<table border="1" cellspacing="0" cellpadding="8">
    <tr>
        <th>Issue</th>
        <td>
            <a href=https://github.com/llvm/llvm-project/issues/75755>75755</a>
        </td>
    </tr>

    <tr>
        <th>Summary</th>
        <td>
            libc++: constexpr std::string does not work (clang 17)
        </td>
    </tr>

    <tr>
      <th>Labels</th>
      <td>
            clang,
            libc++
      </td>
    </tr>

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

    <tr>
      <th>Reporter</th>
      <td>
          q66
      </td>
    </tr>
</table>

<pre>
    The following code:

```
#include <string>

constexpr std::string foo{"XX"};

int main() {
}
```

should compile, but instead it fails with:

```
test.cc:3:23: error: constexpr variable 'foo' must be initialized by a constant expression
    3 | constexpr std::string foo{"XX"};
      | ^~~~~~~~~
test.cc:3:23: note: pointer to subobject of heap-allocated object is not a constant expression
/usr/bin/../include/c++/v1/__memory/allocator.h:112:38: note: heap allocation performed here
  112 |             return static_cast<_Tp*>(::operator new(__n * sizeof(_Tp)));
      | ^
1 error generated.
```

I haven't been able to find anything about this being broken, and available resources list the functionality as available since 15.

This is a musl/libc++/compiler-rt environment, on x86_64 architecture, but probably should not matter. The libc++ has hardened mode on.
</pre>
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