<table border="1" cellspacing="0" cellpadding="8">
    <tr>
        <th>Issue</th>
        <td>
            <a href=https://github.com/llvm/llvm-project/issues/110080>110080</a>
        </td>
    </tr>

    <tr>
        <th>Summary</th>
        <td>
            clang++ outputs wrong warning for if constexpr and lambda capture combination
        </td>
    </tr>

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

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

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

<pre>
    ```cpp
struct A {
    static constexpr bool value = false;
};

struct B {
 static constexpr bool value = true;
};

void h() {}

template <class T>
struct C {
    void f() {
        auto lambda = [this] {
            if constexpr (T::value) {
                g();
 }
            else {
                h();
            }
 };
        lambda();
    }

    void g() {}
};

int main()
{
    C<A>{}.f();
 C<B>{}.f();
}
```

outputs:

```
prog.cc:14:24: warning: lambda capture 'this' is not used [-Wunused-lambda-capture]
   14 | auto lambda = [this] {
      |                        ^
prog.cc:30:12: note: in instantiation of member function 'C<A>::f' requested here
   30 | C<A>{}.f();
      |            ^
1 warning generated.
```
</pre>
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