<table border="1" cellspacing="0" cellpadding="8">
    <tr>
        <th>Issue</th>
        <td>
            <a href=https://github.com/llvm/llvm-project/issues/122260>122260</a>
        </td>
    </tr>

    <tr>
        <th>Summary</th>
        <td>
            OpenMP offloaded code crashes at compilation/runtime depending on optimization flags
        </td>
    </tr>

    <tr>
      <th>Labels</th>
      <td>
            new issue
      </td>
    </tr>

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

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

<pre>
    I'm trying to compile the stencil3d-omp benchmark of HeCBench: [https://github.com/zjin-lcf/HeCBench/blob/master/src/stencil3d-omp/main.cpp](https://github.com/zjin-lcf/HeCBench/blob/master/src/stencil3d-omp/main.cpp)

I'm using LLVM version 19.1.3 on a MI100 AMD GPU. 

If I compile the code with -O3 everything works and the results match with the ones from SYCL and HIP:
`make CC=clang++ CFLAGS="-fopenmp -fopenmp-targets=amdgcn-amd-amdhsa -Xopenmp-target=amdgcn-amd-amdhsa -march=gfx908"`

If I compile the code without any optimization flags the compilation is successful, however at runtime i get the following error: 
`AMDGPU fatal error 1: Memory access fault by GPU 8 (agent 0x55f222c19fb0) at virtual address 0x7f8c9c06a000. Reasons: Page not present or supervisor privilege
Aborted (core dumped)
`
Lastly, if I compile the code with O0, O1 or O2 I get a Segfault at compilation: [O0_compilation_output.txt](https://github.com/user-attachments/files/18361060/O0_compilation_output.txt)

The only difference I was able to find between the O0 and O3 version is that the O0 version launches the OpenMP kernels in generic mode and the O3 in generic-SPMD mode. Could this be the reason for the crash?

</pre>
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