--- old/src/jdk.jextract/share/classes/com/sun/tools/jextract/JextractTool.java	2018-12-18 21:39:02.000000000 +0530
+++ new/src/jdk.jextract/share/classes/com/sun/tools/jextract/JextractTool.java	2018-12-18 21:39:01.000000000 +0530
@@ -59,6 +59,7 @@
                 .map(symbolFilter)
                 .map(new TypedefHandler())
                 .map(new EmptyNameHandler())
+                .map(new DuplicateDeclarationHandler())
                 .flatMap(h -> h.declarations().stream())
                 .distinct()
                 .collect(Collectors.groupingBy(this::headerFromDecl));