<table border="1" cellspacing="0" cellpadding="8">
<tr>
<th>Issue</th>
<td>
<a href=https://github.com/llvm/llvm-project/issues/64694>64694</a>
</td>
</tr>
<tr>
<th>Summary</th>
<td>
OpenMP atomic operation does not work properly on Windows with clang
</td>
</tr>
<tr>
<th>Labels</th>
<td>
new issue
</td>
</tr>
<tr>
<th>Assignees</th>
<td>
</td>
</tr>
<tr>
<th>Reporter</th>
<td>
annop-w
</td>
</tr>
</table>
<pre>
The following program produces wrong result with -O3
```
#include <iostream>
#include <omp.h>
int main () {
double sum = 0.0;
int i;
#pragma omp parallel for default(none) private(i) shared(sum)
for (i = 0; i < 1000; ++i) {
#pragma omp atomic
sum += 1.0;
}
std::cout << sum << std::endl;
return 0;
}
```
```
clang version 16.0.0
Target: aarch64-pc-windows-msvc
Thread model: posix
```
</pre>
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