project_model/toolchain_info/
target_data_layout.rs

1//! Runs `rustc --print target-spec-json` to get the target_data_layout.
2
3use anyhow::Context;
4use rustc_hash::FxHashMap;
5use toolchain::Tool;
6
7use crate::{Sysroot, toolchain_info::QueryConfig, utf8_stdout};
8
9/// Uses `rustc --print target-spec-json`.
10pub fn get(
11    config: QueryConfig<'_>,
12    target: Option<&str>,
13    extra_env: &FxHashMap<String, Option<String>>,
14) -> anyhow::Result<String> {
15    const RUSTC_ARGS: [&str; 2] = ["--print", "target-spec-json"];
16    let process = |output: String| {
17        (|| Some(output.split_once(r#""data-layout": ""#)?.1.split_once('"')?.0.to_owned()))()
18            .ok_or_else(|| {
19                anyhow::format_err!("could not parse target-spec-json from command output")
20            })
21    };
22    let (sysroot, current_dir) = match config {
23        QueryConfig::Cargo(sysroot, cargo_toml, _) => {
24            let mut cmd = sysroot.tool(Tool::Cargo, cargo_toml.parent(), extra_env);
25            cmd.env("RUSTC_BOOTSTRAP", "1");
26            cmd.args(["rustc", "-Z", "unstable-options"]).args(RUSTC_ARGS);
27            if let Some(target) = target {
28                cmd.args(["--target", target]);
29            }
30            cmd.args(["--", "-Z", "unstable-options"]);
31            match utf8_stdout(&mut cmd) {
32                Ok(output) => return process(output),
33                Err(e) => {
34                    tracing::warn!(%e, "failed to run `{cmd:?}`, falling back to invoking rustc directly");
35                    (sysroot, cargo_toml.parent().as_ref())
36                }
37            }
38        }
39        QueryConfig::Rustc(sysroot, current_dir) => (sysroot, current_dir),
40    };
41
42    let mut cmd = Sysroot::tool(sysroot, Tool::Rustc, current_dir, extra_env);
43    cmd.env("RUSTC_BOOTSTRAP", "1").args(["-Z", "unstable-options"]).args(RUSTC_ARGS);
44    if let Some(target) = target {
45        cmd.args(["--target", target]);
46    }
47    utf8_stdout(&mut cmd)
48        .with_context(|| format!("unable to fetch target-data-layout via `{cmd:?}`"))
49        .and_then(process)
50}
51
52#[cfg(test)]
53mod tests {
54    use paths::{AbsPathBuf, Utf8PathBuf};
55
56    use crate::{ManifestPath, Sysroot};
57
58    use super::*;
59
60    #[test]
61    fn cargo() {
62        let manifest_path = concat!(env!("CARGO_MANIFEST_DIR"), "/Cargo.toml");
63        let sysroot = Sysroot::empty();
64        let manifest_path =
65            ManifestPath::try_from(AbsPathBuf::assert(Utf8PathBuf::from(manifest_path))).unwrap();
66        let cfg = QueryConfig::Cargo(&sysroot, &manifest_path, &None);
67        assert!(get(cfg, None, &FxHashMap::default()).is_ok());
68    }
69
70    #[test]
71    fn rustc() {
72        let sysroot = Sysroot::empty();
73        let cfg = QueryConfig::Rustc(&sysroot, env!("CARGO_MANIFEST_DIR").as_ref());
74        assert!(get(cfg, None, &FxHashMap::default()).is_ok());
75    }
76}
project_model/toolchain_info/target_data_layout.rs

project_model/toolchain_info/
target_data_layout.rs
