out_of_scope_macro_calls: Detect calls inside attributes more precisely

Author: petrochenkov

compiler/rustc_resolve/src/def_collector.rs

@@ -8,22 +8,25 @@ use rustc_hir::def_id::LocalDefId;
 use rustc_span::hygiene::LocalExpnId;
 use rustc_span::symbol::{kw, sym, Symbol};
 use rustc_span::Span;
+use std::mem;
 use tracing::debug;
 
 pub(crate) fn collect_definitions(
     resolver: &mut Resolver<'_, '_>,
     fragment: &AstFragment,
     expansion: LocalExpnId,
 ) {
-    let (parent_def, impl_trait_context) = resolver.invocation_parents[&expansion];
-    fragment.visit_with(&mut DefCollector { resolver, parent_def, expansion, impl_trait_context });
+    let (parent_def, impl_trait_context, in_attr) = resolver.invocation_parents[&expansion];
+    let mut visitor = DefCollector { resolver, parent_def, expansion, impl_trait_context, in_attr };
+    fragment.visit_with(&mut visitor);
 }
 
 /// Creates `DefId`s for nodes in the AST.
 struct DefCollector<'a, 'b, 'tcx> {
     resolver: &'a mut Resolver<'b, 'tcx>,
     parent_def: LocalDefId,
     impl_trait_context: ImplTraitContext,
+    in_attr: bool,
     expansion: LocalExpnId,
 }
 
@@ -53,7 +56,7 @@ impl<'a, 'b, 'tcx> DefCollector<'a, 'b, 'tcx> {
     }
 
     fn with_parent<F: FnOnce(&mut Self)>(&mut self, parent_def: LocalDefId, f: F) {
-        let orig_parent_def = std::mem::replace(&mut self.parent_def, parent_def);
+        let orig_parent_def = mem::replace(&mut self.parent_def, parent_def);
         f(self);
         self.parent_def = orig_parent_def;
     }
@@ -63,7 +66,7 @@ impl<'a, 'b, 'tcx> DefCollector<'a, 'b, 'tcx> {
         impl_trait_context: ImplTraitContext,
         f: F,
     ) {
-        let orig_itc = std::mem::replace(&mut self.impl_trait_context, impl_trait_context);
+        let orig_itc = mem::replace(&mut self.impl_trait_context, impl_trait_context);
         f(self);
         self.impl_trait_context = orig_itc;
     }
@@ -105,8 +108,10 @@ impl<'a, 'b, 'tcx> DefCollector<'a, 'b, 'tcx> {
 
     fn visit_macro_invoc(&mut self, id: NodeId) {
         let id = id.placeholder_to_expn_id();
-        let old_parent =
-            self.resolver.invocation_parents.insert(id, (self.parent_def, self.impl_trait_context));
+        let old_parent = self
+            .resolver
+            .invocation_parents
+            .insert(id, (self.parent_def, self.impl_trait_context, self.in_attr));
         assert!(old_parent.is_none(), "parent `LocalDefId` is reset for an invocation");
     }
 }
@@ -413,4 +418,10 @@ impl<'a, 'b, 'tcx> visit::Visitor<'a> for DefCollector<'a, 'b, 'tcx> {
             visit::walk_crate(self, krate)
         }
     }
+
+    fn visit_attribute(&mut self, attr: &'a Attribute) -> Self::Result {
+        let orig_in_attr = mem::replace(&mut self.in_attr, true);
+        visit::walk_attribute(self, attr);
+        self.in_attr = orig_in_attr;
+    }
 }

compiler/rustc_resolve/src/lib.rs

@@ -1139,7 +1139,7 @@ pub struct Resolver<'a, 'tcx> {
     /// When collecting definitions from an AST fragment produced by a macro invocation `ExpnId`
     /// we know what parent node that fragment should be attached to thanks to this table,
     /// and how the `impl Trait` fragments were introduced.
-    invocation_parents: FxHashMap<LocalExpnId, (LocalDefId, ImplTraitContext)>,
+    invocation_parents: FxHashMap<LocalExpnId, (LocalDefId, ImplTraitContext, bool /*in_attr*/)>,
 
     /// Some way to know that we are in a *trait* impl in `visit_assoc_item`.
     /// FIXME: Replace with a more general AST map (together with some other fields).
@@ -1371,7 +1371,8 @@ impl<'a, 'tcx> Resolver<'a, 'tcx> {
         node_id_to_def_id.insert(CRATE_NODE_ID, crate_feed);
 
         let mut invocation_parents = FxHashMap::default();
-        invocation_parents.insert(LocalExpnId::ROOT, (CRATE_DEF_ID, ImplTraitContext::Existential));
+        invocation_parents
+            .insert(LocalExpnId::ROOT, (CRATE_DEF_ID, ImplTraitContext::Existential, false));
 
         let mut extern_prelude: FxHashMap<Ident, ExternPreludeEntry<'_>> = tcx
             .sess

compiler/rustc_resolve/src/macros.rs

@@ -297,11 +297,12 @@ impl<'a, 'tcx> ResolverExpand for Resolver<'a, 'tcx> {
             .invocation_parents
             .get(&invoc_id)
             .or_else(|| self.invocation_parents.get(&eager_expansion_root))
-            .map(|&(mod_def_id, _)| mod_def_id)
-            .filter(|&mod_def_id| {
-                invoc.fragment_kind == AstFragmentKind::Expr
+            .filter(|&&(mod_def_id, _, in_attr)| {
+                in_attr
+                    && invoc.fragment_kind == AstFragmentKind::Expr
                     && self.tcx.def_kind(mod_def_id) == DefKind::Mod
-            });
+            })
+            .map(|&(mod_def_id, ..)| mod_def_id);
         let (ext, res) = self.smart_resolve_macro_path(
             path,
             kind,

tests/ui/macros/out-of-scope-calls-false-positives.rs

@@ -0,0 +1,10 @@
+//@ check-pass
+//@ needs-asm-support
+
+macro_rules! mac { () => { "" } }
+macro_rules! mac2 { () => { "auxiliary/issue-40469.rs" } }
+
+std::arch::global_asm!(mac!()); // OK
+include!(mac2!()); // OK
+
+fn main() {}