From 65e6fdb92e8b706a944bd02bc01058857f787667 Mon Sep 17 00:00:00 2001
From: Oliver Scherer <github35764891676564198441@oli-obk.de>
Date: Fri, 16 Nov 2018 11:59:31 +0100
Subject: [PATCH] Ensure that the `static_assert!` argument is a `bool`

---
 src/librustc_data_structures/macros.rs | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/src/librustc_data_structures/macros.rs b/src/librustc_data_structures/macros.rs
index 3cc91b0e93f..286a374b280 100644
--- a/src/librustc_data_structures/macros.rs
+++ b/src/librustc_data_structures/macros.rs
@@ -11,11 +11,12 @@
 /// A simple static assertion macro. The first argument should be a unique
 /// ALL_CAPS identifier that describes the condition.
 #[macro_export]
+#[allow_internal_unstable]
 macro_rules! static_assert {
     ($name:ident: $test:expr) => {
         // Use the bool to access an array such that if the bool is false, the access
         // is out-of-bounds.
         #[allow(dead_code)]
-        static $name: () = [()][!$test as usize];
+        static $name: () = [()][!($test: bool) as usize];
     }
 }