Don't define GWL_USERDATA, GWL_ID, GWL_HWNDPARENT, GWL_HINSTANCE and
GWL_WNDPROC when compiling the Wine source.
diff --git a/include/winuser.h b/include/winuser.h
index 7490c64..1585f2a 100644
--- a/include/winuser.h
+++ b/include/winuser.h
@@ -1344,13 +1344,15 @@
#define WC_DIALOG WINELIB_NAME_AW(WC_DIALOG)
/* Offsets for GetWindowLong() and GetWindowWord() */
-#define GWL_USERDATA (-21)
#define GWL_EXSTYLE (-20)
#define GWL_STYLE (-16)
-#define GWL_ID (-12)
-#define GWL_HWNDPARENT (-8)
-#define GWL_HINSTANCE (-6)
-#define GWL_WNDPROC (-4)
+#ifndef __WINESRC__
+# define GWL_USERDATA (-21)
+# define GWL_ID (-12)
+# define GWL_HWNDPARENT (-8)
+# define GWL_HINSTANCE (-6)
+# define GWL_WNDPROC (-4)
+#endif /* __WINESRC__ */
#define DWL_MSGRESULT 0
#define DWL_DLGPROC 4
#define DWL_USER 8
