<table border="1" cellspacing="0" cellpadding="8">
    <tr>
        <th>Issue</th>
        <td>
            <a href=https://github.com/llvm/llvm-project/issues/102157>102157</a>
        </td>
    </tr>

    <tr>
        <th>Summary</th>
        <td>
            Clang accepts invalid program when default constructor is overloaded with initializer list constructor that is also a default constructor
        </td>
    </tr>

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

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

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

<pre>
    The following [invalid](https://stackoverflow.com/questions/78836456/overloaded-default-constructor-with-initializer-list-constructor-that-is-also-a) program is accepted by clang. [Demo](https://godbolt.org/z/8nn1Pc3rz)

```
#include <initializer_list>

struct C
{ 
    C(){}
 C(std::initializer_list<int> i = {3})
    {
    }  
};

int main()
{
    C d{};   //clang:Ok, gcc:No, MSVC: No, EDG: No
}
```

This is invalid due to ambiguity between the ctors for `()` as explained in this [thread](https://stackoverflow.com/questions/78836456/overloaded-default-constructor-with-initializer-list-constructor-that-is-also-a).

Clang uses the initializer list ctor over the other default ctor which is not the correct behavior.
</pre>
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