diff --git a/src/net/netip/netip.go b/src/net/netip/netip.go
index 1912561c74..6295acdbd6 100644
--- a/src/net/netip/netip.go
+++ b/src/net/netip/netip.go
@@ -60,7 +60,7 @@ type Addr struct {
 // addrDetail represents the details of an Addr, like address family and IPv6 zone.
 type addrDetail struct {
 	IsV6   bool   // IPv4 is false, IPv6 is true.
-	ZoneV6 string // != nil only if IsV6 is true.
+	ZoneV6 string // != "" only if IsV6 is true.
 }
 
 // z0, z4, and z6noz are sentinel Addr.z values.