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<base href="https://bugs.llvm.org/">
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<th>Bug ID</th>
<td><a class="bz_bug_link
bz_status_NEW "
title="NEW - Offload reduction of std::complex gives wrong result when user defined reduction is missing"
href="https://bugs.llvm.org/show_bug.cgi?id=46146">46146</a>
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<th>Summary</th>
<td>Offload reduction of std::complex gives wrong result when user defined reduction is missing
</td>
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<th>Product</th>
<td>OpenMP
</td>
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<th>Version</th>
<td>unspecified
</td>
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<th>Hardware</th>
<td>PC
</td>
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<th>OS</th>
<td>Linux
</td>
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<th>Status</th>
<td>NEW
</td>
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<th>Severity</th>
<td>enhancement
</td>
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<th>Priority</th>
<td>P
</td>
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<th>Component</th>
<td>Clang Compiler Support
</td>
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<th>Assignee</th>
<td>unassignedclangbugs@nondot.org
</td>
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<th>Reporter</th>
<td>xw111luoye@gmail.com
</td>
</tr>
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<th>CC</th>
<td>llvm-bugs@lists.llvm.org
</td>
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<p>
<div>
<pre><a href="https://github.com/ye-luo/openmp-target/blob/master/hands-on/tests/complex/complex_reduction.cpp">https://github.com/ye-luo/openmp-target/blob/master/hands-on/tests/complex/complex_reduction.cpp</a>
On CPU with and without user defined reduction (UDR) always work.
$ clang++ -fopenmp ./complex_reduction.cpp
$ clang++ -fopenmp -D__NO_UDR ./complex_reduction.cpp
On GPU, the code works with UDR.
$ clang++ -fopenmp -fopenmp-targets=nvptx64 ./complex_reduction.cpp
with outUDR, it gives wrong result.
$ clang++ -fopenmp -fopenmp-targets=nvptx64 -D__NO_UDR ./complex_reduction.cpp
$ ./a.out
wrong reduction value check(0,0) correct value (4950,-4950)
wrong reduction value check(-3.42281e-49,7.67314e-308) correct value
(4950,-4950)
This is not expected. The code should either not compile and ask UDR or works
with correct numbers without UDR just like the CPU case.</pre>
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