67 lines
1.8 KiB
Rust
67 lines
1.8 KiB
Rust
|
use std::env;
|
||
|
|
use std::fs;
|
||
|
|
use std::path::Path;
|
||
|
|
use std::process::{Command, ExitStatus, Stdio};
|
||
|
|
use std::str;
|
||
|
|
|
||
|
|
// This code exercises the surface area that we expect of the Provider API. If
|
||
|
|
// the current toolchain is able to compile it, then thiserror is able to use
|
||
|
|
// providers for backtrace support.
|
||
|
|
const PROBE: &str = r#"
|
||
|
|
#![feature(provide_any)]
|
||
|
|
|
||
|
|
use std::any::{Demand, Provider};
|
||
|
|
|
||
|
|
fn _f<'a, P: Provider>(p: &'a P, demand: &mut Demand<'a>) {
|
||
|
|
p.provide(demand);
|
||
|
|
}
|
||
|
|
"#;
|
||
|
|
|
||
|
|
fn main() {
|
||
|
|
match compile_probe() {
|
||
|
|
Some(status) if status.success() => println!("cargo:rustc-cfg=provide_any"),
|
||
|
|
_ => {}
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
fn compile_probe() -> Option<ExitStatus> {
|
||
|
|
let rustc = env::var_os("RUSTC")?;
|
||
|
|
let out_dir = env::var_os("OUT_DIR")?;
|
||
|
|
let probefile = Path::new(&out_dir).join("probe.rs");
|
||
|
|
fs::write(&probefile, PROBE).ok()?;
|
||
|
|
|
||
|
|
// Make sure to pick up Cargo rustc configuration.
|
||
|
|
let mut cmd = if let Some(wrapper) = env::var_os("RUSTC_WRAPPER") {
|
||
|
|
let mut cmd = Command::new(wrapper);
|
||
|
|
// The wrapper's first argument is supposed to be the path to rustc.
|
||
|
|
cmd.arg(rustc);
|
||
|
|
cmd
|
||
|
|
} else {
|
||
|
|
Command::new(rustc)
|
||
|
|
};
|
||
|
|
|
||
|
|
cmd.stderr(Stdio::null())
|
||
|
|
.arg("--edition=2018")
|
||
|
|
.arg("--crate-name=thiserror_build")
|
||
|
|
.arg("--crate-type=lib")
|
||
|
|
.arg("--emit=metadata")
|
||
|
|
.arg("--out-dir")
|
||
|
|
.arg(out_dir)
|
||
|
|
.arg(probefile);
|
||
|
|
|
||
|
|
if let Some(target) = env::var_os("TARGET") {
|
||
|
|
cmd.arg("--target").arg(target);
|
||
|
|
}
|
||
|
|
|
||
|
|
// If Cargo wants to set RUSTFLAGS, use that.
|
||
|
|
if let Ok(rustflags) = env::var("CARGO_ENCODED_RUSTFLAGS") {
|
||
|
|
if !rustflags.is_empty() {
|
||
|
|
for arg in rustflags.split('\x1f') {
|
||
|
|
cmd.arg(arg);
|
||
|
|
}
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
cmd.status().ok()
|
||
|
|
}
|