[GR-30237] NullPointerException during Ruby context pre-initialization.

PullRequest: truffleruby/2504

Author: tzezula

mx.truffleruby/suite.py

@@ -7,7 +7,7 @@
             {
                 "name": "regex",
                 "subdir": True,
-                "version": "05b3f80c848cf272f3ff97897d734b1858867c8d",
+                "version": "fa615de4e5396478d9eb303ee78048f31fe19f49",
                 "urls": [
                     {"url": "https://github.com/oracle/graal.git", "kind": "git"},
                     {"url": "https://curio.ssw.jku.at/nexus/content/repositories/snapshots", "kind": "binary"},
@@ -16,7 +16,7 @@
             {
                 "name": "sulong",
                 "subdir": True,
-                "version": "05b3f80c848cf272f3ff97897d734b1858867c8d",
+                "version": "fa615de4e5396478d9eb303ee78048f31fe19f49",
                 "urls": [
                     {"url": "https://github.com/oracle/graal.git", "kind": "git"},
                     {"url": "https://curio.ssw.jku.at/nexus/content/repositories/snapshots", "kind": "binary"},

src/main/java/org/truffleruby/RubyContext.java

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2013, 2020 Oracle and/or its affiliates. All rights reserved. This
+ * Copyright (c) 2013, 2021 Oracle and/or its affiliates. All rights reserved. This
  * code is released under a tri EPL/GPL/LGPL license. You can use it,
  * redistribute it and/or modify it under the terms of the:
  *
@@ -253,8 +253,6 @@ public void initialize() {
         if (isPreInitializing()) {
             // Cannot save the file descriptor in this SecureRandom in the image
             random = null;
-            // Cannot save the root Java Thread instance in the image
-            threadManager.resetMainThread();
             // Do not save image generator paths in the image heap
             hadHome = rubyHome != null;
             rubyHome = null;

src/main/java/org/truffleruby/RubyLanguage.java

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2015, 2020 Oracle and/or its affiliates. All rights reserved. This
+ * Copyright (c) 2015, 2021 Oracle and/or its affiliates. All rights reserved. This
  * code is released under a tri EPL/GPL/LGPL license. You can use it,
  * redistribute it and/or modify it under the terms of the:
  *
@@ -463,6 +463,10 @@ protected void initializeThread(RubyContext context, Thread thread) {
     @Override
     protected void disposeThread(RubyContext context, Thread thread) {
         if (thread == context.getThreadManager().getRootJavaThread()) {
+            if (context.getEnv().isPreInitialization()) {
+                // Cannot save the root Java Thread instance in the image
+                context.getThreadManager().resetMainThread();
+            }
             // Let the context shutdown cleanup the main thread
             return;
         }