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Re: , operand with no effect warning

To: Phil Edwards <pedwards at disaster dot jaj dot com>
Subject: Re: , operand with no effect warning
From: Fergus Henderson <fjh at cs dot mu dot oz dot au>
Date: Tue, 31 Jul 2001 09:14:56 +1000
Cc: John Levon <moz at compsoc dot man dot ac dot uk>, gcc at gcc dot gnu dot org
References: <20010730203002.A6393@compsoc.man.ac.uk> <20010730180111.C22291@disaster.jaj.com>

On 30-Jul-2001, Phil Edwards <pedwards@disaster.jaj.com> wrote:
> On Mon, Jul 30, 2001 at 08:30:03PM +0100, John Levon wrote:
> > 
> > Why does gcc warn for :
> > 
> > 	p1, p2;
> 
> Because this has no effect.
> 
> > but not :
> > 	delete p1, p2;
> 
> Because this does have an effect.

Yes, but it contains a subexpression whose result is discarded
and which has no side effects.  It should get a warning.

-- 
Fergus Henderson <fjh@cs.mu.oz.au>  |  "I have always known that the pursuit
The University of Melbourne         |  of excellence is a lethal habit"
WWW: <http://www.cs.mu.oz.au/~fjh>  |     -- the last words of T. S. Garp.

References:
- , operand with no effect warning
  - From: John Levon
- Re: , operand with no effect warning
  - From: Phil Edwards

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