From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id A13252DF707; Thu, 26 Mar 2026 22:17:07 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1774563427; cv=none; b=ojCQ3eNIEmTnJB654INHKh91l9UaZ711JWLZ44CkIt+b+TIu+2+XbzB/061T9vTJ4Ic6/A7AOZoO63Lg4tv//4lXKDtzW6D3AaMc0QmKoVjEtFmY0tpdbiCAwntcWV+99vd66XcpzyNCQrOXTjFNnZjgO4edBS9YG2CTLofe1R0= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1774563427; c=relaxed/simple; bh=0Pwt+rO6OsFNN5h5KMkxEfyuwSQF+emiQKruEarJj0g=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=Q7jRglFUI35N1whkratUKUWGCmFvRuI4di8rucB7V73QD4eYDWCrfvHS97CnxVsOr9LW+JPS0zHvjJwhQxxoy4wZeTFJH3tj0raq1oW3nfby99p8tsfdto+nTD0O+TLo6UVorjDPiitNJN/bmX3COkOin+9c3tzyadBNqwxpE2w= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=o6GB4skY; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="o6GB4skY" Received: by smtp.kernel.org (Postfix) with ESMTPSA id AB8A4C116C6; Thu, 26 Mar 2026 22:17:06 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1774563427; bh=0Pwt+rO6OsFNN5h5KMkxEfyuwSQF+emiQKruEarJj0g=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=o6GB4skYj4JeICc0QmDD9guUtkiv5/feswjTmRm+67sjHMpPNuJUeEZGwCuD+XyYO mFOqwMEiRFwBQ9RJaleYZrVJh+DQjeMqRaDmLwnAsYOYlXzzGJN1opKy02SfUIBn5y 9tchyL5sUIE/DYfY+zZImWrtfLZknuhac2Q8ihKVgwFnEx6OpGw+aEf1ddaLO4hlrP 0Em+oZXveKDz4JViSO6/gT4OMxAaUqXgRsKarx+/nEMseM9E3U1t3kgt7TT0LiRe89 sHGtqCOTaCnKNzc2zuCDUpDX0NnQPKMG37uUyWD8SKM0gH/OIgvP8vkFueERb+e9B0 eczi3UhNK8LbA== Date: Thu, 26 Mar 2026 15:17:05 -0700 From: Namhyung Kim To: Ian Rogers Cc: Peter Zijlstra , Ingo Molnar , Arnaldo Carvalho de Melo , Jiri Olsa , Adrian Hunter , James Clark , linux-perf-users@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH v1] perf build: Add -funsigned-char to default CFLAGS Message-ID: References: <20260306191908.2065682-1-irogers@google.com> Precedence: bulk X-Mailing-List: linux-perf-users@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: On Fri, Mar 20, 2026 at 04:00:56PM -0700, Ian Rogers wrote: > On Fri, Mar 6, 2026 at 11:19 AM Ian Rogers 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 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 > >