diff --git a/compiler/rustc_span/src/symbol.rs b/compiler/rustc_span/src/symbol.rs
index 3a95447308a90..efae6250b0720 100644
--- a/compiler/rustc_span/src/symbol.rs
+++ b/compiler/rustc_span/src/symbol.rs
@@ -280,6 +280,8 @@ symbols! {
         IoSeek,
         IoWrite,
         IpAddr,
+        Ipv4Addr,
+        Ipv6Addr,
         IrTyKind,
         Is,
         Item,
diff --git a/library/core/src/net/ip_addr.rs b/library/core/src/net/ip_addr.rs
index 2f027be692860..aaa68e8d7d1ad 100644
--- a/library/core/src/net/ip_addr.rs
+++ b/library/core/src/net/ip_addr.rs
@@ -68,6 +68,7 @@ pub enum IpAddr {
 /// assert!("0000000.0.0.0".parse::<Ipv4Addr>().is_err()); // first octet is a zero in octal
 /// assert!("0xcb.0x0.0x71.0x00".parse::<Ipv4Addr>().is_err()); // all octets are in hex
 /// ```
+#[rustc_diagnostic_item = "Ipv4Addr"]
 #[derive(Copy, Clone, PartialEq, Eq)]
 #[stable(feature = "rust1", since = "1.0.0")]
 pub struct Ipv4Addr {
@@ -160,6 +161,7 @@ impl Hash for Ipv4Addr {
 /// assert_eq!("::1".parse(), Ok(localhost));
 /// assert_eq!(localhost.is_loopback(), true);
 /// ```
+#[rustc_diagnostic_item = "Ipv6Addr"]
 #[derive(Copy, Clone, PartialEq, Eq)]
 #[stable(feature = "rust1", since = "1.0.0")]
 pub struct Ipv6Addr {