0 Replies Latest reply on Jun 3, 2011 12:42 PM by allen@radiative.com

    Segmentation fault in FORTRAN OpenMP loop

    allen@radiative.com

      Hi: I've been experimenting building our modestly large FORTRAN program with OpenF95 4.2.5.1. When I build with OpenMP and -O3, I get a segmentation fault in a parallelized loop. The parallelized loop is relatively straight-forward, but it is nested and it references an array element of an array of user-defined types, which itself contains an array. Also, there is yet another interior implicit loop over the leading dimension of these arrays.

      do i = 1, n
         do j = i, m
           !$omp parallel do
          do k = 1, o
            do l = 1, p
               A(:,l,k) = A(:,l,k)  + B(:,l,k) * C(j)%D(:,l,k)
            end do
         end do
        !$omp end parallel do
        end do
      end do

      I abstracted this bit of code into a separate program and compiled it, but I cannot reproduce the segmentation fault. Could you give me some suggestions on how to reduce my code to something which I can post?

      Thanks,
      Allen