diff --git a/tests/mir-opt/const_array_locals.rs b/tests/mir-opt/const_array_locals.rs
index 439f18a3394c..af769bd76e69 100644
--- a/tests/mir-opt/const_array_locals.rs
+++ b/tests/mir-opt/const_array_locals.rs
@@ -2,6 +2,7 @@
 
 // EMIT_MIR const_array_locals.main.PromoteArraysOpt.diff
 // CHECK-LABEL: fn main() -> () {
+#[rustfmt::skip]
 pub fn main() {
     // CHECK: let [[array_lit:_.*]]: [i32; 32];
     // CHECK: let mut [[moved_array:_.*]]: [u16; 32];