bendns' repos / rust-analyzer
Unnamed repository; edit this file 'description' to name the repository.
Diffstat (limited to 'crates/project-model/src/toolchain_info/rustc_cfg.rs')
-rw-r--r--crates/project-model/src/toolchain_info/rustc_cfg.rs124
1 files changed, 124 insertions, 0 deletions
diff --git a/crates/project-model/src/toolchain_info/rustc_cfg.rs b/crates/project-model/src/toolchain_info/rustc_cfg.rs
new file mode 100644
index 0000000000..afcc812079
--- /dev/null
+++ b/crates/project-model/src/toolchain_info/rustc_cfg.rs
@@ -0,0 +1,124 @@
+//! Get the built-in cfg flags for the to be compile platform.
+
+use anyhow::Context;
+use cfg::CfgAtom;
+use rustc_hash::FxHashMap;
+use toolchain::Tool;
+
+use crate::{toolchain_info::QueryConfig, utf8_stdout};
+
+/// Uses `rustc --print cfg` to fetch the builtin cfgs.
+pub fn get(
+ config: QueryConfig<'_>,
+ target: Option<&str>,
+ extra_env: &FxHashMap<String, String>,
+) -> Vec<CfgAtom> {
+ let _p = tracing::info_span!("rustc_cfg::get").entered();
+
+ let rustc_cfgs = rustc_print_cfg(target, extra_env, config);
+ let rustc_cfgs = match rustc_cfgs {
+ Ok(cfgs) => cfgs,
+ Err(e) => {
+ tracing::error!(?e, "failed to get rustc cfgs");
+ return vec![];
+ }
+ };
+
+ // These are unstable but the standard libraries gate on them.
+ let unstable = vec![
+ r#"target_has_atomic_equal_alignment="8""#,
+ r#"target_has_atomic_equal_alignment="16""#,
+ r#"target_has_atomic_equal_alignment="32""#,
+ r#"target_has_atomic_equal_alignment="64""#,
+ r#"target_has_atomic_equal_alignment="128""#,
+ r#"target_has_atomic_equal_alignment="ptr""#,
+ r#"target_has_atomic_load_store"#,
+ r#"target_has_atomic_load_store="8""#,
+ r#"target_has_atomic_load_store="16""#,
+ r#"target_has_atomic_load_store="32""#,
+ r#"target_has_atomic_load_store="64""#,
+ r#"target_has_atomic_load_store="128""#,
+ r#"target_has_atomic_load_store="ptr""#,
+ r#"target_thread_local"#,
+ r#"target_has_atomic"#,
+ ];
+ let rustc_cfgs =
+ rustc_cfgs.lines().chain(unstable).map(crate::parse_cfg).collect::<Result<Vec<_>, _>>();
+ match rustc_cfgs {
+ Ok(rustc_cfgs) => {
+ tracing::debug!(?rustc_cfgs, "rustc cfgs found");
+ rustc_cfgs
+ }
+ Err(e) => {
+ tracing::error!(?e, "failed to parse rustc cfgs");
+ vec![]
+ }
+ }
+}
+
+fn rustc_print_cfg(
+ target: Option<&str>,
+ extra_env: &FxHashMap<String, String>,
+ config: QueryConfig<'_>,
+) -> anyhow::Result<String> {
+ const RUSTC_ARGS: [&str; 2] = ["--print", "cfg"];
+ let (sysroot, current_dir) = match config {
+ QueryConfig::Cargo(sysroot, cargo_toml) => {
+ let mut cmd = sysroot.tool(Tool::Cargo, cargo_toml.parent());
+ cmd.envs(extra_env);
+ cmd.args(["rustc"]).args(RUSTC_ARGS);
+ if let Some(target) = target {
+ cmd.args(["--target", target]);
+ }
+ cmd.args(["--", "-O"]);
+
+ match utf8_stdout(&mut cmd) {
+ Ok(it) => return Ok(it),
+ Err(e) => {
+ tracing::warn!(
+ %e,
+ "failed to run `{cmd:?}`, falling back to invoking rustc directly"
+ );
+ (sysroot, cargo_toml.parent().as_ref())
+ }
+ }
+ }
+ QueryConfig::Rustc(sysroot, current_dir) => (sysroot, current_dir),
+ };
+
+ let mut cmd = sysroot.tool(Tool::Rustc, current_dir);
+ cmd.envs(extra_env);
+ cmd.args(RUSTC_ARGS);
+ cmd.arg("-O");
+ if let Some(target) = target {
+ cmd.args(["--target", target]);
+ }
+
+ utf8_stdout(&mut cmd).with_context(|| format!("unable to fetch cfgs via `{cmd:?}`"))
+}
+
+#[cfg(test)]
+mod tests {
+ use paths::{AbsPathBuf, Utf8PathBuf};
+
+ use crate::{ManifestPath, Sysroot};
+
+ use super::*;
+
+ #[test]
+ fn cargo() {
+ let manifest_path = concat!(env!("CARGO_MANIFEST_DIR"), "/Cargo.toml");
+ let sysroot = Sysroot::empty();
+ let manifest_path =
+ ManifestPath::try_from(AbsPathBuf::assert(Utf8PathBuf::from(manifest_path))).unwrap();
+ let cfg = QueryConfig::Cargo(&sysroot, &manifest_path);
+ assert_ne!(get(cfg, None, &FxHashMap::default()), vec![]);
+ }
+
+ #[test]
+ fn rustc() {
+ let sysroot = Sysroot::empty();
+ let cfg = QueryConfig::Rustc(&sysroot, env!("CARGO_MANIFEST_DIR").as_ref());
+ assert_ne!(get(cfg, None, &FxHashMap::default()), vec![]);
+ }
+}