FORTRAN compilers

Daniel Kidger Daniel.Kidger at
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

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.


(ps. yes I _do_ suspect this is actually true - I have spurious problems
with the Intel complier on xhpl too)

Dr. Dan Kidger, Quadrics Ltd.      daniel.kidger at
One Bridewell St., Bristol, BS1 2AA, UK         0117 915 5505
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