runtime library for the language, outside the @file{gcc}
directory. FIXME: document this further.
@file{gcc/doc/sourcebuild.texi}.
@end itemize
-If the front end is added to the official GCC CVS repository, the
+If the front end is added to the official GCC source repository, the
following are also necessary:
@itemize @bullet
@item
-At least one GNATS category for bugs in that front end and runtime
+At least one Bugzilla component for bugs in that front end and runtime
libraries. This category needs to be mentioned in
-@file{gcc/gccbug.in}, and in @file{gnats.html} on the GCC web site, as
-well as being added to the GNATS database.
+@file{gcc/gccbug.in}, as well as being added to the Bugzilla database.
@item
Normally, one or more maintainers of that front end listed in
@file{MAINTAINERS}.
If this front end includes its own version files that include the
current date, @file{maintainer-scripts/update_version} should be
updated accordingly.
-@item
-@file{CVSROOT/modules} in the GCC CVS repository should be updated.
@end itemize
@menu
values of @code{@var{hook}}, and any other Makefile rules required to
build those targets (which may if necessary use other Makefiles
specified in @code{outputs} in @file{config-lang.in}, although this is
-deprecated).
+deprecated). It also adds any testsuite targets that can use the
+standard rule in @file{gcc/Makefile.in} to the variable
+@code{lang_checks}.
@table @code
-@item all.build
@itemx all.cross
@itemx start.encap
@itemx rest.encap
FIXME: exactly what goes in each of these targets?
+@item tags
+Build an @command{etags} @file{TAGS} file in the language subdirectory
+in the source tree.
@item info
-Build info documentation for the front end, in the source directory.
-This target is only called by @command{make bootstrap} if a suitable
+Build info documentation for the front end, in the build directory.
+This target is only called by @samp{make bootstrap} if a suitable
version of @command{makeinfo} is available, so does not need to check
for this, and should fail if an error occurs.
@item dvi
Build DVI documentation for the front end, in the build directory.
This should be done using @code{$(TEXI2DVI)}, with appropriate
@option{-I} arguments pointing to directories of included files.
-@item generated-manpages
+@item pdf
+Build PDF documentation for the front end, in the build directory.
+This should be done using @code{$(TEXI2PDF)}, with appropriate
+@option{-I} arguments pointing to directories of included files.
+@item html
+Build HTML documentation for the front end, in the build directory.
+@item man
Build generated man pages for the front end from Texinfo manuals
-(@pxref{Man Page Generation}), in the source directory. This target
+(@pxref{Man Page Generation}), in the build directory. This target
is only called if the necessary tools are available, but should ignore
errors so as not to stop the build if errors occur; man pages are
optional and the tools involved may be installed in a broken way.
-@item install-normal
-FIXME: what is this target for?
@item install-common
Install everything that is part of the front end, apart from the
compiler executables listed in @code{compilers} in
-@file{config-lang.in} that are installed in @file{@var{libsubdir}} by
-the main @file{Makefile}.
+@file{config-lang.in}.
@item install-info
Install info documentation for the front end, if it is present in the
-source directory. (It may not be present if a suitable version of
-@command{makeinfo} was not installed.) This target should run the
-command @command{install-info} to update the info directory, but
-should ignore errors when running that command.
+source directory. This target should have dependencies on info files
+that should be installed.
@item install-man
Install man pages for the front end. This target should ignore
errors.
+@item srcextra
+Copies its dependencies into the source directory. This generally should
+be used for generated files such as Bison output files which are not
+present in CVS, but should be included in any release tarballs. This
+target will be executed during a bootstrap if
+@samp{--enable-generated-files-in-srcdir} was specified as a
+@file{configure} option.
+@item srcinfo
+@itemx srcman
+Copies its dependencies into the source directory. These targets will be
+executed during a bootstrap if @samp{--enable-generated-files-in-srcdir}
+was specified as a @file{configure} option.
@item uninstall
Uninstall files installed by installing the compiler. This is
currently documented not to be supported, so the hook need not do
@item mostlyclean
@itemx clean
@itemx distclean
-@itemx extraclean
@itemx maintainer-clean
-Except for @code{extraclean}, the language parts of the standard GNU
-@samp{*clean} targets. @xref{Standard Targets, , Standard Targets for
+The language parts of the standard GNU
+@samp{*clean} targets. @xref{Standard Targets, , Standard Targets for
Users, standards, GNU Coding Standards}, for details of the standard
-targets. @code{extraclean} does @code{distclean} and also deletes
-anything likely to be found in the source directory that shouldn't be
-in the distribution. For GCC, @code{maintainer-clean} should delete
+targets. For GCC, @code{maintainer-clean} should delete
all generated files in the source directory that are not checked into
CVS, but should not delete anything checked into CVS@.
-@item stage1
-@itemx stage2
-@itemx stage3
-@itemx stage4
-Move to the stage directory files not included in @code{stagestuff} in
-@file{config-lang.in} or otherwise moved by the main @file{Makefile}.
@end table
-@item lang-options.h
-This file provides entries for @code{documented_lang_options} in
-@file{toplev.c} describing command-line options the front end accepts
-for @option{--help} output.
+@item lang.opt
+This file registers the set of switches that the front end accepts on
+the command line, and their @option{--help} text. @xref{Options}.
@item lang-specs.h
This file provides entries for @code{default_compilers} in
@file{gcc.c} which override the default of giving an error that a
@node Front End Config
@subsubsection The Front End @file{config-lang.in} File
-Each language subdirectory contains a @file{config-lang.in} file.
-This file is a shell script that may define some variables describing
-the language:
+Each language subdirectory contains a @file{config-lang.in} file. In
+addition the main directory contains @file{c-config-lang.in}, which
+contains limited information for the C language. This file is a shell
+script that may define some variables describing the language:
@table @code
@item language
names given being their @code{language} settings). For example, the
Java front end depends on the C++ front end, so sets
@samp{lang_requires=c++}.
+@item subdir_requires
+If defined, this variable lists (space-separated) front end directories
+other than C that this front end requires to be present. For example,
+the Objective-C++ front end uses source files from the C++ and
+Objective-C front ends, so sets @samp{subdir_requires="cp objc"}.
@item target_libs
If defined, this variable lists (space-separated) targets in the top
level @file{Makefile} to build the runtime libraries for this
If defined to @samp{no}, this language front end is not built unless
enabled in a @option{--enable-languages} argument. Otherwise, front
ends are built by default, subject to any special logic in
-@file{configure.in} (as is present to disable the Ada front end if the
+@file{configure.ac} (as is present to disable the Ada front end if the
Ada compiler is not already installed).
@item boot_language
If defined to @samp{yes}, this front end is built in stage 1 of the
bootstrap. This is only relevant to front ends written in their own
languages.
@item compilers
-If defined, a space-separated list of compiler executables that should
-be installed in @file{@var{libsubdir}}. The names here will each end
+If defined, a space-separated list of compiler executables that will
+be run by the driver. The names here will each end
with @samp{\$(exeext)}.
-@item stagestuff
-If defined, a space-separated list of files that should be moved to
-the @file{stage@var{n}} directories in each stage of bootstrap.
@item outputs
If defined, a space-separated list of files that should be generated
by @file{configure} substituting values in them. This mechanism can
be used to create a file @file{@var{language}/Makefile} from
@file{@var{language}/Makefile.in}, but this is deprecated, building
everything from the single @file{gcc/Makefile} is preferred.
+@item gtfiles
+If defined, a space-separated list of files that should be scanned by
+gengtype.c to generate the garbage collection tables and routines for
+this language. This excludes the files that are common to all front
+ends. @xref{Type Information}.
+
@end table
@node Back End
@file{@var{machine}} directory, containing additional machine modes to
represent condition codes. @xref{Condition Code}, for further details.
@item
+An optional @file{@var{machine}.opt} file in the @file{@var{machine}}
+directory, containing a list of target-specific options. You can also
+add other option files using the @code{extra_options} variable in
+@file{config.gcc}. @xref{Options}.
+@item
Entries in @file{config.gcc} (@pxref{System Config, , The
@file{config.gcc} File}) for the systems with this target
architecture.
Documentation in @file{gcc/doc/extend.texi} of any target-specific
built-in functions supported.
@item
+Documentation in @file{gcc/doc/extend.texi} of any target-specific
+format checking styles supported.
+@item
Documentation in @file{gcc/doc/md.texi} of any target-specific
constraint letters (@pxref{Machine Constraints, , Constraints for
Particular Machines}).
chapter of this manual.
@end itemize
-If the back end is added to the official GCC CVS repository, the
+If the back end is added to the official GCC source repository, the
following are also necessary:
@itemize @bullet
An entry for the target architecture in @file{readings.html} on the
GCC web site, with any relevant links.
@item
+Details of the properties of the back end and target architecture in
+@file{backends.html} on the GCC web site.
+@item
A news item about the contribution of support for that target
architecture, in @file{index.html} on the GCC web site.
@item
a maintainer when support is added.
@end itemize
-@node Test Suites
-@section Test Suites
+@node Testsuites
+@section Testsuites
-GCC contains several test suites to help maintain compiler quality.
-Most of the runtime libraries and language front ends in GCC have test
-suites. Currently only the C language test suites are documented
+GCC contains several testsuites to help maintain compiler quality.
+Most of the runtime libraries and language front ends in GCC have
+testsuites. Currently only the C language testsuites are documented
here; FIXME: document the others.
@menu
-* Test Idioms:: Idioms used in test suite code.
-* C Tests:: The C language test suites.
+* Test Idioms:: Idioms used in testsuite code.
+* Test Directives:: Directives used within DejaGnu tests.
+* Ada Tests:: The Ada language testsuites.
+* C Tests:: The C language testsuites.
+* libgcj Tests:: The Java library testsuites.
+* gcov Testing:: Support for testing gcov.
+* profopt Testing:: Support for testing profile-directed optimizations.
+* compat Testing:: Support for testing binary compatibility.
@end menu
@node Test Idioms
-@subsection Idioms Used in Test Suite Code
-
-In the @file{gcc.c-torture} test suites, test cases are commonly named
-after the date on which they were added. This allows people to tell
-at a glance whether a test failure is because of a recently found bug
-that has not yet been fixed, or whether it may be a regression. In
-other test suites, more descriptive names are used. In general C test
-cases have a trailing @file{-@var{n}.c}, starting with @file{-1.c}, in
-case other test cases with similar names are added later.
-
-Test cases should use @code{abort ()} to indicate failure and
-@code{exit (0)} for success; on some targets these may be redefined to
-indicate failure and success in other ways.
-
-In the @file{gcc.dg} test suite, it is often necessary to test that an
+@subsection Idioms Used in Testsuite Code
+
+In general, C testcases have a trailing @file{-@var{n}.c}, starting
+with @file{-1.c}, in case other testcases with similar names are added
+later. If the test is a test of some well-defined feature, it should
+have a name referring to that feature such as
+@file{@var{feature}-1.c}. If it does not test a well-defined feature
+but just happens to exercise a bug somewhere in the compiler, and a
+bug report has been filed for this bug in the GCC bug database,
+@file{pr@var{bug-number}-1.c} is the appropriate form of name.
+Otherwise (for miscellaneous bugs not filed in the GCC bug database),
+and previously more generally, test cases are named after the date on
+which they were added. This allows people to tell at a glance whether
+a test failure is because of a recently found bug that has not yet
+been fixed, or whether it may be a regression, but does not give any
+other information about the bug or where discussion of it may be
+found. Some other language testsuites follow similar conventions.
+
+In the @file{gcc.dg} testsuite, it is often necessary to test that an
error is indeed a hard error and not just a warning---for example,
where it is a constraint violation in the C standard, which must
become an error with @option{-pedantic-errors}. The following idiom,
@code{static} to call @code{abort ()} (although redeclaring a function
as static may not work on all targets).
-FIXME: discuss non-C test suites here.
+All testcases must be portable. Target-specific testcases must have
+appropriate code to avoid causing failures on unsupported systems;
+unfortunately, the mechanisms for this differ by directory.
+
+FIXME: discuss non-C testsuites here.
+
+@node Test Directives
+@subsection Directives used within DejaGnu tests
+
+Test directives appear within comments in a test source file and begin
+with @code{dg-}. Some of these are defined within DejaGnu and others
+are local to the GCC testsuite.
+
+The order in which test directives appear in a test can be important:
+directives local to GCC sometimes override information used by the
+DejaGnu directives, which know nothing about the GCC directives, so the
+DejaGnu directives must precede GCC directives.
+
+Several test directives include selectors which are usually preceded by
+the keyword @code{target} or @code{xfail}. A selector is: one or more
+target triplets, possibly including wildcard characters; a single
+effective-target keyword; or a logical expression. Depending on the
+context, the selector specifies whether a test is skipped and reported
+as unsupported or is expected to fail. Use @samp{*-*-*} to match any
+target.
+Effective-target keywords are defined in @file{target-supports.exp} in
+the GCC testsuite.
+
+A selector expression appears within curly braces and uses a single
+logical operator: one of @samp{!}, @samp{&&}, or @samp{||}. An
+operand is another selector expression, an effective-target keyword,
+a single target triplet, or a list of target triplets within quotes or
+curly braces. For example:
+
+@smallexample
+@{ target @{ ! "hppa*-*-* ia64*-*-*" @} @}
+@{ target @{ powerpc*-*-* && lp64 @} @}
+@{ xfail @{ lp64 || vect_no_align @} @}
+@end smallexample
+
+@table @code
+@item @{ dg-do @var{do-what-keyword} [@{ target/xfail @var{selector} @}] @}
+@var{do-what-keyword} specifies how the test is compiled and whether
+it is executed. It is one of:
+
+@table @code
+@item preprocess
+Compile with @option{-E} to run only the preprocessor.
+@item compile
+Compile with @option{-S} to produce an assembly code file.
+@item assemble
+Compile with @option{-c} to produce a relocatable object file.
+@item link
+Compile, assemble, and link to produce an executable file.
+@item run
+Produce and run an executable file, which is expected to return
+an exit code of 0.
+@end table
+
+The default is @code{compile}. That can be overridden for a set of
+tests by redefining @code{dg-do-what-default} within the @code{.exp}
+file for those tests.
+
+If the directive includes the optional @samp{@{ target @var{selector} @}}
+then the test is skipped unless the target system is included in the
+list of target triplets or matches the effective-target keyword.
+
+If @samp{do-what-keyword} is @code{run} and the directive includes
+the optional @samp{@{ xfail @var{selector} @}} and the selector is met
+then the test is expected to fail. The @code{xfail} clause is ignored
+for other values of @samp{do-what-keyword}; those tests can use
+directive @code{dg-xfail-if}.
+
+@item @{ dg-options @var{options} [@{ target @var{selector} @}] @}
+This DejaGnu directive provides a list of compiler options, to be used
+if the target system matches @var{selector}, that replace the default
+options used for this set of tests.
+
+@item @{ dg-add-options @var{feature} @dots{} @}
+Add any compiler options that are needed to access certain features.
+This directive does nothing on targets that enable the features by
+default, or that don't provide them at all. It must come after
+all @code{dg-options} directives.
+
+The supported values of @var{feature} are:
+@table @code
+@item c99_runtime
+The target's C99 runtime (both headers and libraries).
+
+@item mips16_attribute
+@code{mips16} function attributes. Only MIPS targets support this feature,
+and only then in certain modes.
+@end table
+
+@item @{ dg-skip-if @var{comment} @{ @var{selector} @} @{ @var{include-opts} @} @{ @var{exclude-opts} @} @}
+Skip the test if the test system is included in @var{selector} and if
+each of the options in @var{include-opts} is in the set of options with
+which the test would be compiled and if none of the options in
+@var{exclude-opts} is in the set of options with which the test would be
+compiled.
+
+Use @samp{"*"} for an empty @var{include-opts} list and @samp{""} for
+an empty @var{exclude-opts} list.
+
+@item @{ dg-xfail-if @var{comment} @{ @var{selector} @} @{ @var{include-opts} @} @{ @var{exclude-opts} @} @}
+Expect the test to fail if the conditions (which are the same as for
+@code{dg-skip-if}) are met.
+
+@item @{ dg-require-@var{support} args @}
+Skip the test if the target does not provide the required support;
+see @file{gcc-dg.exp} in the GCC testsuite for the actual directives.
+These directives must appear after any @code{dg-do} directive in the test
+and before any @code{dg-additional-sources} directive.
+They require at least one argument, which can be an empty string if the
+specific procedure does not examine the argument.
+
+@item @{ dg-require-effective-target @var{keyword} @}
+Skip the test if the test target, including current multilib flags,
+is not covered by the effective-target keyword.
+This directive must appear after any @code{dg-do} directive in the test
+and before any @code{dg-additional-sources} directive.
+
+@item @{ dg-shouldfail @var{comment} @{ @var{selector} @} @{ @var{include-opts} @} @{ @var{exclude-opts} @} @}
+Expect the test executable to return a nonzero exit status if the
+conditions (which are the same as for @code{dg-skip-if}) are met.
+
+@item @{ dg-error @var{regexp} [@var{comment} [@{ target/xfail @var{selector} @} [@var{line}] @}]] @}
+This DejaGnu directive appears on a source line that is expected to get
+an error message, or else specifies the source line associated with the
+message. If there is no message for that line or if the text of that
+message is not matched by @var{regexp} then the check fails and
+@var{comment} is included in the @code{FAIL} message. The check does
+not look for the string @samp{"error"} unless it is part of @var{regexp}.
+
+@item @{ dg-warning @var{regexp} [@var{comment} [@{ target/xfail @var{selector} @} [@var{line}] @}]] @}
+This DejaGnu directive appears on a source line that is expected to get
+a warning message, or else specifies the source line associated with the
+message. If there is no message for that line or if the text of that
+message is not matched by @var{regexp} then the check fails and
+@var{comment} is included in the @code{FAIL} message. The check does
+not look for the string @samp{"warning"} unless it is part of @var{regexp}.
+
+@item @{ dg-message @var{regexp} [@var{comment} [@{ target/xfail @var{selector} @} [@var{line}] @}]] @}
+The line is expected to get a message other than an error or warning.
+If there is no message for that line or if the text of that message is
+not matched by @var{regexp} then the check fails and @var{comment} is
+included in the @code{FAIL} message.
+
+@item @{ dg-bogus @var{regexp} [@var{comment} [@{ target/xfail @var{selector} @} [@var{line}] @}]] @}
+This DejaGnu directive appears on a source line that should not get a
+message matching @var{regexp}, or else specifies the source line
+associated with the bogus message. It is usually used with @samp{xfail}
+to indicate that the message is a known problem for a particular set of
+targets.
+
+@item @{ dg-excess-errors @var{comment} [@{ target/xfail @var{selector} @}] @}
+This DejaGnu directive indicates that the test is expected to fail due
+to compiler messages that are not handled by @samp{dg-error},
+@samp{dg-warning} or @samp{dg-bogus}. For this directive @samp{xfail}
+has the same effect as @samp{target}.
+
+@item @{ dg-output @var{regexp} [@{ target/xfail @var{selector} @}] @}
+This DejaGnu directive compares @var{regexp} to the combined output
+that the test executable writes to @file{stdout} and @file{stderr}.
+
+@item @{ dg-prune-output @var{regexp} @}
+Prune messages matching @var{regexp} from test output.
+
+@item @{ dg-additional-files "@var{filelist}" @}
+Specify additional files, other than source files, that must be copied
+to the system where the compiler runs.
+
+@item @{ dg-additional-sources "@var{filelist}" @}
+Specify additional source files to appear in the compile line
+following the main test file.
+
+@item @{ dg-final @{ @var{local-directive} @} @}
+This DejaGnu directive is placed within a comment anywhere in the
+source file and is processed after the test has been compiled and run.
+Multiple @samp{dg-final} commands are processed in the order in which
+they appear in the source file.
+
+The GCC testsuite defines the following directives to be used within
+@code{dg-final}.
+
+@table @code
+@item cleanup-coverage-files
+Removes coverage data files generated for this test.
+
+@item cleanup-repo-files
+Removes files generated for this test for @option{-frepo}.
+
+@item cleanup-rtl-dump @var{suffix}
+Removes RTL dump files generated for this test.
+
+@item cleanup-tree-dump @var{suffix}
+Removes tree dump files matching @var{suffix} which were generated for
+this test.
+
+@item cleanup-saved-temps
+Removes files for the current test which were kept for @option{--save-temps}.
+
+@item scan-file @var{filename} @var{regexp} [@{ target/xfail @var{selector} @}]
+Passes if @var{regexp} matches text in @var{filename}.
+
+@item scan-file-not @var{filename} @var{regexp} [@{ target/xfail @var{selector} @}]
+Passes if @var{regexp} does not match text in @var{filename}.
+
+@item scan-hidden @var{symbol} [@{ target/xfail @var{selector} @}]
+Passes if @var{symbol} is defined as a hidden symbol in the test's
+assembly output.
+
+@item scan-not-hidden @var{symbol} [@{ target/xfail @var{selector} @}]
+Passes if @var{symbol} is not defined as a hidden symbol in the test's
+assembly output.
+
+@item scan-assembler-times @var{regex} @var{num} [@{ target/xfail @var{selector} @}]
+Passes if @var{regex} is matched exactly @var{num} times in the test's
+assembler output.
+
+@item scan-assembler @var{regex} [@{ target/xfail @var{selector} @}]
+Passes if @var{regex} matches text in the test's assembler output.
+
+@item scan-assembler-not @var{regex} [@{ target/xfail @var{selector} @}]
+Passes if @var{regex} does not match text in the test's assembler output.
+
+@item scan-assembler-dem @var{regex} [@{ target/xfail @var{selector} @}]
+Passes if @var{regex} matches text in the test's demangled assembler output.
+
+@item scan-assembler-dem-not @var{regex} [@{ target/xfail @var{selector} @}]
+Passes if @var{regex} does not match text in the test's demangled assembler
+output.
+
+@item scan-tree-dump-times @var{regex} @var{num} @var{suffix} [@{ target/xfail @var{selector} @}]
+Passes if @var{regex} is found exactly @var{num} times in the dump file
+with suffix @var{suffix}.
+
+@item scan-tree-dump @var{regex} @var{suffix} [@{ target/xfail @var{selector} @}]
+Passes if @var{regex} matches text in the dump file with suffix @var{suffix}.
+
+@item scan-tree-dump-not @var{regex} @var{suffix} [@{ target/xfail @var{selector} @}]
+Passes if @var{regex} does not match text in the dump file with suffix
+@var{suffix}.
+
+@item scan-tree-dump-dem @var{regex} @var{suffix} [@{ target/xfail @var{selector} @}]
+Passes if @var{regex} matches demangled text in the dump file with
+suffix @var{suffix}.
+
+@item scan-tree-dump-dem-not @var{regex} @var{suffix} [@{ target/xfail @var{selector} @}]
+Passes if @var{regex} does not match demangled text in the dump file with
+suffix @var{suffix}.
+
+@item output-exists [@{ target/xfail @var{selector} @}]
+Passes if compiler output file exists.
+
+@item output-exists-not [@{ target/xfail @var{selector} @}]
+Passes if compiler output file does not exist.
+
+@item run-gcov @var{sourcefile}
+Check line counts in @command{gcov} tests.
+
+@item run-gcov [branches] [calls] @{ @var{opts} @var{sourcefile} @}
+Check branch and/or call counts, in addition to line counts, in
+@command{gcov} tests.
+@end table
+@end table
+
+@node Ada Tests
+@subsection Ada Language Testsuites
+
+The Ada testsuite includes executable tests from the ACATS 2.5
+testsuite, publicly available at
+@uref{http://www.adaic.org/compilers/acats/2.5}
+
+These tests are integrated in the GCC testsuite in the
+@file{gcc/testsuite/ada/acats} directory, and
+enabled automatically when running @code{make check}, assuming
+the Ada language has been enabled when configuring GCC@.
+
+You can also run the Ada testsuite independently, using
+@code{make check-ada}, or run a subset of the tests by specifying which
+chapter to run, e.g.:
+
+@smallexample
+$ make check-ada CHAPTERS="c3 c9"
+@end smallexample
+
+The tests are organized by directory, each directory corresponding to
+a chapter of the Ada Reference Manual. So for example, c9 corresponds
+to chapter 9, which deals with tasking features of the language.
+
+There is also an extra chapter called @file{gcc} containing a template for
+creating new executable tests.
+
+The tests are run using two @command{sh} scripts: @file{run_acats} and
+@file{run_all.sh}. To run the tests using a simulator or a cross
+target, see the small
+customization section at the top of @file{run_all.sh}.
+
+These tests are run using the build tree: they can be run without doing
+a @code{make install}.
@node C Tests
-@subsection C Language Test Suites
+@subsection C Language Testsuites
-GCC contains the following C language test suites, in the
+GCC contains the following C language testsuites, in the
@file{gcc/testsuite} directory:
@table @file
-@item gcc.c-torture/compat
-FIXME: describe this.
-
-This directory should probably not be used for new tests.
-@item gcc.c-torture/compile
-This test suite contains test cases that should compile, but do not
-need to link or run. These test cases are compiled with several
-different combinations of optimization options. All warnings are
-disabled for these test cases, so this directory is not suitable if
-you wish to test for the presence or absence of compiler warnings.
-While special options can be set, and tests disabled on specific
-platforms, by the use of @file{.x} files, mostly these test cases
-should not contain platform dependencies. FIXME: discuss how defines
-such as @code{NO_LABEL_VALUES} and @code{STACK_SIZE} are used.
-@item gcc.c-torture/execute
-This test suite contains test cases that should compile, link and run;
-otherwise the same comments as for @file{gcc.c-torture/compile} apply.
-@item gcc.c-torture/unsorted
-FIXME: describe this.
-
-This directory should probably not be used for new tests.
@item gcc.dg
-This test suite contains tests using the more modern @samp{dg} harness.
-Magic comments determine whether the file is preprocessed, compiled,
-linked or run. In these tests, error and warning message texts are
-compared against expected texts or regular expressions given in
-comments. These tests are run with the options @samp{-ansi -pedantic}
+This contains tests of particular features of the C compiler, using the
+more modern @samp{dg} harness. Correctness tests for various compiler
+features should go here if possible.
+
+Magic comments determine whether the file
+is preprocessed, compiled, linked or run. In these tests, error and warning
+message texts are compared against expected texts or regular expressions
+given in comments. These tests are run with the options @samp{-ansi -pedantic}
unless other options are given in the test. Except as noted below they
are not run with multiple optimization options.
+@item gcc.dg/compat
+This subdirectory contains tests for binary compatibility using
+@file{compat.exp}, which in turn uses the language-independent support
+(@pxref{compat Testing, , Support for testing binary compatibility}).
@item gcc.dg/cpp
This subdirectory contains tests of the preprocessor.
@item gcc.dg/debug
the compiler with optimization.
@item gcc.dg/special
FIXME: describe this.
+
+@item gcc.c-torture
+This contains particular code fragments which have historically broken easily.
+These tests are run with multiple optimization options, so tests for features
+which only break at some optimization levels belong here. This also contains
+tests to check that certain optimizations occur. It might be worthwhile to
+separate the correctness tests cleanly from the code quality tests, but
+it hasn't been done yet.
+
+@item gcc.c-torture/compat
+FIXME: describe this.
+
+This directory should probably not be used for new tests.
+@item gcc.c-torture/compile
+This testsuite contains test cases that should compile, but do not
+need to link or run. These test cases are compiled with several
+different combinations of optimization options. All warnings are
+disabled for these test cases, so this directory is not suitable if
+you wish to test for the presence or absence of compiler warnings.
+While special options can be set, and tests disabled on specific
+platforms, by the use of @file{.x} files, mostly these test cases
+should not contain platform dependencies. FIXME: discuss how defines
+such as @code{NO_LABEL_VALUES} and @code{STACK_SIZE} are used.
+@item gcc.c-torture/execute
+This testsuite contains test cases that should compile, link and run;
+otherwise the same comments as for @file{gcc.c-torture/compile} apply.
+@item gcc.c-torture/execute/ieee
+This contains tests which are specific to IEEE floating point.
+@item gcc.c-torture/unsorted
+FIXME: describe this.
+
+This directory should probably not be used for new tests.
@item gcc.c-torture/misc-tests
-FIXME: describe this, when it should be used for new tests and when it
-shouldn't.
+This directory contains C tests that require special handling. Some
+of these tests have individual expect files, and others share
+special-purpose expect files:
+
+@table @file
+@item @code{bprob*.c}
+Test @option{-fbranch-probabilities} using @file{bprob.exp}, which
+in turn uses the generic, language-independent framework
+(@pxref{profopt Testing, , Support for testing profile-directed
+optimizations}).
+
+@item @code{dg-*.c}
+Test the testsuite itself using @file{dg-test.exp}.
+
+@item @code{gcov*.c}
+Test @command{gcov} output using @file{gcov.exp}, which in turn uses the
+language-independent support (@pxref{gcov Testing, , Support for testing gcov}).
+
+@item @code{i386-pf-*.c}
+Test i386-specific support for data prefetch using @file{i386-prefetch.exp}.
+@end table
+
@end table
FIXME: merge in @file{testsuite/README.gcc} and discuss the format of
test cases and magic comments more.
+
+@node libgcj Tests
+@subsection The Java library testsuites.
+
+Runtime tests are executed via @samp{make check} in the
+@file{@var{target}/libjava/testsuite} directory in the build
+tree. Additional runtime tests can be checked into this testsuite.
+
+Regression testing of the core packages in libgcj is also covered by the
+Mauve testsuite. The @uref{http://sourceware.org/mauve/,,Mauve Project}
+develops tests for the Java Class Libraries. These tests are run as part
+of libgcj testing by placing the Mauve tree within the libjava testsuite
+sources at @file{libjava/testsuite/libjava.mauve/mauve}, or by specifying
+the location of that tree when invoking @samp{make}, as in
+@samp{make MAUVEDIR=~/mauve check}.
+
+To detect regressions, a mechanism in @file{mauve.exp} compares the
+failures for a test run against the list of expected failures in
+@file{libjava/testsuite/libjava.mauve/xfails} from the source hierarchy.
+Update this file when adding new failing tests to Mauve, or when fixing
+bugs in libgcj that had caused Mauve test failures.
+
+We encourage developers to contribute test cases to Mauve.
+
+@node gcov Testing
+@subsection Support for testing @command{gcov}
+
+Language-independent support for testing @command{gcov}, and for checking
+that branch profiling produces expected values, is provided by the
+expect file @file{gcov.exp}. @command{gcov} tests also rely on procedures
+in @file{gcc.dg.exp} to compile and run the test program. A typical
+@command{gcov} test contains the following DejaGnu commands within comments:
+
+@smallexample
+@{ dg-options "-fprofile-arcs -ftest-coverage" @}
+@{ dg-do run @{ target native @} @}
+@{ dg-final @{ run-gcov sourcefile @} @}
+@end smallexample
+
+Checks of @command{gcov} output can include line counts, branch percentages,
+and call return percentages. All of these checks are requested via
+commands that appear in comments in the test's source file.
+Commands to check line counts are processed by default.
+Commands to check branch percentages and call return percentages are
+processed if the @command{run-gcov} command has arguments @code{branches}
+or @code{calls}, respectively. For example, the following specifies
+checking both, as well as passing @option{-b} to @command{gcov}:
+
+@smallexample
+@{ dg-final @{ run-gcov branches calls @{ -b sourcefile @} @} @}
+@end smallexample
+
+A line count command appears within a comment on the source line
+that is expected to get the specified count and has the form
+@code{count(@var{cnt})}. A test should only check line counts for
+lines that will get the same count for any architecture.
+
+Commands to check branch percentages (@code{branch}) and call
+return percentages (@code{returns}) are very similar to each other.
+A beginning command appears on or before the first of a range of
+lines that will report the percentage, and the ending command
+follows that range of lines. The beginning command can include a
+list of percentages, all of which are expected to be found within
+the range. A range is terminated by the next command of the same
+kind. A command @code{branch(end)} or @code{returns(end)} marks
+the end of a range without starting a new one. For example:
+
+@smallexample
+if (i > 10 && j > i && j < 20) /* @r{branch(27 50 75)} */
+ /* @r{branch(end)} */
+ foo (i, j);
+@end smallexample
+
+For a call return percentage, the value specified is the
+percentage of calls reported to return. For a branch percentage,
+the value is either the expected percentage or 100 minus that
+value, since the direction of a branch can differ depending on the
+target or the optimization level.
+
+Not all branches and calls need to be checked. A test should not
+check for branches that might be optimized away or replaced with
+predicated instructions. Don't check for calls inserted by the
+compiler or ones that might be inlined or optimized away.
+
+A single test can check for combinations of line counts, branch
+percentages, and call return percentages. The command to check a
+line count must appear on the line that will report that count, but
+commands to check branch percentages and call return percentages can
+bracket the lines that report them.
+
+@node profopt Testing
+@subsection Support for testing profile-directed optimizations
+
+The file @file{profopt.exp} provides language-independent support for
+checking correct execution of a test built with profile-directed
+optimization. This testing requires that a test program be built and
+executed twice. The first time it is compiled to generate profile
+data, and the second time it is compiled to use the data that was
+generated during the first execution. The second execution is to
+verify that the test produces the expected results.
+
+To check that the optimization actually generated better code, a
+test can be built and run a third time with normal optimizations to
+verify that the performance is better with the profile-directed
+optimizations. @file{profopt.exp} has the beginnings of this kind
+of support.
+
+@file{profopt.exp} provides generic support for profile-directed
+optimizations. Each set of tests that uses it provides information
+about a specific optimization:
+
+@table @code
+@item tool
+tool being tested, e.g., @command{gcc}
+
+@item profile_option
+options used to generate profile data
+
+@item feedback_option
+options used to optimize using that profile data
+
+@item prof_ext
+suffix of profile data files
+
+@item PROFOPT_OPTIONS
+list of options with which to run each test, similar to the lists for
+torture tests
+@end table
+
+@node compat Testing
+@subsection Support for testing binary compatibility
+
+The file @file{compat.exp} provides language-independent support for
+binary compatibility testing. It supports testing interoperability of
+two compilers that follow the same ABI, or of multiple sets of
+compiler options that should not affect binary compatibility. It is
+intended to be used for testsuites that complement ABI testsuites.
+
+A test supported by this framework has three parts, each in a
+separate source file: a main program and two pieces that interact
+with each other to split up the functionality being tested.
+
+@table @file
+@item @var{testname}_main.@var{suffix}
+Contains the main program, which calls a function in file
+@file{@var{testname}_x.@var{suffix}}.
+
+@item @var{testname}_x.@var{suffix}
+Contains at least one call to a function in
+@file{@var{testname}_y.@var{suffix}}.
+
+@item @var{testname}_y.@var{suffix}
+Shares data with, or gets arguments from,
+@file{@var{testname}_x.@var{suffix}}.
+@end table
+
+Within each test, the main program and one functional piece are
+compiled by the GCC under test. The other piece can be compiled by
+an alternate compiler. If no alternate compiler is specified,
+then all three source files are all compiled by the GCC under test.
+You can specify pairs of sets of compiler options. The first element
+of such a pair specifies options used with the GCC under test, and the
+second element of the pair specifies options used with the alternate
+compiler. Each test is compiled with each pair of options.
+
+@file{compat.exp} defines default pairs of compiler options.
+These can be overridden by defining the environment variable
+@env{COMPAT_OPTIONS} as:
+
+@smallexample
+COMPAT_OPTIONS="[list [list @{@var{tst1}@} @{@var{alt1}@}]
+ @dots{}[list @{@var{tstn}@} @{@var{altn}@}]]"
+@end smallexample
+
+where @var{tsti} and @var{alti} are lists of options, with @var{tsti}
+used by the compiler under test and @var{alti} used by the alternate
+compiler. For example, with
+@code{[list [list @{-g -O0@} @{-O3@}] [list @{-fpic@} @{-fPIC -O2@}]]},
+the test is first built with @option{-g -O0} by the compiler under
+test and with @option{-O3} by the alternate compiler. The test is
+built a second time using @option{-fpic} by the compiler under test
+and @option{-fPIC -O2} by the alternate compiler.
+
+An alternate compiler is specified by defining an environment
+variable to be the full pathname of an installed compiler; for C
+define @env{ALT_CC_UNDER_TEST}, and for C++ define
+@env{ALT_CXX_UNDER_TEST}. These will be written to the
+@file{site.exp} file used by DejaGnu. The default is to build each
+test with the compiler under test using the first of each pair of
+compiler options from @env{COMPAT_OPTIONS}. When
+@env{ALT_CC_UNDER_TEST} or
+@env{ALT_CXX_UNDER_TEST} is @code{same}, each test is built using
+the compiler under test but with combinations of the options from
+@env{COMPAT_OPTIONS}.
+
+To run only the C++ compatibility suite using the compiler under test
+and another version of GCC using specific compiler options, do the
+following from @file{@var{objdir}/gcc}:
+
+@smallexample
+rm site.exp
+make -k \
+ ALT_CXX_UNDER_TEST=$@{alt_prefix@}/bin/g++ \
+ COMPAT_OPTIONS="lists as shown above" \
+ check-c++ \
+ RUNTESTFLAGS="compat.exp"
+@end smallexample
+
+A test that fails when the source files are compiled with different
+compilers, but passes when the files are compiled with the same
+compiler, demonstrates incompatibility of the generated code or
+runtime support. A test that fails for the alternate compiler but
+passes for the compiler under test probably tests for a bug that was
+fixed in the compiler under test but is present in the alternate
+compiler.
+
+The binary compatibility tests support a small number of test framework
+commands that appear within comments in a test file.
+
+@table @code
+@item dg-require-*
+These commands can be used in @file{@var{testname}_main.@var{suffix}}
+to skip the test if specific support is not available on the target.
+
+@item dg-options
+The specified options are used for compiling this particular source
+file, appended to the options from @env{COMPAT_OPTIONS}. When this
+command appears in @file{@var{testname}_main.@var{suffix}} the options
+are also used to link the test program.
+
+@item dg-xfail-if
+This command can be used in a secondary source file to specify that
+compilation is expected to fail for particular options on particular
+targets.
+@end table