From 8b4f9c47c47df2e01efa852ffbd2d1a6b5fa2c83 Mon Sep 17 00:00:00 2001
From: David Tolnay <dtolnay@gmail.com>
Date: Sat, 26 May 2018 17:23:09 -0700
Subject: [PATCH] Build script rustc-cfg strings are not public API

---
 serde/build.rs | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/serde/build.rs b/serde/build.rs
index c007135e..ee1d6c3c 100644
--- a/serde/build.rs
+++ b/serde/build.rs
@@ -2,6 +2,9 @@ use std::env;
 use std::process::Command;
 use std::str::{self, FromStr};
 
+// The rustc-cfg strings below are *not* public API. Please let us know by
+// opening a GitHub issue if your build environment requires some way to enable
+// these cfgs other than by executing our build script.
 fn main() {
     let minor = match rustc_minor_version() {
         Some(minor) => minor,