<table border="1" cellspacing="0" cellpadding="8">
    <tr>
        <th>Issue</th>
        <td>
            <a href=https://github.com/llvm/llvm-project/issues/112884>112884</a>
        </td>
    </tr>

    <tr>
        <th>Summary</th>
        <td>
            [flang][OpenMP] crash in OpenMPIRBuilder when trying to outline a parallel region with an infinite loop
        </td>
    </tr>

    <tr>
      <th>Labels</th>
      <td>
            crash-on-valid,
            flang:openmp,
            llvm:openmpirbuilder
      </td>
    </tr>

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

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

<pre>
    ```
program infinite_loop
  integer :: i
  !$omp parallel
  do
    i = 0
 end do
  !$omp end parallel
end program
```

This crashes in `llvm::CodeExtractor::findAllocas` called from `llvm::OpenMPIRBuilder::createParallel`. My guess is that the code extractor is looking for live out-values from the CFG region but gets stuck at the infinite loop.

Surprisingly equivalent C code does not crash clang.

Reproduce with `flang -fopenmp file.f90`
</pre>
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