1 files changed, 50 insertions, 0 deletions
diff --git a/src/runtime/testdata/testprog/checkfinalizers.go b/src/runtime/testdata/testprog/checkfinalizers.go
new file mode 100644
index 0000000000..ef0108a7e0
--- /dev/null
+++ b/src/runtime/testdata/testprog/checkfinalizers.go
@@ -0,0 +1,50 @@
+// Copyright 2024 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package main
+
+import (
+	"runtime"
+)
+
+func init() {
+	register("DetectFinalizerAndCleanupLeaks", DetectFinalizerAndCleanupLeaks)
+}
+
+// Intended to be run only with `GODEBUG=checkfinalizers=1`.
+func DetectFinalizerAndCleanupLeaks() {
+	type T *int
+
+	// Leak a cleanup.
+	cLeak := new(T)
+	runtime.AddCleanup(cLeak, func(x int) {
+		**cLeak = x
+	}, int(0))
+
+	// Have a regular cleanup to make sure it doesn't trip the detector.
+	cNoLeak := new(T)
+	runtime.AddCleanup(cNoLeak, func(_ int) {}, int(0))
+
+	// Leak a finalizer.
+	fLeak := new(T)
+	runtime.SetFinalizer(fLeak, func(_ *T) {
+		**fLeak = 12
+	})
+
+	// Have a regular finalizer to make sure it doesn't trip the detector.
+	fNoLeak := new(T)
+	runtime.SetFinalizer(fNoLeak, func(x *T) {
+		**x = 51
+	})
+
+	// runtime.GC here should crash.
+	runtime.GC()
+	println("OK")
+
+	// Keep everything alive.
+	runtime.KeepAlive(cLeak)
+	runtime.KeepAlive(cNoLeak)
+	runtime.KeepAlive(fLeak)
+	runtime.KeepAlive(fNoLeak)
+}