<table border="1" cellspacing="0" cellpadding="8">
    <tr>
        <th>Issue</th>
        <td>
            <a href=https://github.com/llvm/llvm-project/issues/54340>54340</a>
        </td>
    </tr>

    <tr>
        <th>Summary</th>
        <td>
            [Modules] Default template argument is not exported
        </td>
    </tr>

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

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

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

<pre>
    See https://godbolt.org/z/5YsKzrTGY, which GCC accepts: https://godbolt.org/z/53KnzYWob.

```C++
export module mod;
export template<class> struct X { };
export template<class T = int> using Y = X<T>;
```

```C++
import mod;
int main() {
  Y<>{};
}
```

```
test.cpp:3:3: error: default argument of 'Y' must be imported from module 'mod' before it is required
  Y<>{};
  ^
mod.cpp:3:27: note: default argument declared here is not reachable
export template<class T = int> using Y = X<T>;
                          ^
1 error generated.
```
</pre>
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