Re: [Bug-time] time-1.8: building with gcc7 and --enable-gcc-warnings fails

[Assaf Gordon]

Hello Jim,

On 2017-11-08 07:35 AM, Jim Meyering wrote:
> Thanks a lot for reviving GNU time and for making a new release.
> Sorry I didn't see this sooner:
> ...
> src/time.c: In function 'getargs':
> src/time.c:664:4: warning: this statement may fall through
> [-Wimplicit-fallthrough=]
>      usage (EXIT_SUCCESS);
>      ^~~~~~~~~~~~~~~~~~~~
> src/time.c:665:2: note: here
>    case 'o':
>    ^~~~

Thanks for the report.

I wonder could this be a false-positive?

The function usage() never returns, it always calls exit(3),
and exit(3) is marked as "__attribute__ ((__noreturn__));".

If I specifically mark usage() as "noreturn",
the warning disappears.

Does gcc-7 not able to deduce the non-return-ness of usage() ?


thanks,
 - assaf