diff --git a/test/MC/AArch64/basic-a64-diagnostics.s b/test/MC/AArch64/basic-a64-diagnostics.s
index 0a9cf1935fd..1e9024c5eed 100644
--- a/test/MC/AArch64/basic-a64-diagnostics.s
+++ b/test/MC/AArch64/basic-a64-diagnostics.s
@@ -1,4 +1,5 @@
-// RUN: not llvm-mc -triple=aarch64 < %s 2>&1 | FileCheck --check-prefix=CHECK-ERROR %s
+// RUN: not llvm-mc -triple=aarch64 < %s 2> %t
+// RUN: FileCheck --check-prefix=CHECK-ERROR < %t %s
 
 //------------------------------------------------------------------------------
 // Add/sub (extended register)