114 lines
3.0 KiB
Rust
114 lines
3.0 KiB
Rust
#![allow(clippy::option_if_let_else)]
|
|
|
|
use std::env;
|
|
use std::fs;
|
|
use std::path::Path;
|
|
use std::process::{Command, ExitStatus, Stdio};
|
|
use std::str;
|
|
|
|
#[cfg(all(feature = "backtrace", not(feature = "std")))]
|
|
compile_error! {
|
|
"`backtrace` feature without `std` feature is not supported"
|
|
}
|
|
|
|
// This code exercises the surface area that we expect of the std Backtrace
|
|
// type. If the current toolchain is able to compile it, we go ahead and use
|
|
// backtrace in anyhow.
|
|
const PROBE: &str = r#"
|
|
#![feature(backtrace)]
|
|
#![allow(dead_code)]
|
|
|
|
use std::backtrace::{Backtrace, BacktraceStatus};
|
|
use std::error::Error;
|
|
use std::fmt::{self, Display};
|
|
|
|
#[derive(Debug)]
|
|
struct E;
|
|
|
|
impl Display for E {
|
|
fn fmt(&self, _formatter: &mut fmt::Formatter) -> fmt::Result {
|
|
unimplemented!()
|
|
}
|
|
}
|
|
|
|
impl Error for E {
|
|
fn backtrace(&self) -> Option<&Backtrace> {
|
|
let backtrace = Backtrace::capture();
|
|
match backtrace.status() {
|
|
BacktraceStatus::Captured | BacktraceStatus::Disabled | _ => {}
|
|
}
|
|
unimplemented!()
|
|
}
|
|
}
|
|
"#;
|
|
|
|
fn main() {
|
|
if cfg!(feature = "std") {
|
|
match compile_probe() {
|
|
Some(status) if status.success() => println!("cargo:rustc-cfg=backtrace"),
|
|
_ => {}
|
|
}
|
|
}
|
|
|
|
let rustc = match rustc_minor_version() {
|
|
Some(rustc) => rustc,
|
|
None => return,
|
|
};
|
|
|
|
if rustc < 51 {
|
|
println!("cargo:rustc-cfg=anyhow_no_ptr_addr_of");
|
|
}
|
|
|
|
if rustc < 52 {
|
|
println!("cargo:rustc-cfg=anyhow_no_fmt_arguments_as_str");
|
|
}
|
|
}
|
|
|
|
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("CARGO_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=anyhow_build")
|
|
.arg("--crate-type=lib")
|
|
.arg("--emit=metadata")
|
|
.arg("--out-dir")
|
|
.arg(out_dir)
|
|
.arg(probefile);
|
|
|
|
// 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()
|
|
}
|
|
|
|
fn rustc_minor_version() -> Option<u32> {
|
|
let rustc = env::var_os("RUSTC")?;
|
|
let output = Command::new(rustc).arg("--version").output().ok()?;
|
|
let version = str::from_utf8(&output.stdout).ok()?;
|
|
let mut pieces = version.split('.');
|
|
if pieces.next() != Some("rustc 1") {
|
|
return None;
|
|
}
|
|
pieces.next()?.parse().ok()
|
|
}
|