error: invalid type for iteration variable ‘i’ #pragma omp parallel for
#include <stdio.h>
#include <omp.h>
int main() {
int i;
#pragma omp parallel for
for (i = 0; i < 10; i++) {
printf("%d\n", i);
}
return 0;
}
The error invalid type for iteration variable 'i'
occurs in this OpenMP code due to missing OpenMP directives. When using OpenMP directives, the iteration variable in a for
loop needs to be a signed integer type. In this case, the variable i
should be declared as signed int i
or int i
to resolve the error.