Remove unused/unnecessary features

compiler/rustc_ast/src/lib.rs

@@ -13,13 +13,11 @@
 #![feature(rustdoc_internals)]
 #![feature(associated_type_bounds)]
 #![feature(box_patterns)]
-#![feature(const_trait_impl)]
 #![feature(if_let_guard)]
 #![feature(let_chains)]
 #![feature(min_specialization)]
 #![feature(negative_impls)]
 #![feature(stmt_expr_attributes)]
-#![recursion_limit = "256"]
 #![deny(rustc::untranslatable_diagnostic)]
 #![deny(rustc::diagnostic_outside_of_impl)]
 

compiler/rustc_ast_lowering/src/lib.rs

@@ -33,10 +33,8 @@
 #![allow(internal_features)]
 #![feature(rustdoc_internals)]
 #![doc(rust_logo)]
-#![feature(if_let_guard)]
 #![feature(box_patterns)]
 #![feature(let_chains)]
-#![recursion_limit = "256"]
 #![deny(rustc::untranslatable_diagnostic)]
 #![deny(rustc::diagnostic_outside_of_impl)]
 

compiler/rustc_ast_passes/src/lib.rs

@@ -11,7 +11,6 @@
 #![feature(if_let_guard)]
 #![feature(iter_is_partitioned)]
 #![feature(let_chains)]
-#![recursion_limit = "256"]
 #![deny(rustc::untranslatable_diagnostic)]
 #![deny(rustc::diagnostic_outside_of_impl)]
 

compiler/rustc_ast_pretty/src/lib.rs

@@ -4,8 +4,6 @@
 #![deny(rustc::untranslatable_diagnostic)]
 #![deny(rustc::diagnostic_outside_of_impl)]
 #![feature(box_patterns)]
-#![feature(let_chains)]
-#![recursion_limit = "256"]
 
 mod helpers;
 pub mod pp;

compiler/rustc_borrowck/src/lib.rs

@@ -8,12 +8,9 @@
 #![feature(let_chains)]
 #![feature(min_specialization)]
 #![feature(never_type)]
-#![feature(lazy_cell)]
 #![feature(rustc_attrs)]
 #![feature(stmt_expr_attributes)]
-#![feature(trusted_step)]
 #![feature(try_blocks)]
-#![recursion_limit = "256"]
 
 #[macro_use]
 extern crate rustc_middle;

compiler/rustc_builtin_macros/src/lib.rs

@@ -5,17 +5,14 @@
 #![feature(rustdoc_internals)]
 #![doc(rust_logo)]
 #![doc(html_root_url = "https://doc.rust-lang.org/nightly/nightly-rustc/")]
-#![feature(array_windows)]
 #![feature(assert_matches)]
 #![feature(box_patterns)]
 #![feature(decl_macro)]
 #![feature(if_let_guard)]
-#![feature(is_sorted)]
 #![feature(let_chains)]
 #![feature(lint_reasons)]
 #![feature(proc_macro_internals)]
 #![feature(proc_macro_quote)]
-#![recursion_limit = "256"]
 
 extern crate proc_macro;
 

compiler/rustc_codegen_llvm/src/lib.rs

@@ -14,9 +14,7 @@
 #![feature(iter_intersperse)]
 #![feature(let_chains)]
 #![feature(min_specialization)]
-#![feature(never_type)]
 #![feature(impl_trait_in_assoc_type)]
-#![recursion_limit = "256"]
 #![deny(rustc::untranslatable_diagnostic)]
 #![deny(rustc::diagnostic_outside_of_impl)]
 

compiler/rustc_codegen_ssa/src/lib.rs

@@ -7,10 +7,8 @@
 #![feature(if_let_guard)]
 #![feature(let_chains)]
 #![feature(negative_impls)]
-#![feature(never_type)]
 #![feature(strict_provenance)]
 #![feature(try_blocks)]
-#![recursion_limit = "256"]
 
 //! This crate contains codegen code that is used by all codegen backends (LLVM and others).
 //! The backend-agnostic functions of this crate use functions defined in various traits that

compiler/rustc_const_eval/src/lib.rs

@@ -11,20 +11,13 @@ Rust MIR: a lowered representation of Rust.
 #![feature(assert_matches)]
 #![feature(box_patterns)]
 #![feature(decl_macro)]
-#![feature(exact_size_is_empty)]
 #![feature(let_chains)]
-#![feature(map_try_insert)]
-#![feature(min_specialization)]
 #![feature(slice_ptr_get)]
-#![feature(option_get_or_insert_default)]
 #![feature(never_type)]
 #![feature(trait_alias)]
-#![feature(trusted_len)]
-#![feature(trusted_step)]
 #![feature(try_blocks)]
 #![feature(yeet_expr)]
 #![feature(if_let_guard)]
-#![recursion_limit = "256"]
 
 #[macro_use]
 extern crate tracing;

compiler/rustc_data_structures/src/lib.rs

@@ -10,6 +10,7 @@
 #![allow(internal_features)]
 #![allow(rustc::default_hash_types)]
 #![allow(rustc::potential_query_instability)]
+#![cfg_attr(not(parallel_compiler), feature(cell_leak))]
 #![deny(rustc::diagnostic_outside_of_impl)]
 #![deny(rustc::untranslatable_diagnostic)]
 #![deny(unsafe_op_in_unsafe_fn)]
@@ -18,7 +19,6 @@
 #![feature(allocator_api)]
 #![feature(array_windows)]
 #![feature(auto_traits)]
-#![feature(cell_leak)]
 #![feature(cfg_match)]
 #![feature(core_intrinsics)]
 #![feature(extend_one)]

compiler/rustc_driver_impl/src/lib.rs

@@ -9,11 +9,9 @@
 #![feature(rustdoc_internals)]
 #![allow(internal_features)]
 #![feature(decl_macro)]
-#![feature(lazy_cell)]
 #![feature(let_chains)]
 #![feature(panic_update_hook)]
 #![feature(result_flattening)]
-#![recursion_limit = "256"]
 #![deny(rustc::untranslatable_diagnostic)]
 #![deny(rustc::diagnostic_outside_of_impl)]
 

compiler/rustc_error_messages/src/lib.rs

@@ -1,6 +1,5 @@
 #![doc(rust_logo)]
 #![feature(rustdoc_internals)]
-#![feature(let_chains)]
 #![feature(lazy_cell)]
 #![feature(rustc_attrs)]
 #![feature(type_alias_impl_trait)]

compiler/rustc_errors/src/lib.rs

@@ -8,15 +8,14 @@
 #![feature(array_windows)]
 #![feature(associated_type_defaults)]
 #![feature(box_into_inner)]
+#![feature(box_patterns)]
 #![feature(extract_if)]
-#![feature(if_let_guard)]
 #![feature(let_chains)]
 #![feature(negative_impls)]
 #![feature(never_type)]
 #![feature(rustc_attrs)]
 #![feature(yeet_expr)]
 #![feature(try_blocks)]
-#![feature(box_patterns)]
 #![feature(error_reporter)]
 #![allow(incomplete_features)]
 #![allow(internal_features)]

compiler/rustc_expand/src/lib.rs

@@ -9,9 +9,7 @@
 #![feature(proc_macro_diagnostic)]
 #![feature(proc_macro_internals)]
 #![feature(proc_macro_span)]
-#![feature(rustc_attrs)]
 #![feature(try_blocks)]
-#![recursion_limit = "256"]
 #![deny(rustc::untranslatable_diagnostic)]
 #![allow(internal_features)]
 

compiler/rustc_hir/src/lib.rs

@@ -9,7 +9,6 @@
 #![feature(never_type)]
 #![feature(rustc_attrs)]
 #![feature(variant_count)]
-#![recursion_limit = "256"]
 #![deny(rustc::untranslatable_diagnostic)]
 #![deny(rustc::diagnostic_outside_of_impl)]
 #![allow(internal_features)]

compiler/rustc_hir_analysis/src/lib.rs

@@ -60,7 +60,6 @@ This API is completely unstable and subject to change.
 #![doc(rust_logo)]
 #![feature(rustdoc_internals)]
 #![allow(internal_features)]
-#![feature(box_patterns)]
 #![feature(control_flow_enum)]
 #![feature(if_let_guard)]
 #![feature(is_sorted)]
@@ -71,8 +70,6 @@ This API is completely unstable and subject to change.
 #![feature(lazy_cell)]
 #![feature(slice_partition_dedup)]
 #![feature(try_blocks)]
-#![feature(type_alias_impl_trait)]
-#![recursion_limit = "256"]
 
 #[macro_use]
 extern crate tracing;

compiler/rustc_hir_typeck/src/check.rs

@@ -72,7 +72,7 @@ pub(super) fn check_fn<'a, 'tcx>(
     let inputs_fn = fn_sig.inputs().iter().copied();
     for (idx, (param_ty, param)) in inputs_fn.chain(maybe_va_list).zip(body.params).enumerate() {
         // Check the pattern.
-        let ty: Option<&hir::Ty<'_>> = try { inputs_hir?.get(idx)? };
+        let ty: Option<&hir::Ty<'_>> = inputs_hir.and_then(|h| h.get(idx));
         let ty_span = ty.map(|ty| ty.span);
         fcx.check_pat_top(param.pat, param_ty, ty_span, None, None);
         if param.pat.is_never_pattern() {

compiler/rustc_hir_typeck/src/lib.rs

@@ -5,7 +5,6 @@
 #![feature(box_patterns)]
 #![feature(min_specialization)]
 #![feature(control_flow_enum)]
-#![recursion_limit = "256"]
 
 #[macro_use]
 extern crate tracing;

compiler/rustc_incremental/src/lib.rs

@@ -5,7 +5,6 @@
 #![doc(rust_logo)]
 #![feature(rustdoc_internals)]
 #![allow(internal_features)]
-#![recursion_limit = "256"]
 #![deny(rustc::untranslatable_diagnostic)]
 #![deny(rustc::diagnostic_outside_of_impl)]
 

compiler/rustc_index/src/lib.rs

@@ -2,16 +2,9 @@
 #![deny(rustc::diagnostic_outside_of_impl)]
 #![cfg_attr(
     feature = "nightly",
-    feature(
-        allow_internal_unstable,
-        extend_one,
-        min_specialization,
-        new_uninit,
-        step_trait,
-        stmt_expr_attributes,
-        test
-    )
+    feature(extend_one, min_specialization, new_uninit, step_trait, test)
 )]
+#![cfg_attr(all(feature = "nightly", test), feature(stmt_expr_attributes))]
 #![cfg_attr(feature = "nightly", allow(internal_features))]
 
 pub mod bit_set;

compiler/rustc_infer/src/lib.rs

@@ -18,12 +18,10 @@
 #![allow(internal_features)]
 #![feature(associated_type_bounds)]
 #![feature(box_patterns)]
-#![feature(control_flow_enum)]
 #![feature(extend_one)]
 #![feature(let_chains)]
 #![feature(if_let_guard)]
 #![feature(min_specialization)]
-#![feature(never_type)]
 #![feature(try_blocks)]
 #![recursion_limit = "512"] // For rustdoc
 

compiler/rustc_interface/src/lib.rs

@@ -1,12 +1,9 @@
-#![feature(box_patterns)]
 #![feature(decl_macro)]
 #![feature(error_iter)]
-#![feature(internal_output_capture)]
 #![feature(lazy_cell)]
 #![feature(let_chains)]
 #![feature(thread_spawn_unchecked)]
 #![feature(try_blocks)]
-#![recursion_limit = "256"]
 #![deny(rustc::untranslatable_diagnostic)]
 #![deny(rustc::diagnostic_outside_of_impl)]
 

compiler/rustc_lint/src/lib.rs

@@ -32,14 +32,11 @@
 #![feature(box_patterns)]
 #![feature(control_flow_enum)]
 #![feature(if_let_guard)]
-#![feature(iter_intersperse)]
 #![feature(iter_order_by)]
 #![feature(let_chains)]
 #![cfg_attr(not(bootstrap), feature(trait_upcasting))]
 #![feature(min_specialization)]
-#![feature(never_type)]
 #![feature(rustc_attrs)]
-#![recursion_limit = "256"]
 #![deny(rustc::untranslatable_diagnostic)]
 #![deny(rustc::diagnostic_outside_of_impl)]
 #![allow(internal_features)]

compiler/rustc_macros/src/lib.rs

@@ -9,7 +9,6 @@
 #![deny(rustc::untranslatable_diagnostic)]
 #![deny(rustc::diagnostic_outside_of_impl)]
 #![allow(internal_features)]
-#![recursion_limit = "128"]
 
 use synstructure::decl_derive;
 

compiler/rustc_metadata/src/lib.rs

@@ -11,11 +11,9 @@
 #![feature(proc_macro_internals)]
 #![feature(macro_metavar_expr)]
 #![feature(min_specialization)]
-#![feature(slice_as_chunks)]
 #![feature(trusted_len)]
 #![feature(try_blocks)]
 #![feature(never_type)]
-#![recursion_limit = "256"]
 #![allow(rustc::potential_query_instability)]
 #![deny(rustc::untranslatable_diagnostic)]
 #![deny(rustc::diagnostic_outside_of_impl)]

compiler/rustc_middle/src/lib.rs

@@ -33,7 +33,6 @@
 #![feature(discriminant_kind)]
 #![feature(exhaustive_patterns)]
 #![feature(coroutines)]
-#![feature(get_mut_unchecked)]
 #![feature(if_let_guard)]
 #![feature(inline_const)]
 #![feature(iter_from_coroutine)]
@@ -50,19 +49,14 @@
 #![feature(rustc_attrs)]
 #![feature(control_flow_enum)]
 #![cfg_attr(not(bootstrap), feature(trait_upcasting))]
-#![feature(trusted_step)]
 #![feature(try_blocks)]
-#![feature(try_reserve_kind)]
-#![feature(nonzero_ops)]
 #![feature(decl_macro)]
 #![feature(extract_if)]
 #![feature(intra_doc_pointers)]
 #![feature(yeet_expr)]
 #![feature(const_option)]
-#![feature(trait_alias)]
 #![feature(ptr_alignment_type)]
 #![feature(macro_metavar_expr)]
-#![recursion_limit = "512"]
 #![allow(rustc::potential_query_instability)]
 #![allow(internal_features)]
 

compiler/rustc_mir_build/src/lib.rs

@@ -8,7 +8,6 @@
 #![feature(let_chains)]
 #![feature(min_specialization)]
 #![feature(try_blocks)]
-#![recursion_limit = "256"]
 
 #[macro_use]
 extern crate tracing;

compiler/rustc_mir_dataflow/src/framework/cursor.rs

@@ -185,8 +185,8 @@ where
         debug_assert_eq!(target.block, self.pos.block);
 
         let block_data = &self.body[target.block];
+        #[rustfmt::skip]
         let next_effect = if A::Direction::IS_FORWARD {
-            #[rustfmt::skip]
             self.pos.curr_effect_index.map_or_else(
                 || Effect::Before.at_index(0),
                 EffectIndex::next_in_forward_order,

compiler/rustc_mir_dataflow/src/lib.rs

@@ -3,9 +3,7 @@
 #![feature(exact_size_is_empty)]
 #![feature(let_chains)]
 #![feature(min_specialization)]
-#![feature(stmt_expr_attributes)]
 #![feature(try_blocks)]
-#![recursion_limit = "256"]
 #![deny(rustc::untranslatable_diagnostic)]
 #![deny(rustc::diagnostic_outside_of_impl)]
 

compiler/rustc_mir_transform/src/lib.rs

@@ -14,11 +14,9 @@
 #![feature(never_type)]
 #![feature(option_get_or_insert_default)]
 #![feature(round_char_boundary)]
-#![feature(trusted_step)]
 #![feature(try_blocks)]
 #![feature(yeet_expr)]
 #![feature(if_let_guard)]
-#![recursion_limit = "256"]
 
 #[macro_use]
 extern crate tracing;

compiler/rustc_monomorphize/src/lib.rs

@@ -1,6 +1,5 @@
 #![feature(array_windows)]
 #![feature(is_sorted)]
-#![recursion_limit = "256"]
 #![allow(rustc::potential_query_instability)]
 #![deny(rustc::untranslatable_diagnostic)]
 #![deny(rustc::diagnostic_outside_of_impl)]

compiler/rustc_parse/src/lib.rs

@@ -5,9 +5,6 @@
 #![feature(if_let_guard)]
 #![feature(iter_intersperse)]
 #![feature(let_chains)]
-#![feature(never_type)]
-#![feature(rustc_attrs)]
-#![recursion_limit = "256"]
 #![allow(internal_features)]
 
 #[macro_use]

compiler/rustc_passes/src/lib.rs

@@ -8,13 +8,11 @@
 #![doc(rust_logo)]
 #![feature(rustdoc_internals)]
 #![allow(internal_features)]
-#![feature(iter_intersperse)]
 #![feature(let_chains)]
 #![feature(map_try_insert)]
 #![feature(min_specialization)]
 #![feature(slice_group_by)]
 #![feature(try_blocks)]
-#![recursion_limit = "256"]
 #![deny(rustc::untranslatable_diagnostic)]
 #![deny(rustc::diagnostic_outside_of_impl)]
 

compiler/rustc_privacy/src/lib.rs

@@ -3,10 +3,8 @@
 #![feature(rustdoc_internals)]
 #![allow(internal_features)]
 #![feature(associated_type_defaults)]
-#![feature(rustc_private)]
 #![feature(try_blocks)]
 #![feature(let_chains)]
-#![recursion_limit = "256"]
 #![deny(rustc::untranslatable_diagnostic)]
 #![deny(rustc::diagnostic_outside_of_impl)]
 

compiler/rustc_query_impl/src/lib.rs

@@ -4,9 +4,7 @@
 #![doc(rust_logo)]
 #![feature(rustdoc_internals)]
 #![feature(min_specialization)]
-#![feature(never_type)]
 #![feature(rustc_attrs)]
-#![recursion_limit = "256"]
 #![allow(rustc::potential_query_instability, unused_parens)]
 #![deny(rustc::untranslatable_diagnostic)]
 #![deny(rustc::diagnostic_outside_of_impl)]

compiler/rustc_resolve/src/lib.rs

@@ -15,9 +15,7 @@
 #![feature(if_let_guard)]
 #![feature(iter_intersperse)]
 #![feature(let_chains)]
-#![feature(never_type)]
 #![feature(rustc_attrs)]
-#![recursion_limit = "256"]
 #![allow(rustdoc::private_intra_doc_links)]
 #![allow(rustc::potential_query_instability)]
 #![allow(internal_features)]

compiler/rustc_serialize/src/lib.rs

@@ -8,7 +8,6 @@
 #![doc(rust_logo)]
 #![allow(internal_features)]
 #![feature(rustdoc_internals)]
-#![feature(allocator_api)]
 #![feature(associated_type_bounds)]
 #![feature(const_option)]
 #![feature(core_intrinsics)]

compiler/rustc_session/src/lib.rs

@@ -1,11 +1,9 @@
 #![feature(let_chains)]
-#![feature(never_type)]
 #![feature(lazy_cell)]
 #![feature(option_get_or_insert_default)]
 #![feature(rustc_attrs)]
 #![feature(map_many_mut)]
 #![feature(iter_intersperse)]
-#![recursion_limit = "256"]
 #![deny(rustc::untranslatable_diagnostic)]
 #![deny(rustc::diagnostic_outside_of_impl)]
 #![allow(internal_features)]

compiler/rustc_symbol_mangling/src/lib.rs

@@ -91,8 +91,6 @@
 #![doc(rust_logo)]
 #![feature(rustdoc_internals)]
 #![allow(internal_features)]
-#![feature(never_type)]
-#![recursion_limit = "256"]
 #![deny(rustc::untranslatable_diagnostic)]
 #![deny(rustc::diagnostic_outside_of_impl)]
 

compiler/rustc_target/src/lib.rs

@@ -11,12 +11,10 @@
 #![doc(rust_logo)]
 #![feature(rustdoc_internals)]
 #![feature(assert_matches)]
-#![feature(associated_type_bounds)]
 #![feature(exhaustive_patterns)]
 #![feature(iter_intersperse)]
 #![feature(let_chains)]
 #![feature(min_specialization)]
-#![feature(never_type)]
 #![feature(rustc_attrs)]
 #![feature(step_trait)]
 #![deny(rustc::untranslatable_diagnostic)]

compiler/rustc_trait_selection/src/lib.rs

@@ -20,7 +20,6 @@
 #![feature(extract_if)]
 #![feature(let_chains)]
 #![feature(option_take_if)]
-#![feature(if_let_guard)]
 #![feature(never_type)]
 #![feature(type_alias_impl_trait)]
 #![feature(min_specialization)]

compiler/rustc_traits/src/lib.rs

@@ -2,7 +2,6 @@
 
 #![deny(rustc::untranslatable_diagnostic)]
 #![deny(rustc::diagnostic_outside_of_impl)]
-#![feature(let_chains)]
 #![recursion_limit = "256"]
 
 #[macro_use]

compiler/rustc_transmute/src/lib.rs

@@ -1,4 +1,5 @@
-#![feature(alloc_layout_extra, decl_macro, iterator_try_reduce, never_type)]
+#![feature(alloc_layout_extra)]
+#![feature(never_type)]
 #![allow(dead_code, unused_variables)]
 #![deny(rustc::untranslatable_diagnostic)]
 #![deny(rustc::diagnostic_outside_of_impl)]

compiler/rustc_ty_utils/src/lib.rs

@@ -15,7 +15,6 @@
 #![feature(iterator_try_collect)]
 #![feature(let_chains)]
 #![feature(never_type)]
-#![recursion_limit = "256"]
 #![deny(rustc::untranslatable_diagnostic)]
 #![deny(rustc::diagnostic_outside_of_impl)]
 

compiler/stable_mir/src/lib.rs

@@ -16,7 +16,6 @@
 //!
 //! The goal is to eventually be published on
 //! [crates.io](https://crates.io).
-#![feature(type_alias_impl_trait)]
 #[macro_use]
 extern crate scoped_tls;