%cat source1.f
      INTEGER X(100), Y(100), I, T
C$OMP PARALLEL DO DEFAULT(__AUTO)
      DO I=1, 100
         T = Y(I)
         X(I) = T*T
      END DO
C$OMP END PARALLEL DO
      END
%f95 -xopenmp -xO3 -vpara -c -g source1.f
"source1.f", line 2: Autoscoping for OpenMP construct succeeded. 
Check er_src for details

%cat source2.f
      INTEGER X(100), Y(100), I, T
C$OMP PARALLEL DO DEFAULT(__AUTO)
      DO I=1, 100
         T = Y(I)
         CALL FOO(X)
         X(I) = T*T
      END DO
C$OMP END PARALLEL DO
      END
%f95 -xopenmp -xO3 -vpara -c -g source2.f
"source2.f", line 2: Warning: Autoscoping for OpenMP construct failed. 
 Check er-src for details. Parallel region will be executed by
 a single thread.

% er_src source2.o
Source file: source2.f
Object file: source2.o
Load Object: source2.o




     1.         INTEGER X(100), Y(100), I, T
        
   Source OpenMP region below has tag R1
   Variables autoscoped as SHARED in R1: y
   Variables autoscoped as PRIVATE in R1: t, i
   Variables treated as shared because they cannot be autoscoped in R1: x
   R1 will be executed by a single thread because autoscoping for some variable s was not successful
   Private variables in R1: i, t
   Shared variables in R1: y, x
     2. C$OMP PARALLEL DO DEFAULT(__AUTO)

   Source loop below has tag L1
   L1 parallelized by explicit user directive
   L1 autoparallelized
   L1 parallel loop-body code placed in function _$d1A2.MAIN_ along with 0 inne r loops
   L1 could not be pipelined because it contains calls
     3.         DO I=1, 100
     4.                 T = Y(I)
     5.                 CALL FOO(X)
     6.                 X(I) = T*T
     7.         END DO
     8. C$OMP END PARALLEL DO
     9.         END
    10.

 1.      REAL FUNCTION FOO (N, X, Y)
 2.      INTEGER       N, I
 3.      REAL          X(*), Y(*)
 4.      REAL          W, MM, M
 5.
 6.      W = 0.0
 7.
 8. C$OMP PARALLEL DEFAULT(__AUTO)
 9.
10. C$OMP SINGLE
11.       M = 0.0
12. C$OMP END SINGLE
13.
14.       MM = 0.0
15.
16. C$OMP DO
17.       DO I = 1, N
18.          T = X(I)
19.          Y(I) = T
20.          IF (MM .GT. T) THEN
21.             W = W + T
22.             MM = T
23.          END IF
24.       END DO
25. C$OMP END DO
26.
27. C$OMP CRITICAL
28.       IF ( MM .GT. M ) THEN
29.          M = MM
30.       END IF
31. C$OMP END CRITICAL
32.
33. C$OMP END PARALLEL
34.
35.      FOO = W - M
36.
37.      RETURN
38.      END

static void par_quick_sort (int p, int r, float *data)
{
   if (p < r) 
   {
      int q = partition (p, r, data);  
      
      #pragma omp task default(__auto) if ((r-p)>=low_limit)
      par_quick_sort (p, q-1, data);

      #pragma omp task default(__auto) if ((r-p)>=low_limit)
      par_quick_sort (q+1, r, data);
   }
}

int main ()
{
  ...
  #pragma omp parallel
  {
     #pragma omp single nowait
     par_quick_sort (0, N-1, &Data[0]);
  }
  ...
}

er_src result:

      Source OpenMP region below has tag R1
      Variables autoscoped as FIRSTPRIVATE in R1: p, q, data
      Firstprivate variables in R1: data, p, q
        47. #pragma omp task default(__auto) if ((r-p)>=low_limit)
        48. par_quick_sort (p, q-1, data);
      
      Source OpenMP region below has tag R2
      Variables autoscoped as FIRSTPRIVATE in R2: q, r, data
      Firstprivate variables in R2: data, q, r
        49. #pragma omp task default(__auto) if ((r-p)>=low_limit)
        50. par_quick_sort (q+1, r, data);

int fib (int n)
{
   int x, y;
   if (n < 2) return n;

   #pragma omp task default(__auto)
   x = fib(n - 1);

   #pragma omp task default(__auto)
   y = fib(n - 2);

   #pragma omp taskwait
   return x + y;
}

er_src result:

   Source OpenMP region below has tag R1
   Variables autoscoped as SHARED in R1: x
   Variables autoscoped as FIRSTPRIVATE in R1: n
   Shared variables in R1: x
   Firstprivate variables in R1: n
    24.         #pragma omp task default(__auto) /* shared(x) firstprivate(n) */
    25.         x = fib(n - 1);
   
   Source OpenMP region below has tag R2
   Variables autoscoped as SHARED in R2: y
   Variables autoscoped as FIRSTPRIVATE in R2: n
   Shared variables in R2: y
   Firstprivate variables in R2: n
    26.         #pragma omp task default(__auto) /* shared(y) firstprivate(n) */
    27.         y = fib(n - 2);
    28. 
    29.         #pragma omp taskwait
    30.         return x + y;
    31. }

int main(void)
{
  int yy = 0;

  #pragma omp parallel default(__auto) shared(yy)
  {
    int xx = 0;

    #pragma omp single
    {
       #pragma omp task default(__auto) // task1
       {
          xx = 20;
       }
    }

    #pragma omp task default(__auto) // task2
    {
       yy = xx;
    }
  }

  return 0;
}

er_src result:

   Source OpenMP region below has tag R1
   Variables autoscoped as PRIVATE in R1: xx
   Private variables in R1: xx
   Shared variables in R1: yy
     7.   #pragma omp parallel default(__auto) shared(yy)
     8.   {
     9.     int xx = 0;
    10.

   Source OpenMP region below has tag R2
    11.     #pragma omp single
    12.     {

   Source OpenMP region below has tag R3
   Variables autoscoped as SHARED in R3: xx
   Shared variables in R3: xx
    13.        #pragma omp task default(__auto) // task1
    14.        {
    15.           xx = 20;
    16.        }
    17.     }
    18.

   Source OpenMP region below has tag R4
   Variables autoscoped as PRIVATE in R4: yy
   Variables autoscoped as FIRSTPRIVATE in R4: xx
   Private variables in R4: yy
   Firstprivate variables in R4: xx
    19.     #pragma omp task default(__auto) // task2
    20.     {
    21.        yy = xx;
    22.     }
    23.   }

int foo(void)
{
  int xx = 1, yy = 0;

  #pragma omp parallel shared(xx,yy)
  {
    #pragma omp task default(__auto)
    {
       xx += 1;

       #pragma omp atomic
       yy += xx;
    }

    #pragma omp taskwait
  }
  return 0;
}

er_src result:

   Source OpenMP region below has tag R1
   Shared variables in R1: yy, xx
     5.   #pragma omp parallel shared(xx,yy)
     6.   {

   Source OpenMP region below has tag R2
   Variables autoscoped as SHARED in R2: yy
   Variables autoscoped as FIRSTPRIVATE in R2: xx
   Shared variables in R2: yy
   Firstprivate variables in R2: xx
     7.     #pragma omp task default(__auto)
     8.     {
     9.        xx += 1;
    10.
    11.        #pragma omp atomic
    12.        yy += xx;
    13.     }
    14.
    15.     #pragma omp taskwait
    16.   }