Auto merge of rust-lang#100324 - Mark-Simulacrum:bootstrap-bump, r=jyn514

Bump bootstrap compiler to 1.64

r? `@jyn514` perhaps?

Author: bors

compiler/rustc_ast/src/lib.rs

@@ -14,7 +14,6 @@
 #![feature(const_trait_impl)]
 #![feature(if_let_guard)]
 #![feature(label_break_value)]
-#![cfg_attr(bootstrap, feature(let_chains))]
 #![feature(min_specialization)]
 #![feature(negative_impls)]
 #![feature(slice_internals)]

compiler/rustc_ast_lowering/src/lib.rs

@@ -31,7 +31,6 @@
 //! in the HIR, especially for multiple identifiers.
 
 #![feature(box_patterns)]
-#![cfg_attr(bootstrap, feature(let_chains))]
 #![feature(let_else)]
 #![feature(never_type)]
 #![recursion_limit = "256"]

compiler/rustc_ast_passes/src/lib.rs

@@ -8,7 +8,6 @@
 #![feature(box_patterns)]
 #![feature(if_let_guard)]
 #![feature(iter_is_partitioned)]
-#![cfg_attr(bootstrap, feature(let_chains))]
 #![feature(let_else)]
 #![recursion_limit = "256"]
 

compiler/rustc_attr/src/lib.rs

@@ -4,7 +4,6 @@
 //! The goal is to move the definition of `MetaItem` and things that don't need to be in `syntax`
 //! to this crate.
 
-#![cfg_attr(bootstrap, feature(let_chains))]
 #![feature(let_else)]
 
 #[macro_use]

compiler/rustc_borrowck/src/lib.rs

@@ -2,7 +2,6 @@
 
 #![allow(rustc::potential_query_instability)]
 #![feature(box_patterns)]
-#![cfg_attr(bootstrap, feature(let_chains))]
 #![feature(let_else)]
 #![feature(min_specialization)]
 #![feature(never_type)]

compiler/rustc_builtin_macros/src/lib.rs

@@ -8,7 +8,6 @@
 #![feature(decl_macro)]
 #![feature(if_let_guard)]
 #![feature(is_sorted)]
-#![cfg_attr(bootstrap, feature(let_chains))]
 #![feature(let_else)]
 #![feature(proc_macro_internals)]
 #![feature(proc_macro_quote)]

compiler/rustc_codegen_llvm/src/lib.rs

@@ -6,7 +6,6 @@
 
 #![doc(html_root_url = "https://doc.rust-lang.org/nightly/nightly-rustc/")]
 #![feature(hash_raw_entry)]
-#![cfg_attr(bootstrap, feature(let_chains))]
 #![feature(let_else)]
 #![feature(extern_types)]
 #![feature(once_cell)]

compiler/rustc_const_eval/src/lib.rs

@@ -9,7 +9,6 @@ Rust MIR: a lowered representation of Rust.
 #![feature(control_flow_enum)]
 #![feature(decl_macro)]
 #![feature(exact_size_is_empty)]
-#![cfg_attr(bootstrap, feature(let_chains))]
 #![feature(let_else)]
 #![feature(map_try_insert)]
 #![feature(min_specialization)]

compiler/rustc_error_messages/src/lib.rs

@@ -1,4 +1,3 @@
-#![cfg_attr(bootstrap, feature(let_chains))]
 #![feature(once_cell)]
 #![feature(rustc_attrs)]
 #![feature(type_alias_impl_trait)]

compiler/rustc_errors/src/lib.rs

@@ -5,7 +5,6 @@
 #![doc(html_root_url = "https://doc.rust-lang.org/nightly/nightly-rustc/")]
 #![feature(drain_filter)]
 #![feature(if_let_guard)]
-#![cfg_attr(bootstrap, feature(let_chains))]
 #![feature(adt_const_params)]
 #![feature(let_else)]
 #![feature(never_type)]