|  | //! Run-time feature detection for the Rust standard library. | 
|  | //! | 
|  | //! To detect whether a feature is enabled in the system running the binary | 
|  | //! use one of the appropriate macro for the target: | 
|  | //! | 
|  | //! * `x86` and `x86_64`: [`is_x86_feature_detected`] | 
|  | //! * `arm`: [`is_arm_feature_detected`] | 
|  | //! * `aarch64`: [`is_aarch64_feature_detected`] | 
|  | //! * `mips`: [`is_mips_feature_detected`] | 
|  | //! * `mips64`: [`is_mips64_feature_detected`] | 
|  | //! * `powerpc`: [`is_powerpc_feature_detected`] | 
|  | //! * `powerpc64`: [`is_powerpc64_feature_detected`] | 
|  |  | 
|  | #![unstable(feature = "stdsimd", issue = "27731")] | 
|  | #![feature(const_fn, staged_api, stdsimd, doc_cfg, allow_internal_unstable)] | 
|  | #![allow(clippy::shadow_reuse)] | 
|  | #![deny(clippy::missing_inline_in_public_items)] | 
|  | #![cfg_attr(target_os = "linux", feature(linkage))] | 
|  | #![cfg_attr(all(target_os = "freebsd", target_arch = "aarch64"), feature(asm))] | 
|  | #![cfg_attr(stdsimd_strict, deny(warnings))] | 
|  | #![cfg_attr(test, allow(unused_imports))] | 
|  | #![no_std] | 
|  |  | 
|  | #[macro_use] | 
|  | extern crate cfg_if; | 
|  |  | 
|  | cfg_if! { | 
|  | if #[cfg(feature = "std_detect_file_io")] { | 
|  | #[cfg_attr(test, macro_use(println))] | 
|  | extern crate std; | 
|  |  | 
|  | #[allow(unused_imports)] | 
|  | use std::{arch, fs, io, mem, sync}; | 
|  | } else { | 
|  | #[cfg(test)] | 
|  | #[macro_use(println)] | 
|  | extern crate std; | 
|  |  | 
|  | #[allow(unused_imports)] | 
|  | use core::{arch, mem, sync}; | 
|  | } | 
|  | } | 
|  |  | 
|  | #[cfg(feature = "std_detect_dlsym_getauxval")] | 
|  | extern crate libc; | 
|  |  | 
|  | #[doc(hidden)] | 
|  | #[unstable(feature = "stdsimd", issue = "27731")] | 
|  | pub mod detect; |