library/core/src/lib.rs - third_party/rust - Git at Google

 //! # The Rust Core Library
 //!
 //! The Rust Core Library is the dependency-free[^free] foundation of [The
 //! Rust Standard Library](../std/index.html). It is the portable glue
 //! between the language and its libraries, defining the intrinsic and
 //! primitive building blocks of all Rust code. It links to no
 //! upstream libraries, no system libraries, and no libc.
 //!
 //! [^free]: Strictly speaking, there are some symbols which are needed but
 //!          they aren't always necessary.
 //!
 //! The core library is *minimal*: it isn't even aware of heap allocation,
 //! nor does it provide concurrency or I/O. These things require
 //! platform integration, and this library is platform-agnostic.
 //!
 //! # How to use the core library
 //!
 //! Please note that all of these details are currently not considered stable.
 //!
 // FIXME: Fill me in with more detail when the interface settles
 //! This library is built on the assumption of a few existing symbols:
 //!
 //! * `memcpy`, `memmove`, `memset`, `memcmp`, `bcmp`, `strlen` - These are core memory routines
 //!   which are generated by Rust codegen backends. Additionally, this library can make explicit
 //!   calls to `strlen`. Their signatures are the same as found in C, but there are extra
 //!   assumptions about their semantics: For `memcpy`, `memmove`, `memset`, `memcmp`, and `bcmp`, if
 //!   the `n` parameter is 0, the function is assumed to not be UB, even if the pointers are NULL or
 //!   dangling. (Note that making extra assumptions about these functions is common among compilers:
 //!   [clang](https://reviews.llvm.org/D86993) and [GCC](https://gcc.gnu.org/onlinedocs/gcc/Standards.html#C-Language) do the same.)
 //!   These functions are often provided by the system libc, but can also be provided by the
 //!   [compiler-builtins crate](https://crates.io/crates/compiler_builtins).
 //!   Note that the library does not guarantee that it will always make these assumptions, so Rust
 //!   user code directly calling the C functions should follow the C specification! The advice for
 //!   Rust user code is to call the functions provided by this library instead (such as
 //!   `ptr::copy`).
 //!
 //! * Panic handler - This function takes one argument, a `&panic::PanicInfo`. It is up to consumers of this core
 //!   library to define this panic function; it is only required to never
 //!   return. You should mark your implementation using `#[panic_handler]`.
 //!
 //! * `rust_eh_personality` - is used by the failure mechanisms of the
 //!    compiler. This is often mapped to GCC's personality function, but crates
 //!    which do not trigger a panic can be assured that this function is never
 //!    called. The `lang` attribute is called `eh_personality`.

 // Since core defines many fundamental lang items, all tests live in a
 // separate crate, libcoretest (library/core/tests), to avoid bizarre issues.
 //
 // Here we explicitly #[cfg]-out this whole crate when testing. If we don't do
 // this, both the generated test artifact and the linked libtest (which
 // transitively includes core) will both define the same set of lang items,
 // and this will cause the E0152 "found duplicate lang item" error. See
 // discussion in #50466 for details.
 //
 // This cfg won't affect doc tests.
 #![cfg(not(test))]
 //
 #![stable(feature = "core", since = "1.6.0")]
 #![doc(
     html_playground_url = "https://play.rust-lang.org/",
     issue_tracker_base_url = "https://github.com/rust-lang/rust/issues/",
     test(no_crate_inject, attr(deny(warnings))),
     test(attr(allow(dead_code, deprecated, unused_variables, unused_mut)))
 )]
 #![doc(rust_logo)]
 #![doc(cfg_hide(
     not(test),
     no_fp_fmt_parse,
     target_pointer_width = "16",
     target_pointer_width = "32",
     target_pointer_width = "64",
     target_has_atomic = "8",
     target_has_atomic = "16",
     target_has_atomic = "32",
     target_has_atomic = "64",
     target_has_atomic = "ptr",
     target_has_atomic_equal_alignment = "8",
     target_has_atomic_equal_alignment = "16",
     target_has_atomic_equal_alignment = "32",
     target_has_atomic_equal_alignment = "64",
     target_has_atomic_equal_alignment = "ptr",
     target_has_atomic_load_store = "8",
     target_has_atomic_load_store = "16",
     target_has_atomic_load_store = "32",
     target_has_atomic_load_store = "64",
     target_has_atomic_load_store = "ptr",
 ))]
 #![no_core]
 #![rustc_coherence_is_core]
 #![rustc_preserve_ub_checks]
 //
 // Lints:
 #![deny(rust_2021_incompatible_or_patterns)]
 #![deny(unsafe_op_in_unsafe_fn)]
 #![deny(fuzzy_provenance_casts)]
 #![warn(deprecated_in_future)]
 #![warn(missing_debug_implementations)]
 #![warn(missing_docs)]
 #![allow(explicit_outlives_requirements)]
 #![allow(incomplete_features)]
 #![warn(multiple_supertrait_upcastable)]
 #![allow(internal_features)]
 #![deny(ffi_unwind_calls)]
 // Do not check link redundancy on bootstraping phase
 #![allow(rustdoc::redundant_explicit_links)]
 //
 // Library features:
 // tidy-alphabetical-start
 #![feature(array_ptr_get)]
 #![feature(asm_experimental_arch)]
 #![feature(char_indices_offset)]
 #![feature(const_align_of_val)]
 #![feature(const_align_of_val_raw)]
 #![feature(const_align_offset)]
 #![feature(const_alloc_layout)]
 #![feature(const_arguments_as_str)]
 #![feature(const_array_from_ref)]
 #![feature(const_array_into_iter_constructors)]
 #![feature(const_bigint_helper_methods)]
 #![feature(const_black_box)]
 #![feature(const_cell_into_inner)]
 #![feature(const_eval_select)]
 #![feature(const_exact_div)]
 #![feature(const_float_bits_conv)]
 #![feature(const_float_classify)]
 #![feature(const_fmt_arguments_new)]
 #![feature(const_hash)]
 #![feature(const_heap)]
 #![feature(const_index_range_slice_index)]
 #![feature(const_intrinsic_copy)]
 #![feature(const_intrinsic_forget)]
 #![feature(const_ipv4)]
 #![feature(const_ipv6)]
 #![feature(const_likely)]
 #![feature(const_maybe_uninit_as_mut_ptr)]
 #![feature(const_maybe_uninit_assume_init)]
 #![feature(const_nonnull_new)]
 #![feature(const_num_midpoint)]
 #![feature(const_option)]
 #![feature(const_option_ext)]
 #![feature(const_pin)]
 #![feature(const_pointer_is_aligned)]
 #![feature(const_ptr_as_ref)]
 #![feature(const_ptr_is_null)]
 #![feature(const_ptr_sub_ptr)]
 #![feature(const_ptr_write)]
 #![feature(const_raw_ptr_comparison)]
 #![feature(const_replace)]
 #![feature(const_size_of_val)]
 #![feature(const_size_of_val_raw)]
 #![feature(const_slice_from_raw_parts_mut)]
 #![feature(const_slice_from_ref)]
 #![feature(const_slice_index)]
 #![feature(const_slice_split_at_mut)]
 #![feature(const_str_from_utf8_unchecked_mut)]
 #![feature(const_strict_overflow_ops)]
 #![feature(const_swap)]
 #![feature(const_try)]
 #![feature(const_type_id)]
 #![feature(const_type_name)]
 #![feature(const_typed_swap)]
 #![feature(const_ub_checks)]
 #![feature(const_unicode_case_lookup)]
 #![feature(const_unsafecell_get_mut)]
 #![feature(const_waker)]
 #![feature(coverage_attribute)]
 #![feature(do_not_recommend)]
 #![feature(duration_consts_float)]
 #![feature(internal_impls_macro)]
 #![feature(ip)]
 #![feature(is_ascii_octdigit)]
 #![feature(isqrt)]
 #![feature(link_cfg)]
 #![feature(offset_of_enum)]
 #![feature(offset_of_nested)]
 #![feature(panic_internals)]
 #![feature(ptr_alignment_type)]
 #![feature(ptr_metadata)]
 #![feature(set_ptr_value)]
 #![feature(slice_ptr_get)]
 #![feature(str_internals)]
 #![feature(str_split_inclusive_remainder)]
 #![feature(str_split_remainder)]
 #![feature(strict_provenance)]
 #![feature(ub_checks)]
 #![feature(unchecked_neg)]
 #![feature(unchecked_shifts)]
 #![feature(utf16_extra)]
 #![feature(utf16_extra_const)]
 #![feature(variant_count)]
 // tidy-alphabetical-end
 //
 // Language features:
 // tidy-alphabetical-start
 #![feature(abi_unadjusted)]
 #![feature(adt_const_params)]
 #![feature(allow_internal_unsafe)]
 #![feature(allow_internal_unstable)]
 #![feature(asm_const)]
 #![feature(auto_traits)]
 #![feature(cfg_sanitize)]
 #![feature(cfg_target_has_atomic)]
 #![feature(cfg_target_has_atomic_equal_alignment)]
 #![feature(const_fn_floating_point_arithmetic)]
 #![feature(const_for)]
 #![feature(const_mut_refs)]
 #![feature(const_precise_live_drops)]
 #![feature(const_refs_to_cell)]
 #![feature(decl_macro)]
 #![feature(deprecated_suggestion)]
 #![feature(doc_cfg)]
 #![feature(doc_cfg_hide)]
 #![feature(doc_notable_trait)]
 #![feature(extern_types)]
 #![feature(f128)]
 #![feature(f16)]
 #![feature(freeze_impls)]
 #![feature(fundamental)]
 #![feature(generic_arg_infer)]
 #![feature(if_let_guard)]
 #![feature(intra_doc_pointers)]
 #![feature(intrinsics)]
 #![feature(lang_items)]
 #![feature(let_chains)]
 #![feature(link_llvm_intrinsics)]
 #![feature(macro_metavar_expr)]
 #![feature(marker_trait_attr)]
 #![feature(min_exhaustive_patterns)]
 #![feature(min_specialization)]
 #![feature(multiple_supertrait_upcastable)]
 #![feature(must_not_suspend)]
 #![feature(negative_impls)]
 #![feature(never_type)]
 #![feature(no_core)]
 #![feature(no_sanitize)]
 #![feature(prelude_import)]
 #![feature(repr_simd)]
 #![feature(rustc_allow_const_fn_unstable)]
 #![feature(rustc_attrs)]
 #![feature(rustdoc_internals)]
 #![feature(simd_ffi)]
 #![feature(staged_api)]
 #![feature(stmt_expr_attributes)]
 #![feature(target_feature_11)]
 #![feature(trait_alias)]
 #![feature(transparent_unions)]
 #![feature(try_blocks)]
 #![feature(unboxed_closures)]
 #![feature(unsized_fn_params)]
 #![feature(with_negative_coherence)]
 // tidy-alphabetical-end
 //
 // Target features:
 // tidy-alphabetical-start
 #![feature(arm_target_feature)]
 #![feature(avx512_target_feature)]
 #![feature(hexagon_target_feature)]
 #![feature(loongarch_target_feature)]
 #![feature(mips_target_feature)]
 #![feature(powerpc_target_feature)]
 #![feature(riscv_target_feature)]
 #![feature(rtm_target_feature)]
 #![feature(sse4a_target_feature)]
 #![feature(tbm_target_feature)]
 #![feature(wasm_target_feature)]
 // tidy-alphabetical-end

 // allow using `core::` in intra-doc links
 #[allow(unused_extern_crates)]
 extern crate self as core;

 #[prelude_import]
 #[allow(unused)]
 use prelude::rust_2021::*;

 #[cfg(not(test))] // See #65860
 #[macro_use]
 mod macros;

 // We don't export this through #[macro_export] for now, to avoid breakage.
 // See https://github.com/rust-lang/rust/issues/82913
 #[cfg(not(test))]
 #[unstable(feature = "assert_matches", issue = "82775")]
 /// Unstable module containing the unstable `assert_matches` macro.
 pub mod assert_matches {
     #[unstable(feature = "assert_matches", issue = "82775")]
     pub use crate::macros::{assert_matches, debug_assert_matches};
 }

 #[unstable(feature = "cfg_match", issue = "115585")]
 pub use crate::macros::cfg_match;

 #[macro_use]
 mod internal_macros;

 #[path = "num/shells/int_macros.rs"]
 #[macro_use]
 mod int_macros;

 #[rustc_diagnostic_item = "i128_legacy_mod"]
 #[path = "num/shells/i128.rs"]
 pub mod i128;
 #[rustc_diagnostic_item = "i16_legacy_mod"]
 #[path = "num/shells/i16.rs"]
 pub mod i16;
 #[rustc_diagnostic_item = "i32_legacy_mod"]
 #[path = "num/shells/i32.rs"]
 pub mod i32;
 #[rustc_diagnostic_item = "i64_legacy_mod"]
 #[path = "num/shells/i64.rs"]
 pub mod i64;
 #[rustc_diagnostic_item = "i8_legacy_mod"]
 #[path = "num/shells/i8.rs"]
 pub mod i8;
 #[rustc_diagnostic_item = "isize_legacy_mod"]
 #[path = "num/shells/isize.rs"]
 pub mod isize;

 #[rustc_diagnostic_item = "u128_legacy_mod"]
 #[path = "num/shells/u128.rs"]
 pub mod u128;
 #[rustc_diagnostic_item = "u16_legacy_mod"]
 #[path = "num/shells/u16.rs"]
 pub mod u16;
 #[rustc_diagnostic_item = "u32_legacy_mod"]
 #[path = "num/shells/u32.rs"]
 pub mod u32;
 #[rustc_diagnostic_item = "u64_legacy_mod"]
 #[path = "num/shells/u64.rs"]
 pub mod u64;
 #[rustc_diagnostic_item = "u8_legacy_mod"]
 #[path = "num/shells/u8.rs"]
 pub mod u8;
 #[rustc_diagnostic_item = "usize_legacy_mod"]
 #[path = "num/shells/usize.rs"]
 pub mod usize;

 #[path = "num/f128.rs"]
 pub mod f128;
 #[path = "num/f16.rs"]
 pub mod f16;
 #[path = "num/f32.rs"]
 pub mod f32;
 #[path = "num/f64.rs"]
 pub mod f64;

 #[macro_use]
 pub mod num;

 /* The core prelude, not as all-encompassing as the std prelude */

 pub mod prelude;

 /* Core modules for ownership management */

 pub mod hint;
 pub mod intrinsics;
 pub mod mem;
 pub mod ptr;
 #[unstable(feature = "ub_checks", issue = "none")]
 pub mod ub_checks;

 /* Core language traits */

 pub mod borrow;
 pub mod clone;
 pub mod cmp;
 pub mod convert;
 pub mod default;
 pub mod error;
 pub mod marker;
 pub mod ops;

 /* Core types and methods on primitives */

 pub mod any;
 pub mod array;
 pub mod ascii;
 pub mod asserting;
 #[unstable(feature = "async_iterator", issue = "79024")]
 pub mod async_iter;
 pub mod cell;
 pub mod char;
 pub mod ffi;
 #[unstable(feature = "core_io_borrowed_buf", issue = "117693")]
 pub mod io;
 pub mod iter;
 pub mod net;
 pub mod option;
 pub mod panic;
 pub mod panicking;
 #[unstable(feature = "core_pattern_types", issue = "none")]
 pub mod pat;
 pub mod pin;
 #[unstable(feature = "new_range_api", issue = "125687")]
 pub mod range;
 pub mod result;
 pub mod sync;

 pub mod fmt;
 pub mod hash;
 pub mod slice;
 pub mod str;
 pub mod time;

 pub mod unicode;

 /* Async */
 pub mod future;
 pub mod task;

 /* Heap memory allocator trait */
 #[allow(missing_docs)]
 pub mod alloc;

 // note: does not need to be public
 mod bool;
 mod escape;
 mod tuple;
 mod unit;

 #[stable(feature = "core_primitive", since = "1.43.0")]
 pub mod primitive;

 // Pull in the `core_arch` crate directly into core. The contents of
 // `core_arch` are in a different repository: rust-lang/stdarch.
 //
 // `core_arch` depends on core, but the contents of this module are
 // set up in such a way that directly pulling it here works such that the
 // crate uses the this crate as its core.
 #[path = "../../stdarch/crates/core_arch/src/mod.rs"]
 #[allow(
     missing_docs,
     missing_debug_implementations,
     dead_code,
     unused_imports,
     unsafe_op_in_unsafe_fn,
     ambiguous_glob_reexports,
     deprecated_in_future
 )]
 #[allow(rustdoc::bare_urls)]
 mod core_arch;

 #[stable(feature = "simd_arch", since = "1.27.0")]
 pub mod arch;

 // Pull in the `core_simd` crate directly into core. The contents of
 // `core_simd` are in a different repository: rust-lang/portable-simd.
 //
 // `core_simd` depends on core, but the contents of this module are
 // set up in such a way that directly pulling it here works such that the
 // crate uses this crate as its core.
 #[path = "../../portable-simd/crates/core_simd/src/mod.rs"]
 #[allow(missing_debug_implementations, dead_code, unsafe_op_in_unsafe_fn)]
 #[allow(rustdoc::bare_urls)]
 #[unstable(feature = "portable_simd", issue = "86656")]
 mod core_simd;

 #[unstable(feature = "portable_simd", issue = "86656")]
 pub mod simd {
     #![doc = include_str!("../../portable-simd/crates/core_simd/src/core_simd_docs.md")]

     #[unstable(feature = "portable_simd", issue = "86656")]
     pub use crate::core_simd::simd::*;
 }

 include!("primitive_docs.rs");
	//! # The Rust Core Library
	//!
	//! The Rust Core Library is the dependency-free[^free] foundation of [The
	//! Rust Standard Library](../std/index.html). It is the portable glue
	//! between the language and its libraries, defining the intrinsic and
	//! primitive building blocks of all Rust code. It links to no
	//! upstream libraries, no system libraries, and no libc.
	//!
	//! [^free]: Strictly speaking, there are some symbols which are needed but
	//! they aren't always necessary.
	//!
	//! The core library is minimal: it isn't even aware of heap allocation,
	//! nor does it provide concurrency or I/O. These things require
	//! platform integration, and this library is platform-agnostic.
	//!
	//! # How to use the core library
	//!
	//! Please note that all of these details are currently not considered stable.
	//!
	// FIXME: Fill me in with more detail when the interface settles
	//! This library is built on the assumption of a few existing symbols:
	//!
	//! * `memcpy`, `memmove`, `memset`, `memcmp`, `bcmp`, `strlen` - These are core memory routines
	//! which are generated by Rust codegen backends. Additionally, this library can make explicit
	//! calls to `strlen`. Their signatures are the same as found in C, but there are extra
	//! assumptions about their semantics: For `memcpy`, `memmove`, `memset`, `memcmp`, and `bcmp`, if
	//! the `n` parameter is 0, the function is assumed to not be UB, even if the pointers are NULL or
	//! dangling. (Note that making extra assumptions about these functions is common among compilers:
	//! [clang](https://reviews.llvm.org/D86993) and [GCC](https://gcc.gnu.org/onlinedocs/gcc/Standards.html#C-Language) do the same.)
	//! These functions are often provided by the system libc, but can also be provided by the
	//! [compiler-builtins crate](https://crates.io/crates/compiler_builtins).
	//! Note that the library does not guarantee that it will always make these assumptions, so Rust
	//! user code directly calling the C functions should follow the C specification! The advice for
	//! Rust user code is to call the functions provided by this library instead (such as
	//! `ptr::copy`).
	//!
	//! * Panic handler - This function takes one argument, a `&panic::PanicInfo`. It is up to consumers of this core
	//! library to define this panic function; it is only required to never
	//! return. You should mark your implementation using `#[panic_handler]`.
	//!
	//! * `rust_eh_personality` - is used by the failure mechanisms of the
	//! compiler. This is often mapped to GCC's personality function, but crates
	//! which do not trigger a panic can be assured that this function is never
	//! called. The `lang` attribute is called `eh_personality`.

	// Since core defines many fundamental lang items, all tests live in a
	// separate crate, libcoretest (library/core/tests), to avoid bizarre issues.
	//
	// Here we explicitly #[cfg]-out this whole crate when testing. If we don't do
	// this, both the generated test artifact and the linked libtest (which
	// transitively includes core) will both define the same set of lang items,
	// and this will cause the E0152 "found duplicate lang item" error. See
	// discussion in #50466 for details.
	//
	// This cfg won't affect doc tests.
	#![cfg(not(test))]
	//
	#![stable(feature = "core", since = "1.6.0")]
	#![doc(
	html_playground_url = "https://play.rust-lang.org/",
	issue_tracker_base_url = "https://github.com/rust-lang/rust/issues/",
	test(no_crate_inject, attr(deny(warnings))),
	test(attr(allow(dead_code, deprecated, unused_variables, unused_mut)))
	)]
	#![doc(rust_logo)]
	#![doc(cfg_hide(
	not(test),
	no_fp_fmt_parse,
	target_pointer_width = "16",
	target_pointer_width = "32",
	target_pointer_width = "64",
	target_has_atomic = "8",
	target_has_atomic = "16",
	target_has_atomic = "32",
	target_has_atomic = "64",
	target_has_atomic = "ptr",
	target_has_atomic_equal_alignment = "8",
	target_has_atomic_equal_alignment = "16",
	target_has_atomic_equal_alignment = "32",
	target_has_atomic_equal_alignment = "64",
	target_has_atomic_equal_alignment = "ptr",
	target_has_atomic_load_store = "8",
	target_has_atomic_load_store = "16",
	target_has_atomic_load_store = "32",
	target_has_atomic_load_store = "64",
	target_has_atomic_load_store = "ptr",
	))]
	#![no_core]
	#![rustc_coherence_is_core]
	#![rustc_preserve_ub_checks]
	//
	// Lints:
	#![deny(rust_2021_incompatible_or_patterns)]
	#![deny(unsafe_op_in_unsafe_fn)]
	#![deny(fuzzy_provenance_casts)]
	#![warn(deprecated_in_future)]
	#![warn(missing_debug_implementations)]
	#![warn(missing_docs)]
	#![allow(explicit_outlives_requirements)]
	#![allow(incomplete_features)]
	#![warn(multiple_supertrait_upcastable)]
	#![allow(internal_features)]
	#![deny(ffi_unwind_calls)]
	// Do not check link redundancy on bootstraping phase
	#![allow(rustdoc::redundant_explicit_links)]
	//
	// Library features:
	// tidy-alphabetical-start
	#![feature(array_ptr_get)]
	#![feature(asm_experimental_arch)]
	#![feature(char_indices_offset)]
	#![feature(const_align_of_val)]
	#![feature(const_align_of_val_raw)]
	#![feature(const_align_offset)]
	#![feature(const_alloc_layout)]
	#![feature(const_arguments_as_str)]
	#![feature(const_array_from_ref)]
	#![feature(const_array_into_iter_constructors)]
	#![feature(const_bigint_helper_methods)]
	#![feature(const_black_box)]
	#![feature(const_cell_into_inner)]
	#![feature(const_eval_select)]
	#![feature(const_exact_div)]
	#![feature(const_float_bits_conv)]
	#![feature(const_float_classify)]
	#![feature(const_fmt_arguments_new)]
	#![feature(const_hash)]
	#![feature(const_heap)]
	#![feature(const_index_range_slice_index)]
	#![feature(const_intrinsic_copy)]
	#![feature(const_intrinsic_forget)]
	#![feature(const_ipv4)]
	#![feature(const_ipv6)]
	#![feature(const_likely)]
	#![feature(const_maybe_uninit_as_mut_ptr)]
	#![feature(const_maybe_uninit_assume_init)]
	#![feature(const_nonnull_new)]
	#![feature(const_num_midpoint)]
	#![feature(const_option)]
	#![feature(const_option_ext)]
	#![feature(const_pin)]
	#![feature(const_pointer_is_aligned)]
	#![feature(const_ptr_as_ref)]
	#![feature(const_ptr_is_null)]
	#![feature(const_ptr_sub_ptr)]
	#![feature(const_ptr_write)]
	#![feature(const_raw_ptr_comparison)]
	#![feature(const_replace)]
	#![feature(const_size_of_val)]
	#![feature(const_size_of_val_raw)]
	#![feature(const_slice_from_raw_parts_mut)]
	#![feature(const_slice_from_ref)]
	#![feature(const_slice_index)]
	#![feature(const_slice_split_at_mut)]
	#![feature(const_str_from_utf8_unchecked_mut)]
	#![feature(const_strict_overflow_ops)]
	#![feature(const_swap)]
	#![feature(const_try)]
	#![feature(const_type_id)]
	#![feature(const_type_name)]
	#![feature(const_typed_swap)]
	#![feature(const_ub_checks)]
	#![feature(const_unicode_case_lookup)]
	#![feature(const_unsafecell_get_mut)]
	#![feature(const_waker)]
	#![feature(coverage_attribute)]
	#![feature(do_not_recommend)]
	#![feature(duration_consts_float)]
	#![feature(internal_impls_macro)]
	#![feature(ip)]
	#![feature(is_ascii_octdigit)]
	#![feature(isqrt)]
	#![feature(link_cfg)]
	#![feature(offset_of_enum)]
	#![feature(offset_of_nested)]
	#![feature(panic_internals)]
	#![feature(ptr_alignment_type)]
	#![feature(ptr_metadata)]
	#![feature(set_ptr_value)]
	#![feature(slice_ptr_get)]
	#![feature(str_internals)]
	#![feature(str_split_inclusive_remainder)]
	#![feature(str_split_remainder)]
	#![feature(strict_provenance)]
	#![feature(ub_checks)]
	#![feature(unchecked_neg)]
	#![feature(unchecked_shifts)]
	#![feature(utf16_extra)]
	#![feature(utf16_extra_const)]
	#![feature(variant_count)]
	// tidy-alphabetical-end
	//
	// Language features:
	// tidy-alphabetical-start
	#![feature(abi_unadjusted)]
	#![feature(adt_const_params)]
	#![feature(allow_internal_unsafe)]
	#![feature(allow_internal_unstable)]
	#![feature(asm_const)]
	#![feature(auto_traits)]
	#![feature(cfg_sanitize)]
	#![feature(cfg_target_has_atomic)]
	#![feature(cfg_target_has_atomic_equal_alignment)]
	#![feature(const_fn_floating_point_arithmetic)]
	#![feature(const_for)]
	#![feature(const_mut_refs)]
	#![feature(const_precise_live_drops)]
	#![feature(const_refs_to_cell)]
	#![feature(decl_macro)]
	#![feature(deprecated_suggestion)]
	#![feature(doc_cfg)]
	#![feature(doc_cfg_hide)]
	#![feature(doc_notable_trait)]
	#![feature(extern_types)]
	#![feature(f128)]
	#![feature(f16)]
	#![feature(freeze_impls)]
	#![feature(fundamental)]
	#![feature(generic_arg_infer)]
	#![feature(if_let_guard)]
	#![feature(intra_doc_pointers)]
	#![feature(intrinsics)]
	#![feature(lang_items)]
	#![feature(let_chains)]
	#![feature(link_llvm_intrinsics)]
	#![feature(macro_metavar_expr)]
	#![feature(marker_trait_attr)]
	#![feature(min_exhaustive_patterns)]
	#![feature(min_specialization)]
	#![feature(multiple_supertrait_upcastable)]
	#![feature(must_not_suspend)]
	#![feature(negative_impls)]
	#![feature(never_type)]
	#![feature(no_core)]
	#![feature(no_sanitize)]
	#![feature(prelude_import)]
	#![feature(repr_simd)]
	#![feature(rustc_allow_const_fn_unstable)]
	#![feature(rustc_attrs)]
	#![feature(rustdoc_internals)]
	#![feature(simd_ffi)]
	#![feature(staged_api)]
	#![feature(stmt_expr_attributes)]
	#![feature(target_feature_11)]
	#![feature(trait_alias)]
	#![feature(transparent_unions)]
	#![feature(try_blocks)]
	#![feature(unboxed_closures)]
	#![feature(unsized_fn_params)]
	#![feature(with_negative_coherence)]
	// tidy-alphabetical-end
	//
	// Target features:
	// tidy-alphabetical-start
	#![feature(arm_target_feature)]
	#![feature(avx512_target_feature)]
	#![feature(hexagon_target_feature)]
	#![feature(loongarch_target_feature)]
	#![feature(mips_target_feature)]
	#![feature(powerpc_target_feature)]
	#![feature(riscv_target_feature)]
	#![feature(rtm_target_feature)]
	#![feature(sse4a_target_feature)]
	#![feature(tbm_target_feature)]
	#![feature(wasm_target_feature)]
	// tidy-alphabetical-end

	// allow using `core::` in intra-doc links
	#[allow(unused_extern_crates)]
	extern crate self as core;

	#[prelude_import]
	#[allow(unused)]
	use prelude::rust_2021::*;

	#[cfg(not(test))] // See #65860
	#[macro_use]
	mod macros;

	// We don't export this through #[macro_export] for now, to avoid breakage.
	// See https://github.com/rust-lang/rust/issues/82913
	#[cfg(not(test))]
	#[unstable(feature = "assert_matches", issue = "82775")]
	/// Unstable module containing the unstable `assert_matches` macro.
	pub mod assert_matches {
	#[unstable(feature = "assert_matches", issue = "82775")]
	pub use crate::macros::{assert_matches, debug_assert_matches};
	}

	#[unstable(feature = "cfg_match", issue = "115585")]
	pub use crate::macros::cfg_match;

	#[macro_use]
	mod internal_macros;

	#[path = "num/shells/int_macros.rs"]
	#[macro_use]
	mod int_macros;

	#[rustc_diagnostic_item = "i128_legacy_mod"]
	#[path = "num/shells/i128.rs"]
	pub mod i128;
	#[rustc_diagnostic_item = "i16_legacy_mod"]
	#[path = "num/shells/i16.rs"]
	pub mod i16;
	#[rustc_diagnostic_item = "i32_legacy_mod"]
	#[path = "num/shells/i32.rs"]
	pub mod i32;
	#[rustc_diagnostic_item = "i64_legacy_mod"]
	#[path = "num/shells/i64.rs"]
	pub mod i64;
	#[rustc_diagnostic_item = "i8_legacy_mod"]
	#[path = "num/shells/i8.rs"]
	pub mod i8;
	#[rustc_diagnostic_item = "isize_legacy_mod"]
	#[path = "num/shells/isize.rs"]
	pub mod isize;

	#[rustc_diagnostic_item = "u128_legacy_mod"]
	#[path = "num/shells/u128.rs"]
	pub mod u128;
	#[rustc_diagnostic_item = "u16_legacy_mod"]
	#[path = "num/shells/u16.rs"]
	pub mod u16;
	#[rustc_diagnostic_item = "u32_legacy_mod"]
	#[path = "num/shells/u32.rs"]
	pub mod u32;
	#[rustc_diagnostic_item = "u64_legacy_mod"]
	#[path = "num/shells/u64.rs"]
	pub mod u64;
	#[rustc_diagnostic_item = "u8_legacy_mod"]
	#[path = "num/shells/u8.rs"]
	pub mod u8;
	#[rustc_diagnostic_item = "usize_legacy_mod"]
	#[path = "num/shells/usize.rs"]
	pub mod usize;

	#[path = "num/f128.rs"]
	pub mod f128;
	#[path = "num/f16.rs"]
	pub mod f16;
	#[path = "num/f32.rs"]
	pub mod f32;
	#[path = "num/f64.rs"]
	pub mod f64;

	#[macro_use]
	pub mod num;

	/* The core prelude, not as all-encompassing as the std prelude */

	pub mod prelude;

	/* Core modules for ownership management */

	pub mod hint;
	pub mod intrinsics;
	pub mod mem;
	pub mod ptr;
	#[unstable(feature = "ub_checks", issue = "none")]
	pub mod ub_checks;

	/* Core language traits */

	pub mod borrow;
	pub mod clone;
	pub mod cmp;
	pub mod convert;
	pub mod default;
	pub mod error;
	pub mod marker;
	pub mod ops;

	/* Core types and methods on primitives */

	pub mod any;
	pub mod array;
	pub mod ascii;
	pub mod asserting;
	#[unstable(feature = "async_iterator", issue = "79024")]
	pub mod async_iter;
	pub mod cell;
	pub mod char;
	pub mod ffi;
	#[unstable(feature = "core_io_borrowed_buf", issue = "117693")]
	pub mod io;
	pub mod iter;
	pub mod net;
	pub mod option;
	pub mod panic;
	pub mod panicking;
	#[unstable(feature = "core_pattern_types", issue = "none")]
	pub mod pat;
	pub mod pin;
	#[unstable(feature = "new_range_api", issue = "125687")]
	pub mod range;
	pub mod result;
	pub mod sync;

	pub mod fmt;
	pub mod hash;
	pub mod slice;
	pub mod str;
	pub mod time;

	pub mod unicode;

	/* Async */
	pub mod future;
	pub mod task;

	/* Heap memory allocator trait */
	#[allow(missing_docs)]
	pub mod alloc;

	// note: does not need to be public
	mod bool;
	mod escape;
	mod tuple;
	mod unit;

	#[stable(feature = "core_primitive", since = "1.43.0")]
	pub mod primitive;

	// Pull in the `core_arch` crate directly into core. The contents of
	// `core_arch` are in a different repository: rust-lang/stdarch.
	//
	// `core_arch` depends on core, but the contents of this module are
	// set up in such a way that directly pulling it here works such that the
	// crate uses the this crate as its core.
	#[path = "../../stdarch/crates/core_arch/src/mod.rs"]
	#[allow(
	missing_docs,
	missing_debug_implementations,
	dead_code,
	unused_imports,
	unsafe_op_in_unsafe_fn,
	ambiguous_glob_reexports,
	deprecated_in_future
	)]
	#[allow(rustdoc::bare_urls)]
	mod core_arch;

	#[stable(feature = "simd_arch", since = "1.27.0")]
	pub mod arch;

	// Pull in the `core_simd` crate directly into core. The contents of
	// `core_simd` are in a different repository: rust-lang/portable-simd.
	//
	// `core_simd` depends on core, but the contents of this module are
	// set up in such a way that directly pulling it here works such that the
	// crate uses this crate as its core.
	#[path = "../../portable-simd/crates/core_simd/src/mod.rs"]
	#[allow(missing_debug_implementations, dead_code, unsafe_op_in_unsafe_fn)]
	#[allow(rustdoc::bare_urls)]
	#[unstable(feature = "portable_simd", issue = "86656")]
	mod core_simd;

	#[unstable(feature = "portable_simd", issue = "86656")]
	pub mod simd {
	#![doc = include_str!("../../portable-simd/crates/core_simd/src/core_simd_docs.md")]

	#[unstable(feature = "portable_simd", issue = "86656")]
	pub use crate::core_simd::simd::*;
	}

	include!("primitive_docs.rs");