diff --git a/include/wx/osx/core/private/strconv_cf.h b/include/wx/osx/core/private/strconv_cf.h
index 1c49cc3919..a295528576 100644
--- a/include/wx/osx/core/private/strconv_cf.h
+++ b/include/wx/osx/core/private/strconv_cf.h
@@ -295,7 +295,7 @@ public:
         Init(CFStringGetSystemEncoding()) ;
     }
 
-    wxMBConv_cf(const wxMBConv_cf& conv)
+    wxMBConv_cf(const wxMBConv_cf& conv) : wxMBConv()
     {
         m_encoding = conv.m_encoding;
     }
diff --git a/include/wx/valnum.h b/include/wx/valnum.h
index 19320248e4..2fbfe607b8 100644
--- a/include/wx/valnum.h
+++ b/include/wx/valnum.h
@@ -49,7 +49,7 @@ protected:
         m_style = style;
     }
 
-    wxNumValidatorBase(const wxNumValidatorBase& other)
+    wxNumValidatorBase(const wxNumValidatorBase& other) : wxValidator()
     {
         m_style = other.m_style;
     }