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 bootstrapping 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_select)]
104#![feature(cfg_target_has_reliable_f16_f128)]
105#![feature(const_carrying_mul_add)]
106#![feature(const_destruct)]
107#![feature(const_eval_select)]
108#![feature(core_intrinsics)]
109#![feature(coverage_attribute)]
110#![feature(disjoint_bitor)]
111#![feature(internal_impls_macro)]
112#![feature(ip)]
113#![feature(is_ascii_octdigit)]
114#![feature(lazy_get)]
115#![feature(link_cfg)]
116#![feature(offset_of_enum)]
117#![feature(panic_internals)]
118#![feature(ptr_alignment_type)]
119#![feature(ptr_metadata)]
120#![feature(set_ptr_value)]
121#![feature(slice_as_array)]
122#![feature(slice_ptr_get)]
123#![feature(str_internals)]
124#![feature(str_split_inclusive_remainder)]
125#![feature(str_split_remainder)]
126#![feature(ub_checks)]
127#![feature(unchecked_neg)]
128#![feature(unchecked_shifts)]
129#![feature(unsafe_pinned)]
130#![feature(utf16_extra)]
131#![feature(variant_count)]
132// tidy-alphabetical-end
133//
134// Language features:
135// tidy-alphabetical-start
136#![feature(abi_unadjusted)]
137#![feature(adt_const_params)]
138#![feature(allow_internal_unsafe)]
139#![feature(allow_internal_unstable)]
140#![feature(auto_traits)]
141#![feature(cfg_sanitize)]
142#![feature(cfg_target_has_atomic)]
143#![feature(cfg_target_has_atomic_equal_alignment)]
144#![feature(cfg_ub_checks)]
145#![feature(const_precise_live_drops)]
146#![feature(const_trait_impl)]
147#![feature(decl_macro)]
148#![feature(deprecated_suggestion)]
149#![feature(doc_cfg)]
150#![feature(doc_cfg_hide)]
151#![feature(doc_notable_trait)]
152#![feature(extern_types)]
153#![feature(f16)]
154#![feature(f128)]
155#![feature(freeze_impls)]
156#![feature(fundamental)]
157#![feature(if_let_guard)]
158#![feature(intra_doc_pointers)]
159#![feature(intrinsics)]
160#![feature(lang_items)]
161#![feature(link_llvm_intrinsics)]
162#![feature(macro_metavar_expr)]
163#![feature(marker_trait_attr)]
164#![feature(min_specialization)]
165#![feature(multiple_supertrait_upcastable)]
166#![feature(must_not_suspend)]
167#![feature(negative_impls)]
168#![feature(never_type)]
169#![feature(no_core)]
170#![feature(optimize_attribute)]
171#![feature(prelude_import)]
172#![feature(repr_simd)]
173#![feature(rustc_allow_const_fn_unstable)]
174#![feature(rustc_attrs)]
175#![feature(rustdoc_internals)]
176#![feature(simd_ffi)]
177#![feature(staged_api)]
178#![feature(stmt_expr_attributes)]
179#![feature(strict_provenance_lints)]
180#![feature(trait_alias)]
181#![feature(transparent_unions)]
182#![feature(try_blocks)]
183#![feature(unboxed_closures)]
184#![feature(unsized_fn_params)]
185#![feature(with_negative_coherence)]
186// tidy-alphabetical-end
187//
188// Target features:
189// tidy-alphabetical-start
190#![feature(aarch64_unstable_target_feature)]
191#![feature(arm_target_feature)]
192#![feature(hexagon_target_feature)]
193#![feature(loongarch_target_feature)]
194#![feature(mips_target_feature)]
195#![feature(powerpc_target_feature)]
196#![feature(riscv_target_feature)]
197#![feature(rtm_target_feature)]
198#![feature(s390x_target_feature)]
199#![feature(sse4a_target_feature)]
200#![feature(tbm_target_feature)]
201#![feature(wasm_target_feature)]
202#![feature(x86_amx_intrinsics)]
203// tidy-alphabetical-end
204
205// allow using `core::` in intra-doc links
206#[allow(unused_extern_crates)]
207extern crate self as core;
208
209#[prelude_import]
210#[allow(unused)]
211use prelude::rust_2024::*;
212
213#[macro_use]
214mod macros;
215
216#[unstable(feature = "assert_matches", issue = "82775")]
217/// Unstable module containing the unstable `assert_matches` macro.
218pub mod assert_matches {
219    #[unstable(feature = "assert_matches", issue = "82775")]
220    pub use crate::macros::{assert_matches, debug_assert_matches};
221}
222
223// We don't export this through #[macro_export] for now, to avoid breakage.
224#[unstable(feature = "autodiff", issue = "124509")]
225/// Unstable module containing the unstable `autodiff` macro.
226pub mod autodiff {
227    #[unstable(feature = "autodiff", issue = "124509")]
228    pub use crate::macros::builtin::{autodiff_forward, autodiff_reverse};
229}
230
231#[unstable(feature = "contracts", issue = "128044")]
232pub mod contracts;
233
234#[unstable(feature = "cfg_select", issue = "115585")]
235pub use crate::macros::cfg_select;
236
237#[macro_use]
238mod internal_macros;
239
240#[path = "num/shells/int_macros.rs"]
241#[macro_use]
242mod int_macros;
243
244#[rustc_diagnostic_item = "i128_legacy_mod"]
245#[path = "num/shells/i128.rs"]
246pub mod i128;
247#[rustc_diagnostic_item = "i16_legacy_mod"]
248#[path = "num/shells/i16.rs"]
249pub mod i16;
250#[rustc_diagnostic_item = "i32_legacy_mod"]
251#[path = "num/shells/i32.rs"]
252pub mod i32;
253#[rustc_diagnostic_item = "i64_legacy_mod"]
254#[path = "num/shells/i64.rs"]
255pub mod i64;
256#[rustc_diagnostic_item = "i8_legacy_mod"]
257#[path = "num/shells/i8.rs"]
258pub mod i8;
259#[rustc_diagnostic_item = "isize_legacy_mod"]
260#[path = "num/shells/isize.rs"]
261pub mod isize;
262
263#[rustc_diagnostic_item = "u128_legacy_mod"]
264#[path = "num/shells/u128.rs"]
265pub mod u128;
266#[rustc_diagnostic_item = "u16_legacy_mod"]
267#[path = "num/shells/u16.rs"]
268pub mod u16;
269#[rustc_diagnostic_item = "u32_legacy_mod"]
270#[path = "num/shells/u32.rs"]
271pub mod u32;
272#[rustc_diagnostic_item = "u64_legacy_mod"]
273#[path = "num/shells/u64.rs"]
274pub mod u64;
275#[rustc_diagnostic_item = "u8_legacy_mod"]
276#[path = "num/shells/u8.rs"]
277pub mod u8;
278#[rustc_diagnostic_item = "usize_legacy_mod"]
279#[path = "num/shells/usize.rs"]
280pub mod usize;
281
282#[path = "num/f128.rs"]
283pub mod f128;
284#[path = "num/f16.rs"]
285pub mod f16;
286#[path = "num/f32.rs"]
287pub mod f32;
288#[path = "num/f64.rs"]
289pub mod f64;
290
291#[macro_use]
292pub mod num;
293
294/* The core prelude, not as all-encompassing as the std prelude */
295
296pub mod prelude;
297
298/* Core modules for ownership management */
299
300pub mod hint;
301pub mod intrinsics;
302pub mod mem;
303pub mod ptr;
304#[unstable(feature = "ub_checks", issue = "none")]
305pub mod ub_checks;
306
307/* Core language traits */
308
309pub mod borrow;
310pub mod clone;
311pub mod cmp;
312pub mod convert;
313pub mod default;
314pub mod error;
315pub mod marker;
316pub mod ops;
317
318/* Core types and methods on primitives */
319
320pub mod any;
321pub mod array;
322pub mod ascii;
323pub mod asserting;
324#[unstable(feature = "async_iterator", issue = "79024")]
325pub mod async_iter;
326#[unstable(feature = "bstr", issue = "134915")]
327pub mod bstr;
328pub mod cell;
329pub mod char;
330pub mod ffi;
331#[unstable(feature = "core_io_borrowed_buf", issue = "117693")]
332pub mod io;
333pub mod iter;
334pub mod net;
335pub mod option;
336pub mod panic;
337pub mod panicking;
338#[unstable(feature = "pattern_type_macro", issue = "123646")]
339pub mod pat;
340pub mod pin;
341#[unstable(feature = "random", issue = "130703")]
342pub mod random;
343#[unstable(feature = "new_range_api", issue = "125687")]
344pub mod range;
345pub mod result;
346pub mod sync;
347#[unstable(feature = "unsafe_binders", issue = "130516")]
348pub mod unsafe_binder;
349
350pub mod fmt;
351pub mod hash;
352pub mod slice;
353pub mod str;
354pub mod time;
355
356pub mod unicode;
357
358/* Async */
359pub mod future;
360pub mod task;
361
362/* Heap memory allocator trait */
363#[allow(missing_docs)]
364pub mod alloc;
365
366// note: does not need to be public
367mod bool;
368mod escape;
369mod tuple;
370mod unit;
371
372#[stable(feature = "core_primitive", since = "1.43.0")]
373pub mod primitive;
374
375// Pull in the `core_arch` crate directly into core. The contents of
376// `core_arch` are in a different repository: rust-lang/stdarch.
377//
378// `core_arch` depends on core, but the contents of this module are
379// set up in such a way that directly pulling it here works such that the
380// crate uses the this crate as its core.
381#[path = "../../stdarch/crates/core_arch/src/mod.rs"]
382#[allow(
383    missing_docs,
384    missing_debug_implementations,
385    dead_code,
386    unused_imports,
387    unsafe_op_in_unsafe_fn,
388    ambiguous_glob_reexports,
389    deprecated_in_future,
390    unreachable_pub
391)]
392#[allow(rustdoc::bare_urls)]
393mod core_arch;
394
395#[stable(feature = "simd_arch", since = "1.27.0")]
396pub mod arch;
397
398// Pull in the `core_simd` crate directly into core. The contents of
399// `core_simd` are in a different repository: rust-lang/portable-simd.
400//
401// `core_simd` depends on core, but the contents of this module are
402// set up in such a way that directly pulling it here works such that the
403// crate uses this crate as its core.
404#[path = "../../portable-simd/crates/core_simd/src/mod.rs"]
405#[allow(missing_debug_implementations, dead_code, unsafe_op_in_unsafe_fn)]
406#[allow(rustdoc::bare_urls)]
407#[unstable(feature = "portable_simd", issue = "86656")]
408mod core_simd;
409
410#[unstable(feature = "portable_simd", issue = "86656")]
411pub mod simd {
412    #![doc = include_str!("../../portable-simd/crates/core_simd/src/core_simd_docs.md")]
413
414    #[unstable(feature = "portable_simd", issue = "86656")]
415    pub use crate::core_simd::simd::*;
416}
417
418include!("primitive_docs.rs");
core/lib.rs

core/
lib.rs
