# GAP Message (Diagnostic ID 30528)

### Note

This feature is only available for ifort.

## Message

Add "%s" to the declaration of routine "%s" in order to parallelize the loop at line %d. Adding "%s" achieves a similar effect.

## Advice

Confirm that the routine specified is indeed an elemental function or an ATTRIBUTES CONCURRENCY_SAFE function before following the advice to add the annotation.

If the routine is not one of these kinds of functions, try to inline it with a FORCEINLINE RECURSIVE directive. This action may or may not be beneficial.

## Example

Consider the following:

          subroutine foo ()
          integer, parameter :: N2 = 10000
          real (8) :: A(N2), B(N2)
          interface
             function bar (k)
             integer :: bar, k
             end function bar
          end interface

          integer :: i
          do i =1, N2
             A(i) = B(i) * bar(N2)
          end do
          end subroutine foo

In this case, to parallelize the loop at line 11, declare the routine `bar` as elemental.

If you determine it is safe to do so, an alternative way you can modify the program code is as follows:

          subroutine foo ()
          integer, parameter :: N2 = 10000
          real (8) :: A(N2), B(N2)
          interface
             function bar (k)
          !dir$ attributes concurrency_safe : profitable
             integer :: bar, k
             end function bar
          end interface

          integer :: i
          do i =1, N2
             A(i) = B(i) * bar(N2)
          end do
          end subroutine foo

## Verify

Confirm that the routine satisfies the semantics of this declaration. Another way to help the loop being parallelized is to inline the routine with the FORCEINLINE RECURSIVE directive, but this method does not guarantee parallelization.

Parent topic: Guided Auto Parallelism Messages

## See Also

GAP Message (Diagnostic ID 30526)