diff --git a/tests/ui-fulldeps/session-diagnostic/subdiagnostic-derive-inline.rs b/tests/ui-fulldeps/session-diagnostic/subdiagnostic-derive-inline.rs
new file mode 100644
index 000000000000..eaa681d40be5
--- /dev/null
+++ b/tests/ui-fulldeps/session-diagnostic/subdiagnostic-derive-inline.rs
@@ -0,0 +1,807 @@
+//@ check-fail
+// Tests error conditions for specifying inline subdiagnostics using #[derive(Subdiagnostic)]
+
+// The proc_macro2 crate handles spans differently when on beta/stable release rather than nightly,
+// changing the output of this test. Since Subdiagnostic is strictly internal to the compiler
+// the test is just ignored on stable and beta:
+//@ ignore-stage1
+//@ ignore-beta
+//@ ignore-stable
+
+#![feature(rustc_private)]
+#![crate_type = "lib"]
+
+extern crate rustc_errors;
+extern crate rustc_fluent_macro;
+extern crate rustc_macros;
+extern crate rustc_session;
+extern crate rustc_span;
+extern crate core;
+
+use rustc_errors::{Applicability, DiagMessage, SubdiagMessage};
+use rustc_macros::Subdiagnostic;
+use rustc_span::Span;
+
+#[derive(Subdiagnostic)]
+#[label("example message")]
+struct A {
+    #[primary_span]
+    span: Span,
+    var: String,
+}
+
+#[derive(Subdiagnostic)]
+enum B {
+    #[label("example message")]
+    A {
+        #[primary_span]
+        span: Span,
+        var: String,
+    },
+    #[label("example message")]
+    B {
+        #[primary_span]
+        span: Span,
+        var: String,
+    },
+}
+
+#[derive(Subdiagnostic)]
+#[label("example message")]
+//~^ ERROR label without `#[primary_span]` field
+struct C {
+    var: String,
+}
+
+#[derive(Subdiagnostic)]
+#[label]
+//~^ ERROR diagnostic slug must be first argument
+struct D {
+    #[primary_span]
+    span: Span,
+    var: String,
+}
+
+#[derive(Subdiagnostic)]
+#[foo]
+//~^ ERROR `#[foo]` is not a valid attribute
+//~^^ ERROR cannot find attribute `foo` in this scope
+struct E {
+    #[primary_span]
+    span: Span,
+    var: String,
+}
+
+#[derive(Subdiagnostic)]
+#[label = "..."]
+//~^ ERROR `#[label = ...]` is not a valid attribute
+struct F {
+    #[primary_span]
+    span: Span,
+    var: String,
+}
+
+#[derive(Subdiagnostic)]
+#[label(bug = "...")]
+//~^ ERROR no nested attribute expected here
+//~| ERROR diagnostic slug must be first argument
+struct G {
+    #[primary_span]
+    span: Span,
+    var: String,
+}
+
+#[derive(Subdiagnostic)]
+#[label(slug = 4)]
+//~^ ERROR no nested attribute expected here
+//~| ERROR diagnostic slug must be first argument
+struct J {
+    #[primary_span]
+    span: Span,
+    var: String,
+}
+
+#[derive(Subdiagnostic)]
+#[label(slug("..."))]
+//~^ ERROR no nested attribute expected here
+//~| ERROR diagnostic slug must be first argument
+struct K {
+    #[primary_span]
+    span: Span,
+    var: String,
+}
+
+#[derive(Subdiagnostic)]
+#[label()]
+//~^ ERROR diagnostic slug must be first argument of a `#[label(...)]` attribute
+struct M {
+    #[primary_span]
+    span: Span,
+    var: String,
+}
+
+#[derive(Subdiagnostic)]
+#[label("example message", code = "...")]
+//~^ ERROR no nested attribute expected here
+struct N {
+    #[primary_span]
+    span: Span,
+    var: String,
+}
+
+#[derive(Subdiagnostic)]
+#[label("example message", applicability = "machine-applicable")]
+//~^ ERROR no nested attribute expected here
+struct O {
+    #[primary_span]
+    span: Span,
+    var: String,
+}
+
+#[derive(Subdiagnostic)]
+#[foo]
+//~^ ERROR cannot find attribute `foo` in this scope
+//~^^ ERROR unsupported type attribute for subdiagnostic enum
+enum P {
+    #[label("example message")]
+    A {
+        #[primary_span]
+        span: Span,
+        var: String,
+    },
+}
+
+#[derive(Subdiagnostic)]
+enum Q {
+    #[bar]
+    //~^ ERROR `#[bar]` is not a valid attribute
+    //~^^ ERROR cannot find attribute `bar` in this scope
+    A {
+        #[primary_span]
+        span: Span,
+        var: String,
+    },
+}
+
+#[derive(Subdiagnostic)]
+enum R {
+    #[bar = "..."]
+    //~^ ERROR `#[bar = ...]` is not a valid attribute
+    //~^^ ERROR cannot find attribute `bar` in this scope
+    A {
+        #[primary_span]
+        span: Span,
+        var: String,
+    },
+}
+
+#[derive(Subdiagnostic)]
+enum S {
+    #[bar = 4]
+    //~^ ERROR `#[bar = ...]` is not a valid attribute
+    //~^^ ERROR cannot find attribute `bar` in this scope
+    A {
+        #[primary_span]
+        span: Span,
+        var: String,
+    },
+}
+
+#[derive(Subdiagnostic)]
+enum T {
+    #[bar("...")]
+    //~^ ERROR `#[bar(...)]` is not a valid attribute
+    //~^^ ERROR cannot find attribute `bar` in this scope
+    A {
+        #[primary_span]
+        span: Span,
+        var: String,
+    },
+}
+
+#[derive(Subdiagnostic)]
+enum U {
+    #[label(code = "...")]
+    //~^ ERROR diagnostic slug must be first argument of a `#[label(...)]` attribute
+    //~| ERROR no nested attribute expected here
+    A {
+        #[primary_span]
+        span: Span,
+        var: String,
+    },
+}
+
+#[derive(Subdiagnostic)]
+enum V {
+    #[label("example message")]
+    A {
+        #[primary_span]
+        span: Span,
+        var: String,
+    },
+    B {
+        #[primary_span]
+        span: Span,
+        var: String,
+    },
+}
+
+#[derive(Subdiagnostic)]
+#[label("example message")]
+//~^ ERROR label without `#[primary_span]` field
+struct W {
+    #[primary_span]
+    //~^ ERROR the `#[primary_span]` attribute can only be applied to fields of type `Span` or `MultiSpan`
+    span: String,
+}
+
+#[derive(Subdiagnostic)]
+#[label("example message")]
+struct X {
+    #[primary_span]
+    span: Span,
+    #[applicability]
+    //~^ ERROR `#[applicability]` is only valid on suggestions
+    applicability: Applicability,
+}
+
+#[derive(Subdiagnostic)]
+#[label("example message")]
+struct Y {
+    #[primary_span]
+    span: Span,
+    #[bar]
+    //~^ ERROR `#[bar]` is not a valid attribute
+    //~^^ ERROR cannot find attribute `bar` in this scope
+    bar: String,
+}
+
+#[derive(Subdiagnostic)]
+#[label("example message")]
+struct Z {
+    #[primary_span]
+    span: Span,
+    #[bar = "..."]
+    //~^ ERROR `#[bar = ...]` is not a valid attribute
+    //~^^ ERROR cannot find attribute `bar` in this scope
+    bar: String,
+}
+
+#[derive(Subdiagnostic)]
+#[label("example message")]
+struct AA {
+    #[primary_span]
+    span: Span,
+    #[bar("...")]
+    //~^ ERROR `#[bar(...)]` is not a valid attribute
+    //~^^ ERROR cannot find attribute `bar` in this scope
+    bar: String,
+}
+
+#[derive(Subdiagnostic)]
+#[label("example message")]
+struct AB {
+    #[primary_span]
+    span: Span,
+    #[skip_arg]
+    z: Z,
+}
+
+#[derive(Subdiagnostic)]
+union AC {
+    //~^ ERROR unexpected unsupported untagged union
+    span: u32,
+    b: u64,
+}
+
+#[derive(Subdiagnostic)]
+#[label("example message")]
+#[label("example message")]
+struct AD {
+    #[primary_span]
+    span: Span,
+}
+
+#[derive(Subdiagnostic)]
+#[label("example message", no_crate::example)]
+//~^ ERROR a diagnostic slug must be the first argument to the attribute
+struct AE {
+    #[primary_span]
+    span: Span,
+}
+
+#[derive(Subdiagnostic)]
+#[label("example message")]
+struct AF {
+    #[primary_span]
+    //~^ NOTE previously specified here
+    span_a: Span,
+    #[primary_span]
+    //~^ ERROR specified multiple times
+    span_b: Span,
+}
+
+#[derive(Subdiagnostic)]
+struct AG {
+    //~^ ERROR subdiagnostic kind not specified
+    #[primary_span]
+    span: Span,
+}
+
+#[derive(Subdiagnostic)]
+#[suggestion("example message", code = "...")]
+struct AH {
+    #[primary_span]
+    span: Span,
+    #[applicability]
+    applicability: Applicability,
+    var: String,
+}
+
+#[derive(Subdiagnostic)]
+enum AI {
+    #[suggestion("example message", code = "...")]
+    A {
+        #[primary_span]
+        span: Span,
+        #[applicability]
+        applicability: Applicability,
+        var: String,
+    },
+    #[suggestion("example message", code = "...")]
+    B {
+        #[primary_span]
+        span: Span,
+        #[applicability]
+        applicability: Applicability,
+        var: String,
+    },
+}
+
+#[derive(Subdiagnostic)]
+#[suggestion("example message", code = "...", code = "...")]
+//~^ ERROR specified multiple times
+//~^^ NOTE previously specified here
+struct AJ {
+    #[primary_span]
+    span: Span,
+    #[applicability]
+    applicability: Applicability,
+}
+
+#[derive(Subdiagnostic)]
+#[suggestion("example message", code = "...")]
+struct AK {
+    #[primary_span]
+    span: Span,
+    #[applicability]
+    //~^ NOTE previously specified here
+    applicability_a: Applicability,
+    #[applicability]
+    //~^ ERROR specified multiple times
+    applicability_b: Applicability,
+}
+
+#[derive(Subdiagnostic)]
+#[suggestion("example message", code = "...")]
+struct AL {
+    #[primary_span]
+    span: Span,
+    #[applicability]
+    //~^ ERROR the `#[applicability]` attribute can only be applied to fields of type `Applicability`
+    applicability: Span,
+}
+
+#[derive(Subdiagnostic)]
+#[suggestion("example message", code = "...")]
+struct AM {
+    #[primary_span]
+    span: Span,
+}
+
+#[derive(Subdiagnostic)]
+#[suggestion("example message")]
+//~^ ERROR suggestion without `code = "..."`
+struct AN {
+    #[primary_span]
+    span: Span,
+    #[applicability]
+    applicability: Applicability,
+}
+
+#[derive(Subdiagnostic)]
+#[suggestion("example message", code = "...", applicability = "foo")]
+//~^ ERROR invalid applicability
+struct AO {
+    #[primary_span]
+    span: Span,
+}
+
+#[derive(Subdiagnostic)]
+#[help("example message")]
+struct AP {
+    var: String,
+}
+
+#[derive(Subdiagnostic)]
+#[note("example message")]
+struct AQ;
+
+#[derive(Subdiagnostic)]
+#[suggestion("example message", code = "...")]
+//~^ ERROR suggestion without `#[primary_span]` field
+struct AR {
+    var: String,
+}
+
+#[derive(Subdiagnostic)]
+#[suggestion("example message", code = "...", applicability = "machine-applicable")]
+struct AS {
+    #[primary_span]
+    span: Span,
+}
+
+#[derive(Subdiagnostic)]
+#[label]
+//~^ ERROR unsupported type attribute for subdiagnostic enum
+enum AT {
+    #[label("example message")]
+    A {
+        #[primary_span]
+        span: Span,
+        var: String,
+    },
+}
+
+#[derive(Subdiagnostic)]
+#[suggestion("example message", code = "{var}", applicability = "machine-applicable")]
+struct AU {
+    #[primary_span]
+    span: Span,
+    var: String,
+}
+
+#[derive(Subdiagnostic)]
+#[suggestion("example message", code = "{var}", applicability = "machine-applicable")]
+//~^ ERROR `var` doesn't refer to a field on this type
+struct AV {
+    #[primary_span]
+    span: Span,
+}
+
+#[derive(Subdiagnostic)]
+enum AW {
+    #[suggestion("example message", code = "{var}", applicability = "machine-applicable")]
+    A {
+        #[primary_span]
+        span: Span,
+        var: String,
+    },
+}
+
+#[derive(Subdiagnostic)]
+enum AX {
+    #[suggestion("example message", code = "{var}", applicability = "machine-applicable")]
+    //~^ ERROR `var` doesn't refer to a field on this type
+    A {
+        #[primary_span]
+        span: Span,
+    },
+}
+
+#[derive(Subdiagnostic)]
+#[warning("example message")]
+struct AY {}
+
+#[derive(Subdiagnostic)]
+#[warning("example message")]
+struct AZ {
+    #[primary_span]
+    span: Span,
+}
+
+#[derive(Subdiagnostic)]
+#[suggestion("example message", code = "...")]
+//~^ ERROR suggestion without `#[primary_span]` field
+struct BA {
+    #[suggestion_part]
+    //~^ ERROR `#[suggestion_part]` is not a valid attribute
+    span: Span,
+    #[suggestion_part(code = "...")]
+    //~^ ERROR `#[suggestion_part(...)]` is not a valid attribute
+    span2: Span,
+    #[applicability]
+    applicability: Applicability,
+    var: String,
+}
+
+#[derive(Subdiagnostic)]
+#[multipart_suggestion("example message", code = "...", applicability = "machine-applicable")]
+//~^ ERROR multipart suggestion without any `#[suggestion_part(...)]` fields
+//~| ERROR invalid nested attribute
+struct BBa {
+    var: String,
+}
+
+#[derive(Subdiagnostic)]
+#[multipart_suggestion("example message", applicability = "machine-applicable")]
+struct BBb {
+    #[suggestion_part]
+    //~^ ERROR `#[suggestion_part(...)]` attribute without `code = "..."`
+    span1: Span,
+}
+
+#[derive(Subdiagnostic)]
+#[multipart_suggestion("example message", applicability = "machine-applicable")]
+struct BBc {
+    #[suggestion_part()]
+    //~^ ERROR `#[suggestion_part(...)]` attribute without `code = "..."`
+    span1: Span,
+}
+
+#[derive(Subdiagnostic)]
+#[multipart_suggestion("example message")]
+//~^ ERROR multipart suggestion without any `#[suggestion_part(...)]` fields
+struct BC {
+    #[primary_span]
+    //~^ ERROR `#[primary_span]` is not a valid attribute
+    span: Span,
+}
+
+#[derive(Subdiagnostic)]
+#[multipart_suggestion("example message")]
+struct BD {
+    #[suggestion_part]
+    //~^ ERROR `#[suggestion_part(...)]` attribute without `code = "..."`
+    span1: Span,
+    #[suggestion_part()]
+    //~^ ERROR `#[suggestion_part(...)]` attribute without `code = "..."`
+    span2: Span,
+    #[suggestion_part(foo = "bar")]
+    //~^ ERROR `code` is the only valid nested attribute
+    //~| ERROR expected `,`
+    span4: Span,
+    #[suggestion_part(code = "...")]
+    //~^ ERROR the `#[suggestion_part(...)]` attribute can only be applied to fields of type `Span` or `MultiSpan`
+    s1: String,
+    #[suggestion_part()]
+    //~^ ERROR the `#[suggestion_part(...)]` attribute can only be applied to fields of type `Span` or `MultiSpan`
+    s2: String,
+}
+
+#[derive(Subdiagnostic)]
+#[multipart_suggestion("example message", applicability = "machine-applicable")]
+struct BE {
+    #[suggestion_part(code = "...", code = ",,,")]
+    //~^ ERROR specified multiple times
+    //~| NOTE previously specified here
+    span: Span,
+}
+
+#[derive(Subdiagnostic)]
+#[multipart_suggestion("example message", applicability = "machine-applicable")]
+struct BF {
+    #[suggestion_part(code = "(")]
+    first: Span,
+    #[suggestion_part(code = ")")]
+    second: Span,
+}
+
+#[derive(Subdiagnostic)]
+#[multipart_suggestion("example message")]
+struct BG {
+    #[applicability]
+    appl: Applicability,
+    #[suggestion_part(code = "(")]
+    first: Span,
+    #[suggestion_part(code = ")")]
+    second: Span,
+}
+
+#[derive(Subdiagnostic)]
+#[multipart_suggestion("example message", applicability = "machine-applicable")]
+struct BH {
+    #[applicability]
+    //~^ ERROR `#[applicability]` has no effect
+    appl: Applicability,
+    #[suggestion_part(code = "(")]
+    first: Span,
+    #[suggestion_part(code = ")")]
+    second: Span,
+}
+
+#[derive(Subdiagnostic)]
+#[multipart_suggestion("example message", applicability = "machine-applicable")]
+struct BI {
+    #[suggestion_part(code = "")]
+    spans: Vec<Span>,
+}
+
+#[derive(Subdiagnostic)]
+#[label("example message")]
+struct BJ {
+    #[primary_span]
+    span: Span,
+    r#type: String,
+}
+
+/// with a doc comment on the type..
+#[derive(Subdiagnostic)]
+#[label("example message")]
+struct BK {
+    /// ..and the field
+    #[primary_span]
+    span: Span,
+}
+
+/// with a doc comment on the type..
+#[derive(Subdiagnostic)]
+enum BL {
+    /// ..and the variant..
+    #[label("example message")]
+    Foo {
+        /// ..and the field
+        #[primary_span]
+        span: Span,
+    },
+}
+
+#[derive(Subdiagnostic)]
+#[multipart_suggestion("example message")]
+struct BM {
+    #[suggestion_part(code("foo"))]
+    //~^ ERROR expected exactly one string literal for `code = ...`
+    //~| ERROR unexpected token, expected `)`
+    span: Span,
+    r#type: String,
+}
+
+#[derive(Subdiagnostic)]
+#[multipart_suggestion("example message")]
+struct BN {
+    #[suggestion_part(code("foo", "bar"))]
+    //~^ ERROR expected exactly one string literal for `code = ...`
+    //~| ERROR unexpected token, expected `)`
+    span: Span,
+    r#type: String,
+}
+
+#[derive(Subdiagnostic)]
+#[multipart_suggestion("example message")]
+struct BO {
+    #[suggestion_part(code(3))]
+    //~^ ERROR expected exactly one string literal for `code = ...`
+    //~| ERROR unexpected token, expected `)`
+    span: Span,
+    r#type: String,
+}
+
+#[derive(Subdiagnostic)]
+#[multipart_suggestion("example message")]
+struct BP {
+    #[suggestion_part(code())]
+    //~^ ERROR expected exactly one string literal for `code = ...`
+    span: Span,
+    r#type: String,
+}
+
+#[derive(Subdiagnostic)]
+#[multipart_suggestion("example message")]
+struct BQ {
+    #[suggestion_part(code = 3)]
+    //~^ ERROR expected string literal
+    span: Span,
+    r#type: String,
+}
+
+#[derive(Subdiagnostic)]
+#[suggestion("example message", code = "")]
+struct SuggestionStyleDefault {
+    #[primary_span]
+    sub: Span,
+}
+
+#[derive(Subdiagnostic)]
+#[suggestion("example message", code = "", style = "short")]
+struct SuggestionStyleShort {
+    #[primary_span]
+    sub: Span,
+}
+
+#[derive(Subdiagnostic)]
+#[suggestion("example message", code = "", style = "hidden")]
+struct SuggestionStyleHidden {
+    #[primary_span]
+    sub: Span,
+}
+
+#[derive(Subdiagnostic)]
+#[suggestion("example message", code = "", style = "verbose")]
+struct SuggestionStyleVerbose {
+    #[primary_span]
+    sub: Span,
+}
+
+#[derive(Subdiagnostic)]
+#[suggestion("example message", code = "", style = "tool-only")]
+struct SuggestionStyleToolOnly {
+    #[primary_span]
+    sub: Span,
+}
+
+#[derive(Subdiagnostic)]
+#[suggestion("example message", code = "", style = "hidden", style = "normal")]
+//~^ ERROR specified multiple times
+//~| NOTE previously specified here
+struct SuggestionStyleTwice {
+    #[primary_span]
+    sub: Span,
+}
+
+#[derive(Subdiagnostic)]
+#[suggestion_hidden("example message", code = "")]
+//~^ ERROR #[suggestion_hidden(...)]` is not a valid attribute
+struct SuggestionStyleOldSyntax {
+    #[primary_span]
+    sub: Span,
+}
+
+#[derive(Subdiagnostic)]
+#[suggestion_hidden("example message", code = "", style = "normal")]
+//~^ ERROR #[suggestion_hidden(...)]` is not a valid attribute
+struct SuggestionStyleOldAndNewSyntax {
+    #[primary_span]
+    sub: Span,
+}
+
+#[derive(Subdiagnostic)]
+#[suggestion("example message", code = "", style = "foo")]
+//~^ ERROR invalid suggestion style
+struct SuggestionStyleInvalid1 {
+    #[primary_span]
+    sub: Span,
+}
+
+#[derive(Subdiagnostic)]
+#[suggestion("example message", code = "", style = 42)]
+//~^ ERROR expected string literal
+struct SuggestionStyleInvalid2 {
+    #[primary_span]
+    sub: Span,
+}
+
+#[derive(Subdiagnostic)]
+#[suggestion("example message", code = "", style)]
+//~^ ERROR a diagnostic slug must be the first argument to the attribute
+struct SuggestionStyleInvalid3 {
+    #[primary_span]
+    sub: Span,
+}
+
+#[derive(Subdiagnostic)]
+#[suggestion("example message", code = "", style("foo"))]
+//~^ ERROR expected `=`
+struct SuggestionStyleInvalid4 {
+    #[primary_span]
+    sub: Span,
+}
+
+#[derive(Subdiagnostic)]
+#[suggestion("example message", code = "")]
+//~^ ERROR suggestion without `#[primary_span]` field
+struct PrimarySpanOnVec {
+    #[primary_span]
+    //~^ ERROR `#[primary_span]` is not a valid attribute
+    //~| NOTE there must be exactly one primary span
+    sub: Vec<Span>,
+}
+
+#[derive(Subdiagnostic)]
+struct NestedParent {
+    #[subdiagnostic]
+    single_sub: A,
+    #[subdiagnostic]
+    option_sub: Option<A>,
+    #[subdiagnostic]
+    vec_sub: Vec<A>,
+}
diff --git a/tests/ui-fulldeps/session-diagnostic/subdiagnostic-derive-inline.stderr b/tests/ui-fulldeps/session-diagnostic/subdiagnostic-derive-inline.stderr
new file mode 100644
index 000000000000..11753b949bc7
--- /dev/null
+++ b/tests/ui-fulldeps/session-diagnostic/subdiagnostic-derive-inline.stderr
@@ -0,0 +1,549 @@
+error: derive(Diagnostic): label without `#[primary_span]` field
+  --> $DIR/subdiagnostic-derive-inline.rs:50:1
+   |
+LL | #[label("example message")]
+   | ^
+
+error: derive(Diagnostic): diagnostic slug must be first argument of a `#[label(...)]` attribute
+  --> $DIR/subdiagnostic-derive-inline.rs:57:1
+   |
+LL | #[label]
+   | ^
+
+error: derive(Diagnostic): `#[foo]` is not a valid attribute
+  --> $DIR/subdiagnostic-derive-inline.rs:66:1
+   |
+LL | #[foo]
+   | ^
+
+error: derive(Diagnostic): `#[label = ...]` is not a valid attribute
+  --> $DIR/subdiagnostic-derive-inline.rs:76:1
+   |
+LL | #[label = "..."]
+   | ^
+
+error: derive(Diagnostic): no nested attribute expected here
+  --> $DIR/subdiagnostic-derive-inline.rs:85:9
+   |
+LL | #[label(bug = "...")]
+   |         ^^^
+
+error: derive(Diagnostic): diagnostic slug must be first argument of a `#[label(...)]` attribute
+  --> $DIR/subdiagnostic-derive-inline.rs:85:1
+   |
+LL | #[label(bug = "...")]
+   | ^
+
+error: derive(Diagnostic): no nested attribute expected here
+  --> $DIR/subdiagnostic-derive-inline.rs:95:9
+   |
+LL | #[label(slug = 4)]
+   |         ^^^^
+
+error: derive(Diagnostic): diagnostic slug must be first argument of a `#[label(...)]` attribute
+  --> $DIR/subdiagnostic-derive-inline.rs:95:1
+   |
+LL | #[label(slug = 4)]
+   | ^
+
+error: derive(Diagnostic): no nested attribute expected here
+  --> $DIR/subdiagnostic-derive-inline.rs:105:9
+   |
+LL | #[label(slug("..."))]
+   |         ^^^^
+
+error: derive(Diagnostic): diagnostic slug must be first argument of a `#[label(...)]` attribute
+  --> $DIR/subdiagnostic-derive-inline.rs:105:1
+   |
+LL | #[label(slug("..."))]
+   | ^
+
+error: derive(Diagnostic): diagnostic slug must be first argument of a `#[label(...)]` attribute
+  --> $DIR/subdiagnostic-derive-inline.rs:115:1
+   |
+LL | #[label()]
+   | ^
+
+error: derive(Diagnostic): no nested attribute expected here
+  --> $DIR/subdiagnostic-derive-inline.rs:124:28
+   |
+LL | #[label("example message", code = "...")]
+   |                            ^^^^
+
+error: derive(Diagnostic): no nested attribute expected here
+  --> $DIR/subdiagnostic-derive-inline.rs:133:28
+   |
+LL | #[label("example message", applicability = "machine-applicable")]
+   |                            ^^^^^^^^^^^^^
+
+error: derive(Diagnostic): unsupported type attribute for subdiagnostic enum
+  --> $DIR/subdiagnostic-derive-inline.rs:142:1
+   |
+LL | #[foo]
+   | ^
+
+error: derive(Diagnostic): `#[bar]` is not a valid attribute
+  --> $DIR/subdiagnostic-derive-inline.rs:156:5
+   |
+LL |     #[bar]
+   |     ^
+
+error: derive(Diagnostic): `#[bar = ...]` is not a valid attribute
+  --> $DIR/subdiagnostic-derive-inline.rs:168:5
+   |
+LL |     #[bar = "..."]
+   |     ^
+
+error: derive(Diagnostic): `#[bar = ...]` is not a valid attribute
+  --> $DIR/subdiagnostic-derive-inline.rs:180:5
+   |
+LL |     #[bar = 4]
+   |     ^
+
+error: derive(Diagnostic): `#[bar(...)]` is not a valid attribute
+  --> $DIR/subdiagnostic-derive-inline.rs:192:5
+   |
+LL |     #[bar("...")]
+   |     ^
+
+error: derive(Diagnostic): no nested attribute expected here
+  --> $DIR/subdiagnostic-derive-inline.rs:204:13
+   |
+LL |     #[label(code = "...")]
+   |             ^^^^
+
+error: derive(Diagnostic): diagnostic slug must be first argument of a `#[label(...)]` attribute
+  --> $DIR/subdiagnostic-derive-inline.rs:204:5
+   |
+LL |     #[label(code = "...")]
+   |     ^
+
+error: derive(Diagnostic): the `#[primary_span]` attribute can only be applied to fields of type `Span` or `MultiSpan`
+  --> $DIR/subdiagnostic-derive-inline.rs:233:5
+   |
+LL |     #[primary_span]
+   |     ^
+
+error: derive(Diagnostic): label without `#[primary_span]` field
+  --> $DIR/subdiagnostic-derive-inline.rs:230:1
+   |
+LL | #[label("example message")]
+   | ^
+
+error: derive(Diagnostic): `#[applicability]` is only valid on suggestions
+  --> $DIR/subdiagnostic-derive-inline.rs:243:5
+   |
+LL |     #[applicability]
+   |     ^
+
+error: derive(Diagnostic): `#[bar]` is not a valid attribute
+  --> $DIR/subdiagnostic-derive-inline.rs:253:5
+   |
+LL |     #[bar]
+   |     ^
+   |
+   = help: only `primary_span`, `applicability` and `skip_arg` are valid field attributes
+
+error: derive(Diagnostic): `#[bar = ...]` is not a valid attribute
+  --> $DIR/subdiagnostic-derive-inline.rs:264:5
+   |
+LL |     #[bar = "..."]
+   |     ^
+
+error: derive(Diagnostic): `#[bar(...)]` is not a valid attribute
+  --> $DIR/subdiagnostic-derive-inline.rs:275:5
+   |
+LL |     #[bar("...")]
+   |     ^
+   |
+   = help: only `primary_span`, `applicability` and `skip_arg` are valid field attributes
+
+error: unexpected unsupported untagged union
+  --> $DIR/subdiagnostic-derive-inline.rs:291:1
+   |
+LL | / union AC {
+LL | |
+LL | |     span: u32,
+LL | |     b: u64,
+LL | | }
+   | |_^
+
+error: derive(Diagnostic): a diagnostic slug must be the first argument to the attribute
+  --> $DIR/subdiagnostic-derive-inline.rs:306:28
+   |
+LL | #[label("example message", no_crate::example)]
+   |                            ^^^^^^^^
+
+error: derive(Diagnostic): attribute specified multiple times
+  --> $DIR/subdiagnostic-derive-inline.rs:319:5
+   |
+LL |     #[primary_span]
+   |     ^
+   |
+note: previously specified here
+  --> $DIR/subdiagnostic-derive-inline.rs:316:5
+   |
+LL |     #[primary_span]
+   |     ^
+
+error: derive(Diagnostic): subdiagnostic kind not specified
+  --> $DIR/subdiagnostic-derive-inline.rs:325:8
+   |
+LL | struct AG {
+   |        ^^
+
+error: derive(Diagnostic): attribute specified multiple times
+  --> $DIR/subdiagnostic-derive-inline.rs:362:47
+   |
+LL | #[suggestion("example message", code = "...", code = "...")]
+   |                                               ^^^^
+   |
+note: previously specified here
+  --> $DIR/subdiagnostic-derive-inline.rs:362:33
+   |
+LL | #[suggestion("example message", code = "...", code = "...")]
+   |                                 ^^^^
+
+error: derive(Diagnostic): attribute specified multiple times
+  --> $DIR/subdiagnostic-derive-inline.rs:380:5
+   |
+LL |     #[applicability]
+   |     ^
+   |
+note: previously specified here
+  --> $DIR/subdiagnostic-derive-inline.rs:377:5
+   |
+LL |     #[applicability]
+   |     ^
+
+error: derive(Diagnostic): the `#[applicability]` attribute can only be applied to fields of type `Applicability`
+  --> $DIR/subdiagnostic-derive-inline.rs:390:5
+   |
+LL |     #[applicability]
+   |     ^
+
+error: derive(Diagnostic): suggestion without `code = "..."`
+  --> $DIR/subdiagnostic-derive-inline.rs:403:1
+   |
+LL | #[suggestion("example message")]
+   | ^
+
+error: derive(Diagnostic): invalid applicability
+  --> $DIR/subdiagnostic-derive-inline.rs:413:63
+   |
+LL | #[suggestion("example message", code = "...", applicability = "foo")]
+   |                                                               ^^^^^
+
+error: derive(Diagnostic): suggestion without `#[primary_span]` field
+  --> $DIR/subdiagnostic-derive-inline.rs:431:1
+   |
+LL | #[suggestion("example message", code = "...")]
+   | ^
+
+error: derive(Diagnostic): unsupported type attribute for subdiagnostic enum
+  --> $DIR/subdiagnostic-derive-inline.rs:445:1
+   |
+LL | #[label]
+   | ^
+
+error: derive(Diagnostic): `var` doesn't refer to a field on this type
+  --> $DIR/subdiagnostic-derive-inline.rs:465:40
+   |
+LL | #[suggestion("example message", code = "{var}", applicability = "machine-applicable")]
+   |                                        ^^^^^^^
+
+error: derive(Diagnostic): `var` doesn't refer to a field on this type
+  --> $DIR/subdiagnostic-derive-inline.rs:484:44
+   |
+LL |     #[suggestion("example message", code = "{var}", applicability = "machine-applicable")]
+   |                                            ^^^^^^^
+
+error: derive(Diagnostic): `#[suggestion_part]` is not a valid attribute
+  --> $DIR/subdiagnostic-derive-inline.rs:507:5
+   |
+LL |     #[suggestion_part]
+   |     ^
+   |
+   = help: `#[suggestion_part(...)]` is only valid in multipart suggestions, use `#[primary_span]` instead
+
+error: derive(Diagnostic): `#[suggestion_part(...)]` is not a valid attribute
+  --> $DIR/subdiagnostic-derive-inline.rs:510:5
+   |
+LL |     #[suggestion_part(code = "...")]
+   |     ^
+   |
+   = help: `#[suggestion_part(...)]` is only valid in multipart suggestions
+
+error: derive(Diagnostic): suggestion without `#[primary_span]` field
+  --> $DIR/subdiagnostic-derive-inline.rs:504:1
+   |
+LL | #[suggestion("example message", code = "...")]
+   | ^
+
+error: derive(Diagnostic): invalid nested attribute
+  --> $DIR/subdiagnostic-derive-inline.rs:519:43
+   |
+LL | #[multipart_suggestion("example message", code = "...", applicability = "machine-applicable")]
+   |                                           ^^^^
+   |
+   = help: only `style` and `applicability` are valid nested attributes
+
+error: derive(Diagnostic): multipart suggestion without any `#[suggestion_part(...)]` fields
+  --> $DIR/subdiagnostic-derive-inline.rs:519:1
+   |
+LL | #[multipart_suggestion("example message", code = "...", applicability = "machine-applicable")]
+   | ^
+
+error: derive(Diagnostic): `#[suggestion_part(...)]` attribute without `code = "..."`
+  --> $DIR/subdiagnostic-derive-inline.rs:529:5
+   |
+LL |     #[suggestion_part]
+   |     ^
+
+error: derive(Diagnostic): `#[suggestion_part(...)]` attribute without `code = "..."`
+  --> $DIR/subdiagnostic-derive-inline.rs:537:5
+   |
+LL |     #[suggestion_part()]
+   |     ^
+
+error: derive(Diagnostic): `#[primary_span]` is not a valid attribute
+  --> $DIR/subdiagnostic-derive-inline.rs:546:5
+   |
+LL |     #[primary_span]
+   |     ^
+   |
+   = help: multipart suggestions use one or more `#[suggestion_part]`s rather than one `#[primary_span]`
+
+error: derive(Diagnostic): multipart suggestion without any `#[suggestion_part(...)]` fields
+  --> $DIR/subdiagnostic-derive-inline.rs:543:1
+   |
+LL | #[multipart_suggestion("example message")]
+   | ^
+
+error: derive(Diagnostic): `#[suggestion_part(...)]` attribute without `code = "..."`
+  --> $DIR/subdiagnostic-derive-inline.rs:554:5
+   |
+LL |     #[suggestion_part]
+   |     ^
+
+error: derive(Diagnostic): `#[suggestion_part(...)]` attribute without `code = "..."`
+  --> $DIR/subdiagnostic-derive-inline.rs:557:5
+   |
+LL |     #[suggestion_part()]
+   |     ^
+
+error: derive(Diagnostic): `code` is the only valid nested attribute
+  --> $DIR/subdiagnostic-derive-inline.rs:560:23
+   |
+LL |     #[suggestion_part(foo = "bar")]
+   |                       ^^^
+
+error: derive(Diagnostic): the `#[suggestion_part(...)]` attribute can only be applied to fields of type `Span` or `MultiSpan`
+  --> $DIR/subdiagnostic-derive-inline.rs:564:5
+   |
+LL |     #[suggestion_part(code = "...")]
+   |     ^
+
+error: derive(Diagnostic): the `#[suggestion_part(...)]` attribute can only be applied to fields of type `Span` or `MultiSpan`
+  --> $DIR/subdiagnostic-derive-inline.rs:567:5
+   |
+LL |     #[suggestion_part()]
+   |     ^
+
+error: expected `,`
+  --> $DIR/subdiagnostic-derive-inline.rs:560:27
+   |
+LL |     #[suggestion_part(foo = "bar")]
+   |                           ^
+
+error: derive(Diagnostic): attribute specified multiple times
+  --> $DIR/subdiagnostic-derive-inline.rs:575:37
+   |
+LL |     #[suggestion_part(code = "...", code = ",,,")]
+   |                                     ^^^^
+   |
+note: previously specified here
+  --> $DIR/subdiagnostic-derive-inline.rs:575:23
+   |
+LL |     #[suggestion_part(code = "...", code = ",,,")]
+   |                       ^^^^
+
+error: derive(Diagnostic): `#[applicability]` has no effect if all `#[suggestion]`/`#[multipart_suggestion]` attributes have a static `applicability = "..."`
+  --> $DIR/subdiagnostic-derive-inline.rs:604:5
+   |
+LL |     #[applicability]
+   |     ^
+
+error: derive(Diagnostic): expected exactly one string literal for `code = ...`
+  --> $DIR/subdiagnostic-derive-inline.rs:652:28
+   |
+LL |     #[suggestion_part(code("foo"))]
+   |                            ^^^^^
+
+error: unexpected token, expected `)`
+  --> $DIR/subdiagnostic-derive-inline.rs:652:28
+   |
+LL |     #[suggestion_part(code("foo"))]
+   |                            ^^^^^
+
+error: derive(Diagnostic): expected exactly one string literal for `code = ...`
+  --> $DIR/subdiagnostic-derive-inline.rs:662:28
+   |
+LL |     #[suggestion_part(code("foo", "bar"))]
+   |                            ^^^^^
+
+error: unexpected token, expected `)`
+  --> $DIR/subdiagnostic-derive-inline.rs:662:28
+   |
+LL |     #[suggestion_part(code("foo", "bar"))]
+   |                            ^^^^^
+
+error: derive(Diagnostic): expected exactly one string literal for `code = ...`
+  --> $DIR/subdiagnostic-derive-inline.rs:672:28
+   |
+LL |     #[suggestion_part(code(3))]
+   |                            ^
+
+error: unexpected token, expected `)`
+  --> $DIR/subdiagnostic-derive-inline.rs:672:28
+   |
+LL |     #[suggestion_part(code(3))]
+   |                            ^
+
+error: derive(Diagnostic): expected exactly one string literal for `code = ...`
+  --> $DIR/subdiagnostic-derive-inline.rs:682:28
+   |
+LL |     #[suggestion_part(code())]
+   |                            ^
+
+error: expected string literal
+  --> $DIR/subdiagnostic-derive-inline.rs:691:30
+   |
+LL |     #[suggestion_part(code = 3)]
+   |                              ^
+
+error: derive(Diagnostic): attribute specified multiple times
+  --> $DIR/subdiagnostic-derive-inline.rs:733:1
+   |
+LL | #[suggestion("example message", code = "", style = "hidden", style = "normal")]
+   | ^
+   |
+note: previously specified here
+  --> $DIR/subdiagnostic-derive-inline.rs:733:1
+   |
+LL | #[suggestion("example message", code = "", style = "hidden", style = "normal")]
+   | ^
+
+error: derive(Diagnostic): `#[suggestion_hidden(...)]` is not a valid attribute
+  --> $DIR/subdiagnostic-derive-inline.rs:742:1
+   |
+LL | #[suggestion_hidden("example message", code = "")]
+   | ^
+   |
+   = help: Use `#[suggestion(..., style = "hidden")]` instead
+
+error: derive(Diagnostic): `#[suggestion_hidden(...)]` is not a valid attribute
+  --> $DIR/subdiagnostic-derive-inline.rs:750:1
+   |
+LL | #[suggestion_hidden("example message", code = "", style = "normal")]
+   | ^
+   |
+   = help: Use `#[suggestion(..., style = "hidden")]` instead
+
+error: derive(Diagnostic): invalid suggestion style
+  --> $DIR/subdiagnostic-derive-inline.rs:758:52
+   |
+LL | #[suggestion("example message", code = "", style = "foo")]
+   |                                                    ^^^^^
+   |
+   = help: valid styles are `normal`, `short`, `hidden`, `verbose` and `tool-only`
+
+error: expected string literal
+  --> $DIR/subdiagnostic-derive-inline.rs:766:52
+   |
+LL | #[suggestion("example message", code = "", style = 42)]
+   |                                                    ^^
+
+error: derive(Diagnostic): a diagnostic slug must be the first argument to the attribute
+  --> $DIR/subdiagnostic-derive-inline.rs:774:44
+   |
+LL | #[suggestion("example message", code = "", style)]
+   |                                            ^^^^^
+
+error: expected `=`
+  --> $DIR/subdiagnostic-derive-inline.rs:782:49
+   |
+LL | #[suggestion("example message", code = "", style("foo"))]
+   |                                                 ^
+
+error: derive(Diagnostic): `#[primary_span]` is not a valid attribute
+  --> $DIR/subdiagnostic-derive-inline.rs:793:5
+   |
+LL |     #[primary_span]
+   |     ^
+   |
+   = note: there must be exactly one primary span
+   = help: to create a suggestion with multiple spans, use `#[multipart_suggestion]` instead
+
+error: derive(Diagnostic): suggestion without `#[primary_span]` field
+  --> $DIR/subdiagnostic-derive-inline.rs:790:1
+   |
+LL | #[suggestion("example message", code = "")]
+   | ^
+
+error: cannot find attribute `foo` in this scope
+  --> $DIR/subdiagnostic-derive-inline.rs:66:3
+   |
+LL | #[foo]
+   |   ^^^
+
+error: cannot find attribute `foo` in this scope
+  --> $DIR/subdiagnostic-derive-inline.rs:142:3
+   |
+LL | #[foo]
+   |   ^^^
+
+error: cannot find attribute `bar` in this scope
+  --> $DIR/subdiagnostic-derive-inline.rs:156:7
+   |
+LL |     #[bar]
+   |       ^^^
+
+error: cannot find attribute `bar` in this scope
+  --> $DIR/subdiagnostic-derive-inline.rs:168:7
+   |
+LL |     #[bar = "..."]
+   |       ^^^
+
+error: cannot find attribute `bar` in this scope
+  --> $DIR/subdiagnostic-derive-inline.rs:180:7
+   |
+LL |     #[bar = 4]
+   |       ^^^
+
+error: cannot find attribute `bar` in this scope
+  --> $DIR/subdiagnostic-derive-inline.rs:192:7
+   |
+LL |     #[bar("...")]
+   |       ^^^
+
+error: cannot find attribute `bar` in this scope
+  --> $DIR/subdiagnostic-derive-inline.rs:253:7
+   |
+LL |     #[bar]
+   |       ^^^
+
+error: cannot find attribute `bar` in this scope
+  --> $DIR/subdiagnostic-derive-inline.rs:264:7
+   |
+LL |     #[bar = "..."]
+   |       ^^^
+
+error: cannot find attribute `bar` in this scope
+  --> $DIR/subdiagnostic-derive-inline.rs:275:7
+   |
+LL |     #[bar("...")]
+   |       ^^^
+
+error: aborting due to 82 previous errors
+
diff --git a/tests/ui-fulldeps/session-diagnostic/subdiagnostic-derive.rs b/tests/ui-fulldeps/session-diagnostic/subdiagnostic-derive.rs
index b2e7b4c61daa..c06ea451b9bf 100644
--- a/tests/ui-fulldeps/session-diagnostic/subdiagnostic-derive.rs
+++ b/tests/ui-fulldeps/session-diagnostic/subdiagnostic-derive.rs
@@ -93,15 +93,6 @@ struct G {
     var: String,
 }
 
-#[derive(Subdiagnostic)]
-#[label("...")]
-//~^ ERROR expected identifier
-struct H {
-    #[primary_span]
-    span: Span,
-    var: String,
-}
-
 #[derive(Subdiagnostic)]
 #[label(slug = 4)]
 //~^ ERROR no nested attribute expected here
diff --git a/tests/ui-fulldeps/session-diagnostic/subdiagnostic-derive.stderr b/tests/ui-fulldeps/session-diagnostic/subdiagnostic-derive.stderr
index 63634741e934..9f18f7ffabcc 100644
--- a/tests/ui-fulldeps/session-diagnostic/subdiagnostic-derive.stderr
+++ b/tests/ui-fulldeps/session-diagnostic/subdiagnostic-derive.stderr
@@ -34,116 +34,110 @@ error: derive(Diagnostic): diagnostic slug must be first argument of a `#[label(
 LL | #[label(bug = "...")]
    | ^
 
-error: expected identifier
+error: derive(Diagnostic): no nested attribute expected here
   --> $DIR/subdiagnostic-derive.rs:97:9
    |
-LL | #[label("...")]
-   |         ^^^^^
-
-error: derive(Diagnostic): no nested attribute expected here
-  --> $DIR/subdiagnostic-derive.rs:106:9
-   |
 LL | #[label(slug = 4)]
    |         ^^^^
 
 error: derive(Diagnostic): diagnostic slug must be first argument of a `#[label(...)]` attribute
-  --> $DIR/subdiagnostic-derive.rs:106:1
+  --> $DIR/subdiagnostic-derive.rs:97:1
    |
 LL | #[label(slug = 4)]
    | ^
 
 error: derive(Diagnostic): no nested attribute expected here
-  --> $DIR/subdiagnostic-derive.rs:116:9
+  --> $DIR/subdiagnostic-derive.rs:107:9
    |
 LL | #[label(slug("..."))]
    |         ^^^^
 
 error: derive(Diagnostic): diagnostic slug must be first argument of a `#[label(...)]` attribute
-  --> $DIR/subdiagnostic-derive.rs:116:1
+  --> $DIR/subdiagnostic-derive.rs:107:1
    |
 LL | #[label(slug("..."))]
    | ^
 
 error: derive(Diagnostic): diagnostic slug must be first argument of a `#[label(...)]` attribute
-  --> $DIR/subdiagnostic-derive.rs:126:1
+  --> $DIR/subdiagnostic-derive.rs:117:1
    |
 LL | #[label()]
    | ^
 
 error: derive(Diagnostic): no nested attribute expected here
-  --> $DIR/subdiagnostic-derive.rs:135:27
+  --> $DIR/subdiagnostic-derive.rs:126:27
    |
 LL | #[label(no_crate_example, code = "...")]
    |                           ^^^^
 
 error: derive(Diagnostic): no nested attribute expected here
-  --> $DIR/subdiagnostic-derive.rs:144:27
+  --> $DIR/subdiagnostic-derive.rs:135:27
    |
 LL | #[label(no_crate_example, applicability = "machine-applicable")]
    |                           ^^^^^^^^^^^^^
 
 error: derive(Diagnostic): unsupported type attribute for subdiagnostic enum
-  --> $DIR/subdiagnostic-derive.rs:153:1
+  --> $DIR/subdiagnostic-derive.rs:144:1
    |
 LL | #[foo]
    | ^
 
 error: derive(Diagnostic): `#[bar]` is not a valid attribute
-  --> $DIR/subdiagnostic-derive.rs:167:5
+  --> $DIR/subdiagnostic-derive.rs:158:5
    |
 LL |     #[bar]
    |     ^
 
 error: derive(Diagnostic): `#[bar = ...]` is not a valid attribute
-  --> $DIR/subdiagnostic-derive.rs:179:5
+  --> $DIR/subdiagnostic-derive.rs:170:5
    |
 LL |     #[bar = "..."]
    |     ^
 
 error: derive(Diagnostic): `#[bar = ...]` is not a valid attribute
-  --> $DIR/subdiagnostic-derive.rs:191:5
+  --> $DIR/subdiagnostic-derive.rs:182:5
    |
 LL |     #[bar = 4]
    |     ^
 
 error: derive(Diagnostic): `#[bar(...)]` is not a valid attribute
-  --> $DIR/subdiagnostic-derive.rs:203:5
+  --> $DIR/subdiagnostic-derive.rs:194:5
    |
 LL |     #[bar("...")]
    |     ^
 
 error: derive(Diagnostic): no nested attribute expected here
-  --> $DIR/subdiagnostic-derive.rs:215:13
+  --> $DIR/subdiagnostic-derive.rs:206:13
    |
 LL |     #[label(code = "...")]
    |             ^^^^
 
 error: derive(Diagnostic): diagnostic slug must be first argument of a `#[label(...)]` attribute
-  --> $DIR/subdiagnostic-derive.rs:215:5
+  --> $DIR/subdiagnostic-derive.rs:206:5
    |
 LL |     #[label(code = "...")]
    |     ^
 
 error: derive(Diagnostic): the `#[primary_span]` attribute can only be applied to fields of type `Span` or `MultiSpan`
-  --> $DIR/subdiagnostic-derive.rs:244:5
+  --> $DIR/subdiagnostic-derive.rs:235:5
    |
 LL |     #[primary_span]
    |     ^
 
 error: derive(Diagnostic): label without `#[primary_span]` field
-  --> $DIR/subdiagnostic-derive.rs:241:1
+  --> $DIR/subdiagnostic-derive.rs:232:1
    |
 LL | #[label(no_crate_example)]
    | ^
 
 error: derive(Diagnostic): `#[applicability]` is only valid on suggestions
-  --> $DIR/subdiagnostic-derive.rs:254:5
+  --> $DIR/subdiagnostic-derive.rs:245:5
    |
 LL |     #[applicability]
    |     ^
 
 error: derive(Diagnostic): `#[bar]` is not a valid attribute
-  --> $DIR/subdiagnostic-derive.rs:264:5
+  --> $DIR/subdiagnostic-derive.rs:255:5
    |
 LL |     #[bar]
    |     ^
@@ -151,13 +145,13 @@ LL |     #[bar]
    = help: only `primary_span`, `applicability` and `skip_arg` are valid field attributes
 
 error: derive(Diagnostic): `#[bar = ...]` is not a valid attribute
-  --> $DIR/subdiagnostic-derive.rs:275:5
+  --> $DIR/subdiagnostic-derive.rs:266:5
    |
 LL |     #[bar = "..."]
    |     ^
 
 error: derive(Diagnostic): `#[bar(...)]` is not a valid attribute
-  --> $DIR/subdiagnostic-derive.rs:286:5
+  --> $DIR/subdiagnostic-derive.rs:277:5
    |
 LL |     #[bar("...")]
    |     ^
@@ -165,7 +159,7 @@ LL |     #[bar("...")]
    = help: only `primary_span`, `applicability` and `skip_arg` are valid field attributes
 
 error: unexpected unsupported untagged union
-  --> $DIR/subdiagnostic-derive.rs:302:1
+  --> $DIR/subdiagnostic-derive.rs:293:1
    |
 LL | / union AC {
 LL | |
@@ -175,97 +169,97 @@ LL | | }
    | |_^
 
 error: derive(Diagnostic): a diagnostic slug must be the first argument to the attribute
-  --> $DIR/subdiagnostic-derive.rs:317:27
+  --> $DIR/subdiagnostic-derive.rs:308:27
    |
 LL | #[label(no_crate_example, no_crate::example)]
    |                           ^^^^^^^^
 
 error: derive(Diagnostic): attribute specified multiple times
-  --> $DIR/subdiagnostic-derive.rs:330:5
+  --> $DIR/subdiagnostic-derive.rs:321:5
    |
 LL |     #[primary_span]
    |     ^
    |
 note: previously specified here
-  --> $DIR/subdiagnostic-derive.rs:327:5
+  --> $DIR/subdiagnostic-derive.rs:318:5
    |
 LL |     #[primary_span]
    |     ^
 
 error: derive(Diagnostic): subdiagnostic kind not specified
-  --> $DIR/subdiagnostic-derive.rs:336:8
+  --> $DIR/subdiagnostic-derive.rs:327:8
    |
 LL | struct AG {
    |        ^^
 
 error: derive(Diagnostic): attribute specified multiple times
-  --> $DIR/subdiagnostic-derive.rs:373:46
+  --> $DIR/subdiagnostic-derive.rs:364:46
    |
 LL | #[suggestion(no_crate_example, code = "...", code = "...")]
    |                                              ^^^^
    |
 note: previously specified here
-  --> $DIR/subdiagnostic-derive.rs:373:32
+  --> $DIR/subdiagnostic-derive.rs:364:32
    |
 LL | #[suggestion(no_crate_example, code = "...", code = "...")]
    |                                ^^^^
 
 error: derive(Diagnostic): attribute specified multiple times
-  --> $DIR/subdiagnostic-derive.rs:391:5
+  --> $DIR/subdiagnostic-derive.rs:382:5
    |
 LL |     #[applicability]
    |     ^
    |
 note: previously specified here
-  --> $DIR/subdiagnostic-derive.rs:388:5
+  --> $DIR/subdiagnostic-derive.rs:379:5
    |
 LL |     #[applicability]
    |     ^
 
 error: derive(Diagnostic): the `#[applicability]` attribute can only be applied to fields of type `Applicability`
-  --> $DIR/subdiagnostic-derive.rs:401:5
+  --> $DIR/subdiagnostic-derive.rs:392:5
    |
 LL |     #[applicability]
    |     ^
 
 error: derive(Diagnostic): suggestion without `code = "..."`
-  --> $DIR/subdiagnostic-derive.rs:414:1
+  --> $DIR/subdiagnostic-derive.rs:405:1
    |
 LL | #[suggestion(no_crate_example)]
    | ^
 
 error: derive(Diagnostic): invalid applicability
-  --> $DIR/subdiagnostic-derive.rs:424:62
+  --> $DIR/subdiagnostic-derive.rs:415:62
    |
 LL | #[suggestion(no_crate_example, code = "...", applicability = "foo")]
    |                                                              ^^^^^
 
 error: derive(Diagnostic): suggestion without `#[primary_span]` field
-  --> $DIR/subdiagnostic-derive.rs:442:1
+  --> $DIR/subdiagnostic-derive.rs:433:1
    |
 LL | #[suggestion(no_crate_example, code = "...")]
    | ^
 
 error: derive(Diagnostic): unsupported type attribute for subdiagnostic enum
-  --> $DIR/subdiagnostic-derive.rs:456:1
+  --> $DIR/subdiagnostic-derive.rs:447:1
    |
 LL | #[label]
    | ^
 
 error: derive(Diagnostic): `var` doesn't refer to a field on this type
-  --> $DIR/subdiagnostic-derive.rs:476:39
+  --> $DIR/subdiagnostic-derive.rs:467:39
    |
 LL | #[suggestion(no_crate_example, code = "{var}", applicability = "machine-applicable")]
    |                                       ^^^^^^^
 
 error: derive(Diagnostic): `var` doesn't refer to a field on this type
-  --> $DIR/subdiagnostic-derive.rs:495:43
+  --> $DIR/subdiagnostic-derive.rs:486:43
    |
 LL |     #[suggestion(no_crate_example, code = "{var}", applicability = "machine-applicable")]
    |                                           ^^^^^^^
 
 error: derive(Diagnostic): `#[suggestion_part]` is not a valid attribute
-  --> $DIR/subdiagnostic-derive.rs:518:5
+  --> $DIR/subdiagnostic-derive.rs:509:5
    |
 LL |     #[suggestion_part]
    |     ^
@@ -273,7 +267,7 @@ LL |     #[suggestion_part]
    = help: `#[suggestion_part(...)]` is only valid in multipart suggestions, use `#[primary_span]` instead
 
 error: derive(Diagnostic): `#[suggestion_part(...)]` is not a valid attribute
-  --> $DIR/subdiagnostic-derive.rs:521:5
+  --> $DIR/subdiagnostic-derive.rs:512:5
    |
 LL |     #[suggestion_part(code = "...")]
    |     ^
@@ -281,13 +275,13 @@ LL |     #[suggestion_part(code = "...")]
    = help: `#[suggestion_part(...)]` is only valid in multipart suggestions
 
 error: derive(Diagnostic): suggestion without `#[primary_span]` field
-  --> $DIR/subdiagnostic-derive.rs:515:1
+  --> $DIR/subdiagnostic-derive.rs:506:1
    |
 LL | #[suggestion(no_crate_example, code = "...")]
    | ^
 
 error: derive(Diagnostic): invalid nested attribute
-  --> $DIR/subdiagnostic-derive.rs:530:42
+  --> $DIR/subdiagnostic-derive.rs:521:42
    |
 LL | #[multipart_suggestion(no_crate_example, code = "...", applicability = "machine-applicable")]
    |                                          ^^^^
@@ -295,25 +289,25 @@ LL | #[multipart_suggestion(no_crate_example, code = "...", applicability = "mac
    = help: only `style` and `applicability` are valid nested attributes
 
 error: derive(Diagnostic): multipart suggestion without any `#[suggestion_part(...)]` fields
-  --> $DIR/subdiagnostic-derive.rs:530:1
+  --> $DIR/subdiagnostic-derive.rs:521:1
    |
 LL | #[multipart_suggestion(no_crate_example, code = "...", applicability = "machine-applicable")]
    | ^
 
 error: derive(Diagnostic): `#[suggestion_part(...)]` attribute without `code = "..."`
-  --> $DIR/subdiagnostic-derive.rs:540:5
+  --> $DIR/subdiagnostic-derive.rs:531:5
    |
 LL |     #[suggestion_part]
    |     ^
 
 error: derive(Diagnostic): `#[suggestion_part(...)]` attribute without `code = "..."`
-  --> $DIR/subdiagnostic-derive.rs:548:5
+  --> $DIR/subdiagnostic-derive.rs:539:5
    |
 LL |     #[suggestion_part()]
    |     ^
 
 error: derive(Diagnostic): `#[primary_span]` is not a valid attribute
-  --> $DIR/subdiagnostic-derive.rs:557:5
+  --> $DIR/subdiagnostic-derive.rs:548:5
    |
 LL |     #[primary_span]
    |     ^
@@ -321,127 +315,127 @@ LL |     #[primary_span]
    = help: multipart suggestions use one or more `#[suggestion_part]`s rather than one `#[primary_span]`
 
 error: derive(Diagnostic): multipart suggestion without any `#[suggestion_part(...)]` fields
-  --> $DIR/subdiagnostic-derive.rs:554:1
+  --> $DIR/subdiagnostic-derive.rs:545:1
    |
 LL | #[multipart_suggestion(no_crate_example)]
    | ^
 
 error: derive(Diagnostic): `#[suggestion_part(...)]` attribute without `code = "..."`
-  --> $DIR/subdiagnostic-derive.rs:565:5
+  --> $DIR/subdiagnostic-derive.rs:556:5
    |
 LL |     #[suggestion_part]
    |     ^
 
 error: derive(Diagnostic): `#[suggestion_part(...)]` attribute without `code = "..."`
-  --> $DIR/subdiagnostic-derive.rs:568:5
+  --> $DIR/subdiagnostic-derive.rs:559:5
    |
 LL |     #[suggestion_part()]
    |     ^
 
 error: derive(Diagnostic): `code` is the only valid nested attribute
-  --> $DIR/subdiagnostic-derive.rs:571:23
+  --> $DIR/subdiagnostic-derive.rs:562:23
    |
 LL |     #[suggestion_part(foo = "bar")]
    |                       ^^^
 
 error: derive(Diagnostic): the `#[suggestion_part(...)]` attribute can only be applied to fields of type `Span` or `MultiSpan`
-  --> $DIR/subdiagnostic-derive.rs:575:5
+  --> $DIR/subdiagnostic-derive.rs:566:5
    |
 LL |     #[suggestion_part(code = "...")]
    |     ^
 
 error: derive(Diagnostic): the `#[suggestion_part(...)]` attribute can only be applied to fields of type `Span` or `MultiSpan`
-  --> $DIR/subdiagnostic-derive.rs:578:5
+  --> $DIR/subdiagnostic-derive.rs:569:5
    |
 LL |     #[suggestion_part()]
    |     ^
 
 error: expected `,`
-  --> $DIR/subdiagnostic-derive.rs:571:27
+  --> $DIR/subdiagnostic-derive.rs:562:27
    |
 LL |     #[suggestion_part(foo = "bar")]
    |                           ^
 
 error: derive(Diagnostic): attribute specified multiple times
-  --> $DIR/subdiagnostic-derive.rs:586:37
+  --> $DIR/subdiagnostic-derive.rs:577:37
    |
 LL |     #[suggestion_part(code = "...", code = ",,,")]
    |                                     ^^^^
    |
 note: previously specified here
-  --> $DIR/subdiagnostic-derive.rs:586:23
+  --> $DIR/subdiagnostic-derive.rs:577:23
    |
 LL |     #[suggestion_part(code = "...", code = ",,,")]
    |                       ^^^^
 
 error: derive(Diagnostic): `#[applicability]` has no effect if all `#[suggestion]`/`#[multipart_suggestion]` attributes have a static `applicability = "..."`
-  --> $DIR/subdiagnostic-derive.rs:615:5
+  --> $DIR/subdiagnostic-derive.rs:606:5
    |
 LL |     #[applicability]
    |     ^
 
 error: derive(Diagnostic): expected exactly one string literal for `code = ...`
-  --> $DIR/subdiagnostic-derive.rs:663:28
+  --> $DIR/subdiagnostic-derive.rs:654:28
    |
 LL |     #[suggestion_part(code("foo"))]
    |                            ^^^^^
 
 error: unexpected token, expected `)`
-  --> $DIR/subdiagnostic-derive.rs:663:28
+  --> $DIR/subdiagnostic-derive.rs:654:28
    |
 LL |     #[suggestion_part(code("foo"))]
    |                            ^^^^^
 
 error: derive(Diagnostic): expected exactly one string literal for `code = ...`
-  --> $DIR/subdiagnostic-derive.rs:673:28
+  --> $DIR/subdiagnostic-derive.rs:664:28
    |
 LL |     #[suggestion_part(code("foo", "bar"))]
    |                            ^^^^^
 
 error: unexpected token, expected `)`
-  --> $DIR/subdiagnostic-derive.rs:673:28
+  --> $DIR/subdiagnostic-derive.rs:664:28
    |
 LL |     #[suggestion_part(code("foo", "bar"))]
    |                            ^^^^^
 
 error: derive(Diagnostic): expected exactly one string literal for `code = ...`
-  --> $DIR/subdiagnostic-derive.rs:683:28
+  --> $DIR/subdiagnostic-derive.rs:674:28
    |
 LL |     #[suggestion_part(code(3))]
    |                            ^
 
 error: unexpected token, expected `)`
-  --> $DIR/subdiagnostic-derive.rs:683:28
+  --> $DIR/subdiagnostic-derive.rs:674:28
    |
 LL |     #[suggestion_part(code(3))]
    |                            ^
 
 error: derive(Diagnostic): expected exactly one string literal for `code = ...`
-  --> $DIR/subdiagnostic-derive.rs:693:28
+  --> $DIR/subdiagnostic-derive.rs:684:28
    |
 LL |     #[suggestion_part(code())]
    |                            ^
 
 error: expected string literal
-  --> $DIR/subdiagnostic-derive.rs:702:30
+  --> $DIR/subdiagnostic-derive.rs:693:30
    |
 LL |     #[suggestion_part(code = 3)]
    |                              ^
 
 error: derive(Diagnostic): attribute specified multiple times
-  --> $DIR/subdiagnostic-derive.rs:744:1
+  --> $DIR/subdiagnostic-derive.rs:735:1
    |
 LL | #[suggestion(no_crate_example, code = "", style = "hidden", style = "normal")]
    | ^
    |
 note: previously specified here
-  --> $DIR/subdiagnostic-derive.rs:744:1
+  --> $DIR/subdiagnostic-derive.rs:735:1
    |
 LL | #[suggestion(no_crate_example, code = "", style = "hidden", style = "normal")]
    | ^
 
 error: derive(Diagnostic): `#[suggestion_hidden(...)]` is not a valid attribute
-  --> $DIR/subdiagnostic-derive.rs:753:1
+  --> $DIR/subdiagnostic-derive.rs:744:1
    |
 LL | #[suggestion_hidden(no_crate_example, code = "")]
    | ^
@@ -449,7 +443,7 @@ LL | #[suggestion_hidden(no_crate_example, code = "")]
    = help: Use `#[suggestion(..., style = "hidden")]` instead
 
 error: derive(Diagnostic): `#[suggestion_hidden(...)]` is not a valid attribute
-  --> $DIR/subdiagnostic-derive.rs:761:1
+  --> $DIR/subdiagnostic-derive.rs:752:1
    |
 LL | #[suggestion_hidden(no_crate_example, code = "", style = "normal")]
    | ^
@@ -457,7 +451,7 @@ LL | #[suggestion_hidden(no_crate_example, code = "", style = "normal")]
    = help: Use `#[suggestion(..., style = "hidden")]` instead
 
 error: derive(Diagnostic): invalid suggestion style
-  --> $DIR/subdiagnostic-derive.rs:769:51
+  --> $DIR/subdiagnostic-derive.rs:760:51
    |
 LL | #[suggestion(no_crate_example, code = "", style = "foo")]
    |                                                   ^^^^^
@@ -465,25 +459,25 @@ LL | #[suggestion(no_crate_example, code = "", style = "foo")]
    = help: valid styles are `normal`, `short`, `hidden`, `verbose` and `tool-only`
 
 error: expected string literal
-  --> $DIR/subdiagnostic-derive.rs:777:51
+  --> $DIR/subdiagnostic-derive.rs:768:51
    |
 LL | #[suggestion(no_crate_example, code = "", style = 42)]
    |                                                   ^^
 
 error: derive(Diagnostic): a diagnostic slug must be the first argument to the attribute
-  --> $DIR/subdiagnostic-derive.rs:785:43
+  --> $DIR/subdiagnostic-derive.rs:776:43
    |
 LL | #[suggestion(no_crate_example, code = "", style)]
    |                                           ^^^^^
 
 error: expected `=`
-  --> $DIR/subdiagnostic-derive.rs:793:48
+  --> $DIR/subdiagnostic-derive.rs:784:48
    |
 LL | #[suggestion(no_crate_example, code = "", style("foo"))]
    |                                                ^
 
 error: derive(Diagnostic): `#[primary_span]` is not a valid attribute
-  --> $DIR/subdiagnostic-derive.rs:804:5
+  --> $DIR/subdiagnostic-derive.rs:795:5
    |
 LL |     #[primary_span]
    |     ^
@@ -492,7 +486,7 @@ LL |     #[primary_span]
    = help: to create a suggestion with multiple spans, use `#[multipart_suggestion]` instead
 
 error: derive(Diagnostic): suggestion without `#[primary_span]` field
-  --> $DIR/subdiagnostic-derive.rs:801:1
+  --> $DIR/subdiagnostic-derive.rs:792:1
    |
 LL | #[suggestion(no_crate_example, code = "")]
    | ^
@@ -504,52 +498,52 @@ LL | #[foo]
    |   ^^^
 
 error: cannot find attribute `foo` in this scope
-  --> $DIR/subdiagnostic-derive.rs:153:3
+  --> $DIR/subdiagnostic-derive.rs:144:3
    |
 LL | #[foo]
    |   ^^^
 
 error: cannot find attribute `bar` in this scope
-  --> $DIR/subdiagnostic-derive.rs:167:7
+  --> $DIR/subdiagnostic-derive.rs:158:7
    |
 LL |     #[bar]
    |       ^^^
 
 error: cannot find attribute `bar` in this scope
-  --> $DIR/subdiagnostic-derive.rs:179:7
+  --> $DIR/subdiagnostic-derive.rs:170:7
    |
 LL |     #[bar = "..."]
    |       ^^^
 
 error: cannot find attribute `bar` in this scope
-  --> $DIR/subdiagnostic-derive.rs:191:7
+  --> $DIR/subdiagnostic-derive.rs:182:7
    |
 LL |     #[bar = 4]
    |       ^^^
 
 error: cannot find attribute `bar` in this scope
-  --> $DIR/subdiagnostic-derive.rs:203:7
+  --> $DIR/subdiagnostic-derive.rs:194:7
    |
 LL |     #[bar("...")]
    |       ^^^
 
 error: cannot find attribute `bar` in this scope
-  --> $DIR/subdiagnostic-derive.rs:264:7
+  --> $DIR/subdiagnostic-derive.rs:255:7
    |
 LL |     #[bar]
    |       ^^^
 
 error: cannot find attribute `bar` in this scope
-  --> $DIR/subdiagnostic-derive.rs:275:7
+  --> $DIR/subdiagnostic-derive.rs:266:7
    |
 LL |     #[bar = "..."]
    |       ^^^
 
 error: cannot find attribute `bar` in this scope
-  --> $DIR/subdiagnostic-derive.rs:286:7
+  --> $DIR/subdiagnostic-derive.rs:277:7
    |
 LL |     #[bar("...")]
    |       ^^^
 
-error: aborting due to 83 previous errors
+error: aborting due to 82 previous errors