Odd MSYS2-64 "feature" havin issues here using SetWindowLongx with index GWLP_WNDPROC on 64bit ...
(other indices do fine. GWLP_WNDPROC even with 32bit).-> reinstalled MSYS2 from scratch didnt do it, so
decided to try VS15. -> Result: everything does fine now even on 64Bit.
->...but now : i need a vacation.
PS; MSYS2 isnt normally that bad.. i will continue to use it. but that bug is really nasty.
To reproduce: Install MSYS2 /do: pacman Syu /do: pacman -S mingw-w64-x86_64-toolchain.