rustc: deny(unused_lifetimes).

Author: eddyb

src/librustc/hir/map/collector.rs

@@ -589,7 +589,7 @@ struct HirItemLike<T> {
     hash_bodies: bool,
 }
 
-impl<'a, 'hir, T> HashStable<StableHashingContext<'hir>> for HirItemLike<T>
+impl<'hir, T> HashStable<StableHashingContext<'hir>> for HirItemLike<T>
     where T: HashStable<StableHashingContext<'hir>>
 {
     fn hash_stable<W: StableHasherResult>(&self,

src/librustc/ich/hcx.rs

@@ -393,7 +393,7 @@ impl<'a> HashStable<StableHashingContext<'a>> for DelimSpan {
     }
 }
 
-pub fn hash_stable_trait_impls<'a, 'gcx, W>(
+pub fn hash_stable_trait_impls<'a, W>(
     hcx: &mut StableHashingContext<'a>,
     hasher: &mut StableHasher<W>,
     blanket_impls: &[DefId],

src/librustc/ich/impls_ty.rs

@@ -135,7 +135,7 @@ impl<'gcx> HashStable<StableHashingContext<'gcx>> for ty::BoundVar {
     }
 }
 
-impl<'a, 'gcx, T> HashStable<StableHashingContext<'a>> for ty::Binder<T>
+impl<'a, T> HashStable<StableHashingContext<'a>> for ty::Binder<T>
     where T: HashStable<StableHashingContext<'a>>
 {
     fn hash_stable<W: StableHasherResult>(&self,
@@ -192,7 +192,7 @@ impl<'a> ToStableHashKey<StableHashingContext<'a>> for region::Scope {
     }
 }
 
-impl<'a, 'gcx> HashStable<StableHashingContext<'a>>
+impl<'a> HashStable<StableHashingContext<'a>>
 for ty::TyVid
 {
     fn hash_stable<W: StableHasherResult>(&self,
@@ -204,7 +204,7 @@ for ty::TyVid
     }
 }
 
-impl<'a, 'gcx> HashStable<StableHashingContext<'a>>
+impl<'a> HashStable<StableHashingContext<'a>>
 for ty::IntVid
 {
     fn hash_stable<W: StableHasherResult>(&self,
@@ -216,7 +216,7 @@ for ty::IntVid
     }
 }
 
-impl<'a, 'gcx> HashStable<StableHashingContext<'a>>
+impl<'a> HashStable<StableHashingContext<'a>>
 for ty::FloatVid
 {
     fn hash_stable<W: StableHasherResult>(&self,
@@ -228,7 +228,7 @@ for ty::FloatVid
     }
 }
 
-impl<'a, 'gcx, T> HashStable<StableHashingContext<'a>>
+impl<'a, T> HashStable<StableHashingContext<'a>>
 for ty::steal::Steal<T>
     where T: HashStable<StableHashingContext<'a>>
 {

src/librustc/infer/region_constraints/mod.rs

@@ -858,7 +858,7 @@ impl<'a, 'gcx, 'tcx> GenericKind<'tcx> {
     }
 }
 
-impl<'a, 'gcx, 'tcx> VerifyBound<'tcx> {
+impl<'tcx> VerifyBound<'tcx> {
     pub fn must_hold(&self) -> bool {
         match self {
             VerifyBound::IfEq(..) => false,

src/librustc/lib.rs

@@ -30,6 +30,7 @@
 
 #![deny(rust_2018_idioms)]
 #![deny(internal)]
+#![deny(unused_lifetimes)]
 #![allow(explicit_outlives_requirements)]
 
 #![feature(arbitrary_self_types)]

src/librustc/lint/context.rs

@@ -566,7 +566,7 @@ impl LintPassObject for EarlyLintPassObject {}
 
 impl LintPassObject for LateLintPassObject {}
 
-pub trait LintContext<'tcx>: Sized {
+pub trait LintContext: Sized {
     type PassObject: LintPassObject;
 
     fn sess(&self) -> &Session;
@@ -700,7 +700,7 @@ impl<'a, T: EarlyLintPass> EarlyContextAndPass<'a, T> {
     }
 }
 
-impl<'a, 'tcx> LintContext<'tcx> for LateContext<'a, 'tcx> {
+impl LintContext for LateContext<'_, '_> {
     type PassObject = LateLintPassObject;
 
     /// Gets the overall compiler `Session` object.
@@ -728,7 +728,7 @@ impl<'a, 'tcx> LintContext<'tcx> for LateContext<'a, 'tcx> {
     }
 }
 
-impl<'a> LintContext<'a> for EarlyContext<'a> {
+impl LintContext for EarlyContext<'_> {
     type PassObject = EarlyLintPassObject;
 
     /// Gets the overall compiler `Session` object.

src/librustc/macros.rs

@@ -80,7 +80,7 @@ macro_rules! impl_stable_hash_for {
     // We want to use the enum name both in the `impl ... for $enum_name` as well as for
     // importing all the variants. Unfortunately it seems we have to take the name
     // twice for this purpose
-    (impl<$($lt:lifetime $(: $lt_bound:lifetime)? ),* $(,)? $($T:ident),* $(,)?>
+    (impl<$($T:ident),* $(,)?>
         for enum $enum_name:path
         [ $enum_path:path ]
     {
@@ -91,7 +91,7 @@ macro_rules! impl_stable_hash_for {
            $( { $($named_field:ident $(-> $named_delegate:tt)?),* } )?
         ),* $(,)?
     }) => {
-        impl<'a, $($lt $(: $lt_bound)?,)* $($T,)*>
+        impl<$($T,)*>
             ::rustc_data_structures::stable_hasher::HashStable<$crate::ich::StableHashingContext<'a>>
             for $enum_name
             where $($T: ::rustc_data_structures::stable_hasher::HashStable<$crate::ich::StableHashingContext<'a>>),*
@@ -117,13 +117,13 @@ macro_rules! impl_stable_hash_for {
     // Structs
     (struct $struct_name:path { $($field:ident $(-> $delegate:tt)?),* $(,)? }) => {
         impl_stable_hash_for!(
-            impl<'tcx> for struct $struct_name { $($field $(-> $delegate)?),* }
+            impl<> for struct $struct_name { $($field $(-> $delegate)?),* }
         );
     };
-    (impl<$($lt:lifetime $(: $lt_bound:lifetime)? ),* $(,)? $($T:ident),* $(,)?> for struct $struct_name:path {
+    (impl<$($T:ident),* $(,)?> for struct $struct_name:path {
         $($field:ident $(-> $delegate:tt)?),* $(,)?
     }) => {
-        impl<'a, $($lt $(: $lt_bound)?,)* $($T,)*>
+        impl<$($T,)*>
             ::rustc_data_structures::stable_hasher::HashStable<$crate::ich::StableHashingContext<'a>> for $struct_name
             where $($T: ::rustc_data_structures::stable_hasher::HashStable<$crate::ich::StableHashingContext<'a>>),*
         {
@@ -143,12 +143,12 @@ macro_rules! impl_stable_hash_for {
     // We cannot use normal parentheses here, the parser won't allow it
     (tuple_struct $struct_name:path { $($field:ident $(-> $delegate:tt)?),*  $(,)? }) => {
         impl_stable_hash_for!(
-            impl<'tcx> for tuple_struct $struct_name { $($field $(-> $delegate)?),* }
+            impl<> for tuple_struct $struct_name { $($field $(-> $delegate)?),* }
         );
     };
-    (impl<$($lt:lifetime $(: $lt_bound:lifetime)? ),* $(,)? $($T:ident),* $(,)?>
+    (impl<$($T:ident),* $(,)?>
      for tuple_struct $struct_name:path { $($field:ident $(-> $delegate:tt)?),*  $(,)? }) => {
-        impl<'a, $($lt $(: $lt_bound)?,)* $($T,)*>
+        impl<$($T,)*>
             ::rustc_data_structures::stable_hasher::HashStable<$crate::ich::StableHashingContext<'a>> for $struct_name
             where $($T: ::rustc_data_structures::stable_hasher::HashStable<$crate::ich::StableHashingContext<'a>>),*
         {
@@ -170,7 +170,7 @@ macro_rules! impl_stable_hash_for {
 macro_rules! impl_stable_hash_for_spanned {
     ($T:path) => (
 
-        impl<'a, 'tcx> HashStable<StableHashingContext<'a>> for ::syntax::source_map::Spanned<$T>
+        impl HashStable<StableHashingContext<'a>> for ::syntax::source_map::Spanned<$T>
         {
             #[inline]
             fn hash_stable<W: StableHasherResult>(&self,

src/librustc/mir/interpret/pointer.rs

@@ -105,7 +105,7 @@ impl From<AllocId> for Pointer {
     }
 }
 
-impl<'tcx> Pointer<()> {
+impl Pointer<()> {
     #[inline(always)]
     pub fn new(alloc_id: AllocId, offset: Size) -> Self {
         Pointer { alloc_id, offset, tag: () }

src/librustc/mir/interpret/value.rs

@@ -146,7 +146,7 @@ impl<Tag> From<Double> for Scalar<Tag> {
     }
 }
 
-impl<'tcx> Scalar<()> {
+impl Scalar<()> {
     #[inline(always)]
     fn check_data(data: u128, size: u8) {
         debug_assert_eq!(truncate(data, Size::from_bytes(size as u64)), data,

src/librustc/mir/visit.rs

@@ -967,7 +967,7 @@ pub enum PlaceContext {
     NonUse(NonUseContext),
 }
 
-impl<'tcx> PlaceContext {
+impl PlaceContext {
     /// Returns `true` if this place context represents a drop.
     pub fn is_drop(&self) -> bool {
         match *self {