Mark Wielaard writes: > I was mostly wondering whether we needed to add an command line argument > like -std=gnu++98 to be sure. But maybe that is all implicit and > standard for all gcc versions anyway. Actually I can't find code that c++98 mode would reject and gnu++98 would allow. -pedantic makes all the difference, and it makes it regardless of the dialect chosen. Which makes it kinda hard to actually test for gnu++98 support. Which I think we formally need, for all the GNU C stuff that we get in C headers ((struct X) {blah, blah}, long long literals, __VA_ARGS__). But GCC happily compiles that in c++98 mode anyway. So, I don't know. Maybe I just compile the test case with -std=gnu++98 and make it "Checking for working C++ compiler that accepts -std=gnu++98"? Clang knows about the option as well, FWIW. Thanks, Petr