diff --git a/gcc/rust/parse/rust-parse-impl.h b/gcc/rust/parse/rust-parse-impl.h
index 18acc9318ae1..243bc4420219 100644
--- a/gcc/rust/parse/rust-parse-impl.h
+++ b/gcc/rust/parse/rust-parse-impl.h
@@ -4922,8 +4922,8 @@ Parser<ManagedTokenSource>::parse_trait (AST::Visibility vis,
 
   if (is_auto_trait && !trait_items.empty ())
     {
-      add_error (
-	Error (locus, "associated items are forbidden within auto traits"));
+      add_error (Error (locus, ErrorCode::E0380,
+			"auto traits cannot have associated items"));
 
       // FIXME: unsure if this should be done at parsing time or not
       for (const auto &item : trait_items)
diff --git a/gcc/testsuite/rust/compile/auto_trait_invalid.rs b/gcc/testsuite/rust/compile/auto_trait_invalid.rs
index 16dca5718491..66e45531f5d8 100644
--- a/gcc/testsuite/rust/compile/auto_trait_invalid.rs
+++ b/gcc/testsuite/rust/compile/auto_trait_invalid.rs
@@ -2,7 +2,7 @@
 
 #![feature(optin_builtin_traits)]
 
-unsafe auto trait Invalid { // { dg-error "associated items are forbidden within auto traits" }
+unsafe auto trait Invalid { // { dg-error "auto traits cannot have associated items" }
     fn foo(); // { dg-message "remove this item" }
 
     fn bar() {} // { dg-message "remove this item" }