[dev.typeparams] cmd/compile: handle ONONAME in subster.node

Fixes #46472

Change-Id: I27802978fa0c3bb32a29e452165a6fcac93473bb
Reviewed-on: https://go-review.googlesource.com/c/go/+/323731
Trust: Cuong Manh Le <cuong.manhle.vn@gmail.com>
Run-TryBot: Cuong Manh Le <cuong.manhle.vn@gmail.com>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Dan Scales <danscales@google.com>

1 files changed, 20 insertions, 0 deletions

diff --git a/test/typeparam/issue46472.go b/test/typeparam/issue46472.go
new file mode 100644
index 0000000000..bab48e7d2f
--- /dev/null
+++ b/test/typeparam/issue46472.go
@@ -0,0 +1,20 @@
+// run -gcflags=-G=3
+
+// Copyright 2021 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 foo[T any](d T) {
+	switch v := interface{}(d).(type) {
+	case string:
+		if v != "x" {
+			panic("unexpected v: "+v)
+		}
+	}
+
+}
+func main() {
+	foo("x")
+}