diff --git a/rtl/win/wininc/base.inc b/rtl/win/wininc/base.inc
index a78d5e0eb1..e03419feeb 100644
--- a/rtl/win/wininc/base.inc
+++ b/rtl/win/wininc/base.inc
@@ -137,7 +137,7 @@
      LANGID = word;
      LCID   = DWORD;
      LCTYPE = DWORD;
-     LPARAM = LONG_PTR;
+     LPARAM = ptruint;
 
      LP     = ^word;
      LPBOOL = ^WINBOOL;