DRB059-lastprivate-orig-no.c

/*
Copyright (c) 2017, Lawrence Livermore National Security, LLC.
Produced at the Lawrence Livermore National Laboratory
Written by Chunhua Liao, Pei-Hung Lin, Joshua Asplund,
Markus Schordan, and Ian Karlin
(email: liao6@llnl.gov, lin32@llnl.gov, asplund1@llnl.gov,
schordan1@llnl.gov, karlin1@llnl.gov)
LLNL-CODE-732144
All rights reserved.

This file is part of DataRaceBench. For details, see
https://github.com/LLNL/dataracebench. Please also see the LICENSE file
for our additional BSD notice.

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*/

/*
Using lastprivate() to resolve an output dependence.

Semantics of lastprivate (x):
causes the corresponding original list item to be updated after the end of the region.
The compiler/runtime copies the local value back to the shared one within the last iteration.
*/
#include <stdio.h>

void foo()
{
  int i,x;
#pragma omp parallel for private (i) lastprivate (x)
  for (i=0;i<100;i++)
    x=i;
  printf("x=%d",x);
}

int main()
{
  foo();
  return 0;
}