Repository navigation
Expand file tree
/
Copy pathbuild.rs
More file actions
98 lines (84 loc) · 2.53 KB
/
Copy pathbuild.rs
File metadata and controls
98 lines (84 loc) · 2.53 KB
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
use std::env;
use std::fs;
use std::path::Path;
use std::process::{Command, ExitStatus};
use std::str;
// 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 eyre.
const BACKTRACE_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!()
}
}
"#;
const TRACK_CALLER_PROBE: &str = r#"
#![allow(dead_code)]
#[track_caller]
fn foo() {
let _location = std::panic::Location::caller();
}
"#;
fn main() {
match compile_probe(BACKTRACE_PROBE) {
Some(status) if status.success() => println!("cargo:rustc-cfg=backtrace"),
_ => {}
}
match compile_probe(TRACK_CALLER_PROBE) {
Some(status) if status.success() => println!("cargo:rustc-cfg=track_caller"),
_ => {}
}
let rustc = match rustc_minor_version() {
Some(rustc) => rustc,
None => return,
};
if rustc < 52 {
println!("cargo:rustc-cfg=eyre_no_fmt_arguments_as_str");
}
if rustc < 58 {
println!("cargo:rustc-cfg=eyre_no_fmt_args_capture");
}
}
fn compile_probe(probe: &str) -> 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()?;
Command::new(rustc)
.arg("--edition=2018")
.arg("--crate-name=eyre_build")
.arg("--crate-type=lib")
.arg("--emit=metadata")
.arg("--out-dir")
.arg(out_dir)
.arg(probefile)
.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()
}