<table border="1" cellspacing="0" cellpadding="8">
    <tr>
        <th>Issue</th>
        <td>
            <a href=https://github.com/llvm/llvm-project/issues/67172>67172</a>
        </td>
    </tr>

    <tr>
        <th>Summary</th>
        <td>
            Clang fails to deduce parameter pack for a function pointer's arguments if there are arguments after the pack
        </td>
    </tr>

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

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

    <tr>
      <th>Reporter</th>
      <td>
          jeremy-rifkin
      </td>
    </tr>
</table>

<pre>
    Clang fails to compile the following code

```cpp
int foo(int, float, void*);

template<typename R, typename... Args>
R wrap(R(*fun)(Args..., void*), Args&&... args) {
    return fun(std::forward<Args>(args)..., nullptr);
}

void bar() {
 wrap(foo, 1, 2.2f);
}
```

```
<source>:11:5: error: no matching function for call to 'wrap'
   11 |     wrap(foo, 1, 2.2f);
 |     ^~~~
<source>:6:3: note: candidate template ignored: could not match 'void *' against 'int'
    6 | R wrap(R(*fun)(Args..., void*), Args&&... args) {
      |   ^
1 error generated.
```

This is ostensibly valid code. `Args...` in the declaration of fun should be a non-deduced context and the arguments should be deduced correctly as far as I can tell https://eel.is/c++draft/temp.deduct.type#5.7.

https://godbolt.org/z/sjnbTzW3b

GCC and MSVC also fail to compile this. There is an issue for GCC here https://gcc.gnu.org/bugzilla/show_bug.cgi?id=56190.

Clang successfully compiles this code if given `R`
```cpp
void bar() {
 wrap<int>(foo, 1, 2.2f);
}
```

There is 100% buggy behavior somewhere here.

https://godbolt.org/z/v7n8cYrKe
</pre>
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