diff -r 7f57c5908c57 -r a5f815d1060b src/jdk.compiler/share/classes/com/sun/tools/javac/comp/Check.java
--- a/src/jdk.compiler/share/classes/com/sun/tools/javac/comp/Check.java	Fri Jan 12 10:33:06 2018 +0100
+++ b/src/jdk.compiler/share/classes/com/sun/tools/javac/comp/Check.java	Fri Jan 12 16:49:58 2018 +0000
@@ -3464,6 +3464,7 @@
                      types.hasSameArgs(sym.type, byName.type) ||
                      types.hasSameArgs(types.erasure(sym.type), types.erasure(byName.type)))) {
                 if ((sym.flags() & VARARGS) != (byName.flags() & VARARGS)) {
+                    sym.flags_field |= CLASH;
                     varargsDuplicateError(pos, sym, byName);
                     return true;
                 } else if (sym.kind == MTH && !types.hasSameArgs(sym.type, byName.type, false)) {