core/
lib.rs

1//! # The Rust Core Library
2//!
3//! The Rust Core Library is the dependency-free[^free] foundation of [The
4//! Rust Standard Library](../std/index.html). It is the portable glue
5//! between the language and its libraries, defining the intrinsic and
6//! primitive building blocks of all Rust code. It links to no
7//! upstream libraries, no system libraries, and no libc.
8//!
9//! [^free]: Strictly speaking, there are some symbols which are needed but
10//!          they aren't always necessary.
11//!
12//! The core library is *minimal*: it isn't even aware of heap allocation,
13//! nor does it provide concurrency or I/O. These things require
14//! platform integration, and this library is platform-agnostic.
15//!
16//! # How to use the core library
17//!
18//! Please note that all of these details are currently not considered stable.
19//!
20// FIXME: Fill me in with more detail when the interface settles
21//! This library is built on the assumption of a few existing symbols:
22//!
23//! * `memcpy`, `memmove`, `memset`, `memcmp`, `bcmp`, `strlen` - These are core memory routines
24//!   which are generated by Rust codegen backends. Additionally, this library can make explicit
25//!   calls to `strlen`. Their signatures are the same as found in C, but there are extra
26//!   assumptions about their semantics: For `memcpy`, `memmove`, `memset`, `memcmp`, and `bcmp`, if
27//!   the `n` parameter is 0, the function is assumed to not be UB, even if the pointers are NULL or
28//!   dangling. (Note that making extra assumptions about these functions is common among compilers:
29//!   [clang](https://reviews.llvm.org/D86993) and [GCC](https://gcc.gnu.org/onlinedocs/gcc/Standards.html#C-Language) do the same.)
30//!   These functions are often provided by the system libc, but can also be provided by the
31//!   [compiler-builtins crate](https://crates.io/crates/compiler_builtins).
32//!   Note that the library does not guarantee that it will always make these assumptions, so Rust
33//!   user code directly calling the C functions should follow the C specification! The advice for
34//!   Rust user code is to call the functions provided by this library instead (such as
35//!   `ptr::copy`).
36//!
37//! * Panic handler - This function takes one argument, a `&panic::PanicInfo`. It is up to consumers of this core
38//!   library to define this panic function; it is only required to never
39//!   return. You should mark your implementation using `#[panic_handler]`.
40//!
41//! * `rust_eh_personality` - is used by the failure mechanisms of the
42//!    compiler. This is often mapped to GCC's personality function, but crates
43//!    which do not trigger a panic can be assured that this function is never
44//!    called. The `lang` attribute is called `eh_personality`.
45
46#![stable(feature = "core", since = "1.6.0")]
47#![doc(
48    html_playground_url = "https://play.rust-lang.org/",
49    issue_tracker_base_url = "https://github.com/rust-lang/rust/issues/",
50    test(no_crate_inject, attr(deny(warnings))),
51    test(attr(allow(dead_code, deprecated, unused_variables, unused_mut)))
52)]
53#![doc(rust_logo)]
54#![doc(cfg_hide(
55    no_fp_fmt_parse,
56    target_pointer_width = "16",
57    target_pointer_width = "32",
58    target_pointer_width = "64",
59    target_has_atomic = "8",
60    target_has_atomic = "16",
61    target_has_atomic = "32",
62    target_has_atomic = "64",
63    target_has_atomic = "ptr",
64    target_has_atomic_equal_alignment = "8",
65    target_has_atomic_equal_alignment = "16",
66    target_has_atomic_equal_alignment = "32",
67    target_has_atomic_equal_alignment = "64",
68    target_has_atomic_equal_alignment = "ptr",
69    target_has_atomic_load_store = "8",
70    target_has_atomic_load_store = "16",
71    target_has_atomic_load_store = "32",
72    target_has_atomic_load_store = "64",
73    target_has_atomic_load_store = "ptr",
74))]
75#![no_core]
76#![rustc_coherence_is_core]
77#![rustc_preserve_ub_checks]
78//
79// Lints:
80#![deny(rust_2021_incompatible_or_patterns)]
81#![deny(unsafe_op_in_unsafe_fn)]
82#![deny(fuzzy_provenance_casts)]
83#![warn(deprecated_in_future)]
84#![warn(missing_debug_implementations)]
85#![warn(missing_docs)]
86#![allow(explicit_outlives_requirements)]
87#![allow(incomplete_features)]
88#![warn(multiple_supertrait_upcastable)]
89#![allow(internal_features)]
90#![deny(ffi_unwind_calls)]
91#![warn(unreachable_pub)]
92// Do not check link redundancy on bootstraping phase
93#![allow(rustdoc::redundant_explicit_links)]
94#![warn(rustdoc::unescaped_backticks)]
95//
96// Library features:
97// tidy-alphabetical-start
98#![feature(array_ptr_get)]
99#![feature(asm_experimental_arch)]
100#![feature(bigint_helper_methods)]
101#![feature(bstr)]
102#![feature(bstr_internals)]
103#![feature(cfg_match)]
104#![feature(const_carrying_mul_add)]
105#![feature(const_eval_select)]
106#![feature(core_intrinsics)]
107#![feature(coverage_attribute)]
108#![feature(disjoint_bitor)]
109#![feature(internal_impls_macro)]
110#![feature(ip)]
111#![feature(is_ascii_octdigit)]
112#![feature(lazy_get)]
113#![feature(link_cfg)]
114#![feature(non_null_from_ref)]
115#![feature(offset_of_enum)]
116#![feature(panic_internals)]
117#![feature(ptr_alignment_type)]
118#![feature(ptr_metadata)]
119#![feature(set_ptr_value)]
120#![feature(slice_as_array)]
121#![feature(slice_ptr_get)]
122#![feature(str_internals)]
123#![feature(str_split_inclusive_remainder)]
124#![feature(str_split_remainder)]
125#![feature(ub_checks)]
126#![feature(unchecked_neg)]
127#![feature(unchecked_shifts)]
128#![feature(unsafe_pinned)]
129#![feature(utf16_extra)]
130#![feature(variant_count)]
131// tidy-alphabetical-end
132//
133// Language features:
134// tidy-alphabetical-start
135#![feature(abi_unadjusted)]
136#![feature(adt_const_params)]
137#![feature(allow_internal_unsafe)]
138#![feature(allow_internal_unstable)]
139#![feature(auto_traits)]
140#![feature(cfg_sanitize)]
141#![feature(cfg_target_has_atomic)]
142#![feature(cfg_target_has_atomic_equal_alignment)]
143#![feature(cfg_ub_checks)]
144#![feature(const_precise_live_drops)]
145#![feature(const_trait_impl)]
146#![feature(decl_macro)]
147#![feature(deprecated_suggestion)]
148#![feature(doc_cfg)]
149#![feature(doc_cfg_hide)]
150#![feature(doc_notable_trait)]
151#![feature(extern_types)]
152#![feature(f128)]
153#![feature(f16)]
154#![feature(freeze_impls)]
155#![feature(fundamental)]
156#![feature(generic_arg_infer)]
157#![feature(if_let_guard)]
158#![feature(intra_doc_pointers)]
159#![feature(intrinsics)]
160#![feature(lang_items)]
161#![feature(let_chains)]
162#![feature(link_llvm_intrinsics)]
163#![feature(macro_metavar_expr)]
164#![feature(marker_trait_attr)]
165#![feature(min_specialization)]
166#![feature(multiple_supertrait_upcastable)]
167#![feature(must_not_suspend)]
168#![feature(negative_impls)]
169#![feature(never_type)]
170#![feature(no_core)]
171#![feature(optimize_attribute)]
172#![feature(prelude_import)]
173#![feature(repr_simd)]
174#![feature(rustc_allow_const_fn_unstable)]
175#![feature(rustc_attrs)]
176#![feature(rustdoc_internals)]
177#![feature(simd_ffi)]
178#![feature(staged_api)]
179#![feature(stmt_expr_attributes)]
180#![feature(strict_provenance_lints)]
181#![feature(trait_alias)]
182#![feature(transparent_unions)]
183#![feature(try_blocks)]
184#![feature(unboxed_closures)]
185#![feature(unsized_fn_params)]
186#![feature(with_negative_coherence)]
187// tidy-alphabetical-end
188//
189// Target features:
190// tidy-alphabetical-start
191#![feature(aarch64_unstable_target_feature)]
192#![feature(arm_target_feature)]
193#![feature(avx512_target_feature)]
194#![feature(hexagon_target_feature)]
195#![feature(keylocker_x86)]
196#![feature(loongarch_target_feature)]
197#![feature(mips_target_feature)]
198#![feature(powerpc_target_feature)]
199#![feature(riscv_target_feature)]
200#![feature(rtm_target_feature)]
201#![feature(s390x_target_feature)]
202#![feature(sha512_sm_x86)]
203#![feature(sse4a_target_feature)]
204#![feature(tbm_target_feature)]
205#![feature(wasm_target_feature)]
206#![feature(x86_amx_intrinsics)]
207// tidy-alphabetical-end
208
209// allow using `core::` in intra-doc links
210#[allow(unused_extern_crates)]
211extern crate self as core;
212
213#[prelude_import]
214#[allow(unused)]
215use prelude::rust_2024::*;
216
217#[macro_use]
218mod macros;
219
220#[unstable(feature = "assert_matches", issue = "82775")]
221/// Unstable module containing the unstable `assert_matches` macro.
222pub mod assert_matches {
223    #[unstable(feature = "assert_matches", issue = "82775")]
224    pub use crate::macros::{assert_matches, debug_assert_matches};
225}
226
227// We don't export this through #[macro_export] for now, to avoid breakage.
228#[unstable(feature = "autodiff", issue = "124509")]
229/// Unstable module containing the unstable `autodiff` macro.
230pub mod autodiff {
231    #[unstable(feature = "autodiff", issue = "124509")]
232    pub use crate::macros::builtin::autodiff;
233}
234
235#[unstable(feature = "contracts", issue = "128044")]
236pub mod contracts;
237
238#[unstable(feature = "cfg_match", issue = "115585")]
239pub use crate::macros::cfg_match;
240
241#[macro_use]
242mod internal_macros;
243
244#[path = "num/shells/int_macros.rs"]
245#[macro_use]
246mod int_macros;
247
248#[rustc_diagnostic_item = "i128_legacy_mod"]
249#[path = "num/shells/i128.rs"]
250pub mod i128;
251#[rustc_diagnostic_item = "i16_legacy_mod"]
252#[path = "num/shells/i16.rs"]
253pub mod i16;
254#[rustc_diagnostic_item = "i32_legacy_mod"]
255#[path = "num/shells/i32.rs"]
256pub mod i32;
257#[rustc_diagnostic_item = "i64_legacy_mod"]
258#[path = "num/shells/i64.rs"]
259pub mod i64;
260#[rustc_diagnostic_item = "i8_legacy_mod"]
261#[path = "num/shells/i8.rs"]
262pub mod i8;
263#[rustc_diagnostic_item = "isize_legacy_mod"]
264#[path = "num/shells/isize.rs"]
265pub mod isize;
266
267#[rustc_diagnostic_item = "u128_legacy_mod"]
268#[path = "num/shells/u128.rs"]
269pub mod u128;
270#[rustc_diagnostic_item = "u16_legacy_mod"]
271#[path = "num/shells/u16.rs"]
272pub mod u16;
273#[rustc_diagnostic_item = "u32_legacy_mod"]
274#[path = "num/shells/u32.rs"]
275pub mod u32;
276#[rustc_diagnostic_item = "u64_legacy_mod"]
277#[path = "num/shells/u64.rs"]
278pub mod u64;
279#[rustc_diagnostic_item = "u8_legacy_mod"]
280#[path = "num/shells/u8.rs"]
281pub mod u8;
282#[rustc_diagnostic_item = "usize_legacy_mod"]
283#[path = "num/shells/usize.rs"]
284pub mod usize;
285
286#[path = "num/f128.rs"]
287pub mod f128;
288#[path = "num/f16.rs"]
289pub mod f16;
290#[path = "num/f32.rs"]
291pub mod f32;
292#[path = "num/f64.rs"]
293pub mod f64;
294
295#[macro_use]
296pub mod num;
297
298/* The core prelude, not as all-encompassing as the std prelude */
299
300pub mod prelude;
301
302/* Core modules for ownership management */
303
304pub mod hint;
305pub mod intrinsics;
306pub mod mem;
307pub mod ptr;
308#[unstable(feature = "ub_checks", issue = "none")]
309pub mod ub_checks;
310
311/* Core language traits */
312
313pub mod borrow;
314pub mod clone;
315pub mod cmp;
316pub mod convert;
317pub mod default;
318pub mod error;
319pub mod marker;
320pub mod ops;
321
322/* Core types and methods on primitives */
323
324pub mod any;
325pub mod array;
326pub mod ascii;
327pub mod asserting;
328#[unstable(feature = "async_iterator", issue = "79024")]
329pub mod async_iter;
330#[unstable(feature = "bstr", issue = "134915")]
331pub mod bstr;
332pub mod cell;
333pub mod char;
334pub mod ffi;
335#[unstable(feature = "core_io_borrowed_buf", issue = "117693")]
336pub mod io;
337pub mod iter;
338pub mod net;
339pub mod option;
340pub mod panic;
341pub mod panicking;
342#[unstable(feature = "pattern_type_macro", issue = "123646")]
343pub mod pat;
344pub mod pin;
345#[unstable(feature = "random", issue = "130703")]
346pub mod random;
347#[unstable(feature = "new_range_api", issue = "125687")]
348pub mod range;
349pub mod result;
350pub mod sync;
351#[unstable(feature = "unsafe_binders", issue = "130516")]
352pub mod unsafe_binder;
353
354pub mod fmt;
355pub mod hash;
356pub mod slice;
357pub mod str;
358pub mod time;
359
360pub mod unicode;
361
362/* Async */
363pub mod future;
364pub mod task;
365
366/* Heap memory allocator trait */
367#[allow(missing_docs)]
368pub mod alloc;
369
370// note: does not need to be public
371mod bool;
372mod escape;
373mod tuple;
374mod unit;
375
376#[stable(feature = "core_primitive", since = "1.43.0")]
377pub mod primitive;
378
379// Pull in the `core_arch` crate directly into core. The contents of
380// `core_arch` are in a different repository: rust-lang/stdarch.
381//
382// `core_arch` depends on core, but the contents of this module are
383// set up in such a way that directly pulling it here works such that the
384// crate uses the this crate as its core.
385#[path = "../../stdarch/crates/core_arch/src/mod.rs"]
386#[allow(
387    missing_docs,
388    missing_debug_implementations,
389    dead_code,
390    unused_imports,
391    unsafe_op_in_unsafe_fn,
392    ambiguous_glob_reexports,
393    deprecated_in_future,
394    unreachable_pub
395)]
396#[allow(rustdoc::bare_urls)]
397mod core_arch;
398
399#[stable(feature = "simd_arch", since = "1.27.0")]
400pub mod arch;
401
402// Pull in the `core_simd` crate directly into core. The contents of
403// `core_simd` are in a different repository: rust-lang/portable-simd.
404//
405// `core_simd` depends on core, but the contents of this module are
406// set up in such a way that directly pulling it here works such that the
407// crate uses this crate as its core.
408#[path = "../../portable-simd/crates/core_simd/src/mod.rs"]
409#[allow(missing_debug_implementations, dead_code, unsafe_op_in_unsafe_fn)]
410#[allow(rustdoc::bare_urls)]
411#[unstable(feature = "portable_simd", issue = "86656")]
412mod core_simd;
413
414#[unstable(feature = "portable_simd", issue = "86656")]
415pub mod simd {
416    #![doc = include_str!("../../portable-simd/crates/core_simd/src/core_simd_docs.md")]
417
418    #[unstable(feature = "portable_simd", issue = "86656")]
419    pub use crate::core_simd::simd::*;
420}
421
422include!("primitive_docs.rs");
core/lib.rs

core/
lib.rs
