diff --git a/dlls/atl/atlbase.h b/dlls/atl/atlbase.h
index ad7acfac835..49c13e439a3 100644
--- a/dlls/atl/atlbase.h
+++ b/dlls/atl/atlbase.h
@@ -28,9 +28,9 @@
 typedef HRESULT (WINAPI _ATL_CREATORFUNC)(void* pv, REFIID riid, LPVOID* ppv);
 typedef HRESULT (WINAPI _ATL_CREATORARGFUNC)(void* pv, REFIID riid, LPVOID* ppv, DWORD dw);
 typedef HRESULT (WINAPI _ATL_MODULEFUNC)(DWORD dw);
-typedef LPCSTR (WINAPI _ATL_DESCRIPTIONFUNCA)();
-typedef LPCWSTR (WINAPI _ATL_DESCRIPTIONFUNCW)();
-typedef const struct _ATL_CATMAP_ENTRY* (_ATL_CATMAPFUNC)();
+typedef LPCSTR (WINAPI _ATL_DESCRIPTIONFUNCA)(void);
+typedef LPCWSTR (WINAPI _ATL_DESCRIPTIONFUNCW)(void);
+typedef const struct _ATL_CATMAP_ENTRY* (_ATL_CATMAPFUNC)(void);
 typedef void (WINAPI _ATL_TERMFUNC)(DWORD dw);
 
 typedef struct _ATL_OBJMAP_ENTRYA_TAG