! { dg-do run } ! { dg-options "-ffrontend-optimize -fdump-tree-original" } program main implicit none real(kind=8), ALLOCATABLE :: a(:,:), b(:,:), v1(:), v2(:) real(kind=8), dimension(3,3) :: v1res, v2res integer :: n, i data v1res/ 442.d0, -492.d0, 586.d0, & -4834.d0, 5694.d0, -7066.d0, & 13042.d0, -15450.d0, 19306.d0 / data v2res/ 5522.d0, -6310.d0, 7754.d0, & -7794.d0, 8982.d0, -11034.d0, & 10490.d0, -12160.d0, 14954.d0 / n = 3 ALLOCATE(a(N,N),b(N,N),v1(N), v2(N)) a = reshape([((-1)**i*(-i-5)*(i+3)+5,i=1,n**2)], shape(a)) b = reshape([((-1)**i*(-i-1)*(i-2),i=1,n**2)], shape(a)) DO i=1,N v1 = MATMUL(a,b(:,i)) if (any(abs(v1-v1res(:,i)) > 1e-10)) call abort v2 = MATMUL(a,b(i,:)) if (any(abs(v2-v2res(:,i)) > 1e-10)) call abort ENDDO END program main ! { dg-final { scan-tree-dump-times "_gfortran_matmul" 0 "original" } }