diff --git a/Source/cmGlobalGenerator.h b/Source/cmGlobalGenerator.h
index aa2dd2291b..cc7ffed989 100644
--- a/Source/cmGlobalGenerator.h
+++ b/Source/cmGlobalGenerator.h
@@ -560,12 +560,6 @@ private:
       : LastDiskTime(-1)
     {
     }
-    DirectoryContent(DirectoryContent const& dc)
-      : LastDiskTime(dc.LastDiskTime)
-      , All(dc.All)
-      , Generated(dc.Generated)
-    {
-    }
   };
   std::map<std::string, DirectoryContent> DirectoryContentMap;