OpenMP-Examples/sources/Example_task_dep.6.c

41 lines
737 B
C

/*
* @@name: task_depend.6.c
* @@type: C
* @@compilable: yes
* @@linkable: yes
* @@expect: success
*/
#include<stdio.h>
void foo()
{
int x = 0, y = 2;
#pragma omp task depend(inout: x) shared(x)
x++; // 1st child task
#pragma omp task shared(y)
y--; // 2nd child task
#pragma omp taskwait depend(in: x) // 1st taskwait
printf("x=%d\n",x);
// Second task may not be finished.
// Accessing y here will create a race condition.
#pragma omp taskwait // 2nd taskwait
printf("y=%d\n",y);
}
int main()
{
#pragma omp parallel
#pragma omp single
foo();
return 0;
}