From: Namhyung Kim <namhyung@kernel.org>
To: Ian Rogers <irogers@google.com>
Cc: Peter Zijlstra <peterz@infradead.org>,
Ingo Molnar <mingo@redhat.com>,
Arnaldo Carvalho de Melo <acme@kernel.org>,
Jiri Olsa <jolsa@kernel.org>,
Adrian Hunter <adrian.hunter@intel.com>,
James Clark <james.clark@linaro.org>,
linux-perf-users@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH v1] perf build: Add -funsigned-char to default CFLAGS
Date: Thu, 26 Mar 2026 15:17:05 -0700 [thread overview]
Message-ID: <acWwYcn3QAznaw4x@google.com> (raw)
In-Reply-To: <CAP-5=fUWOKFwHZKYUv3ntxaPb1aFEEmSdo4npfe9oG3EPn7qBA@mail.gmail.com>
On Fri, Mar 20, 2026 at 04:00:56PM -0700, Ian Rogers wrote:
> On Fri, Mar 6, 2026 at 11:19 AM Ian Rogers <irogers@google.com> wrote:
> >
> > Commit 3bc753c06dd0 ("kbuild: treat char as always unsigned") made
> > chars unsigned by default in the Linux kernel. To avoid similar kinds
> > of bugs and warnings, make unsigned chars the default for the perf tool.
> >
> > Signed-off-by: Ian Rogers <irogers@google.com>
Do you know what the actual bug was?
Thanks,
Namhyung
>
> > ---
> > tools/perf/Makefile.config | 1 +
> > 1 file changed, 1 insertion(+)
> >
> > diff --git a/tools/perf/Makefile.config b/tools/perf/Makefile.config
> > index a8dc72cfe48e..3820bdf73f43 100644
> > --- a/tools/perf/Makefile.config
> > +++ b/tools/perf/Makefile.config
> > @@ -349,6 +349,7 @@ CORE_CFLAGS += -fno-omit-frame-pointer
> > CORE_CFLAGS += -Wall
> > CORE_CFLAGS += -Wextra
> > CORE_CFLAGS += -std=gnu11
> > +CORE_CFLAGS += -funsigned-char
> >
> > CXXFLAGS += -std=gnu++17 -fno-exceptions -fno-rtti
> > CXXFLAGS += -Wall
> > --
> > 2.53.0.473.g4a7958ca14-goog
> >
next prev parent reply other threads:[~2026-03-26 22:17 UTC|newest]
Thread overview: 4+ messages / expand[flat|nested] mbox.gz Atom feed top
2026-03-06 19:19 [PATCH v1] perf build: Add -funsigned-char to default CFLAGS Ian Rogers
2026-03-20 23:00 ` Ian Rogers
2026-03-26 22:17 ` Namhyung Kim [this message]
2026-03-26 23:18 ` Ian Rogers
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