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Re: What is acceptable for -ffast-math?
- To: gcc at gcc dot gnu dot org
- Subject: Re: What is acceptable for -ffast-math?
- From: kaih at khms dot westfalen dot de (Kai Henningsen)
- Date: 03 Aug 2001 19:41:00 +0200
- Comment: Unsolicited commercial mail will incur an US$100 handling fee per received mail.
- Organization: Organisation? Me?! Are you kidding?
- References: <20010801171343.5E207F2B65@nile.gnat.com>
firstname.lastname@example.org wrote on 01.08.01 in <20010801171343.5E207F2B65@nile.gnat.com>:
> a/2.0/2.0 will never yield zero if a is non-zero
> a/4.0 may indeed yield zero if a is the smallest number
If a is the smallest positive number in some floating point type, then I
would certainly expect both a/2.0 and a/4.0 do the same thing - either
yield zero or signal underflow.
And I certainly do not see how a second /2.0 can possibly change that.
> Indeed if one saw a/2.0/2.0 that's pretty peculiar, and it would not be
> unreasonable to guess that the properly of not yielding zero was being
> exploited :-)
What buggy idea of floating point does this?!