1 files changed, 23 insertions, 13 deletions

diff --git a/compiler/rustc_hir/src/hir.rs b/compiler/rustc_hir/src/hir.rs
index 2abebbd0303..acd254ae85c 100644
--- a/compiler/rustc_hir/src/hir.rs
+++ b/compiler/rustc_hir/src/hir.rs
@@ -28,7 +28,7 @@ pub struct Lifetime {
     pub span: Span,
 
     /// Either "`'a`", referring to a named lifetime definition,
-    /// or "``" (i.e., `kw::Invalid`), for elision placeholders.
+    /// or "``" (i.e., `kw::Empty`), for elision placeholders.
     ///
     /// HIR lowering inserts these placeholders in type paths that
     /// refer to type definitions needing lifetime parameters,
@@ -290,6 +290,14 @@ impl GenericArg<'_> {
             GenericArg::Const(_) => "const",
         }
     }
+
+    pub fn to_ord(&self, feats: &rustc_feature::Features) -> ast::ParamKindOrd {
+        match self {
+            GenericArg::Lifetime(_) => ast::ParamKindOrd::Lifetime,
+            GenericArg::Type(_) => ast::ParamKindOrd::Type,
+            GenericArg::Const(_) => ast::ParamKindOrd::Const { unordered: feats.const_generics },
+        }
+    }
 }
 
 #[derive(Debug, HashStable_Generic)]
@@ -378,9 +386,9 @@ impl GenericBound<'_> {
 
     pub fn span(&self) -> Span {
         match self {
-            &GenericBound::Trait(ref t, ..) => t.span,
-            &GenericBound::LangItemTrait(_, span, ..) => span,
-            &GenericBound::Outlives(ref l) => l.span,
+            GenericBound::Trait(t, ..) => t.span,
+            GenericBound::LangItemTrait(_, span, ..) => *span,
+            GenericBound::Outlives(l) => l.span,
         }
     }
 }
@@ -418,6 +426,8 @@ pub enum GenericParamKind<'hir> {
     },
     Const {
         ty: &'hir Ty<'hir>,
+        /// Optional default value for the const generic param
+        default: Option<AnonConst>,
     },
 }
 
@@ -536,9 +546,9 @@ pub enum WherePredicate<'hir> {
 impl WherePredicate<'_> {
     pub fn span(&self) -> Span {
         match self {
-            &WherePredicate::BoundPredicate(ref p) => p.span,
-            &WherePredicate::RegionPredicate(ref p) => p.span,
-            &WherePredicate::EqPredicate(ref p) => p.span,
+            WherePredicate::BoundPredicate(p) => p.span,
+            WherePredicate::RegionPredicate(p) => p.span,
+            WherePredicate::EqPredicate(p) => p.span,
         }
     }
 }
@@ -607,7 +617,7 @@ pub struct Crate<'hir> {
     // over the ids in increasing order. In principle it should not
     // matter what order we visit things in, but in *practice* it
     // does, because it can affect the order in which errors are
-    // detected, which in turn can make compile-fail tests yield
+    // detected, which in turn can make UI tests yield
     // slightly different results.
     pub items: BTreeMap<HirId, Item<'hir>>,
 
@@ -760,9 +770,9 @@ pub struct Pat<'hir> {
     pub default_binding_modes: bool,
 }
 
-impl Pat<'_> {
+impl<'hir> Pat<'hir> {
     // FIXME(#19596) this is a workaround, but there should be a better way
-    fn walk_short_(&self, it: &mut impl FnMut(&Pat<'_>) -> bool) -> bool {
+    fn walk_short_(&self, it: &mut impl FnMut(&Pat<'hir>) -> bool) -> bool {
         if !it(self) {
             return false;
         }
@@ -785,12 +795,12 @@ impl Pat<'_> {
     /// Note that when visiting e.g. `Tuple(ps)`,
     /// if visiting `ps[0]` returns `false`,
     /// then `ps[1]` will not be visited.
-    pub fn walk_short(&self, mut it: impl FnMut(&Pat<'_>) -> bool) -> bool {
+    pub fn walk_short(&self, mut it: impl FnMut(&Pat<'hir>) -> bool) -> bool {
         self.walk_short_(&mut it)
     }
 
     // FIXME(#19596) this is a workaround, but there should be a better way
-    fn walk_(&self, it: &mut impl FnMut(&Pat<'_>) -> bool) {
+    fn walk_(&self, it: &mut impl FnMut(&Pat<'hir>) -> bool) {
         if !it(self) {
             return;
         }
@@ -810,7 +820,7 @@ impl Pat<'_> {
     /// Walk the pattern in left-to-right order.
     ///
     /// If `it(pat)` returns `false`, the children are not visited.
-    pub fn walk(&self, mut it: impl FnMut(&Pat<'_>) -> bool) {
+    pub fn walk(&self, mut it: impl FnMut(&Pat<'hir>) -> bool) {
         self.walk_(&mut it)
     }