diff --git a/openacc/impl/psb_d_oacc_hll_csmv.F90 b/openacc/impl/psb_d_oacc_hll_csmv.F90
index bccd3d6d..d38fca61 100644
--- a/openacc/impl/psb_d_oacc_hll_csmv.F90
+++ b/openacc/impl/psb_d_oacc_hll_csmv.F90
@@ -64,11 +64,9 @@ contains
       do i = 1, m
         y(i) = beta * y(i)
       end do
-#if (__GNUC__ <= 13) 
+      ! This loop nest cannot be run with collapse, since
+      ! the inner loop extent varies.
       !$acc parallel loop present(a, x, y)
-#else      
-      !$acc parallel loop collapse(2) present(a, x, y)
-#endif
       do i = 1, nhacks
         do j = a%hkoffs(i), a%hkoffs(i + 1) - 1
           y(a%irn(j)) = y(a%irn(j)) + alpha * a%val(j) * x(a%ja(j))