> in uae_types.h:
>
> |#if defined(__x86_64__) && defined(HAS_uae_64)
>    typedef uae_u64 uaecptr;
> # else
>    typedef uae_u32 uaecptr;
> # endif // __x86_64__
> |
>
> looks to me like it can be both 32 and 64 bits

This makes no sense. There is no 64-bit M680x0 CPU or Amiga hardware.