113: Use autocfg to probe for i128 r=cuviper a=cuviper



Co-authored-by: Josh Stone <cuviper@gmail.com>
This commit is contained in:
bors[bot] 2019-05-11 00:00:41 +00:00
commit 852ec9380f
2 changed files with 9 additions and 27 deletions

View File

@ -22,3 +22,6 @@ features = ["std"]
default = ["std"] default = ["std"]
std = [] std = []
i128 = [] i128 = []
[build-dependencies]
autocfg = "0.1.2"

View File

@ -1,35 +1,14 @@
extern crate autocfg;
use std::env; use std::env;
use std::io::Write;
use std::process::{Command, Stdio};
fn main() { fn main() {
if probe("fn main() { 0i128; }") { let ac = autocfg::new();
if ac.probe_type("i128") {
println!("cargo:rustc-cfg=has_i128"); println!("cargo:rustc-cfg=has_i128");
} else if env::var_os("CARGO_FEATURE_I128").is_some() { } else if env::var_os("CARGO_FEATURE_I128").is_some() {
panic!("i128 support was not detected!"); panic!("i128 support was not detected!");
} }
}
autocfg::rerun_path(file!());
/// Test if a code snippet can be compiled
fn probe(code: &str) -> bool {
let rustc = env::var_os("RUSTC").unwrap_or_else(|| "rustc".into());
let out_dir = env::var_os("OUT_DIR").expect("environment variable OUT_DIR");
let mut child = Command::new(rustc)
.arg("--out-dir")
.arg(out_dir)
.arg("--emit=obj")
.arg("-")
.stdin(Stdio::piped())
.spawn()
.expect("rustc probe");
child
.stdin
.as_mut()
.expect("rustc stdin")
.write_all(code.as_bytes())
.expect("write rustc stdin");
child.wait().expect("rustc probe").success()
} }