Remove unused/unnecessary features

Author: clubby789

Diff for: 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)]
 

Diff for: 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)]
 

Diff for: 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)]
 

Diff for: 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;

Diff for: compiler/rustc_attr/src/builtin.rs

@@ -671,9 +671,7 @@ pub fn eval_condition(
                     !eval_condition(mis[0].meta_item().unwrap(), sess, features, eval)
                 }
                 sym::target => {
-                    if let Some(features) = features
-                        && !features.cfg_target_compact
-                    {
+                    if let Some(&Features { cfg_target_compact: false, .. }) = features {
                         feature_err(
                             sess,
                             sym::cfg_target_compact,

Diff for: compiler/rustc_attr/src/lib.rs

@@ -7,7 +7,6 @@
 #![allow(internal_features)]
 #![feature(rustdoc_internals)]
 #![doc(rust_logo)]
-#![feature(let_chains)]
 #![deny(rustc::untranslatable_diagnostic)]
 #![deny(rustc::diagnostic_outside_of_impl)]
 

Diff for: 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;

Diff for: compiler/rustc_builtin_macros/src/lib.rs

@@ -5,16 +5,13 @@
 #![feature(rustdoc_internals)]
 #![doc(rust_logo)]
 #![doc(html_root_url = "https://doc.rust-lang.org/nightly/nightly-rustc/")]
-#![feature(array_windows)]
 #![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;
 

Diff for: compiler/rustc_codegen_llvm/src/coverageinfo/mapgen.rs

@@ -222,7 +222,7 @@ fn encode_mappings_for_function(
     function_coverage: &FunctionCoverage<'_>,
 ) -> Vec<u8> {
     let counter_regions = function_coverage.counter_regions();
-    if counter_regions.is_empty() {
+    if counter_regions.len() == 0 {
         return Vec::new();
     }
 

Diff for: compiler/rustc_codegen_llvm/src/lib.rs

@@ -8,15 +8,12 @@
 #![feature(rustdoc_internals)]
 #![doc(rust_logo)]
 #![doc(html_root_url = "https://doc.rust-lang.org/nightly/nightly-rustc/")]
-#![feature(exact_size_is_empty)]
 #![feature(extern_types)]
 #![feature(hash_raw_entry)]
 #![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)]
 

Diff for: 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

Diff for: 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;

Diff for: compiler/rustc_data_structures/src/lib.rs

@@ -18,7 +18,6 @@
 #![feature(allocator_api)]
 #![feature(array_windows)]
 #![feature(auto_traits)]
-#![feature(cell_leak)]
 #![feature(cfg_match)]
 #![feature(core_intrinsics)]
 #![feature(extend_one)]

Diff for: compiler/rustc_driver_impl/src/lib.rs

@@ -9,11 +9,8 @@
 #![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)]
 
@@ -1249,7 +1246,7 @@ pub fn catch_fatal_errors<F: FnOnce() -> R, R>(f: F) -> Result<R, ErrorGuarantee
 /// Variant of `catch_fatal_errors` for the `interface::Result` return type
 /// that also computes the exit code.
 pub fn catch_with_exit_code(f: impl FnOnce() -> interface::Result<()>) -> i32 {
-    match catch_fatal_errors(f).flatten() {
+    match catch_fatal_errors(f).and_then(std::convert::identity) {
         Ok(()) => EXIT_SUCCESS,
         Err(_) => EXIT_FAILURE,
     }

Diff for: 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)]

Diff for: 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)]

Diff for: 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)]
 

Diff for: 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)]

Diff for: 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;

Diff for: compiler/rustc_hir_typeck/src/check.rs

@@ -73,7 +73,7 @@ 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);
 

Diff for: 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;

Diff for: 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)]
 

Diff for: 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;

Diff for: 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
 

Diff for: compiler/rustc_interface/src/lib.rs

@@ -1,11 +1,7 @@
-#![feature(box_patterns)]
 #![feature(decl_macro)]
-#![feature(internal_output_capture)]
-#![feature(thread_spawn_unchecked)]
 #![feature(lazy_cell)]
 #![feature(let_chains)]
 #![feature(try_blocks)]
-#![recursion_limit = "256"]
 #![deny(rustc::untranslatable_diagnostic)]
 #![deny(rustc::diagnostic_outside_of_impl)]
 

Diff for: compiler/rustc_lint/src/lib.rs

@@ -32,13 +32,10 @@
 #![feature(box_patterns)]
 #![feature(control_flow_enum)]
 #![feature(if_let_guard)]
-#![feature(iter_intersperse)]
 #![feature(iter_order_by)]
 #![feature(let_chains)]
 #![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)]

Diff for: 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;
 

Diff for: 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)]

Diff for: 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)]
@@ -45,23 +44,17 @@
 #![feature(min_specialization)]
 #![feature(trusted_len)]
 #![feature(type_alias_impl_trait)]
-#![feature(strict_provenance)]
 #![feature(associated_type_bounds)]
 #![feature(rustc_attrs)]
 #![feature(control_flow_enum)]
-#![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)]
 

Diff for: 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;

Diff for: 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,

Diff for: compiler/rustc_mir_dataflow/src/framework/graphviz.rs

@@ -438,8 +438,8 @@ where
         let after = next_in_dataflow_order(&mut diffs_after);
         let before = diffs_before.as_mut().map(next_in_dataflow_order);
 
-        assert!(diffs_after.is_empty());
-        assert!(diffs_before.as_ref().map_or(true, ExactSizeIterator::is_empty));
+        assert_eq!(diffs_after.len(), 0);
+        assert!(diffs_before.as_ref().map_or(true, |it| it.len() == 0));
 
         let terminator = self.results.body()[block].terminator();
         let mut terminator_str = String::new();