X-Git-Url: https://git.lizzy.rs/?a=blobdiff_plain;f=compiler%2Frustc_ast_lowering%2Fsrc%2Fpath.rs;h=592fc5aa6456f064e0d399f5a0c1487067f147ce;hb=d429e463c19fc45d70343779eef5b0b8f7231c70;hp=8d23c26e603b77bf035aded708af0676d47dff59;hpb=4fdc3eb1761ee50961e4da67b7ccda9d971f5f20;p=rust.git

diff --git a/compiler/rustc_ast_lowering/src/path.rs b/compiler/rustc_ast_lowering/src/path.rs
index 8d23c26e603..592fc5aa645 100644
--- a/compiler/rustc_ast_lowering/src/path.rs
+++ b/compiler/rustc_ast_lowering/src/path.rs
@@ -9,7 +9,7 @@
 use rustc_hir as hir;
 use rustc_hir::def::{DefKind, PartialRes, Res};
 use rustc_hir::GenericArg;
-use rustc_span::symbol::{kw, Ident};
+use rustc_span::symbol::{kw, sym, Ident};
 use rustc_span::{BytePos, Span, DUMMY_SP};
 
 use smallvec::{smallvec, SmallVec};
@@ -352,11 +352,18 @@ fn lower_parenthesized_parameter_data(
             // fn f(_: impl Fn() -> impl Debug) -> impl Fn() -> impl Debug
             // //      disallowed --^^^^^^^^^^        allowed --^^^^^^^^^^
             // ```
-            FnRetTy::Ty(ty)
-                if matches!(itctx, ImplTraitContext::ReturnPositionOpaqueTy { .. })
-                    && self.tcx.features().impl_trait_in_fn_trait_return =>
-            {
-                self.lower_ty(&ty, itctx)
+            FnRetTy::Ty(ty) if matches!(itctx, ImplTraitContext::ReturnPositionOpaqueTy { .. }) => {
+                if self.tcx.features().impl_trait_in_fn_trait_return {
+                    self.lower_ty(&ty, itctx)
+                } else {
+                    self.lower_ty(
+                        &ty,
+                        &ImplTraitContext::FeatureGated(
+                            ImplTraitPosition::FnTraitReturn,
+                            sym::impl_trait_in_fn_trait_return,
+                        ),
+                    )
+                }
             }
             FnRetTy::Ty(ty) => {
                 self.lower_ty(&ty, &ImplTraitContext::Disallowed(ImplTraitPosition::FnTraitReturn))