<table border="1" cellspacing="0" cellpadding="8">
    <tr>
        <th>Issue</th>
        <td>
            <a href=https://github.com/llvm/llvm-project/issues/76121>76121</a>
        </td>
    </tr>

    <tr>
        <th>Summary</th>
        <td>
            [OpenMP] [Flang] Program crashes at runtime with Segmentation fault when OMP PARALLEL DO IF(.false.) is encountered
        </td>
    </tr>

    <tr>
      <th>Labels</th>
      <td>
            flang
      </td>
    </tr>

    <tr>
      <th>Assignees</th>
      <td>
            chandankds
      </td>
    </tr>

    <tr>
      <th>Reporter</th>
      <td>
          chandankds
      </td>
    </tr>
</table>

<pre>
    Testcase to reproduce the issue.

```
PROGRAM parallel_do_if
  USE OMP_LIB
  INTEGER :: I
  INTEGER :: N = 0
  INTEGER, PARAMETER :: NI = 10
!$OMP PARALLEL DO IF(.false.) 
  DO I = 1, NI
  END DO
!$OMP END PARALLEL DO
END PROGRAM
```
compile: flang-new -fopenmp ./test.f90 -o if.out
Run: ./if.out

Analysis: Segmentation fault is caused by null pointer dereference inside the __kmpc_fork_call_if function.

Triage: Issue introduced after https://github.com/llvm/llvm-project/pull/65436 . Testcase works as expected after removal of this patch.

Proposed Fix: Replace nullptr with struct of pointers to shared variables that aren't global

</pre>
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