From fe718ef07f56457740b59b196eed0f1226137895 Mon Sep 17 00:00:00 2001
From: Corentin Henry <corentinhenry@gmail.com>
Date: Tue, 23 Apr 2019 10:40:15 +0200
Subject: [PATCH] std::net: add warning in Ipv4addr::is_reserved()
 documentation

See @the8472 comment's on Github:
https://github.com/rust-lang/rust/pull/60145#issuecomment-485424229

> I don't think is_reserved including ranges marked for future use is
> a good idea since those future uses may be realized at at some point
> and then old software with is_reserved filters may have false
> positives. This is not a hypothetical concern, such issues have been
> encountered before when IANA assigned previously reserved /8 address
> blocks.
---
 src/libstd/net/ip.rs | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/src/libstd/net/ip.rs b/src/libstd/net/ip.rs
index e3e257f5ac177..6ea49de49af64 100644
--- a/src/libstd/net/ip.rs
+++ b/src/libstd/net/ip.rs
@@ -677,6 +677,13 @@ impl Ipv4Addr {
     /// [IETF RFC 1112]: https://tools.ietf.org/html/rfc1112
     /// [`true`]: ../../std/primitive.bool.html
     ///
+    /// # Warning
+    ///
+    /// As IANA assigns new addresses, this method will be
+    /// updated. This may result in non-reserved addresses being
+    /// treated as reserved in code that relies on an outdated version
+    /// of this method.
+    ///
     /// # Examples
     ///
     /// ```