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From: Eric Botcazou <ebotcazou@libertysurf.fr>
To: Hiroshi Fujishima <hiroshi.fujishima@gmail.com>
Subject: Re: isinf
Date: Wed, 13 Jul 2005 19:08:00 -0000
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> Why does the compilation of b.c fail, while that of a.c succeeds with
> gcc-4.0.0 or later?

Because the call to isinf is optimized away even at -O0 in the latter case 
(isinf being a pure function), but not in the former.  That could be deemed 
a little questionable though.  The gap is eliminated at -O1.

-- 
Eric Botcazou