diff --git a/src/librustc/cfg/construct.rs b/src/librustc/cfg/construct.rs
index a7750edbb6f4..2932edd347af 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 db168d99a080..88fc7fbfad51 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 93c22c3e713c..b8c6c1e37238 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_borrowck/borrowck/check_loans.rs b/src/librustc_borrowck/borrowck/check_loans.rs
index 714b7c27200e..a098cd176123 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 3c7f19f7fbf4..8763a6bc066b 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_codegen_llvm/back/write.rs b/src/librustc_codegen_llvm/back/write.rs
index 3638730707f3..b135605cf02d 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_ssa/back/symbol_export.rs b/src/librustc_codegen_ssa/back/symbol_export.rs
index 3e0f030527f4..b64c9a60d971 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/debuginfo/mod.rs b/src/librustc_codegen_ssa/debuginfo/mod.rs
index d60a2e0cb135..c9b1c0260e8c 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_data_structures/graph/mod.rs b/src/librustc_data_structures/graph/mod.rs
index 2787fa3c6b1e..e59085a9e3a9 100644
--- a/src/librustc_data_structures/graph/mod.rs
+++ b/src/librustc_data_structures/graph/mod.rs
@@ -26,10 +26,10 @@ 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;
 
     fn depth_first_search(&self, from: Self::Node) -> iterate::DepthFirstSearch<'_, Self>
     where
@@ -48,10 +48,10 @@ 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 5ad2a71e1d73..9442bb3cdec3 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 b390c4195729..5ff0cbf58c79 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_mir/borrow_check/mod.rs b/src/librustc_mir/borrow_check/mod.rs
index 4872440f5bd4..0072fcb22f13 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 1d9e6064c416..b5630251e583 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/path_utils.rs b/src/librustc_mir/borrow_check/path_utils.rs
index aa2b177e54ed..538ac6881d90 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 222ce6d1c968..f679a00035d7 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/mod.rs b/src/librustc_mir/build/mod.rs
index ad970de466cf..80a035d8287f 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/librustdoc/clean/mod.rs b/src/librustdoc/clean/mod.rs
index 3fe048a6986b..dae72ebd52d3 100644
--- a/src/librustdoc/clean/mod.rs
+++ b/src/librustdoc/clean/mod.rs
@@ -392,7 +392,7 @@ impl fmt::Debug for Item {
 impl Item {
     /// Finds the `doc` attribute as a NameValue and returns the corresponding
     /// value found.
-    pub fn doc_value<'a>(&'a self) -> Option<&'a str> {
+    pub fn doc_value(&self) -> Option<&str> {
         self.attrs.doc_value()
     }
     /// Finds all `doc` attributes as NameValues and returns their corresponding values, joined
@@ -699,11 +699,11 @@ impl<'a> Iterator for ListAttributesIter<'a> {
 
 pub trait AttributesExt {
     /// Finds an attribute as List and returns the list of attributes nested inside.
-    fn lists<'a>(&'a self, name: Symbol) -> ListAttributesIter<'a>;
+    fn lists(&self, name: Symbol) -> ListAttributesIter<'_>;
 }
 
 impl AttributesExt for [ast::Attribute] {
-    fn lists<'a>(&'a self, name: Symbol) -> ListAttributesIter<'a> {
+    fn lists(&self, name: Symbol) -> ListAttributesIter<'_> {
         ListAttributesIter {
             attrs: self.iter(),
             current_list: Vec::new().into_iter(),
@@ -952,7 +952,7 @@ impl Attributes {
 
     /// Finds the `doc` attribute as a NameValue and returns the corresponding
     /// value found.
-    pub fn doc_value<'a>(&'a self) -> Option<&'a str> {
+    pub fn doc_value(&self) -> Option<&str> {
         self.doc_strings.first().map(|s| s.as_str())
     }
 
@@ -1037,7 +1037,7 @@ impl Hash for Attributes {
 }
 
 impl AttributesExt for Attributes {
-    fn lists<'a>(&'a self, name: Symbol) -> ListAttributesIter<'a> {
+    fn lists(&self, name: Symbol) -> ListAttributesIter<'_> {
         self.other_attrs.lists(name)
     }
 }
diff --git a/src/libsyntax_ext/deriving/generic/mod.rs b/src/libsyntax_ext/deriving/generic/mod.rs
index 444cf1263ce2..12482f7248e9 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 90d826429da4..02b02e9b8369 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())
 }