Auto merge of #31370 - Manishearth:rollup, r=Manishearth

- Successful merges: #27499, #31220, #31329, #31332, #31347, #31351, #31352, #31366
- Failed merges:

1 files changed, 3 insertions, 0 deletions

diff --git a/src/libstd/macros.rs b/src/libstd/macros.rs
index 0917346213f..b7afd12d8e5 100644
--- a/src/libstd/macros.rs
+++ b/src/libstd/macros.rs
@@ -365,6 +365,9 @@ pub mod builtin {
     /// stringification of all the tokens passed to the macro. No restrictions
     /// are placed on the syntax of the macro invocation itself.
     ///
+    /// Note that the expanded results of the input tokens may change in the
+    /// future. You should be careful if you rely on the output.
+    ///
     /// # Examples
     ///
     /// ```