Message-ID: <Z-7RDmHVWqJWS1aV@thinkpad>
Date: Thu, 3 Apr 2025 14:18:54 -0400
From: Yury Norov <yury.norov@...il.com>
To: Ian Rogers <irogers@...gle.com>
Cc: Rasmus Villemoes <linux@...musvillemoes.dk>,
	Peter Zijlstra <peterz@...radead.org>,
	Ingo Molnar <mingo@...hat.com>,
	Arnaldo Carvalho de Melo <acme@...nel.org>,
	Namhyung Kim <namhyung@...nel.org>,
	Mark Rutland <mark.rutland@....com>,
	Alexander Shishkin <alexander.shishkin@...ux.intel.com>,
	Jiri Olsa <jolsa@...nel.org>,
	Adrian Hunter <adrian.hunter@...el.com>,
	Kan Liang <kan.liang@...ux.intel.com>,
	Thomas Gleixner <tglx@...utronix.de>,
	Darren Hart <dvhart@...radead.org>,
	Davidlohr Bueso <dave@...olabs.net>,
	André Almeida <andrealmeid@...lia.com>,
	John Garry <john.g.garry@...cle.com>, Will Deacon <will@...nel.org>,
	James Clark <james.clark@...aro.org>,
	Mike Leach <mike.leach@...aro.org>, Leo Yan <leo.yan@...ux.dev>,
	Yicong Yang <yangyicong@...ilicon.com>,
	Jonathan Cameron <jonathan.cameron@...wei.com>,
	Nathan Chancellor <nathan@...nel.org>,
	Bill Wendling <morbo@...gle.com>,
	Justin Stitt <justinstitt@...gle.com>,
	Josh Poimboeuf <jpoimboe@...nel.org>,
	Al Viro <viro@...iv.linux.org.uk>, Kyle Meyer <kyle.meyer@....com>,
	Ben Gainey <ben.gainey@....com>,
	Athira Rajeev <atrajeev@...ux.vnet.ibm.com>,
	Kajol Jain <kjain@...ux.ibm.com>,
	Aditya Gupta <adityag@...ux.ibm.com>,
	Eder Zulian <ezulian@...hat.com>,
	Dapeng Mi <dapeng1.mi@...ux.intel.com>,
	Kuan-Wei Chiu <visitorckw@...il.com>, He Zhe <zhe.he@...driver.com>,
	Dirk Gouders <dirk@...ders.net>, Brian Geffon <bgeffon@...gle.com>,
	Ravi Bangoria <ravi.bangoria@....com>,
	Howard Chu <howardchu95@...il.com>,
	Charlie Jenkins <charlie@...osinc.com>,
	Colin Ian King <colin.i.king@...il.com>,
	Dominique Martinet <asmadeus@...ewreck.org>,
	Jann Horn <jannh@...gle.com>,
	Masahiro Yamada <masahiroy@...nel.org>,
	Arnd Bergmann <arnd@...db.de>,
	Yang Jihong <yangjihong@...edance.com>,
	Dmitry Vyukov <dvyukov@...gle.com>, Andi Kleen <ak@...ux.intel.com>,
	Graham Woodward <graham.woodward@....com>,
	Ilkka Koskinen <ilkka@...amperecomputing.com>,
	Anshuman Khandual <anshuman.khandual@....com>,
	Zhongqiu Han <quic_zhonhan@...cinc.com>, Hao Ge <gehao@...inos.cn>,
	Tengda Wu <wutengda@...weicloud.com>,
	Gabriele Monaco <gmonaco@...hat.com>,
	Chun-Tse Shao <ctshao@...gle.com>,
	Casey Chen <cachen@...estorage.com>,
	"Dr. David Alan Gilbert" <linux@...blig.org>,
	Li Huafei <lihuafei1@...wei.com>,
	"Steinar H. Gunderson" <sesse@...gle.com>,
	Levi Yun <yeoreum.yun@....com>, Weilin Wang <weilin.wang@...el.com>,
	Thomas Falcon <thomas.falcon@...el.com>,
	Thomas Richter <tmricht@...ux.ibm.com>,
	Andrew Kreimer <algonell@...il.com>,
	Krzysztof Łopatowski <krzysztof.m.lopatowski@...il.com>,
	Christophe Leroy <christophe.leroy@...roup.eu>,
	Jean-Philippe Romain <jean-philippe.romain@...s.st.com>,
	Junhao He <hejunhao3@...wei.com>,
	"Masami Hiramatsu (Google)" <mhiramat@...nel.org>,
	Xu Yang <xu.yang_2@....com>,
	Steve Clevenger <scclevenger@...amperecomputing.com>,
	Zixian Cai <fzczx123@...il.com>,
	Stephen Brennan <stephen.s.brennan@...cle.com>,
	Yujie Liu <yujie.liu@...el.com>, linux-kernel@...r.kernel.org,
	linux-perf-users@...r.kernel.org,
	linux-arm-kernel@...ts.infradead.org, llvm@...ts.linux.dev
Subject: Re: [PATCH v1 02/48] tools headers: Silence -Wshorten-64-to-32
 warnings

On Thu, Apr 03, 2025 at 11:12:30AM -0700, Ian Rogers wrote:
> On Thu, Apr 3, 2025 at 8:45 AM Ian Rogers <irogers@...gle.com> wrote:
> >
> > On Thu, Apr 3, 2025 at 8:23 AM Yury Norov <yury.norov@...il.com> wrote:
> > >
> > > On Thu, Apr 03, 2025 at 07:52:45AM -0700, Ian Rogers wrote:
> > > > On Thu, Apr 3, 2025 at 7:26 AM Yury Norov <yury.norov@...il.com> wrote:
> > > > >
> > > > > On Thu, Apr 03, 2025 at 10:08:39AM -0400, Yury Norov wrote:
> > > > > > On Tue, Apr 01, 2025 at 11:23:00AM -0700, Ian Rogers wrote:
> > > > > > > The clang warning -Wshorten-64-to-32 can be useful to catch
> > > > > > > inadvertent truncation. In some instances this truncation can lead to
> > > > > > > changing the sign of a result, for example, truncation to return an
> > > > > > > int to fit a sort routine. Silence the warning by making the implicit
> > > > > > > truncation explicit.
> > > > > > >
> > > > > > > Signed-off-by: Ian Rogers <irogers@...gle.com>
> > > > >
> > > > > I'm the first person in the To list, but only a couple patches in the
> > > > > series are related to my area. If you want to move it with me, can you
> > > > > send bitmaps, bitfields etc. separately?
> > > >
> > > > Hi Yury,
> > > >
> > > > If you think it is worthwhile. I did the series to see how prevalent a
> > > > bug was in perf's code - inspired by Leo Yan fixing an instance of it.
> > > > I would prefer not to be on the hook for all the kernel warnings :-)
> > > > Perhaps casts to avoid changing bitmap_weight's type. Unfortunately to
> > > > get to where the perf issues were I needed to clean up header files.
> > > > In the bitmap cases the change is just to make implicit casts explicit
> > > > and I don't know how much value you see in that.
> > >
> > > Your changes  are technically correct (except for non-synced kernel and
> > > tools), make the code cleaner, at least to me, and address pretty valid
> > > compiler's concerns. To me, it's worth to apply.
> >
> > Ok cool. I'll make a separate patch series for them. Sorry for giving
> > you such a long patch series with limited signal to noise.
> 
> Posted here:
> https://lore.kernel.org/lkml/20250403165702.396388-1-irogers@google.com/

Yep, I see. Let's wait for a while for any feedback? If all OK, I'll
move it with my branch.

Powered by blists - more mailing lists