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Date: Mon, 20 Jun 2011 10:24:00 -0000
From: Richard Guenther <rguenther@suse.de>
To: Michael Matz <matz@suse.de>
Cc: Richard Guenther <richard.guenther@gmail.com>,	Mike Stump <mikestump@comcast.net>, Jason Merrill <jason@redhat.com>,	gcc-patches List <gcc-patches@gcc.gnu.org>
Subject: Re: RFA (fold): PATCH for c++/49290 (folding *(T*)(ar+10))
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On Fri, 17 Jun 2011, Michael Matz wrote:

> Hi,
> 
> On Thu, 16 Jun 2011, Richard Guenther wrote:
> 
> > > If people want to not create useless conversions in the first place, 
> > > though, I suspect there are lots of places that create useless 
> > > conversions in the compiler.
> > 
> > Yeah, the above looks it comes from the frontends - gimplification 
> > should strip this conversion, if it doesn't that is a bug ;)
> 
> Well, Mike said this view_convert_expr actually is on the LHS of an 
> assignment.  I wouldn't be surprised if nobody strips "useless" 
> conversions of LHSes, exactly because such things on a LHS are no 
> conversions.

For vectors we can move them to the rhs instead.

Richard.