src/java.base/share/classes/java/lang/Thread.java

@@ -166,10 +166,15 @@
     private ThreadGroup group;
 
     /* The context ClassLoader for this thread */
     private ClassLoader contextClassLoader;
 
+    /* The initiating ClassLoader of an ongoing class-loading
+     * request executing in this thread or null if there's no such
+     * ongoing request - accessed in ClassLoader */
+    ClassLoader initiatingClassLoader;
+
     /* The inherited AccessControlContext of this thread */
     private AccessControlContext inheritedAccessControlContext;
 
     /* For autonumbering anonymous threads. */
     private static int threadInitNumber;