diff --git a/src/libtest/lib.rs b/src/libtest/lib.rs
index 642eb2855640..e8a1242c8145 100644
--- a/src/libtest/lib.rs
+++ b/src/libtest/lib.rs
@@ -1554,16 +1554,14 @@ impl MetricMap {
 /// elimination.
 ///
 /// This function is a no-op, and does not even read from `dummy`.
-#[cfg(not(any(all(target_os = "nacl", target_arch = "le32"),
-              target_arch = "asmjs", target_arch = "wasm32")))]
+#[cfg(not(any(target_arch = "asmjs", target_arch = "wasm32")))]
 pub fn black_box<T>(dummy: T) -> T {
     // we need to "use" the argument in some way LLVM can't
     // introspect.
     unsafe { asm!("" : : "r"(&dummy)) }
     dummy
 }
-#[cfg(any(all(target_os = "nacl", target_arch = "le32"),
-          target_arch = "asmjs", target_arch = "wasm32"))]
+#[cfg(any(target_arch = "asmjs", target_arch = "wasm32"))]
 #[inline(never)]
 pub fn black_box<T>(dummy: T) -> T {
     dummy