2 files changed, 21 insertions, 2 deletions
diff --git a/compiler/rustc_span/src/hygiene.rs b/compiler/rustc_span/src/hygiene.rs
index d1da68ec236..53908914965 100644
--- a/compiler/rustc_span/src/hygiene.rs
+++ b/compiler/rustc_span/src/hygiene.rs
@@ -1232,6 +1232,25 @@ impl DesugaringKind {
             DesugaringKind::PatTyRange => "pattern type",
         }
     }
+
+    /// For use with `rustc_unimplemented` to support conditions
+    /// like `from_desugaring = "QuestionMark"`
+    pub fn matches(&self, value: &str) -> bool {
+        match self {
+            DesugaringKind::CondTemporary => value == "CondTemporary",
+            DesugaringKind::Async => value == "Async",
+            DesugaringKind::Await => value == "Await",
+            DesugaringKind::QuestionMark => value == "QuestionMark",
+            DesugaringKind::TryBlock => value == "TryBlock",
+            DesugaringKind::YeetExpr => value == "YeetExpr",
+            DesugaringKind::OpaqueTy => value == "OpaqueTy",
+            DesugaringKind::ForLoop => value == "ForLoop",
+            DesugaringKind::WhileLoop => value == "WhileLoop",
+            DesugaringKind::BoundModifier => value == "BoundModifier",
+            DesugaringKind::Contract => value == "Contract",
+            DesugaringKind::PatTyRange => value == "PatTyRange",
+        }
+    }
 }
 
 #[derive(Default)]
diff --git a/compiler/rustc_span/src/symbol.rs b/compiler/rustc_span/src/symbol.rs
index 8f75cc5e5e6..32a5aff0cb3 100644
--- a/compiler/rustc_span/src/symbol.rs
+++ b/compiler/rustc_span/src/symbol.rs
@@ -372,6 +372,7 @@ symbols! {
         SyncUnsafeCell,
         T,
         Target,
+        This,
         ToOwned,
         ToString,
         TokenStream,
@@ -1186,6 +1187,7 @@ symbols! {
         instruction_set,
         integer_: "integer", // underscore to avoid clashing with the function `sym::integer` below
         integral,
+        internal_features,
         into_async_iter_into_iter,
         into_future,
         into_iter,
@@ -1822,7 +1824,6 @@ symbols! {
         rustc_lint_opt_ty,
         rustc_lint_query_instability,
         rustc_lint_untracked_query_information,
-        rustc_macro_edition_2021,
         rustc_macro_transparency,
         rustc_main,
         rustc_mir,
@@ -2216,7 +2217,6 @@ symbols! {
         unsafe_extern_blocks,
         unsafe_fields,
         unsafe_no_drop_flag,
-        unsafe_pin_internals,
         unsafe_pinned,
         unsafe_unpin,
         unsize,