From 4b598d3f75c1802cae68c6967fe7ea2a83e437ae Mon Sep 17 00:00:00 2001
From: Camille GILLOT <gillot.camille@gmail.com>
Date: Sat, 31 Jul 2021 22:50:43 +0200
Subject: [PATCH] Stop emitting lints during lowering.

---
 compiler/rustc_ast_lowering/src/lib.rs |  3 ---
 compiler/rustc_interface/src/passes.rs | 32 ++++++++++++--------------
 compiler/rustc_resolve/src/lib.rs      |  4 ----
 3 files changed, 15 insertions(+), 24 deletions(-)

diff --git a/compiler/rustc_ast_lowering/src/lib.rs b/compiler/rustc_ast_lowering/src/lib.rs
index 833a21c1394..71999eeac4e 100644
--- a/compiler/rustc_ast_lowering/src/lib.rs
+++ b/compiler/rustc_ast_lowering/src/lib.rs
@@ -57,7 +57,6 @@ use rustc_hir::intravisit;
 use rustc_hir::{ConstArg, GenericArg, ItemLocalId, ParamName, TraitCandidate};
 use rustc_index::vec::{Idx, IndexVec};
 use rustc_query_system::ich::StableHashingContext;
-use rustc_session::lint::LintBuffer;
 use rustc_session::parse::feature_err;
 use rustc_session::utils::{FlattenNonterminals, NtToTokenstream};
 use rustc_session::Session;
@@ -180,8 +179,6 @@ pub trait ResolverAstLowering {
 
     fn definitions(&self) -> &Definitions;
 
-    fn lint_buffer(&mut self) -> &mut LintBuffer;
-
     fn next_node_id(&mut self) -> NodeId;
 
     fn take_trait_map(&mut self, node: NodeId) -> Option<Vec<hir::TraitCandidate>>;
diff --git a/compiler/rustc_interface/src/passes.rs b/compiler/rustc_interface/src/passes.rs
index ea4955e9a54..f2164bccc3e 100644
--- a/compiler/rustc_interface/src/passes.rs
+++ b/compiler/rustc_interface/src/passes.rs
@@ -487,12 +487,24 @@ pub fn configure_and_expand(
         }
     });
 
+    sess.time("early_lint_checks", || {
+        let lint_buffer = Some(std::mem::take(resolver.lint_buffer()));
+        rustc_lint::check_ast_node(
+            sess,
+            false,
+            lint_store,
+            resolver.registered_tools(),
+            lint_buffer,
+            rustc_lint::BuiltinCombinedEarlyLintPass::new(),
+            &krate,
+        )
+    });
+
     Ok(krate)
 }
 
 pub fn lower_to_hir<'res, 'tcx>(
     sess: &'tcx Session,
-    lint_store: &LintStore,
     resolver: &'res mut Resolver<'_>,
     krate: Rc<ast::Crate>,
     arena: &'tcx rustc_ast_lowering::Arena<'tcx>,
@@ -506,19 +518,6 @@ pub fn lower_to_hir<'res, 'tcx>(
         arena,
     );
 
-    sess.time("early_lint_checks", || {
-        let lint_buffer = Some(std::mem::take(resolver.lint_buffer()));
-        rustc_lint::check_ast_node(
-            sess,
-            false,
-            lint_store,
-            resolver.registered_tools(),
-            lint_buffer,
-            rustc_lint::BuiltinCombinedEarlyLintPass::new(),
-            &*krate,
-        )
-    });
-
     // Drop AST to free memory
     sess.time("drop_ast", || std::mem::drop(krate));
 
@@ -852,9 +851,8 @@ pub fn create_global_ctxt<'tcx>(
     dep_graph.assert_ignored();
 
     let sess = &compiler.session();
-    let krate = resolver
-        .borrow_mut()
-        .access(|resolver| lower_to_hir(sess, &lint_store, resolver, krate, hir_arena));
+    let krate =
+        resolver.borrow_mut().access(|resolver| lower_to_hir(sess, resolver, krate, hir_arena));
     let resolver_outputs = BoxedResolver::to_resolver_outputs(resolver);
 
     let query_result_on_disk_cache = rustc_incremental::load_query_result_cache(sess);
diff --git a/compiler/rustc_resolve/src/lib.rs b/compiler/rustc_resolve/src/lib.rs
index 3d31315d044..1f0a6e5ce97 100644
--- a/compiler/rustc_resolve/src/lib.rs
+++ b/compiler/rustc_resolve/src/lib.rs
@@ -1204,10 +1204,6 @@ impl ResolverAstLowering for Resolver<'_> {
         &self.definitions
     }
 
-    fn lint_buffer(&mut self) -> &mut LintBuffer {
-        &mut self.lint_buffer
-    }
-
     fn next_node_id(&mut self) -> NodeId {
         self.next_node_id()
     }