[Bug libstdc++/104945] std::hash ignores the top 32 bits when size_t is 32 bit

[pinskia at gcc dot gnu.org via Gcc-bugs]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=104945

--- Comment #1 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
Yes this is definitely an issue I think:
  // Explicit specializations for integer types.
#define _Cxx_hashtable_define_trivial_hash(_Tp)         \
  template<>                                            \
    struct hash<_Tp> : public __hash_base<size_t, _Tp>  \
    {                                                   \
      size_t                                            \
      operator()(_Tp __val) const noexcept              \
      { return static_cast<size_t>(__val); }            \
    };

....
  /// Explicit specialization for long long.
  _Cxx_hashtable_define_trivial_hash(long long)

....
  /// Explicit specialization for unsigned long long.
  _Cxx_hashtable_define_trivial_hash(unsigned long long)


With no check on size of size_t vs long long.