New compiler warnings in 9.1.444 about vim

[chrisbra]

I noticed this to with gcc-10. I stared at it for a while and couldn't make sense of it. It only seems to occur when compiling with -O2 (which is unfortunately the default). I suspect a false positive here, because it doesn't appear when compiling with -O (or when compiling with clang) and the code seems correct. However I am not sure if the optimizer optimizes the code wrongly and then the warning is justified (and this is an actual issue with the optimized code). So I am not sure what to do against it.

It's the reason I commited 95ff39f to make sure coverity still works.

[chrisbra]

BTW: what gcc version are you using? I see it with gcc-10 on my default Debian bulleye work-station. On a bookworm with gcc-13, I don't see this warning.

[chdiza]

$ gcc --version
gcc (Ubuntu 11.4.0-1ubuntu1~22.04) 11.4.0

[chrisbra]

I don't see it with gcc-13. and gcc-12. Seems an issue with gcc-10 and gcc-11 then. Does the workaround of export CFLAGS=-O and then configure, make work for you?

[chdiza]

That workaround does seem to prevent the warning. I'm not sure whether I should use that workaround; without the workaround and with the warning, vim ends up compiling anyway.