Un📦ing the Resolver

compiler/rustc_interface/src/interface.rs

@@ -1,4 +1,3 @@
-pub use crate::passes::BoxedResolver;
 use crate::util;
 
 use rustc_ast::token;

compiler/rustc_interface/src/passes.rs

@@ -23,9 +23,9 @@ use rustc_parse::{parse_crate_from_file, parse_crate_from_source_str, validate_a
 use rustc_passes::{self, hir_stats, layout_test};
 use rustc_plugin_impl as plugin;
 use rustc_query_impl::{OnDiskCache, Queries as TcxQueries};
-use rustc_resolve::{Resolver, ResolverArenas};
+use rustc_resolve::Resolver;
 use rustc_session::config::{CrateType, Input, OutputFilenames, OutputType};
-use rustc_session::cstore::{CrateStoreDyn, MetadataLoader, MetadataLoaderDyn, Untracked};
+use rustc_session::cstore::{CrateStoreDyn, MetadataLoader, Untracked};
 use rustc_session::output::filename_for_input;
 use rustc_session::search_paths::PathKind;
 use rustc_session::{Limit, Session};
@@ -37,9 +37,7 @@ use rustc_trait_selection::traits;
 use std::any::Any;
 use std::ffi::OsString;
 use std::io::{self, BufWriter, Write};
-use std::marker::PhantomPinned;
 use std::path::{Path, PathBuf};
-use std::pin::Pin;
 use std::sync::{Arc, LazyLock};
 use std::{env, fs, iter};
 
@@ -73,84 +71,6 @@ fn count_nodes(krate: &ast::Crate) -> usize {
     counter.count
 }
 
-pub use boxed_resolver::BoxedResolver;
-mod boxed_resolver {
-    use super::*;
-
-    pub struct BoxedResolver(Pin<Box<BoxedResolverInner>>);
-
-    struct BoxedResolverInner {
-        session: Lrc<Session>,
-        resolver_arenas: Option<ResolverArenas<'static>>,
-        resolver: Option<Resolver<'static>>,
-        _pin: PhantomPinned,
-    }
-
-    // Note: Drop order is important to prevent dangling references. Resolver must be dropped first,
-    // then resolver_arenas and session.
-    impl Drop for BoxedResolverInner {
-        fn drop(&mut self) {
-            self.resolver.take();
-            self.resolver_arenas.take();
-        }
-    }
-
-    impl BoxedResolver {
-        pub(super) fn new(
-            session: Lrc<Session>,
-            make_resolver: impl for<'a> FnOnce(&'a Session, &'a ResolverArenas<'a>) -> Resolver<'a>,
-        ) -> BoxedResolver {
-            let mut boxed_resolver = Box::new(BoxedResolverInner {
-                session,
-                resolver_arenas: Some(Resolver::arenas()),
-                resolver: None,
-                _pin: PhantomPinned,
-            });
-            // SAFETY: `make_resolver` takes a resolver arena with an arbitrary lifetime and
-            // returns a resolver with the same lifetime as the arena. We ensure that the arena
-            // outlives the resolver in the drop impl and elsewhere so these transmutes are sound.
-            unsafe {
-                let resolver = make_resolver(
-                    std::mem::transmute::<&Session, &Session>(&boxed_resolver.session),
-                    std::mem::transmute::<&ResolverArenas<'_>, &ResolverArenas<'_>>(
-                        boxed_resolver.resolver_arenas.as_ref().unwrap(),
-                    ),
-                );
-                boxed_resolver.resolver = Some(resolver);
-                BoxedResolver(Pin::new_unchecked(boxed_resolver))
-            }
-        }
-
-        pub fn access<F: for<'a> FnOnce(&mut Resolver<'a>) -> R, R>(&mut self, f: F) -> R {
-            // SAFETY: The resolver doesn't need to be pinned.
-            let mut resolver = unsafe {
-                self.0.as_mut().map_unchecked_mut(|boxed_resolver| &mut boxed_resolver.resolver)
-            };
-            f((&mut *resolver).as_mut().unwrap())
-        }
-
-        pub fn into_outputs(mut self) -> ty::ResolverOutputs {
-            // SAFETY: The resolver doesn't need to be pinned.
-            let mut resolver = unsafe {
-                self.0.as_mut().map_unchecked_mut(|boxed_resolver| &mut boxed_resolver.resolver)
-            };
-            resolver.take().unwrap().into_outputs()
-        }
-    }
-}
-
-pub fn create_resolver(
-    sess: Lrc<Session>,
-    metadata_loader: Box<MetadataLoaderDyn>,
-    krate: &ast::Crate,
-    crate_name: Symbol,
-) -> BoxedResolver {
-    trace!("create_resolver");
-    BoxedResolver::new(sess, move |sess, resolver_arenas| {
-        Resolver::new(sess, krate, crate_name, metadata_loader, resolver_arenas)
-    })
-}
-
 pub fn register_plugins<'a>(
     sess: &'a Session,
     metadata_loader: &'a dyn MetadataLoader,
@@ -256,7 +176,7 @@ pub fn configure_and_expand(
     lint_store: &LintStore,
     mut krate: ast::Crate,
     crate_name: Symbol,
-    resolver: &mut Resolver<'_>,
+    resolver: &mut Resolver<'_, '_>,
 ) -> Result<ast::Crate> {
     trace!("configure_and_expand");
     pre_expansion_lint(sess, lint_store, resolver.registered_tools(), &krate, crate_name);

compiler/rustc_interface/src/queries.rs

@@ -1,6 +1,6 @@
 use crate::errors::{FailedWritingFile, RustcErrorFatal, RustcErrorUnexpectedAnnotation};
 use crate::interface::{Compiler, Result};
-use crate::passes::{self, BoxedResolver};
+use crate::passes;
 
 use rustc_ast as ast;
 use rustc_codegen_ssa::traits::CodegenBackend;
@@ -15,6 +15,7 @@ use rustc_middle::arena::Arena;
 use rustc_middle::dep_graph::DepGraph;
 use rustc_middle::ty::{self, GlobalCtxt, TyCtxt};
 use rustc_query_impl::Queries as TcxQueries;
+use rustc_resolve::Resolver;
 use rustc_session::config::{self, OutputFilenames, OutputType};
 use rustc_session::{output::find_crate_name, Session};
 use rustc_span::symbol::sym;
@@ -87,7 +88,6 @@ pub struct Queries<'tcx> {
     parse: Query<ast::Crate>,
     crate_name: Query<Symbol>,
     register_plugins: Query<(ast::Crate, Lrc<LintStore>)>,
-    expansion: Query<(Lrc<ast::Crate>, BoxedResolver, Lrc<LintStore>)>,
     dep_graph: Query<DepGraph>,
     // This just points to what's in `gcx_cell`.
     gcx: Query<&'tcx GlobalCtxt<'tcx>>,
@@ -106,7 +106,6 @@ impl<'tcx> Queries<'tcx> {
             parse: Default::default(),
             crate_name: Default::default(),
             register_plugins: Default::default(),
-            expansion: Default::default(),
             dep_graph: Default::default(),
             gcx: Default::default(),
             ongoing_codegen: Default::default(),
@@ -168,28 +167,6 @@ impl<'tcx> Queries<'tcx> {
         })
     }
 
-    pub fn expansion(
-        &self,
-    ) -> Result<QueryResult<'_, (Lrc<ast::Crate>, BoxedResolver, Lrc<LintStore>)>> {
-        trace!("expansion");
-        self.expansion.compute(|| {
-            let crate_name = *self.crate_name()?.borrow();
-            let (krate, lint_store) = self.register_plugins()?.steal();
-            let _timer = self.session().timer("configure_and_expand");
-            let sess = self.session();
-            let mut resolver = passes::create_resolver(
-                sess.clone(),
-                self.codegen_backend().metadata_loader(),
-                &krate,
-                crate_name,
-            );
-            let krate = resolver.access(|resolver| {
-                passes::configure_and_expand(sess, &lint_store, krate, crate_name, resolver)
-            })?;
-            Ok((Lrc::new(krate), resolver, lint_store))
-        })
-    }
-
     fn dep_graph(&self) -> Result<QueryResult<'_, DepGraph>> {
         self.dep_graph.compute(|| {
             let sess = self.session();
@@ -209,13 +186,34 @@ impl<'tcx> Queries<'tcx> {
     pub fn global_ctxt(&'tcx self) -> Result<QueryResult<'_, &'tcx GlobalCtxt<'tcx>>> {
         self.gcx.compute(|| {
             let crate_name = *self.crate_name()?.borrow();
-            let (krate, resolver, lint_store) = self.expansion()?.steal();
+            let (krate, lint_store) = self.register_plugins()?.steal();
+            let (krate, resolver_outputs) = {
+                let _timer = self.session().timer("configure_and_expand");
+                let sess = self.session();
+
+                let arenas = Resolver::arenas();
+                let mut resolver = Resolver::new(
+                    sess,
+                    &krate,
+                    crate_name,
+                    self.codegen_backend().metadata_loader(),
+                    &arenas,
+                );
+                let krate = passes::configure_and_expand(
+                    sess,
+                    &lint_store,
+                    krate,
+                    crate_name,
+                    &mut resolver,
+                )?;
+                (Lrc::new(krate), resolver.into_outputs())
+            };
 
             let ty::ResolverOutputs {
                 untracked,
                 global_ctxt: untracked_resolutions,
                 ast_lowering: untracked_resolver_for_lowering,
-            } = resolver.into_outputs();
+            } = resolver_outputs;
 
             let gcx = passes::create_global_ctxt(
                 self.compiler,

compiler/rustc_resolve/src/build_reduced_graph.rs

@@ -65,7 +65,7 @@ impl<'a, Id: Into<DefId>> ToNameBinding<'a> for (Res, ty::Visibility<Id>, Span,
     }
 }
 
-impl<'a> Resolver<'a> {
+impl<'a, 'tcx> Resolver<'a, 'tcx> {
     /// Defines `name` in namespace `ns` of module `parent` to be `def` if it is not yet defined;
     /// otherwise, reports an error.
     pub(crate) fn define<T>(&mut self, parent: Module<'a>, ident: Ident, ns: Namespace, def: T)
@@ -214,18 +214,18 @@ impl<'a> Resolver<'a> {
     }
 }
 
-struct BuildReducedGraphVisitor<'a, 'b> {
-    r: &'b mut Resolver<'a>,
+struct BuildReducedGraphVisitor<'a, 'b, 'tcx> {
+    r: &'b mut Resolver<'a, 'tcx>,
     parent_scope: ParentScope<'a>,
 }
 
-impl<'a> AsMut<Resolver<'a>> for BuildReducedGraphVisitor<'a, '_> {
-    fn as_mut(&mut self) -> &mut Resolver<'a> {
+impl<'a, 'tcx> AsMut<Resolver<'a, 'tcx>> for BuildReducedGraphVisitor<'a, '_, 'tcx> {
+    fn as_mut(&mut self) -> &mut Resolver<'a, 'tcx> {
         self.r
     }
 }
 
-impl<'a, 'b> BuildReducedGraphVisitor<'a, 'b> {
+impl<'a, 'b, 'tcx> BuildReducedGraphVisitor<'a, 'b, 'tcx> {
     fn resolve_visibility(&mut self, vis: &ast::Visibility) -> ty::Visibility {
         self.try_resolve_visibility(vis, true).unwrap_or_else(|err| {
             self.r.report_vis_error(err);
@@ -1315,7 +1315,7 @@ macro_rules! method {
     };
 }
 
-impl<'a, 'b> Visitor<'b> for BuildReducedGraphVisitor<'a, 'b> {
+impl<'a, 'b, 'tcx> Visitor<'b> for BuildReducedGraphVisitor<'a, 'b, 'tcx> {
     method!(visit_expr: ast::Expr, ast::ExprKind::MacCall, walk_expr);
     method!(visit_pat: ast::Pat, ast::PatKind::MacCall, walk_pat);
     method!(visit_ty: ast::Ty, ast::TyKind::MacCall, walk_ty);

compiler/rustc_resolve/src/check_unused.rs

@@ -49,16 +49,16 @@ impl<'a> UnusedImport<'a> {
     }
 }
 
-struct UnusedImportCheckVisitor<'a, 'b> {
-    r: &'a mut Resolver<'b>,
+struct UnusedImportCheckVisitor<'a, 'b, 'tcx> {
+    r: &'a mut Resolver<'b, 'tcx>,
     /// All the (so far) unused imports, grouped path list
     unused_imports: FxIndexMap<ast::NodeId, UnusedImport<'a>>,
     base_use_tree: Option<&'a ast::UseTree>,
     base_id: ast::NodeId,
     item_span: Span,
 }
 
-impl<'a, 'b> UnusedImportCheckVisitor<'a, 'b> {
+impl<'a, 'b, 'tcx> UnusedImportCheckVisitor<'a, 'b, 'tcx> {
     // We have information about whether `use` (import) items are actually
     // used now. If an import is not used at all, we signal a lint error.
     fn check_import(&mut self, id: ast::NodeId) {
@@ -94,7 +94,7 @@ impl<'a, 'b> UnusedImportCheckVisitor<'a, 'b> {
     }
 }
 
-impl<'a, 'b> Visitor<'a> for UnusedImportCheckVisitor<'a, 'b> {
+impl<'a, 'b, 'tcx> Visitor<'a> for UnusedImportCheckVisitor<'a, 'b, 'tcx> {
     fn visit_item(&mut self, item: &'a ast::Item) {
         self.item_span = item.span_with_attributes();
 
@@ -222,7 +222,7 @@ fn calc_unused_spans(
     }
 }
 
-impl Resolver<'_> {
+impl Resolver<'_, '_> {
     pub(crate) fn check_unused(&mut self, krate: &ast::Crate) {
         for import in self.potentially_unused_imports.iter() {
             match import.kind {

compiler/rustc_resolve/src/def_collector.rs

@@ -9,7 +9,7 @@ use rustc_span::symbol::sym;
 use rustc_span::Span;
 
 pub(crate) fn collect_definitions(
-    resolver: &mut Resolver<'_>,
+    resolver: &mut Resolver<'_, '_>,
     fragment: &AstFragment,
     expansion: LocalExpnId,
 ) {
@@ -18,14 +18,14 @@ pub(crate) fn collect_definitions(
 }
 
 /// Creates `DefId`s for nodes in the AST.
-struct DefCollector<'a, 'b> {
-    resolver: &'a mut Resolver<'b>,
+struct DefCollector<'a, 'b, 'tcx> {
+    resolver: &'a mut Resolver<'b, 'tcx>,
     parent_def: LocalDefId,
     impl_trait_context: ImplTraitContext,
     expansion: LocalExpnId,
 }
 
-impl<'a, 'b> DefCollector<'a, 'b> {
+impl<'a, 'b, 'tcx> DefCollector<'a, 'b, 'tcx> {
     fn create_def(&mut self, node_id: NodeId, data: DefPathData, span: Span) -> LocalDefId {
         let parent_def = self.parent_def;
         debug!("create_def(node_id={:?}, data={:?}, parent_def={:?})", node_id, data, parent_def);
@@ -81,7 +81,7 @@ impl<'a, 'b> DefCollector<'a, 'b> {
     }
 }
 
-impl<'a, 'b> visit::Visitor<'a> for DefCollector<'a, 'b> {
+impl<'a, 'b, 'tcx> visit::Visitor<'a> for DefCollector<'a, 'b, 'tcx> {
     fn visit_item(&mut self, i: &'a Item) {
         debug!("visit_item: {:?}", i);
 

compiler/rustc_resolve/src/diagnostics.rs

@@ -114,7 +114,7 @@ fn reduce_impl_span_to_impl_keyword(sm: &SourceMap, impl_span: Span) -> Span {
     sm.span_until_whitespace(impl_span)
 }
 
-impl<'a> Resolver<'a> {
+impl<'a, 'tcx> Resolver<'a, 'tcx> {
     pub(crate) fn report_errors(&mut self, krate: &Crate) {
         self.report_with_use_injections(krate);
 
@@ -1883,7 +1883,7 @@ impl<'a> Resolver<'a> {
     }
 }
 
-impl<'a, 'b> ImportResolver<'a, 'b> {
+impl<'a, 'b, 'tcx> ImportResolver<'a, 'b, 'tcx> {
     /// Adds suggestions for a path that cannot be resolved.
     pub(crate) fn make_path_suggestion(
         &mut self,