On 17/07/2024 19:51, Junio C Hamano wrote: > Ramsay Jones <ramsay@xxxxxxxxxxxxxxxxxxxx> writes: [snip] >> I mentioned this problem to Luc on the sparse mailing list[1] and >> he produced a patch which 'fixed' the problem in one way, but >> caused a different problem[2]. Namely, because git passes -Wvla >> to gcc, it now issues the 'used vla' warnings, which gcc does >> not because of some '# pragma GCC diagnostic ignored "-Wvla"' which >> sparse does not honor! :( > > Sorry, but I do not follow. Isn't -Wno-vla an instruction to sparse > to tell it *not* to complain about use of vla? It's a warning flag for both sparse and gcc. At the time, I was trying to find a solution which didn't disable the warning for gcc at the same time (iff you used sparse as a front-end to gcc, which people on git tend not to do; ie _don't_ use 'cgcc -no-compile' ;) ). Also, I wanted a solution that didn't require setting SPARSE_FLAGS (SP_EXTRA_FLAGS didn't exist then) in the Makefile (only some people were affected). > We do not pass -Wvla or -Wno-vla to sparse ourselves. Because the > tool comes from the Linux land where VLA is not welcome, we'd by > default get the "hey, you used vla here---did you mean it?" error. > > And the patch by Luc Van Oostenryck in the thread you raised at > around the end of 2023 does apply to the tip and with > > SP_EXTRA_FLAGS += -Wno-vla > > in Makefile, sparse seems to be happy when I do "make sparse". Yes, that works because 'make sparse' does not use cgcc as a front end to gcc, and the command line has -Wvla followed by -Wno-vla, so last one wins (the sparse specific flags come after the gcc flags). ATB, Ramsay Jones
