5 files changed, 19 insertions, 38 deletions

diff --git a/src/bootstrap/bin/rustc.rs b/src/bootstrap/bin/rustc.rs
index 2e9044a8150..23f81c2c876 100644
--- a/src/bootstrap/bin/rustc.rs
+++ b/src/bootstrap/bin/rustc.rs
@@ -127,6 +127,8 @@ fn main() {
 
     if env::var_os("RUSTC_DENY_WARNINGS").is_some() &&
        env::var_os("RUSTC_EXTERNAL_TOOL").is_none() {
+        // When extending this list, search for `NO-RUSTC-WRAPPER` and add the new lints
+        // there as well, some code doesn't go through this `rustc` wrapper.
         cmd.arg("-Dwarnings");
         cmd.arg("-Drust_2018_idioms");
         cmd.arg("-Dunused_lifetimes");
diff --git a/src/libcore/array.rs b/src/libcore/array.rs
index 6023bc21e74..517893a1967 100644
--- a/src/libcore/array.rs
+++ b/src/libcore/array.rs
@@ -217,7 +217,7 @@ where
 }
 
 #[stable(feature = "rust1", since = "1.0.0")]
-impl<'a, 'b, A, B, const N: usize> PartialEq<[B; N]> for [A; N]
+impl<A, B, const N: usize> PartialEq<[B; N]> for [A; N]
 where
     A: PartialEq<B>,
     [A; N]: LengthAtMost32,
@@ -234,7 +234,7 @@ where
 }
 
 #[stable(feature = "rust1", since = "1.0.0")]
-impl<'a, 'b, A, B, const N: usize> PartialEq<[B]> for [A; N]
+impl<A, B, const N: usize> PartialEq<[B]> for [A; N]
 where
     A: PartialEq<B>,
     [A; N]: LengthAtMost32,
diff --git a/src/librustc/ty/query/job.rs b/src/librustc/ty/query/job.rs
index c4e798f7461..a25560ff762 100644
--- a/src/librustc/ty/query/job.rs
+++ b/src/librustc/ty/query/job.rs
@@ -1,35 +1,25 @@
-#![allow(unused_imports)] // `cfg(parallel_compiler)`
-
-use std::mem;
-use std::process;
-use std::{fmt, ptr};
+use crate::ty::context::TyCtxt;
+use crate::ty::query::plumbing::CycleError;
+use crate::ty::query::Query;
+use crate::ty::tls;
 
-use rustc_data_structures::fx::FxHashSet;
-use rustc_data_structures::sync::{Lock, LockGuard, Lrc, Weak};
-use rustc_data_structures::OnDrop;
-use rustc_data_structures::jobserver;
+use rustc_data_structures::sync::Lrc;
 use syntax_pos::Span;
 
-use crate::ty::tls;
-use crate::ty::query::Query;
-use crate::ty::query::plumbing::CycleError;
 #[cfg(not(parallel_compiler))]
-use crate::ty::query::{
-    plumbing::TryGetJob,
-    config::QueryDescription,
-};
-use crate::ty::context::TyCtxt;
+use std::ptr;
 
 #[cfg(parallel_compiler)]
 use {
-    rustc_rayon_core as rayon_core,
     parking_lot::{Mutex, Condvar},
-    std::sync::atomic::Ordering,
-    std::thread,
-    std::iter,
-    std::iter::FromIterator,
+    rustc_data_structures::{jobserver, OnDrop},
+    rustc_data_structures::fx::FxHashSet,
+    rustc_data_structures::stable_hasher::{StableHasher, HashStable},
+    rustc_data_structures::sync::Lock,
+    rustc_rayon_core as rayon_core,
     syntax_pos::DUMMY_SP,
-    rustc_data_structures::stable_hasher::{StableHasherResult, StableHasher, HashStable},
+    std::{mem, process, thread},
+    std::iter::FromIterator,
 };
 
 /// Indicates the state of a query for a given key in a query map.
@@ -81,7 +71,7 @@ impl<'tcx> QueryJob<'tcx> {
         span: Span,
     ) -> Result<(), CycleError<'tcx>> {
         tls::with_related_context(tcx, move |icx| {
-            let mut waiter = Lrc::new(QueryWaiter {
+            let waiter = Lrc::new(QueryWaiter {
                 query: icx.query.clone(),
                 span,
                 cycle: Lock::new(None),
@@ -432,7 +422,7 @@ fn remove_cycle<'tcx>(
         let usage = usage.as_ref().map(|(span, query)| (*span, query.info.query.clone()));
 
         // Create the cycle error
-        let mut error = CycleError {
+        let error = CycleError {
             usage,
             cycle: stack.iter().map(|&(s, ref q)| QueryInfo {
                 span: s,
@@ -464,9 +454,6 @@ fn remove_cycle<'tcx>(
 /// Must only be called when a deadlock is about to happen.
 #[cfg(parallel_compiler)]
 pub unsafe fn handle_deadlock() {
-    use syntax;
-    use syntax_pos;
-
     let registry = rayon_core::Registry::current();
 
     let gcx_ptr = tls::GCX_PTR.with(|gcx_ptr| {
@@ -474,11 +461,6 @@ pub unsafe fn handle_deadlock() {
     });
     let gcx_ptr = &*gcx_ptr;
 
-    let syntax_globals = syntax::GLOBALS.with(|syntax_globals| {
-        syntax_globals as *const _
-    });
-    let syntax_globals = &*syntax_globals;
-
     let syntax_pos_globals = syntax_pos::GLOBALS.with(|syntax_pos_globals| {
         syntax_pos_globals as *const _
     });
diff --git a/src/librustc_interface/passes.rs b/src/librustc_interface/passes.rs
index ac36ad7e30b..8dd2595967f 100644
--- a/src/librustc_interface/passes.rs
+++ b/src/librustc_interface/passes.rs
@@ -17,7 +17,6 @@ use rustc::util::common::{time, ErrorReported};
 use rustc::session::Session;
 use rustc::session::config::{self, CrateType, Input, OutputFilenames, OutputType};
 use rustc::session::search_paths::PathKind;
-use rustc_allocator as allocator;
 use rustc_ast_borrowck as borrowck;
 use rustc_codegen_ssa::back::link::emit_metadata;
 use rustc_codegen_utils::codegen_backend::CodegenBackend;
diff --git a/src/librustc_interface/util.rs b/src/librustc_interface/util.rs
index 6ae5e94b11a..f007a0cf2ab 100644
--- a/src/librustc_interface/util.rs
+++ b/src/librustc_interface/util.rs
@@ -203,8 +203,6 @@ pub fn spawn_thread_pool<F: FnOnce() -> R + Send, R: Send>(
     f: F,
 ) -> R {
     use rayon::{ThreadPool, ThreadPoolBuilder};
-    use syntax;
-    use syntax_pos;
 
     let gcx_ptr = &Lock::new(0);