libc-rs/build.rs

36 lines
916 B
Rust
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use std::env;
use std::process::Command;
use std::str;
fn main() {
/*
* If `core::ffi::c_void` exists, libc can just re-export it. Otherwise, it
* must define an incompatible type to retain backwards-compatibility.
*/
if rustc_minor_version().expect("Failed to get rustc version") >= 31 {
println!("cargo:rustc-cfg=core_cvoid");
}
}
fn rustc_minor_version() -> Option<u32> {
macro_rules! otry {
($e:expr) => {
match $e {
Some(e) => e,
None => return None,
}
};
}
let rustc = otry!(env::var_os("RUSTC"));
let output = otry!(Command::new(rustc).arg("--version").output().ok());
let version = otry!(str::from_utf8(&output.stdout).ok());
let mut pieces = version.split('.');
if pieces.next() != Some("rustc 1") {
return None;
}
otry!(pieces.next()).parse().ok()
}