On Mon, 11 Sept 2023 at 17:37, Jonathan Wakely via Libstdc++ <libstd...@gcc.gnu.org> wrote: > > This patch series replicates the behaviour of the g++ testsuite, so that > libstdc++ tests can easily be run for multiple different -std options in > a single testsuite run. As described in the updated docs, the -std > options to use for every test can be overridden by setting v3_std_list > in ~/.dejagnurc or $DEJAGNU, or setting $GLIBCXX_TESTSUITE_STDS in the > environment. If not overridden, the default is just to run with > -std=gnu++17 (so that we don't increase the time taken for a full > testsuite run). > > Tests that require a newer standard than C++17 will default to that > newer standard and C++26, so e.g. std::format tests will be run with > both -std=gnu++20 and -std=gnu++26. This does increase the number of > tests, but only for the subset of tests for C++20/23/26 features. If > this is too costly for testers, we can change that (this might be > needed, because the C++20 tests for std::ranges and std::format are > particularly slow to compile). > > Because a correct default will be chosen for tests that require > something newer than C++17, we no longer need dg-options "-std=gnu++20" > or similar in any tests. Removing the explicit -std option allows the > test to be run for later standards via the v3_std_list settings, so that > we can verify that C++20 features still work in C++23 and C++26, for > example. This change already found some tests which failed when run > with a later standard (see r14-3771-gf12e26f3496275). > > Patches 2-13 in the series remove those unnecessary dg-options from > about half the relevant tests, but there are more than 500 others that > still need adjusting. > > We can remove files like testsuite/std/format/functions/format_c++23.cc > which only exist to duplicate existing tests with a different -std > option. We can remove that file now, and rely on format.cc being run > with multiple -std options by libstdc++ maintainers. > > It might also be useful to add a 'make check-quick' target which runs a > small subset of smoke tests with every standard version in v3_std_list. > This would be a suitable target for CI bots and for packagers who want > to verify that a build of GCC is functional, without running the entire > libstdc++ testsuite.
This has been pushed to trunk now.
