<table border="1" cellspacing="0" cellpadding="8">
    <tr>
        <th>Issue</th>
        <td>
            <a href=https://github.com/llvm/llvm-project/issues/68098>68098</a>
        </td>
    </tr>

    <tr>
        <th>Summary</th>
        <td>
            windows clang 17.0.1: broken template argument deduction in a constructor within a `throw` expression
        </td>
    </tr>

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

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

    <tr>
      <th>Reporter</th>
      <td>
          egor-bychin-sd
      </td>
    </tr>
</table>

<pre>
    Consider this piece of code:
```C++
class A
{
public:
    A(auto &&...args) { static_assert(sizeof...(args) == 0); }
};

int main() {
    throw A{};
}
```

It should be compiled correctly, but on Windows I get the following error:
```
PS C:\dev> clang++ -std=c++20 .\cpp.cpp
.\cpp.cpp:4:39: error: static assertion failed due to requirement 'sizeof...(args) == 0'
    4 |     A(auto &&...args) { static_assert(sizeof...(args) == 0); }
      | ^~~~~~~~~~~~~~~~~~~~
.\cpp.cpp:8:11: note: in instantiation of function template specialization 'A::A<A &>' requested here
    8 | throw A{};
      |           ^
.\cpp.cpp:4:55: note: expression evaluates to '1 == 0'
    4 |     A(auto &&...args) { static_assert(sizeof...(args) == 0); }
      | ~~~~~~~~~~~~~~~~^~~~
1 error generated.
```

This problem only happens when an instance of `A` is used in a `throw` expression.

However, on godbolt there are [no any issues](https://godbolt.org/z/dfz95dK7e), so I guess it must be something platform dependent.

Here's the version that I use:
```
PS C:\dev> clang++ --version
clang version 17.0.1
Target: x86_64-pc-windows-msvc
Thread model: posix
InstalledDir: C:\Program Files\LLVM\bin
```
</pre>
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