diff --git a/test_suite/tests/ui/with/incorrect_type.stderr b/test_suite/tests/ui/with/incorrect_type.stderr
index 016a0a02..0629bdb8 100644
--- a/test_suite/tests/ui/with/incorrect_type.stderr
+++ b/test_suite/tests/ui/with/incorrect_type.stderr
@@ -6,7 +6,11 @@ error[E0277]: the trait bound `&u8: serde::Serializer` is not satisfied
 15 | struct W(#[serde(with = "w")] u8, u8);
    |                         --- required by a bound introduced by this call
    |
-   = help: the trait `Serializer` is implemented for `&mut Formatter<'a>`
+help: the trait `Serializer` is implemented for `&mut Formatter<'a>`
+  --> $WORKSPACE/serde_core/src/ser/fmt.rs
+   |
+   | impl<'a> Serializer for &mut fmt::Formatter<'a> {
+   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 note: required by a bound in `w::serialize`
   --> tests/ui/with/incorrect_type.rs:9:28
    |
@@ -33,7 +37,11 @@ error[E0277]: the trait bound `&u8: serde::Serializer` is not satisfied
 15 | struct W(#[serde(with = "w")] u8, u8);
    |                         ^^^ the trait `Serializer` is not implemented for `&u8`
    |
-   = help: the trait `Serializer` is implemented for `&mut Formatter<'a>`
+help: the trait `Serializer` is implemented for `&mut Formatter<'a>`
+  --> $WORKSPACE/serde_core/src/ser/fmt.rs
+   |
+   | impl<'a> Serializer for &mut fmt::Formatter<'a> {
+   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 
 error[E0308]: `?` operator has incompatible types
   --> tests/ui/with/incorrect_type.rs:15:25
@@ -51,7 +59,11 @@ error[E0277]: the trait bound `&u8: serde::Serializer` is not satisfied
 18 | struct S(#[serde(serialize_with = "w::serialize")] u8, u8);
    |                                   -------------- required by a bound introduced by this call
    |
-   = help: the trait `Serializer` is implemented for `&mut Formatter<'a>`
+help: the trait `Serializer` is implemented for `&mut Formatter<'a>`
+  --> $WORKSPACE/serde_core/src/ser/fmt.rs
+   |
+   | impl<'a> Serializer for &mut fmt::Formatter<'a> {
+   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 note: required by a bound in `w::serialize`
   --> tests/ui/with/incorrect_type.rs:9:28
    |
@@ -78,7 +90,11 @@ error[E0277]: the trait bound `&u8: serde::Serializer` is not satisfied
 18 | struct S(#[serde(serialize_with = "w::serialize")] u8, u8);
    |                                   ^^^^^^^^^^^^^^ the trait `Serializer` is not implemented for `&u8`
    |
-   = help: the trait `Serializer` is implemented for `&mut Formatter<'a>`
+help: the trait `Serializer` is implemented for `&mut Formatter<'a>`
+  --> $WORKSPACE/serde_core/src/ser/fmt.rs
+   |
+   | impl<'a> Serializer for &mut fmt::Formatter<'a> {
+   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 
 error[E0308]: `?` operator has incompatible types
   --> tests/ui/with/incorrect_type.rs:21:37