49 lines
1.2 KiB
Rust
49 lines
1.2 KiB
Rust
use std::env;
|
|
use std::process::Command;
|
|
use std::str::{self, FromStr};
|
|
|
|
// The rustc-cfg strings below are *not* public API. Please let us know by
|
|
// opening a GitHub issue if your build environment requires some way to enable
|
|
// these cfgs other than by executing our build script.
|
|
fn main() {
|
|
let minor = match rustc_minor_version() {
|
|
Some(minor) => minor,
|
|
None => return,
|
|
};
|
|
|
|
// #[track_caller] stabilized in Rust 1.46:
|
|
// https://blog.rust-lang.org/2020/08/27/Rust-1.46.0.html#track_caller
|
|
if minor < 46 {
|
|
println!("cargo:rustc-cfg=no_track_caller");
|
|
}
|
|
}
|
|
|
|
fn rustc_minor_version() -> Option<u32> {
|
|
let rustc = match env::var_os("RUSTC") {
|
|
Some(rustc) => rustc,
|
|
None => return None,
|
|
};
|
|
|
|
let output = match Command::new(rustc).arg("--version").output() {
|
|
Ok(output) => output,
|
|
Err(_) => return None,
|
|
};
|
|
|
|
let version = match str::from_utf8(&output.stdout) {
|
|
Ok(version) => version,
|
|
Err(_) => return None,
|
|
};
|
|
|
|
let mut pieces = version.split('.');
|
|
if pieces.next() != Some("rustc 1") {
|
|
return None;
|
|
}
|
|
|
|
let next = match pieces.next() {
|
|
Some(next) => next,
|
|
None => return None,
|
|
};
|
|
|
|
u32::from_str(next).ok()
|
|
}
|