diff --git a/src/cmd/compile/internal/gc/esc.go b/src/cmd/compile/internal/gc/esc.go
index c5021f4a48..6ce2299ba2 100644
--- a/src/cmd/compile/internal/gc/esc.go
+++ b/src/cmd/compile/internal/gc/esc.go
@@ -2168,9 +2168,7 @@ func moveToHeap(n *Node) {
 // This special tag is applied to uintptr variables
 // that we believe may hold unsafe.Pointers for
 // calls into assembly functions.
-// It is logically a constant, but using a var
-// lets us take the address below to get a *string.
-var unsafeUintptrTag = "unsafe-uintptr"
+const unsafeUintptrTag = "unsafe-uintptr"
 
 // This special tag is applied to uintptr parameters of functions
 // marked go:uintptrescapes.