Re: [PATCH] perf tools: Suppress potential format-truncation warning in util/pmu.c

From: Arnaldo Carvalho de Melo
Date: Mon Nov 12 2018 - 11:37:28 EST


Em Sun, Nov 11, 2018 at 06:45:24PM +0000, Ben Hutchings escreveu:
> Depending on which functions are inlined in util/pmu.c, the
> snprintf() calls in perf_pmu__parse_{scale,unit,per_pkg,snapshot}()
> might trigger a warning:
>
> util/pmu.c: In function 'pmu_aliases':
> util/pmu.c:178:31: error: '%s' directive output may be truncated writing up to 255 bytes into a region of size between 0 and 4095 [-Werror=format-truncation=]
> snprintf(path, PATH_MAX, "%s/%s.unit", dir, name);
> ^~
>
> I found this when trying to build perf from Linux 3.16 with gcc 8.
> However I can reproduce the problem in mainline if I force
> __perf_pmu__new_alias() to be inlined.
>
> Suppress this by using scnprintf() as has been done elsewhere in
> perf.

Thanks, applied.

- Arnaldo