diff --git a/cmd/tailscaled/debug_forcereflect.go b/cmd/tailscaled/debug_forcereflect.go
new file mode 100644
index 000000000..7378753ce
--- /dev/null
+++ b/cmd/tailscaled/debug_forcereflect.go
@@ -0,0 +1,26 @@
+// Copyright (c) Tailscale Inc & AUTHORS
+// SPDX-License-Identifier: BSD-3-Clause
+
+//go:build ts_debug_forcereflect
+
+// This file exists for benchmarking binary sizes. When the build tag is
+// enabled, it forces use of part of the reflect package that makes the Go
+// linker go into conservative retention mode where its deadcode pass can't
+// eliminate exported method.
+
+package main
+
+import (
+	"reflect"
+	"time"
+)
+
+func init() {
+	// See Go's src/cmd/compile/internal/walk/expr.go:usemethod for
+	// why this is isn't a const.
+	name := []byte("Bar")
+	if time.Now().Unix()&1 == 0 {
+		name[0] = 'X'
+	}
+	_, _ = reflect.TypeOf(12).MethodByName(string(name))
+}