resolve: Fix incorrect results of opt_def_kind query for some built-in macros

Previously it always returned `MacroKind::Bang` while some of those macros are actually attributes and derives

Author: petrochenkov

compiler/rustc_ast_lowering/src/item.rs

@@ -444,8 +444,8 @@ impl<'hir> LoweringContext<'_, 'hir> {
             ),
             ItemKind::MacroDef(MacroDef { ref body, macro_rules }) => {
                 let body = P(self.lower_mac_args(body));
-
-                hir::ItemKind::Macro(ast::MacroDef { body, macro_rules })
+                let macro_kind = self.resolver.decl_macro_kind(self.resolver.local_def_id(id));
+                hir::ItemKind::Macro(ast::MacroDef { body, macro_rules }, macro_kind)
             }
             ItemKind::MacCall(..) => {
                 panic!("`TyMac` should have been expanded by now")

compiler/rustc_ast_lowering/src/lib.rs

@@ -61,7 +61,7 @@ use rustc_session::lint::LintBuffer;
 use rustc_session::parse::feature_err;
 use rustc_session::utils::{FlattenNonterminals, NtToTokenstream};
 use rustc_session::Session;
-use rustc_span::hygiene::ExpnId;
+use rustc_span::hygiene::{ExpnId, MacroKind};
 use rustc_span::source_map::{respan, DesugaringKind};
 use rustc_span::symbol::{kw, sym, Ident, Symbol};
 use rustc_span::{Span, DUMMY_SP};
@@ -210,6 +210,8 @@ pub trait ResolverAstLowering {
         expn_id: ExpnId,
         span: Span,
     ) -> LocalDefId;
+
+    fn decl_macro_kind(&self, def_id: LocalDefId) -> MacroKind;
 }
 
 /// Context of `impl Trait` in code, which determines whether it is allowed in an HIR subtree,

compiler/rustc_hir/src/hir.rs

@@ -15,6 +15,7 @@ use rustc_data_structures::fx::FxHashMap;
 use rustc_data_structures::sorted_map::SortedMap;
 use rustc_index::vec::IndexVec;
 use rustc_macros::HashStable_Generic;
+use rustc_span::hygiene::MacroKind;
 use rustc_span::source_map::Spanned;
 use rustc_span::symbol::{kw, sym, Ident, Symbol};
 use rustc_span::{def_id::LocalDefId, BytePos, MultiSpan, Span, DUMMY_SP};
@@ -2803,7 +2804,7 @@ pub enum ItemKind<'hir> {
     /// A function declaration.
     Fn(FnSig<'hir>, Generics<'hir>, BodyId),
     /// A MBE macro definition (`macro_rules!` or `macro`).
-    Macro(ast::MacroDef),
+    Macro(ast::MacroDef, MacroKind),
     /// A module.
     Mod(Mod<'hir>),
     /// An external module, e.g. `extern { .. }`.

compiler/rustc_hir/src/intravisit.rs

@@ -575,7 +575,7 @@ pub fn walk_item<'v, V: Visitor<'v>>(visitor: &mut V, item: &'v Item<'v>) {
             item.span,
             item.hir_id(),
         ),
-        ItemKind::Macro(_) => {
+        ItemKind::Macro(..) => {
             visitor.visit_id(item.hir_id());
         }
         ItemKind::Mod(ref module) => {

compiler/rustc_hir_pretty/src/lib.rs

@@ -570,7 +570,7 @@ impl<'a> State<'a> {
                 self.end(); // need to close a box
                 self.ann.nested(self, Nested::Body(body));
             }
-            hir::ItemKind::Macro(ref macro_def) => {
+            hir::ItemKind::Macro(ref macro_def, _) => {
                 self.print_mac_def(macro_def, &item.ident, item.span, |state| {
                     state.print_visibility(&item.vis)
                 });

compiler/rustc_metadata/src/rmeta/encoder.rs

@@ -1406,7 +1406,7 @@ impl<'a, 'tcx> EncodeContext<'a, 'tcx> {
 
                 EntryKind::Fn(self.lazy(data))
             }
-            hir::ItemKind::Macro(ref macro_def) => {
+            hir::ItemKind::Macro(ref macro_def, _) => {
                 EntryKind::MacroDef(self.lazy(macro_def.clone()))
             }
             hir::ItemKind::Mod(ref m) => {

compiler/rustc_middle/src/hir/map/mod.rs

@@ -14,7 +14,6 @@ use rustc_hir::*;
 use rustc_index::vec::Idx;
 use rustc_middle::hir::nested_filter;
 use rustc_span::def_id::StableCrateId;
-use rustc_span::hygiene::MacroKind;
 use rustc_span::source_map::Spanned;
 use rustc_span::symbol::{kw, sym, Ident, Symbol};
 use rustc_span::Span;
@@ -232,7 +231,7 @@ impl<'hir> Map<'hir> {
                 ItemKind::Static(..) => DefKind::Static,
                 ItemKind::Const(..) => DefKind::Const,
                 ItemKind::Fn(..) => DefKind::Fn,
-                ItemKind::Macro(..) => DefKind::Macro(MacroKind::Bang),
+                ItemKind::Macro(_, macro_kind) => DefKind::Macro(macro_kind),
                 ItemKind::Mod(..) => DefKind::Mod,
                 ItemKind::OpaqueTy(..) => DefKind::OpaqueTy,
                 ItemKind::TyAlias(..) => DefKind::TyAlias,

compiler/rustc_passes/src/check_attr.rs

@@ -1951,7 +1951,7 @@ impl<'tcx> Visitor<'tcx> for CheckAttrVisitor<'tcx> {
         // Historically we've run more checks on non-exported than exported macros,
         // so this lets us continue to run them while maintaining backwards compatibility.
         // In the long run, the checks should be harmonized.
-        if let ItemKind::Macro(ref macro_def) = item.kind {
+        if let ItemKind::Macro(ref macro_def, _) = item.kind {
             let def_id = item.def_id.to_def_id();
             if macro_def.macro_rules && !self.tcx.has_attr(def_id, sym::macro_export) {
                 check_non_exported_macro_for_invalid_attrs(self.tcx, item);

compiler/rustc_privacy/src/lib.rs

@@ -564,7 +564,7 @@ impl<'tcx> EmbargoVisitor<'tcx> {
             // privacy and mark them reachable.
             DefKind::Macro(_) => {
                 let item = self.tcx.hir().expect_item(def_id);
-                if let hir::ItemKind::Macro(MacroDef { macro_rules: false, .. }) = item.kind {
+                if let hir::ItemKind::Macro(MacroDef { macro_rules: false, .. }, _) = item.kind {
                     if vis.is_accessible_from(module.to_def_id(), self.tcx) {
                         self.update(def_id, level);
                     }
@@ -686,7 +686,7 @@ impl<'tcx> Visitor<'tcx> for EmbargoVisitor<'tcx> {
                     }
                 }
             }
-            hir::ItemKind::Macro(ref macro_def) => {
+            hir::ItemKind::Macro(ref macro_def, _) => {
                 self.update_reachability_from_macro(item.def_id, macro_def);
             }
             hir::ItemKind::ForeignMod { items, .. } => {

compiler/rustc_resolve/src/lib.rs

@@ -990,6 +990,9 @@ pub struct Resolver<'a> {
     crate_loader: CrateLoader<'a>,
     macro_names: FxHashSet<Ident>,
     builtin_macros: FxHashMap<Symbol, BuiltinMacroState>,
+    /// A small map keeping true kinds of built-in macros that appear to be fn-like on
+    /// the surface (`macro` items in libcore), but are actually attributes or derives.
+    builtin_macro_kinds: FxHashMap<LocalDefId, MacroKind>,
     registered_attrs: FxHashSet<Ident>,
     registered_tools: RegisteredTools,
     macro_use_prelude: FxHashMap<Symbol, &'a NameBinding<'a>>,
@@ -1261,6 +1264,10 @@ impl ResolverAstLowering for Resolver<'_> {
 
         def_id
     }
+
+    fn decl_macro_kind(&self, def_id: LocalDefId) -> MacroKind {
+        self.builtin_macro_kinds.get(&def_id).copied().unwrap_or(MacroKind::Bang)
+    }
 }
 
 impl<'a> Resolver<'a> {
@@ -1381,6 +1388,7 @@ impl<'a> Resolver<'a> {
             crate_loader: CrateLoader::new(session, metadata_loader, crate_name),
             macro_names: FxHashSet::default(),
             builtin_macros: Default::default(),
+            builtin_macro_kinds: Default::default(),
             registered_attrs,
             registered_tools,
             macro_use_prelude: FxHashMap::default(),