Split register_tool into register_attribute_tool and register_lint_tool

compiler/rustc_ast_lowering/src/lib.rs

@@ -291,7 +291,7 @@ impl<'a, 'hir> LoweringContext<'a, 'hir> {
             attribute_parser: AttributeParser::new(
                 tcx.sess,
                 tcx.features(),
-                tcx.registered_tools(()),
+                tcx.registered_attr_tools(()),
                 ShouldEmit::ErrorsAndLints { recovery: Recovery::Allowed },
             ),
             delayed_lints: Vec::new(),

compiler/rustc_ast_passes/src/feature_gate.rs

@@ -634,7 +634,7 @@ fn maybe_stage_features(sess: &Session, features: &Features, krate: &ast::Crate)
     let mut errored = false;
 
     if let Some(Attribute::Parsed(AttributeKind::Feature(feature_idents, first_span))) =
-        AttributeParser::parse_limited(sess, &krate.attrs, &[sym::feature])
+        AttributeParser::parse_limited_sym(sess, &krate.attrs, &[sym::feature])
     {
         // `feature(...)` used on non-nightly. This is definitely an error.
         let mut err = diagnostics::FeatureOnNonNightly {

compiler/rustc_attr_parsing/src/attributes/codegen_attrs.rs

@@ -280,7 +280,7 @@ impl AttributeParser for NakedParser {
 
         let span = self.span?;
 
-        let Some(tools) = cx.tools else {
+        let Some(tools) = cx.attr_tools else {
             unreachable!("tools required while parsing attributes");
         };
 

compiler/rustc_attr_parsing/src/attributes/crate_level.rs

@@ -1,11 +1,12 @@
+use rustc_data_structures::fx::FxIndexSet;
 use rustc_feature::AttributeStability;
 use rustc_hir::attrs::{CrateType, WindowsSubsystemKind};
 use rustc_session::lint::builtin::UNKNOWN_CRATE_TYPES;
 use rustc_span::Symbol;
 use rustc_span::edit_distance::find_best_match_for_name_with_substrings;
 
 use super::prelude::*;
-use crate::diagnostics::{UnknownCrateTypes, UnknownCrateTypesSuggestion};
+use crate::diagnostics::{ToolReserved, UnknownCrateTypes, UnknownCrateTypesSuggestion};
 
 pub(crate) struct CrateNameParser;
 
@@ -317,49 +318,87 @@ impl CombineAttributeParser for FeatureParser {
     }
 }
 
-pub(crate) struct RegisterToolParser;
+#[derive(Default)]
+pub(crate) struct RegisterToolParser {
+    attr_tools: FxIndexSet<Ident>,
+    lint_tools: FxIndexSet<Ident>,
+}
 
-impl CombineAttributeParser for RegisterToolParser {
-    const PATH: &[Symbol] = &[sym::register_tool];
-    type Item = Ident;
-    const CONVERT: ConvertFn<Self::Item> = |tools, _span| AttributeKind::RegisterTool(tools);
-    const ALLOWED_TARGETS: AllowedTargets<'_> = AllowedTargets::AllowList(&[Allow(Target::Crate)]);
-    const TEMPLATE: AttributeTemplate = template!(List: &["tool1, tool2, ..."]);
-    const STABILITY: AttributeStability = unstable!(register_tool);
+fn parse_register_tool(
+    tools: &mut [&mut FxIndexSet<Ident>],
+    cx: &mut AcceptContext<'_, '_>,
+    args: &ArgParser,
+) {
+    let Some(list) = cx.expect_list(args, cx.attr_span) else {
+        return;
+    };
+
+    if list.is_empty() {
+        let attr_span = cx.attr_span;
+        cx.adcx().warn_empty_attribute(attr_span);
+    }
 
-    fn extend(
-        cx: &mut AcceptContext<'_, '_>,
-        args: &ArgParser,
-    ) -> impl IntoIterator<Item = Self::Item> {
-        let Some(list) = cx.expect_list(args, cx.attr_span) else {
-            return Vec::new();
+    for elem in list.mixed() {
+        let Some(elem) = elem.meta_item() else {
+            cx.adcx().expected_identifier(elem.span());
+            continue;
+        };
+        let Some(()) = cx.expect_no_args(elem.args()) else {
+            continue;
         };
 
-        if list.is_empty() {
-            let attr_span = cx.attr_span;
-            cx.adcx().warn_empty_attribute(attr_span);
+        let path = elem.path();
+        let Some(ident) = path.word() else {
+            cx.adcx().expected_identifier(path.span());
+            continue;
+        };
+
+        if ident.name == sym::rustc {
+            cx.should_emit
+                .emit_err(cx.dcx().create_err(ToolReserved { span: ident.span, tool: ident }));
+            continue;
         }
 
-        let mut res = Vec::new();
+        for tools in tools.iter_mut() {
+            tools.insert(ident);
+        }
+    }
+}
 
-        for elem in list.mixed() {
-            let Some(elem) = elem.meta_item() else {
-                cx.adcx().expected_identifier(elem.span());
-                continue;
-            };
-            let Some(()) = cx.expect_no_args(elem.args()) else {
-                continue;
-            };
+impl AttributeParser for RegisterToolParser {
+    const ATTRIBUTES: AcceptMapping<Self> = &[
+        (
+            &[sym::register_tool],
+            template!(List: &["tool1, tool2, ..."]),
+            unstable!(register_tool),
+            |this, cx, args| {
+                parse_register_tool(&mut [&mut this.attr_tools, &mut this.lint_tools], cx, args)
+            },
+        ),
+        (
+            &[sym::register_attribute_tool],
+            template!(List: &["tool1, tool2, ..."]),
+            unstable!(register_tool),
+            |this, cx, args| parse_register_tool(&mut [&mut this.attr_tools], cx, args),
+        ),
+        (
+            &[sym::register_lint_tool],
+            template!(List: &["tool1, tool2, ..."]),
+            unstable!(register_tool),
+            |this, cx, args| parse_register_tool(&mut [&mut this.lint_tools], cx, args),
+        ),
+    ];
 
-            let path = elem.path();
-            let Some(ident) = path.word() else {
-                cx.adcx().expected_identifier(path.span());
-                continue;
-            };
+    const ALLOWED_TARGETS: AllowedTargets<'_> = AllowedTargets::AllowList(&[Allow(Target::Crate)]);
 
-            res.push(ident);
+    fn finalize(self, _cx: &FinalizeContext<'_, '_>) -> Option<AttributeKind> {
+        if self.attr_tools.is_empty() && self.lint_tools.is_empty() {
+            None
+        } else {
+            Some(AttributeKind::RegisterTool {
+                attr_tools: self.attr_tools.into_iter().collect(),
+                lint_tools: self.lint_tools.into_iter().collect(),
+            })
         }
-
-        res
     }
 }

compiler/rustc_attr_parsing/src/context.rs

@@ -174,6 +174,7 @@ attribute_parsers!(
         OnUnknownParser,
         OnUnmatchedArgsParser,
         OpaqueParser,
+        RegisterToolParser,
         RustcAlignParser,
         RustcAlignStaticParser,
         RustcCguTestAttributeParser,
@@ -188,7 +189,6 @@ attribute_parsers!(
         Combine<FeatureParser>,
         Combine<ForceTargetFeatureParser>,
         Combine<LinkParser>,
-        Combine<RegisterToolParser>,
         Combine<ReprParser>,
         Combine<RustcAllowConstFnUnstableParser>,
         Combine<RustcCleanParser>,

compiler/rustc_attr_parsing/src/diagnostics.rs

@@ -1,7 +1,7 @@
 use rustc_errors::{Applicability, DiagArgValue, E0232, E0264, MultiSpan};
 use rustc_hir::AttrPath;
 use rustc_macros::{Diagnostic, Subdiagnostic};
-use rustc_span::{Span, Symbol};
+use rustc_span::{Ident, Span, Symbol};
 
 #[derive(Diagnostic)]
 #[diag("`{$name}` attribute cannot be used at crate level")]
@@ -828,3 +828,11 @@ pub(crate) struct UnknownExternLangItem {
     pub span: Span,
     pub lang_item: Symbol,
 }
+
+#[derive(Diagnostic)]
+#[diag("tool `{$tool}` is reserved and cannot be registered")]
+pub(crate) struct ToolReserved {
+    #[primary_span]
+    pub(crate) span: Span,
+    pub(crate) tool: Ident,
+}

compiler/rustc_attr_parsing/src/interface.rs

@@ -38,15 +38,15 @@ pub struct EmitAttribute(
 /// Context created once, for example as part of the ast lowering
 /// context, through which all attributes can be lowered.
 pub struct AttributeParser<'sess> {
-    pub(crate) tools: Option<&'sess RegisteredTools>,
+    pub(crate) attr_tools: Option<&'sess RegisteredTools>,
     pub(crate) features: Option<&'sess Features>,
     pub(crate) sess: &'sess Session,
     pub(crate) should_emit: ShouldEmit,
 
-    /// *Only* parse attributes with this symbol.
+    /// *Only* parse attributes that passes this filter.
     ///
-    /// Used in cases where we want the lowering infrastructure for parse just a single attribute.
-    parse_only: Option<&'static [Symbol]>,
+    /// Used in cases where we want the lowering infrastructure for parse just limited attributes.
+    parse_filter: Option<&'sess dyn Fn(&ast::Attribute) -> bool>,
 }
 
 impl<'sess> AttributeParser<'sess> {
@@ -58,8 +58,8 @@ impl<'sess> AttributeParser<'sess> {
     /// `rustc_ast_lowering`. Some attributes require access to features to parse, which would
     /// crash if you tried to do so through [`parse_limited`](Self::parse_limited).
     ///
-    /// To make sure use is limited, supply a `Symbol` you'd like to parse. Only attributes with
-    /// that symbol are picked out of the list of instructions and parsed. Those are returned.
+    /// To make sure use is limited, supply a filter. Only attributes that passes the filter are
+    /// picked out of the list of instructions and parsed. Those are returned.
     ///
     /// No diagnostics will be emitted when parsing limited. Lints are not emitted at all, while
     /// errors will be emitted as a delayed bugs. in other words, we *expect* attributes parsed
@@ -69,42 +69,48 @@ impl<'sess> AttributeParser<'sess> {
     pub fn parse_limited(
         sess: &'sess Session,
         attrs: &[ast::Attribute],
-        sym: &'static [Symbol],
+        parse_filter: &dyn Fn(&ast::Attribute) -> bool,
     ) -> Option<Attribute> {
         Self::parse_limited_should_emit(
             sess,
             attrs,
-            sym,
+            parse_filter,
             // Because we're not emitting warnings/errors, the target should not matter
             DUMMY_SP,
-            CRATE_NODE_ID,
-            Target::Crate,
             None,
             ShouldEmit::Nothing,
         )
     }
 
+    /// This does the same as `parse_limited`, except that it takes a fixed symbol instead of a
+    /// filter.
+    pub fn parse_limited_sym(
+        sess: &'sess Session,
+        attrs: &[ast::Attribute],
+        sym: &'static [Symbol],
+    ) -> Option<Attribute> {
+        Self::parse_limited(sess, attrs, &|attr| attr.path_matches(sym))
+    }
+
     /// This does the same as `parse_limited`, except it has a `should_emit` parameter which allows it to emit errors.
     /// Usually you want `parse_limited`, which emits no errors.
     ///
     /// Due to this function not taking in `RegisteredTools`, *do not* use this for parsing any lint attributes
     pub fn parse_limited_should_emit(
         sess: &'sess Session,
         attrs: &[ast::Attribute],
-        sym: &'static [Symbol],
+        parse_filter: &dyn Fn(&ast::Attribute) -> bool,
         target_span: Span,
-        target_node_id: NodeId,
-        target: Target,
         features: Option<&'sess Features>,
         should_emit: ShouldEmit,
     ) -> Option<Attribute> {
         let mut parsed = Self::parse_limited_all(
             sess,
             attrs,
-            Some(sym),
-            target,
+            Some(parse_filter),
+            Target::Crate,
             target_span,
-            target_node_id,
+            CRATE_NODE_ID,
             features,
             should_emit,
             None,
@@ -113,25 +119,45 @@ impl<'sess> AttributeParser<'sess> {
         parsed.pop()
     }
 
+    /// This does the same as `parse_limited_should_emit`, except that it takes a fixed symbol
+    /// instead of a filter.
+    pub fn parse_limited_sym_should_emit(
+        sess: &'sess Session,
+        attrs: &[ast::Attribute],
+        sym: &'static [Symbol],
+        target_span: Span,
+        features: Option<&'sess Features>,
+        should_emit: ShouldEmit,
+    ) -> Option<Attribute> {
+        Self::parse_limited_should_emit(
+            sess,
+            attrs,
+            &|attr| attr.path_matches(sym),
+            target_span,
+            features,
+            should_emit,
+        )
+    }
+
     /// This method allows you to parse a list of attributes *before* `rustc_ast_lowering`.
     /// This can be used for attributes that would be removed before `rustc_ast_lowering`, such as attributes on macro calls.
     ///
     /// Try to use this as little as possible. Attributes *should* be lowered during
     /// `rustc_ast_lowering`. Some attributes require access to features to parse, which would
     /// crash if you tried to do so through [`parse_limited_all`](Self::parse_limited_all).
-    /// Therefore, if `parse_only` is None, then features *must* be provided.
+    /// Therefore, if `parse_filter` is None, then features *must* be provided.
     pub fn parse_limited_all(
         sess: &'sess Session,
         attrs: &[ast::Attribute],
-        parse_only: Option<&'static [Symbol]>,
+        parse_filter: Option<&dyn Fn(&ast::Attribute) -> bool>,
         target: Target,
         target_span: Span,
         target_node_id: NodeId,
         features: Option<&'sess Features>,
         should_emit: ShouldEmit,
-        tools: Option<&'sess RegisteredTools>,
+        attr_tools: Option<&'sess RegisteredTools>,
     ) -> Vec<Attribute> {
-        let mut p = Self { features, tools, parse_only, sess, should_emit };
+        let mut p = AttributeParser { features, attr_tools, parse_filter, sess, should_emit };
         p.parse_attribute_list(
             attrs,
             target_span,
@@ -210,7 +236,7 @@ impl<'sess> AttributeParser<'sess> {
         parse_fn: fn(cx: &mut AcceptContext<'_, '_>, item: &I) -> T,
         template: &AttributeTemplate,
     ) -> T {
-        let mut parser = Self { features, tools: None, parse_only: None, sess, should_emit };
+        let mut parser = Self { features, attr_tools: None, parse_filter: None, sess, should_emit };
         let mut emit_lint = |lint_id: LintId, span: MultiSpan, kind: EmitAttribute| {
             sess.psess.dyn_buffer_lint_sess(lint_id.lint, span, target_node_id, kind.0)
         };
@@ -250,10 +276,16 @@ impl<'sess> AttributeParser<'sess> {
     pub fn new(
         sess: &'sess Session,
         features: &'sess Features,
-        tools: &'sess RegisteredTools,
+        attr_tools: &'sess RegisteredTools,
         should_emit: ShouldEmit,
     ) -> Self {
-        Self { features: Some(features), tools: Some(tools), parse_only: None, sess, should_emit }
+        Self {
+            features: Some(features),
+            attr_tools: Some(attr_tools),
+            parse_filter: None,
+            sess,
+            should_emit,
+        }
     }
 
     pub(crate) fn sess(&self) -> &'sess Session {
@@ -297,8 +329,8 @@ impl<'sess> AttributeParser<'sess> {
 
         for attr in attrs {
             // If we're only looking for a single attribute, skip all the ones we don't care about.
-            if let Some(expected) = self.parse_only {
-                if !attr.path_matches(expected) {
+            if let Some(filter) = self.parse_filter {
+                if !filter(attr) {
                     continue;
                 }
             }

compiler/rustc_builtin_macros/src/deriving/generic/mod.rs

@@ -493,7 +493,7 @@ impl<'a> TraitDef<'a> {
         match item {
             Annotatable::Item(item) => {
                 let is_packed = matches!(
-                    AttributeParser::parse_limited(cx.sess, &item.attrs, &[sym::repr]),
+                    AttributeParser::parse_limited_sym(cx.sess, &item.attrs, &[sym::repr]),
                     Some(Attribute::Parsed(AttributeKind::Repr { reprs, .. })) if reprs.iter().any(|(x, _)| matches!(x, ReprPacked(..)))
                 );
 

compiler/rustc_builtin_macros/src/proc_macro_harness.rs

@@ -100,7 +100,7 @@ impl<'a> CollectProcMacros<'a> {
         attr: &'a ast::Attribute,
     ) {
         let Some(rustc_hir::Attribute::Parsed(AttributeKind::ProcMacroDerive { .. })) =
-            AttributeParser::parse_limited(
+            AttributeParser::parse_limited_sym(
                 self.session,
                 slice::from_ref(attr),
                 &[sym::proc_macro_derive],