<table border="1" cellspacing="0" cellpadding="8">
    <tr>
        <th>Issue</th>
        <td>
            <a href=https://github.com/llvm/llvm-project/issues/65249>65249</a>
        </td>
    </tr>

    <tr>
        <th>Summary</th>
        <td>
            Clang produces wrong code for loading an atomic inside a struct
        </td>
    </tr>

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

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

    <tr>
      <th>Reporter</th>
      <td>
          sunmy2019
      </td>
    </tr>
</table>

<pre>
    The following `foo` was optimized to noop.


```c++
#include <atomic>

struct {
    std::atomic<double> a;
} a;

double foo() {
    return a.a;
}
```


https://godbolt.org/z/84MjG7jxa

clang 16 and trunk

The original LLVM output from clang seems OK. It was wrongly optimized during the LLVM passes.
</pre>
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