Fix black_box bug detected by Amanieu

Co-authored-by: Amanieu <amanieu@gmail.com>
rust-lang · Sep 16, 2020 · 4dc4e9f · 4dc4e9f
1 parent 87666e5
commit 4dc4e9f
Showing 1 changed file with 1 addition and 1 deletion.
diff --git a/library/core/src/hint.rs b/library/core/src/hint.rs
@@ -122,7 +122,7 @@ pub fn black_box<T>(mut dummy: T) -> T {
     // SAFETY: the inline assembly is a no-op.
     unsafe {
         // FIXME: Cannot use `asm!` because it doesn't support MIPS and other architectures.
-        llvm_asm!("" : : "r"(&mut dummy));
+        llvm_asm!("" : : "r"(&mut dummy) : "memory" : "volatile");
     }
 
     dummy