segfault when extracting symbol which inherits from std::filesystem::path provided by libstdc++

[mizvekov]

This example was extracted from the pipeline crash in https://github.com/cppalliance/mrdocs/actions/runs/19977506493/job/57299356491?pr=1077

Happens when testing the fmt library example, when using the system libstdc++.

#include <filesystem>
namespace fmt {
  class path : public std::filesystem::path {};
}

[mizvekov]

Reduced to:

namespace std {
  class path {
    struct _Cmpt;
  };
  struct path::_Cmpt : path {};
} // namespace std
namespace fmt {
  class path : public std::path {};
} // namespace fmt