Rollup merge of #114088 - oli-obk:syn, r=davidtwco

Bump syn dependency

r? `@davidtwco` because this affects diagnostics derive diagnostics (yes this sentence is grammatically correct)

4 files changed, 185 insertions, 178 deletions

diff --git a/tests/ui-fulldeps/session-diagnostic/diagnostic-derive.rs b/tests/ui-fulldeps/session-diagnostic/diagnostic-derive.rs
index ffbefce48d3..c30120e5cf3 100644
--- a/tests/ui-fulldeps/session-diagnostic/diagnostic-derive.rs
+++ b/tests/ui-fulldeps/session-diagnostic/diagnostic-derive.rs
@@ -53,7 +53,7 @@ enum DiagnosticOnEnum {
 #[derive(Diagnostic)]
 #[diag(no_crate_example, code = "E0123")]
 #[diag = "E0123"]
-//~^ ERROR expected parentheses: #[diag(...)]
+//~^ ERROR failed to resolve: maybe a missing crate `core`
 struct WrongStructAttrStyle {}
 
 #[derive(Diagnostic)]
@@ -644,7 +644,7 @@ struct MissingCodeInSuggestion {
 //~| ERROR cannot find attribute `multipart_suggestion` in this scope
 #[multipart_suggestion()]
 //~^ ERROR cannot find attribute `multipart_suggestion` in this scope
-//~| ERROR unexpected end of input, unexpected token in nested attribute, expected ident
+//~| ERROR `#[multipart_suggestion(...)]` is not a valid attribute
 struct MultipartSuggestion {
     #[multipart_suggestion(no_crate_suggestion)]
     //~^ ERROR `#[multipart_suggestion(...)]` is not a valid attribute
@@ -797,7 +797,7 @@ struct SuggestionsNoItem {
 struct SuggestionsInvalidItem {
     #[suggestion(code(foo))]
     //~^ ERROR `code(...)` must contain only string literals
-    //~| ERROR unexpected token
+    //~| ERROR failed to resolve: maybe a missing crate `core`
     sub: Span,
 }
 
@@ -805,7 +805,7 @@ struct SuggestionsInvalidItem {
 #[diag(no_crate_example)]
 struct SuggestionsInvalidLiteral {
     #[suggestion(code = 3)]
-    //~^ ERROR expected string literal
+    //~^ ERROR failed to resolve: maybe a missing crate `core`
     sub: Span,
 }
 
diff --git a/tests/ui-fulldeps/session-diagnostic/diagnostic-derive.stderr b/tests/ui-fulldeps/session-diagnostic/diagnostic-derive.stderr
index 1398f9c96bf..ca09f1f0153 100644
--- a/tests/ui-fulldeps/session-diagnostic/diagnostic-derive.stderr
+++ b/tests/ui-fulldeps/session-diagnostic/diagnostic-derive.stderr
@@ -20,12 +20,6 @@ LL |     Bar,
    |
    = help: specify the slug as the first argument to the `#[diag(...)]` attribute, such as `#[diag(hir_analysis_example_error)]`
 
-error: expected parentheses: #[diag(...)]
-  --> $DIR/diagnostic-derive.rs:55:8
-   |
-LL | #[diag = "E0123"]
-   |        ^
-
 error: `#[nonsense(...)]` is not a valid attribute
   --> $DIR/diagnostic-derive.rs:60:1
    |
@@ -477,6 +471,14 @@ LL | #[multipart_suggestion(no_crate_suggestion)]
    = help: consider creating a `Subdiagnostic` instead
 
 error: `#[multipart_suggestion(...)]` is not a valid attribute
+  --> $DIR/diagnostic-derive.rs:645:1
+   |
+LL | #[multipart_suggestion()]
+   | ^^^^^^^^^^^^^^^^^^^^^^^^^
+   |
+   = help: consider creating a `Subdiagnostic` instead
+
+error: `#[multipart_suggestion(...)]` is not a valid attribute
   --> $DIR/diagnostic-derive.rs:649:5
    |
 LL |     #[multipart_suggestion(no_crate_suggestion)]
@@ -484,12 +486,6 @@ LL |     #[multipart_suggestion(no_crate_suggestion)]
    |
    = help: consider creating a `Subdiagnostic` instead
 
-error: unexpected end of input, unexpected token in nested attribute, expected ident
-  --> $DIR/diagnostic-derive.rs:645:24
-   |
-LL | #[multipart_suggestion()]
-   |                        ^
-
 error: `#[suggestion(...)]` is not a valid attribute
   --> $DIR/diagnostic-derive.rs:657:1
    |
@@ -550,18 +546,6 @@ error: `code(...)` must contain only string literals
 LL |     #[suggestion(code(foo))]
    |                       ^^^
 
-error: unexpected token
-  --> $DIR/diagnostic-derive.rs:798:23
-   |
-LL |     #[suggestion(code(foo))]
-   |                       ^^^
-
-error: expected string literal
-  --> $DIR/diagnostic-derive.rs:807:25
-   |
-LL |     #[suggestion(code = 3)]
-   |                         ^
-
 error: `#[suggestion(...)]` is not a valid attribute
   --> $DIR/diagnostic-derive.rs:822:5
    |
@@ -572,6 +556,24 @@ LL |     #[suggestion(no_crate_suggestion, code = "")]
    = help: to show a suggestion consisting of multiple parts, use a `Subdiagnostic` annotated with `#[multipart_suggestion(...)]`
    = help: to show a variable set of suggestions, use a `Vec` of `Subdiagnostic`s annotated with `#[suggestion(...)]`
 
+error[E0433]: failed to resolve: maybe a missing crate `core`?
+  --> $DIR/diagnostic-derive.rs:55:8
+   |
+LL | #[diag = "E0123"]
+   |        ^ maybe a missing crate `core`?
+
+error[E0433]: failed to resolve: maybe a missing crate `core`?
+  --> $DIR/diagnostic-derive.rs:798:23
+   |
+LL |     #[suggestion(code(foo))]
+   |                       ^^^ maybe a missing crate `core`?
+
+error[E0433]: failed to resolve: maybe a missing crate `core`?
+  --> $DIR/diagnostic-derive.rs:807:25
+   |
+LL |     #[suggestion(code = 3)]
+   |                         ^ maybe a missing crate `core`?
+
 error: cannot find attribute `nonsense` in this scope
   --> $DIR/diagnostic-derive.rs:60:3
    |
@@ -656,5 +658,5 @@ note: required by a bound in `DiagnosticBuilder::<'a, G>::set_arg`
 
 error: aborting due to 84 previous errors
 
-Some errors have detailed explanations: E0277, E0425.
+Some errors have detailed explanations: E0277, E0425, E0433.
 For more information about an error, try `rustc --explain E0277`.
diff --git a/tests/ui-fulldeps/session-diagnostic/subdiagnostic-derive.rs b/tests/ui-fulldeps/session-diagnostic/subdiagnostic-derive.rs
index 38af5b0f9fb..dd0f7a7efb7 100644
--- a/tests/ui-fulldeps/session-diagnostic/subdiagnostic-derive.rs
+++ b/tests/ui-fulldeps/session-diagnostic/subdiagnostic-derive.rs
@@ -95,7 +95,8 @@ struct G {
 
 #[derive(Subdiagnostic)]
 #[label("...")]
-//~^ ERROR unexpected literal in nested attribute, expected ident
+//~^ ERROR failed to resolve: maybe a missing crate `core`?
+//~| NOTE maybe a missing crate `core`?
 struct H {
     #[primary_span]
     span: Span,
@@ -134,7 +135,7 @@ struct L {
 
 #[derive(Subdiagnostic)]
 #[label()]
-//~^ ERROR unexpected end of input, unexpected token in nested attribute, expected ident
+//~^ ERROR diagnostic slug must be first argument of a `#[label(...)]` attribute
 struct M {
     #[primary_span]
     span: Span,
@@ -310,7 +311,8 @@ struct AB {
 
 #[derive(Subdiagnostic)]
 union AC {
-    //~^ ERROR unexpected unsupported untagged union
+    //~^ ERROR failed to resolve: maybe a missing crate `core`?
+    //~| NOTE maybe a missing crate `core`?
     span: u32,
     b: u64,
 }
@@ -556,7 +558,7 @@ struct BBb {
 #[multipart_suggestion(no_crate_example, applicability = "machine-applicable")]
 struct BBc {
     #[suggestion_part()]
-    //~^ ERROR unexpected end of input, unexpected token in nested attribute, expected ident
+    //~^ ERROR `#[suggestion_part(...)]` attribute without `code = "..."`
     span1: Span,
 }
 
@@ -576,11 +578,12 @@ struct BD {
     //~^ ERROR `#[suggestion_part(...)]` attribute without `code = "..."`
     span1: Span,
     #[suggestion_part()]
-    //~^ ERROR unexpected end of input, unexpected token in nested attribute, expected ident
+    //~^ ERROR `#[suggestion_part(...)]` attribute without `code = "..."`
     span2: Span,
     #[suggestion_part(foo = "bar")]
     //~^ ERROR `code` is the only valid nested attribute
-    //~| ERROR expected `,`
+    //~| ERROR failed to resolve: maybe a missing crate `core`?
+    //~| NOTE maybe a missing crate `core`?
     span4: Span,
     #[suggestion_part(code = "...")]
     //~^ ERROR the `#[suggestion_part(...)]` attribute can only be applied to fields of type `Span` or `MultiSpan`
@@ -672,7 +675,8 @@ enum BL {
 struct BM {
     #[suggestion_part(code("foo"))]
     //~^ ERROR expected exactly one string literal for `code = ...`
-    //~| ERROR unexpected token
+    //~| ERROR failed to resolve: maybe a missing crate `core`?
+    //~| NOTE maybe a missing crate `core`?
     span: Span,
     r#type: String,
 }
@@ -682,7 +686,8 @@ struct BM {
 struct BN {
     #[suggestion_part(code("foo", "bar"))]
     //~^ ERROR expected exactly one string literal for `code = ...`
-    //~| ERROR unexpected token
+    //~| ERROR failed to resolve: maybe a missing crate `core`?
+    //~| NOTE maybe a missing crate `core`?
     span: Span,
     r#type: String,
 }
@@ -692,7 +697,8 @@ struct BN {
 struct BO {
     #[suggestion_part(code(3))]
     //~^ ERROR expected exactly one string literal for `code = ...`
-    //~| ERROR unexpected token
+    //~| ERROR failed to resolve: maybe a missing crate `core`?
+    //~| NOTE maybe a missing crate `core`?
     span: Span,
     r#type: String,
 }
@@ -713,7 +719,8 @@ struct BP {
 #[multipart_suggestion(no_crate_example)]
 struct BQ {
     #[suggestion_part(code = 3)]
-    //~^ ERROR expected string literal
+    //~^ ERROR failed to resolve: maybe a missing crate `core`?
+    //~| NOTE maybe a missing crate `core`?
     span: Span,
     r#type: String,
 }
@@ -805,7 +812,8 @@ struct SuggestionStyleInvalid3 {
 #[derive(Subdiagnostic)]
 #[suggestion(no_crate_example, code = "", style("foo"))]
 //~^ ERROR expected `= "xxx"`
-//~| ERROr expected `,`
+//~| ERROR failed to resolve: maybe a missing crate `core`?
+//~| NOTE maybe a missing crate `core`?
 struct SuggestionStyleInvalid4 {
     #[primary_span]
     sub: Span,
diff --git a/tests/ui-fulldeps/session-diagnostic/subdiagnostic-derive.stderr b/tests/ui-fulldeps/session-diagnostic/subdiagnostic-derive.stderr
index 5ddc8edd745..1f267aceb9e 100644
--- a/tests/ui-fulldeps/session-diagnostic/subdiagnostic-derive.stderr
+++ b/tests/ui-fulldeps/session-diagnostic/subdiagnostic-derive.stderr
@@ -38,104 +38,98 @@ error: diagnostic slug must be first argument of a `#[label(...)]` attribute
 LL | #[label(bug = "...")]
    | ^^^^^^^^^^^^^^^^^^^^^
 
-error: unexpected literal in nested attribute, expected ident
-  --> $DIR/subdiagnostic-derive.rs:97:9
-   |
-LL | #[label("...")]
-   |         ^^^^^
-
 error: only `no_span` is a valid nested attribute
-  --> $DIR/subdiagnostic-derive.rs:106:9
+  --> $DIR/subdiagnostic-derive.rs:107:9
    |
 LL | #[label(slug = 4)]
    |         ^^^^
 
 error: diagnostic slug must be first argument of a `#[label(...)]` attribute
-  --> $DIR/subdiagnostic-derive.rs:106:1
+  --> $DIR/subdiagnostic-derive.rs:107:1
    |
 LL | #[label(slug = 4)]
    | ^^^^^^^^^^^^^^^^^^
 
 error: only `no_span` is a valid nested attribute
-  --> $DIR/subdiagnostic-derive.rs:116:9
+  --> $DIR/subdiagnostic-derive.rs:117:9
    |
 LL | #[label(slug("..."))]
    |         ^^^^
 
 error: diagnostic slug must be first argument of a `#[label(...)]` attribute
-  --> $DIR/subdiagnostic-derive.rs:116:1
+  --> $DIR/subdiagnostic-derive.rs:117:1
    |
 LL | #[label(slug("..."))]
    | ^^^^^^^^^^^^^^^^^^^^^
 
-error: unexpected end of input, unexpected token in nested attribute, expected ident
-  --> $DIR/subdiagnostic-derive.rs:136:9
+error: diagnostic slug must be first argument of a `#[label(...)]` attribute
+  --> $DIR/subdiagnostic-derive.rs:137:1
    |
 LL | #[label()]
-   |         ^
+   | ^^^^^^^^^^
 
 error: only `no_span` is a valid nested attribute
-  --> $DIR/subdiagnostic-derive.rs:145:27
+  --> $DIR/subdiagnostic-derive.rs:146:27
    |
 LL | #[label(no_crate_example, code = "...")]
    |                           ^^^^
 
 error: only `no_span` is a valid nested attribute
-  --> $DIR/subdiagnostic-derive.rs:154:27
+  --> $DIR/subdiagnostic-derive.rs:155:27
    |
 LL | #[label(no_crate_example, applicability = "machine-applicable")]
    |                           ^^^^^^^^^^^^^
 
 error: unsupported type attribute for subdiagnostic enum
-  --> $DIR/subdiagnostic-derive.rs:163:1
+  --> $DIR/subdiagnostic-derive.rs:164:1
    |
 LL | #[foo]
    | ^^^^^^
 
 error: `#[bar]` is not a valid attribute
-  --> $DIR/subdiagnostic-derive.rs:177:5
+  --> $DIR/subdiagnostic-derive.rs:178:5
    |
 LL |     #[bar]
    |     ^^^^^^
 
 error: `#[bar = ...]` is not a valid attribute
-  --> $DIR/subdiagnostic-derive.rs:189:5
+  --> $DIR/subdiagnostic-derive.rs:190:5
    |
 LL |     #[bar = "..."]
    |     ^^^^^^^^^^^^^^
 
 error: `#[bar = ...]` is not a valid attribute
-  --> $DIR/subdiagnostic-derive.rs:201:5
+  --> $DIR/subdiagnostic-derive.rs:202:5
    |
 LL |     #[bar = 4]
    |     ^^^^^^^^^^
 
 error: `#[bar(...)]` is not a valid attribute
-  --> $DIR/subdiagnostic-derive.rs:213:5
+  --> $DIR/subdiagnostic-derive.rs:214:5
    |
 LL |     #[bar("...")]
    |     ^^^^^^^^^^^^^
 
 error: only `no_span` is a valid nested attribute
-  --> $DIR/subdiagnostic-derive.rs:225:13
+  --> $DIR/subdiagnostic-derive.rs:226:13
    |
 LL |     #[label(code = "...")]
    |             ^^^^
 
 error: diagnostic slug must be first argument of a `#[label(...)]` attribute
-  --> $DIR/subdiagnostic-derive.rs:225:5
+  --> $DIR/subdiagnostic-derive.rs:226:5
    |
 LL |     #[label(code = "...")]
    |     ^^^^^^^^^^^^^^^^^^^^^^
 
 error: the `#[primary_span]` attribute can only be applied to fields of type `Span` or `MultiSpan`
-  --> $DIR/subdiagnostic-derive.rs:254:5
+  --> $DIR/subdiagnostic-derive.rs:255:5
    |
 LL |     #[primary_span]
    |     ^^^^^^^^^^^^^^^
 
 error: label without `#[primary_span]` field
-  --> $DIR/subdiagnostic-derive.rs:251:1
+  --> $DIR/subdiagnostic-derive.rs:252:1
    |
 LL | / #[label(no_crate_example)]
 LL | |
@@ -147,13 +141,13 @@ LL | | }
    | |_^
 
 error: `#[applicability]` is only valid on suggestions
-  --> $DIR/subdiagnostic-derive.rs:264:5
+  --> $DIR/subdiagnostic-derive.rs:265:5
    |
 LL |     #[applicability]
    |     ^^^^^^^^^^^^^^^^
 
 error: `#[bar]` is not a valid attribute
-  --> $DIR/subdiagnostic-derive.rs:274:5
+  --> $DIR/subdiagnostic-derive.rs:275:5
    |
 LL |     #[bar]
    |     ^^^^^^
@@ -161,97 +155,87 @@ LL |     #[bar]
    = help: only `primary_span`, `applicability` and `skip_arg` are valid field attributes
 
 error: `#[bar = ...]` is not a valid attribute
-  --> $DIR/subdiagnostic-derive.rs:285:5
+  --> $DIR/subdiagnostic-derive.rs:286:5
    |
 LL |     #[bar = "..."]
    |     ^^^^^^^^^^^^^^
 
 error: `#[bar(...)]` is not a valid attribute
-  --> $DIR/subdiagnostic-derive.rs:296:5
+  --> $DIR/subdiagnostic-derive.rs:297:5
    |
 LL |     #[bar("...")]
    |     ^^^^^^^^^^^^^
    |
    = help: only `primary_span`, `applicability` and `skip_arg` are valid field attributes
 
-error: unexpected unsupported untagged union
-  --> $DIR/subdiagnostic-derive.rs:312:1
-   |
-LL | / union AC {
-LL | |
-LL | |     span: u32,
-LL | |     b: u64,
-LL | | }
-   | |_^
-
 error: a diagnostic slug must be the first argument to the attribute
-  --> $DIR/subdiagnostic-derive.rs:327:44
+  --> $DIR/subdiagnostic-derive.rs:329:44
    |
 LL | #[label(no_crate_example, no_crate::example)]
    |                                            ^
 
 error: specified multiple times
-  --> $DIR/subdiagnostic-derive.rs:340:5
+  --> $DIR/subdiagnostic-derive.rs:342:5
    |
 LL |     #[primary_span]
    |     ^^^^^^^^^^^^^^^
    |
 note: previously specified here
-  --> $DIR/subdiagnostic-derive.rs:337:5
+  --> $DIR/subdiagnostic-derive.rs:339:5
    |
 LL |     #[primary_span]
    |     ^^^^^^^^^^^^^^^
 
 error: subdiagnostic kind not specified
-  --> $DIR/subdiagnostic-derive.rs:346:8
+  --> $DIR/subdiagnostic-derive.rs:348:8
    |
 LL | struct AG {
    |        ^^
 
 error: specified multiple times
-  --> $DIR/subdiagnostic-derive.rs:383:46
+  --> $DIR/subdiagnostic-derive.rs:385:46
    |
 LL | #[suggestion(no_crate_example, code = "...", code = "...")]
    |                                              ^^^^
    |
 note: previously specified here
-  --> $DIR/subdiagnostic-derive.rs:383:32
+  --> $DIR/subdiagnostic-derive.rs:385:32
    |
 LL | #[suggestion(no_crate_example, code = "...", code = "...")]
    |                                ^^^^
 
 error: specified multiple times
-  --> $DIR/subdiagnostic-derive.rs:401:5
+  --> $DIR/subdiagnostic-derive.rs:403:5
    |
 LL |     #[applicability]
    |     ^^^^^^^^^^^^^^^^
    |
 note: previously specified here
-  --> $DIR/subdiagnostic-derive.rs:398:5
+  --> $DIR/subdiagnostic-derive.rs:400:5
    |
 LL |     #[applicability]
    |     ^^^^^^^^^^^^^^^^
 
 error: the `#[applicability]` attribute can only be applied to fields of type `Applicability`
-  --> $DIR/subdiagnostic-derive.rs:411:5
+  --> $DIR/subdiagnostic-derive.rs:413:5
    |
 LL |     #[applicability]
    |     ^^^^^^^^^^^^^^^^
 
 error: suggestion without `code = "..."`
-  --> $DIR/subdiagnostic-derive.rs:424:1
+  --> $DIR/subdiagnostic-derive.rs:426:1
    |
 LL | #[suggestion(no_crate_example)]
    | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 
 error: invalid applicability
-  --> $DIR/subdiagnostic-derive.rs:434:62
+  --> $DIR/subdiagnostic-derive.rs:436:62
    |
 LL | #[suggestion(no_crate_example, code = "...", applicability = "foo")]
    |                                                              ^^^^^
 
 error: suggestion without `#[primary_span]` field
-  --> $DIR/subdiagnostic-derive.rs:452:1
+  --> $DIR/subdiagnostic-derive.rs:454:1
    |
 LL | / #[suggestion(no_crate_example, code = "...")]
 LL | |
@@ -261,25 +245,25 @@ LL | | }
    | |_^
 
 error: unsupported type attribute for subdiagnostic enum
-  --> $DIR/subdiagnostic-derive.rs:466:1
+  --> $DIR/subdiagnostic-derive.rs:468:1
    |
 LL | #[label]
    | ^^^^^^^^
 
 error: `var` doesn't refer to a field on this type
-  --> $DIR/subdiagnostic-derive.rs:486:39
+  --> $DIR/subdiagnostic-derive.rs:488:39
    |
 LL | #[suggestion(no_crate_example, code = "{var}", applicability = "machine-applicable")]
    |                                       ^^^^^^^
 
 error: `var` doesn't refer to a field on this type
-  --> $DIR/subdiagnostic-derive.rs:505:43
+  --> $DIR/subdiagnostic-derive.rs:507:43
    |
 LL |     #[suggestion(no_crate_example, code = "{var}", applicability = "machine-applicable")]
    |                                           ^^^^^^^
 
 error: `#[suggestion_part]` is not a valid attribute
-  --> $DIR/subdiagnostic-derive.rs:528:5
+  --> $DIR/subdiagnostic-derive.rs:530:5
    |
 LL |     #[suggestion_part]
    |     ^^^^^^^^^^^^^^^^^^
@@ -287,7 +271,7 @@ LL |     #[suggestion_part]
    = help: `#[suggestion_part(...)]` is only valid in multipart suggestions, use `#[primary_span]` instead
 
 error: `#[suggestion_part(...)]` is not a valid attribute
-  --> $DIR/subdiagnostic-derive.rs:531:5
+  --> $DIR/subdiagnostic-derive.rs:533:5
    |
 LL |     #[suggestion_part(code = "...")]
    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
@@ -295,7 +279,7 @@ LL |     #[suggestion_part(code = "...")]
    = help: `#[suggestion_part(...)]` is only valid in multipart suggestions
 
 error: suggestion without `#[primary_span]` field
-  --> $DIR/subdiagnostic-derive.rs:525:1
+  --> $DIR/subdiagnostic-derive.rs:527:1
    |
 LL | / #[suggestion(no_crate_example, code = "...")]
 LL | |
@@ -307,7 +291,7 @@ LL | | }
    | |_^
 
 error: invalid nested attribute
-  --> $DIR/subdiagnostic-derive.rs:540:42
+  --> $DIR/subdiagnostic-derive.rs:542:42
    |
 LL | #[multipart_suggestion(no_crate_example, code = "...", applicability = "machine-applicable")]
    |                                          ^^^^
@@ -315,7 +299,7 @@ LL | #[multipart_suggestion(no_crate_example, code = "...", applicability = "mac
    = help: only `no_span`, `style` and `applicability` are valid nested attributes
 
 error: multipart suggestion without any `#[suggestion_part(...)]` fields
-  --> $DIR/subdiagnostic-derive.rs:540:1
+  --> $DIR/subdiagnostic-derive.rs:542:1
    |
 LL | / #[multipart_suggestion(no_crate_example, code = "...", applicability = "machine-applicable")]
 LL | |
@@ -326,19 +310,19 @@ LL | | }
    | |_^
 
 error: `#[suggestion_part(...)]` attribute without `code = "..."`
-  --> $DIR/subdiagnostic-derive.rs:550:5
+  --> $DIR/subdiagnostic-derive.rs:552:5
    |
 LL |     #[suggestion_part]
    |     ^^^^^^^^^^^^^^^^^^
 
-error: unexpected end of input, unexpected token in nested attribute, expected ident
-  --> $DIR/subdiagnostic-derive.rs:558:23
+error: `#[suggestion_part(...)]` attribute without `code = "..."`
+  --> $DIR/subdiagnostic-derive.rs:560:5
    |
 LL |     #[suggestion_part()]
-   |                       ^
+   |     ^^^^^^^^^^^^^^^^^^^^
 
 error: `#[primary_span]` is not a valid attribute
-  --> $DIR/subdiagnostic-derive.rs:567:5
+  --> $DIR/subdiagnostic-derive.rs:569:5
    |
 LL |     #[primary_span]
    |     ^^^^^^^^^^^^^^^
@@ -346,7 +330,7 @@ LL |     #[primary_span]
    = help: multipart suggestions use one or more `#[suggestion_part]`s rather than one `#[primary_span]`
 
 error: multipart suggestion without any `#[suggestion_part(...)]` fields
-  --> $DIR/subdiagnostic-derive.rs:564:1
+  --> $DIR/subdiagnostic-derive.rs:566:1
    |
 LL | / #[multipart_suggestion(no_crate_example)]
 LL | |
@@ -358,121 +342,91 @@ LL | | }
    | |_^
 
 error: `#[suggestion_part(...)]` attribute without `code = "..."`
-  --> $DIR/subdiagnostic-derive.rs:575:5
+  --> $DIR/subdiagnostic-derive.rs:577:5
    |
 LL |     #[suggestion_part]
    |     ^^^^^^^^^^^^^^^^^^
 
+error: `#[suggestion_part(...)]` attribute without `code = "..."`
+  --> $DIR/subdiagnostic-derive.rs:580:5
+   |
+LL |     #[suggestion_part()]
+   |     ^^^^^^^^^^^^^^^^^^^^
+
 error: `code` is the only valid nested attribute
-  --> $DIR/subdiagnostic-derive.rs:581:23
+  --> $DIR/subdiagnostic-derive.rs:583:23
    |
 LL |     #[suggestion_part(foo = "bar")]
    |                       ^^^
 
 error: the `#[suggestion_part(...)]` attribute can only be applied to fields of type `Span` or `MultiSpan`
-  --> $DIR/subdiagnostic-derive.rs:585:5
+  --> $DIR/subdiagnostic-derive.rs:588:5
    |
 LL |     #[suggestion_part(code = "...")]
    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 
 error: the `#[suggestion_part(...)]` attribute can only be applied to fields of type `Span` or `MultiSpan`
-  --> $DIR/subdiagnostic-derive.rs:588:5
+  --> $DIR/subdiagnostic-derive.rs:591:5
    |
 LL |     #[suggestion_part()]
    |     ^^^^^^^^^^^^^^^^^^^^
 
-error: unexpected end of input, unexpected token in nested attribute, expected ident
-  --> $DIR/subdiagnostic-derive.rs:578:23
-   |
-LL |     #[suggestion_part()]
-   |                       ^
-
-error: expected `,`
-  --> $DIR/subdiagnostic-derive.rs:581:27
-   |
-LL |     #[suggestion_part(foo = "bar")]
-   |                           ^
-
 error: specified multiple times
-  --> $DIR/subdiagnostic-derive.rs:596:37
+  --> $DIR/subdiagnostic-derive.rs:599:37
    |
 LL |     #[suggestion_part(code = "...", code = ",,,")]
    |                                     ^^^^
    |
 note: previously specified here
-  --> $DIR/subdiagnostic-derive.rs:596:23
+  --> $DIR/subdiagnostic-derive.rs:599:23
    |
 LL |     #[suggestion_part(code = "...", code = ",,,")]
    |                       ^^^^
 
 error: `#[applicability]` has no effect if all `#[suggestion]`/`#[multipart_suggestion]` attributes have a static `applicability = "..."`
-  --> $DIR/subdiagnostic-derive.rs:625:5
+  --> $DIR/subdiagnostic-derive.rs:628:5
    |
 LL |     #[applicability]
    |     ^^^^^^^^^^^^^^^^
 
 error: expected exactly one string literal for `code = ...`
-  --> $DIR/subdiagnostic-derive.rs:673:34
+  --> $DIR/subdiagnostic-derive.rs:676:34
    |
 LL |     #[suggestion_part(code("foo"))]
    |                                  ^
 
-error: unexpected token
-  --> $DIR/subdiagnostic-derive.rs:673:28
-   |
-LL |     #[suggestion_part(code("foo"))]
-   |                            ^^^^^
-
 error: expected exactly one string literal for `code = ...`
-  --> $DIR/subdiagnostic-derive.rs:683:41
+  --> $DIR/subdiagnostic-derive.rs:687:41
    |
 LL |     #[suggestion_part(code("foo", "bar"))]
    |                                         ^
 
-error: unexpected token
-  --> $DIR/subdiagnostic-derive.rs:683:28
-   |
-LL |     #[suggestion_part(code("foo", "bar"))]
-   |                            ^^^^^
-
 error: expected exactly one string literal for `code = ...`
-  --> $DIR/subdiagnostic-derive.rs:693:30
+  --> $DIR/subdiagnostic-derive.rs:698:30
    |
 LL |     #[suggestion_part(code(3))]
    |                              ^
 
-error: unexpected token
-  --> $DIR/subdiagnostic-derive.rs:693:28
-   |
-LL |     #[suggestion_part(code(3))]
-   |                            ^
-
 error: expected exactly one string literal for `code = ...`
-  --> $DIR/subdiagnostic-derive.rs:703:29
+  --> $DIR/subdiagnostic-derive.rs:709:29
    |
 LL |     #[suggestion_part(code())]
    |                             ^
 
-error: expected string literal
-  --> $DIR/subdiagnostic-derive.rs:715:30
-   |
-LL |     #[suggestion_part(code = 3)]
-   |                              ^
-
 error: specified multiple times
-  --> $DIR/subdiagnostic-derive.rs:757:1
+  --> $DIR/subdiagnostic-derive.rs:764:1
    |
 LL | #[suggestion(no_crate_example, code = "", style = "hidden", style = "normal")]
    | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    |
 note: previously specified here
-  --> $DIR/subdiagnostic-derive.rs:757:1
+  --> $DIR/subdiagnostic-derive.rs:764:1
    |
 LL | #[suggestion(no_crate_example, code = "", style = "hidden", style = "normal")]
    | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 
 error: `#[suggestion_hidden(...)]` is not a valid attribute
-  --> $DIR/subdiagnostic-derive.rs:766:1
+  --> $DIR/subdiagnostic-derive.rs:773:1
    |
 LL | #[suggestion_hidden(no_crate_example, code = "")]
    | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
@@ -480,7 +434,7 @@ LL | #[suggestion_hidden(no_crate_example, code = "")]
    = help: Use `#[suggestion(..., style = "hidden")]` instead
 
 error: `#[suggestion_hidden(...)]` is not a valid attribute
-  --> $DIR/subdiagnostic-derive.rs:774:1
+  --> $DIR/subdiagnostic-derive.rs:781:1
    |
 LL | #[suggestion_hidden(no_crate_example, code = "", style = "normal")]
    | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
@@ -488,7 +442,7 @@ LL | #[suggestion_hidden(no_crate_example, code = "", style = "normal")]
    = help: Use `#[suggestion(..., style = "hidden")]` instead
 
 error: invalid suggestion style
-  --> $DIR/subdiagnostic-derive.rs:782:51
+  --> $DIR/subdiagnostic-derive.rs:789:51
    |
 LL | #[suggestion(no_crate_example, code = "", style = "foo")]
    |                                                   ^^^^^
@@ -496,31 +450,25 @@ LL | #[suggestion(no_crate_example, code = "", style = "foo")]
    = help: valid styles are `normal`, `short`, `hidden`, `verbose` and `tool-only`
 
 error: expected `= "xxx"`
-  --> $DIR/subdiagnostic-derive.rs:790:49
+  --> $DIR/subdiagnostic-derive.rs:797:49
    |
 LL | #[suggestion(no_crate_example, code = "", style = 42)]
    |                                                 ^
 
 error: a diagnostic slug must be the first argument to the attribute
-  --> $DIR/subdiagnostic-derive.rs:798:48
+  --> $DIR/subdiagnostic-derive.rs:805:48
    |
 LL | #[suggestion(no_crate_example, code = "", style)]
    |                                                ^
 
 error: expected `= "xxx"`
-  --> $DIR/subdiagnostic-derive.rs:806:48
-   |
-LL | #[suggestion(no_crate_example, code = "", style("foo"))]
-   |                                                ^
-
-error: expected `,`
-  --> $DIR/subdiagnostic-derive.rs:806:48
+  --> $DIR/subdiagnostic-derive.rs:813:48
    |
 LL | #[suggestion(no_crate_example, code = "", style("foo"))]
    |                                                ^
 
 error: `#[primary_span]` is not a valid attribute
-  --> $DIR/subdiagnostic-derive.rs:818:5
+  --> $DIR/subdiagnostic-derive.rs:826:5
    |
 LL |     #[primary_span]
    |     ^^^^^^^^^^^^^^^
@@ -529,7 +477,7 @@ LL |     #[primary_span]
    = help: to create a suggestion with multiple spans, use `#[multipart_suggestion]` instead
 
 error: suggestion without `#[primary_span]` field
-  --> $DIR/subdiagnostic-derive.rs:815:1
+  --> $DIR/subdiagnostic-derive.rs:823:1
    |
 LL | / #[suggestion(no_crate_example, code = "")]
 LL | |
@@ -540,6 +488,54 @@ LL | |     sub: Vec<Span>,
 LL | | }
    | |_^
 
+error[E0433]: failed to resolve: maybe a missing crate `core`?
+  --> $DIR/subdiagnostic-derive.rs:97:9
+   |
+LL | #[label("...")]
+   |         ^^^^^ maybe a missing crate `core`?
+
+error[E0433]: failed to resolve: maybe a missing crate `core`?
+  --> $DIR/subdiagnostic-derive.rs:313:1
+   |
+LL | union AC {
+   | ^^^^^ maybe a missing crate `core`?
+
+error[E0433]: failed to resolve: maybe a missing crate `core`?
+  --> $DIR/subdiagnostic-derive.rs:583:27
+   |
+LL |     #[suggestion_part(foo = "bar")]
+   |                           ^ maybe a missing crate `core`?
+
+error[E0433]: failed to resolve: maybe a missing crate `core`?
+  --> $DIR/subdiagnostic-derive.rs:676:28
+   |
+LL |     #[suggestion_part(code("foo"))]
+   |                            ^^^^^ maybe a missing crate `core`?
+
+error[E0433]: failed to resolve: maybe a missing crate `core`?
+  --> $DIR/subdiagnostic-derive.rs:687:28
+   |
+LL |     #[suggestion_part(code("foo", "bar"))]
+   |                            ^^^^^ maybe a missing crate `core`?
+
+error[E0433]: failed to resolve: maybe a missing crate `core`?
+  --> $DIR/subdiagnostic-derive.rs:698:28
+   |
+LL |     #[suggestion_part(code(3))]
+   |                            ^ maybe a missing crate `core`?
+
+error[E0433]: failed to resolve: maybe a missing crate `core`?
+  --> $DIR/subdiagnostic-derive.rs:721:30
+   |
+LL |     #[suggestion_part(code = 3)]
+   |                              ^ maybe a missing crate `core`?
+
+error[E0433]: failed to resolve: maybe a missing crate `core`?
+  --> $DIR/subdiagnostic-derive.rs:813:48
+   |
+LL | #[suggestion(no_crate_example, code = "", style("foo"))]
+   |                                                ^ maybe a missing crate `core`?
+
 error: cannot find attribute `foo` in this scope
   --> $DIR/subdiagnostic-derive.rs:68:3
    |
@@ -547,61 +543,61 @@ LL | #[foo]
    |   ^^^
 
 error: cannot find attribute `foo` in this scope
-  --> $DIR/subdiagnostic-derive.rs:163:3
+  --> $DIR/subdiagnostic-derive.rs:164:3
    |
 LL | #[foo]
    |   ^^^
 
 error: cannot find attribute `bar` in this scope
-  --> $DIR/subdiagnostic-derive.rs:177:7
+  --> $DIR/subdiagnostic-derive.rs:178:7
    |
 LL |     #[bar]
    |       ^^^
 
 error: cannot find attribute `bar` in this scope
-  --> $DIR/subdiagnostic-derive.rs:189:7
+  --> $DIR/subdiagnostic-derive.rs:190:7
    |
 LL |     #[bar = "..."]
    |       ^^^
 
 error: cannot find attribute `bar` in this scope
-  --> $DIR/subdiagnostic-derive.rs:201:7
+  --> $DIR/subdiagnostic-derive.rs:202:7
    |
 LL |     #[bar = 4]
    |       ^^^
 
 error: cannot find attribute `bar` in this scope
-  --> $DIR/subdiagnostic-derive.rs:213:7
+  --> $DIR/subdiagnostic-derive.rs:214:7
    |
 LL |     #[bar("...")]
    |       ^^^
 
 error: cannot find attribute `bar` in this scope
-  --> $DIR/subdiagnostic-derive.rs:274:7
+  --> $DIR/subdiagnostic-derive.rs:275:7
    |
 LL |     #[bar]
    |       ^^^
 
 error: cannot find attribute `bar` in this scope
-  --> $DIR/subdiagnostic-derive.rs:285:7
+  --> $DIR/subdiagnostic-derive.rs:286:7
    |
 LL |     #[bar = "..."]
    |       ^^^
 
 error: cannot find attribute `bar` in this scope
-  --> $DIR/subdiagnostic-derive.rs:296:7
+  --> $DIR/subdiagnostic-derive.rs:297:7
    |
 LL |     #[bar("...")]
    |       ^^^
 
 error[E0425]: cannot find value `slug` in module `crate::fluent_generated`
-  --> $DIR/subdiagnostic-derive.rs:126:9
+  --> $DIR/subdiagnostic-derive.rs:127:9
    |
 LL | #[label(slug)]
    |         ^^^^ not found in `crate::fluent_generated`
 
 error[E0425]: cannot find value `__code_29` in this scope
-  --> $DIR/subdiagnostic-derive.rs:709:10
+  --> $DIR/subdiagnostic-derive.rs:715:10
    |
 LL | #[derive(Subdiagnostic)]
    |          ^^^^^^^^^^^^^ not found in this scope
@@ -610,4 +606,5 @@ LL | #[derive(Subdiagnostic)]
 
 error: aborting due to 86 previous errors
 
-For more information about this error, try `rustc --explain E0425`.
+Some errors have detailed explanations: E0425, E0433.
+For more information about an error, try `rustc --explain E0425`.