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From: Tom Lane <tgl@sss.pgh.pa.us>
To: Andrew Gierth <andrew@tao11.riddles.org.uk>
cc: victor@magic.io, pgsql-bugs@lists.postgresql.org
Subject: Re: BUG #15519: Casting float4 into int4 gets the wrong sign instead
 of "integer out of range" error
In-reply-to: <87zhtzqs9o.fsf@news-spur.riddles.org.uk>
References: <15519-4fc785b483201ff1@postgresql.org>
 <874lc7sb1a.fsf@news-spur.riddles.org.uk> <13162.1543014227@sss.pgh.pa.us>
 <87zhtzqs9o.fsf@news-spur.riddles.org.uk>
Comments: In-reply-to Andrew Gierth <andrew@tao11.riddles.org.uk>
	message dated "Fri, 23 Nov 2018 23:42:50 +0000"
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Andrew Gierth <andrew@tao11.riddles.org.uk> writes:
> "Tom" =3D=3D Tom Lane <tgl@sss.pgh.pa.us> writes:
>  Tom>      if (unlikely(num < (float4) INT_MIN || num >=3D (float4) INT_=
MAX || isnan(num)))

>     if (num < (float4)INT_MIN || num >=3D -(float4)INT_MIN || ...

Meh.  Seems to me that's relying on pretty much the same assumptions
and throwing in an extra dollop of obscurantism on top.

			regards, tom lane