Error in example A.13.4f of OpenMP 3.0 spec

[nathanweeks]

There is an error in example A.13.4f (p. 182, line 32) of the OpenMP 3.0 spec:

Code: Select all

!$OMP END TASKWAIT


should be

Code: Select all

!$OMP TASKWAIT


Regarding the Fortran code itself, gfortran 4.4.0 issues the following error when attempting to compile the recursive function as part of a simple program:

Code: Select all

             i = fib( n-1 )
                    1
Error: 'fib' at (1) is the name of a recursive function and so refers to the result variable. Use an explicit RESULT variable for direct recursion (12.5.2.1)


Sun Studio Express 3/09 issues a warning containing a similar message when invoked with "-ansi".

A more portable version of example A.13.4f:

Code: Select all

     
      RECURSIVE INTEGER FUNCTION fib(n) RESULT(res)
      INTEGER n, i, j
      IF ( n .LT. 2) THEN
        res = n
      ELSE
!$OMP TASK SHARED(i)
        i = fib( n-1 )
!$OMP END TASK
!$OMP TASK SHARED(j)
        j = fib( n-2 )
!$OMP END TASK
!$OMP TASKWAIT
        res = i+j
      END IF
      END FUNCTION


--
Nathan Weeks

[kli]

Yes, there is a typo in the example A.13.4f. "END TASKWAIT" should be "TASKWAIT". In addition, as suggested, the example should be changed to be standard conformance that requires RESULT in the function definition.

We will track these two issues and update the specification in the next revision.

Thanks.

Kelvin Li on behalf of OpenMP ARB