--- a/langtools/src/jdk.compiler/share/classes/com/sun/tools/javac/comp/AttrContext.java	Wed Jul 05 21:09:59 2017 +0200
+++ b/langtools/src/jdk.compiler/share/classes/com/sun/tools/javac/comp/AttrContext.java	Tue Dec 22 16:37:52 2015 +0530
@@ -25,6 +25,7 @@
 
 package com.sun.tools.javac.comp;
 
+import com.sun.tools.javac.tree.JCTree;
 import com.sun.tools.javac.util.*;
 import com.sun.tools.javac.code.*;
 import com.sun.tools.javac.code.Scope.WriteableScope;
@@ -95,6 +96,13 @@
      */
     Type defaultSuperCallSite = null;
 
+    /** Tree that when non null, is to be preferentially used in diagnostics.
+     *  Usually Env<AttrContext>.tree is the tree to be referred to in messages,
+     *  but this may not be true during the window a method is looked up in enclosing
+     *  contexts (JDK-8145466)
+     */
+    JCTree preferredTreeForDiagnostics;
+
     /** Duplicate this context, replacing scope field and copying all others.
      */
     AttrContext dup(WriteableScope scope) {
@@ -112,6 +120,7 @@
         info.isSpeculative = isSpeculative;
         info.isAnonymousDiamond = isAnonymousDiamond;
         info.isNewClass = isNewClass;
+        info.preferredTreeForDiagnostics = preferredTreeForDiagnostics;
         return info;
     }