<table border="1" cellspacing="0" cellpadding="8">
    <tr>
        <th>Issue</th>
        <td>
            <a href=https://github.com/llvm/llvm-project/issues/86643>86643</a>
        </td>
    </tr>

    <tr>
        <th>Summary</th>
        <td>
            Inconsistent application of base class copy elision
        </td>
    </tr>

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

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

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

<pre>
    In this program:
```
#include <iostream>

struct A {};

struct B {
  B() { std::cout << "B "; } 
  B(B&&) { std::cout << "Bmove "; } 
};

struct C : A, B {};

int main() {
    [[maybe_unused]] C x{ {},  {} };
 std::cout << "\n---\n";
    [[maybe_unused]] C y{ {}, B{} };
}
```
both GCC and MSVC print
```
B 
---
B 
```
So they perform base class copy elision (which I known is questionable).

And Clang prints:
```
B 
---
B Bmove 
```
Online demo: https://gcc.godbolt.org/z/dozGhv5q7

Why copy elision is applied in one case but not in the other? Could you please explain this inconsistency?
</pre>
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