<table border="1" cellspacing="0" cellpadding="8">
    <tr>
        <th>Issue</th>
        <td>
            <a href=https://github.com/llvm/llvm-project/issues/120197>120197</a>
        </td>
    </tr>

    <tr>
        <th>Summary</th>
        <td>
            Cannot compare std::string's in if constexpr
        </td>
    </tr>

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

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

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

<pre>
    This program
```c++
#include <string>

struct A {
    static constexpr std::string name() { return "a"; }  
};

template<class T>
bool f( T && ) {
    if constexpr ( T::name() == "a" )
        return true;
    else
        return false;
}

int main() {
    return f( A{} );
}
```
is accepted by GCC and MSVC, but Clang complains:
```
error: constexpr if condition is not a constant expression
    9 |     if constexpr ( T::name() == "a" )
      | ^~~~~~~~~~~~~~~~
```
Online demo: https://gcc.godbolt.org/z/o3nMx3zWj

Original discussion: https://stackoverflow.com/q/79283228/7325599

</pre>
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