General tidy-up (mainly typecasts) to allow the use of the SGI native

compilers (tested on Irix 6.5 with -mips3 -n32).


git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@623 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

src/gtk/combobox.cpp

@@ -191,7 +191,7 @@ char* wxComboBox::GetClientData( int n )
   
   wxFAIL_MSG( "wxComboBox: wrong index" );
   
-  return NULL;
+  return (char *) NULL;
 }
 
 void wxComboBox::SetClientData( int n, char * clientData )