--- a/src/jdk.compiler/share/classes/com/sun/tools/javac/api/JavacTool.java	Mon Dec 11 08:20:05 2017 +0100
+++ b/src/jdk.compiler/share/classes/com/sun/tools/javac/api/JavacTool.java	Fri Dec 08 16:28:14 2017 +0100
@@ -219,7 +219,7 @@
         Set<Option> recognizedOptions = Option.getJavacToolOptions();
         for (Option o : recognizedOptions) {
             if (o.matches(option)) {
-                return o.hasArg() ? 1 : 0;
+                return o.hasSeparateArg() ? 1 : 0;
             }
         }
         return -1;