diff --git a/library/stdarch/crates/core_arch/src/x86/macros.rs b/library/stdarch/crates/core_arch/src/x86/macros.rs
index c27ea7be1001..e659ac3da8ee 100644
--- a/library/stdarch/crates/core_arch/src/x86/macros.rs
+++ b/library/stdarch/crates/core_arch/src/x86/macros.rs
@@ -72,6 +72,7 @@ macro_rules! constify_imm6 {
     };
 }
 
+#[allow(unused_macros)]
 macro_rules! constify_imm4 {
     ($imm8:expr, $expand:ident) => {
         #[allow(overflowing_literals)]