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Date: Mon, 25 Jun 2012 06:20:37 -0700
From: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
To: David Rientjes <rientjes@google.com>
Cc: Cong Wang <xiyou.wangcong@gmail.com>,
        Fengguang Wu <fengguang.wu@intel.com>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>
Subject: Re: BUG: tracer_alloc_buffers returned with preemption imbalance
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On Mon, Jun 25, 2012 at 02:10:23AM -0700, David Rientjes wrote:
> On Sun, 24 Jun 2012, Paul E. McKenney wrote:
> 
> > But in my case, the trailing preempt_enable() should not have been
> > optimized away, right?  Wouldn't it be more like the following?
> > 
> > int a = 0;
> > int main(void)
> > {
> > 	a++;
> > 	return ++a;
> > 	a++;
> > }
> > 
> > Hmmm...  But this -still- doesn't emit any warnings.
> > 
> 
> gcc removed -Wunreachable-code a couple years ago.  It doesn't complain 
> when you pass it for backwards compatibility with old Makefiles.

Ah well, back to manual inspection, then.  :-/

							Thanx, Paul