From b6bbee7f8c58cf02b00c90f5849fff7ec7153106 Mon Sep 17 00:00:00 2001
From: Project516 <138796702+Project516@users.noreply.github.com>
Date: Thu, 5 Nov 2026 11:17:53 -0600
Subject: [PATCH] Terminate main before waiting for non-daemon threads.

---
 src/jvm.ts                    |  3 ++-
 test/java/MainThreadExit.java | 15 +++++++++++++++
 test/jtreg/passing.txt        |  1 +
 3 files changed, 18 insertions(+), 1 deletion(-)
 create mode 100644 test/java/MainThreadExit.java

diff --git a/src/jvm.ts b/src/jvm.ts
index 589c381..fb01ec6 100644
--- a/src/jvm.ts
+++ b/src/jvm.ts
@@ -1360,6 +1360,8 @@ export class JVM {
         // nothing left to report to
       }
     }
+    // Main must be joinable before DestroyJavaVM waits for other threads.
+    yield* this.exitThread(t);
     // DestroyJavaVM: wait for the other non-daemon threads, then shut down.
     while (this.nonDaemonAlive(t)) {
       yield t.block(new Promise<void>((r) => {
@@ -1367,7 +1369,6 @@ export class JVM {
         check();
       }));
     }
-    yield* this.exitThread(t);
     yield t.call(boot("java/lang/Shutdown").methodMap.get("shutdown()V")!);
     this.halt(code);
   }
diff --git a/test/java/MainThreadExit.java b/test/java/MainThreadExit.java
new file mode 100644
index 0000000..d7ae3ab
--- /dev/null
+++ b/test/java/MainThreadExit.java
@@ -0,0 +1,15 @@
+public class MainThreadExit {
+    public static void main(String[] args) {
+        Thread main = Thread.currentThread();
+        main.setUncaughtExceptionHandler((thread, error) -> System.out.println("uncaught: " + error.getMessage()));
+        new Thread(() -> {
+            try {
+                main.join();
+                System.out.println("main alive: " + main.isAlive());
+            } catch (InterruptedException e) {
+                throw new AssertionError(e);
+            }
+        }).start();
+        throw new RuntimeException("main failed");
+    }
+}
diff --git a/test/jtreg/passing.txt b/test/jtreg/passing.txt
index 1266d2a..91bfd46 100644
--- a/test/jtreg/passing.txt
+++ b/test/jtreg/passing.txt
@@ -1053,6 +1053,7 @@ java/lang/Thread/SleepSanity.java
 java/lang/Thread/SleepWithDuration.java
 java/lang/Thread/ThreadStateTest.java
 java/lang/Thread/ThreadStopTest.java
+java/lang/Thread/UncaughtExceptionsTest.java
 java/lang/Thread/virtual/Collectable.java
 java/lang/Thread/virtual/Locking.java
 java/lang/Thread/virtual/Reflection.java