<table border="1" cellspacing="0" cellpadding="8">
    <tr>
        <th>Issue</th>
        <td>
            <a href=https://github.com/llvm/llvm-project/issues/131080>131080</a>
        </td>
    </tr>

    <tr>
        <th>Summary</th>
        <td>
            `if constexpr` appears to not work correctly in some nested templates
        </td>
    </tr>

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

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

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

<pre>
    I think I've seen similar tickets at some point, so this could be a duplicate.

The following code doesn't compile, but it should: https://gcc.godbolt.org/z/648eY8eh5

```cpp
template <typename T>
struct FalsePredicate
{
    static constexpr bool value = false;
};

template <typename T, template <typename> typename Cond>
void foo()
{
    []<template <typename> typename Cond2 = Cond>
    {
 if constexpr (Cond2<T>::value)
            T::foo();
    }();
}

int main()
{
    foo<int, FalsePredicate>();
}
```

It says that `T::foo()` is invalid for `T=int`, despite there being `if constexpr`.

Tested on Clang 20 and trunk.
</pre>
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