[Bug fortran/32393] gfortran - incorrect run time results

["burnus at gcc dot gnu dot org" <gcc-bugzilla at gcc dot gnu dot org>]

------- Comment #18 from burnus at gcc dot gnu dot org  2007-06-21 16:48 -------
> Created an attachment (id=13759)
 --> (http://gcc.gnu.org/bugzilla/attachment.cgi?id=13759&action=view) [edit]
> Warning free version
Thanks, it finally compiles with NAG "f95 -dusty", which finds directly one
problem:

Subscript 1 of IA (value 2) is out of range (1:1)
In PRMX, line 134 of test.f

I changed ia(1) to ia(20) - then it works. Actually, it works on my system
(x86_64-unknown-linux-gnu, 4.3.0 20070621) up to the option
-O3 -ffast-math -ftree-vectorize -funroll-all-loops
It also works now with ifort -O3 -xW, NAG f95, sunf95 and gfortran 4.1.0.

Interestingly, both gfortran 4.2.0 and g95 now produce (no options) for the
first matrix:
 row   1    0.0000E+00
 row   2    0.1000E+01  0.2000E+01
 row   3    0.3000E+01  0.4000E+01  0.5000E+01

g95 produces the same result as the others using "-fzero". Using NAG f95 with
-nan the program crashes with an arithmetic exception, which means that either
cc or sum in vr2 must be uninitialized when calling scprod. (-nan initializes
the variables with signalling NaN.) Thus there is still a bug lurking in the
source code.


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http://gcc.gnu.org/bugzilla/show_bug.cgi?id=32393