Use the new attributes throughout the codebase

Signed-off-by: Jonathan Brouwer <[email protected]>
rust-lang · jhpratt · Jul 1, 2025 · Jul 25, 2025 · Jul 26, 2025 · Jul 7, 2025
commit ec637000c6d5436b165a9b9ab4b008c036d22c99
diff --git a/compiler/rustc_attr_parsing/src/attributes/proc_macro_attrs.rs b/compiler/rustc_attr_parsing/src/attributes/proc_macro_attrs.rs
@@ -61,17 +61,17 @@ fn parse_derive_like<S: Stage>(
     trait_name_mandatory: bool,
 ) -> Option<(Option<Symbol>, ThinVec<Symbol>)> {
     let Some(list) = args.list() else {
+        // For #[rustc_builtin_macro], it is permitted to leave out the trait name
+        if args.no_args().is_ok() && !trait_name_mandatory {
+            return Some((None, ThinVec::new()));
+        }
         cx.expected_list(cx.attr_span);
         return None;
     };
     let mut items = list.mixed();
 
     // Parse the name of the trait that is derived.
     let Some(trait_attr) = items.next() else {
-        // For #[rustc_builtin_macro], it is permitted to leave out the trait name
-        if !trait_name_mandatory {
-            return None;
-        }
         cx.expected_at_least_one_argument(list.span);
         return None;
     };

diff --git a/compiler/rustc_builtin_macros/src/proc_macro_harness.rs b/compiler/rustc_builtin_macros/src/proc_macro_harness.rs
@@ -1,11 +1,13 @@
-use std::mem;
+use std::{mem, slice};
 
 use rustc_ast::ptr::P;
 use rustc_ast::visit::{self, Visitor};
-use rustc_ast::{self as ast, NodeId, attr};
+use rustc_ast::{self as ast, HasNodeId, NodeId, attr};
 use rustc_ast_pretty::pprust;
+use rustc_attr_data_structures::AttributeKind;
+use rustc_attr_parsing::AttributeParser;
 use rustc_errors::DiagCtxtHandle;
-use rustc_expand::base::{ExtCtxt, ResolverExpand, parse_macro_name_and_helper_attrs};
+use rustc_expand::base::{ExtCtxt, ResolverExpand};
 use rustc_expand::expand::{AstFragment, ExpansionConfig};
 use rustc_feature::Features;
 use rustc_session::Session;
@@ -22,7 +24,7 @@ struct ProcMacroDerive {
     trait_name: Symbol,
     function_ident: Ident,
     span: Span,
-    attrs: Vec<Symbol>,
+    attrs: ThinVec<Symbol>,
 }
 
 struct ProcMacroDef {
@@ -41,6 +43,7 @@ struct CollectProcMacros<'a> {
     macros: Vec<ProcMacro>,
     in_root: bool,
     dcx: DiagCtxtHandle<'a>,
+    session: &'a Session,
     source_map: &'a SourceMap,
     is_proc_macro_crate: bool,
     is_test_crate: bool,
@@ -63,6 +66,7 @@ pub fn inject(
         macros: Vec::new(),
         in_root: true,
         dcx,
+        session: sess,
         source_map: sess.source_map(),
         is_proc_macro_crate,
         is_test_crate,
@@ -98,8 +102,18 @@ impl<'a> CollectProcMacros<'a> {
         function_ident: Ident,
         attr: &'a ast::Attribute,
     ) {
-        let Some((trait_name, proc_attrs)) =
-            parse_macro_name_and_helper_attrs(self.dcx, attr, "derive")
+        let Some(rustc_hir::Attribute::Parsed(AttributeKind::ProcMacroDerive {
+            trait_name,
+            helper_attrs,
+            ..
+        })) = AttributeParser::parse_limited(
+            self.session,
+            slice::from_ref(attr),
+            sym::proc_macro_derive,
+            item.span,
+            item.node_id(),
+            None,
+        )
         else {
             return;
         };
@@ -110,7 +124,7 @@ impl<'a> CollectProcMacros<'a> {
                 span: item.span,
                 trait_name,
                 function_ident,
-                attrs: proc_attrs,
+                attrs: helper_attrs,
             }));
         } else {
             let msg = if !self.in_root {

diff --git a/compiler/rustc_expand/src/base.rs b/compiler/rustc_expand/src/base.rs
@@ -861,7 +861,7 @@ impl SyntaxExtension {
     /// | (unspecified) | no  | if-ext        | if-ext   | yes |
     /// | external      | no  | if-ext        | if-ext   | yes |
     /// | yes           | yes | yes           | yes      | yes |
-    fn get_collapse_debuginfo(sess: &Session, attrs: &[impl AttributeExt], ext: bool) -> bool {
+    fn get_collapse_debuginfo(sess: &Session, attrs: &[hir::Attribute], ext: bool) -> bool {
         let flag = sess.opts.cg.collapse_macro_debuginfo;
         let attr = ast::attr::find_by_name(attrs, sym::collapse_debuginfo)
             .and_then(|attr| {
@@ -872,7 +872,7 @@ impl SyntaxExtension {
                     .ok()
             })
             .unwrap_or_else(|| {
-                if ast::attr::contains_name(attrs, sym::rustc_builtin_macro) {
+                if find_attr!(attrs, AttributeKind::RustcBuiltinMacro { .. }) {
                     CollapseMacroDebuginfo::Yes
                 } else {
                     CollapseMacroDebuginfo::Unspecified
@@ -915,16 +915,18 @@ impl SyntaxExtension {
         let collapse_debuginfo = Self::get_collapse_debuginfo(sess, attrs, !is_local);
         tracing::debug!(?name, ?local_inner_macros, ?collapse_debuginfo, ?allow_internal_unsafe);
 
-        let (builtin_name, helper_attrs) = ast::attr::find_by_name(attrs, sym::rustc_builtin_macro)
-            .map(|attr| {
-                // Override `helper_attrs` passed above if it's a built-in macro,
-                // marking `proc_macro_derive` macros as built-in is not a realistic use case.
-                parse_macro_name_and_helper_attrs(sess.dcx(), attr, "built-in").map_or_else(
-                    || (Some(name), Vec::new()),
-                    |(name, helper_attrs)| (Some(name), helper_attrs),
-                )
-            })
-            .unwrap_or_else(|| (None, helper_attrs));
+        let (builtin_name, helper_attrs) = match find_attr!(attrs, AttributeKind::RustcBuiltinMacro { builtin_name, helper_attrs, .. } => (builtin_name, helper_attrs))
+        {
+            // Override `helper_attrs` passed above if it's a built-in macro,
+            // marking `proc_macro_derive` macros as built-in is not a realistic use case.
+            Some((Some(name), helper_attrs)) => {
+                (Some(*name), helper_attrs.iter().copied().collect())
+            }
+            Some((None, _)) => (Some(name), Vec::new()),
+
+            // Not a built-in macro
+            None => (None, helper_attrs),
+        };
 
         let stability = find_attr!(attrs, AttributeKind::Stability { stability, .. } => *stability);
 

diff --git a/compiler/rustc_hir/src/hir.rs b/compiler/rustc_hir/src/hir.rs
@@ -1363,6 +1363,17 @@ impl AttributeExt for Attribute {
             _ => None,
         }
     }
+
+    fn is_proc_macro_attr(&self) -> bool {
+        matches!(
+            self,
+            Attribute::Parsed(
+                AttributeKind::ProcMacro(..)
+                    | AttributeKind::ProcMacroAttribute(..)
+                    | AttributeKind::ProcMacroDerive { .. }
+            )
+        )
+    }
 }
 
 // FIXME(fn_delegation): use function delegation instead of manually forwarding

diff --git a/compiler/rustc_metadata/src/rmeta/encoder.rs b/compiler/rustc_metadata/src/rmeta/encoder.rs
@@ -5,7 +5,7 @@ use std::io::{Read, Seek, Write};
 use std::path::{Path, PathBuf};
 use std::sync::Arc;
 
-use rustc_attr_data_structures::EncodeCrossCrate;
+use rustc_attr_data_structures::{AttributeKind, EncodeCrossCrate, find_attr};
 use rustc_data_structures::fx::{FxIndexMap, FxIndexSet};
 use rustc_data_structures::memmap::{Mmap, MmapMut};
 use rustc_data_structures::sync::{join, par_for_each_in};
@@ -1965,18 +1965,13 @@ impl<'a, 'tcx> EncodeContext<'a, 'tcx> {
                 // Proc-macros may have attributes like `#[allow_internal_unstable]`,
                 // so downstream crates need access to them.
                 let attrs = tcx.hir_attrs(proc_macro);
-                let macro_kind = if ast::attr::contains_name(attrs, sym::proc_macro) {
+                let macro_kind = if find_attr!(attrs, AttributeKind::ProcMacro(..)) {
                     MacroKind::Bang
-                } else if ast::attr::contains_name(attrs, sym::proc_macro_attribute) {
+                } else if find_attr!(attrs, AttributeKind::ProcMacroAttribute(..)) {
                     MacroKind::Attr
-                } else if let Some(attr) = ast::attr::find_by_name(attrs, sym::proc_macro_derive) {
-                    // This unwrap chain should have been checked by the proc-macro harness.
-                    name = attr.meta_item_list().unwrap()[0]
-                        .meta_item()
-                        .unwrap()
-                        .ident()
-                        .unwrap()
-                        .name;
+                } else if let Some(trait_name) = find_attr!(attrs, AttributeKind::ProcMacroDerive { trait_name, ..} => trait_name)
+                {
+                    name = *trait_name;
                     MacroKind::Derive
                 } else {
                     bug!("Unknown proc-macro type for item {:?}", id);

diff --git a/compiler/rustc_middle/src/ty/mod.rs b/compiler/rustc_middle/src/ty/mod.rs
@@ -2024,7 +2024,10 @@ impl<'tcx> TyCtxt<'tcx> {
             && let Some(def_id) = def_id.as_local()
             && let outer = self.def_span(def_id).ctxt().outer_expn_data()
             && matches!(outer.kind, ExpnKind::Macro(MacroKind::Derive, _))
-            && self.has_attr(outer.macro_def_id.unwrap(), sym::rustc_builtin_macro)
+            && find_attr!(
+                self.get_all_attrs(outer.macro_def_id.unwrap()),
+                AttributeKind::RustcBuiltinMacro { .. }
+            )
         {
             true
         } else {