diff --git a/include/wx/generic/choicdgg.h b/include/wx/generic/choicdgg.h
index 4abb598a53..99b2367741 100644
--- a/include/wx/generic/choicdgg.h
+++ b/include/wx/generic/choicdgg.h
@@ -9,8 +9,8 @@
 // Licence:     wxWindows licence
 /////////////////////////////////////////////////////////////////////////////
 
-#ifndef __CHOICEDLGH_G__
-#define __CHOICEDLGH_G__
+#ifndef _WX_GENERIC_CHOICDGG_H_
+#define _WX_GENERIC_CHOICDGG_H_
 
 #include "wx/dynarray.h"
 #include "wx/dialog.h"
@@ -230,7 +230,7 @@ private:
 WXDLLEXPORT wxString wxGetSingleChoice(const wxString& message,
                                        const wxString& caption,
                                        const wxArrayString& choices,
-                                       wxWindow *parent = (wxWindow *) NULL,
+                                       wxWindow *parent = NULL,
                                        int x = wxDefaultCoord,
                                        int y = wxDefaultCoord,
                                        bool centre = true,
@@ -240,7 +240,7 @@ WXDLLEXPORT wxString wxGetSingleChoice(const wxString& message,
 WXDLLEXPORT wxString wxGetSingleChoice(const wxString& message,
                                        const wxString& caption,
                                        int n, const wxString *choices,
-                                       wxWindow *parent = (wxWindow *) NULL,
+                                       wxWindow *parent = NULL,
                                        int x = wxDefaultCoord,
                                        int y = wxDefaultCoord,
                                        bool centre = true,
@@ -252,7 +252,7 @@ WXDLLEXPORT wxString wxGetSingleChoice(const wxString& message,
 WXDLLEXPORT int wxGetSingleChoiceIndex(const wxString& message,
                                        const wxString& caption,
                                        const wxArrayString& choices,
-                                       wxWindow *parent = (wxWindow *) NULL,
+                                       wxWindow *parent = NULL,
                                        int x = wxDefaultCoord,
                                        int y = wxDefaultCoord,
                                        bool centre = true,
@@ -262,7 +262,7 @@ WXDLLEXPORT int wxGetSingleChoiceIndex(const wxString& message,
 WXDLLEXPORT int wxGetSingleChoiceIndex(const wxString& message,
                                        const wxString& caption,
                                        int n, const wxString *choices,
-                                       wxWindow *parent = (wxWindow *) NULL,
+                                       wxWindow *parent = NULL,
                                        int x = wxDefaultCoord,
                                        int y = wxDefaultCoord,
                                        bool centre = true,
@@ -274,7 +274,7 @@ WXDLLEXPORT void* wxGetSingleChoiceData(const wxString& message,
                                         const wxString& caption,
                                         const wxArrayString& choices,
                                         void **client_data,
-                                        wxWindow *parent = (wxWindow *) NULL,
+                                        wxWindow *parent = NULL,
                                         int x = wxDefaultCoord,
                                         int y = wxDefaultCoord,
                                         bool centre = true,
@@ -285,7 +285,7 @@ WXDLLEXPORT void* wxGetSingleChoiceData(const wxString& message,
                                         const wxString& caption,
                                         int n, const wxString *choices,
                                         void **client_data,
-                                        wxWindow *parent = (wxWindow *) NULL,
+                                        wxWindow *parent = NULL,
                                         int x = wxDefaultCoord,
                                         int y = wxDefaultCoord,
                                         bool centre = true,
@@ -299,7 +299,7 @@ WXDLLEXPORT size_t wxGetMultipleChoices(wxArrayInt& selections,
                                         const wxString& message,
                                         const wxString& caption,
                                         int n, const wxString *choices,
-                                        wxWindow *parent = (wxWindow *) NULL,
+                                        wxWindow *parent = NULL,
                                         int x = wxDefaultCoord,
                                         int y = wxDefaultCoord,
                                         bool centre = true,
@@ -310,11 +310,11 @@ WXDLLEXPORT size_t wxGetMultipleChoices(wxArrayInt& selections,
                                         const wxString& message,
                                         const wxString& caption,
                                         const wxArrayString& choices,
-                                        wxWindow *parent = (wxWindow *) NULL,
+                                        wxWindow *parent = NULL,
                                         int x = wxDefaultCoord,
                                         int y = wxDefaultCoord,
                                         bool centre = true,
                                         int width = wxCHOICE_WIDTH,
                                         int height = wxCHOICE_HEIGHT);
 
-#endif // __CHOICEDLGH_G__
+#endif // _WX_GENERIC_CHOICDGG_H_