diff --git a/src/libproc_macro/bridge/scoped_cell.rs b/src/libproc_macro/bridge/scoped_cell.rs
index 6f7965095b638..89fb707001589 100644
--- a/src/libproc_macro/bridge/scoped_cell.rs
+++ b/src/libproc_macro/bridge/scoped_cell.rs
@@ -74,7 +74,7 @@ impl<T: LambdaL> ScopedCell<T> {
     }
 
     /// Sets the value in `self` to `value` while running `f`.
-    pub fn set<'a, R>(&self, value: <T as ApplyL<'a>>::Out, f: impl FnOnce() -> R) -> R {
+    pub fn set<R>(&self, value: <T as ApplyL<'_>>::Out, f: impl FnOnce() -> R) -> R {
         self.replace(value, |_| f())
     }
 }
diff --git a/src/librustc/cfg/construct.rs b/src/librustc/cfg/construct.rs
index 403e2f02f0545..a132575b0c673 100644
--- a/src/librustc/cfg/construct.rs
+++ b/src/librustc/cfg/construct.rs
@@ -30,7 +30,7 @@ struct LoopScope {
     break_index: CFGIndex,    // where to go on a `break`
 }
 
-pub fn construct<'tcx>(tcx: TyCtxt<'tcx>, body: &hir::Body) -> CFG {
+pub fn construct(tcx: TyCtxt<'_>, body: &hir::Body) -> CFG {
     let mut graph = graph::Graph::new();
     let entry = graph.add_node(CFGNodeData::Entry);
 
diff --git a/src/librustc/cfg/mod.rs b/src/librustc/cfg/mod.rs
index db168d99a0801..88fc7fbfad51f 100644
--- a/src/librustc/cfg/mod.rs
+++ b/src/librustc/cfg/mod.rs
@@ -49,7 +49,7 @@ pub type CFGNode = graph::Node<CFGNodeData>;
 pub type CFGEdge = graph::Edge<CFGEdgeData>;
 
 impl CFG {
-    pub fn new<'tcx>(tcx: TyCtxt<'tcx>, body: &hir::Body) -> CFG {
+    pub fn new(tcx: TyCtxt<'_>, body: &hir::Body) -> CFG {
         construct::construct(tcx, body)
     }
 
diff --git a/src/librustc/dep_graph/graph.rs b/src/librustc/dep_graph/graph.rs
index 93c22c3e713c0..b8c6c1e372382 100644
--- a/src/librustc/dep_graph/graph.rs
+++ b/src/librustc/dep_graph/graph.rs
@@ -841,7 +841,7 @@ impl DepGraph {
     //
     // This method will only load queries that will end up in the disk cache.
     // Other queries will not be executed.
-    pub fn exec_cache_promotions<'tcx>(&self, tcx: TyCtxt<'tcx>) {
+    pub fn exec_cache_promotions(&self, tcx: TyCtxt<'_>) {
         let data = self.data.as_ref().unwrap();
         for prev_index in data.colors.values.indices() {
             match data.colors.get(prev_index) {
diff --git a/src/librustc/hir/check_attr.rs b/src/librustc/hir/check_attr.rs
index 4b84d56858cca..9160b8024ee45 100644
--- a/src/librustc/hir/check_attr.rs
+++ b/src/librustc/hir/check_attr.rs
@@ -347,7 +347,7 @@ fn is_c_like_enum(item: &hir::Item) -> bool {
     }
 }
 
-fn check_mod_attrs<'tcx>(tcx: TyCtxt<'tcx>, module_def_id: DefId) {
+fn check_mod_attrs(tcx: TyCtxt<'_>, module_def_id: DefId) {
     tcx.hir().visit_item_likes_in_module(
         module_def_id,
         &mut CheckAttrVisitor { tcx }.as_deep_visitor()
diff --git a/src/librustc/hir/map/hir_id_validator.rs b/src/librustc/hir/map/hir_id_validator.rs
index 60465c04ec62f..891a1956bc971 100644
--- a/src/librustc/hir/map/hir_id_validator.rs
+++ b/src/librustc/hir/map/hir_id_validator.rs
@@ -4,7 +4,7 @@ use crate::hir::itemlikevisit::ItemLikeVisitor;
 use rustc_data_structures::fx::FxHashSet;
 use rustc_data_structures::sync::{Lock, ParallelIterator, par_iter};
 
-pub fn check_crate<'hir>(hir_map: &hir::map::Map<'hir>) {
+pub fn check_crate(hir_map: &hir::map::Map<'_>) {
     hir_map.dep_graph.assert_ignored();
 
     let errors = Lock::new(Vec::new());
diff --git a/src/librustc/hir/map/mod.rs b/src/librustc/hir/map/mod.rs
index 3d591c9a1c6bd..037d04a5d8ed3 100644
--- a/src/librustc/hir/map/mod.rs
+++ b/src/librustc/hir/map/mod.rs
@@ -147,7 +147,7 @@ impl Forest {
         }
     }
 
-    pub fn krate<'hir>(&'hir self) -> &'hir Crate {
+    pub fn krate(&self) -> &Crate {
         self.dep_graph.read(DepNode::new_no_params(DepKind::Krate));
         &self.krate
     }
@@ -155,7 +155,7 @@ impl Forest {
     /// This is used internally in the dependency tracking system.
     /// Use the `krate` method to ensure your dependency on the
     /// crate is tracked.
-    pub fn untracked_krate<'hir>(&'hir self) -> &'hir Crate {
+    pub fn untracked_krate(&self) -> &Crate {
         &self.krate
     }
 }
@@ -1085,7 +1085,7 @@ impl<'a> NodesMatchingSuffix<'a> {
         // If `id` itself is a mod named `m` with parent `p`, then
         // returns `Some(id, m, p)`.  If `id` has no mod in its parent
         // chain, then returns `None`.
-        fn find_first_mod_parent<'a>(map: &'a Map<'_>, mut id: HirId) -> Option<(HirId, Name)> {
+        fn find_first_mod_parent(map: &Map<'_>, mut id: HirId) -> Option<(HirId, Name)> {
             loop {
                 if let Node::Item(item) = map.find(id)? {
                     if item_is_mod(&item) {
diff --git a/src/librustc/infer/type_variable.rs b/src/librustc/infer/type_variable.rs
index dcafb0f3976ff..e30e86998a8c6 100644
--- a/src/librustc/infer/type_variable.rs
+++ b/src/librustc/infer/type_variable.rs
@@ -115,7 +115,7 @@ impl<'tcx> TypeVariableTable<'tcx> {
     ///
     /// Note that this function does not return care whether
     /// `vid` has been unified with something else or not.
-    pub fn var_diverges<'a>(&'a self, vid: ty::TyVid) -> bool {
+    pub fn var_diverges(&self, vid: ty::TyVid) -> bool {
         self.values.get(vid.index as usize).diverging
     }
 
diff --git a/src/librustc/lint/mod.rs b/src/librustc/lint/mod.rs
index 309af4b72c127..59b08b832d272 100644
--- a/src/librustc/lint/mod.rs
+++ b/src/librustc/lint/mod.rs
@@ -765,7 +765,7 @@ pub fn maybe_lint_level_root(tcx: TyCtxt<'_>, id: hir::HirId) -> bool {
     attrs.iter().any(|attr| Level::from_symbol(attr.name_or_empty()).is_some())
 }
 
-fn lint_levels<'tcx>(tcx: TyCtxt<'tcx>, cnum: CrateNum) -> &'tcx LintLevelMap {
+fn lint_levels(tcx: TyCtxt<'_>, cnum: CrateNum) -> &LintLevelMap {
     assert_eq!(cnum, LOCAL_CRATE);
     let mut builder = LintLevelMapBuilder {
         levels: LintLevelSets::builder(tcx.sess),
diff --git a/src/librustc/middle/cstore.rs b/src/librustc/middle/cstore.rs
index 2e9e1ac582f81..5a580dfa420b3 100644
--- a/src/librustc/middle/cstore.rs
+++ b/src/librustc/middle/cstore.rs
@@ -211,7 +211,7 @@ pub trait CrateStore {
     fn crates_untracked(&self) -> Vec<CrateNum>;
 
     // utility functions
-    fn encode_metadata<'tcx>(&self, tcx: TyCtxt<'tcx>) -> EncodedMetadata;
+    fn encode_metadata(&self, tcx: TyCtxt<'_>) -> EncodedMetadata;
     fn metadata_encoding_version(&self) -> &[u8];
 }
 
diff --git a/src/librustc/middle/dead.rs b/src/librustc/middle/dead.rs
index e02ee8943603a..e1889aa555f86 100644
--- a/src/librustc/middle/dead.rs
+++ b/src/librustc/middle/dead.rs
@@ -26,7 +26,7 @@ use syntax_pos;
 // explored. For example, if it's a live Node::Item that is a
 // function, then we should explore its block to check for codes that
 // may need to be marked as live.
-fn should_explore<'tcx>(tcx: TyCtxt<'tcx>, hir_id: hir::HirId) -> bool {
+fn should_explore(tcx: TyCtxt<'_>, hir_id: hir::HirId) -> bool {
     match tcx.hir().find(hir_id) {
         Some(Node::Item(..)) |
         Some(Node::ImplItem(..)) |
@@ -662,7 +662,7 @@ impl Visitor<'tcx> for DeadVisitor<'tcx> {
     }
 }
 
-pub fn check_crate<'tcx>(tcx: TyCtxt<'tcx>) {
+pub fn check_crate(tcx: TyCtxt<'_>) {
     let access_levels = &tcx.privacy_access_levels(LOCAL_CRATE);
     let krate = tcx.hir().krate();
     let live_symbols = find_live(tcx, access_levels, krate);
diff --git a/src/librustc/middle/dependency_format.rs b/src/librustc/middle/dependency_format.rs
index 879da6413e28a..96b99fe4cdce2 100644
--- a/src/librustc/middle/dependency_format.rs
+++ b/src/librustc/middle/dependency_format.rs
@@ -81,7 +81,7 @@ pub enum Linkage {
     Dynamic,
 }
 
-pub fn calculate<'tcx>(tcx: TyCtxt<'tcx>) {
+pub fn calculate(tcx: TyCtxt<'_>) {
     let sess = &tcx.sess;
     let fmts = sess.crate_types.borrow().iter().map(|&ty| {
         let linkage = calculate_type(tcx, ty);
@@ -92,7 +92,7 @@ pub fn calculate<'tcx>(tcx: TyCtxt<'tcx>) {
     sess.dependency_formats.set(fmts);
 }
 
-fn calculate_type<'tcx>(tcx: TyCtxt<'tcx>, ty: config::CrateType) -> DependencyList {
+fn calculate_type(tcx: TyCtxt<'_>, ty: config::CrateType) -> DependencyList {
     let sess = &tcx.sess;
 
     if !sess.opts.output_types.should_codegen() {
@@ -267,7 +267,7 @@ fn add_library(
     }
 }
 
-fn attempt_static<'tcx>(tcx: TyCtxt<'tcx>) -> Option<DependencyList> {
+fn attempt_static(tcx: TyCtxt<'_>) -> Option<DependencyList> {
     let sess = &tcx.sess;
     let crates = cstore::used_crates(tcx, RequireStatic);
     if !crates.iter().by_ref().all(|&(_, ref p)| p.is_some()) {
@@ -324,7 +324,7 @@ fn activate_injected_dep(injected: Option<CrateNum>,
 
 // After the linkage for a crate has been determined we need to verify that
 // there's only going to be one allocator in the output.
-fn verify_ok<'tcx>(tcx: TyCtxt<'tcx>, list: &[Linkage]) {
+fn verify_ok(tcx: TyCtxt<'_>, list: &[Linkage]) {
     let sess = &tcx.sess;
     if list.len() == 0 {
         return
diff --git a/src/librustc/middle/intrinsicck.rs b/src/librustc/middle/intrinsicck.rs
index e8d68e0b7a7aa..1cc96c549e724 100644
--- a/src/librustc/middle/intrinsicck.rs
+++ b/src/librustc/middle/intrinsicck.rs
@@ -10,7 +10,7 @@ use syntax_pos::{Span, sym};
 use crate::hir::intravisit::{self, Visitor, NestedVisitorMap};
 use crate::hir;
 
-fn check_mod_intrinsics<'tcx>(tcx: TyCtxt<'tcx>, module_def_id: DefId) {
+fn check_mod_intrinsics(tcx: TyCtxt<'_>, module_def_id: DefId) {
     tcx.hir().visit_item_likes_in_module(
         module_def_id,
         &mut ItemVisitor { tcx }.as_deep_visitor()
diff --git a/src/librustc/middle/lib_features.rs b/src/librustc/middle/lib_features.rs
index 9c131ce63428b..694b0a9862960 100644
--- a/src/librustc/middle/lib_features.rs
+++ b/src/librustc/middle/lib_features.rs
@@ -142,7 +142,7 @@ impl Visitor<'tcx> for LibFeatureCollector<'tcx> {
     }
 }
 
-pub fn collect<'tcx>(tcx: TyCtxt<'tcx>) -> LibFeatures {
+pub fn collect(tcx: TyCtxt<'_>) -> LibFeatures {
     let mut collector = LibFeatureCollector::new(tcx);
     intravisit::walk_crate(&mut collector, tcx.hir().krate());
     collector.lib_features
diff --git a/src/librustc/middle/liveness.rs b/src/librustc/middle/liveness.rs
index 464bc4fd6dfd7..30ff835bdcc43 100644
--- a/src/librustc/middle/liveness.rs
+++ b/src/librustc/middle/liveness.rs
@@ -181,7 +181,7 @@ impl<'tcx> Visitor<'tcx> for IrMaps<'tcx> {
     fn visit_arm(&mut self, a: &'tcx hir::Arm) { visit_arm(self, a); }
 }
 
-fn check_mod_liveness<'tcx>(tcx: TyCtxt<'tcx>, module_def_id: DefId) {
+fn check_mod_liveness(tcx: TyCtxt<'_>, module_def_id: DefId) {
     tcx.hir().visit_item_likes_in_module(
         module_def_id,
         &mut IrMaps::new(tcx, module_def_id).as_deep_visitor(),
diff --git a/src/librustc/middle/reachable.rs b/src/librustc/middle/reachable.rs
index d607c35f8762b..6b26be34d7520 100644
--- a/src/librustc/middle/reachable.rs
+++ b/src/librustc/middle/reachable.rs
@@ -42,8 +42,8 @@ fn item_might_be_inlined(tcx: TyCtxt<'tcx>, item: &hir::Item, attrs: CodegenFnAt
     }
 }
 
-fn method_might_be_inlined<'tcx>(
-    tcx: TyCtxt<'tcx>,
+fn method_might_be_inlined(
+    tcx: TyCtxt<'_>,
     impl_item: &hir::ImplItem,
     impl_src: DefId,
 ) -> bool {
@@ -391,7 +391,7 @@ impl<'a, 'tcx> ItemLikeVisitor<'tcx> for CollectPrivateImplItemsVisitor<'a, 'tcx
 #[derive(Clone, HashStable)]
 pub struct ReachableSet(pub Lrc<HirIdSet>);
 
-fn reachable_set<'tcx>(tcx: TyCtxt<'tcx>, crate_num: CrateNum) -> ReachableSet {
+fn reachable_set(tcx: TyCtxt<'_>, crate_num: CrateNum) -> ReachableSet {
     debug_assert!(crate_num == LOCAL_CRATE);
 
     let access_levels = &tcx.privacy_access_levels(LOCAL_CRATE);
diff --git a/src/librustc/middle/region.rs b/src/librustc/middle/region.rs
index 114684b152402..67a4c2981a705 100644
--- a/src/librustc/middle/region.rs
+++ b/src/librustc/middle/region.rs
@@ -1446,7 +1446,7 @@ impl<'tcx> Visitor<'tcx> for RegionResolutionVisitor<'tcx> {
     }
 }
 
-fn region_scope_tree<'tcx>(tcx: TyCtxt<'tcx>, def_id: DefId) -> &'tcx ScopeTree {
+fn region_scope_tree(tcx: TyCtxt<'_>, def_id: DefId) -> &ScopeTree {
     let closure_base_def_id = tcx.closure_base_def_id(def_id);
     if closure_base_def_id != def_id {
         return tcx.region_scope_tree(closure_base_def_id);
diff --git a/src/librustc/middle/resolve_lifetime.rs b/src/librustc/middle/resolve_lifetime.rs
index c94893d8b7575..7776f38f53820 100644
--- a/src/librustc/middle/resolve_lifetime.rs
+++ b/src/librustc/middle/resolve_lifetime.rs
@@ -368,7 +368,7 @@ pub fn provide(providers: &mut ty::query::Providers<'_>) {
 /// entire crate. You should not read the result of this query
 /// directly, but rather use `named_region_map`, `is_late_bound_map`,
 /// etc.
-fn resolve_lifetimes<'tcx>(tcx: TyCtxt<'tcx>, for_krate: CrateNum) -> &'tcx ResolveLifetimes {
+fn resolve_lifetimes(tcx: TyCtxt<'_>, for_krate: CrateNum) -> &ResolveLifetimes {
     assert_eq!(for_krate, LOCAL_CRATE);
 
     let named_region_map = krate(tcx);
@@ -395,7 +395,7 @@ fn resolve_lifetimes<'tcx>(tcx: TyCtxt<'tcx>, for_krate: CrateNum) -> &'tcx Reso
     tcx.arena.alloc(rl)
 }
 
-fn krate<'tcx>(tcx: TyCtxt<'tcx>) -> NamedRegionMap {
+fn krate(tcx: TyCtxt<'_>) -> NamedRegionMap {
     let krate = tcx.hir().krate();
     let mut map = NamedRegionMap {
         defs: Default::default(),
diff --git a/src/librustc/middle/stability.rs b/src/librustc/middle/stability.rs
index 38df4060652b7..101563d2d99ef 100644
--- a/src/librustc/middle/stability.rs
+++ b/src/librustc/middle/stability.rs
@@ -466,7 +466,7 @@ impl<'tcx> Index<'tcx> {
 
 /// Cross-references the feature names of unstable APIs with enabled
 /// features and possibly prints errors.
-fn check_mod_unstable_api_usage<'tcx>(tcx: TyCtxt<'tcx>, module_def_id: DefId) {
+fn check_mod_unstable_api_usage(tcx: TyCtxt<'_>, module_def_id: DefId) {
     tcx.hir().visit_item_likes_in_module(module_def_id, &mut Checker { tcx }.as_deep_visitor());
 }
 
@@ -836,7 +836,7 @@ impl<'tcx> TyCtxt<'tcx> {
 /// Given the list of enabled features that were not language features (i.e., that
 /// were expected to be library features), and the list of features used from
 /// libraries, identify activated features that don't exist and error about them.
-pub fn check_unused_or_stable_features<'tcx>(tcx: TyCtxt<'tcx>) {
+pub fn check_unused_or_stable_features(tcx: TyCtxt<'_>) {
     let access_levels = &tcx.privacy_access_levels(LOCAL_CRATE);
 
     if tcx.stability().staged_api[&LOCAL_CRATE] {
@@ -920,8 +920,8 @@ pub fn check_unused_or_stable_features<'tcx>(tcx: TyCtxt<'tcx>) {
     // don't lint about unused features. We should reenable this one day!
 }
 
-fn unnecessary_stable_feature_lint<'tcx>(
-    tcx: TyCtxt<'tcx>,
+fn unnecessary_stable_feature_lint(
+    tcx: TyCtxt<'_>,
     span: Span,
     feature: Symbol,
     since: Symbol,
diff --git a/src/librustc/mir/mod.rs b/src/librustc/mir/mod.rs
index 9b1808c585ce7..59a032d53cfd6 100644
--- a/src/librustc/mir/mod.rs
+++ b/src/librustc/mir/mod.rs
@@ -2867,19 +2867,19 @@ impl<'tcx> graph::WithStartNode for Body<'tcx> {
 }
 
 impl<'tcx> graph::WithPredecessors for Body<'tcx> {
-    fn predecessors<'graph>(
-        &'graph self,
+    fn predecessors(
+        &self,
         node: Self::Node,
-    ) -> <Self as GraphPredecessors<'graph>>::Iter {
+    ) -> <Self as GraphPredecessors<'_>>::Iter {
         self.predecessors_for(node).clone().into_iter()
     }
 }
 
 impl<'tcx> graph::WithSuccessors for Body<'tcx> {
-    fn successors<'graph>(
-        &'graph self,
+    fn successors(
+        &self,
         node: Self::Node,
-    ) -> <Self as GraphSuccessors<'graph>>::Iter {
+    ) -> <Self as GraphSuccessors<'_>>::Iter {
         self.basic_blocks[node].terminator().successors().cloned()
     }
 }
diff --git a/src/librustc/session/config.rs b/src/librustc/session/config.rs
index 895f9c6d8fb85..d79215db94e97 100644
--- a/src/librustc/session/config.rs
+++ b/src/librustc/session/config.rs
@@ -269,11 +269,11 @@ impl OutputTypes {
         self.0.contains_key(key)
     }
 
-    pub fn keys<'a>(&'a self) -> BTreeMapKeysIter<'a, OutputType, Option<PathBuf>> {
+    pub fn keys(&self) -> BTreeMapKeysIter<'_, OutputType, Option<PathBuf>> {
         self.0.keys()
     }
 
-    pub fn values<'a>(&'a self) -> BTreeMapValuesIter<'a, OutputType, Option<PathBuf>> {
+    pub fn values(&self) -> BTreeMapValuesIter<'_, OutputType, Option<PathBuf>> {
         self.0.values()
     }
 
@@ -316,7 +316,7 @@ impl Externs {
         self.0.get(key)
     }
 
-    pub fn iter<'a>(&'a self) -> BTreeMapIter<'a, String, ExternEntry> {
+    pub fn iter(&self) -> BTreeMapIter<'_, String, ExternEntry> {
         self.0.iter()
     }
 }
diff --git a/src/librustc/session/mod.rs b/src/librustc/session/mod.rs
index bb4ef2d7bd426..6b54035942a78 100644
--- a/src/librustc/session/mod.rs
+++ b/src/librustc/session/mod.rs
@@ -215,66 +215,66 @@ impl Session {
         *self.crate_disambiguator.get()
     }
 
-    pub fn struct_span_warn<'a, S: Into<MultiSpan>>(
-        &'a self,
+    pub fn struct_span_warn<S: Into<MultiSpan>>(
+        &self,
         sp: S,
         msg: &str,
-    ) -> DiagnosticBuilder<'a> {
+    ) -> DiagnosticBuilder<'_> {
         self.diagnostic().struct_span_warn(sp, msg)
     }
-    pub fn struct_span_warn_with_code<'a, S: Into<MultiSpan>>(
-        &'a self,
+    pub fn struct_span_warn_with_code<S: Into<MultiSpan>>(
+        &self,
         sp: S,
         msg: &str,
         code: DiagnosticId,
-    ) -> DiagnosticBuilder<'a> {
+    ) -> DiagnosticBuilder<'_> {
         self.diagnostic().struct_span_warn_with_code(sp, msg, code)
     }
-    pub fn struct_warn<'a>(&'a self, msg: &str) -> DiagnosticBuilder<'a> {
+    pub fn struct_warn(&self, msg: &str) -> DiagnosticBuilder<'_> {
         self.diagnostic().struct_warn(msg)
     }
-    pub fn struct_span_err<'a, S: Into<MultiSpan>>(
-        &'a self,
+    pub fn struct_span_err<S: Into<MultiSpan>>(
+        &self,
         sp: S,
         msg: &str,
-    ) -> DiagnosticBuilder<'a> {
+    ) -> DiagnosticBuilder<'_> {
         self.diagnostic().struct_span_err(sp, msg)
     }
-    pub fn struct_span_err_with_code<'a, S: Into<MultiSpan>>(
-        &'a self,
+    pub fn struct_span_err_with_code<S: Into<MultiSpan>>(
+        &self,
         sp: S,
         msg: &str,
         code: DiagnosticId,
-    ) -> DiagnosticBuilder<'a> {
+    ) -> DiagnosticBuilder<'_> {
         self.diagnostic().struct_span_err_with_code(sp, msg, code)
     }
     // FIXME: This method should be removed (every error should have an associated error code).
-    pub fn struct_err<'a>(&'a self, msg: &str) -> DiagnosticBuilder<'a> {
+    pub fn struct_err(&self, msg: &str) -> DiagnosticBuilder<'_> {
         self.diagnostic().struct_err(msg)
     }
-    pub fn struct_err_with_code<'a>(
-        &'a self,
+    pub fn struct_err_with_code(
+        &self,
         msg: &str,
         code: DiagnosticId,
-    ) -> DiagnosticBuilder<'a> {
+    ) -> DiagnosticBuilder<'_> {
         self.diagnostic().struct_err_with_code(msg, code)
     }
-    pub fn struct_span_fatal<'a, S: Into<MultiSpan>>(
-        &'a self,
+    pub fn struct_span_fatal<S: Into<MultiSpan>>(
+        &self,
         sp: S,
         msg: &str,
-    ) -> DiagnosticBuilder<'a> {
+    ) -> DiagnosticBuilder<'_> {
         self.diagnostic().struct_span_fatal(sp, msg)
     }
-    pub fn struct_span_fatal_with_code<'a, S: Into<MultiSpan>>(
-        &'a self,
+    pub fn struct_span_fatal_with_code<S: Into<MultiSpan>>(
+        &self,
         sp: S,
         msg: &str,
         code: DiagnosticId,
-    ) -> DiagnosticBuilder<'a> {
+    ) -> DiagnosticBuilder<'_> {
         self.diagnostic().struct_span_fatal_with_code(sp, msg, code)
     }
-    pub fn struct_fatal<'a>(&'a self, msg: &str) -> DiagnosticBuilder<'a> {
+    pub fn struct_fatal(&self, msg: &str) -> DiagnosticBuilder<'_> {
         self.diagnostic().struct_fatal(msg)
     }
 
@@ -416,7 +416,7 @@ impl Session {
     pub fn next_node_id(&self) -> NodeId {
         self.reserve_node_ids(1)
     }
-    pub fn diagnostic<'a>(&'a self) -> &'a errors::Handler {
+    pub fn diagnostic(&self) -> &errors::Handler {
         &self.parse_sess.span_diagnostic
     }
 
@@ -504,7 +504,7 @@ impl Session {
         );
     }
 
-    pub fn source_map<'a>(&'a self) -> &'a source_map::SourceMap {
+    pub fn source_map(&self) -> &source_map::SourceMap {
         self.parse_sess.source_map()
     }
     pub fn verbose(&self) -> bool {
diff --git a/src/librustc/traits/coherence.rs b/src/librustc/traits/coherence.rs
index d8087af60acdf..b6f0addd77107 100644
--- a/src/librustc/traits/coherence.rs
+++ b/src/librustc/traits/coherence.rs
@@ -48,8 +48,8 @@ pub fn add_placeholder_note(err: &mut errors::DiagnosticBuilder<'_>) {
 /// If there are types that satisfy both impls, invokes `on_overlap`
 /// with a suitably-freshened `ImplHeader` with those types
 /// substituted. Otherwise, invokes `no_overlap`.
-pub fn overlapping_impls<'tcx, F1, F2, R>(
-    tcx: TyCtxt<'tcx>,
+pub fn overlapping_impls<F1, F2, R>(
+    tcx: TyCtxt<'_>,
     impl1_def_id: DefId,
     impl2_def_id: DefId,
     intercrate_mode: IntercrateMode,
@@ -247,10 +247,10 @@ pub enum OrphanCheckErr<'tcx> {
 ///
 /// 1. All type parameters in `Self` must be "covered" by some local type constructor.
 /// 2. Some local type must appear in `Self`.
-pub fn orphan_check<'tcx>(
-    tcx: TyCtxt<'tcx>,
+pub fn orphan_check(
+    tcx: TyCtxt<'_>,
     impl_def_id: DefId,
-) -> Result<(), OrphanCheckErr<'tcx>> {
+) -> Result<(), OrphanCheckErr<'_>> {
     debug!("orphan_check({:?})", impl_def_id);
 
     // We only except this routine to be invoked on implementations
diff --git a/src/librustc/traits/error_reporting.rs b/src/librustc/traits/error_reporting.rs
index f54575ff8fc1d..d6cc68bcdab46 100644
--- a/src/librustc/traits/error_reporting.rs
+++ b/src/librustc/traits/error_reporting.rs
@@ -247,7 +247,7 @@ impl<'a, 'tcx> InferCtxt<'a, 'tcx> {
     fn fuzzy_match_tys(&self, a: Ty<'tcx>, b: Ty<'tcx>) -> bool {
         /// returns the fuzzy category of a given type, or None
         /// if the type can be equated to any type.
-        fn type_category<'tcx>(t: Ty<'tcx>) -> Option<u32> {
+        fn type_category(t: Ty<'_>) -> Option<u32> {
             match t.sty {
                 ty::Bool => Some(0),
                 ty::Char => Some(1),
diff --git a/src/librustc/traits/object_safety.rs b/src/librustc/traits/object_safety.rs
index cfd5cfa897daf..37eff852abd01 100644
--- a/src/librustc/traits/object_safety.rs
+++ b/src/librustc/traits/object_safety.rs
@@ -702,6 +702,6 @@ impl<'tcx> TyCtxt<'tcx> {
     }
 }
 
-pub(super) fn is_object_safe_provider<'tcx>(tcx: TyCtxt<'tcx>, trait_def_id: DefId) -> bool {
+pub(super) fn is_object_safe_provider(tcx: TyCtxt<'_>, trait_def_id: DefId) -> bool {
     tcx.object_safety_violations(trait_def_id).is_empty()
 }
diff --git a/src/librustc/traits/project.rs b/src/librustc/traits/project.rs
index 8bd8f941fb3dd..20acf44340690 100644
--- a/src/librustc/traits/project.rs
+++ b/src/librustc/traits/project.rs
@@ -1509,8 +1509,8 @@ fn confirm_impl_candidate<'cx, 'tcx>(
 ///
 /// Based on the "projection mode", this lookup may in fact only examine the
 /// topmost impl. See the comments for `Reveal` for more details.
-fn assoc_ty_def<'cx, 'tcx>(
-    selcx: &SelectionContext<'cx, 'tcx>,
+fn assoc_ty_def(
+    selcx: &SelectionContext<'_, '_>,
     impl_def_id: DefId,
     assoc_ty_def_id: DefId,
 ) -> specialization_graph::NodeItem<ty::AssocItem> {
diff --git a/src/librustc/traits/specialize/mod.rs b/src/librustc/traits/specialize/mod.rs
index 43bb4edd9b27d..f0389bb037ac5 100644
--- a/src/librustc/traits/specialize/mod.rs
+++ b/src/librustc/traits/specialize/mod.rs
@@ -145,8 +145,8 @@ pub fn find_associated_item<'tcx>(
 /// Specialization is determined by the sets of types to which the impls apply;
 /// `impl1` specializes `impl2` if it applies to a subset of the types `impl2` applies
 /// to.
-pub(super) fn specializes<'tcx>(
-    tcx: TyCtxt<'tcx>,
+pub(super) fn specializes(
+    tcx: TyCtxt<'_>,
     (impl1_def_id, impl2_def_id): (DefId, DefId),
 ) -> bool {
     debug!("specializes({:?}, {:?})", impl1_def_id, impl2_def_id);
@@ -282,10 +282,10 @@ fn fulfill_implication<'a, 'tcx>(
 }
 
 // Query provider for `specialization_graph_of`.
-pub(super) fn specialization_graph_provider<'tcx>(
-    tcx: TyCtxt<'tcx>,
+pub(super) fn specialization_graph_provider(
+    tcx: TyCtxt<'_>,
     trait_id: DefId,
-) -> &'tcx specialization_graph::Graph {
+) -> &specialization_graph::Graph {
     let mut sg = specialization_graph::Graph::new();
 
     let mut trait_impls = tcx.all_impls(trait_id);
diff --git a/src/librustc/traits/util.rs b/src/librustc/traits/util.rs
index 2d295679be324..07d6f633143a2 100644
--- a/src/librustc/traits/util.rs
+++ b/src/librustc/traits/util.rs
@@ -417,7 +417,7 @@ pub struct SupertraitDefIds<'tcx> {
     visited: FxHashSet<DefId>,
 }
 
-pub fn supertrait_def_ids<'tcx>(tcx: TyCtxt<'tcx>, trait_def_id: DefId) -> SupertraitDefIds<'tcx> {
+pub fn supertrait_def_ids(tcx: TyCtxt<'_>, trait_def_id: DefId) -> SupertraitDefIds<'_> {
     SupertraitDefIds {
         tcx,
         stack: vec![trait_def_id],
diff --git a/src/librustc/ty/query/on_disk_cache.rs b/src/librustc/ty/query/on_disk_cache.rs
index 8b2183c42efd4..85153f99b1917 100644
--- a/src/librustc/ty/query/on_disk_cache.rs
+++ b/src/librustc/ty/query/on_disk_cache.rs
@@ -306,9 +306,9 @@ impl<'sess> OnDiskCache<'sess> {
     }
 
     /// Loads a diagnostic emitted during the previous compilation session.
-    pub fn load_diagnostics<'tcx>(
+    pub fn load_diagnostics(
         &self,
-        tcx: TyCtxt<'tcx>,
+        tcx: TyCtxt<'_>,
         dep_node_index: SerializedDepNodeIndex,
     ) -> Vec<Diagnostic> {
         let diagnostics: Option<EncodedDiagnostics> = self.load_indexed(
@@ -335,9 +335,9 @@ impl<'sess> OnDiskCache<'sess> {
 
     /// Returns the cached query result if there is something in the cache for
     /// the given `SerializedDepNodeIndex`; otherwise returns `None`.
-    pub fn try_load_query_result<'tcx, T>(
+    pub fn try_load_query_result<T>(
         &self,
-        tcx: TyCtxt<'tcx>,
+        tcx: TyCtxt<'_>,
         dep_node_index: SerializedDepNodeIndex,
     ) -> Option<T>
     where
diff --git a/src/librustc/ty/query/plumbing.rs b/src/librustc/ty/query/plumbing.rs
index 5a7d106700af2..0c9e31e1ff28e 100644
--- a/src/librustc/ty/query/plumbing.rs
+++ b/src/librustc/ty/query/plumbing.rs
@@ -1166,7 +1166,7 @@ macro_rules! define_provider_struct {
 /// then `force_from_dep_node()` should not fail for it. Otherwise, you can just
 /// add it to the "We don't have enough information to reconstruct..." group in
 /// the match below.
-pub fn force_from_dep_node<'tcx>(tcx: TyCtxt<'tcx>, dep_node: &DepNode) -> bool {
+pub fn force_from_dep_node(tcx: TyCtxt<'_>, dep_node: &DepNode) -> bool {
     use crate::dep_graph::RecoverKey;
 
     // We must avoid ever having to call force_from_dep_node() for a
diff --git a/src/librustc_borrowck/borrowck/check_loans.rs b/src/librustc_borrowck/borrowck/check_loans.rs
index 714b7c27200e3..a098cd1761236 100644
--- a/src/librustc_borrowck/borrowck/check_loans.rs
+++ b/src/librustc_borrowck/borrowck/check_loans.rs
@@ -354,7 +354,7 @@ impl<'a, 'tcx> CheckLoanCtxt<'a, 'tcx> {
                                          cmt: &mc::cmt_<'tcx>,
                                          loan_region: ty::Region<'tcx>,
                                          borrow_span: Span) {
-        pub fn borrow_of_local_data<'tcx>(cmt: &mc::cmt_<'tcx>) -> bool {
+        pub fn borrow_of_local_data(cmt: &mc::cmt_<'_>) -> bool {
             match cmt.cat {
                 // Borrows of static items is allowed
                 Categorization::StaticItem => false,
diff --git a/src/librustc_borrowck/borrowck/mod.rs b/src/librustc_borrowck/borrowck/mod.rs
index 3c7f19f7fbf4f..8763a6bc066b3 100644
--- a/src/librustc_borrowck/borrowck/mod.rs
+++ b/src/librustc_borrowck/borrowck/mod.rs
@@ -53,7 +53,7 @@ pub struct LoanDataFlowOperator;
 
 pub type LoanDataFlow<'tcx> = DataFlowContext<'tcx, LoanDataFlowOperator>;
 
-pub fn check_crate<'tcx>(tcx: TyCtxt<'tcx>) {
+pub fn check_crate(tcx: TyCtxt<'_>) {
     tcx.par_body_owners(|body_owner_def_id| {
         tcx.ensure().borrowck(body_owner_def_id);
     });
@@ -73,7 +73,7 @@ pub struct AnalysisData<'tcx> {
     pub move_data: move_data::FlowedMoveData<'tcx>,
 }
 
-fn borrowck<'tcx>(tcx: TyCtxt<'tcx>, owner_def_id: DefId) -> &'tcx BorrowCheckResult {
+fn borrowck(tcx: TyCtxt<'_>, owner_def_id: DefId) -> &BorrowCheckResult {
     assert!(tcx.use_ast_borrowck() || tcx.migrate_borrowck());
 
     debug!("borrowck(body_owner_def_id={:?})", owner_def_id);
diff --git a/src/librustc_borrowck/dataflow.rs b/src/librustc_borrowck/dataflow.rs
index f5d311b35d738..dc7014d22ec4d 100644
--- a/src/librustc_borrowck/dataflow.rs
+++ b/src/librustc_borrowck/dataflow.rs
@@ -84,9 +84,9 @@ struct PropagationContext<'a, 'tcx, O> {
     changed: bool,
 }
 
-fn get_cfg_indices<'a>(id: hir::ItemLocalId,
-                       index: &'a FxHashMap<hir::ItemLocalId, Vec<CFGIndex>>)
-                       -> &'a [CFGIndex] {
+fn get_cfg_indices(id: hir::ItemLocalId,
+                   index: &FxHashMap<hir::ItemLocalId, Vec<CFGIndex>>)
+                   -> &[CFGIndex] {
     index.get(&id).map_or(&[], |v| &v[..])
 }
 
diff --git a/src/librustc_codegen_llvm/back/write.rs b/src/librustc_codegen_llvm/back/write.rs
index 3638730707f3f..b135605cf02d7 100644
--- a/src/librustc_codegen_llvm/back/write.rs
+++ b/src/librustc_codegen_llvm/back/write.rs
@@ -239,9 +239,9 @@ impl<'a> Drop for DiagnosticHandlers<'a> {
     }
 }
 
-unsafe extern "C" fn report_inline_asm<'a, 'b>(cgcx: &'a CodegenContext<LlvmCodegenBackend>,
-                                               msg: &'b str,
-                                               cookie: c_uint) {
+unsafe extern "C" fn report_inline_asm(cgcx: &CodegenContext<LlvmCodegenBackend>,
+                                       msg: &str,
+                                       cookie: c_uint) {
     cgcx.diag_emitter.inline_asm_error(cookie as u32, msg.to_owned());
 }
 
diff --git a/src/librustc_codegen_llvm/base.rs b/src/librustc_codegen_llvm/base.rs
index 04645dacfec58..21c19e167cfbe 100644
--- a/src/librustc_codegen_llvm/base.rs
+++ b/src/librustc_codegen_llvm/base.rs
@@ -123,8 +123,8 @@ pub fn compile_codegen_unit(tcx: TyCtxt<'tcx>, cgu_name: InternedString) {
 
     submit_codegened_module_to_llvm(&LlvmCodegenBackend(()), tcx, module, cost);
 
-    fn module_codegen<'tcx>(
-        tcx: TyCtxt<'tcx>,
+    fn module_codegen(
+        tcx: TyCtxt<'_>,
         cgu_name: InternedString,
     ) -> ModuleCodegen<ModuleLlvm> {
         let cgu = tcx.codegen_unit(cgu_name);
diff --git a/src/librustc_codegen_llvm/builder.rs b/src/librustc_codegen_llvm/builder.rs
index 0709368ad860e..f67c740b77748 100644
--- a/src/librustc_codegen_llvm/builder.rs
+++ b/src/librustc_codegen_llvm/builder.rs
@@ -144,7 +144,7 @@ impl BuilderMethods<'a, 'tcx> for Builder<'a, 'll, 'tcx> {
         }
     }
 
-    fn build_sibling_block<'b>(&self, name: &'b str) -> Self {
+    fn build_sibling_block(&self, name: &str) -> Self {
         Builder::new_block(self.cx, self.llfn(), name)
     }
 
diff --git a/src/librustc_codegen_llvm/lib.rs b/src/librustc_codegen_llvm/lib.rs
index 7283aa95b3027..e6630e1816570 100644
--- a/src/librustc_codegen_llvm/lib.rs
+++ b/src/librustc_codegen_llvm/lib.rs
@@ -124,7 +124,7 @@ impl ExtraBackendMethods for LlvmCodegenBackend {
     ) {
         unsafe { allocator::codegen(tcx, mods, kind) }
     }
-    fn compile_codegen_unit<'tcx>(&self, tcx: TyCtxt<'tcx>, cgu_name: InternedString) {
+    fn compile_codegen_unit(&self, tcx: TyCtxt<'_>, cgu_name: InternedString) {
         base::compile_codegen_unit(tcx, cgu_name);
     }
     fn target_machine_factory(
diff --git a/src/librustc_codegen_ssa/back/symbol_export.rs b/src/librustc_codegen_ssa/back/symbol_export.rs
index b9ee82f108ae3..b65e4d24f1b4b 100644
--- a/src/librustc_codegen_ssa/back/symbol_export.rs
+++ b/src/librustc_codegen_ssa/back/symbol_export.rs
@@ -46,10 +46,10 @@ pub fn crates_export_threshold(crate_types: &[config::CrateType]) -> SymbolExpor
     }
 }
 
-fn reachable_non_generics_provider<'tcx>(
-    tcx: TyCtxt<'tcx>,
+fn reachable_non_generics_provider(
+    tcx: TyCtxt<'_>,
     cnum: CrateNum,
-) -> &'tcx DefIdMap<SymbolExportLevel> {
+) -> &DefIdMap<SymbolExportLevel> {
     assert_eq!(cnum, LOCAL_CRATE);
 
     if !tcx.sess.opts.output_types.should_codegen() {
@@ -157,7 +157,7 @@ fn reachable_non_generics_provider<'tcx>(
     tcx.arena.alloc(reachable_non_generics)
 }
 
-fn is_reachable_non_generic_provider_local<'tcx>(tcx: TyCtxt<'tcx>, def_id: DefId) -> bool {
+fn is_reachable_non_generic_provider_local(tcx: TyCtxt<'_>, def_id: DefId) -> bool {
     let export_threshold = threshold(tcx);
 
     if let Some(&level) = tcx.reachable_non_generics(def_id.krate).get(&def_id) {
@@ -167,14 +167,14 @@ fn is_reachable_non_generic_provider_local<'tcx>(tcx: TyCtxt<'tcx>, def_id: DefI
     }
 }
 
-fn is_reachable_non_generic_provider_extern<'tcx>(tcx: TyCtxt<'tcx>, def_id: DefId) -> bool {
+fn is_reachable_non_generic_provider_extern(tcx: TyCtxt<'_>, def_id: DefId) -> bool {
     tcx.reachable_non_generics(def_id.krate).contains_key(&def_id)
 }
 
-fn exported_symbols_provider_local<'tcx>(
-    tcx: TyCtxt<'tcx>,
+fn exported_symbols_provider_local(
+    tcx: TyCtxt<'_>,
     cnum: CrateNum,
-) -> Arc<Vec<(ExportedSymbol<'tcx>, SymbolExportLevel)>> {
+) -> Arc<Vec<(ExportedSymbol<'_>, SymbolExportLevel)>> {
     assert_eq!(cnum, LOCAL_CRATE);
 
     if !tcx.sess.opts.output_types.should_codegen() {
@@ -273,10 +273,10 @@ fn exported_symbols_provider_local<'tcx>(
     Arc::new(symbols)
 }
 
-fn upstream_monomorphizations_provider<'tcx>(
-    tcx: TyCtxt<'tcx>,
+fn upstream_monomorphizations_provider(
+    tcx: TyCtxt<'_>,
     cnum: CrateNum,
-) -> &'tcx DefIdMap<FxHashMap<SubstsRef<'tcx>, CrateNum>> {
+) -> &DefIdMap<FxHashMap<SubstsRef<'_>, CrateNum>> {
     debug_assert!(cnum == LOCAL_CRATE);
 
     let cnums = tcx.all_crate_nums(LOCAL_CRATE);
@@ -322,10 +322,10 @@ fn upstream_monomorphizations_provider<'tcx>(
     tcx.arena.alloc(instances)
 }
 
-fn upstream_monomorphizations_for_provider<'tcx>(
-    tcx: TyCtxt<'tcx>,
+fn upstream_monomorphizations_for_provider(
+    tcx: TyCtxt<'_>,
     def_id: DefId,
-) -> Option<&'tcx FxHashMap<SubstsRef<'tcx>, CrateNum>> {
+) -> Option<&FxHashMap<SubstsRef<'_>, CrateNum>> {
     debug_assert!(!def_id.is_local());
     tcx.upstream_monomorphizations(LOCAL_CRATE).get(&def_id)
 }
diff --git a/src/librustc_codegen_ssa/base.rs b/src/librustc_codegen_ssa/base.rs
index 47b383fddbc31..d06460fc85696 100644
--- a/src/librustc_codegen_ssa/base.rs
+++ b/src/librustc_codegen_ssa/base.rs
@@ -700,7 +700,7 @@ impl<B: ExtraBackendMethods> Drop for AbortCodegenOnDrop<B> {
     }
 }
 
-fn assert_and_save_dep_graph<'tcx>(tcx: TyCtxt<'tcx>) {
+fn assert_and_save_dep_graph(tcx: TyCtxt<'_>) {
     time(tcx.sess,
          "assert dep graph",
          || ::rustc_incremental::assert_dep_graph(tcx));
diff --git a/src/librustc_codegen_ssa/debuginfo/mod.rs b/src/librustc_codegen_ssa/debuginfo/mod.rs
index d60a2e0cb1358..c9b1c0260e8c3 100644
--- a/src/librustc_codegen_ssa/debuginfo/mod.rs
+++ b/src/librustc_codegen_ssa/debuginfo/mod.rs
@@ -10,7 +10,7 @@ pub enum FunctionDebugContext<D> {
 }
 
 impl<D> FunctionDebugContext<D> {
-    pub fn get_ref<'a>(&'a self, span: Span) -> &'a FunctionDebugContextData<D> {
+    pub fn get_ref(&self, span: Span) -> &FunctionDebugContextData<D> {
         match *self {
             FunctionDebugContext::RegularContext(ref data) => data,
             FunctionDebugContext::DebugInfoDisabled => {
diff --git a/src/librustc_codegen_ssa/mir/analyze.rs b/src/librustc_codegen_ssa/mir/analyze.rs
index 0289150a5e42a..2af9b448ef1eb 100644
--- a/src/librustc_codegen_ssa/mir/analyze.rs
+++ b/src/librustc_codegen_ssa/mir/analyze.rs
@@ -273,7 +273,7 @@ impl CleanupKind {
     }
 }
 
-pub fn cleanup_kinds<'tcx>(mir: &mir::Body<'tcx>) -> IndexVec<mir::BasicBlock, CleanupKind> {
+pub fn cleanup_kinds(mir: &mir::Body<'_>) -> IndexVec<mir::BasicBlock, CleanupKind> {
     fn discover_masters<'tcx>(result: &mut IndexVec<mir::BasicBlock, CleanupKind>,
                               mir: &mir::Body<'tcx>) {
         for (bb, data) in mir.basic_blocks().iter_enumerated() {
diff --git a/src/librustc_codegen_ssa/traits/backend.rs b/src/librustc_codegen_ssa/traits/backend.rs
index 414871be6116e..9d5aaa7655db8 100644
--- a/src/librustc_codegen_ssa/traits/backend.rs
+++ b/src/librustc_codegen_ssa/traits/backend.rs
@@ -44,7 +44,7 @@ pub trait ExtraBackendMethods: CodegenBackend + WriteBackendMethods + Sized + Se
         mods: &mut Self::Module,
         kind: AllocatorKind,
     );
-    fn compile_codegen_unit<'tcx>(&self, tcx: TyCtxt<'tcx>, cgu_name: InternedString);
+    fn compile_codegen_unit(&self, tcx: TyCtxt<'_>, cgu_name: InternedString);
     // If find_features is true this won't access `sess.crate_types` by assuming
     // that `is_pie_binary` is false. When we discover LLVM target features
     // `sess.crate_types` is uninitialized so we cannot access it.
diff --git a/src/librustc_codegen_ssa/traits/builder.rs b/src/librustc_codegen_ssa/traits/builder.rs
index 1c80e614db8d5..3a144f0b0e0aa 100644
--- a/src/librustc_codegen_ssa/traits/builder.rs
+++ b/src/librustc_codegen_ssa/traits/builder.rs
@@ -36,7 +36,7 @@ pub trait BuilderMethods<'a, 'tcx>:
 {
     fn new_block<'b>(cx: &'a Self::CodegenCx, llfn: Self::Value, name: &'b str) -> Self;
     fn with_cx(cx: &'a Self::CodegenCx) -> Self;
-    fn build_sibling_block<'b>(&self, name: &'b str) -> Self;
+    fn build_sibling_block(&self, name: &str) -> Self;
     fn cx(&self) -> &Self::CodegenCx;
     fn llbb(&self) -> Self::BasicBlock;
 
diff --git a/src/librustc_codegen_utils/symbol_names_test.rs b/src/librustc_codegen_utils/symbol_names_test.rs
index f48d1f2853c52..7ab29c5c4c3d0 100644
--- a/src/librustc_codegen_utils/symbol_names_test.rs
+++ b/src/librustc_codegen_utils/symbol_names_test.rs
@@ -11,7 +11,7 @@ use syntax::symbol::{Symbol, sym};
 const SYMBOL_NAME: Symbol = sym::rustc_symbol_name;
 const DEF_PATH: Symbol = sym::rustc_def_path;
 
-pub fn report_symbol_names<'tcx>(tcx: TyCtxt<'tcx>) {
+pub fn report_symbol_names(tcx: TyCtxt<'_>) {
     // if the `rustc_attrs` feature is not enabled, then the
     // attributes we are interested in cannot be present anyway, so
     // skip the walk.
diff --git a/src/librustc_data_structures/bit_set.rs b/src/librustc_data_structures/bit_set.rs
index 5d8388d89f5b3..1eb28bccbe382 100644
--- a/src/librustc_data_structures/bit_set.rs
+++ b/src/librustc_data_structures/bit_set.rs
@@ -168,7 +168,7 @@ impl<T: Idx> BitSet<T> {
 
     /// Iterates over the indices of set bits in a sorted order.
     #[inline]
-    pub fn iter<'a>(&'a self) -> BitIter<'a, T> {
+    pub fn iter(&self) -> BitIter<'_, T> {
         BitIter {
             cur: None,
             iter: self.words.iter().enumerate(),
@@ -849,7 +849,7 @@ impl<R: Idx, C: Idx> BitMatrix<R, C> {
 
     /// Iterates through all the columns set to true in a given row of
     /// the matrix.
-    pub fn iter<'a>(&'a self, row: R) -> BitIter<'a, C> {
+    pub fn iter(&self, row: R) -> BitIter<'_, C> {
         assert!(row.index() < self.num_rows);
         let (start, end) = self.range(row);
         BitIter {
diff --git a/src/librustc_data_structures/fingerprint.rs b/src/librustc_data_structures/fingerprint.rs
index 7975c62b90fb6..3bea965ef3041 100644
--- a/src/librustc_data_structures/fingerprint.rs
+++ b/src/librustc_data_structures/fingerprint.rs
@@ -58,7 +58,7 @@ impl Fingerprint {
         Ok(())
     }
 
-    pub fn decode_opaque<'a>(decoder: &mut Decoder<'a>) -> Result<Fingerprint, String> {
+    pub fn decode_opaque(decoder: &mut Decoder<'_>) -> Result<Fingerprint, String> {
         let mut bytes = [0; 16];
 
         decoder.read_raw_bytes(&mut bytes)?;
diff --git a/src/librustc_data_structures/graph/implementation/mod.rs b/src/librustc_data_structures/graph/implementation/mod.rs
index de4b1bcd0c2a1..d2699004c81d8 100644
--- a/src/librustc_data_structures/graph/implementation/mod.rs
+++ b/src/librustc_data_structures/graph/implementation/mod.rs
@@ -247,11 +247,11 @@ impl<N: Debug, E: Debug> Graph<N, E> {
         self.incoming_edges(target).sources()
     }
 
-    pub fn depth_traverse<'a>(
-        &'a self,
+    pub fn depth_traverse(
+        &self,
         start: NodeIndex,
         direction: Direction,
-    ) -> DepthFirstTraversal<'a, N, E> {
+    ) -> DepthFirstTraversal<'_, N, E> {
         DepthFirstTraversal::with_start_node(self, start, direction)
     }
 
diff --git a/src/librustc_data_structures/graph/mod.rs b/src/librustc_data_structures/graph/mod.rs
index 3d47b7d49fb96..3158aafc09134 100644
--- a/src/librustc_data_structures/graph/mod.rs
+++ b/src/librustc_data_structures/graph/mod.rs
@@ -21,10 +21,10 @@ pub trait WithSuccessors: DirectedGraph
 where
     Self: for<'graph> GraphSuccessors<'graph, Item = <Self as DirectedGraph>::Node>,
 {
-    fn successors<'graph>(
-        &'graph self,
+    fn successors(
+        &self,
         node: Self::Node,
-    ) -> <Self as GraphSuccessors<'graph>>::Iter;
+    ) -> <Self as GraphSuccessors<'_>>::Iter;
 }
 
 pub trait GraphSuccessors<'graph> {
@@ -36,10 +36,10 @@ pub trait WithPredecessors: DirectedGraph
 where
     Self: for<'graph> GraphPredecessors<'graph, Item = <Self as DirectedGraph>::Node>,
 {
-    fn predecessors<'graph>(
-        &'graph self,
+    fn predecessors(
+        &self,
         node: Self::Node,
-    ) -> <Self as GraphPredecessors<'graph>>::Iter;
+    ) -> <Self as GraphPredecessors<'_>>::Iter;
 }
 
 pub trait GraphPredecessors<'graph> {
diff --git a/src/librustc_data_structures/graph/reference.rs b/src/librustc_data_structures/graph/reference.rs
index 5ad2a71e1d732..9442bb3cdec3b 100644
--- a/src/librustc_data_structures/graph/reference.rs
+++ b/src/librustc_data_structures/graph/reference.rs
@@ -17,15 +17,15 @@ impl<'graph, G: WithStartNode> WithStartNode for &'graph G {
 }
 
 impl<'graph, G: WithSuccessors> WithSuccessors for &'graph G {
-    fn successors<'iter>(&'iter self, node: Self::Node) -> <Self as GraphSuccessors<'iter>>::Iter {
+    fn successors(&self, node: Self::Node) -> <Self as GraphSuccessors<'_>>::Iter {
         (**self).successors(node)
     }
 }
 
 impl<'graph, G: WithPredecessors> WithPredecessors for &'graph G {
-    fn predecessors<'iter>(&'iter self,
-                           node: Self::Node)
-                           -> <Self as GraphPredecessors<'iter>>::Iter {
+    fn predecessors(&self,
+                    node: Self::Node)
+                    -> <Self as GraphPredecessors<'_>>::Iter {
         (**self).predecessors(node)
     }
 }
diff --git a/src/librustc_data_structures/graph/test.rs b/src/librustc_data_structures/graph/test.rs
index b390c41957294..bc142144e930f 100644
--- a/src/librustc_data_structures/graph/test.rs
+++ b/src/librustc_data_structures/graph/test.rs
@@ -51,15 +51,15 @@ impl WithNumNodes for TestGraph {
 }
 
 impl WithPredecessors for TestGraph {
-    fn predecessors<'graph>(&'graph self,
-                            node: usize)
-                            -> <Self as GraphPredecessors<'graph>>::Iter {
+    fn predecessors(&self,
+                    node: usize)
+                    -> <Self as GraphPredecessors<'_>>::Iter {
         self.predecessors[&node].iter().cloned()
     }
 }
 
 impl WithSuccessors for TestGraph {
-    fn successors<'graph>(&'graph self, node: usize) -> <Self as GraphSuccessors<'graph>>::Iter {
+    fn successors(&self, node: usize) -> <Self as GraphSuccessors<'_>>::Iter {
         self.successors[&node].iter().cloned()
     }
 }
diff --git a/src/librustc_driver/pretty.rs b/src/librustc_driver/pretty.rs
index d92f3aafa1c7e..ff0c4ff548b71 100644
--- a/src/librustc_driver/pretty.rs
+++ b/src/librustc_driver/pretty.rs
@@ -188,7 +188,7 @@ impl PpSourceMode {
             _ => panic!("Should use call_with_pp_support_hir"),
         }
     }
-    fn call_with_pp_support_hir<'tcx, A, F>(&self, tcx: TyCtxt<'tcx>, f: F) -> A
+    fn call_with_pp_support_hir<A, F>(&self, tcx: TyCtxt<'_>, f: F) -> A
     where
         F: FnOnce(&dyn HirPrinterSupport<'_>, &hir::Crate) -> A,
     {
@@ -228,7 +228,7 @@ impl PpSourceMode {
 trait PrinterSupport: pprust::PpAnn {
     /// Provides a uniform interface for re-extracting a reference to a
     /// `Session` from a value that now owns it.
-    fn sess<'a>(&'a self) -> &'a Session;
+    fn sess(&self) -> &Session;
 
     /// Produces the pretty-print annotation object.
     ///
@@ -240,7 +240,7 @@ trait PrinterSupport: pprust::PpAnn {
 trait HirPrinterSupport<'hir>: pprust_hir::PpAnn {
     /// Provides a uniform interface for re-extracting a reference to a
     /// `Session` from a value that now owns it.
-    fn sess<'a>(&'a self) -> &'a Session;
+    fn sess(&self) -> &Session;
 
     /// Provides a uniform interface for re-extracting a reference to an
     /// `hir_map::Map` from a value that now owns it.
@@ -272,7 +272,7 @@ struct NoAnn<'hir> {
 }
 
 impl<'hir> PrinterSupport for NoAnn<'hir> {
-    fn sess<'a>(&'a self) -> &'a Session {
+    fn sess(&self) -> &Session {
         self.sess
     }
 
@@ -282,7 +282,7 @@ impl<'hir> PrinterSupport for NoAnn<'hir> {
 }
 
 impl<'hir> HirPrinterSupport<'hir> for NoAnn<'hir> {
-    fn sess<'a>(&'a self) -> &'a Session {
+    fn sess(&self) -> &Session {
         self.sess
     }
 
@@ -313,7 +313,7 @@ struct IdentifiedAnnotation<'hir> {
 }
 
 impl<'hir> PrinterSupport for IdentifiedAnnotation<'hir> {
-    fn sess<'a>(&'a self) -> &'a Session {
+    fn sess(&self) -> &Session {
         self.sess
     }
 
@@ -360,7 +360,7 @@ impl<'hir> pprust::PpAnn for IdentifiedAnnotation<'hir> {
 }
 
 impl<'hir> HirPrinterSupport<'hir> for IdentifiedAnnotation<'hir> {
-    fn sess<'a>(&'a self) -> &'a Session {
+    fn sess(&self) -> &Session {
         self.sess
     }
 
@@ -458,7 +458,7 @@ struct TypedAnnotation<'a, 'tcx> {
 }
 
 impl<'b, 'tcx> HirPrinterSupport<'tcx> for TypedAnnotation<'b, 'tcx> {
-    fn sess<'a>(&'a self) -> &'a Session {
+    fn sess(&self) -> &Session {
         &self.tcx.sess
     }
 
@@ -866,8 +866,8 @@ pub fn print_after_hir_lowering<'tcx>(
 // analysis is performed. However, we want to call `phase_3_run_analysis_passes`
 // with a different callback than the standard driver, so that isn't easy.
 // Instead, we call that function ourselves.
-fn print_with_analysis<'tcx>(
-    tcx: TyCtxt<'tcx>,
+fn print_with_analysis(
+    tcx: TyCtxt<'_>,
     ppm: PpMode,
     uii: Option<UserIdentifiedItem>,
     ofile: Option<&Path>,
diff --git a/src/librustc_errors/emitter.rs b/src/librustc_errors/emitter.rs
index a2717ab7ad8a9..83a0fb486fd9a 100644
--- a/src/librustc_errors/emitter.rs
+++ b/src/librustc_errors/emitter.rs
@@ -1635,7 +1635,7 @@ impl Destination {
         }
     }
 
-    fn writable<'a>(&'a mut self) -> WritableDst<'a> {
+    fn writable(&mut self) -> WritableDst<'_> {
         match *self {
             Destination::Terminal(ref mut t) => WritableDst::Terminal(t),
             Destination::Buffered(ref mut t) => {
diff --git a/src/librustc_errors/lib.rs b/src/librustc_errors/lib.rs
index 70bd25a9d5772..1ffee1cdf691f 100644
--- a/src/librustc_errors/lib.rs
+++ b/src/librustc_errors/lib.rs
@@ -438,14 +438,14 @@ impl Handler {
         self.err_count.store(0, SeqCst);
     }
 
-    pub fn struct_dummy<'a>(&'a self) -> DiagnosticBuilder<'a> {
+    pub fn struct_dummy(&self) -> DiagnosticBuilder<'_> {
         DiagnosticBuilder::new(self, Level::Cancelled, "")
     }
 
-    pub fn struct_span_warn<'a, S: Into<MultiSpan>>(&'a self,
-                                                    sp: S,
-                                                    msg: &str)
-                                                    -> DiagnosticBuilder<'a> {
+    pub fn struct_span_warn<S: Into<MultiSpan>>(&self,
+                                                sp: S,
+                                                msg: &str)
+                                                -> DiagnosticBuilder<'_> {
         let mut result = DiagnosticBuilder::new(self, Level::Warning, msg);
         result.set_span(sp);
         if !self.flags.can_emit_warnings {
@@ -453,11 +453,11 @@ impl Handler {
         }
         result
     }
-    pub fn struct_span_warn_with_code<'a, S: Into<MultiSpan>>(&'a self,
-                                                              sp: S,
-                                                              msg: &str,
-                                                              code: DiagnosticId)
-                                                              -> DiagnosticBuilder<'a> {
+    pub fn struct_span_warn_with_code<S: Into<MultiSpan>>(&self,
+                                                          sp: S,
+                                                          msg: &str,
+                                                          code: DiagnosticId)
+                                                          -> DiagnosticBuilder<'_> {
         let mut result = DiagnosticBuilder::new(self, Level::Warning, msg);
         result.set_span(sp);
         result.code(code);
@@ -466,63 +466,63 @@ impl Handler {
         }
         result
     }
-    pub fn struct_warn<'a>(&'a self, msg: &str) -> DiagnosticBuilder<'a> {
+    pub fn struct_warn(&self, msg: &str) -> DiagnosticBuilder<'_> {
         let mut result = DiagnosticBuilder::new(self, Level::Warning, msg);
         if !self.flags.can_emit_warnings {
             result.cancel();
         }
         result
     }
-    pub fn struct_span_err<'a, S: Into<MultiSpan>>(&'a self,
-                                                   sp: S,
-                                                   msg: &str)
-                                                   -> DiagnosticBuilder<'a> {
+    pub fn struct_span_err<S: Into<MultiSpan>>(&self,
+                                               sp: S,
+                                               msg: &str)
+                                               -> DiagnosticBuilder<'_> {
         let mut result = DiagnosticBuilder::new(self, Level::Error, msg);
         result.set_span(sp);
         result
     }
-    pub fn struct_span_err_with_code<'a, S: Into<MultiSpan>>(&'a self,
-                                                             sp: S,
-                                                             msg: &str,
-                                                             code: DiagnosticId)
-                                                             -> DiagnosticBuilder<'a> {
+    pub fn struct_span_err_with_code<S: Into<MultiSpan>>(&self,
+                                                         sp: S,
+                                                         msg: &str,
+                                                         code: DiagnosticId)
+                                                         -> DiagnosticBuilder<'_> {
         let mut result = DiagnosticBuilder::new(self, Level::Error, msg);
         result.set_span(sp);
         result.code(code);
         result
     }
     // FIXME: This method should be removed (every error should have an associated error code).
-    pub fn struct_err<'a>(&'a self, msg: &str) -> DiagnosticBuilder<'a> {
+    pub fn struct_err(&self, msg: &str) -> DiagnosticBuilder<'_> {
         DiagnosticBuilder::new(self, Level::Error, msg)
     }
-    pub fn struct_err_with_code<'a>(
-        &'a self,
+    pub fn struct_err_with_code(
+        &self,
         msg: &str,
         code: DiagnosticId,
-    ) -> DiagnosticBuilder<'a> {
+    ) -> DiagnosticBuilder<'_> {
         let mut result = DiagnosticBuilder::new(self, Level::Error, msg);
         result.code(code);
         result
     }
-    pub fn struct_span_fatal<'a, S: Into<MultiSpan>>(&'a self,
-                                                     sp: S,
-                                                     msg: &str)
-                                                     -> DiagnosticBuilder<'a> {
+    pub fn struct_span_fatal<S: Into<MultiSpan>>(&self,
+                                                 sp: S,
+                                                 msg: &str)
+                                                 -> DiagnosticBuilder<'_> {
         let mut result = DiagnosticBuilder::new(self, Level::Fatal, msg);
         result.set_span(sp);
         result
     }
-    pub fn struct_span_fatal_with_code<'a, S: Into<MultiSpan>>(&'a self,
-                                                               sp: S,
-                                                               msg: &str,
-                                                               code: DiagnosticId)
-                                                               -> DiagnosticBuilder<'a> {
+    pub fn struct_span_fatal_with_code<S: Into<MultiSpan>>(&self,
+                                                           sp: S,
+                                                           msg: &str,
+                                                           code: DiagnosticId)
+                                                           -> DiagnosticBuilder<'_> {
         let mut result = DiagnosticBuilder::new(self, Level::Fatal, msg);
         result.set_span(sp);
         result.code(code);
         result
     }
-    pub fn struct_fatal<'a>(&'a self, msg: &str) -> DiagnosticBuilder<'a> {
+    pub fn struct_fatal(&self, msg: &str) -> DiagnosticBuilder<'_> {
         DiagnosticBuilder::new(self, Level::Fatal, msg)
     }
 
@@ -563,10 +563,10 @@ impl Handler {
     pub fn span_err<S: Into<MultiSpan>>(&self, sp: S, msg: &str) {
         self.emit(&sp.into(), msg, Error);
     }
-    pub fn mut_span_err<'a, S: Into<MultiSpan>>(&'a self,
-                                                sp: S,
-                                                msg: &str)
-                                                -> DiagnosticBuilder<'a> {
+    pub fn mut_span_err<S: Into<MultiSpan>>(&self,
+                                            sp: S,
+                                            msg: &str)
+                                            -> DiagnosticBuilder<'_> {
         let mut result = DiagnosticBuilder::new(self, Level::Error, msg);
         result.set_span(sp);
         result
@@ -605,10 +605,10 @@ impl Handler {
     pub fn span_note_without_error<S: Into<MultiSpan>>(&self, sp: S, msg: &str) {
         self.emit(&sp.into(), msg, Note);
     }
-    pub fn span_note_diag<'a>(&'a self,
-                              sp: Span,
-                              msg: &str)
-                              -> DiagnosticBuilder<'a> {
+    pub fn span_note_diag(&self,
+                          sp: Span,
+                          msg: &str)
+                          -> DiagnosticBuilder<'_> {
         let mut db = DiagnosticBuilder::new(self, Note, msg);
         db.set_span(sp);
         db
diff --git a/src/librustc_incremental/assert_dep_graph.rs b/src/librustc_incremental/assert_dep_graph.rs
index a43347a2197c3..38dc6edaf6325 100644
--- a/src/librustc_incremental/assert_dep_graph.rs
+++ b/src/librustc_incremental/assert_dep_graph.rs
@@ -51,7 +51,7 @@ use std::io::Write;
 use syntax::ast;
 use syntax_pos::Span;
 
-pub fn assert_dep_graph<'tcx>(tcx: TyCtxt<'tcx>) {
+pub fn assert_dep_graph(tcx: TyCtxt<'_>) {
     tcx.dep_graph.with_ignore(|| {
         if tcx.sess.opts.debugging_opts.dump_dep_graph {
             dump_graph(tcx);
diff --git a/src/librustc_incremental/assert_module_sources.rs b/src/librustc_incremental/assert_module_sources.rs
index f502d0475460e..046fdc72270db 100644
--- a/src/librustc_incremental/assert_module_sources.rs
+++ b/src/librustc_incremental/assert_module_sources.rs
@@ -35,7 +35,7 @@ const MODULE: Symbol = sym::module;
 const CFG: Symbol = sym::cfg;
 const KIND: Symbol = sym::kind;
 
-pub fn assert_module_sources<'tcx>(tcx: TyCtxt<'tcx>) {
+pub fn assert_module_sources(tcx: TyCtxt<'_>) {
     tcx.dep_graph.with_ignore(|| {
         if tcx.sess.opts.incremental.is_none() {
             return;
diff --git a/src/librustc_incremental/persist/dirty_clean.rs b/src/librustc_incremental/persist/dirty_clean.rs
index 5296ed0ffd0b8..1d83aa112a837 100644
--- a/src/librustc_incremental/persist/dirty_clean.rs
+++ b/src/librustc_incremental/persist/dirty_clean.rs
@@ -206,7 +206,7 @@ impl Assertion {
     }
 }
 
-pub fn check_dirty_clean_annotations<'tcx>(tcx: TyCtxt<'tcx>) {
+pub fn check_dirty_clean_annotations(tcx: TyCtxt<'_>) {
     // can't add `#[rustc_dirty]` etc without opting in to this feature
     if !tcx.features().rustc_attrs {
         return;
diff --git a/src/librustc_incremental/persist/load.rs b/src/librustc_incremental/persist/load.rs
index d9bcc0b2a83c7..90aefb0f32416 100644
--- a/src/librustc_incremental/persist/load.rs
+++ b/src/librustc_incremental/persist/load.rs
@@ -15,7 +15,7 @@ use super::fs::*;
 use super::file_format;
 use super::work_product;
 
-pub fn dep_graph_tcx_init<'tcx>(tcx: TyCtxt<'tcx>) {
+pub fn dep_graph_tcx_init(tcx: TyCtxt<'_>) {
     if !tcx.dep_graph.is_fully_enabled() {
         return
     }
@@ -192,7 +192,7 @@ pub fn load_dep_graph(sess: &Session) -> DepGraphFuture {
     }))
 }
 
-pub fn load_query_result_cache<'sess>(sess: &'sess Session) -> OnDiskCache<'sess> {
+pub fn load_query_result_cache(sess: &Session) -> OnDiskCache<'_> {
     if sess.opts.incremental.is_none() ||
        !sess.opts.debugging_opts.incremental_queries {
         return OnDiskCache::new_empty(sess.source_map());
diff --git a/src/librustc_incremental/persist/save.rs b/src/librustc_incremental/persist/save.rs
index 49c79ec09f5e2..13e2c5d1c574d 100644
--- a/src/librustc_incremental/persist/save.rs
+++ b/src/librustc_incremental/persist/save.rs
@@ -15,7 +15,7 @@ use super::dirty_clean;
 use super::file_format;
 use super::work_product;
 
-pub fn save_dep_graph<'tcx>(tcx: TyCtxt<'tcx>) {
+pub fn save_dep_graph(tcx: TyCtxt<'_>) {
     debug!("save_dep_graph()");
     tcx.dep_graph.with_ignore(|| {
         let sess = tcx.sess;
diff --git a/src/librustc_interface/passes.rs b/src/librustc_interface/passes.rs
index c1b6e3409c915..d698728198130 100644
--- a/src/librustc_interface/passes.rs
+++ b/src/librustc_interface/passes.rs
@@ -878,7 +878,7 @@ pub fn create_global_ctxt(
 
 /// Runs the resolution, type-checking, region checking and other
 /// miscellaneous analysis passes on the crate.
-fn analysis<'tcx>(tcx: TyCtxt<'tcx>, cnum: CrateNum) -> Result<()> {
+fn analysis(tcx: TyCtxt<'_>, cnum: CrateNum) -> Result<()> {
     assert_eq!(cnum, LOCAL_CRATE);
 
     let sess = tcx.sess;
@@ -995,8 +995,8 @@ fn analysis<'tcx>(tcx: TyCtxt<'tcx>, cnum: CrateNum) -> Result<()> {
     Ok(())
 }
 
-fn encode_and_write_metadata<'tcx>(
-    tcx: TyCtxt<'tcx>,
+fn encode_and_write_metadata(
+    tcx: TyCtxt<'_>,
     outputs: &OutputFilenames,
 ) -> (middle::cstore::EncodedMetadata, bool) {
     #[derive(PartialEq, Eq, PartialOrd, Ord)]
diff --git a/src/librustc_interface/proc_macro_decls.rs b/src/librustc_interface/proc_macro_decls.rs
index 9e1ef6b022d9b..d888c9e57d326 100644
--- a/src/librustc_interface/proc_macro_decls.rs
+++ b/src/librustc_interface/proc_macro_decls.rs
@@ -6,11 +6,11 @@ use rustc::ty::query::Providers;
 use syntax::attr;
 use syntax::symbol::sym;
 
-pub fn find<'tcx>(tcx: TyCtxt<'tcx>) -> Option<DefId> {
+pub fn find(tcx: TyCtxt<'_>) -> Option<DefId> {
     tcx.proc_macro_decls_static(LOCAL_CRATE)
 }
 
-fn proc_macro_decls_static<'tcx>(tcx: TyCtxt<'tcx>, cnum: CrateNum) -> Option<DefId> {
+fn proc_macro_decls_static(tcx: TyCtxt<'_>, cnum: CrateNum) -> Option<DefId> {
     assert_eq!(cnum, LOCAL_CRATE);
 
     let mut finder = Finder { decls: None };
diff --git a/src/librustc_lint/lib.rs b/src/librustc_lint/lib.rs
index e13277f1b9a49..951c7b6d7213e 100644
--- a/src/librustc_lint/lib.rs
+++ b/src/librustc_lint/lib.rs
@@ -76,7 +76,7 @@ pub fn provide(providers: &mut Providers<'_>) {
     };
 }
 
-fn lint_mod<'tcx>(tcx: TyCtxt<'tcx>, module_def_id: DefId) {
+fn lint_mod(tcx: TyCtxt<'_>, module_def_id: DefId) {
     lint::late_lint_mod(tcx, module_def_id, BuiltinCombinedModuleLateLintPass::new());
 }
 
diff --git a/src/librustc_metadata/cstore_impl.rs b/src/librustc_metadata/cstore_impl.rs
index 04a9c4e9a1a11..914084d7e9ece 100644
--- a/src/librustc_metadata/cstore_impl.rs
+++ b/src/librustc_metadata/cstore_impl.rs
@@ -250,7 +250,7 @@ provide! { <'tcx> tcx, def_id, other, cdata,
     exported_symbols => { Arc::new(cdata.exported_symbols(tcx)) }
 }
 
-pub fn provide<'tcx>(providers: &mut Providers<'tcx>) {
+pub fn provide(providers: &mut Providers<'_>) {
     // FIXME(#44234) - almost all of these queries have no sub-queries and
     // therefore no actual inputs, they're just reading tables calculated in
     // resolve! Does this work? Unsure! That's what the issue is about
@@ -550,7 +550,7 @@ impl CrateStore for cstore::CStore {
         self.do_postorder_cnums_untracked()
     }
 
-    fn encode_metadata<'tcx>(&self, tcx: TyCtxt<'tcx>) -> EncodedMetadata {
+    fn encode_metadata(&self, tcx: TyCtxt<'_>) -> EncodedMetadata {
         encoder::encode_metadata(tcx)
     }
 
diff --git a/src/librustc_metadata/encoder.rs b/src/librustc_metadata/encoder.rs
index b52b6dfbb5e12..73c20ccad5abf 100644
--- a/src/librustc_metadata/encoder.rs
+++ b/src/librustc_metadata/encoder.rs
@@ -1863,7 +1863,7 @@ impl<'tcx, 'v> ItemLikeVisitor<'v> for ImplVisitor<'tcx> {
 // will allow us to slice the metadata to the precise length that we just
 // generated regardless of trailing bytes that end up in it.
 
-pub fn encode_metadata<'tcx>(tcx: TyCtxt<'tcx>) -> EncodedMetadata {
+pub fn encode_metadata(tcx: TyCtxt<'_>) -> EncodedMetadata {
     let mut encoder = opaque::Encoder::new(vec![]);
     encoder.emit_raw_bytes(METADATA_HEADER);
 
@@ -1905,7 +1905,7 @@ pub fn encode_metadata<'tcx>(tcx: TyCtxt<'tcx>) -> EncodedMetadata {
     EncodedMetadata { raw_data: result }
 }
 
-pub fn get_repr_options<'tcx>(tcx: TyCtxt<'tcx>, did: DefId) -> ReprOptions {
+pub fn get_repr_options(tcx: TyCtxt<'_>, did: DefId) -> ReprOptions {
     let ty = tcx.type_of(did);
     match ty.sty {
         ty::Adt(ref def, _) => return def.repr,
diff --git a/src/librustc_metadata/foreign_modules.rs b/src/librustc_metadata/foreign_modules.rs
index 0ce103cfa40dc..b1f4dfffc7898 100644
--- a/src/librustc_metadata/foreign_modules.rs
+++ b/src/librustc_metadata/foreign_modules.rs
@@ -3,7 +3,7 @@ use rustc::hir;
 use rustc::middle::cstore::ForeignModule;
 use rustc::ty::TyCtxt;
 
-pub fn collect<'tcx>(tcx: TyCtxt<'tcx>) -> Vec<ForeignModule> {
+pub fn collect(tcx: TyCtxt<'_>) -> Vec<ForeignModule> {
     let mut collector = Collector {
         tcx,
         modules: Vec::new(),
diff --git a/src/librustc_metadata/link_args.rs b/src/librustc_metadata/link_args.rs
index cd6270046faab..728fd004fcb69 100644
--- a/src/librustc_metadata/link_args.rs
+++ b/src/librustc_metadata/link_args.rs
@@ -4,7 +4,7 @@ use rustc::ty::TyCtxt;
 use rustc_target::spec::abi::Abi;
 use syntax::symbol::sym;
 
-pub fn collect<'tcx>(tcx: TyCtxt<'tcx>) -> Vec<String> {
+pub fn collect(tcx: TyCtxt<'_>) -> Vec<String> {
     let mut collector = Collector {
         args: Vec::new(),
     };
diff --git a/src/librustc_metadata/native_libs.rs b/src/librustc_metadata/native_libs.rs
index 7b335b3b4832d..4a01d0e559af4 100644
--- a/src/librustc_metadata/native_libs.rs
+++ b/src/librustc_metadata/native_libs.rs
@@ -11,7 +11,7 @@ use syntax::feature_gate::{self, GateIssue};
 use syntax::symbol::{Symbol, sym};
 use syntax::{span_err, struct_span_err};
 
-pub fn collect<'tcx>(tcx: TyCtxt<'tcx>) -> Vec<NativeLibrary> {
+pub fn collect(tcx: TyCtxt<'_>) -> Vec<NativeLibrary> {
     let mut collector = Collector {
         tcx,
         libs: Vec::new(),
diff --git a/src/librustc_mir/borrow_check/mod.rs b/src/librustc_mir/borrow_check/mod.rs
index 4872440f5bd4a..0072fcb22f13e 100644
--- a/src/librustc_mir/borrow_check/mod.rs
+++ b/src/librustc_mir/borrow_check/mod.rs
@@ -87,7 +87,7 @@ pub fn provide(providers: &mut Providers<'_>) {
     };
 }
 
-fn mir_borrowck<'tcx>(tcx: TyCtxt<'tcx>, def_id: DefId) -> BorrowCheckResult<'tcx> {
+fn mir_borrowck(tcx: TyCtxt<'_>, def_id: DefId) -> BorrowCheckResult<'_> {
     let input_body = tcx.mir_validated(def_id);
     debug!("run query mir_borrowck: {}", tcx.def_path_str(def_id));
 
diff --git a/src/librustc_mir/borrow_check/nll/constraints/graph.rs b/src/librustc_mir/borrow_check/nll/constraints/graph.rs
index c4b2a5daef89a..081dc8c7e7188 100644
--- a/src/librustc_mir/borrow_check/nll/constraints/graph.rs
+++ b/src/librustc_mir/borrow_check/nll/constraints/graph.rs
@@ -234,10 +234,10 @@ impl<'s, D: ConstraintGraphDirecton> graph::WithNumNodes for RegionGraph<'s, D>
 }
 
 impl<'s, D: ConstraintGraphDirecton> graph::WithSuccessors for RegionGraph<'s, D> {
-    fn successors<'graph>(
-        &'graph self,
+    fn successors(
+        &self,
         node: Self::Node,
-    ) -> <Self as graph::GraphSuccessors<'graph>>::Iter {
+    ) -> <Self as graph::GraphSuccessors<'_>>::Iter {
         self.outgoing_regions(node)
     }
 }
diff --git a/src/librustc_mir/borrow_check/nll/region_infer/values.rs b/src/librustc_mir/borrow_check/nll/region_infer/values.rs
index cfd80cecca510..6f9f5707935ba 100644
--- a/src/librustc_mir/borrow_check/nll/region_infer/values.rs
+++ b/src/librustc_mir/borrow_check/nll/region_infer/values.rs
@@ -162,7 +162,7 @@ impl<N: Idx> LivenessValues<N> {
     }
 
     /// Iterate through each region that has a value in this set.
-    crate fn rows<'a>(&'a self) -> impl Iterator<Item = N> {
+    crate fn rows(&self) -> impl Iterator<Item=N> {
         self.points.rows()
     }
 
diff --git a/src/librustc_mir/borrow_check/path_utils.rs b/src/librustc_mir/borrow_check/path_utils.rs
index aa2b177e54ed8..538ac6881d90a 100644
--- a/src/librustc_mir/borrow_check/path_utils.rs
+++ b/src/librustc_mir/borrow_check/path_utils.rs
@@ -130,7 +130,7 @@ pub(super) fn is_active<'tcx>(
 
 /// Determines if a given borrow is borrowing local data
 /// This is called for all Yield statements on movable generators
-pub(super) fn borrow_of_local_data<'tcx>(place: &Place<'tcx>) -> bool {
+pub(super) fn borrow_of_local_data(place: &Place<'_>) -> bool {
     place.iterate(|place_base, place_projection| {
         match place_base {
             PlaceBase::Static(..) => return false,
diff --git a/src/librustc_mir/build/expr/category.rs b/src/librustc_mir/build/expr/category.rs
index 222ce6d1c968e..f679a00035d76 100644
--- a/src/librustc_mir/build/expr/category.rs
+++ b/src/librustc_mir/build/expr/category.rs
@@ -31,7 +31,7 @@ pub enum RvalueFunc {
 /// Determines the category for a given expression. Note that scope
 /// and paren expressions have no category.
 impl Category {
-    pub fn of<'tcx>(ek: &ExprKind<'tcx>) -> Option<Category> {
+    pub fn of(ek: &ExprKind<'_>) -> Option<Category> {
         match *ek {
             ExprKind::Scope { .. } => None,
 
diff --git a/src/librustc_mir/build/matches/test.rs b/src/librustc_mir/build/matches/test.rs
index 95e2e52092a91..528dfbef6946a 100644
--- a/src/librustc_mir/build/matches/test.rs
+++ b/src/librustc_mir/build/matches/test.rs
@@ -826,6 +826,6 @@ impl Test<'_> {
     }
 }
 
-fn is_switch_ty<'tcx>(ty: Ty<'tcx>) -> bool {
+fn is_switch_ty(ty: Ty<'_>) -> bool {
     ty.is_integral() || ty.is_char() || ty.is_bool()
 }
diff --git a/src/librustc_mir/build/mod.rs b/src/librustc_mir/build/mod.rs
index ad970de466cfd..80a035d8287f4 100644
--- a/src/librustc_mir/build/mod.rs
+++ b/src/librustc_mir/build/mod.rs
@@ -22,7 +22,7 @@ use syntax_pos::Span;
 use super::lints;
 
 /// Construct the MIR for a given `DefId`.
-pub fn mir_build<'tcx>(tcx: TyCtxt<'tcx>, def_id: DefId) -> Body<'tcx> {
+pub fn mir_build(tcx: TyCtxt<'_>, def_id: DefId) -> Body<'_> {
     let id = tcx.hir().as_local_hir_id(def_id).unwrap();
 
     // Figure out what primary body this item has.
@@ -171,11 +171,11 @@ pub fn mir_build<'tcx>(tcx: TyCtxt<'tcx>, def_id: DefId) -> Body<'tcx> {
 ///////////////////////////////////////////////////////////////////////////
 // BuildMir -- walks a crate, looking for fn items and methods to build MIR from
 
-fn liberated_closure_env_ty<'tcx>(
-    tcx: TyCtxt<'tcx>,
+fn liberated_closure_env_ty(
+    tcx: TyCtxt<'_>,
     closure_expr_id: hir::HirId,
     body_id: hir::BodyId,
-) -> Ty<'tcx> {
+) -> Ty<'_> {
     let closure_ty = tcx.body_tables(body_id).node_type(closure_expr_id);
 
     let (closure_def_id, closure_substs) = match closure_ty.sty {
@@ -485,7 +485,7 @@ macro_rules! unpack {
     };
 }
 
-fn should_abort_on_panic<'tcx>(tcx: TyCtxt<'tcx>, fn_def_id: DefId, abi: Abi) -> bool {
+fn should_abort_on_panic(tcx: TyCtxt<'_>, fn_def_id: DefId, abi: Abi) -> bool {
     // Not callable from C, so we can safely unwind through these
     if abi == Abi::Rust || abi == Abi::RustCall { return false; }
 
diff --git a/src/librustc_mir/dataflow/impls/borrowed_locals.rs b/src/librustc_mir/dataflow/impls/borrowed_locals.rs
index 0f7f37f2db8b4..d94ebdbae24ae 100644
--- a/src/librustc_mir/dataflow/impls/borrowed_locals.rs
+++ b/src/librustc_mir/dataflow/impls/borrowed_locals.rs
@@ -92,7 +92,7 @@ struct BorrowedLocalsVisitor<'gk> {
     trans: &'gk mut GenKillSet<Local>,
 }
 
-fn find_local<'tcx>(place: &Place<'tcx>) -> Option<Local> {
+fn find_local(place: &Place<'_>) -> Option<Local> {
     place.iterate(|place_base, place_projection| {
         for proj in place_projection {
             if proj.elem == ProjectionElem::Deref {
diff --git a/src/librustc_mir/hair/pattern/_match.rs b/src/librustc_mir/hair/pattern/_match.rs
index fc2951895f3fe..d356194c00343 100644
--- a/src/librustc_mir/hair/pattern/_match.rs
+++ b/src/librustc_mir/hair/pattern/_match.rs
@@ -835,7 +835,7 @@ impl<'tcx> IntRange<'tcx> {
     fn from_ctor(tcx: TyCtxt<'tcx>, ctor: &Constructor<'tcx>) -> Option<IntRange<'tcx>> {
         // Floating-point ranges are permitted and we don't want
         // to consider them when constructing integer ranges.
-        fn is_integral<'tcx>(ty: Ty<'tcx>) -> bool {
+        fn is_integral(ty: Ty<'_>) -> bool {
             match ty.sty {
                 ty::Char | ty::Int(_) | ty::Uint(_) => true,
                 _ => false,
diff --git a/src/librustc_mir/hair/pattern/check_match.rs b/src/librustc_mir/hair/pattern/check_match.rs
index f8baf457e9d2c..915ce9f20d07d 100644
--- a/src/librustc_mir/hair/pattern/check_match.rs
+++ b/src/librustc_mir/hair/pattern/check_match.rs
@@ -26,7 +26,7 @@ use std::slice;
 
 use syntax_pos::{Span, DUMMY_SP, MultiSpan};
 
-pub(crate) fn check_match<'tcx>(tcx: TyCtxt<'tcx>, def_id: DefId) {
+pub(crate) fn check_match(tcx: TyCtxt<'_>, def_id: DefId) {
     let body_id = if let Some(id) = tcx.hir().as_local_hir_id(def_id) {
         tcx.hir().body_owned_by(id)
     } else {
@@ -43,7 +43,7 @@ pub(crate) fn check_match<'tcx>(tcx: TyCtxt<'tcx>, def_id: DefId) {
     }.visit_body(tcx.hir().body(body_id));
 }
 
-fn create_e0004<'a>(sess: &'a Session, sp: Span, error_message: String) -> DiagnosticBuilder<'a> {
+fn create_e0004(sess: &Session, sp: Span, error_message: String) -> DiagnosticBuilder<'_> {
     struct_span_err!(sess, sp, E0004, "{}", &error_message)
 }
 
diff --git a/src/librustc_mir/monomorphize/collector.rs b/src/librustc_mir/monomorphize/collector.rs
index bb2738d5aa4a3..097d76925c8eb 100644
--- a/src/librustc_mir/monomorphize/collector.rs
+++ b/src/librustc_mir/monomorphize/collector.rs
@@ -281,10 +281,10 @@ impl<'tcx> InliningMap<'tcx> {
     }
 }
 
-pub fn collect_crate_mono_items<'tcx>(
-    tcx: TyCtxt<'tcx>,
+pub fn collect_crate_mono_items(
+    tcx: TyCtxt<'_>,
     mode: MonoItemCollectionMode,
-) -> (FxHashSet<MonoItem<'tcx>>, InliningMap<'tcx>) {
+) -> (FxHashSet<MonoItem<'_>>, InliningMap<'_>) {
     let roots = time(tcx.sess, "collecting roots", || {
         collect_roots(tcx, mode)
     });
@@ -315,7 +315,7 @@ pub fn collect_crate_mono_items<'tcx>(
 
 // Find all non-generic items by walking the HIR. These items serve as roots to
 // start monomorphizing from.
-fn collect_roots<'tcx>(tcx: TyCtxt<'tcx>, mode: MonoItemCollectionMode) -> Vec<MonoItem<'tcx>> {
+fn collect_roots(tcx: TyCtxt<'_>, mode: MonoItemCollectionMode) -> Vec<MonoItem<'_>> {
     debug!("Collecting roots");
     let mut roots = Vec::new();
 
@@ -912,7 +912,7 @@ fn find_vtable_types_for_unsizing<'tcx>(
     }
 }
 
-fn create_fn_mono_item<'tcx>(instance: Instance<'tcx>) -> MonoItem<'tcx> {
+fn create_fn_mono_item(instance: Instance<'_>) -> MonoItem<'_> {
     debug!("create_fn_mono_item(instance={})", instance);
     MonoItem::Fn(instance)
 }
@@ -1114,7 +1114,7 @@ impl RootCollector<'_, 'v> {
     }
 }
 
-fn item_requires_monomorphization<'tcx>(tcx: TyCtxt<'tcx>, def_id: DefId) -> bool {
+fn item_requires_monomorphization(tcx: TyCtxt<'_>, def_id: DefId) -> bool {
     let generics = tcx.generics_of(def_id);
     generics.requires_monomorphization(tcx)
 }
@@ -1243,7 +1243,7 @@ fn collect_neighbours<'tcx>(
     }
 }
 
-fn def_id_to_string<'tcx>(tcx: TyCtxt<'tcx>, def_id: DefId) -> String {
+fn def_id_to_string(tcx: TyCtxt<'_>, def_id: DefId) -> String {
     let mut output = String::new();
     let printer = DefPathBasedNames::new(tcx, false, false);
     printer.push_def_path(def_id, &mut output);
diff --git a/src/librustc_mir/monomorphize/partitioning.rs b/src/librustc_mir/monomorphize/partitioning.rs
index 32e4d4f437a78..a934c921d9257 100644
--- a/src/librustc_mir/monomorphize/partitioning.rs
+++ b/src/librustc_mir/monomorphize/partitioning.rs
@@ -839,10 +839,10 @@ where
     }
 }
 
-fn collect_and_partition_mono_items<'tcx>(
-    tcx: TyCtxt<'tcx>,
+fn collect_and_partition_mono_items(
+    tcx: TyCtxt<'_>,
     cnum: CrateNum,
-) -> (Arc<DefIdSet>, Arc<Vec<Arc<CodegenUnit<'tcx>>>>) {
+) -> (Arc<DefIdSet>, Arc<Vec<Arc<CodegenUnit<'_>>>>) {
     assert_eq!(cnum, LOCAL_CRATE);
 
     let collection_mode = match tcx.sess.opts.debugging_opts.print_mono_items {
diff --git a/src/librustc_mir/shim.rs b/src/librustc_mir/shim.rs
index 7987095a33401..32b964dbadfa9 100644
--- a/src/librustc_mir/shim.rs
+++ b/src/librustc_mir/shim.rs
@@ -829,7 +829,7 @@ fn build_call_shim<'tcx>(
     body
 }
 
-pub fn build_adt_ctor<'tcx>(tcx: TyCtxt<'tcx>, ctor_id: DefId) -> &'tcx Body<'tcx> {
+pub fn build_adt_ctor(tcx: TyCtxt<'_>, ctor_id: DefId) -> &Body<'_> {
     debug_assert!(tcx.is_constructor(ctor_id));
 
     let span = tcx.hir().span_if_local(ctor_id)
diff --git a/src/librustc_mir/transform/add_retag.rs b/src/librustc_mir/transform/add_retag.rs
index e01017d7c9bdb..de5af0a46b534 100644
--- a/src/librustc_mir/transform/add_retag.rs
+++ b/src/librustc_mir/transform/add_retag.rs
@@ -14,8 +14,8 @@ pub struct AddRetag;
 /// after the assignment, we can be sure to obtain the same place value.
 /// (Concurrent accesses by other threads are no problem as these are anyway non-atomic
 /// copies.  Data races are UB.)
-fn is_stable<'tcx>(
-    place: &Place<'tcx>,
+fn is_stable(
+    place: &Place<'_>,
 ) -> bool {
     use rustc::mir::Place::*;
 
diff --git a/src/librustc_mir/transform/check_unsafety.rs b/src/librustc_mir/transform/check_unsafety.rs
index 24df3549be481..9898ba897734d 100644
--- a/src/librustc_mir/transform/check_unsafety.rs
+++ b/src/librustc_mir/transform/check_unsafety.rs
@@ -480,11 +480,11 @@ impl<'a, 'tcx> hir::intravisit::Visitor<'tcx> for UnusedUnsafeVisitor<'a> {
     }
 }
 
-fn check_unused_unsafe<'a, 'tcx>(
-    tcx: TyCtxt<'tcx>,
+fn check_unused_unsafe(
+    tcx: TyCtxt<'_>,
     def_id: DefId,
     used_unsafe: &FxHashSet<hir::HirId>,
-    unsafe_blocks: &'a mut Vec<(hir::HirId, bool)>,
+    unsafe_blocks: &mut Vec<(hir::HirId, bool)>,
 ) {
     let body_id =
         tcx.hir().as_local_hir_id(def_id).and_then(|hir_id| {
@@ -506,7 +506,7 @@ fn check_unused_unsafe<'a, 'tcx>(
     hir::intravisit::Visitor::visit_body(&mut visitor, body);
 }
 
-fn unsafety_check_result<'tcx>(tcx: TyCtxt<'tcx>, def_id: DefId) -> UnsafetyCheckResult {
+fn unsafety_check_result(tcx: TyCtxt<'_>, def_id: DefId) -> UnsafetyCheckResult {
     debug!("unsafety_violations({:?})", def_id);
 
     // N.B., this borrow is valid because all the consumers of
@@ -545,7 +545,7 @@ fn unsafety_check_result<'tcx>(tcx: TyCtxt<'tcx>, def_id: DefId) -> UnsafetyChec
     }
 }
 
-fn unsafe_derive_on_repr_packed<'tcx>(tcx: TyCtxt<'tcx>, def_id: DefId) {
+fn unsafe_derive_on_repr_packed(tcx: TyCtxt<'_>, def_id: DefId) {
     let lint_hir_id = tcx.hir().as_local_hir_id(def_id).unwrap_or_else(||
         bug!("checking unsafety for non-local def id {:?}", def_id));
 
@@ -602,7 +602,7 @@ fn report_unused_unsafe(tcx: TyCtxt<'_>, used_unsafe: &FxHashSet<hir::HirId>, id
     db.emit();
 }
 
-fn builtin_derive_def_id<'tcx>(tcx: TyCtxt<'tcx>, def_id: DefId) -> Option<DefId> {
+fn builtin_derive_def_id(tcx: TyCtxt<'_>, def_id: DefId) -> Option<DefId> {
     debug!("builtin_derive_def_id({:?})", def_id);
     if let Some(impl_def_id) = tcx.impl_of_method(def_id) {
         if tcx.has_attr(impl_def_id, sym::automatically_derived) {
@@ -618,7 +618,7 @@ fn builtin_derive_def_id<'tcx>(tcx: TyCtxt<'tcx>, def_id: DefId) -> Option<DefId
     }
 }
 
-pub fn check_unsafety<'tcx>(tcx: TyCtxt<'tcx>, def_id: DefId) {
+pub fn check_unsafety(tcx: TyCtxt<'_>, def_id: DefId) {
     debug!("check_unsafety({:?})", def_id);
 
     // closures are handled by their parent fn.
diff --git a/src/librustc_mir/transform/dump_mir.rs b/src/librustc_mir/transform/dump_mir.rs
index 243820ba7d027..a6fb555f20bd0 100644
--- a/src/librustc_mir/transform/dump_mir.rs
+++ b/src/librustc_mir/transform/dump_mir.rs
@@ -14,7 +14,7 @@ use crate::util as mir_util;
 pub struct Marker(pub &'static str);
 
 impl MirPass for Marker {
-    fn name<'a>(&'a self) -> Cow<'a, str> {
+    fn name(&self) -> Cow<'_, str> {
         Cow::Borrowed(self.0)
     }
 
@@ -52,7 +52,7 @@ pub fn on_mir_pass<'tcx>(
     }
 }
 
-pub fn emit_mir<'tcx>(tcx: TyCtxt<'tcx>, outputs: &OutputFilenames) -> io::Result<()> {
+pub fn emit_mir(tcx: TyCtxt<'_>, outputs: &OutputFilenames) -> io::Result<()> {
     let path = outputs.path(OutputType::Mir);
     let mut f = File::create(&path)?;
     mir_util::write_mir_pretty(tcx, None, &mut f)?;
diff --git a/src/librustc_mir/transform/generator.rs b/src/librustc_mir/transform/generator.rs
index 1acebede2e41b..2ed3f7d5c26e2 100644
--- a/src/librustc_mir/transform/generator.rs
+++ b/src/librustc_mir/transform/generator.rs
@@ -1028,14 +1028,14 @@ fn create_generator_resume_function<'tcx>(
     dump_mir(tcx, None, "generator_resume", &0, source, body, |_, _| Ok(()) );
 }
 
-fn source_info<'tcx>(body: &Body<'tcx>) -> SourceInfo {
+fn source_info(body: &Body<'_>) -> SourceInfo {
     SourceInfo {
         span: body.span,
         scope: OUTERMOST_SOURCE_SCOPE,
     }
 }
 
-fn insert_clean_drop<'tcx>(body: &mut Body<'tcx>) -> BasicBlock {
+fn insert_clean_drop(body: &mut Body<'_>) -> BasicBlock {
     let return_block = insert_term_block(body, TerminatorKind::Return);
 
     // Create a block to destroy an unresumed generators. This can only destroy upvars.
diff --git a/src/librustc_mir/transform/mod.rs b/src/librustc_mir/transform/mod.rs
index 81d91dcd0a95f..7f43c4a3e89a1 100644
--- a/src/librustc_mir/transform/mod.rs
+++ b/src/librustc_mir/transform/mod.rs
@@ -50,13 +50,13 @@ pub(crate) fn provide(providers: &mut Providers<'_>) {
     };
 }
 
-fn is_mir_available<'tcx>(tcx: TyCtxt<'tcx>, def_id: DefId) -> bool {
+fn is_mir_available(tcx: TyCtxt<'_>, def_id: DefId) -> bool {
     tcx.mir_keys(def_id.krate).contains(&def_id)
 }
 
 /// Finds the full set of `DefId`s within the current crate that have
 /// MIR associated with them.
-fn mir_keys<'tcx>(tcx: TyCtxt<'tcx>, krate: CrateNum) -> &'tcx DefIdSet {
+fn mir_keys(tcx: TyCtxt<'_>, krate: CrateNum) -> &DefIdSet {
     assert_eq!(krate, LOCAL_CRATE);
 
     let mut set = DefIdSet::default();
@@ -94,7 +94,7 @@ fn mir_keys<'tcx>(tcx: TyCtxt<'tcx>, krate: CrateNum) -> &'tcx DefIdSet {
     tcx.arena.alloc(set)
 }
 
-fn mir_built<'tcx>(tcx: TyCtxt<'tcx>, def_id: DefId) -> &'tcx Steal<Body<'tcx>> {
+fn mir_built(tcx: TyCtxt<'_>, def_id: DefId) -> &Steal<Body<'_>> {
     let mir = build::mir_build(tcx, def_id);
     tcx.alloc_steal_mir(mir)
 }
@@ -137,7 +137,7 @@ pub fn default_name<T: ?Sized>() -> Cow<'static, str> {
 /// pass will be named after the type, and it will consist of a main
 /// loop that goes over each available MIR and applies `run_pass`.
 pub trait MirPass {
-    fn name<'a>(&'a self) -> Cow<'a, str> {
+    fn name(&self) -> Cow<'_, str> {
         default_name::<Self>()
     }
 
@@ -192,7 +192,7 @@ pub fn run_passes(
     }
 }
 
-fn mir_const<'tcx>(tcx: TyCtxt<'tcx>, def_id: DefId) -> &'tcx Steal<Body<'tcx>> {
+fn mir_const(tcx: TyCtxt<'_>, def_id: DefId) -> &Steal<Body<'_>> {
     // Unsafety check uses the raw mir, so make sure it is run
     let _ = tcx.unsafety_check_result(def_id);
 
@@ -223,7 +223,7 @@ fn mir_validated(tcx: TyCtxt<'tcx>, def_id: DefId) -> &'tcx Steal<Body<'tcx>> {
     tcx.alloc_steal_mir(body)
 }
 
-fn optimized_mir<'tcx>(tcx: TyCtxt<'tcx>, def_id: DefId) -> &'tcx Body<'tcx> {
+fn optimized_mir(tcx: TyCtxt<'_>, def_id: DefId) -> &Body<'_> {
     if tcx.is_constructor(def_id) {
         // There's no reason to run all of the MIR passes on constructors when
         // we can just output the MIR we want directly. This also saves const
diff --git a/src/librustc_mir/transform/qualify_consts.rs b/src/librustc_mir/transform/qualify_consts.rs
index f082b5e5a046c..3e52d3ee9bbdf 100644
--- a/src/librustc_mir/transform/qualify_consts.rs
+++ b/src/librustc_mir/transform/qualify_consts.rs
@@ -1473,7 +1473,7 @@ pub fn provide(providers: &mut Providers<'_>) {
     };
 }
 
-fn mir_const_qualif<'tcx>(tcx: TyCtxt<'tcx>, def_id: DefId) -> (u8, &'tcx BitSet<Local>) {
+fn mir_const_qualif(tcx: TyCtxt<'_>, def_id: DefId) -> (u8, &BitSet<Local>) {
     // N.B., this `borrow()` is guaranteed to be valid (i.e., the value
     // cannot yet be stolen), because `mir_validated()`, which steals
     // from `mir_const(), forces this query to execute before
diff --git a/src/librustc_mir/transform/simplify.rs b/src/librustc_mir/transform/simplify.rs
index f226f15c0096f..2eed9d453f233 100644
--- a/src/librustc_mir/transform/simplify.rs
+++ b/src/librustc_mir/transform/simplify.rs
@@ -53,7 +53,7 @@ pub fn simplify_cfg(body: &mut Body<'_>) {
 }
 
 impl MirPass for SimplifyCfg {
-    fn name<'a>(&'a self) -> Cow<'a, str> {
+    fn name(&self) -> Cow<'_, str> {
         Cow::Borrowed(&self.label)
     }
 
diff --git a/src/librustc_mir/transform/simplify_branches.rs b/src/librustc_mir/transform/simplify_branches.rs
index 0c63a8d9c96b1..f39c71ef42d71 100644
--- a/src/librustc_mir/transform/simplify_branches.rs
+++ b/src/librustc_mir/transform/simplify_branches.rs
@@ -15,7 +15,7 @@ impl SimplifyBranches {
 }
 
 impl MirPass for SimplifyBranches {
-    fn name<'a>(&'a self) -> Cow<'a, str> {
+    fn name(&self) -> Cow<'_, str> {
         Cow::Borrowed(&self.label)
     }
 
diff --git a/src/librustc_mir/util/graphviz.rs b/src/librustc_mir/util/graphviz.rs
index 1d876d7bddb53..9d142d9b700b6 100644
--- a/src/librustc_mir/util/graphviz.rs
+++ b/src/librustc_mir/util/graphviz.rs
@@ -8,8 +8,8 @@ use std::io::{self, Write};
 use super::pretty::dump_mir_def_ids;
 
 /// Write a graphviz DOT graph of a list of MIRs.
-pub fn write_mir_graphviz<'tcx, W>(
-    tcx: TyCtxt<'tcx>,
+pub fn write_mir_graphviz<W>(
+    tcx: TyCtxt<'_>,
     single: Option<DefId>,
     w: &mut W,
 ) -> io::Result<()>
diff --git a/src/librustc_mir/util/liveness.rs b/src/librustc_mir/util/liveness.rs
index 8ead571d9664d..b42eebc7ee3be 100644
--- a/src/librustc_mir/util/liveness.rs
+++ b/src/librustc_mir/util/liveness.rs
@@ -56,8 +56,8 @@ pub struct LivenessResult {
 
 /// Computes which local variables are live within the given function
 /// `mir`, including drops.
-pub fn liveness_of_locals<'tcx>(
-    body: &Body<'tcx>,
+pub fn liveness_of_locals(
+    body: &Body<'_>,
 ) -> LivenessResult {
     let num_live_vars = body.local_decls.len();
 
@@ -243,8 +243,8 @@ impl<'tcx> Visitor<'tcx> for DefsUsesVisitor
     }
 }
 
-fn block<'tcx>(
-    b: &BasicBlockData<'tcx>,
+fn block(
+    b: &BasicBlockData<'_>,
     locals: usize,
 ) -> DefsUses {
     let mut visitor = DefsUsesVisitor {
diff --git a/src/librustc_mir/util/mod.rs b/src/librustc_mir/util/mod.rs
index 719029dbaac77..fd2a5e452ce4b 100644
--- a/src/librustc_mir/util/mod.rs
+++ b/src/librustc_mir/util/mod.rs
@@ -21,7 +21,7 @@ pub use self::graphviz::{graphviz_safe_def_name, write_mir_graphviz};
 pub use self::graphviz::write_node_label as write_graphviz_node_label;
 
 /// If possible, suggest replacing `ref` with `ref mut`.
-pub fn suggest_ref_mut<'tcx>(tcx: TyCtxt<'tcx>, binding_span: Span) -> Option<(String)> {
+pub fn suggest_ref_mut(tcx: TyCtxt<'_>, binding_span: Span) -> Option<(String)> {
     let hi_src = tcx.sess.source_map().span_to_snippet(binding_span).unwrap();
     if hi_src.starts_with("ref")
         && hi_src["ref".len()..].starts_with(Pattern_White_Space)
diff --git a/src/librustc_passes/hir_stats.rs b/src/librustc_passes/hir_stats.rs
index 6936aedb9de80..e7f6abc410a32 100644
--- a/src/librustc_passes/hir_stats.rs
+++ b/src/librustc_passes/hir_stats.rs
@@ -38,7 +38,7 @@ pub fn print_hir_stats(krate: &hir::Crate) {
     collector.print("HIR STATS");
 }
 
-pub fn print_ast_stats<'v>(krate: &'v ast::Crate, title: &str) {
+pub fn print_ast_stats(krate: &ast::Crate, title: &str) {
     let mut collector = StatCollector {
         krate: None,
         data: FxHashMap::default(),
diff --git a/src/librustc_passes/layout_test.rs b/src/librustc_passes/layout_test.rs
index 8f790d1328572..6b1ce578240e4 100644
--- a/src/librustc_passes/layout_test.rs
+++ b/src/librustc_passes/layout_test.rs
@@ -14,7 +14,7 @@ use rustc::ty::TyCtxt;
 use syntax::ast::Attribute;
 use syntax::symbol::sym;
 
-pub fn test_layout<'tcx>(tcx: TyCtxt<'tcx>) {
+pub fn test_layout(tcx: TyCtxt<'_>) {
     if tcx.features().rustc_attrs {
         // if the `rustc_attrs` feature is not enabled, don't bother testing layout
         tcx.hir()
diff --git a/src/librustc_passes/loops.rs b/src/librustc_passes/loops.rs
index ed0a78b465276..616e6974110e6 100644
--- a/src/librustc_passes/loops.rs
+++ b/src/librustc_passes/loops.rs
@@ -45,7 +45,7 @@ struct CheckLoopVisitor<'a, 'hir> {
     cx: Context,
 }
 
-fn check_mod_loops<'tcx>(tcx: TyCtxt<'tcx>, module_def_id: DefId) {
+fn check_mod_loops(tcx: TyCtxt<'_>, module_def_id: DefId) {
     tcx.hir().visit_item_likes_in_module(module_def_id, &mut CheckLoopVisitor {
         sess: &tcx.sess,
         hir_map: &tcx.hir(),
diff --git a/src/librustc_passes/rvalue_promotion.rs b/src/librustc_passes/rvalue_promotion.rs
index bc1151974bb70..e14fa07fbbfe4 100644
--- a/src/librustc_passes/rvalue_promotion.rs
+++ b/src/librustc_passes/rvalue_promotion.rs
@@ -39,7 +39,7 @@ pub fn provide(providers: &mut Providers<'_>) {
     };
 }
 
-fn const_is_rvalue_promotable_to_static<'tcx>(tcx: TyCtxt<'tcx>, def_id: DefId) -> bool {
+fn const_is_rvalue_promotable_to_static(tcx: TyCtxt<'_>, def_id: DefId) -> bool {
     assert!(def_id.is_local());
 
     let hir_id = tcx.hir().as_local_hir_id(def_id)
@@ -48,7 +48,7 @@ fn const_is_rvalue_promotable_to_static<'tcx>(tcx: TyCtxt<'tcx>, def_id: DefId)
     tcx.rvalue_promotable_map(def_id).contains(&body_id.hir_id.local_id)
 }
 
-fn rvalue_promotable_map<'tcx>(tcx: TyCtxt<'tcx>, def_id: DefId) -> &'tcx ItemLocalSet {
+fn rvalue_promotable_map(tcx: TyCtxt<'_>, def_id: DefId) -> &ItemLocalSet {
     let outer_def_id = tcx.closure_base_def_id(def_id);
     if outer_def_id != def_id {
         return tcx.rvalue_promotable_map(outer_def_id);
diff --git a/src/librustc_plugin/build.rs b/src/librustc_plugin/build.rs
index d3ac597160fd6..816e283a10460 100644
--- a/src/librustc_plugin/build.rs
+++ b/src/librustc_plugin/build.rs
@@ -30,11 +30,11 @@ impl<'v> ItemLikeVisitor<'v> for RegistrarFinder {
 }
 
 /// Finds the function marked with `#[plugin_registrar]`, if any.
-pub fn find_plugin_registrar<'tcx>(tcx: TyCtxt<'tcx>) -> Option<DefId> {
+pub fn find_plugin_registrar(tcx: TyCtxt<'_>) -> Option<DefId> {
     tcx.plugin_registrar_fn(LOCAL_CRATE)
 }
 
-fn plugin_registrar_fn<'tcx>(tcx: TyCtxt<'tcx>, cnum: CrateNum) -> Option<DefId> {
+fn plugin_registrar_fn(tcx: TyCtxt<'_>, cnum: CrateNum) -> Option<DefId> {
     assert_eq!(cnum, LOCAL_CRATE);
 
     let mut finder = RegistrarFinder { registrars: Vec::new() };
diff --git a/src/librustc_plugin/registry.rs b/src/librustc_plugin/registry.rs
index 16d484e2a98f2..2fb65a6069372 100644
--- a/src/librustc_plugin/registry.rs
+++ b/src/librustc_plugin/registry.rs
@@ -77,7 +77,7 @@ impl<'a> Registry<'a> {
     ///
     /// Returns empty slice in case the plugin was loaded
     /// with `--extra-plugins`
-    pub fn args<'b>(&'b self) -> &'b [ast::NestedMetaItem] {
+    pub fn args(&self) -> &[ast::NestedMetaItem] {
         self.args_hidden.as_ref().map(|v| &v[..]).unwrap_or(&[])
     }
 
diff --git a/src/librustc_privacy/lib.rs b/src/librustc_privacy/lib.rs
index 3e98200e53274..339021f511afd 100644
--- a/src/librustc_privacy/lib.rs
+++ b/src/librustc_privacy/lib.rs
@@ -337,7 +337,7 @@ fn item_tables<'a, 'tcx>(
     if tcx.has_typeck_tables(def_id) { tcx.typeck_tables_of(def_id) } else { empty_tables }
 }
 
-fn min<'tcx>(vis1: ty::Visibility, vis2: ty::Visibility, tcx: TyCtxt<'tcx>) -> ty::Visibility {
+fn min(vis1: ty::Visibility, vis2: ty::Visibility, tcx: TyCtxt<'_>) -> ty::Visibility {
     if vis1.is_at_least(vis2, tcx) { vis2 } else { vis1 }
 }
 
@@ -384,14 +384,14 @@ impl<'a, 'tcx, VL: VisibilityLike> DefIdVisitor<'tcx> for FindMin<'a, 'tcx, VL>
 trait VisibilityLike: Sized {
     const MAX: Self;
     const SHALLOW: bool = false;
-    fn new_min<'a, 'tcx>(find: &FindMin<'a, 'tcx, Self>, def_id: DefId) -> Self;
+    fn new_min(find: &FindMin<'_, '_, Self>, def_id: DefId) -> Self;
 
     // Returns an over-approximation (`skip_assoc_tys` = true) of visibility due to
     // associated types for which we can't determine visibility precisely.
-    fn of_impl<'a, 'tcx>(
+    fn of_impl(
         hir_id: hir::HirId,
-        tcx: TyCtxt<'tcx>,
-        access_levels: &'a AccessLevels,
+        tcx: TyCtxt<'_>,
+        access_levels: &AccessLevels,
     ) -> Self {
         let mut find = FindMin { tcx, access_levels, min: Self::MAX };
         let def_id = tcx.hir().local_def_id_from_hir_id(hir_id);
@@ -404,7 +404,7 @@ trait VisibilityLike: Sized {
 }
 impl VisibilityLike for ty::Visibility {
     const MAX: Self = ty::Visibility::Public;
-    fn new_min<'a, 'tcx>(find: &FindMin<'a, 'tcx, Self>, def_id: DefId) -> Self {
+    fn new_min(find: &FindMin<'_, '_, Self>, def_id: DefId) -> Self {
         min(def_id_visibility(find.tcx, def_id).0, find.min, find.tcx)
     }
 }
@@ -420,7 +420,7 @@ impl VisibilityLike for Option<AccessLevel> {
     // both "shallow" version of its self type and "shallow" version of its trait if it exists
     // (which require reaching the `DefId`s in them).
     const SHALLOW: bool = true;
-    fn new_min<'a, 'tcx>(find: &FindMin<'a, 'tcx, Self>, def_id: DefId) -> Self {
+    fn new_min(find: &FindMin<'_, '_, Self>, def_id: DefId) -> Self {
         cmp::min(if let Some(hir_id) = find.tcx.hir().as_local_hir_id(def_id) {
             find.access_levels.map.get(&hir_id).cloned()
         } else {
@@ -1828,7 +1828,7 @@ pub fn provide(providers: &mut Providers<'_>) {
     };
 }
 
-fn check_mod_privacy<'tcx>(tcx: TyCtxt<'tcx>, module_def_id: DefId) {
+fn check_mod_privacy(tcx: TyCtxt<'_>, module_def_id: DefId) {
     let empty_tables = ty::TypeckTables::empty(None);
 
     // Check privacy of names not checked in previous compilation stages.
@@ -1855,7 +1855,7 @@ fn check_mod_privacy<'tcx>(tcx: TyCtxt<'tcx>, module_def_id: DefId) {
     intravisit::walk_mod(&mut visitor, module, hir_id);
 }
 
-fn privacy_access_levels<'tcx>(tcx: TyCtxt<'tcx>, krate: CrateNum) -> &'tcx AccessLevels {
+fn privacy_access_levels(tcx: TyCtxt<'_>, krate: CrateNum) -> &AccessLevels {
     assert_eq!(krate, LOCAL_CRATE);
 
     // Build up a set of all exported items in the AST. This is a set of all
@@ -1879,7 +1879,7 @@ fn privacy_access_levels<'tcx>(tcx: TyCtxt<'tcx>, krate: CrateNum) -> &'tcx Acce
     tcx.arena.alloc(visitor.access_levels)
 }
 
-fn check_private_in_public<'tcx>(tcx: TyCtxt<'tcx>, krate: CrateNum) {
+fn check_private_in_public(tcx: TyCtxt<'_>, krate: CrateNum) {
     assert_eq!(krate, LOCAL_CRATE);
 
     let access_levels = tcx.privacy_access_levels(LOCAL_CRATE);
diff --git a/src/librustc_resolve/lib.rs b/src/librustc_resolve/lib.rs
index f4c23a023b104..77a976a54f434 100644
--- a/src/librustc_resolve/lib.rs
+++ b/src/librustc_resolve/lib.rs
@@ -198,9 +198,9 @@ enum ResolutionError<'a> {
 ///
 /// This takes the error provided, combines it with the span and any additional spans inside the
 /// error and emits it.
-fn resolve_error<'sess, 'a>(resolver: &'sess Resolver<'_>,
-                            span: Span,
-                            resolution_error: ResolutionError<'a>) {
+fn resolve_error(resolver: &Resolver<'_>,
+                 span: Span,
+                 resolution_error: ResolutionError<'_>) {
     resolve_struct_error(resolver, span, resolution_error).emit();
 }
 
diff --git a/src/librustc_traits/chalk_context/program_clauses/primitive.rs b/src/librustc_traits/chalk_context/program_clauses/primitive.rs
index 8e4b9da6de268..6e8eed0f90725 100644
--- a/src/librustc_traits/chalk_context/program_clauses/primitive.rs
+++ b/src/librustc_traits/chalk_context/program_clauses/primitive.rs
@@ -15,7 +15,7 @@ use crate::lowering::Lower;
 use crate::generic_types;
 use std::iter;
 
-crate fn wf_clause_for_raw_ptr<'tcx>(tcx: TyCtxt<'tcx>, mutbl: hir::Mutability) -> Clauses<'tcx> {
+crate fn wf_clause_for_raw_ptr(tcx: TyCtxt<'_>, mutbl: hir::Mutability) -> Clauses<'_> {
     let ptr_ty = generic_types::raw_ptr(tcx, mutbl);
 
     let wf_clause = ProgramClause {
@@ -29,13 +29,13 @@ crate fn wf_clause_for_raw_ptr<'tcx>(tcx: TyCtxt<'tcx>, mutbl: hir::Mutability)
     tcx.mk_clauses(iter::once(wf_clause))
 }
 
-crate fn wf_clause_for_fn_ptr<'tcx>(
-    tcx: TyCtxt<'tcx>,
+crate fn wf_clause_for_fn_ptr(
+    tcx: TyCtxt<'_>,
     arity_and_output: usize,
     variadic: bool,
     unsafety: hir::Unsafety,
     abi: abi::Abi,
-) -> Clauses<'tcx> {
+) -> Clauses<'_> {
     let fn_ptr = generic_types::fn_ptr(tcx, arity_and_output, variadic, unsafety, abi);
 
     let wf_clause = ProgramClause {
@@ -50,7 +50,7 @@ crate fn wf_clause_for_fn_ptr<'tcx>(
     tcx.mk_clauses(iter::once(wf_clause))
 }
 
-crate fn wf_clause_for_slice<'tcx>(tcx: TyCtxt<'tcx>) -> Clauses<'tcx> {
+crate fn wf_clause_for_slice(tcx: TyCtxt<'_>) -> Clauses<'_> {
     let ty = generic_types::bound(tcx, 0);
     let slice_ty = tcx.mk_slice(ty);
 
@@ -111,7 +111,7 @@ crate fn wf_clause_for_array<'tcx>(
     tcx.mk_clauses(iter::once(wf_clause))
 }
 
-crate fn wf_clause_for_tuple<'tcx>(tcx: TyCtxt<'tcx>, arity: usize) -> Clauses<'tcx> {
+crate fn wf_clause_for_tuple(tcx: TyCtxt<'_>, arity: usize) -> Clauses<'_> {
     let type_list = generic_types::type_list(tcx, arity);
     let tuple_ty = tcx.mk_ty(ty::Tuple(type_list));
 
@@ -152,7 +152,7 @@ crate fn wf_clause_for_tuple<'tcx>(tcx: TyCtxt<'tcx>, arity: usize) -> Clauses<'
     tcx.mk_clauses(iter::once(wf_clause))
 }
 
-crate fn wf_clause_for_ref<'tcx>(tcx: TyCtxt<'tcx>, mutbl: hir::Mutability) -> Clauses<'tcx> {
+crate fn wf_clause_for_ref(tcx: TyCtxt<'_>, mutbl: hir::Mutability) -> Clauses<'_> {
     let region = tcx.mk_region(
         ty::ReLateBound(ty::INNERMOST, ty::BoundRegion::BrAnon(0))
     );
@@ -176,7 +176,7 @@ crate fn wf_clause_for_ref<'tcx>(tcx: TyCtxt<'tcx>, mutbl: hir::Mutability) -> C
     tcx.mk_clauses(iter::once(wf_clause))
 }
 
-crate fn wf_clause_for_fn_def<'tcx>(tcx: TyCtxt<'tcx>, def_id: DefId) -> Clauses<'tcx> {
+crate fn wf_clause_for_fn_def(tcx: TyCtxt<'_>, def_id: DefId) -> Clauses<'_> {
     let fn_def = generic_types::fn_def(tcx, def_id);
 
     let wf_clause = ProgramClause {
diff --git a/src/librustc_traits/dropck_outlives.rs b/src/librustc_traits/dropck_outlives.rs
index 3abd7e90cf10f..ecd888b606981 100644
--- a/src/librustc_traits/dropck_outlives.rs
+++ b/src/librustc_traits/dropck_outlives.rs
@@ -279,10 +279,10 @@ fn dtorck_constraint_for_ty<'tcx>(
 }
 
 /// Calculates the dtorck constraint for a type.
-crate fn adt_dtorck_constraint<'tcx>(
-    tcx: TyCtxt<'tcx>,
+crate fn adt_dtorck_constraint(
+    tcx: TyCtxt<'_>,
     def_id: DefId,
-) -> Result<DtorckConstraint<'tcx>, NoSolution> {
+) -> Result<DtorckConstraint<'_>, NoSolution> {
     let def = tcx.adt_def(def_id);
     let span = tcx.def_span(def_id);
     debug!("dtorck_constraint: {:?}", def);
@@ -313,7 +313,7 @@ crate fn adt_dtorck_constraint<'tcx>(
     Ok(result)
 }
 
-fn dedup_dtorck_constraint<'tcx>(c: &mut DtorckConstraint<'tcx>) {
+fn dedup_dtorck_constraint(c: &mut DtorckConstraint<'_>) {
     let mut outlives = FxHashSet::default();
     let mut dtorck_types = FxHashSet::default();
 
diff --git a/src/librustc_traits/lowering/environment.rs b/src/librustc_traits/lowering/environment.rs
index 0173685583148..9ff685bb4ee8a 100644
--- a/src/librustc_traits/lowering/environment.rs
+++ b/src/librustc_traits/lowering/environment.rs
@@ -160,7 +160,7 @@ crate fn program_clauses_for_env<'tcx>(
     );
 }
 
-crate fn environment<'tcx>(tcx: TyCtxt<'tcx>, def_id: DefId) -> Environment<'tcx> {
+crate fn environment(tcx: TyCtxt<'_>, def_id: DefId) -> Environment<'_> {
     use super::{Lower, IntoFromEnvGoal};
     use rustc::hir::{Node, TraitItemKind, ImplItemKind, ItemKind, ForeignItemKind};
 
diff --git a/src/librustc_traits/lowering/mod.rs b/src/librustc_traits/lowering/mod.rs
index 2a6613101614d..b0d9134c834d6 100644
--- a/src/librustc_traits/lowering/mod.rs
+++ b/src/librustc_traits/lowering/mod.rs
@@ -155,7 +155,7 @@ impl<'tcx> IntoWellFormedGoal for DomainGoal<'tcx> {
     }
 }
 
-crate fn program_clauses_for<'tcx>(tcx: TyCtxt<'tcx>, def_id: DefId) -> Clauses<'tcx> {
+crate fn program_clauses_for(tcx: TyCtxt<'_>, def_id: DefId) -> Clauses<'_> {
     // FIXME(eddyb) this should only be using `def_kind`.
     match tcx.def_key(def_id).disambiguated_data.data {
         DefPathData::TypeNs(..) => match tcx.def_kind(def_id) {
@@ -181,7 +181,7 @@ crate fn program_clauses_for<'tcx>(tcx: TyCtxt<'tcx>, def_id: DefId) -> Clauses<
     }
 }
 
-fn program_clauses_for_trait<'tcx>(tcx: TyCtxt<'tcx>, def_id: DefId) -> Clauses<'tcx> {
+fn program_clauses_for_trait(tcx: TyCtxt<'_>, def_id: DefId) -> Clauses<'_> {
     // `trait Trait<P1..Pn> where WC { .. } // P0 == Self`
 
     // Rule Implemented-From-Env (see rustc guide)
@@ -337,7 +337,7 @@ fn program_clauses_for_impl(tcx: TyCtxt<'tcx>, def_id: DefId) -> Clauses<'tcx> {
     tcx.mk_clauses(iter::once(Clause::ForAll(ty::Binder::bind(clause))))
 }
 
-pub fn program_clauses_for_type_def<'tcx>(tcx: TyCtxt<'tcx>, def_id: DefId) -> Clauses<'tcx> {
+pub fn program_clauses_for_type_def(tcx: TyCtxt<'_>, def_id: DefId) -> Clauses<'_> {
     // Rule WellFormed-Type
     //
     // `struct Ty<P1..Pn> where WC1, ..., WCm`
@@ -411,10 +411,10 @@ pub fn program_clauses_for_type_def<'tcx>(tcx: TyCtxt<'tcx>, def_id: DefId) -> C
     tcx.mk_clauses(iter::once(well_formed_clause).chain(from_env_clauses))
 }
 
-pub fn program_clauses_for_associated_type_def<'tcx>(
-    tcx: TyCtxt<'tcx>,
+pub fn program_clauses_for_associated_type_def(
+    tcx: TyCtxt<'_>,
     item_id: DefId,
-) -> Clauses<'tcx> {
+) -> Clauses<'_> {
     // Rule ProjectionEq-Placeholder
     //
     // ```
@@ -549,10 +549,10 @@ pub fn program_clauses_for_associated_type_def<'tcx>(
     tcx.mk_clauses(clauses)
 }
 
-pub fn program_clauses_for_associated_type_value<'tcx>(
-    tcx: TyCtxt<'tcx>,
+pub fn program_clauses_for_associated_type_value(
+    tcx: TyCtxt<'_>,
     item_id: DefId,
-) -> Clauses<'tcx> {
+) -> Clauses<'_> {
     // Rule Normalize-From-Impl (see rustc guide)
     //
     // ```
@@ -611,7 +611,7 @@ pub fn program_clauses_for_associated_type_value<'tcx>(
     tcx.mk_clauses(iter::once(normalize_clause))
 }
 
-pub fn dump_program_clauses<'tcx>(tcx: TyCtxt<'tcx>) {
+pub fn dump_program_clauses(tcx: TyCtxt<'_>) {
     if !tcx.features().rustc_attrs {
         return;
     }
diff --git a/src/librustc_typeck/check/dropck.rs b/src/librustc_typeck/check/dropck.rs
index a2621abf44d8d..c4c4e10a14cc0 100644
--- a/src/librustc_typeck/check/dropck.rs
+++ b/src/librustc_typeck/check/dropck.rs
@@ -29,7 +29,7 @@ use syntax_pos::Span;
 ///    struct/enum definition for the nominal type itself (i.e.
 ///    cannot do `struct S<T>; impl<T:Clone> Drop for S<T> { ... }`).
 ///
-pub fn check_drop_impl<'tcx>(tcx: TyCtxt<'tcx>, drop_impl_did: DefId) -> Result<(), ErrorReported> {
+pub fn check_drop_impl(tcx: TyCtxt<'_>, drop_impl_did: DefId) -> Result<(), ErrorReported> {
     let dtor_self_type = tcx.type_of(drop_impl_did);
     let dtor_predicates = tcx.predicates_of(drop_impl_did);
     match dtor_self_type.sty {
diff --git a/src/librustc_typeck/check/intrinsic.rs b/src/librustc_typeck/check/intrinsic.rs
index 8c2b8d1565f2f..9b1a891382209 100644
--- a/src/librustc_typeck/check/intrinsic.rs
+++ b/src/librustc_typeck/check/intrinsic.rs
@@ -79,7 +79,7 @@ pub fn intrisic_operation_unsafety(intrinsic: &str) -> hir::Unsafety {
 
 /// Remember to add all intrinsics here, in librustc_codegen_llvm/intrinsic.rs,
 /// and in libcore/intrinsics.rs
-pub fn check_intrinsic_type<'tcx>(tcx: TyCtxt<'tcx>, it: &hir::ForeignItem) {
+pub fn check_intrinsic_type(tcx: TyCtxt<'_>, it: &hir::ForeignItem) {
     let param = |n| tcx.mk_ty_param(n, InternedString::intern(&format!("P{}", n)));
     let name = it.ident.as_str();
 
@@ -385,7 +385,7 @@ pub fn check_intrinsic_type<'tcx>(tcx: TyCtxt<'tcx>, it: &hir::ForeignItem) {
 }
 
 /// Type-check `extern "platform-intrinsic" { ... }` functions.
-pub fn check_platform_intrinsic_type<'tcx>(tcx: TyCtxt<'tcx>, it: &hir::ForeignItem) {
+pub fn check_platform_intrinsic_type(tcx: TyCtxt<'_>, it: &hir::ForeignItem) {
     let param = |n| {
         let name = InternedString::intern(&format!("P{}", n));
         tcx.mk_ty_param(n, name)
diff --git a/src/librustc_typeck/check/method/suggest.rs b/src/librustc_typeck/check/method/suggest.rs
index fa1b07d2dcfcd..be00a6efe55ed 100644
--- a/src/librustc_typeck/check/method/suggest.rs
+++ b/src/librustc_typeck/check/method/suggest.rs
@@ -775,12 +775,12 @@ impl Ord for TraitInfo {
 }
 
 /// Retrieves all traits in this crate and any dependent crates.
-pub fn all_traits<'tcx>(tcx: TyCtxt<'tcx>) -> Vec<TraitInfo> {
+pub fn all_traits(tcx: TyCtxt<'_>) -> Vec<TraitInfo> {
     tcx.all_traits(LOCAL_CRATE).iter().map(|&def_id| TraitInfo { def_id }).collect()
 }
 
 /// Computes all traits in this crate and any dependent crates.
-fn compute_all_traits<'tcx>(tcx: TyCtxt<'tcx>) -> Vec<DefId> {
+fn compute_all_traits(tcx: TyCtxt<'_>) -> Vec<DefId> {
     use hir::itemlikevisit;
 
     let mut traits = vec![];
diff --git a/src/librustc_typeck/check/mod.rs b/src/librustc_typeck/check/mod.rs
index 04364874c1037..6ba65bf182488 100644
--- a/src/librustc_typeck/check/mod.rs
+++ b/src/librustc_typeck/check/mod.rs
@@ -698,31 +698,31 @@ impl ItemLikeVisitor<'tcx> for CheckItemTypesVisitor<'tcx> {
     fn visit_impl_item(&mut self, _: &'tcx hir::ImplItem) { }
 }
 
-pub fn check_wf_new<'tcx>(tcx: TyCtxt<'tcx>) {
+pub fn check_wf_new(tcx: TyCtxt<'_>) {
     let mut visit = wfcheck::CheckTypeWellFormedVisitor::new(tcx);
     tcx.hir().krate().par_visit_all_item_likes(&mut visit);
 }
 
-fn check_mod_item_types<'tcx>(tcx: TyCtxt<'tcx>, module_def_id: DefId) {
+fn check_mod_item_types(tcx: TyCtxt<'_>, module_def_id: DefId) {
     tcx.hir().visit_item_likes_in_module(module_def_id, &mut CheckItemTypesVisitor { tcx });
 }
 
-fn typeck_item_bodies<'tcx>(tcx: TyCtxt<'tcx>, crate_num: CrateNum) {
+fn typeck_item_bodies(tcx: TyCtxt<'_>, crate_num: CrateNum) {
     debug_assert!(crate_num == LOCAL_CRATE);
     tcx.par_body_owners(|body_owner_def_id| {
         tcx.ensure().typeck_tables_of(body_owner_def_id);
     });
 }
 
-fn check_item_well_formed<'tcx>(tcx: TyCtxt<'tcx>, def_id: DefId) {
+fn check_item_well_formed(tcx: TyCtxt<'_>, def_id: DefId) {
     wfcheck::check_item_well_formed(tcx, def_id);
 }
 
-fn check_trait_item_well_formed<'tcx>(tcx: TyCtxt<'tcx>, def_id: DefId) {
+fn check_trait_item_well_formed(tcx: TyCtxt<'_>, def_id: DefId) {
     wfcheck::check_trait_item(tcx, def_id);
 }
 
-fn check_impl_item_well_formed<'tcx>(tcx: TyCtxt<'tcx>, def_id: DefId) {
+fn check_impl_item_well_formed(tcx: TyCtxt<'_>, def_id: DefId) {
     wfcheck::check_impl_item(tcx, def_id);
 }
 
@@ -742,7 +742,7 @@ pub fn provide(providers: &mut Providers<'_>) {
     };
 }
 
-fn adt_destructor<'tcx>(tcx: TyCtxt<'tcx>, def_id: DefId) -> Option<ty::Destructor> {
+fn adt_destructor(tcx: TyCtxt<'_>, def_id: DefId) -> Option<ty::Destructor> {
     tcx.calculate_dtor(def_id, &mut dropck::check_drop_impl)
 }
 
@@ -755,10 +755,10 @@ fn adt_destructor<'tcx>(tcx: TyCtxt<'tcx>, def_id: DefId) -> Option<ty::Destruct
 /// may not succeed. In some cases where this function returns `None`
 /// (notably closures), `typeck_tables(def_id)` would wind up
 /// redirecting to the owning function.
-fn primary_body_of<'tcx>(
-    tcx: TyCtxt<'tcx>,
+fn primary_body_of(
+    tcx: TyCtxt<'_>,
     id: hir::HirId,
-) -> Option<(hir::BodyId, Option<&'tcx hir::FnDecl>)> {
+) -> Option<(hir::BodyId, Option<&hir::FnDecl>)> {
     match tcx.hir().get(id) {
         Node::Item(item) => {
             match item.node {
@@ -796,7 +796,7 @@ fn primary_body_of<'tcx>(
     }
 }
 
-fn has_typeck_tables<'tcx>(tcx: TyCtxt<'tcx>, def_id: DefId) -> bool {
+fn has_typeck_tables(tcx: TyCtxt<'_>, def_id: DefId) -> bool {
     // Closures' tables come from their outermost function,
     // as they are part of the same "inference environment".
     let outer_def_id = tcx.closure_base_def_id(def_id);
@@ -808,11 +808,11 @@ fn has_typeck_tables<'tcx>(tcx: TyCtxt<'tcx>, def_id: DefId) -> bool {
     primary_body_of(tcx, id).is_some()
 }
 
-fn used_trait_imports<'tcx>(tcx: TyCtxt<'tcx>, def_id: DefId) -> &'tcx DefIdSet {
+fn used_trait_imports(tcx: TyCtxt<'_>, def_id: DefId) -> &DefIdSet {
     &*tcx.typeck_tables_of(def_id).used_trait_imports
 }
 
-fn typeck_tables_of<'tcx>(tcx: TyCtxt<'tcx>, def_id: DefId) -> &'tcx ty::TypeckTables<'tcx> {
+fn typeck_tables_of(tcx: TyCtxt<'_>, def_id: DefId) -> &ty::TypeckTables<'_> {
     // Closures' tables come from their outermost function,
     // as they are part of the same "inference environment".
     let outer_def_id = tcx.closure_base_def_id(def_id);
@@ -912,7 +912,7 @@ fn typeck_tables_of<'tcx>(tcx: TyCtxt<'tcx>, def_id: DefId) -> &'tcx ty::TypeckT
     tables
 }
 
-fn check_abi<'tcx>(tcx: TyCtxt<'tcx>, span: Span, abi: Abi) {
+fn check_abi(tcx: TyCtxt<'_>, span: Span, abi: Abi) {
     if !tcx.sess.target.target.is_abi_supported(abi) {
         struct_span_err!(tcx.sess, span, E0570,
             "The ABI `{}` is not supported for the current target", abi).emit()
@@ -1285,7 +1285,7 @@ fn check_fn<'a, 'tcx>(
     (fcx, gen_ty)
 }
 
-fn check_struct<'tcx>(tcx: TyCtxt<'tcx>, id: hir::HirId, span: Span) {
+fn check_struct(tcx: TyCtxt<'_>, id: hir::HirId, span: Span) {
     let def_id = tcx.hir().local_def_id_from_hir_id(id);
     let def = tcx.adt_def(def_id);
     def.destructor(tcx); // force the destructor to be evaluated
@@ -1299,7 +1299,7 @@ fn check_struct<'tcx>(tcx: TyCtxt<'tcx>, id: hir::HirId, span: Span) {
     check_packed(tcx, span, def_id);
 }
 
-fn check_union<'tcx>(tcx: TyCtxt<'tcx>, id: hir::HirId, span: Span) {
+fn check_union(tcx: TyCtxt<'_>, id: hir::HirId, span: Span) {
     let def_id = tcx.hir().local_def_id_from_hir_id(id);
     let def = tcx.adt_def(def_id);
     def.destructor(tcx); // force the destructor to be evaluated
@@ -1461,14 +1461,14 @@ fn maybe_check_static_with_link_section(tcx: TyCtxt<'_>, id: DefId, span: Span)
     }
 }
 
-fn check_on_unimplemented<'tcx>(tcx: TyCtxt<'tcx>, trait_def_id: DefId, item: &hir::Item) {
+fn check_on_unimplemented(tcx: TyCtxt<'_>, trait_def_id: DefId, item: &hir::Item) {
     let item_def_id = tcx.hir().local_def_id_from_hir_id(item.hir_id);
     // an error would be reported if this fails.
     let _ = traits::OnUnimplementedDirective::of_item(tcx, trait_def_id, item_def_id);
 }
 
-fn report_forbidden_specialization<'tcx>(
-    tcx: TyCtxt<'tcx>,
+fn report_forbidden_specialization(
+    tcx: TyCtxt<'_>,
     impl_item: &hir::ImplItem,
     parent_impl: DefId,
 ) {
@@ -1684,7 +1684,7 @@ fn check_impl_items_against_trait<'tcx>(
 /// Checks whether a type can be represented in memory. In particular, it
 /// identifies types that contain themselves without indirection through a
 /// pointer, which would mean their size is unbounded.
-fn check_representable<'tcx>(tcx: TyCtxt<'tcx>, sp: Span, item_def_id: DefId) -> bool {
+fn check_representable(tcx: TyCtxt<'_>, sp: Span, item_def_id: DefId) -> bool {
     let rty = tcx.type_of(item_def_id);
 
     // Check that it is possible to represent this type. This call identifies
@@ -1706,7 +1706,7 @@ fn check_representable<'tcx>(tcx: TyCtxt<'tcx>, sp: Span, item_def_id: DefId) ->
     return true;
 }
 
-pub fn check_simd<'tcx>(tcx: TyCtxt<'tcx>, sp: Span, def_id: DefId) {
+pub fn check_simd(tcx: TyCtxt<'_>, sp: Span, def_id: DefId) {
     let t = tcx.type_of(def_id);
     if let ty::Adt(def, substs) = t.sty {
         if def.is_struct() {
@@ -1735,7 +1735,7 @@ pub fn check_simd<'tcx>(tcx: TyCtxt<'tcx>, sp: Span, def_id: DefId) {
     }
 }
 
-fn check_packed<'tcx>(tcx: TyCtxt<'tcx>, sp: Span, def_id: DefId) {
+fn check_packed(tcx: TyCtxt<'_>, sp: Span, def_id: DefId) {
     let repr = tcx.adt_def(def_id).repr;
     if repr.packed() {
         for attr in tcx.get_attrs(def_id).iter() {
@@ -1759,7 +1759,7 @@ fn check_packed<'tcx>(tcx: TyCtxt<'tcx>, sp: Span, def_id: DefId) {
     }
 }
 
-fn check_packed_inner<'tcx>(tcx: TyCtxt<'tcx>, def_id: DefId, stack: &mut Vec<DefId>) -> bool {
+fn check_packed_inner(tcx: TyCtxt<'_>, def_id: DefId, stack: &mut Vec<DefId>) -> bool {
     let t = tcx.type_of(def_id);
     if stack.contains(&def_id) {
         debug!("check_packed_inner: {:?} is recursive", t);
@@ -1833,7 +1833,7 @@ fn bad_non_zero_sized_fields<'tcx>(
     err.emit();
 }
 
-fn check_transparent<'tcx>(tcx: TyCtxt<'tcx>, sp: Span, def_id: DefId) {
+fn check_transparent(tcx: TyCtxt<'_>, sp: Span, def_id: DefId) {
     let adt = tcx.adt_def(def_id);
     if !adt.repr.transparent() {
         return;
@@ -1982,7 +1982,7 @@ pub fn check_enum<'tcx>(tcx: TyCtxt<'tcx>, sp: Span, vs: &'tcx [hir::Variant], i
     check_transparent(tcx, sp, def_id);
 }
 
-fn report_unexpected_variant_res<'tcx>(tcx: TyCtxt<'tcx>, res: Res, span: Span, qpath: &QPath) {
+fn report_unexpected_variant_res(tcx: TyCtxt<'_>, res: Res, span: Span, qpath: &QPath) {
     span_err!(tcx.sess, span, E0533,
               "expected unit struct/variant or constant, found {} `{}`",
               res.descr(),
diff --git a/src/librustc_typeck/check/wfcheck.rs b/src/librustc_typeck/check/wfcheck.rs
index d612d042f7f23..2c48bd8b4f026 100644
--- a/src/librustc_typeck/check/wfcheck.rs
+++ b/src/librustc_typeck/check/wfcheck.rs
@@ -68,7 +68,7 @@ impl<'tcx> CheckWfFcxBuilder<'tcx> {
 /// We do this check as a pre-pass before checking fn bodies because if these constraints are
 /// not included it frequently leads to confusing errors in fn bodies. So it's better to check
 /// the types first.
-pub fn check_item_well_formed<'tcx>(tcx: TyCtxt<'tcx>, def_id: DefId) {
+pub fn check_item_well_formed(tcx: TyCtxt<'_>, def_id: DefId) {
     let hir_id = tcx.hir().as_local_hir_id(def_id).unwrap();
     let item = tcx.hir().expect_item(hir_id);
 
@@ -156,7 +156,7 @@ pub fn check_item_well_formed<'tcx>(tcx: TyCtxt<'tcx>, def_id: DefId) {
     }
 }
 
-pub fn check_trait_item<'tcx>(tcx: TyCtxt<'tcx>, def_id: DefId) {
+pub fn check_trait_item(tcx: TyCtxt<'_>, def_id: DefId) {
     let hir_id = tcx.hir().as_local_hir_id(def_id).unwrap();
     let trait_item = tcx.hir().expect_trait_item(hir_id);
 
@@ -167,7 +167,7 @@ pub fn check_trait_item<'tcx>(tcx: TyCtxt<'tcx>, def_id: DefId) {
     check_associated_item(tcx, trait_item.hir_id, trait_item.span, method_sig);
 }
 
-pub fn check_impl_item<'tcx>(tcx: TyCtxt<'tcx>, def_id: DefId) {
+pub fn check_impl_item(tcx: TyCtxt<'_>, def_id: DefId) {
     let hir_id = tcx.hir().as_local_hir_id(def_id).unwrap();
     let impl_item = tcx.hir().expect_impl_item(hir_id);
 
@@ -178,8 +178,8 @@ pub fn check_impl_item<'tcx>(tcx: TyCtxt<'tcx>, def_id: DefId) {
     check_associated_item(tcx, impl_item.hir_id, impl_item.span, method_sig);
 }
 
-fn check_associated_item<'tcx>(
-    tcx: TyCtxt<'tcx>,
+fn check_associated_item(
+    tcx: TyCtxt<'_>,
     item_id: hir::HirId,
     span: Span,
     sig_if_method: Option<&hir::MethodSig>,
@@ -231,7 +231,7 @@ fn for_item<'tcx>(tcx: TyCtxt<'tcx>, item: &hir::Item) -> CheckWfFcxBuilder<'tcx
     for_id(tcx, item.hir_id, item.span)
 }
 
-fn for_id<'tcx>(tcx: TyCtxt<'tcx>, id: hir::HirId, span: Span) -> CheckWfFcxBuilder<'tcx> {
+fn for_id(tcx: TyCtxt<'_>, id: hir::HirId, span: Span) -> CheckWfFcxBuilder<'_> {
     let def_id = tcx.hir().local_def_id_from_hir_id(id);
     CheckWfFcxBuilder {
         inherited: Inherited::build(tcx, def_id),
@@ -317,7 +317,7 @@ fn check_type_defn<'tcx, F>(
     });
 }
 
-fn check_trait<'tcx>(tcx: TyCtxt<'tcx>, item: &hir::Item) {
+fn check_trait(tcx: TyCtxt<'_>, item: &hir::Item) {
     debug!("check_trait: {:?}", item.hir_id);
 
     let trait_def_id = tcx.hir().local_def_id_from_hir_id(item.hir_id);
@@ -340,7 +340,7 @@ fn check_trait<'tcx>(tcx: TyCtxt<'tcx>, item: &hir::Item) {
     });
 }
 
-fn check_item_fn<'tcx>(tcx: TyCtxt<'tcx>, item: &hir::Item) {
+fn check_item_fn(tcx: TyCtxt<'_>, item: &hir::Item) {
     for_item(tcx, item).with_fcx(|fcx, tcx| {
         let def_id = fcx.tcx.hir().local_def_id_from_hir_id(item.hir_id);
         let sig = fcx.tcx.fn_sig(def_id);
@@ -352,8 +352,8 @@ fn check_item_fn<'tcx>(tcx: TyCtxt<'tcx>, item: &hir::Item) {
     })
 }
 
-fn check_item_type<'tcx>(
-    tcx: TyCtxt<'tcx>,
+fn check_item_type(
+    tcx: TyCtxt<'_>,
     item_id: hir::HirId,
     ty_span: Span,
     allow_foreign_ty: bool,
@@ -980,7 +980,7 @@ fn check_variances_for_type_defn<'tcx>(
     }
 }
 
-fn report_bivariance<'tcx>(tcx: TyCtxt<'tcx>, span: Span, param_name: ast::Name) {
+fn report_bivariance(tcx: TyCtxt<'_>, span: Span, param_name: ast::Name) {
     let mut err = error_392(tcx, span, param_name);
 
     let suggested_marker_id = tcx.lang_items().phantom_data();
@@ -1023,7 +1023,7 @@ fn reject_shadowing_parameters(tcx: TyCtxt<'_>, def_id: DefId) {
 
 /// Feature gates RFC 2056 -- trivial bounds, checking for global bounds that
 /// aren't true.
-fn check_false_global_bounds<'a, 'tcx>(fcx: &FnCtxt<'a, 'tcx>, span: Span, id: hir::HirId) {
+fn check_false_global_bounds(fcx: &FnCtxt<'_, '_>, span: Span, id: hir::HirId) {
     let empty_env = ty::ParamEnv::empty();
 
     let def_id = fcx.tcx.hir().local_def_id_from_hir_id(id);
@@ -1135,11 +1135,11 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
     }
 }
 
-fn error_392<'tcx>(
-    tcx: TyCtxt<'tcx>,
+fn error_392(
+    tcx: TyCtxt<'_>,
     span: Span,
     param_name: ast::Name,
-) -> DiagnosticBuilder<'tcx> {
+) -> DiagnosticBuilder<'_> {
     let mut err = struct_span_err!(tcx.sess, span, E0392,
                   "parameter `{}` is never used", param_name);
     err.span_label(span, "unused parameter");
diff --git a/src/librustc_typeck/check_unused.rs b/src/librustc_typeck/check_unused.rs
index 7e781eeec56a9..8614de1977085 100644
--- a/src/librustc_typeck/check_unused.rs
+++ b/src/librustc_typeck/check_unused.rs
@@ -13,7 +13,7 @@ use rustc::util::nodemap::DefIdSet;
 
 use rustc_data_structures::fx::FxHashMap;
 
-pub fn check_crate<'tcx>(tcx: TyCtxt<'tcx>) {
+pub fn check_crate(tcx: TyCtxt<'_>) {
     let mut used_trait_imports = DefIdSet::default();
     for &body_id in tcx.hir().krate().bodies.keys() {
         let item_def_id = tcx.hir().body_owner_def_id(body_id);
@@ -70,7 +70,7 @@ impl CheckVisitor<'tcx> {
     }
 }
 
-fn unused_crates_lint<'tcx>(tcx: TyCtxt<'tcx>) {
+fn unused_crates_lint(tcx: TyCtxt<'_>) {
     let lint = lint::builtin::UNUSED_EXTERN_CRATES;
 
     // Collect first the crates that are completely unused.  These we
diff --git a/src/librustc_typeck/coherence/builtin.rs b/src/librustc_typeck/coherence/builtin.rs
index 42deeaf31f427..68bdcbfe3fd95 100644
--- a/src/librustc_typeck/coherence/builtin.rs
+++ b/src/librustc_typeck/coherence/builtin.rs
@@ -17,7 +17,7 @@ use rustc::hir::def_id::DefId;
 use hir::Node;
 use rustc::hir::{self, ItemKind};
 
-pub fn check_trait<'tcx>(tcx: TyCtxt<'tcx>, trait_def_id: DefId) {
+pub fn check_trait(tcx: TyCtxt<'_>, trait_def_id: DefId) {
     Checker { tcx, trait_def_id }
         .check(tcx.lang_items().drop_trait(), visit_implementation_of_drop)
         .check(tcx.lang_items().copy_trait(), visit_implementation_of_copy)
@@ -46,7 +46,7 @@ impl<'tcx> Checker<'tcx> {
     }
 }
 
-fn visit_implementation_of_drop<'tcx>(tcx: TyCtxt<'tcx>, impl_did: DefId) {
+fn visit_implementation_of_drop(tcx: TyCtxt<'_>, impl_did: DefId) {
     if let ty::Adt(..) = tcx.type_of(impl_did).sty {
         /* do nothing */
     } else {
@@ -74,7 +74,7 @@ fn visit_implementation_of_drop<'tcx>(tcx: TyCtxt<'tcx>, impl_did: DefId) {
     }
 }
 
-fn visit_implementation_of_copy<'tcx>(tcx: TyCtxt<'tcx>, impl_did: DefId) {
+fn visit_implementation_of_copy(tcx: TyCtxt<'_>, impl_did: DefId) {
     debug!("visit_implementation_of_copy: impl_did={:?}", impl_did);
 
     let impl_hir_id = if let Some(n) = tcx.hir().as_local_hir_id(impl_did) {
@@ -154,7 +154,7 @@ fn visit_implementation_of_coerce_unsized(tcx: TyCtxt<'tcx>, impl_did: DefId) {
     }
 }
 
-fn visit_implementation_of_dispatch_from_dyn<'tcx>(tcx: TyCtxt<'tcx>, impl_did: DefId) {
+fn visit_implementation_of_dispatch_from_dyn(tcx: TyCtxt<'_>, impl_did: DefId) {
     debug!("visit_implementation_of_dispatch_from_dyn: impl_did={:?}",
            impl_did);
     if impl_did.is_local() {
diff --git a/src/librustc_typeck/coherence/inherent_impls.rs b/src/librustc_typeck/coherence/inherent_impls.rs
index 6088c03fc0681..f208c6a138d26 100644
--- a/src/librustc_typeck/coherence/inherent_impls.rs
+++ b/src/librustc_typeck/coherence/inherent_impls.rs
@@ -17,10 +17,10 @@ use syntax::ast;
 use syntax_pos::Span;
 
 /// On-demand query: yields a map containing all types mapped to their inherent impls.
-pub fn crate_inherent_impls<'tcx>(
-    tcx: TyCtxt<'tcx>,
+pub fn crate_inherent_impls(
+    tcx: TyCtxt<'_>,
     crate_num: CrateNum,
-) -> &'tcx CrateInherentImpls {
+) -> &CrateInherentImpls {
     assert_eq!(crate_num, LOCAL_CRATE);
 
     let krate = tcx.hir().krate();
@@ -33,7 +33,7 @@ pub fn crate_inherent_impls<'tcx>(
 }
 
 /// On-demand query: yields a vector of the inherent impls for a specific type.
-pub fn inherent_impls<'tcx>(tcx: TyCtxt<'tcx>, ty_def_id: DefId) -> &'tcx [DefId] {
+pub fn inherent_impls(tcx: TyCtxt<'_>, ty_def_id: DefId) -> &[DefId] {
     assert!(ty_def_id.is_local());
 
     // NB. Until we adopt the red-green dep-tracking algorithm (see
diff --git a/src/librustc_typeck/coherence/inherent_impls_overlap.rs b/src/librustc_typeck/coherence/inherent_impls_overlap.rs
index aae1b1777a30f..1785304fb1d48 100644
--- a/src/librustc_typeck/coherence/inherent_impls_overlap.rs
+++ b/src/librustc_typeck/coherence/inherent_impls_overlap.rs
@@ -5,7 +5,7 @@ use rustc::hir::itemlikevisit::ItemLikeVisitor;
 use rustc::traits::{self, IntercrateMode};
 use rustc::ty::TyCtxt;
 
-pub fn crate_inherent_impls_overlap_check<'tcx>(tcx: TyCtxt<'tcx>, crate_num: CrateNum) {
+pub fn crate_inherent_impls_overlap_check(tcx: TyCtxt<'_>, crate_num: CrateNum) {
     assert_eq!(crate_num, LOCAL_CRATE);
     let krate = tcx.hir().krate();
     krate.visit_all_item_likes(&mut InherentOverlapChecker { tcx });
diff --git a/src/librustc_typeck/coherence/mod.rs b/src/librustc_typeck/coherence/mod.rs
index 4336e861ce216..9b9789139b70f 100644
--- a/src/librustc_typeck/coherence/mod.rs
+++ b/src/librustc_typeck/coherence/mod.rs
@@ -18,7 +18,7 @@ mod inherent_impls_overlap;
 mod orphan;
 mod unsafety;
 
-fn check_impl<'tcx>(tcx: TyCtxt<'tcx>, hir_id: HirId) {
+fn check_impl(tcx: TyCtxt<'_>, hir_id: HirId) {
     let impl_def_id = tcx.hir().local_def_id_from_hir_id(hir_id);
 
     // If there are no traits, then this implementation must have a
@@ -124,7 +124,7 @@ pub fn provide(providers: &mut Providers<'_>) {
     };
 }
 
-fn coherent_trait<'tcx>(tcx: TyCtxt<'tcx>, def_id: DefId) {
+fn coherent_trait(tcx: TyCtxt<'_>, def_id: DefId) {
     let impls = tcx.hir().trait_impls(def_id);
     for &impl_id in impls {
         check_impl(tcx, impl_id);
@@ -135,7 +135,7 @@ fn coherent_trait<'tcx>(tcx: TyCtxt<'tcx>, def_id: DefId) {
     builtin::check_trait(tcx, def_id);
 }
 
-pub fn check_coherence<'tcx>(tcx: TyCtxt<'tcx>) {
+pub fn check_coherence(tcx: TyCtxt<'_>) {
     for &trait_def_id in tcx.hir().krate().trait_impls.keys() {
         tcx.ensure().coherent_trait(trait_def_id);
     }
@@ -151,7 +151,7 @@ pub fn check_coherence<'tcx>(tcx: TyCtxt<'tcx>) {
 /// Overlap: no two impls for the same trait are implemented for the
 /// same type. Likewise, no two inherent impls for a given type
 /// constructor provide a method with the same name.
-fn check_impl_overlap<'tcx>(tcx: TyCtxt<'tcx>, hir_id: HirId) {
+fn check_impl_overlap(tcx: TyCtxt<'_>, hir_id: HirId) {
     let impl_def_id = tcx.hir().local_def_id_from_hir_id(hir_id);
     let trait_ref = tcx.impl_trait_ref(impl_def_id).unwrap();
     let trait_def_id = trait_ref.def_id;
diff --git a/src/librustc_typeck/coherence/orphan.rs b/src/librustc_typeck/coherence/orphan.rs
index 4e6fcfe0593e2..2d0faecd8ee71 100644
--- a/src/librustc_typeck/coherence/orphan.rs
+++ b/src/librustc_typeck/coherence/orphan.rs
@@ -6,7 +6,7 @@ use rustc::ty::{self, TyCtxt};
 use rustc::hir::itemlikevisit::ItemLikeVisitor;
 use rustc::hir;
 
-pub fn check<'tcx>(tcx: TyCtxt<'tcx>) {
+pub fn check(tcx: TyCtxt<'_>) {
     let mut orphan = OrphanChecker { tcx };
     tcx.hir().krate().visit_all_item_likes(&mut orphan);
 }
diff --git a/src/librustc_typeck/coherence/unsafety.rs b/src/librustc_typeck/coherence/unsafety.rs
index c41a0e1514e68..123d7c6123b89 100644
--- a/src/librustc_typeck/coherence/unsafety.rs
+++ b/src/librustc_typeck/coherence/unsafety.rs
@@ -5,7 +5,7 @@ use rustc::ty::TyCtxt;
 use rustc::hir::itemlikevisit::ItemLikeVisitor;
 use rustc::hir::{self, Unsafety};
 
-pub fn check<'tcx>(tcx: TyCtxt<'tcx>) {
+pub fn check(tcx: TyCtxt<'_>) {
     let mut unsafety = UnsafetyChecker { tcx };
     tcx.hir().krate().visit_all_item_likes(&mut unsafety);
 }
diff --git a/src/librustc_typeck/collect.rs b/src/librustc_typeck/collect.rs
index 8464a710a4ae3..e5802179ec479 100644
--- a/src/librustc_typeck/collect.rs
+++ b/src/librustc_typeck/collect.rs
@@ -56,7 +56,7 @@ struct OnlySelfBounds(bool);
 ///////////////////////////////////////////////////////////////////////////
 // Main entry point
 
-fn collect_mod_item_types<'tcx>(tcx: TyCtxt<'tcx>, module_def_id: DefId) {
+fn collect_mod_item_types(tcx: TyCtxt<'_>, module_def_id: DefId) {
     tcx.hir().visit_item_likes_in_module(
         module_def_id,
         &mut CollectItemTypesVisitor { tcx }.as_deep_visitor()
@@ -253,10 +253,10 @@ impl AstConv<'tcx> for ItemCtxt<'tcx> {
     }
 }
 
-fn type_param_predicates<'tcx>(
-    tcx: TyCtxt<'tcx>,
+fn type_param_predicates(
+    tcx: TyCtxt<'_>,
     (item_def_id, def_id): (DefId, DefId),
-) -> &'tcx ty::GenericPredicates<'tcx> {
+) -> &ty::GenericPredicates<'_> {
     use rustc::hir::*;
 
     // In the AST, bounds can derive from two places. Either
@@ -381,7 +381,7 @@ impl ItemCtxt<'tcx> {
 /// parameter with ID `param_id`. We use this so as to avoid running
 /// `ast_ty_to_ty`, because we want to avoid triggering an all-out
 /// conversion of the type to avoid inducing unnecessary cycles.
-fn is_param<'tcx>(tcx: TyCtxt<'tcx>, ast_ty: &hir::Ty, param_id: hir::HirId) -> bool {
+fn is_param(tcx: TyCtxt<'_>, ast_ty: &hir::Ty, param_id: hir::HirId) -> bool {
     if let hir::TyKind::Path(hir::QPath::Resolved(None, ref path)) = ast_ty.node {
         match path.res {
             Res::SelfTy(Some(def_id), None) | Res::Def(DefKind::TyParam, def_id) => {
@@ -394,7 +394,7 @@ fn is_param<'tcx>(tcx: TyCtxt<'tcx>, ast_ty: &hir::Ty, param_id: hir::HirId) ->
     }
 }
 
-fn convert_item<'tcx>(tcx: TyCtxt<'tcx>, item_id: hir::HirId) {
+fn convert_item(tcx: TyCtxt<'_>, item_id: hir::HirId) {
     let it = tcx.hir().expect_item(item_id);
     debug!("convert: item {} with id {}", it.ident, it.hir_id);
     let def_id = tcx.hir().local_def_id_from_hir_id(item_id);
@@ -476,7 +476,7 @@ fn convert_item<'tcx>(tcx: TyCtxt<'tcx>, item_id: hir::HirId) {
     }
 }
 
-fn convert_trait_item<'tcx>(tcx: TyCtxt<'tcx>, trait_item_id: hir::HirId) {
+fn convert_trait_item(tcx: TyCtxt<'_>, trait_item_id: hir::HirId) {
     let trait_item = tcx.hir().expect_trait_item(trait_item_id);
     let def_id = tcx.hir().local_def_id_from_hir_id(trait_item.hir_id);
     tcx.generics_of(def_id);
@@ -497,7 +497,7 @@ fn convert_trait_item<'tcx>(tcx: TyCtxt<'tcx>, trait_item_id: hir::HirId) {
     tcx.predicates_of(def_id);
 }
 
-fn convert_impl_item<'tcx>(tcx: TyCtxt<'tcx>, impl_item_id: hir::HirId) {
+fn convert_impl_item(tcx: TyCtxt<'_>, impl_item_id: hir::HirId) {
     let def_id = tcx.hir().local_def_id_from_hir_id(impl_item_id);
     tcx.generics_of(def_id);
     tcx.type_of(def_id);
@@ -507,7 +507,7 @@ fn convert_impl_item<'tcx>(tcx: TyCtxt<'tcx>, impl_item_id: hir::HirId) {
     }
 }
 
-fn convert_variant_ctor<'tcx>(tcx: TyCtxt<'tcx>, ctor_id: hir::HirId) {
+fn convert_variant_ctor(tcx: TyCtxt<'_>, ctor_id: hir::HirId) {
     let def_id = tcx.hir().local_def_id_from_hir_id(ctor_id);
     tcx.generics_of(def_id);
     tcx.type_of(def_id);
@@ -562,8 +562,8 @@ fn convert_enum_variant_types<'tcx>(tcx: TyCtxt<'tcx>, def_id: DefId, variants:
     }
 }
 
-fn convert_variant<'tcx>(
-    tcx: TyCtxt<'tcx>,
+fn convert_variant(
+    tcx: TyCtxt<'_>,
     variant_did: Option<DefId>,
     ctor_did: Option<DefId>,
     ident: Ident,
@@ -619,7 +619,7 @@ fn convert_variant<'tcx>(
     )
 }
 
-fn adt_def<'tcx>(tcx: TyCtxt<'tcx>, def_id: DefId) -> &'tcx ty::AdtDef {
+fn adt_def(tcx: TyCtxt<'_>, def_id: DefId) -> &ty::AdtDef {
     use rustc::hir::*;
 
     let hir_id = tcx.hir().as_local_hir_id(def_id).unwrap();
@@ -686,10 +686,10 @@ fn adt_def<'tcx>(tcx: TyCtxt<'tcx>, def_id: DefId) -> &'tcx ty::AdtDef {
 /// Ensures that the super-predicates of the trait with a `DefId`
 /// of `trait_def_id` are converted and stored. This also ensures that
 /// the transitive super-predicates are converted.
-fn super_predicates_of<'tcx>(
-    tcx: TyCtxt<'tcx>,
+fn super_predicates_of(
+    tcx: TyCtxt<'_>,
     trait_def_id: DefId,
-) -> &'tcx ty::GenericPredicates<'tcx> {
+) -> &ty::GenericPredicates<'_> {
     debug!("super_predicates(trait_def_id={:?})", trait_def_id);
     let trait_hir_id = tcx.hir().as_local_hir_id(trait_def_id).unwrap();
 
@@ -740,7 +740,7 @@ fn super_predicates_of<'tcx>(
     })
 }
 
-fn trait_def<'tcx>(tcx: TyCtxt<'tcx>, def_id: DefId) -> &'tcx ty::TraitDef {
+fn trait_def(tcx: TyCtxt<'_>, def_id: DefId) -> &ty::TraitDef {
     let hir_id = tcx.hir().as_local_hir_id(def_id).unwrap();
     let item = tcx.hir().expect_item(hir_id);
 
@@ -879,7 +879,7 @@ fn has_late_bound_regions<'tcx>(tcx: TyCtxt<'tcx>, node: Node<'tcx>) -> Option<S
     }
 }
 
-fn generics_of<'tcx>(tcx: TyCtxt<'tcx>, def_id: DefId) -> &'tcx ty::Generics {
+fn generics_of(tcx: TyCtxt<'_>, def_id: DefId) -> &ty::Generics {
     use rustc::hir::*;
 
     let hir_id = tcx.hir().as_local_hir_id(def_id).unwrap();
@@ -1122,7 +1122,7 @@ fn generics_of<'tcx>(tcx: TyCtxt<'tcx>, def_id: DefId) -> &'tcx ty::Generics {
     })
 }
 
-fn report_assoc_ty_on_inherent_impl<'tcx>(tcx: TyCtxt<'tcx>, span: Span) {
+fn report_assoc_ty_on_inherent_impl(tcx: TyCtxt<'_>, span: Span) {
     span_err!(
         tcx.sess,
         span,
@@ -1131,7 +1131,7 @@ fn report_assoc_ty_on_inherent_impl<'tcx>(tcx: TyCtxt<'tcx>, span: Span) {
     );
 }
 
-fn type_of<'tcx>(tcx: TyCtxt<'tcx>, def_id: DefId) -> Ty<'tcx> {
+fn type_of(tcx: TyCtxt<'_>, def_id: DefId) -> Ty<'_> {
     checked_type_of(tcx, def_id, true).unwrap()
 }
 
@@ -1139,7 +1139,7 @@ fn type_of<'tcx>(tcx: TyCtxt<'tcx>, def_id: DefId) -> Ty<'tcx> {
 ///
 /// If you want to fail anyway, you can set the `fail` parameter to true, but in this case,
 /// you'd better just call [`type_of`] directly.
-pub fn checked_type_of<'tcx>(tcx: TyCtxt<'tcx>, def_id: DefId, fail: bool) -> Option<Ty<'tcx>> {
+pub fn checked_type_of(tcx: TyCtxt<'_>, def_id: DefId, fail: bool) -> Option<Ty<'_>> {
     use rustc::hir::*;
 
     let hir_id = match tcx.hir().as_local_hir_id(def_id) {
@@ -1464,7 +1464,7 @@ pub fn checked_type_of<'tcx>(tcx: TyCtxt<'tcx>, def_id: DefId, fail: bool) -> Op
     })
 }
 
-fn find_existential_constraints<'tcx>(tcx: TyCtxt<'tcx>, def_id: DefId) -> Ty<'tcx> {
+fn find_existential_constraints(tcx: TyCtxt<'_>, def_id: DefId) -> Ty<'_> {
     use rustc::hir::{ImplItem, Item, TraitItem};
 
     debug!("find_existential_constraints({:?})", def_id);
@@ -1682,7 +1682,7 @@ fn find_existential_constraints<'tcx>(tcx: TyCtxt<'tcx>, def_id: DefId) -> Ty<'t
     }
 }
 
-fn fn_sig<'tcx>(tcx: TyCtxt<'tcx>, def_id: DefId) -> ty::PolyFnSig<'tcx> {
+fn fn_sig(tcx: TyCtxt<'_>, def_id: DefId) -> ty::PolyFnSig<'_> {
     use rustc::hir::*;
     use rustc::hir::Node::*;
 
@@ -1758,7 +1758,7 @@ fn fn_sig<'tcx>(tcx: TyCtxt<'tcx>, def_id: DefId) -> ty::PolyFnSig<'tcx> {
     }
 }
 
-fn impl_trait_ref<'tcx>(tcx: TyCtxt<'tcx>, def_id: DefId) -> Option<ty::TraitRef<'tcx>> {
+fn impl_trait_ref(tcx: TyCtxt<'_>, def_id: DefId) -> Option<ty::TraitRef<'_>> {
     let icx = ItemCtxt::new(tcx, def_id);
 
     let hir_id = tcx.hir().as_local_hir_id(def_id).unwrap();
@@ -1773,7 +1773,7 @@ fn impl_trait_ref<'tcx>(tcx: TyCtxt<'tcx>, def_id: DefId) -> Option<ty::TraitRef
     }
 }
 
-fn impl_polarity<'tcx>(tcx: TyCtxt<'tcx>, def_id: DefId) -> hir::ImplPolarity {
+fn impl_polarity(tcx: TyCtxt<'_>, def_id: DefId) -> hir::ImplPolarity {
     let hir_id = tcx.hir().as_local_hir_id(def_id).unwrap();
     match tcx.hir().expect_item(hir_id).node {
         hir::ItemKind::Impl(_, polarity, ..) => polarity,
@@ -1804,10 +1804,10 @@ fn early_bound_lifetimes_from_generics<'a, 'tcx: 'a>(
 /// Returns a list of type predicates for the definition with ID `def_id`, including inferred
 /// lifetime constraints. This includes all predicates returned by `explicit_predicates_of`, plus
 /// inferred constraints concerning which regions outlive other regions.
-fn predicates_defined_on<'tcx>(
-    tcx: TyCtxt<'tcx>,
+fn predicates_defined_on(
+    tcx: TyCtxt<'_>,
     def_id: DefId,
-) -> &'tcx ty::GenericPredicates<'tcx> {
+) -> &ty::GenericPredicates<'_> {
     debug!("predicates_defined_on({:?})", def_id);
     let mut result = tcx.explicit_predicates_of(def_id);
     debug!(
@@ -1834,7 +1834,7 @@ fn predicates_defined_on<'tcx>(
 /// Returns a list of all type predicates (explicit and implicit) for the definition with
 /// ID `def_id`. This includes all predicates returned by `predicates_defined_on`, plus
 /// `Self: Trait` predicates for traits.
-fn predicates_of<'tcx>(tcx: TyCtxt<'tcx>, def_id: DefId) -> &'tcx ty::GenericPredicates<'tcx> {
+fn predicates_of(tcx: TyCtxt<'_>, def_id: DefId) -> &ty::GenericPredicates<'_> {
     let mut result = tcx.predicates_defined_on(def_id);
 
     if tcx.is_trait(def_id) {
@@ -1861,10 +1861,10 @@ fn predicates_of<'tcx>(tcx: TyCtxt<'tcx>, def_id: DefId) -> &'tcx ty::GenericPre
 
 /// Returns a list of user-specified type predicates for the definition with ID `def_id`.
 /// N.B., this does not include any implied/inferred constraints.
-fn explicit_predicates_of<'tcx>(
-    tcx: TyCtxt<'tcx>,
+fn explicit_predicates_of(
+    tcx: TyCtxt<'_>,
     def_id: DefId,
-) -> &'tcx ty::GenericPredicates<'tcx> {
+) -> &ty::GenericPredicates<'_> {
     use rustc::hir::*;
     use rustc_data_structures::fx::FxHashSet;
 
@@ -2271,7 +2271,7 @@ fn compute_sig_of_foreign_fn_decl<'tcx>(
     fty
 }
 
-fn is_foreign_item<'tcx>(tcx: TyCtxt<'tcx>, def_id: DefId) -> bool {
+fn is_foreign_item(tcx: TyCtxt<'_>, def_id: DefId) -> bool {
     match tcx.hir().get_if_local(def_id) {
         Some(Node::ForeignItem(..)) => true,
         Some(_) => false,
@@ -2279,7 +2279,7 @@ fn is_foreign_item<'tcx>(tcx: TyCtxt<'tcx>, def_id: DefId) -> bool {
     }
 }
 
-fn static_mutability<'tcx>(tcx: TyCtxt<'tcx>, def_id: DefId) -> Option<hir::Mutability> {
+fn static_mutability(tcx: TyCtxt<'_>, def_id: DefId) -> Option<hir::Mutability> {
     match tcx.hir().get_if_local(def_id) {
         Some(Node::Item(&hir::Item {
             node: hir::ItemKind::Static(_, mutbl, _), ..
@@ -2387,7 +2387,7 @@ fn from_target_feature(
     }
 }
 
-fn linkage_by_name<'tcx>(tcx: TyCtxt<'tcx>, def_id: DefId, name: &str) -> Linkage {
+fn linkage_by_name(tcx: TyCtxt<'_>, def_id: DefId, name: &str) -> Linkage {
     use rustc::mir::mono::Linkage::*;
 
     // Use the names from src/llvm/docs/LangRef.rst here. Most types are only
@@ -2422,7 +2422,7 @@ fn linkage_by_name<'tcx>(tcx: TyCtxt<'tcx>, def_id: DefId, name: &str) -> Linkag
     }
 }
 
-fn codegen_fn_attrs<'tcx>(tcx: TyCtxt<'tcx>, id: DefId) -> CodegenFnAttrs {
+fn codegen_fn_attrs(tcx: TyCtxt<'_>, id: DefId) -> CodegenFnAttrs {
     let attrs = tcx.get_attrs(id);
 
     let mut codegen_fn_attrs = CodegenFnAttrs::new();
diff --git a/src/librustc_typeck/impl_wf_check.rs b/src/librustc_typeck/impl_wf_check.rs
index b833d8555ee0a..08c7cbc389a67 100644
--- a/src/librustc_typeck/impl_wf_check.rs
+++ b/src/librustc_typeck/impl_wf_check.rs
@@ -49,7 +49,7 @@ use syntax_pos::Span;
 /// impl<'a> Trait<Foo> for Bar { type X = &'a i32; }
 /// //   ^ 'a is unused and appears in assoc type, error
 /// ```
-pub fn impl_wf_check<'tcx>(tcx: TyCtxt<'tcx>) {
+pub fn impl_wf_check(tcx: TyCtxt<'_>) {
     // We will tag this as part of the WF check -- logically, it is,
     // but it's one that we must perform earlier than the rest of
     // WfCheck.
@@ -58,7 +58,7 @@ pub fn impl_wf_check<'tcx>(tcx: TyCtxt<'tcx>) {
     }
 }
 
-fn check_mod_impl_wf<'tcx>(tcx: TyCtxt<'tcx>, module_def_id: DefId) {
+fn check_mod_impl_wf(tcx: TyCtxt<'_>, module_def_id: DefId) {
     tcx.hir().visit_item_likes_in_module(
         module_def_id,
         &mut ImplWfCheck { tcx }
@@ -92,8 +92,8 @@ impl ItemLikeVisitor<'tcx> for ImplWfCheck<'tcx> {
     fn visit_impl_item(&mut self, _impl_item: &'tcx hir::ImplItem) { }
 }
 
-fn enforce_impl_params_are_constrained<'tcx>(
-    tcx: TyCtxt<'tcx>,
+fn enforce_impl_params_are_constrained(
+    tcx: TyCtxt<'_>,
     impl_def_id: DefId,
     impl_item_refs: &[hir::ImplItemRef],
 ) {
@@ -183,7 +183,7 @@ fn report_unused_parameter(tcx: TyCtxt<'_>, span: Span, kind: &str, name: &str)
 }
 
 /// Enforce that we do not have two items in an impl with the same name.
-fn enforce_impl_items_are_distinct<'tcx>(tcx: TyCtxt<'tcx>, impl_item_refs: &[hir::ImplItemRef]) {
+fn enforce_impl_items_are_distinct(tcx: TyCtxt<'_>, impl_item_refs: &[hir::ImplItemRef]) {
     let mut seen_type_items = FxHashMap::default();
     let mut seen_value_items = FxHashMap::default();
     for impl_item_ref in impl_item_refs {
diff --git a/src/librustc_typeck/lib.rs b/src/librustc_typeck/lib.rs
index 85ae55b2dd946..56c7544eaf57a 100644
--- a/src/librustc_typeck/lib.rs
+++ b/src/librustc_typeck/lib.rs
@@ -161,7 +161,7 @@ fn require_same_types<'tcx>(
     })
 }
 
-fn check_main_fn_ty<'tcx>(tcx: TyCtxt<'tcx>, main_def_id: DefId) {
+fn check_main_fn_ty(tcx: TyCtxt<'_>, main_def_id: DefId) {
     let main_id = tcx.hir().as_local_hir_id(main_def_id).unwrap();
     let main_span = tcx.def_span(main_def_id);
     let main_t = tcx.type_of(main_def_id);
@@ -226,7 +226,7 @@ fn check_main_fn_ty<'tcx>(tcx: TyCtxt<'tcx>, main_def_id: DefId) {
     }
 }
 
-fn check_start_fn_ty<'tcx>(tcx: TyCtxt<'tcx>, start_def_id: DefId) {
+fn check_start_fn_ty(tcx: TyCtxt<'_>, start_def_id: DefId) {
     let start_id = tcx.hir().as_local_hir_id(start_def_id).unwrap();
     let start_span = tcx.def_span(start_def_id);
     let start_t = tcx.type_of(start_def_id);
@@ -283,7 +283,7 @@ fn check_start_fn_ty<'tcx>(tcx: TyCtxt<'tcx>, start_def_id: DefId) {
     }
 }
 
-fn check_for_entry_fn<'tcx>(tcx: TyCtxt<'tcx>) {
+fn check_for_entry_fn(tcx: TyCtxt<'_>) {
     match tcx.entry_fn(LOCAL_CRATE) {
         Some((def_id, EntryFnType::Main)) => check_main_fn_ty(tcx, def_id),
         Some((def_id, EntryFnType::Start)) => check_start_fn_ty(tcx, def_id),
@@ -300,7 +300,7 @@ pub fn provide(providers: &mut Providers<'_>) {
     impl_wf_check::provide(providers);
 }
 
-pub fn check_crate<'tcx>(tcx: TyCtxt<'tcx>) -> Result<(), ErrorReported> {
+pub fn check_crate(tcx: TyCtxt<'_>) -> Result<(), ErrorReported> {
     tcx.sess.profiler(|p| p.start_activity("type-check crate"));
 
     // this ensures that later parts of type checking can assume that items
diff --git a/src/librustc_typeck/outlives/mod.rs b/src/librustc_typeck/outlives/mod.rs
index 63e41e01fbff5..6b8f6fccd40d7 100644
--- a/src/librustc_typeck/outlives/mod.rs
+++ b/src/librustc_typeck/outlives/mod.rs
@@ -20,10 +20,10 @@ pub fn provide(providers: &mut Providers<'_>) {
     };
 }
 
-fn inferred_outlives_of<'tcx>(
-    tcx: TyCtxt<'tcx>,
+fn inferred_outlives_of(
+    tcx: TyCtxt<'_>,
     item_def_id: DefId,
-) -> &'tcx [ty::Predicate<'tcx>] {
+) -> &[ty::Predicate<'_>] {
     let id = tcx
         .hir()
         .as_local_hir_id(item_def_id)
@@ -70,10 +70,10 @@ fn inferred_outlives_of<'tcx>(
     }
 }
 
-fn inferred_outlives_crate<'tcx>(
-    tcx: TyCtxt<'tcx>,
+fn inferred_outlives_crate(
+    tcx: TyCtxt<'_>,
     crate_num: CrateNum,
-) -> &'tcx CratePredicatesMap<'tcx> {
+) -> &CratePredicatesMap<'_> {
     assert_eq!(crate_num, LOCAL_CRATE);
 
     // Compute a map from each struct/enum/union S to the **explicit**
diff --git a/src/librustc_typeck/outlives/test.rs b/src/librustc_typeck/outlives/test.rs
index 4690cb9eada2e..5ddf95b0f80c2 100644
--- a/src/librustc_typeck/outlives/test.rs
+++ b/src/librustc_typeck/outlives/test.rs
@@ -3,7 +3,7 @@ use rustc::hir::itemlikevisit::ItemLikeVisitor;
 use rustc::ty::TyCtxt;
 use syntax::symbol::sym;
 
-pub fn test_inferred_outlives<'tcx>(tcx: TyCtxt<'tcx>) {
+pub fn test_inferred_outlives(tcx: TyCtxt<'_>) {
     tcx.hir()
        .krate()
        .visit_all_item_likes(&mut OutlivesTest { tcx });
diff --git a/src/librustc_typeck/outlives/utils.rs b/src/librustc_typeck/outlives/utils.rs
index c6b0da3fe474c..783890da639f4 100644
--- a/src/librustc_typeck/outlives/utils.rs
+++ b/src/librustc_typeck/outlives/utils.rs
@@ -125,7 +125,7 @@ pub fn insert_outlives_predicate<'tcx>(
     }
 }
 
-fn is_free_region<'tcx>(tcx: TyCtxt<'tcx>, region: Region<'_>) -> bool {
+fn is_free_region(tcx: TyCtxt<'_>, region: Region<'_>) -> bool {
     // First, screen for regions that might appear in a type header.
     match region {
         // These correspond to `T: 'a` relationships:
diff --git a/src/librustc_typeck/variance/mod.rs b/src/librustc_typeck/variance/mod.rs
index 1a8871a3da9da..343d7ea656fbb 100644
--- a/src/librustc_typeck/variance/mod.rs
+++ b/src/librustc_typeck/variance/mod.rs
@@ -34,7 +34,7 @@ pub fn provide(providers: &mut Providers<'_>) {
     };
 }
 
-fn crate_variances<'tcx>(tcx: TyCtxt<'tcx>, crate_num: CrateNum) -> &'tcx CrateVariancesMap<'tcx> {
+fn crate_variances(tcx: TyCtxt<'_>, crate_num: CrateNum) -> &CrateVariancesMap<'_> {
     assert_eq!(crate_num, LOCAL_CRATE);
     let mut arena = arena::TypedArena::default();
     let terms_cx = terms::determine_parameters_to_be_inferred(tcx, &mut arena);
@@ -42,7 +42,7 @@ fn crate_variances<'tcx>(tcx: TyCtxt<'tcx>, crate_num: CrateNum) -> &'tcx CrateV
     tcx.arena.alloc(solve::solve_constraints(constraints_cx))
 }
 
-fn variances_of<'tcx>(tcx: TyCtxt<'tcx>, item_def_id: DefId) -> &'tcx [ty::Variance] {
+fn variances_of(tcx: TyCtxt<'_>, item_def_id: DefId) -> &[ty::Variance] {
     let id = tcx.hir().as_local_hir_id(item_def_id).expect("expected local def-id");
     let unsupported = || {
         // Variance not relevant.
diff --git a/src/librustc_typeck/variance/test.rs b/src/librustc_typeck/variance/test.rs
index cefc200f5cba8..0c7ebc34e8f6d 100644
--- a/src/librustc_typeck/variance/test.rs
+++ b/src/librustc_typeck/variance/test.rs
@@ -3,7 +3,7 @@ use rustc::hir::itemlikevisit::ItemLikeVisitor;
 use rustc::ty::TyCtxt;
 use syntax::symbol::sym;
 
-pub fn test_variance<'tcx>(tcx: TyCtxt<'tcx>) {
+pub fn test_variance(tcx: TyCtxt<'_>) {
     tcx.hir().krate().visit_all_item_likes(&mut VarianceTest { tcx });
 }
 
diff --git a/src/libsyntax/attr/mod.rs b/src/libsyntax/attr/mod.rs
index 436620ae7293b..453b6ebf3c49d 100644
--- a/src/libsyntax/attr/mod.rs
+++ b/src/libsyntax/attr/mod.rs
@@ -440,12 +440,12 @@ pub fn contains_name(attrs: &[Attribute], name: Symbol) -> bool {
     })
 }
 
-pub fn find_by_name<'a>(attrs: &'a [Attribute], name: Symbol) -> Option<&'a Attribute> {
+pub fn find_by_name(attrs: &[Attribute], name: Symbol) -> Option<&Attribute> {
     attrs.iter().find(|attr| attr.check_name(name))
 }
 
-pub fn filter_by_name<'a>(attrs: &'a [Attribute], name: Symbol)
-    -> impl Iterator<Item = &'a Attribute> {
+pub fn filter_by_name(attrs: &[Attribute], name: Symbol)
+                      -> impl Iterator<Item=&Attribute> {
     attrs.iter().filter(move |attr| attr.check_name(name))
 }
 
diff --git a/src/libsyntax/ext/tt/macro_parser.rs b/src/libsyntax/ext/tt/macro_parser.rs
index 92ce3779a3c81..fc8aa4793bc61 100644
--- a/src/libsyntax/ext/tt/macro_parser.rs
+++ b/src/libsyntax/ext/tt/macro_parser.rs
@@ -901,7 +901,7 @@ fn may_begin_with(token: &Token, name: Name) -> bool {
 /// # Returns
 ///
 /// The parsed non-terminal.
-fn parse_nt<'a>(p: &mut Parser<'a>, sp: Span, name: Symbol) -> Nonterminal {
+fn parse_nt(p: &mut Parser<'_>, sp: Span, name: Symbol) -> Nonterminal {
     if name == sym::tt {
         return token::NtTT(p.parse_token_tree());
     }
diff --git a/src/libsyntax/util/parser_testing.rs b/src/libsyntax/util/parser_testing.rs
index 733c4f83e37d4..f850960624ce7 100644
--- a/src/libsyntax/util/parser_testing.rs
+++ b/src/libsyntax/util/parser_testing.rs
@@ -20,7 +20,7 @@ pub fn string_to_stream(source_str: String) -> TokenStream {
 }
 
 /// Map string to parser (via tts)
-pub fn string_to_parser<'a>(ps: &'a ParseSess, source_str: String) -> Parser<'a> {
+pub fn string_to_parser(ps: &ParseSess, source_str: String) -> Parser<'_> {
     new_parser_from_source_str(ps, PathBuf::from("bogofile").into(), source_str)
 }
 
diff --git a/src/libsyntax_ext/assert.rs b/src/libsyntax_ext/assert.rs
index 10d323ffb89f5..637614a18bcc3 100644
--- a/src/libsyntax_ext/assert.rs
+++ b/src/libsyntax_ext/assert.rs
@@ -131,7 +131,7 @@ fn parse_assert<'a>(
     Ok(Assert { cond_expr, custom_message })
 }
 
-fn parse_custom_message<'a>(parser: &mut Parser<'a>) -> Option<TokenStream> {
+fn parse_custom_message(parser: &mut Parser<'_>) -> Option<TokenStream> {
     let ts = parser.parse_tokens();
     if !ts.is_empty() {
         Some(ts)
diff --git a/src/libsyntax_ext/deriving/generic/mod.rs b/src/libsyntax_ext/deriving/generic/mod.rs
index 444cf1263ce25..12482f7248e90 100644
--- a/src/libsyntax_ext/deriving/generic/mod.rs
+++ b/src/libsyntax_ext/deriving/generic/mod.rs
@@ -331,8 +331,8 @@ pub type CombineSubstructureFunc<'a> =
 pub type EnumNonMatchCollapsedFunc<'a> =
     Box<dyn FnMut(&mut ExtCtxt<'_>, Span, (&[Ident], &[Ident]), &[P<Expr>]) -> P<Expr> + 'a>;
 
-pub fn combine_substructure<'a>(f: CombineSubstructureFunc<'a>)
-                                -> RefCell<CombineSubstructureFunc<'a>> {
+pub fn combine_substructure(f: CombineSubstructureFunc<'_>)
+                            -> RefCell<CombineSubstructureFunc<'_>> {
     RefCell::new(f)
 }
 
diff --git a/src/libsyntax_ext/deriving/generic/ty.rs b/src/libsyntax_ext/deriving/generic/ty.rs
index 90d826429da4d..02b02e9b83695 100644
--- a/src/libsyntax_ext/deriving/generic/ty.rs
+++ b/src/libsyntax_ext/deriving/generic/ty.rs
@@ -39,10 +39,10 @@ pub enum PathKind {
 }
 
 impl<'a> Path<'a> {
-    pub fn new<'r>(path: Vec<&'r str>) -> Path<'r> {
+    pub fn new(path: Vec<&str>) -> Path<'_> {
         Path::new_(path, None, Vec::new(), PathKind::Std)
     }
-    pub fn new_local<'r>(path: &'r str) -> Path<'r> {
+    pub fn new_local(path: &str) -> Path<'_> {
         Path::new_(vec![path], None, Vec::new(), PathKind::Local)
     }
     pub fn new_<'r>(path: Vec<&'r str>,
@@ -117,7 +117,7 @@ pub enum Const {
 pub fn borrowed_ptrty<'r>() -> PtrTy<'r> {
     Borrowed(None, ast::Mutability::Immutable)
 }
-pub fn borrowed<'r>(ty: Box<Ty<'r>>) -> Ty<'r> {
+pub fn borrowed(ty: Box<Ty<'_>>) -> Ty<'_> {
     Ptr(ty, borrowed_ptrty())
 }