From caeb5544ecd9dba4d67b68b8c1b32d8132c6d5f2 Mon Sep 17 00:00:00 2001
From: Ralf Jung <post@ralfj.de>
Date: Mon, 7 Sep 2020 11:31:37 +0200
Subject: [PATCH] do not inline black_box when building for Miri

---
 library/core/src/hint.rs | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/library/core/src/hint.rs b/library/core/src/hint.rs
index d40a3802867..a7b8c2f373a 100644
--- a/library/core/src/hint.rs
+++ b/library/core/src/hint.rs
@@ -108,7 +108,8 @@ pub fn spin_loop() {
 /// Note however, that `black_box` is only (and can only be) provided on a "best-effort" basis. The
 /// extent to which it can block optimisations may vary depending upon the platform and code-gen
 /// backend used. Programs cannot rely on `black_box` for *correctness* in any way.
-#[inline]
+#[cfg_attr(not(miri), inline)]
+#[cfg_attr(miri, inline(never))]
 #[unstable(feature = "test", issue = "50297")]
 #[allow(unreachable_code)] // this makes #[cfg] a bit easier below.
 pub fn black_box<T>(dummy: T) -> T {