FORTRAN compilers
Daniel Kidger
Daniel.Kidger at quadrics.com
Fri Nov 23 10:15:30 PST 2001
>Right : compilation and test of LINPACK on our system
>gives at least 50% failure of precision tests with pgf77,
>versus 0% with g77. However, when it works, the
>generated code is at least 20% faster than with
>other compilers.
That does not prove that pgf77 is broken!
What if linpack (./xhpl) has a bug whereby a variable is not initialised to
zero?
pgf77 may be actingly correctly by not having to initialise it and g77 may
be over-keen in setting all undeclared values to be zero.
Yours,
Daniel.
(ps. yes I _do_ suspect this is actually true - I have spurious problems
with the Intel complier on xhpl too)
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Dr. Dan Kidger, Quadrics Ltd. daniel.kidger at quadrics.com
One Bridewell St., Bristol, BS1 2AA, UK 0117 915 5505
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