Local Data in Pure Subroutines

[mattsdad]

Will the local data inFortran's pure subroutines ever "cross wires" due to parallel read-modify-write in different threads?

[Steven_L_Intel1]

If you're using /parallel or OpenMP that is coded properly, there should not be a problem. Pure routines really aren't anything special in this regard.

[mattsdad]

Yes, I have an OMP PARALLEL DO loop. The loop index is used to specify a different element of an array. Only that specific element is passed into the pure subroutine. So all the affected data from outside the pure subroutine is preperly segreated by thread.

The real question is - does the locally declared data in the called subroutine need to have OMP directives to prevent interaction between threads?

[Steven_L_Intel1]

By default,. all variables are "automatic" (stack allocated) when OpenMP is used. So unless you did something that woild force static allocation (SAVE or initialization), nothing should need to be done.

[mattsdad]

Does the POINTER attribute cause a variable to be STATIC when there is no initialization?

[Steven_L_Intel1]

No.

[mattsdad]

Does theTARGET attribute cause a variable to be STATIC when there is no initialization?

[Steven_L_Intel1]

No. The only thing that forces static allocation for local variables is the SAVE attribute, either explicit or implicit. The only way you get SAVE implicitly is with initialization.