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Cc: Steve Naroff <snaroff@apple.com>, gcc mailing list <gcc@gcc.gnu.org>,
        Matt Austern <austern@apple.com>, Michael Matz <matz@suse.de>,
        Joe Buck <Joe.Buck@synopsys.com>, Mike Stump <mrs@apple.com>
From: Andrew Pinski <pinskia@physics.uc.edu>
Subject: Re: generalized lvalues -- patch outline
Date: Mon, 22 Nov 2004 21:01:00 -0000
To: Ziemowit Laski <zlaski@apple.com>
X-SW-Source: 2004-11/txt/msg00756.txt.bz2


On Nov 22, 2004, at 3:39 PM, Ziemowit Laski wrote:

> On 19 Nov 2004, at 17.50, Ziemowit Laski wrote:
>
>> To put it another way, I'm only concerned with cases where the 
>> compiler currently complains
>> about assigning to a non-lvalue, and the non-lvalue in question is a 
>> cast of an lvalue.
>
> Indeed, I now appear to have a mainline mod for C and C++ which allows 
> assignment to lvalue casts for pointer types.  What follows is a 
> high-level synopsis of what I did; if there is interest, I can whip up 
> a full-fledged patch, complete with docs.  Please let me know.


Just use a builtin as proposed by Nathan and others for the problem you
are trying to solve.  The syntax for casts as lvalue just looks bad.
The builtin can return a reference (yes even in the C front-end you
can have references [varargs is an example of which is used as
references in the front-end]).

Thanks,
Andrew Pinski