Initial commit: Go 1.23 release state

test/fixedbugs/issue31412b.go

@@ -0,0 +1,20 @@
+// errorcheck
+
+// Copyright 2019 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.
+
+// This code was incorrectly accepted by gccgo.
+
+package main
+
+type N string
+type M string
+
+const B N = "B"
+const C M = "C"
+
+func main() {
+	q := B + C // ERROR "mismatched types|incompatible types"
+	println(q)
+}