Fix parser ICE when recovering dyn/impl after for<...>

Author: sjwang05

compiler/rustc_parse/src/parser/ty.rs

@@ -314,10 +314,23 @@ impl<'a> Parser<'a> {
                             kw: kw.as_str(),
                         },
                     });
-                    let path = self.parse_path(PathStyle::Type)?;
+                    let path = match self.parse_path(PathStyle::Type) {
+                        Ok(path) => path,
+                        Err(perr) => {
+                            err.cancel();
+                            return Err(perr);
+                        }
+                    };
                     let parse_plus = allow_plus == AllowPlus::Yes && self.check_plus();
                     let kind =
-                        self.parse_remaining_bounds_path(lifetime_defs, path, lo, parse_plus)?;
+                        match self.parse_remaining_bounds_path(lifetime_defs, path, lo, parse_plus)
+                        {
+                            Ok(kind) => kind,
+                            Err(perr) => {
+                                err.cancel();
+                                return Err(perr);
+                            }
+                        };
                     // Take the parsed bare trait object and turn it either
                     // into a `dyn` object or an `impl Trait`.
                     let kind = match (kind, kw) {

tests/ui/parser/recover-hrtb-before-dyn-impl-kw.rs

@@ -6,4 +6,8 @@ fn test(_: &for<'a> dyn Trait) {}
 fn test2(_: for<'a> impl Trait) {}
 //~^ ERROR `for<...>` expected after `impl`, not before
 
+// Issue #118564
+type A2 = dyn<for<> dyn>;
+//~^ ERROR expected identifier, found `>`
+
 fn main() {}

tests/ui/parser/recover-hrtb-before-dyn-impl-kw.stderr

@@ -22,5 +22,11 @@ LL - fn test2(_: for<'a> impl Trait) {}
 LL + fn test2(_: impl for<'a> Trait) {}
    |
 
-error: aborting due to 2 previous errors
+error: expected identifier, found `>`
+  --> $DIR/recover-hrtb-before-dyn-impl-kw.rs:10:24
+   |
+LL | type A2 = dyn<for<> dyn>;
+   |                        ^ expected identifier
+
+error: aborting due to 3 previous errors