Stabilize associated type position impl Trait (ATPIT)

Author: traviscross

compiler/rustc_ast_passes/src/feature_gate.rs

@@ -120,14 +120,7 @@ impl<'a> PostExpansionVisitor<'a> {
         impl Visitor<'_> for ImplTraitVisitor<'_> {
             fn visit_ty(&mut self, ty: &ast::Ty) {
                 if let ast::TyKind::ImplTrait(..) = ty.kind {
-                    if self.in_associated_ty {
-                        gate!(
-                            &self.vis,
-                            impl_trait_in_assoc_type,
-                            ty.span,
-                            "`impl Trait` in associated types is unstable"
-                        );
-                    } else {
+                    if !self.in_associated_ty {
                         gate!(
                             &self.vis,
                             type_alias_impl_trait,

compiler/rustc_codegen_llvm/src/lib.rs

@@ -14,7 +14,7 @@
 #![feature(iter_intersperse)]
 #![feature(let_chains)]
 #![feature(min_specialization)]
-#![feature(impl_trait_in_assoc_type)]
+#![cfg_attr(bootstrap, feature(impl_trait_in_assoc_type))]
 #![deny(rustc::untranslatable_diagnostic)]
 #![deny(rustc::diagnostic_outside_of_impl)]