We see some inconsistency of module-info.class in java.base.jmod across different builds.

$ jmod extract java.base.jmod
$ cd classes
$ javap -v module-info.class


$ diff old-class.info new-class.info
1c1
< Classfile /home/sunjianye/bep_compare/old/classes/module-info.class
---
> Classfile /home/sunjianye/bep_compare/new/classes/module-info.class
3c3
< MD5 checksum f76c99747727a55976dca003d1bc8faa
---
> MD5 checksum 701d2aee48a029f896f426dde5fd5cb3
1130,1132d1129
< #527 // java.transaction.xa
< hash_length: 32
< hash: [d3caeb7d503e86206fbfc08aa88f0a491eb2c3cd984575e3b8069575406c6af0]
1138a1136,1138
> #527 // java.transaction.xa
> hash_length: 32
> hash: [d3caeb7d503e86206fbfc08aa88f0a491eb2c3cd984575e3b8069575406c6af0]


Proposed fix:

diff -r 3437fb6311fd src/java.base/share/classes/jdk/internal/module/ModuleHashes.java
--- a/src/java.base/share/classes/jdk/internal/module/ModuleHashes.java Mon Mar 09 04:06:37 2020 -0400
+++ b/src/java.base/share/classes/jdk/internal/module/ModuleHashes.java Mon Mar 09 17:53:12 2020 +0800
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2015, 2016, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2015, 2020, Oracle and/or its affiliates. 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
@@ -34,6 +34,7 @@
 import java.security.NoSuchAlgorithmException;
 import java.util.Collections;
 import java.util.HashMap;
+import java.util.TreeMap;
 import java.util.Map;
 import java.util.Objects;
 import java.util.Set;
@@ -134,7 +135,7 @@
      * @return ModuleHashes that encapsulates the hashes
      */
     public static ModuleHashes generate(Map<String, Path> map, String algorithm) {
- Map<String, byte[]> nameToHash = new HashMap<>();
+ Map<String, byte[]> nameToHash = new TreeMap<>();
         for (Map.Entry<String, Path> entry: map.entrySet()) {
             String name = entry.getKey();
             Path path = entry.getValue();
diff -r 3437fb6311fd src/java.base/share/classes/jdk/internal/module/ModuleHashesBuilder.java
--- a/src/java.base/share/classes/jdk/internal/module/ModuleHashesBuilder.java Mon Mar 09 04:06:37 2020 -0400
+++ b/src/java.base/share/classes/jdk/internal/module/ModuleHashesBuilder.java Mon Mar 09 17:53:12 2020 +0800
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2017, 2018, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2017, 2020, Oracle and/or its affiliates. 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
@@ -34,6 +34,7 @@
 import java.util.Collections;
 import java.util.Deque;
 import java.util.HashMap;
+import java.util.TreeMap;
 import java.util.HashSet;
 import java.util.Map;
 import java.util.Set;
@@ -98,7 +99,7 @@
         // the modules to record the hashes - it is the first matching
         // module and has not been hashed during the traversal.
         Set<String> mods = new HashSet<>();
- Map<String, ModuleHashes> hashes = new HashMap<>();
+ Map<String, ModuleHashes> hashes = new TreeMap<>();
         builder.build()
                .orderedNodes()
                .filter(mn -> roots.contains(mn) && !mods.contains(mn))