diff --git a/src/cmd/compile/internal/noder/stencil.go b/src/cmd/compile/internal/noder/stencil.go
index e273a80b20f..36a6f2e6d02 100644
--- a/src/cmd/compile/internal/noder/stencil.go
+++ b/src/cmd/compile/internal/noder/stencil.go
@@ -350,6 +350,9 @@ func (subst *subster) node(n ir.Node) ir.Node {
 				return v
 			}
 			return x
+		case ir.ONONAME:
+			// This handles the identifier in a type switch guard
+			fallthrough
 		case ir.OLITERAL, ir.ONIL:
 			if x.Sym() != nil {
 				return x
diff --git a/test/typeparam/issue46472.go b/test/typeparam/issue46472.go
new file mode 100644
index 00000000000..bab48e7d2f5
--- /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")
+}