diff --git a/src/test/ui/error-codes/E0779.stderr b/src/test/ui/error-codes/E0779.stderr
index 4abe0c026365..da787260d4f6 100644
--- a/src/test/ui/error-codes/E0779.stderr
+++ b/src/test/ui/error-codes/E0779.stderr
@@ -1,4 +1,4 @@
-error[E0779]: Invalid instruction set specified
+error[E0779]: invalid instruction set specified
   --> $DIR/E0779.rs:3:1
    |
 LL | #[instruction_set(arm::magic)]