Auto merge of #143779 - JonathanBrouwer:automatically_derived_parser, r=<try>

bors · bors · commit bc146279bdc1 · 2025-07-12T18:51:56.000Z
Port `#[automatically_derived]` to the new attribute parsing infrastructure Ports `#[automatically_derived]` to the new attribute parsing infrastructure for #131229 (comment) r? `@oli-obk` cc `@jdonszelmann`
diff --git a/compiler/rustc_ast/src/attr/mod.rs b/compiler/rustc_ast/src/attr/mod.rs
@@ -217,6 +217,10 @@ impl AttributeExt for Attribute {
             _ => None,
         }
     }
+
+    fn is_automatically_derived_attr(&self) -> bool {
+        self.has_name(sym::automatically_derived)
+    }
 }
 
 impl Attribute {
@@ -810,6 +814,7 @@ pub trait AttributeExt: Debug {
             .iter()
             .any(|kind| self.has_name(*kind))
     }
+    fn is_automatically_derived_attr(&self) -> bool;
 
     /// Returns the documentation and its kind if this is a doc comment or a sugared doc comment.
     /// * `///doc` returns `Some(("doc", CommentKind::Line))`.
diff --git a/compiler/rustc_attr_data_structures/src/attributes.rs b/compiler/rustc_attr_data_structures/src/attributes.rs
@@ -207,6 +207,9 @@ pub enum AttributeKind {
     /// Represents `#[rustc_as_ptr]` (used by the `dangling_pointers_from_temporaries` lint).
     AsPtr(Span),
 
+    /// Represents `#[automatically_derived]`
+    AutomaticallyDerived(Span),
+
     /// Represents `#[rustc_default_body_unstable]`.
     BodyStability {
         stability: DefaultBodyStability,
diff --git a/compiler/rustc_attr_data_structures/src/encode_cross_crate.rs b/compiler/rustc_attr_data_structures/src/encode_cross_crate.rs
@@ -18,6 +18,7 @@ impl AttributeKind {
             AllowIncoherentImpl(..) => No,
             AllowInternalUnstable(..) => Yes,
             AsPtr(..) => Yes,
+            AutomaticallyDerived(..) => Yes,
             BodyStability { .. } => No,
             CoherenceIsCore => No,
             Coinductive(..) => No,
diff --git a/compiler/rustc_attr_parsing/src/attributes/lint_helpers.rs b/compiler/rustc_attr_parsing/src/attributes/lint_helpers.rs
@@ -24,3 +24,10 @@ impl<S: Stage> NoArgsAttributeParser<S> for PassByValueParser {
     const ON_DUPLICATE: OnDuplicate<S> = OnDuplicate::Error;
     const CREATE: fn(Span) -> AttributeKind = AttributeKind::PassByValue;
 }
+
+pub(crate) struct AutomaticallyDerivedParser;
+impl<S: Stage> NoArgsAttributeParser<S> for AutomaticallyDerivedParser {
+    const PATH: &[Symbol] = &[sym::automatically_derived];
+    const ON_DUPLICATE: OnDuplicate<S> = OnDuplicate::Warn;
+    const CREATE: fn(Span) -> AttributeKind = AttributeKind::AutomaticallyDerived;
+}
diff --git a/compiler/rustc_attr_parsing/src/context.rs b/compiler/rustc_attr_parsing/src/context.rs
@@ -27,7 +27,9 @@ use crate::attributes::link_attrs::{
     ExportStableParser, FfiConstParser, FfiPureParser, LinkNameParser, LinkSectionParser,
     StdInternalSymbolParser,
 };
-use crate::attributes::lint_helpers::{AsPtrParser, PassByValueParser, PubTransparentParser};
+use crate::attributes::lint_helpers::{
+    AsPtrParser, AutomaticallyDerivedParser, PassByValueParser, PubTransparentParser,
+};
 use crate::attributes::loop_match::{ConstContinueParser, LoopMatchParser};
 use crate::attributes::must_use::MustUseParser;
 use crate::attributes::no_implicit_prelude::NoImplicitPreludeParser;
@@ -153,6 +155,7 @@ attribute_parsers!(
         Single<TransparencyParser>,
         Single<WithoutArgs<AllowIncoherentImplParser>>,
         Single<WithoutArgs<AsPtrParser>>,
+        Single<WithoutArgs<AutomaticallyDerivedParser>>,
         Single<WithoutArgs<CoherenceIsCoreParser>>,
         Single<WithoutArgs<CoinductiveParser>>,
         Single<WithoutArgs<ColdParser>>,
diff --git a/compiler/rustc_hir/src/hir.rs b/compiler/rustc_hir/src/hir.rs
@@ -1304,6 +1304,7 @@ impl AttributeExt for Attribute {
             Attribute::Parsed(AttributeKind::DocComment { span, .. }) => *span,
             Attribute::Parsed(AttributeKind::MayDangle(span)) => *span,
             Attribute::Parsed(AttributeKind::Ignore { span, .. }) => *span,
+            Attribute::Parsed(AttributeKind::AutomaticallyDerived(span)) => *span,
             a => panic!("can't get the span of an arbitrary parsed attribute: {a:?}"),
         }
     }
@@ -1334,6 +1335,11 @@ impl AttributeExt for Attribute {
             _ => None,
         }
     }
+
+    fn is_automatically_derived_attr(&self) -> bool {
+        matches!(self, Attribute::Parsed(AttributeKind::AutomaticallyDerived(..)))
+    }
+
     #[inline]
     fn doc_str_and_comment_kind(&self) -> Option<(Symbol, CommentKind)> {
         match &self {
diff --git a/compiler/rustc_lint/src/default_could_be_derived.rs b/compiler/rustc_lint/src/default_could_be_derived.rs
@@ -1,3 +1,4 @@
+use rustc_attr_data_structures::{AttributeKind, find_attr};
 use rustc_data_structures::fx::FxHashMap;
 use rustc_errors::{Applicability, Diag};
 use rustc_hir as hir;
@@ -62,7 +63,7 @@ impl<'tcx> LateLintPass<'tcx> for DefaultCouldBeDerived {
         let hir::ImplItemKind::Fn(_sig, body_id) = impl_item.kind else { return };
         let assoc = cx.tcx.associated_item(impl_item.owner_id);
         let parent = assoc.container_id(cx.tcx);
-        if cx.tcx.has_attr(parent, sym::automatically_derived) {
+        if find_attr!(cx.tcx.get_all_attrs(parent), AttributeKind::AutomaticallyDerived(..)) {
             // We don't care about what `#[derive(Default)]` produces in this lint.
             return;
         }
diff --git a/compiler/rustc_lint/src/levels.rs b/compiler/rustc_lint/src/levels.rs
@@ -644,7 +644,7 @@ impl<'s, P: LintLevelsProvider> LintLevelsBuilder<'s, P> {
     ) {
         let sess = self.sess;
         for (attr_index, attr) in attrs.iter().enumerate() {
-            if attr.has_name(sym::automatically_derived) {
+            if attr.is_automatically_derived_attr() {
                 self.insert(
                     LintId::of(SINGLE_USE_LIFETIMES),
                     LevelAndSource {
diff --git a/compiler/rustc_middle/src/ty/mod.rs b/compiler/rustc_middle/src/ty/mod.rs
@@ -28,7 +28,7 @@ use rustc_abi::{Align, FieldIdx, Integer, IntegerType, ReprFlags, ReprOptions, V
 use rustc_ast::expand::StrippedCfgItem;
 use rustc_ast::node_id::NodeMap;
 pub use rustc_ast_ir::{Movability, Mutability, try_visit};
-use rustc_attr_data_structures::AttributeKind;
+use rustc_attr_data_structures::{AttributeKind, find_attr};
 use rustc_data_structures::fx::{FxHashMap, FxHashSet, FxIndexMap, FxIndexSet};
 use rustc_data_structures::intern::Interned;
 use rustc_data_structures::stable_hasher::{HashStable, StableHasher};
@@ -2031,7 +2031,7 @@ impl<'tcx> TyCtxt<'tcx> {
 
     /// Check if the given `DefId` is `#\[automatically_derived\]`.
     pub fn is_automatically_derived(self, def_id: DefId) -> bool {
-        self.has_attr(def_id, sym::automatically_derived)
+        find_attr!(self.get_all_attrs(def_id), AttributeKind::AutomaticallyDerived(..))
     }
 
     /// Looks up the span of `impl_did` if the impl is local; otherwise returns `Err`
diff --git a/compiler/rustc_mir_build/src/thir/pattern/const_to_pat.rs b/compiler/rustc_mir_build/src/thir/pattern/const_to_pat.rs
@@ -2,6 +2,7 @@ use core::ops::ControlFlow;
 
 use rustc_abi::{FieldIdx, VariantIdx};
 use rustc_apfloat::Float;
+use rustc_attr_data_structures::{AttributeKind, find_attr};
 use rustc_data_structures::fx::FxHashSet;
 use rustc_errors::Diag;
 use rustc_hir as hir;
@@ -15,7 +16,7 @@ use rustc_middle::ty::{
 };
 use rustc_middle::{mir, span_bug};
 use rustc_span::def_id::DefId;
-use rustc_span::{DUMMY_SP, Span, sym};
+use rustc_span::{DUMMY_SP, Span};
 use rustc_trait_selection::traits::ObligationCause;
 use rustc_trait_selection::traits::query::evaluate_obligation::InferCtxtExt;
 use tracing::{debug, instrument, trace};
@@ -495,7 +496,8 @@ fn type_has_partial_eq_impl<'tcx>(
     let mut structural_peq = false;
     let mut impl_def_id = None;
     for def_id in tcx.non_blanket_impls_for_ty(partial_eq_trait_id, ty) {
-        automatically_derived = tcx.has_attr(def_id, sym::automatically_derived);
+        automatically_derived =
+            find_attr!(tcx.get_all_attrs(def_id), AttributeKind::AutomaticallyDerived(..));
         impl_def_id = Some(def_id);
     }
     for _ in tcx.non_blanket_impls_for_ty(structural_partial_eq_trait_id, ty) {
diff --git a/compiler/rustc_parse/src/validate_attr.rs b/compiler/rustc_parse/src/validate_attr.rs
@@ -316,6 +316,7 @@ pub fn check_builtin_meta_item(
                 | sym::rustc_layout_scalar_valid_range_start
                 | sym::rustc_layout_scalar_valid_range_end
                 | sym::no_implicit_prelude
+                | sym::automatically_derived
         ) {
             return;
         }
diff --git a/compiler/rustc_passes/src/check_attr.rs b/compiler/rustc_passes/src/check_attr.rs
@@ -152,6 +152,14 @@ impl<'tcx> CheckAttrVisitor<'tcx> {
                 Attribute::Parsed(AttributeKind::Confusables { first_span, .. }) => {
                     self.check_confusables(*first_span, target);
                 }
+                Attribute::Parsed(AttributeKind::AutomaticallyDerived(attr_span)) => self
+                    .check_generic_attr(
+                        hir_id,
+                        sym::automatically_derived,
+                        *attr_span,
+                        target,
+                        Target::Impl,
+                    ),
                 Attribute::Parsed(
                     AttributeKind::Stability { span, .. }
                     | AttributeKind::ConstStability { span, .. },
@@ -335,9 +343,6 @@ impl<'tcx> CheckAttrVisitor<'tcx> {
                         [sym::should_panic, ..] => {
                             self.check_generic_attr_unparsed(hir_id, attr, target, Target::Fn)
                         }
-                        [sym::automatically_derived, ..] => {
-                            self.check_generic_attr_unparsed(hir_id, attr, target, Target::Impl)
-                        }
                         [sym::proc_macro, ..] => {
                             self.check_proc_macro(hir_id, target, ProcMacroKind::FunctionLike)
                         }
@@ -2814,7 +2819,6 @@ fn check_invalid_crate_level_attr(tcx: TyCtxt<'_>, attrs: &[Attribute]) {
     // resolution for the attribute macro error.
     const ATTRS_TO_CHECK: &[Symbol] = &[
         sym::macro_export,
-        sym::automatically_derived,
         sym::rustc_main,
         sym::derive,
         sym::test,
@@ -2837,6 +2841,8 @@ fn check_invalid_crate_level_attr(tcx: TyCtxt<'_>, attrs: &[Attribute]) {
             (*first_attr_span, sym::repr)
         } else if let Attribute::Parsed(AttributeKind::Path(.., span)) = attr {
             (*span, sym::path)
+        } else if let Attribute::Parsed(AttributeKind::AutomaticallyDerived(span)) = attr {
+            (*span, sym::automatically_derived)
         } else {
             continue;
         };
diff --git a/compiler/rustc_passes/src/liveness.rs b/compiler/rustc_passes/src/liveness.rs
@@ -97,7 +97,7 @@ use rustc_middle::query::Providers;
 use rustc_middle::span_bug;
 use rustc_middle::ty::{self, RootVariableMinCaptureList, Ty, TyCtxt};
 use rustc_session::lint;
-use rustc_span::{BytePos, Span, Symbol, sym};
+use rustc_span::{BytePos, Span, Symbol};
 use tracing::{debug, instrument};
 
 use self::LiveNodeKind::*;
@@ -140,7 +140,7 @@ fn check_liveness(tcx: TyCtxt<'_>, def_id: LocalDefId) {
     // Don't run unused pass for #[derive()]
     let parent = tcx.local_parent(def_id);
     if let DefKind::Impl { .. } = tcx.def_kind(parent)
-        && tcx.has_attr(parent, sym::automatically_derived)
+        && find_attr!(tcx.get_all_attrs(parent), AttributeKind::AutomaticallyDerived(..))
     {
         return;
     }
diff --git a/src/librustdoc/clean/types.rs b/src/librustdoc/clean/types.rs
@@ -796,6 +796,9 @@ impl Item {
                             }
                             Some(format!("#[target_feature({output})]"))
                         }
+                        hir::Attribute::Parsed(AttributeKind::AutomaticallyDerived(..)) => {
+                            Some("#[automatically_derived]".to_string())
+                        }
                         _ => Some({
                             let mut s = rustc_hir_pretty::attribute_to_string(&tcx, attr);
                             assert_eq!(s.pop(), Some('\n'));
diff --git a/src/tools/clippy/clippy_lints/src/format_args.rs b/src/tools/clippy/clippy_lints/src/format_args.rs
@@ -30,6 +30,7 @@ use rustc_span::edition::Edition::Edition2021;
 use rustc_span::{Span, Symbol, sym};
 use rustc_trait_selection::infer::TyCtxtInferExt;
 use rustc_trait_selection::traits::{Obligation, ObligationCause, Selection, SelectionContext};
+use rustc_attr_data_structures::{AttributeKind, find_attr};
 
 declare_clippy_lint! {
     /// ### What it does
@@ -656,7 +657,7 @@ impl<'tcx> FormatArgsExpr<'_, 'tcx> {
                     };
                     let selection = SelectionContext::new(&infcx).select(&obligation);
                     let derived = if let Ok(Some(Selection::UserDefined(data))) = selection {
-                        tcx.has_attr(data.impl_def_id, sym::automatically_derived)
+                        find_attr!(tcx.get_all_attrs(data.impl_def_id), AttributeKind::AutomaticallyDerived(..))
                     } else {
                         false
                     };
diff --git a/src/tools/clippy/clippy_lints_internal/src/derive_deserialize_allowing_unknown.rs b/src/tools/clippy/clippy_lints_internal/src/derive_deserialize_allowing_unknown.rs
@@ -88,7 +88,7 @@ impl<'tcx> LateLintPass<'tcx> for DeriveDeserializeAllowingUnknown {
         }
 
         // Is it derived?
-        if !cx.tcx.has_attr(item.owner_id, sym::automatically_derived) {
+        if !find_attr!(cx.tcx.get_all_attrs(item.owner_id), AttributeKind::AutomaticallyDerived(..)) {
             return;
         }
 
diff --git a/src/tools/clippy/clippy_utils/src/lib.rs b/src/tools/clippy/clippy_utils/src/lib.rs
@@ -1784,9 +1784,9 @@ pub fn in_automatically_derived(tcx: TyCtxt<'_>, id: HirId) -> bool {
     tcx.hir_parent_owner_iter(id)
         .filter(|(_, node)| matches!(node, OwnerNode::Item(item) if matches!(item.kind, ItemKind::Impl(_))))
         .any(|(id, _)| {
-            has_attr(
+            find_attr!(
                 tcx.hir_attrs(tcx.local_def_id_to_hir_id(id.def_id)),
-                sym::automatically_derived,
+                AttributeKind::AutomaticallyDerived(..)
             )
         })
 }
diff --git a/tests/ui/attributes/malformed-attrs.stderr b/tests/ui/attributes/malformed-attrs.stderr
@@ -164,12 +164,6 @@ error: malformed `debugger_visualizer` attribute input
 LL | #[debugger_visualizer]
    | ^^^^^^^^^^^^^^^^^^^^^^ help: must be of the form: `#[debugger_visualizer(natvis_file = "...", gdb_script_file = "...")]`
 
-error: malformed `automatically_derived` attribute input
-  --> $DIR/malformed-attrs.rs:191:1
-   |
-LL | #[automatically_derived = 18]
-   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: must be of the form: `#[automatically_derived]`
-
 error: malformed `thread_local` attribute input
   --> $DIR/malformed-attrs.rs:203:1
    |
@@ -546,6 +540,15 @@ LL |     #[unsafe(ffi_const = 1)]
    |     |                  didn't expect any arguments here
    |     help: must be of the form: `#[ffi_const]`
 
+error[E0565]: malformed `automatically_derived` attribute input
+  --> $DIR/malformed-attrs.rs:191:1
+   |
+LL | #[automatically_derived = 18]
+   | ^^^^^^^^^^^^^^^^^^^^^^^^----^
+   | |                       |
+   | |                       didn't expect any arguments here
+   | help: must be of the form: `#[automatically_derived]`
+
 error[E0565]: malformed `non_exhaustive` attribute input
   --> $DIR/malformed-attrs.rs:197:1
    |
diff --git a/tests/ui/feature-gates/issue-43106-gating-of-builtin-attrs-error.stderr b/tests/ui/feature-gates/issue-43106-gating-of-builtin-attrs-error.stderr
@@ -121,21 +121,6 @@ LL - #![rustc_main]
 LL + #[rustc_main]
    |
 
-error: `automatically_derived` attribute cannot be used at crate level
-  --> $DIR/issue-43106-gating-of-builtin-attrs-error.rs:23:1
-   |
-LL | #![automatically_derived]
-   | ^^^^^^^^^^^^^^^^^^^^^^^^^
-...
-LL | mod inline {
-   |     ------ the inner attribute doesn't annotate this module
-   |
-help: perhaps you meant to use an outer attribute
-   |
-LL - #![automatically_derived]
-LL + #[automatically_derived]
-   |
-
 error: `repr` attribute cannot be used at crate level
   --> $DIR/issue-43106-gating-of-builtin-attrs-error.rs:19:1
    |
@@ -166,6 +151,21 @@ LL - #![path = "3800"]
 LL + #[path = "3800"]
    |
 
+error: `automatically_derived` attribute cannot be used at crate level
+  --> $DIR/issue-43106-gating-of-builtin-attrs-error.rs:23:1
+   |
+LL | #![automatically_derived]
+   | ^^^^^^^^^^^^^^^^^^^^^^^^^
+...
+LL | mod inline {
+   |     ------ the inner attribute doesn't annotate this module
+   |
+help: perhaps you meant to use an outer attribute
+   |
+LL - #![automatically_derived]
+LL + #[automatically_derived]
+   |
+
 error[E0518]: attribute should be applied to function or closure
   --> $DIR/issue-43106-gating-of-builtin-attrs-error.rs:42:17
    |
diff --git a/tests/ui/lint/unused/unused-attr-duplicate.stderr b/tests/ui/lint/unused/unused-attr-duplicate.stderr
@@ -40,18 +40,6 @@ LL | #[should_panic]
    | ^^^^^^^^^^^^^^^
    = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in a future release!
 
-error: unused attribute
-  --> $DIR/unused-attr-duplicate.rs:70:1
-   |
-LL | #[automatically_derived]
-   | ^^^^^^^^^^^^^^^^^^^^^^^^ help: remove this attribute
-   |
-note: attribute also specified here
-  --> $DIR/unused-attr-duplicate.rs:69:1
-   |
-LL | #[automatically_derived]
-   | ^^^^^^^^^^^^^^^^^^^^^^^^
-
 error: unused attribute
   --> $DIR/unused-attr-duplicate.rs:14:1
    |
@@ -190,6 +178,18 @@ note: attribute also specified here
 LL | #[non_exhaustive]
    | ^^^^^^^^^^^^^^^^^
 
+error: unused attribute
+  --> $DIR/unused-attr-duplicate.rs:70:1
+   |
+LL | #[automatically_derived]
+   | ^^^^^^^^^^^^^^^^^^^^^^^^ help: remove this attribute
+   |
+note: attribute also specified here
+  --> $DIR/unused-attr-duplicate.rs:69:1
+   |
+LL | #[automatically_derived]
+   | ^^^^^^^^^^^^^^^^^^^^^^^^
+
 error: unused attribute
   --> $DIR/unused-attr-duplicate.rs:74:1
    |

Original file line number	Diff line number	Diff line change
`@@ -217,6 +217,10 @@ impl AttributeExt for Attribute {`
`217`	`217`	`_ => None,`
`218`	`218`	`}`
`219`	`219`	`}`
	`220`	`+`
	`221`	`+ fn is_automatically_derived_attr(&self) -> bool {`
	`222`	`+ self.has_name(sym::automatically_derived)`
	`223`	`+ }`
`220`	`224`	`}`
`221`	`225`
`222`	`226`	`impl Attribute {`
`@@ -810,6 +814,7 @@ pub trait AttributeExt: Debug {`
`810`	`814`	`.iter()`
`811`	`815`	`.any(\|kind\| self.has_name(*kind))`
`812`	`816`	`}`
	`817`	`+ fn is_automatically_derived_attr(&self) -> bool;`
`813`	`818`
`814`	`819`	`/// Returns the documentation and its kind if this is a doc comment or a sugared doc comment.`
`815`	`820`	/// * `///doc` returns `Some(("doc", CommentKind::Line))`.
Original file line number	Diff line number	Diff line change
`@@ -1304,6 +1304,7 @@ impl AttributeExt for Attribute {`
`1304`	`1304`	`Attribute::Parsed(AttributeKind::DocComment { span, .. }) => *span,`
`1305`	`1305`	`Attribute::Parsed(AttributeKind::MayDangle(span)) => *span,`
`1306`	`1306`	`Attribute::Parsed(AttributeKind::Ignore { span, .. }) => *span,`
	`1307`	`+ Attribute::Parsed(AttributeKind::AutomaticallyDerived(span)) => *span,`
`1307`	`1308`	`a => panic!("can't get the span of an arbitrary parsed attribute: {a:?}"),`
`1308`	`1309`	`}`
`1309`	`1310`	`}`
`@@ -1334,6 +1335,11 @@ impl AttributeExt for Attribute {`
`1334`	`1335`	`_ => None,`
`1335`	`1336`	`}`
`1336`	`1337`	`}`
	`1338`	`+`
	`1339`	`+ fn is_automatically_derived_attr(&self) -> bool {`
	`1340`	`+ matches!(self, Attribute::Parsed(AttributeKind::AutomaticallyDerived(..)))`
	`1341`	`+ }`
	`1342`	`+`
`1337`	`1343`	`#[inline]`
`1338`	`1344`	`fn doc_str_and_comment_kind(&self) -> Option<(Symbol, CommentKind)> {`
`1339`	`1345`	`match &self {`