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)]
 

compiler/rustc_feature/src/accepted.rs

@@ -197,6 +197,8 @@ declare_features! (
     /// + `impl<I:Iterator> Iterator for &mut Iterator`
     /// + `impl Debug for Foo<'_>`
     (accepted, impl_header_lifetime_elision, "1.31.0", Some(15872)),
+    /// Allows `impl Trait` to be used inside associated types (RFC 2515).
+    (accepted, impl_trait_in_assoc_type, "CURRENT_RUSTC_VERSION", Some(63063)),
     /// Allows referencing `Self` and projections in impl-trait.
     (accepted, impl_trait_projections, "1.74.0", Some(103532)),
     /// Allows using `a..=b` and `..=b` as inclusive range syntaxes.

compiler/rustc_feature/src/unstable.rs

@@ -485,8 +485,6 @@ declare_features! (
     (unstable, half_open_range_patterns_in_slices, "1.66.0", Some(67264)),
     /// Allows `if let` guard in match arms.
     (unstable, if_let_guard, "1.47.0", Some(51114)),
-    /// Allows `impl Trait` to be used inside associated types (RFC 2515).
-    (unstable, impl_trait_in_assoc_type, "1.70.0", Some(63063)),
     /// Allows `impl Trait` as output type in `Fn` traits in return position of functions.
     (unstable, impl_trait_in_fn_trait_return, "1.64.0", Some(99697)),
     /// Allows using imported `main` function

compiler/rustc_mir_transform/src/lib.rs

@@ -5,7 +5,7 @@
 #![feature(const_type_name)]
 #![feature(cow_is_borrowed)]
 #![feature(decl_macro)]
-#![feature(impl_trait_in_assoc_type)]
+#![cfg_attr(bootstrap, feature(impl_trait_in_assoc_type))]
 #![feature(inline_const)]
 #![feature(is_sorted)]
 #![feature(let_chains)]

src/librustdoc/lib.rs

@@ -6,7 +6,6 @@
 #![feature(assert_matches)]
 #![feature(box_patterns)]
 #![feature(if_let_guard)]
-#![feature(impl_trait_in_assoc_type)]
 #![feature(iter_intersperse)]
 #![feature(lazy_cell)]
 #![feature(let_chains)]

tests/rustdoc/auxiliary/issue-73061.rs

@@ -1,7 +1,5 @@
 //edition:2018
 
-#![feature(impl_trait_in_assoc_type)]
-
 pub trait Foo {
     type X: std::future::Future<Output = ()>;
     fn x(&self) -> Self::X;

tests/ui/associated-types/issue-63591.rs

@@ -1,7 +1,6 @@
 // check-pass
 
 #![feature(associated_type_bounds)]
-#![feature(impl_trait_in_assoc_type)]
 
 fn main() {}
 

tests/ui/coroutine/issue-87142.rs

@@ -4,7 +4,7 @@
 // Regression test for #87142
 // This test needs the above flags and the "lib" crate type.
 
-#![feature(impl_trait_in_assoc_type, coroutine_trait, coroutines)]
+#![feature(coroutine_trait, coroutines)]
 #![crate_type = "lib"]
 
 use std::ops::Coroutine;