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Message-ID:	<487E3A3A.3060909@iki.fi>
Date:	Wed, 16 Jul 2008 21:13:14 +0300
From:	Andris Pavenis <andris DOT pavenis AT iki DOT fi>
User-Agent:	Thunderbird 2.0.0.14 (X11/20080501)
MIME-Version:	1.0
To:	djgpp-workers AT delorie DOT com
Subject:	Re: Fixes for strict aliasing warnings from GCC-4.3.1
References:	<487E2DD0 DOT 7080400 AT iki DOT fi> <200807161743 DOT m6GHhgeF026876 AT envy DOT delorie DOT com>
In-Reply-To:	<200807161743.m6GHhgeF026876@envy.delorie.com>
Reply-To:	djgpp-workers AT delorie DOT com

DJ Delorie wrote:
> We have a union-based trick we use for UNCONST, maybe that would be
> cleaner to use than all those casts anyway?
> 
> As a bonus, it would avoid the aliasing problems the "right way".
> 
> #define unconst(__v, __t) __extension__ ({union { const __t __cp; __t __p; } __q; __q.__cp = __v; __q.__p;})
> 
> We could define a "as_long" that unions typeof(x) with long.

I know.

One can however use this typedef in macros like ones from include/ieeefp.h. It is not so nice
with union trick. That is reason why I choosed this way.

Andris

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