Avoid using feed_unit_query from within queries

rust-lang · workingjubilee · Jul 24, 2023 · Dec 11, 2023 · Dec 11, 2023 · Feb 14, 2024
commit ef00fae46d6bf05b1ea7c5447410f0cdf8dc2267
diff --git a/compiler/rustc_ast_lowering/src/lib.rs b/compiler/rustc_ast_lowering/src/lib.rs
@@ -427,7 +427,7 @@ pub fn lower_to_hir(tcx: TyCtxt<'_>, (): ()) -> hir::Crate<'_> {
     tcx.ensure_with_value().early_lint_checks(());
     tcx.ensure_with_value().debugger_visualizers(LOCAL_CRATE);
     tcx.ensure_with_value().get_lang_items(());
-    let (mut resolver, krate) = tcx.resolver_for_lowering(()).steal();
+    let (mut resolver, krate) = tcx.resolver_for_lowering().steal();
 
     let ast_index = index_crate(&resolver.node_id_to_def_id, &krate);
     let mut owners = IndexVec::from_fn_n(

diff --git a/compiler/rustc_driver_impl/src/lib.rs b/compiler/rustc_driver_impl/src/lib.rs
@@ -417,7 +417,7 @@ fn run_compiler(
             }
 
             // Make sure name resolution and macro expansion is run.
-            queries.global_ctxt()?.enter(|tcx| tcx.resolver_for_lowering(()));
+            queries.global_ctxt()?.enter(|tcx| tcx.resolver_for_lowering());
 
             if callbacks.after_expansion(compiler, queries) == Compilation::Stop {
                 return early_exit();

diff --git a/compiler/rustc_driver_impl/src/pretty.rs b/compiler/rustc_driver_impl/src/pretty.rs
@@ -229,7 +229,7 @@ impl<'tcx> PrintExtra<'tcx> {
     {
         match self {
             PrintExtra::AfterParsing { krate, .. } => f(krate),
-            PrintExtra::NeedsAstMap { tcx } => f(&tcx.resolver_for_lowering(()).borrow().1),
+            PrintExtra::NeedsAstMap { tcx } => f(&tcx.resolver_for_lowering().borrow().1),
         }
     }
 
@@ -281,7 +281,7 @@ pub fn print<'tcx>(sess: &Session, ppm: PpMode, ex: PrintExtra<'tcx>) {
         }
         AstTreeExpanded => {
             debug!("pretty-printing expanded AST");
-            format!("{:#?}", ex.tcx().resolver_for_lowering(()).borrow().1)
+            format!("{:#?}", ex.tcx().resolver_for_lowering().borrow().1)
         }
         Hir(s) => {
             debug!("pretty printing HIR {:?}", s);

diff --git a/compiler/rustc_interface/src/passes.rs b/compiler/rustc_interface/src/passes.rs
@@ -280,7 +280,7 @@ fn configure_and_expand(
 
 fn early_lint_checks(tcx: TyCtxt<'_>, (): ()) {
     let sess = tcx.sess;
-    let (resolver, krate) = &*tcx.resolver_for_lowering(()).borrow();
+    let (resolver, krate) = &*tcx.resolver_for_lowering().borrow();
     let mut lint_buffer = resolver.lint_buffer.steal();
 
     if sess.opts.unstable_opts.input_stats {
@@ -531,10 +531,10 @@ fn write_out_deps(tcx: TyCtxt<'_>, outputs: &OutputFilenames, out_filenames: &[P
     }
 }
 
-fn resolver_for_lowering<'tcx>(
+fn resolver_for_lowering_raw<'tcx>(
     tcx: TyCtxt<'tcx>,
     (): (),
-) -> &'tcx Steal<(ty::ResolverAstLowering, Lrc<ast::Crate>)> {
+) -> (&'tcx Steal<(ty::ResolverAstLowering, Lrc<ast::Crate>)>, &'tcx ty::ResolverGlobalCtxt) {
     let arenas = Resolver::arenas();
     let _ = tcx.registered_tools(()); // Uses `crate_for_resolver`.
     let (krate, pre_configured_attrs) = tcx.crate_for_resolver(()).steal();
@@ -549,16 +549,15 @@ fn resolver_for_lowering<'tcx>(
         ast_lowering: untracked_resolver_for_lowering,
     } = resolver.into_outputs();
 
-    let feed = tcx.feed_unit_query();
-    feed.resolutions(tcx.arena.alloc(untracked_resolutions));
-    tcx.arena.alloc(Steal::new((untracked_resolver_for_lowering, Lrc::new(krate))))
+    let resolutions = tcx.arena.alloc(untracked_resolutions);
+    (tcx.arena.alloc(Steal::new((untracked_resolver_for_lowering, Lrc::new(krate)))), resolutions)
 }
 
 pub(crate) fn write_dep_info(tcx: TyCtxt<'_>) {
     // Make sure name resolution and macro expansion is run for
     // the side-effect of providing a complete set of all
     // accessed files and env vars.
-    let _ = tcx.resolver_for_lowering(());
+    let _ = tcx.resolver_for_lowering();
 
     let sess = tcx.sess;
     let _timer = sess.timer("write_dep_info");
@@ -607,9 +606,10 @@ pub static DEFAULT_QUERY_PROVIDERS: LazyLock<Providers> = LazyLock::new(|| {
     let providers = &mut Providers::default();
     providers.analysis = analysis;
     providers.hir_crate = rustc_ast_lowering::lower_to_hir;
-    providers.resolver_for_lowering = resolver_for_lowering;
+    providers.resolver_for_lowering_raw = resolver_for_lowering_raw;
     providers.stripped_cfg_items =
         |tcx, _| tcx.arena.alloc_from_iter(tcx.resolutions(()).stripped_cfg_items.steal());
+    providers.resolutions = |tcx, ()| tcx.resolver_for_lowering_raw(()).1;
     providers.early_lint_checks = early_lint_checks;
     proc_macro_decls::provide(providers);
     rustc_const_eval::provide(providers);

diff --git a/compiler/rustc_middle/src/query/mod.rs b/compiler/rustc_middle/src/query/mod.rs
@@ -125,12 +125,11 @@ rustc_queries! {
     }
 
     query resolutions(_: ()) -> &'tcx ty::ResolverGlobalCtxt {
-        feedable
         no_hash
         desc { "getting the resolver outputs" }
     }
 
-    query resolver_for_lowering(_: ()) -> &'tcx Steal<(ty::ResolverAstLowering, Lrc<ast::Crate>)> {
+    query resolver_for_lowering_raw(_: ()) -> (&'tcx Steal<(ty::ResolverAstLowering, Lrc<ast::Crate>)>, &'tcx ty::ResolverGlobalCtxt) {
         eval_always
         no_hash
         desc { "getting the resolver for lowering" }

diff --git a/compiler/rustc_middle/src/ty/context.rs b/compiler/rustc_middle/src/ty/context.rs
@@ -39,7 +39,7 @@ use rustc_data_structures::profiling::SelfProfilerRef;
 use rustc_data_structures::sharded::{IntoPointer, ShardedHashMap};
 use rustc_data_structures::stable_hasher::{HashStable, StableHasher};
 use rustc_data_structures::steal::Steal;
-use rustc_data_structures::sync::{self, FreezeReadGuard, Lock, WorkerLocal};
+use rustc_data_structures::sync::{self, FreezeReadGuard, Lock, Lrc, WorkerLocal};
 #[cfg(parallel_compiler)]
 use rustc_data_structures::sync::{DynSend, DynSync};
 use rustc_data_structures::unord::UnordSet;
@@ -553,6 +553,7 @@ impl<'tcx> TyCtxt<'tcx> {
     /// Can only be fed before queries are run, and is thus exempt from any
     /// incremental issues. Do not use except for the initial query feeding.
     pub fn feed_unit_query(self) -> TyCtxtFeed<'tcx, ()> {
+        self.dep_graph.assert_ignored();
         TyCtxtFeed { tcx: self, key: () }
     }
 
@@ -2383,6 +2384,10 @@ impl<'tcx> TyCtxt<'tcx> {
         self.resolutions(()).module_children.get(&def_id).map_or(&[], |v| &v[..])
     }
 
+    pub fn resolver_for_lowering(self) -> &'tcx Steal<(ty::ResolverAstLowering, Lrc<ast::Crate>)> {
+        self.resolver_for_lowering_raw(()).0
+    }
+
     /// Given an `impl_id`, return the trait it implements.
     /// Return `None` if this is an inherent impl.
     pub fn impl_trait_ref(

diff --git a/compiler/rustc_passes/src/debugger_visualizer.rs b/compiler/rustc_passes/src/debugger_visualizer.rs
@@ -87,7 +87,7 @@ impl<'ast> rustc_ast::visit::Visitor<'ast> for DebuggerVisualizerCollector<'_> {
 
 /// Traverses and collects the debugger visualizers for a specific crate.
 fn debugger_visualizers(tcx: TyCtxt<'_>, _: LocalCrate) -> Vec<DebuggerVisualizerFile> {
-    let resolver_and_krate = tcx.resolver_for_lowering(()).borrow();
+    let resolver_and_krate = tcx.resolver_for_lowering().borrow();
     let krate = &*resolver_and_krate.1;
 
     let mut visitor = DebuggerVisualizerCollector { sess: tcx.sess, visualizers: Vec::new() };

diff --git a/compiler/rustc_passes/src/lang_items.rs b/compiler/rustc_passes/src/lang_items.rs
@@ -243,7 +243,7 @@ impl<'ast, 'tcx> LanguageItemCollector<'ast, 'tcx> {
 
 /// Traverses and collects all the lang items in all crates.
 fn get_lang_items(tcx: TyCtxt<'_>, (): ()) -> LanguageItems {
-    let resolver = tcx.resolver_for_lowering(()).borrow();
+    let resolver = tcx.resolver_for_lowering().borrow();
     let (resolver, krate) = &*resolver;
 
     // Initialize the collector.

diff --git a/tests/ui/panics/default-backtrace-ice.stderr b/tests/ui/panics/default-backtrace-ice.stderr
@@ -21,5 +21,5 @@ error: the compiler unexpectedly panicked. this is a bug.
 
 
 query stack during panic:
-#0 [resolver_for_lowering] getting the resolver for lowering
+#0 [resolver_for_lowering_raw] getting the resolver for lowering
 end of query stack