Remove some unused features from alloc core and std

library/alloc/src/lib.rs

@@ -74,6 +74,7 @@
 #![deny(unsafe_op_in_unsafe_fn)]
 #![cfg_attr(not(test), feature(generator_trait))]
 #![cfg_attr(test, feature(test))]
+#![cfg_attr(test, feature(new_uninit))]
 #![feature(allocator_api)]
 #![feature(array_chunks)]
 #![feature(array_windows)]
@@ -81,7 +82,6 @@
 #![feature(arbitrary_self_types)]
 #![feature(box_patterns)]
 #![feature(box_syntax)]
-#![feature(btree_drain_filter)]
 #![feature(cfg_sanitize)]
 #![feature(cfg_target_has_atomic)]
 #![feature(coerce_unsized)]
@@ -89,10 +89,8 @@
 #![feature(const_generics)]
 #![feature(const_in_array_repeat_expressions)]
 #![feature(cow_is_borrowed)]
-#![feature(deque_range)]
 #![feature(dispatch_from_dyn)]
 #![feature(core_intrinsics)]
-#![feature(container_error_extra)]
 #![feature(dropck_eyepatch)]
 #![feature(exact_size_is_empty)]
 #![feature(exclusive_range_pattern)]
@@ -103,12 +101,9 @@
 #![feature(inplace_iteration)]
 #![feature(lang_items)]
 #![feature(layout_for_ptr)]
-#![feature(map_first_last)]
-#![feature(map_into_keys_values)]
 #![feature(maybe_uninit_ref)]
 #![feature(negative_impls)]
 #![feature(never_type)]
-#![feature(new_uninit)]
 #![feature(nll)]
 #![feature(nonnull_slice_from_raw_parts)]
 #![feature(optin_builtin_traits)]
@@ -123,10 +118,8 @@
 #![feature(slice_ptr_get)]
 #![feature(slice_ptr_len)]
 #![feature(staged_api)]
-#![feature(std_internals)]
 #![feature(str_internals)]
 #![feature(trusted_len)]
-#![feature(try_reserve)]
 #![feature(unboxed_closures)]
 #![feature(unicode_internals)]
 #![feature(unsafe_block_in_unsafe_fn)]