|Testing with QMTest
|You can use QMTest to test G++. (In the future, it may be possible to
|test other parts of GCC with QMTest as well, but it is not possible
|The use of QMTest to run the G++ tests has not been approved as an
|officially supported testing procedure. Therefore, you must run the
|tests using DejaGNU (with "make check-g++") before committing changes
|that affect G++.
|QMTest emulates DejaGNU behavior very closely when running the tests.
|QMTest has two output modes: a DejaGNU emulation mode and a native
|In the DejaGNU mode, you should receive output that is almost exactly
|the same as the DejaGNU output; in particular, you should see the same
|number of passes, failures, etc. When using the DejaGNU-style output,
|QMTest uses the "xfail" indications in the test cases to determine
|which tests are expected to pass and which are expected to fail, and
|presents that information in the same way as DejaGNU.
|In the QMTest mode, the number of passes and failures will be
|different from that obtained when using DejaGNU. The reason is that a
|single source file may contain multiple DejaGNU tests. In DejaGNU,
|each line where a diagnostic is expected is considered a separate
|test. Testing for successful compilation and testing for successful
|execution of the generated program are considered separate tests. So,
|a single source file "test.C" could contain, say, seven tests; some of
|which might pass and some of which might fail.
|In the QMTest mode, each source file is considered a single test. If
|any of the seven sub-tests fail, the entire test is considered to
|fail. However, QMTest does present information about *why* the test
|failed, so the same information is effectively available.
|In the QMTest mode, whether or not a test is expected to fail is
|determined not by an indication in the test, but rather by comparing
|the new results to the results of a previous run. Testing for whether
|a change caused a regression is very simple: run the tests before
|making the change, run them again after making the change, and let
|QMTest compare the results.
|The mode chosen only affects the output from QMTest, not how it runs
|the tests or how it stores the data. Therefore, if you choose to run
|in the QMTest mode and later want to get the DejaGNU style output, or
|vice versa, you can do that as described below.
|You must download and install the following software:
|- Python 2.2 (or greater)
|You may already have Python on your system; in particular, many
|GNU/Linux systems ship with Python installed.
|Installation instructions are available on the web-site.
|- A current version of QMTest. No released version provides all of
|the functionality required, so you must obtain QMTest from CVS.
|To do that, follow the instructions at:
|Installation instructions are available in the file called README
|after you check out QMTest.
|- The "qmtc" and "qmtest_gcc" QMTest support packages. These are
|available from the same CVS repository as QMTest. For example, to
|check out "qmtc", do:
|cvs -d :pserver:email@example.com:/home/qm/Repository \
|You do not have to install these packages; you need only check them
|Running the Tests
|First, you must set QMTEST_CLASS_PATH so that it can find the qmtc and
|qmtest_gcc support packages:
|The, run "make qmtest-g++" in the gcc directory of your build tree.
|Here are some more advanced usage instructions:
|1. To run a particular set of tests (rather than all of the tests),
|use the make variable "QMTEST_GPP_TESTS". For example,
|make QMTEST_GPP_TESTS="g++.dg" qmtest-g++
|will run only the tests in the g++.dg subdirectory, and:
|make QMTEST_GPP_TESTS="g++.dg/special/conpr-1.C \
|will run only the two tests indicated.
|2. To run qmtest with particular flags, use the make variables
|"QMTESTFLAGS" and "QMTESTRUNFLAGS". For example:
|make QMTESTFLAGS="-v" QMTESTRUNFLAGS="-f full" qmtest-g++
|will run qmtest like this:
|qmtest -v run -f full ...
|(The "-f full" mode will provide detailed information about each
|test as it runs.)
|3. To run the compiler with particular flags, use QMTESTRUNFLAGS to
|set the QMTest context variable "CompilerTable.cplusplus_options",
|QMTESTRUNFLAGS='-c CompilerTable.cplusplus_options="-funroll-loops"' \
|The compiler will then use the "-funroll-loops" switch when
|4. If qmtest is not in your path, you can indicate the full path to
|QMTest by using the make variable "QMTEST_PATH", like this:
|make QMTEST_PATH=/path/to/qmtest qmtest-g++
|5. To start the QMTest GUI, use:
|(Note that this will run the program called "mozilla" in your path.
|If you want to use another browser, you must configure qmtest as
|described in its manual.)
|Bear in mind that the QMTest GUI is insecure; malicious users with
|access to your machine may be able to run commands as if they were
|you. The QMTest GUI only binds to the loopback IP addresss, which
|provides a measure of security, but not enough for use in untrusted
|6. If you have a multiprocessor, you can run the tests in parallel by
|passing the "-j" option to qmtest:
|make QMTESTRUNFLAGS="-j 4" qmtest-g++
|will run tests in four threads. (It is also possible to run tests
|across multiple machines; for more information see the QMTest
|7. If a test (say "g++.dg/abi/bitfield1.C") fails, and you want to get
|more detailed information, you can do:
|qmtest summarize g++.qmr g++.dg/abi/bitfield1.C
|to get more information about the commands that were run and the