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-rw-r--r--compiler/rustc_parse/src/parser/attr.rs2
-rw-r--r--compiler/rustc_parse/src/parser/expr.rs20
-rw-r--r--compiler/rustc_parse/src/parser/generics.rs11
-rw-r--r--compiler/rustc_parse/src/parser/item.rs2
-rw-r--r--compiler/rustc_parse/src/parser/mod.rs36
-rw-r--r--compiler/rustc_parse/src/parser/path.rs4
-rw-r--r--compiler/rustc_parse/src/parser/ty.rs177
7 files changed, 153 insertions, 99 deletions
diff --git a/compiler/rustc_parse/src/parser/attr.rs b/compiler/rustc_parse/src/parser/attr.rs
index 7f6afeba28c..acd338156ce 100644
--- a/compiler/rustc_parse/src/parser/attr.rs
+++ b/compiler/rustc_parse/src/parser/attr.rs
@@ -399,7 +399,7 @@ impl<'a> Parser<'a> {
     }
 
     /// Matches `COMMASEP(meta_item_inner)`.
-    pub(crate) fn parse_meta_seq_top(&mut self) -> PResult<'a, ThinVec<ast::MetaItemInner>> {
+    pub fn parse_meta_seq_top(&mut self) -> PResult<'a, ThinVec<ast::MetaItemInner>> {
         // Presumably, the majority of the time there will only be one attr.
         let mut nmis = ThinVec::with_capacity(1);
         while self.token != token::Eof {
diff --git a/compiler/rustc_parse/src/parser/expr.rs b/compiler/rustc_parse/src/parser/expr.rs
index d0604f76317..1499808966c 100644
--- a/compiler/rustc_parse/src/parser/expr.rs
+++ b/compiler/rustc_parse/src/parser/expr.rs
@@ -2077,7 +2077,7 @@ impl<'a> Parser<'a> {
         (token::Lit { symbol: name, suffix: None, kind: token::Char }, span)
     }
 
-    fn mk_meta_item_lit_char(name: Symbol, span: Span) -> MetaItemLit {
+    pub fn mk_meta_item_lit_char(name: Symbol, span: Span) -> MetaItemLit {
         ast::MetaItemLit {
             symbol: name,
             suffix: None,
@@ -2086,7 +2086,7 @@ impl<'a> Parser<'a> {
         }
     }
 
-    fn handle_missing_lit<L>(
+    pub fn handle_missing_lit<L>(
         &mut self,
         mk_lit_char: impl FnOnce(Symbol, Span) -> L,
     ) -> PResult<'a, L> {
@@ -2156,7 +2156,7 @@ impl<'a> Parser<'a> {
 
     /// Keep this in sync with `Token::can_begin_literal_maybe_minus` and
     /// `Lit::from_token` (excluding unary negation).
-    fn eat_token_lit(&mut self) -> Option<token::Lit> {
+    pub fn eat_token_lit(&mut self) -> Option<token::Lit> {
         let check_expr = |expr: Box<Expr>| {
             if let ast::ExprKind::Lit(token_lit) = expr.kind {
                 Some(token_lit)
@@ -2397,20 +2397,24 @@ impl<'a> Parser<'a> {
         let before = self.prev_token;
         let binder = if self.check_keyword(exp!(For)) {
             let lo = self.token.span;
-            let (lifetime_defs, _) = self.parse_late_bound_lifetime_defs()?;
+            let (bound_vars, _) = self.parse_higher_ranked_binder()?;
             let span = lo.to(self.prev_token.span);
 
             self.psess.gated_spans.gate(sym::closure_lifetime_binder, span);
 
-            ClosureBinder::For { span, generic_params: lifetime_defs }
+            ClosureBinder::For { span, generic_params: bound_vars }
         } else {
             ClosureBinder::NotPresent
         };
 
         let constness = self.parse_closure_constness();
 
-        let movability =
-            if self.eat_keyword(exp!(Static)) { Movability::Static } else { Movability::Movable };
+        let movability = if self.eat_keyword(exp!(Static)) {
+            self.psess.gated_spans.gate(sym::coroutines, self.prev_token.span);
+            Movability::Static
+        } else {
+            Movability::Movable
+        };
 
         let coroutine_kind = if self.token_uninterpolated_span().at_least_rust_2018() {
             self.parse_coroutine_kind(Case::Sensitive)
@@ -3090,7 +3094,7 @@ impl<'a> Parser<'a> {
         if let Some((ident, is_raw)) = self.token.lifetime() {
             // Disallow `'fn`, but with a better error message than `expect_lifetime`.
             if matches!(is_raw, IdentIsRaw::No) && ident.without_first_quote().is_reserved() {
-                self.dcx().emit_err(errors::InvalidLabel { span: ident.span, name: ident.name });
+                self.dcx().emit_err(errors::KeywordLabel { span: ident.span });
             }
 
             self.bump();
diff --git a/compiler/rustc_parse/src/parser/generics.rs b/compiler/rustc_parse/src/parser/generics.rs
index 4a8530a2b38..eb684c3a62f 100644
--- a/compiler/rustc_parse/src/parser/generics.rs
+++ b/compiler/rustc_parse/src/parser/generics.rs
@@ -172,8 +172,11 @@ impl<'a> Parser<'a> {
         })
     }
 
-    /// Parses a (possibly empty) list of lifetime and type parameters, possibly including
-    /// a trailing comma and erroneous trailing attributes.
+    /// Parse a (possibly empty) list of generic (lifetime, type, const) parameters.
+    ///
+    /// ```ebnf
+    /// GenericParams = (GenericParam ("," GenericParam)* ","?)?
+    /// ```
     pub(super) fn parse_generic_params(&mut self) -> PResult<'a, ThinVec<ast::GenericParam>> {
         let mut params = ThinVec::new();
         let mut done = false;
@@ -520,7 +523,7 @@ impl<'a> Parser<'a> {
         // * `for<'a> Trait1<'a>: Trait2<'a /* ok */>`
         // * `(for<'a> Trait1<'a>): Trait2<'a /* not ok */>`
         // * `for<'a> for<'b> Trait1<'a, 'b>: Trait2<'a /* ok */, 'b /* not ok */>`
-        let (lifetime_defs, _) = self.parse_late_bound_lifetime_defs()?;
+        let (bound_vars, _) = self.parse_higher_ranked_binder()?;
 
         // Parse type with mandatory colon and (possibly empty) bounds,
         // or with mandatory equality sign and the second type.
@@ -528,7 +531,7 @@ impl<'a> Parser<'a> {
         if self.eat(exp!(Colon)) {
             let bounds = self.parse_generic_bounds()?;
             Ok(ast::WherePredicateKind::BoundPredicate(ast::WhereBoundPredicate {
-                bound_generic_params: lifetime_defs,
+                bound_generic_params: bound_vars,
                 bounded_ty: ty,
                 bounds,
             }))
diff --git a/compiler/rustc_parse/src/parser/item.rs b/compiler/rustc_parse/src/parser/item.rs
index ca89eb1e2cf..fd9fb65417c 100644
--- a/compiler/rustc_parse/src/parser/item.rs
+++ b/compiler/rustc_parse/src/parser/item.rs
@@ -43,7 +43,7 @@ impl<'a> Parser<'a> {
             self.expect(exp!(OpenBrace))?;
             let (inner_attrs, items, inner_span) = self.parse_mod(exp!(CloseBrace))?;
             attrs.extend(inner_attrs);
-            ModKind::Loaded(items, Inline::Yes, inner_span, Ok(()))
+            ModKind::Loaded(items, Inline::Yes, inner_span)
         };
         Ok(ItemKind::Mod(safety, ident, mod_kind))
     }
diff --git a/compiler/rustc_parse/src/parser/mod.rs b/compiler/rustc_parse/src/parser/mod.rs
index 41ed1f95a01..d19114df812 100644
--- a/compiler/rustc_parse/src/parser/mod.rs
+++ b/compiler/rustc_parse/src/parser/mod.rs
@@ -24,7 +24,7 @@ pub use diagnostics::AttemptLocalParseRecovery;
 pub(crate) use expr::ForbiddenLetReason;
 pub(crate) use item::{FnContext, FnParseMode};
 pub use pat::{CommaRecoveryMode, RecoverColon, RecoverComma};
-use path::PathStyle;
+pub use path::PathStyle;
 use rustc_ast::token::{
     self, IdentIsRaw, InvisibleOrigin, MetaVarKind, NtExprKind, NtPatKind, Token, TokenKind,
 };
@@ -285,7 +285,7 @@ pub enum FollowedByType {
 }
 
 #[derive(Copy, Clone, Debug)]
-enum Trailing {
+pub enum Trailing {
     No,
     Yes,
 }
@@ -494,7 +494,7 @@ impl<'a> Parser<'a> {
     /// This method will automatically add `tok` to `expected_token_types` if `tok` is not
     /// encountered.
     #[inline]
-    fn check(&mut self, exp: ExpTokenPair<'_>) -> bool {
+    pub fn check(&mut self, exp: ExpTokenPair<'_>) -> bool {
         let is_present = self.token == *exp.tok;
         if !is_present {
             self.expected_token_types.insert(exp.token_type);
@@ -633,7 +633,7 @@ impl<'a> Parser<'a> {
     }
 
     /// Consume a sequence produced by a metavar expansion, if present.
-    fn eat_metavar_seq<T>(
+    pub fn eat_metavar_seq<T>(
         &mut self,
         mv_kind: MetaVarKind,
         f: impl FnMut(&mut Parser<'a>) -> PResult<'a, T>,
@@ -1094,7 +1094,7 @@ impl<'a> Parser<'a> {
     /// Parses a comma-separated sequence delimited by parentheses (e.g. `(x, y)`).
     /// The function `f` must consume tokens until reaching the next separator or
     /// closing bracket.
-    fn parse_paren_comma_seq<T>(
+    pub fn parse_paren_comma_seq<T>(
         &mut self,
         f: impl FnMut(&mut Parser<'a>) -> PResult<'a, T>,
     ) -> PResult<'a, (ThinVec<T>, Trailing)> {
@@ -1355,7 +1355,8 @@ impl<'a> Parser<'a> {
             AttrArgs::Delimited(args)
         } else if self.eat(exp!(Eq)) {
             let eq_span = self.prev_token.span;
-            AttrArgs::Eq { eq_span, expr: self.parse_expr_force_collect()? }
+            let expr = self.parse_expr_force_collect()?;
+            AttrArgs::Eq { eq_span, expr }
         } else {
             AttrArgs::Empty
         })
@@ -1388,15 +1389,26 @@ impl<'a> Parser<'a> {
             // matching `CloseDelim` we are *after* the delimited sequence,
             // i.e. at depth `d - 1`.
             let target_depth = self.token_cursor.stack.len() - 1;
-            loop {
-                // Advance one token at a time, so `TokenCursor::next()`
-                // can capture these tokens if necessary.
+
+            if let Capturing::No = self.capture_state.capturing {
+                // We are not capturing tokens, so skip to the end of the
+                // delimited sequence. This is a perf win when dealing with
+                // declarative macros that pass large `tt` fragments through
+                // multiple rules, as seen in the uom-0.37.0 crate.
+                self.token_cursor.curr.bump_to_end();
                 self.bump();
-                if self.token_cursor.stack.len() == target_depth {
-                    debug_assert!(self.token.kind.close_delim().is_some());
-                    break;
+                debug_assert_eq!(self.token_cursor.stack.len(), target_depth);
+            } else {
+                loop {
+                    // Advance one token at a time, so `TokenCursor::next()`
+                    // can capture these tokens if necessary.
+                    self.bump();
+                    if self.token_cursor.stack.len() == target_depth {
+                        break;
+                    }
                 }
             }
+            debug_assert!(self.token.kind.close_delim().is_some());
 
             // Consume close delimiter
             self.bump();
diff --git a/compiler/rustc_parse/src/parser/path.rs b/compiler/rustc_parse/src/parser/path.rs
index 37fc723cd89..86045648859 100644
--- a/compiler/rustc_parse/src/parser/path.rs
+++ b/compiler/rustc_parse/src/parser/path.rs
@@ -26,7 +26,7 @@ use crate::parser::{
 
 /// Specifies how to parse a path.
 #[derive(Copy, Clone, PartialEq)]
-pub(super) enum PathStyle {
+pub enum PathStyle {
     /// In some contexts, notably in expressions, paths with generic arguments are ambiguous
     /// with something else. For example, in expressions `segment < ....` can be interpreted
     /// as a comparison and `segment ( ....` can be interpreted as a function call.
@@ -150,7 +150,7 @@ impl<'a> Parser<'a> {
         true
     }
 
-    pub(super) fn parse_path(&mut self, style: PathStyle) -> PResult<'a, Path> {
+    pub fn parse_path(&mut self, style: PathStyle) -> PResult<'a, Path> {
         self.parse_path_inner(style, None)
     }
 
diff --git a/compiler/rustc_parse/src/parser/ty.rs b/compiler/rustc_parse/src/parser/ty.rs
index 290f0a440af..6168647183f 100644
--- a/compiler/rustc_parse/src/parser/ty.rs
+++ b/compiler/rustc_parse/src/parser/ty.rs
@@ -137,14 +137,37 @@ impl<'a> Parser<'a> {
     /// The difference from `parse_ty` is that this version allows `...`
     /// (`CVarArgs`) at the top level of the type.
     pub(super) fn parse_ty_for_param(&mut self) -> PResult<'a, Box<Ty>> {
-        self.parse_ty_common(
+        let ty = self.parse_ty_common(
             AllowPlus::Yes,
             AllowCVariadic::Yes,
             RecoverQPath::Yes,
             RecoverReturnSign::Yes,
             None,
             RecoverQuestionMark::Yes,
-        )
+        )?;
+
+        // Recover a trailing `= EXPR` if present.
+        if self.may_recover()
+            && self.check_noexpect(&token::Eq)
+            && self.look_ahead(1, |tok| tok.can_begin_expr())
+        {
+            let snapshot = self.create_snapshot_for_diagnostic();
+            self.bump();
+            let eq_span = self.prev_token.span;
+            match self.parse_expr() {
+                Ok(e) => {
+                    self.dcx()
+                        .struct_span_err(eq_span.to(e.span), "parameter defaults are not supported")
+                        .emit();
+                }
+                Err(diag) => {
+                    diag.cancel();
+                    self.restore_snapshot(snapshot);
+                }
+            }
+        }
+
+        Ok(ty)
     }
 
     /// Parses a type in restricted contexts where `+` is not permitted.
@@ -308,11 +331,11 @@ impl<'a> Parser<'a> {
             // Function pointer type or bound list (trait object type) starting with a poly-trait.
             //   `for<'lt> [unsafe] [extern "ABI"] fn (&'lt S) -> T`
             //   `for<'lt> Trait1<'lt> + Trait2 + 'a`
-            let (lifetime_defs, _) = self.parse_late_bound_lifetime_defs()?;
+            let (bound_vars, _) = self.parse_higher_ranked_binder()?;
             if self.check_fn_front_matter(false, Case::Sensitive) {
                 self.parse_ty_fn_ptr(
                     lo,
-                    lifetime_defs,
+                    bound_vars,
                     Some(self.prev_token.span.shrink_to_lo()),
                     recover_return_sign,
                 )?
@@ -326,7 +349,7 @@ impl<'a> Parser<'a> {
                     let path = self.parse_path(PathStyle::Type)?;
                     let parse_plus = allow_plus == AllowPlus::Yes && self.check_plus();
                     let kind = self.parse_remaining_bounds_path(
-                        lifetime_defs,
+                        bound_vars,
                         path,
                         lo,
                         parse_plus,
@@ -359,7 +382,7 @@ impl<'a> Parser<'a> {
                     let path = self.parse_path(PathStyle::Type)?;
                     let parse_plus = allow_plus == AllowPlus::Yes && self.check_plus();
                     self.parse_remaining_bounds_path(
-                        lifetime_defs,
+                        bound_vars,
                         path,
                         lo,
                         parse_plus,
@@ -443,7 +466,7 @@ impl<'a> Parser<'a> {
             let ty = ts.into_iter().next().unwrap();
             let maybe_bounds = allow_plus == AllowPlus::Yes && self.token.is_like_plus();
             match ty.kind {
-                // `(TY_BOUND_NOPAREN) + BOUND + ...`.
+                // `"(" BareTraitBound ")" "+" Bound "+" ...`.
                 TyKind::Path(None, path) if maybe_bounds => self.parse_remaining_bounds_path(
                     ThinVec::new(),
                     path,
@@ -853,10 +876,13 @@ impl<'a> Parser<'a> {
         Ok(TyKind::ImplTrait(ast::DUMMY_NODE_ID, bounds))
     }
 
-    fn parse_precise_capturing_args(
-        &mut self,
-    ) -> PResult<'a, (ThinVec<PreciseCapturingArg>, Span)> {
-        let lo = self.token.span;
+    /// Parse a use-bound aka precise capturing list.
+    ///
+    /// ```ebnf
+    /// UseBound = "use" "<" (PreciseCapture ("," PreciseCapture)* ","?)? ">"
+    /// PreciseCapture = "Self" | Ident | Lifetime
+    /// ```
+    fn parse_use_bound(&mut self, lo: Span, parens: ast::Parens) -> PResult<'a, GenericBound> {
         self.expect_lt()?;
         let (args, _, _) = self.parse_seq_to_before_tokens(
             &[exp!(Gt)],
@@ -882,7 +908,13 @@ impl<'a> Parser<'a> {
             },
         )?;
         self.expect_gt()?;
-        Ok((args, lo.to(self.prev_token.span)))
+
+        if let ast::Parens::Yes = parens {
+            self.expect(exp!(CloseParen))?;
+            self.report_parenthesized_bound(lo, self.prev_token.span, "precise capturing lists");
+        }
+
+        Ok(GenericBound::Use(args, lo.to(self.prev_token.span)))
     }
 
     /// Is a `dyn B0 + ... + Bn` type allowed here?
@@ -940,9 +972,10 @@ impl<'a> Parser<'a> {
         self.parse_generic_bounds_common(AllowPlus::Yes)
     }
 
-    /// Parses bounds of a type parameter `BOUND + BOUND + ...`, possibly with trailing `+`.
+    /// Parse generic bounds.
     ///
-    /// See `parse_generic_bound` for the `BOUND` grammar.
+    /// Only if `allow_plus` this parses a `+`-separated list of bounds (trailing `+` is admitted).
+    /// Otherwise, this only parses a single bound or none.
     fn parse_generic_bounds_common(&mut self, allow_plus: AllowPlus) -> PResult<'a, GenericBounds> {
         let mut bounds = Vec::new();
 
@@ -988,48 +1021,56 @@ impl<'a> Parser<'a> {
             || self.check_keyword(exp!(Use))
     }
 
-    /// Parses a bound according to the grammar:
+    /// Parse a bound.
+    ///
     /// ```ebnf
-    /// BOUND = TY_BOUND | LT_BOUND
+    /// Bound = LifetimeBound | UseBound | TraitBound
     /// ```
     fn parse_generic_bound(&mut self) -> PResult<'a, GenericBound> {
-        let lo = self.token.span;
         let leading_token = self.prev_token;
+        let lo = self.token.span;
+
+        // We only admit parenthesized *trait* bounds. However, we want to gracefully recover from
+        // other kinds of parenthesized bounds, so parse the opening parenthesis *here*.
+        //
+        // In the future we might want to lift this syntactic restriction and
+        // introduce "`GenericBound::Paren(Box<GenericBound>)`".
         let parens = if self.eat(exp!(OpenParen)) { ast::Parens::Yes } else { ast::Parens::No };
 
-        let bound = if self.token.is_lifetime() {
-            self.parse_generic_lt_bound(lo, parens)?
+        if self.token.is_lifetime() {
+            self.parse_lifetime_bound(lo, parens)
         } else if self.eat_keyword(exp!(Use)) {
-            // parse precise captures, if any. This is `use<'lt, 'lt, P, P>`; a list of
-            // lifetimes and ident params (including SelfUpper). These are validated later
-            // for order, duplication, and whether they actually reference params.
-            let use_span = self.prev_token.span;
-            let (args, args_span) = self.parse_precise_capturing_args()?;
-            GenericBound::Use(args, use_span.to(args_span))
+            self.parse_use_bound(lo, parens)
         } else {
-            self.parse_generic_ty_bound(lo, parens, &leading_token)?
-        };
-
-        Ok(bound)
+            self.parse_trait_bound(lo, parens, &leading_token)
+        }
     }
 
-    /// Parses a lifetime ("outlives") bound, e.g. `'a`, according to:
+    /// Parse a lifetime-bound aka outlives-bound.
+    ///
     /// ```ebnf
-    /// LT_BOUND = LIFETIME
+    /// LifetimeBound = Lifetime
     /// ```
-    fn parse_generic_lt_bound(
-        &mut self,
-        lo: Span,
-        parens: ast::Parens,
-    ) -> PResult<'a, GenericBound> {
+    fn parse_lifetime_bound(&mut self, lo: Span, parens: ast::Parens) -> PResult<'a, GenericBound> {
         let lt = self.expect_lifetime();
-        let bound = GenericBound::Outlives(lt);
+
         if let ast::Parens::Yes = parens {
-            // FIXME(Centril): Consider not erroring here and accepting `('lt)` instead,
-            // possibly introducing `GenericBound::Paren(Box<GenericBound>)`?
-            self.recover_paren_lifetime(lo)?;
+            self.expect(exp!(CloseParen))?;
+            self.report_parenthesized_bound(lo, self.prev_token.span, "lifetime bounds");
         }
-        Ok(bound)
+
+        Ok(GenericBound::Outlives(lt))
+    }
+
+    fn report_parenthesized_bound(&self, lo: Span, hi: Span, kind: &str) -> ErrorGuaranteed {
+        let mut diag =
+            self.dcx().struct_span_err(lo.to(hi), format!("{kind} may not be parenthesized"));
+        diag.multipart_suggestion(
+            "remove the parentheses",
+            vec![(lo, String::new()), (hi, String::new())],
+            Applicability::MachineApplicable,
+        );
+        diag.emit()
     }
 
     /// Emits an error if any trait bound modifiers were present.
@@ -1074,27 +1115,17 @@ impl<'a> Parser<'a> {
         unreachable!("lifetime bound intercepted in `parse_generic_ty_bound` but no modifiers?")
     }
 
-    /// Recover on `('lifetime)` with `(` already eaten.
-    fn recover_paren_lifetime(&mut self, lo: Span) -> PResult<'a, ()> {
-        self.expect(exp!(CloseParen))?;
-        let span = lo.to(self.prev_token.span);
-        let sugg = errors::RemoveParens { lo, hi: self.prev_token.span };
-
-        self.dcx().emit_err(errors::ParenthesizedLifetime { span, sugg });
-        Ok(())
-    }
-
     /// Parses the modifiers that may precede a trait in a bound, e.g. `?Trait` or `[const] Trait`.
     ///
     /// If no modifiers are present, this does not consume any tokens.
     ///
     /// ```ebnf
-    /// CONSTNESS = [["["] "const" ["]"]]
-    /// ASYNCNESS = ["async"]
-    /// POLARITY = ["?" | "!"]
+    /// Constness = ("const" | "[" "const" "]")?
+    /// Asyncness = "async"?
+    /// Polarity = ("?" | "!")?
     /// ```
     ///
-    /// See `parse_generic_ty_bound` for the complete grammar of trait bound modifiers.
+    /// See `parse_trait_bound` for more context.
     fn parse_trait_bound_modifiers(&mut self) -> PResult<'a, TraitBoundModifiers> {
         let modifier_lo = self.token.span;
         let constness = self.parse_bound_constness()?;
@@ -1187,20 +1218,21 @@ impl<'a> Parser<'a> {
         })
     }
 
-    /// Parses a type bound according to:
+    /// Parse a trait bound.
+    ///
     /// ```ebnf
-    /// TY_BOUND = TY_BOUND_NOPAREN | (TY_BOUND_NOPAREN)
-    /// TY_BOUND_NOPAREN = [for<GENERIC_PARAMS> CONSTNESS ASYNCNESS | POLARITY] SIMPLE_PATH
+    /// TraitBound = BareTraitBound | "(" BareTraitBound ")"
+    /// BareTraitBound =
+    ///     (HigherRankedBinder Constness Asyncness | Polarity)
+    ///     TypePath
     /// ```
-    ///
-    /// For example, this grammar accepts `for<'a: 'b> [const] ?m::Trait<'a>`.
-    fn parse_generic_ty_bound(
+    fn parse_trait_bound(
         &mut self,
         lo: Span,
         parens: ast::Parens,
         leading_token: &Token,
     ) -> PResult<'a, GenericBound> {
-        let (mut lifetime_defs, binder_span) = self.parse_late_bound_lifetime_defs()?;
+        let (mut bound_vars, binder_span) = self.parse_higher_ranked_binder()?;
 
         let modifiers_lo = self.token.span;
         let modifiers = self.parse_trait_bound_modifiers()?;
@@ -1223,11 +1255,11 @@ impl<'a> Parser<'a> {
         // e.g. `T: for<'a> 'a` or `T: [const] 'a`.
         if self.token.is_lifetime() {
             let _: ErrorGuaranteed = self.error_lt_bound_with_modifiers(modifiers, binder_span);
-            return self.parse_generic_lt_bound(lo, parens);
+            return self.parse_lifetime_bound(lo, parens);
         }
 
-        if let (more_lifetime_defs, Some(binder_span)) = self.parse_late_bound_lifetime_defs()? {
-            lifetime_defs.extend(more_lifetime_defs);
+        if let (more_bound_vars, Some(binder_span)) = self.parse_higher_ranked_binder()? {
+            bound_vars.extend(more_bound_vars);
             self.dcx().emit_err(errors::BinderBeforeModifiers { binder_span, modifiers_span });
         }
 
@@ -1287,7 +1319,7 @@ impl<'a> Parser<'a> {
         };
 
         if self.may_recover() && self.token == TokenKind::OpenParen {
-            self.recover_fn_trait_with_lifetime_params(&mut path, &mut lifetime_defs)?;
+            self.recover_fn_trait_with_lifetime_params(&mut path, &mut bound_vars)?;
         }
 
         if let ast::Parens::Yes = parens {
@@ -1310,7 +1342,7 @@ impl<'a> Parser<'a> {
         }
 
         let poly_trait =
-            PolyTraitRef::new(lifetime_defs, path, modifiers, lo.to(self.prev_token.span), parens);
+            PolyTraitRef::new(bound_vars, path, modifiers, lo.to(self.prev_token.span), parens);
         Ok(GenericBound::Trait(poly_trait))
     }
 
@@ -1349,8 +1381,12 @@ impl<'a> Parser<'a> {
         }
     }
 
-    /// Optionally parses `for<$generic_params>`.
-    pub(super) fn parse_late_bound_lifetime_defs(
+    /// Parse an optional higher-ranked binder.
+    ///
+    /// ```ebnf
+    /// HigherRankedBinder = ("for" "<" GenericParams ">")?
+    /// ```
+    pub(super) fn parse_higher_ranked_binder(
         &mut self,
     ) -> PResult<'a, (ThinVec<GenericParam>, Option<Span>)> {
         if self.eat_keyword(exp!(For)) {
@@ -1466,8 +1502,7 @@ impl<'a> Parser<'a> {
     pub(super) fn expect_lifetime(&mut self) -> Lifetime {
         if let Some((ident, is_raw)) = self.token.lifetime() {
             if matches!(is_raw, IdentIsRaw::No)
-                && ident.without_first_quote().is_reserved()
-                && ![kw::UnderscoreLifetime, kw::StaticLifetime].contains(&ident.name)
+                && ident.without_first_quote().is_reserved_lifetime()
             {
                 self.dcx().emit_err(errors::KeywordLifetime { span: ident.span });
             }