From
http://groups.google.com/group/comp.lang.fortran/browse_frm/thread/cf9a1ed1754c6f4a/ed236efb2be07bc0?tvc=1#ed236efb2be07bc0
The program
------------------------------
program tmatmul
implicit none
integer, parameter :: nmax = 3
integer :: n = 2
real, dimension(nmax,nmax) :: B=0.0, C=1.0, X=0.0
B(1,1) = 1.0
B(1,2) = 2.0
B(2,1) = 3.0
B(2,2) = 5.0
X(1:n,1) = matmul( B(2,1:n),C(1:n,1:n) )
print *, X(:,1)
print *, " Should be: 8.0 8.0 0.0"
end program tmatmul
------------------------------
produces with gfortran (4.2.0 20060612 and 4.1.0 (SUSE Linux)):
3.000000 3.000000 0.000000
Should be: 8.0 8.0 0.0
ifort, g95 and NAG f95 give the correct result (8. 8. 0.0).
--
Summary: gfortran: mathmul produces wrong result
Product: gcc
Version: unknown
Status: UNCONFIRMED
Severity: major
Priority: P3
Component: fortran
AssignedTo: unassigned at gcc dot gnu dot org
ReportedBy: tobias dot burnus at physik dot fu-berlin dot de
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=28005
