--- old/src/share/classes/com/sun/tools/javac/code/Source.java 2014-06-16 22:43:27.000000000 -0700 +++ new/src/share/classes/com/sun/tools/javac/code/Source.java 2014-06-16 22:43:27.000000000 -0700 @@ -237,6 +237,9 @@ public boolean allowFunctionalInterfaceMostSpecific() { return compareTo(JDK1_8) >= 0; } + public boolean allowPrivateSafeVarargs() { + return compareTo(JDK1_9) >= 0; + } public static SourceVersion toSourceVersion(Source source) { switch(source) { case JDK1_2: