go source for verification 2026-05-22

test/fixedbugs/bug200.go

@@ -0,0 +1,19 @@
+// errorcheck
+
+// Copyright 2009 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
+
+func main() {
+	// 6g used to compile these as two different
+	// hash codes so it missed the duplication
+	// and worse, compiled the wrong code
+	// for one of them.
+	var x interface{};
+	switch x.(type) {
+	case func(int):
+	case func(f int):	// ERROR "duplicate"
+	}
+}