On Fri, Jun 07, 2024 at 04:24:28PM +0100, Al Viro wrote:
> > >> fs/select.c:860:3: error: cannot jump from this goto statement to its label
> > 860 | goto out;
> > | ^
> > fs/select.c:862:12: note: jump bypasses initialization of variable with __attribute__((cleanup))
> > 862 | CLASS(fd, f)(fd);
> > | ^
> > 13 warnings and 1 error generated.
>
> Sigh... That's why declarations in the middle of block really stink.
> Sadly, the use of CLASS() very much invites that kind of crap.
> For this series I decided to suppress the gag reflex and see how
> it goes, but... ouch.
>
> Worse, neither current gcc, nor clang 14 catch that kind of crap ;-/
Hmmm, I am able to reproduce this with clang 14.0.6 from kernel.org [1]
with x86_64 allnoconfig:
$ make -skj"$(nproc)" ARCH=x86_64 LLVM=1 allnoconfig fs/select.o
fs/select.c:860:3: error: cannot jump from this goto statement to its label
goto out;
^
fs/select.c:862:12: note: jump bypasses initialization of variable with __attribute__((cleanup))
CLASS(fd, f)(fd);
^
1 error generated.
$ clang --version | head -1
ClangBuiltLinux clang version 14.0.6 (https://github.com/llvm/llvm-project f28c006a5895fc0e329fe15fead81e37457cb1d1)
It is a bug that GCC does not warn about this as far as I understand it:
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=91951
[1]: https://mirrors.edge.kernel.org/pub/tools/llvm/
Cheers,
Nathan
