--- a/src/jdk.compiler/share/classes/com/sun/tools/javac/code/Flags.java	Wed Sep 26 13:56:08 2018 -0400
+++ b/src/jdk.compiler/share/classes/com/sun/tools/javac/code/Flags.java	Tue Sep 25 21:33:51 2018 -0700
@@ -433,7 +433,9 @@
         SYSTEM_MODULE(Flags.SYSTEM_MODULE),
         DEPRECATED_ANNOTATION(Flags.DEPRECATED_ANNOTATION),
         DEPRECATED_REMOVAL(Flags.DEPRECATED_REMOVAL),
-        HAS_RESOURCE(Flags.HAS_RESOURCE);
+        HAS_RESOURCE(Flags.HAS_RESOURCE),
+        POTENTIALLY_AMBIGUOUS(Flags.POTENTIALLY_AMBIGUOUS),
+        ANONCONSTR_BASED(Flags.ANONCONSTR_BASED);
 
         Flag(long flag) {
             this.value = flag;

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/test/langtools/tools/javac/flags/FlagsTest.java	Tue Sep 25 21:33:51 2018 -0700
@@ -0,0 +1,46 @@
+/*
+ * Copyright (c) 2018, Google LLC. All rights reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ */
+
+/**
+ * @test
+ * @bug 8211138
+ * @summary Missing Flag enum constants
+ * @library /tools/javac/lib
+ * @modules jdk.compiler/com.sun.tools.javac.code
+ * @run main FlagsTest
+ */
+import com.sun.tools.javac.code.Flags;
+import java.lang.reflect.Field;
+import java.lang.reflect.Modifier;
+
+public class FlagsTest {
+    public static void main(String[] args) throws IllegalAccessException {
+        for (Field f : Flags.class.getFields()) {
+            if (!Modifier.isStatic(f.getModifiers())) {
+                continue;
+            }
+            long flag = ((Number) f.get(null)).longValue();
+            try {
+                Flags.asFlagSet(flag);
+            } catch (AssertionError e) {
+                throw new AssertionError("missing Flags enum constant for: " + f.getName(), e);
+            }
+        }
+    }
+}