--- a/test/lib/jdk/test/lib/util/FileUtils.java	Fri Sep 22 14:06:11 2017 +0200
+++ b/test/lib/jdk/test/lib/util/FileUtils.java	Fri Sep 22 11:49:53 2017 -0700
@@ -98,6 +98,7 @@
         while (true) {
             try {
                 Files.delete(path);
+                // Checks for absence of the file. Semantics of Files.exists() is not the same.
                 while (!Files.notExists(path)) {
                     times++;
                     if (times > MAX_RETRY_DELETE_TIMES) {