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Re: g77 -ieee crash in 1.0.3a
- To: Dave Love <d dot love at dl dot ac dot uk>, Craig Burley <burley at gnu dot org>
- Subject: Re: g77 -ieee crash in 1.0.3a
- From: Greg Lindahl <lindahl at cs dot virginia dot edu>
- Date: Thu, 30 Jul 1998 09:21:14 -0400 (EDT)
- Cc: lindahl at cs dot virginia dot edu, egcs-patches at cygnus dot com, toon at moene dot indiv dot nluug dot nl
> BTW, I don't understand the reason for -mieee with LAPACK (was it?) in
> the first place.
-mieee is never supposed to crash the compiler. This kind of crash is
the kind that would get diagnosed by the "compile a few million lines
of code just to see what happens" test Craig and I and others have
been contemplating.
If you want to know why I threw it: a user got an fp exception, and I
told them "try -mieee and see if that fixes it." It's standard
debugging procedure on an Alpha. In fact, one of the legit biggest
uses of denorms is in matrix algebra in ill-conditioned systems.
Gradual underflow is your friend in that situation.
-- g