How to resolve omp_get_wtime undefined in c?-CodePudding

I know this has been asked before but if you look at the causes of the issues that prompted previous users to ask the same question , they were different and this this issue could have multiple causes , that is why am asking again. I have a program in c with omp, I am trying to measure the execution time for a loop to add numbers except that am getting an error that the reference the function omp_get_wtime() is undefined while I have the library file included in the header section of my code file...

Why am i getting this error and how can I resolve it?

#include <omp.h>
#include <stdlib.h>
#include <string.h>

int main(){
//number of threads to use
int no_threads=3;
//mark the execution go mark
double start=omp_get_wtime();
//parallelize the loop
#pragma omp parallel num_threads(no_threads)
for(int i=0;i<1000;i  ){
  printf("%d",i);
 }
double end_time=omp_get_wtime();
printf("%f",end_time-start);

}

I tried to compile even before I started using the #pragma directive and got the error that the omp function is undefined and the function in the file. Please help me resolve this.

CodePudding user response：

You should build an OMP program with a flag.

gcc -fopenmp test.c