fnmatch.c refuse to build with --enable-gcc-warnings

[Charlie Brown]

fnmatch.c refuse to build when I build from diffutils git source (with
latest gnulib source) today, which turns on --enable-gcc-warnings by
default.
coreutils git source won't build, too, for the same reason.

I know I can finish the compilation by .configure
--disable-gcc-warnings. Anyway, I'm not a developer and don't care
much about those warnings :). But it's kind of annoying. And it makes
the point of "turn on warnings for developers" useless, I guess.

So can you fix this warning here? Or is there a way to just turn off
warnings for gnulib files, but leave other source files along?

Thanks a lot!
And thank you for making such good tools!

Sincerely,
王文鑫
Charlie

---------------------------------------------------------------------------------------------------
fnmatch_loop.c:601:23: note: label 'normal_bracket' defined here
                       normal_bracket:
                       ^
fnmatch_loop.c:423:26: note: 'is_range' declared here
                     bool is_range = false;
                          ^
fnmatch_loop.c:268:29: error: jump skips variable initialization
[-Werror=jump-misses-init]
                             goto normal_bracket;
                             ^
fnmatch_loop.c:601:23: note: label 'normal_bracket' defined here
                       normal_bracket:
                       ^
fnmatch_loop.c:423:26: note: 'is_range' declared here
                     bool is_range = false;
                          ^
  CC       mktime.o
cc1: all warnings being treated as errors
make[2]: *** [fnmatch.o] Error 1