added virtual dtor to wxDateTimeHolidayAuthority (patch 753947)

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@21148 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

include/wx/datetime.h

@@ -1322,6 +1322,9 @@ public:
     // wxDateTimeHolidayAuthority)
     static void AddAuthority(wxDateTimeHolidayAuthority *auth);
 
+    // the base class must have a virtual dtor
+    virtual ~wxDateTimeHolidayAuthority();
+
 protected:
     // this function is called to determine whether a given day is a holiday
     virtual bool DoIsHoliday(const wxDateTime& dt) const = 0;

src/common/datetime.cpp

@@ -3863,6 +3863,11 @@ void wxDateTimeHolidayAuthority::AddAuthority(wxDateTimeHolidayAuthority *auth)
     ms_authorities.Add(auth);
 }
 
+wxDateTimeHolidayAuthority::~wxDateTimeHolidayAuthority()
+{
+    // nothing to do here
+}
+
 // ----------------------------------------------------------------------------
 // wxDateTimeWorkDays
 // ----------------------------------------------------------------------------