[Bug libstdc++/102825] New: std::move_only_function's implementation breaking existing code

[hewillk at gmail dot com via Gcc-bugs]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=102825

            Bug ID: 102825
           Summary: std::move_only_function's implementation breaking
                    existing code
           Product: gcc
           Version: 12.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: libstdc++
          Assignee: unassigned at gcc dot gnu.org
          Reporter: hewillk at gmail dot com
  Target Milestone: ---

mofunc_impl.h#L111:

  : _Mofunc_base(nullptr), _M_invoke(&_S_invoke<_Tp>)

_Mofunc_basede does not have a constructor which accepts a nullptr.

#include <functional>
https://godbolt.org/z/59T4obz4j