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McKenney" Cc: Linus Torvalds , Valentin Schneider , Joel Fernandes , Thomas Gleixner , Alan Stern , Mathieu Desnoyers , rostedt , linux-kernel , Boqun Feng , Will Deacon , David Howells Subject: Re: [PATCH 1/1] Fix: trace sched switch start/stop racy updates Message-ID: <20190820203939.GV2349@hirez.programming.kicks-ass.net> References: <241506096.21688.1565977319832.JavaMail.zimbra@efficios.com> <20190816205740.GF10481@google.com> <3c0cb8a2-eba2-7bea-8523-b948253a6804@arm.com> <20190817045217.GZ28441@linux.ibm.com> <20190820140116.GT2332@hirez.programming.kicks-ass.net> <20190820203135.GX28441@linux.ibm.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20190820203135.GX28441@linux.ibm.com> User-Agent: Mutt/1.10.1 (2018-07-13) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Aug 20, 2019 at 01:31:35PM -0700, Paul E. McKenney wrote: > On Tue, Aug 20, 2019 at 04:01:16PM +0200, Peter Zijlstra wrote: > > We really should get the compiler folks to give us a > > -fno-pointer-provenance. Waiting on the standards committee to get their > > act together seems unlikely, esp. given that some people actually seem > > to _want_ this nonsense :/ > > The reason that they want it is to enable some significant optimizations > in numerical code on the one hand and in heavily templated C++ code on > the other. Neither of which has much bearing on kernel code. > > Interested in coming to the next C standards committee meeting in October > to help me push for this? ;-) How about we try and get some compiler folks together at plumbers and bribe them with beer? Once we have our compiler knob, we happy :-)