+The libstdc++ testsuite includes testing for standard conformance, +regressions, ABI, and performance. +
+ The directory libsrcdir/testsuite contains the + individual test cases organized in sub-directories corresponding to + chapters of the C++ standard (detailed below), the dejagnu test + harness support files, and sources to various testsuite utilities + that are packaged in a separate testing library. +
+ All test cases for functionality required by the runtime components + of the C++ standard (ISO 14882) are files within the following + directories. +
+17_intro +18_support +19_diagnostics +20_util +21_strings +22_locale +23_containers +25_algorithms +26_numerics +27_io +
+ In addition, the following directories include test files: +
+tr1 Tests for components as described by the Technical Report on Standard Library Extensions (TR1). +backward Tests for backwards compatibility and deprecated features. +demangle Tests for __cxa_demangle, the IA 64 C++ ABI demangler +ext Tests for extensions. +performance Tests for performance analysis, and performance regressions. +thread Tests for threads. +
+ Some directories don't have test files, but instead contain + auxiliary information (more information): +
+config Files for the dejagnu test harness. +lib Files for the dejagnu test harness. +libstdc++* Files for the dejagnu test harness. +data Sample text files for testing input and output. +util Files for libtestc++, utilities and testing routines. +
+ Within a directory that includes test files, there may be
+ additional subdirectories, or files. Originally, test cases
+ were appended to one file that represented a particular section
+ of the chapter under test, and was named accordingly. For
+ instance, to test items related to 21.3.6.1 -
+ basic_string::find [lib.string::find] in the standard,
+ the following was used:
+
+21_strings/find.cc +
+ However, that practice soon became a liability as the test cases + became huge and unwieldy, and testing new or extended + functionality (like wide characters or named locales) became + frustrating, leading to aggressive pruning of test cases on some + platforms that covered up implementation errors. Now, the test + suite has a policy of one file, one test case, which solves the + above issues and gives finer grained results and more manageable + error debugging. As an example, the test case quoted above + becomes: +
+21_strings/basic_string/find/char/1.cc +21_strings/basic_string/find/char/2.cc +21_strings/basic_string/find/char/3.cc +21_strings/basic_string/find/wchar_t/1.cc +21_strings/basic_string/find/wchar_t/2.cc +21_strings/basic_string/find/wchar_t/3.cc +
+ All new tests should be written with the policy of one test + case, one file in mind. +
+ In addition, there are some special names and suffixes that are + used within the testsuite to designate particular kinds of + tests. +
+ _xin.cc +
+ This test case expects some kind of interactive input in order + to finish or pass. At the moment, the interactive tests are not + run by default. Instead, they are run by hand, like: +
+g++ 27_io/objects/char/3_xin.cc +cat 27_io/objects/char/3_xin.in | a.out +
+ .in +
+ This file contains the expected input for the corresponding + _xin.cc test case. +
+ _neg.cc +
+ This test case is expected to fail: it's a negative test. At the + moment, these are almost always compile time errors. +
+ char +
+ This can either be a directory name or part of a longer file
+ name, and indicates that this file, or the files within this
+ directory are testing the char instantiation of a
+ template.
+
+ wchar_t +
+ This can either be a directory name or part of a longer file
+ name, and indicates that this file, or the files within this
+ directory are testing the wchar_t instantiation of
+ a template. Some hosts do not support wchar_t
+ functionality, so for these targets, all of these tests will not
+ be run.
+
+ thread +
+ This can either be a directory name or part of a longer file + name, and indicates that this file, or the files within this + directory are testing situations where multiple threads are + being used. +
+ performance +
+ This can either be an enclosing directory name or part of a + specific file name. This indicates a test that is used to + analyze runtime performance, for performance regression testing, + or for other optimization related analysis. At the moment, these + test cases are not run by default. +
+ You can check the status of the build without installing it + using the dejagnu harness, much like the rest of the gcc + tools.
make check
in the libbuilddir directory.
or
make check-target-libstdc++-v3
in the gccbuilddir directory. +
+ These commands are functionally equivalent and will create a + 'testsuite' directory underneath + libbuilddir containing the results of the + tests. Two results files will be generated: + libstdc++.sum, which is a PASS/FAIL summary for each + test, and libstdc++.log which is a log of + the exact command line passed to the compiler, the compiler + output, and the executable output (if any). +
+ Archives of test results for various versions and platforms are + available on the GCC website in the build + status section of each individual release, and are also + archived on a daily basis on the gcc-testresults + mailing list. Please check either of these places for a similar + combination of source version, operating system, and host CPU. +
+ There are several options for running tests, including testing + the regression tests, testing a subset of the regression tests, + testing the performance tests, testing just compilation, testing + installed tools, etc. In addition, there is a special rule for + checking the exported symbols of the shared library. +
+ To debug the dejagnu test harness during runs, try invoking with a + specific argument to the variable RUNTESTFLAGS, as below. +
+make check-target-libstdc++-v3 RUNTESTFLAGS="-v" +
+ or +
+make check-target-libstdc++-v3 RUNTESTFLAGS="-v -v" +
+ To run a subset of the library tests, you will need to generate + the testsuite_files file by running + make testsuite_files in the + libbuilddir/testsuite directory, described + below. Edit the file to remove the tests you don't want and + then run the testsuite as normal. +
+ There are two ways to run on a simulator: set up DEJAGNU to point to a + specially crafted site.exp, or pass down --target_board flags. +
+ Example flags to pass down for various embedded builds are as follows: +
+ --target=powerpc-eabism (libgloss/sim) +make check-target-libstdc++-v3 RUNTESTFLAGS="--target_board=powerpc-sim" + +--target=calmrisc32 (libgloss/sid) +make check-target-libstdc++-v3 RUNTESTFLAGS="--target_board=calmrisc32-sid" + +--target=xscale-elf (newlib/sim) +make check-target-libstdc++-v3 RUNTESTFLAGS="--target_board=arm-sim" +
+ Also, here is an example of how to run the libstdc++ testsuite + for a multilibed build directory with different ABI settings: +
+make check-target-libstdc++-v3 RUNTESTFLAGS='--target_board \"unix{-mabi=32,,-mabi=64}\"'
+
+ You can run the tests with a compiler and library that have
+ already been installed. Make sure that the compiler (e.g.,
+ g++) is in your PATH. If you are
+ using shared libraries, then you must also ensure that the
+ directory containing the shared version of libstdc++ is in your
+ LD_LIBRARY_PATH, or equivalent. If your GCC source
+ tree is at /path/to/gcc, then you can run the tests
+ as follows:
+
+runtest --tool libstdc++ --srcdir=/path/to/gcc/libstdc++-v3/testsuite +
+ The testsuite will create a number of files in the directory in + which you run this command,. Some of those files might use the + same name as files created by other testsuites (like the ones + for GCC and G++), so you should not try to run all the + testsuites in parallel from the same directory. +
+ In addition, there are some testing options that are mostly of + interest to library maintainers and system integrators. As such, + these tests may not work on all cpu and host combinations, and + may need to be executed in the + libbuilddir/testsuite directory. These + options include, but are not necessarily limited to, the + following: +
+ make testsuite_files +
+ Five files are generated that determine what test files + are run. These files are: +
+ testsuite_files +
+ This is a list of all the test cases that will be run. Each + test case is on a separate line, given with an absolute path + from the libsrcdir/testsuite directory. +
+ testsuite_files_interactive +
+ This is a list of all the interactive test cases, using the + same format as the file list above. These tests are not run + by default. +
+ testsuite_files_performance +
+ This is a list of all the performance test cases, using the + same format as the file list above. These tests are not run + by default. +
+ testsuite_thread +
+ This file indicates that the host system can run tests which + involved multiple threads. +
+ testsuite_wchar_t +
+ This file indicates that the host system can run the wchar_t
+ tests, and corresponds to the macro definition
+ _GLIBCXX_USE_WCHAR_T in the file c++config.h.
+
+ make check-abi +
+ The library ABI can be tested. This involves testing the shared + library against an ABI-defining previous version of symbol + exports. +
+ make check-compile +
+ This rule compiles, but does not link or execute, the + testsuite_files test cases and displays the + output on stdout. +
+ make check-performance +
+ This rule runs through the + testsuite_files_performance test cases and + collects information for performance analysis and can be used to + spot performance regressions. Various timing information is + collected, as well as number of hard page faults, and memory + used. This is not run by default, and the implementation is in + flux. +
+ We are interested in any strange failures of the testsuite; + please email the main libstdc++ mailing list if you see + something odd or have questions. +
+ To run the libstdc++ test suite under the debug mode, edit
+ libstdc++-v3/scripts/testsuite_flags to add the
+ compile-time flag -D_GLIBCXX_DEBUG to the
+ result printed by the --build-cxx
+ option. Additionally, add the
+ -D_GLIBCXX_DEBUG_PEDANTIC flag to turn on
+ pedantic checking. The libstdc++ test suite should produce
+ precisely the same results under debug mode that it does under
+ release mode: any deviation indicates an error in either the
+ library or the test suite.
+
+ The parallel
+ mode can be tested in much the same manner, substituting
+ -D_GLIBCXX_PARALLEL for
+ -D_GLIBCXX_DEBUG in the previous paragraph.
+
+ Or, just run the testsuites with CXXFLAGS
+ set to -D_GLIBCXX_DEBUG or
+ -D_GLIBCXX_PARALLEL.
+
+ The first step in making a new test case is to choose the correct + directory and file name, given the organization as previously + described. +
+ All files are copyright the FSF, and GPL'd: this is very + important. The first copyright year should correspond to the date + the file was checked in to SVN. +
+ As per the dejagnu instructions, always return 0 from main to + indicate success. +
+ A bunch of utility functions and classes have already been
+ abstracted out into the testsuite utility library,
+ libtestc++. To use this functionality, just include the
+ appropriate header file: the library or specific object files will
+ automatically be linked in as part of the testsuite run.
+
+ For a test that needs to take advantage of the dejagnu test + harness, what follows below is a list of special keyword that + harness uses. Basically, a test case contains dg-keywords (see + dg.exp) indicating what to do and what kinds of behavior are to be + expected. New test cases should be written with the new style + DejaGnu framework in mind. +
+ To ease transition, here is the list of dg-keyword documentation + lifted from dg.exp. +
+# The currently supported options are:
+#
+# dg-prms-id N
+# set prms_id to N
+#
+# dg-options "options ..." [{ target selector }]
+# specify special options to pass to the tool (eg: compiler)
+#
+# dg-do do-what-keyword [{ target/xfail selector }]
+# `do-what-keyword' is tool specific and is passed unchanged to
+# ${tool}-dg-test. An example is gcc where `keyword' can be any of:
+# preprocess|compile|assemble|link|run
+# and will do one of: produce a .i, produce a .s, produce a .o,
+# produce an a.out, or produce an a.out and run it (the default is
+# compile).
+#
+# dg-error regexp comment [{ target/xfail selector } [{.|0|linenum}]]
+# indicate an error message <regexp> is expected on this line
+# (the test fails if it doesn't occur)
+# Linenum=0 for general tool messages (eg: -V arg missing).
+# "." means the current line.
+#
+# dg-warning regexp comment [{ target/xfail selector } [{.|0|linenum}]]
+# indicate a warning message <regexp> is expected on this line
+# (the test fails if it doesn't occur)
+#
+# dg-bogus regexp comment [{ target/xfail selector } [{.|0|linenum}]]
+# indicate a bogus error message <regexp> use to occur here
+# (the test fails if it does occur)
+#
+# dg-build regexp comment [{ target/xfail selector }]
+# indicate the build use to fail for some reason
+# (errors covered here include bad assembler generated, tool crashes,
+# and link failures)
+# (the test fails if it does occur)
+#
+# dg-excess-errors comment [{ target/xfail selector }]
+# indicate excess errors are expected (any line)
+# (this should only be used sparingly and temporarily)
+#
+# dg-output regexp [{ target selector }]
+# indicate the expected output of the program is <regexp>
+# (there may be multiple occurrences of this, they are concatenated)
+#
+# dg-final { tcl code }
+# add some tcl code to be run at the end
+# (there may be multiple occurrences of this, they are concatenated)
+# (unbalanced braces must be \-escaped)
+#
+# "{ target selector }" is a list of expressions that determine whether the
+# test succeeds or fails for a particular target, or in some cases whether the
+# option applies for a particular target. If the case of `dg-do' it specifies
+# whether the test case is even attempted on the specified target.
+#
+# The target selector is always optional. The format is one of:
+#
+# { xfail *-*-* ... } - the test is expected to fail for the given targets
+# { target *-*-* ... } - the option only applies to the given targets
+#
+# At least one target must be specified, use *-*-* for "all targets".
+# At present it is not possible to specify both `xfail' and `target'.
+# "native" may be used in place of "*-*-*".
+
+Example 1: Testing compilation only
+// { dg-do compile }
+
+Example 2: Testing for expected warnings on line 36, which all targets fail
+// { dg-warning "string literals" "" { xfail *-*-* } 36
+
+Example 3: Testing for expected warnings on line 36
+// { dg-warning "string literals" "" { target *-*-* } 36
+
+Example 4: Testing for compilation errors on line 41
+// { dg-do compile }
+// { dg-error "no match for" "" { target *-*-* } 41 }
+
+Example 5: Testing with special command line settings, or without the
+use of pre-compiled headers, in particular the stdc++.h.gch file. Any
+options here will override the DEFAULT_CXXFLAGS and PCH_CXXFLAGS set
+up in the normal.exp file.
+// { dg-options "-O0" { target *-*-* } }
++ More examples can be found in the libstdc++-v3/testsuite/*/*.cc files. +
+ Underlying details of testing for conformance and regressions are + abstracted via the GNU Dejagnu package. This is similar to the + rest of GCC. +
This is information for those looking at making changes to the testsuite +structure, and/or needing to trace dejagnu's actions with --verbose. This +will not be useful to people who are "merely" adding new tests to the existing +structure. +
The first key point when working with dejagnu is the idea of a "tool". +Files, directories, and functions are all implicitly used when they are +named after the tool in use. Here, the tool will always be "libstdc++". +
The lib subdir contains support routines. The
+lib/libstdc++.exp file ("support library") is loaded
+automagically, and must explicitly load the others. For example, files can
+be copied from the core compiler's support directory into lib.
+
Some routines in lib/libstdc++.exp are callbacks, some are
+our own. Callbacks must be prefixed with the name of the tool. To easily
+distinguish the others, by convention our own routines are named "v3-*".
+
The next key point when working with dejagnu is "test files". Any
+directory whose name starts with the tool name will be searched for test files.
+(We have only one.) In those directories, any .exp file is
+considered a test file, and will be run in turn. Our main test file is called
+normal.exp; it runs all the tests in testsuite_files using the
+callbacks loaded from the support library.
+
The config directory is searched for any particular "target
+board" information unique to this library. This is currently unused and sets
+only default variables.
+
+
+ The testsuite directory also contains some files that implement + functionality that is intended to make writing test cases easier, + or to avoid duplication, or to provide error checking in a way that + is consistent across platforms and test harnesses. A stand-alone + executable, called abi_check, and a static + library called libtestc++ are + constructed. Both of these items are not installed, and only used + during testing. +
+ These files include the following functionality: +
+ testsuite_abi.h, + testsuite_abi.cc, + testsuite_abi_check.cc +
+ Creates the executable abi_check. + Used to check correctness of symbol versioning, visibility of + exported symbols, and compatibility on symbols in the shared + library, for hosts that support this feature. More information + can be found in the ABI documentation here +
+ testsuite_allocator.h, + testsuite_allocator.cc +
+ Contains specialized allocators that keep track of construction + and destruction. Also, support for overriding global new and + delete operators, including verification that new and delete + are called during execution, and that allocation over max_size + fails. +
+ testsuite_character.h +
+ Contains std::char_traits and
+ std::codecvt specializations for a user-defined
+ POD.
+
+ testsuite_hooks.h, + testsuite_hooks.cc +
+ A large number of utilities, including: +
VERIFY
set_memory_limits
verify_demangle
run_tests_wrapped_locale
run_tests_wrapped_env
try_named_locale
try_mkfifo
func_callback
counter
copy_tracker
copy_constructor
assignment_operator
destructor
pod_char, pod_int and associated char_traits specializations
+ testsuite_io.h +
+ Error, exception, and constraint checking for
+ std::streambuf, std::basic_stringbuf, std::basic_filebuf.
+
+ testsuite_iterators.h +
+ Wrappers for various iterators. +
+ testsuite_performance.h +
+ A number of class abstractions for performance counters, and + reporting functions including: +
time_counter
resource_counter
report_performance