src/tools/rustfmt/tests/source/cfg_if/lib.rs

//! 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;