loword on win64 message loop

[quantumfoam]

I migrated my win-api based application to lazarus 1.8.0 64-bit. (from 32 bit)
Then I noticed error on mousewheel event when converting WPARAM by LOWORD function (base.inc)

Code: Pascal  [Select][+][-]

1. function wndProc(hWnd: HWND; Msg: UINT; wParam: WPARAM; lParam: LPARAM): LRESULT; stdcall;
2. begin
3.   case Msg of
4.   ....
5.     WM_MOUSEWHEEL: begin
6.       doSomeThing( KeysToShiftState( LOWORD(wParam), .... )
7.     end;
8.   end;
9. end;

The error from Exception.Message is:
"Type procedure (parentfp_void_pointer, ANSISTRING) is not structure or union type"

Patching it to LOWORD( longint(wParam) ) seems to help, but is this the correct way?

[jamie]

most of those parameters are 64 bit now so you may need to correct for that.

 Also, why not use the already provided mouse handlers in the LCL ?
they have mouse.
 you can also define a message handler in the form class..