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Date:   Tue, 20 Aug 2019 22:39:39 +0200
From:   Peter Zijlstra <peterz@infradead.org>
To:     "Paul E. McKenney" <paulmck@linux.ibm.com>
Cc:     Linus Torvalds <torvalds@linux-foundation.org>,
        Valentin Schneider <valentin.schneider@arm.com>,
        Joel Fernandes <joel@joelfernandes.org>,
        Thomas Gleixner <tglx@linutronix.de>,
        Alan Stern <stern@rowland.harvard.edu>,
        Mathieu Desnoyers <mathieu.desnoyers@efficios.com>,
        rostedt <rostedt@goodmis.org>,
        linux-kernel <linux-kernel@vger.kernel.org>,
        Boqun Feng <boqun.feng@gmail.com>,
        Will Deacon <will.deacon@arm.com>,
        David Howells <dhowells@redhat.com>
Subject: Re: [PATCH 1/1] Fix: trace sched switch start/stop racy updates
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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 :-)