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.rs78
1 files changed, 78 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..82cb73bc35
--- /dev/null
+++ b/crates/project-model/src/toolchain_info/rustc_cfg.rs
@@ -0,0 +1,78 @@
+//! 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![];
+ }
+ };
+
+ let rustc_cfgs = rustc_cfgs.lines().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; 3] = ["--print", "cfg", "-O"];
+ let sysroot = match config {
+ QueryConfig::Cargo(sysroot, cargo_toml) => {
+ let mut cmd = sysroot.tool(Tool::Cargo);
+ cmd.envs(extra_env);
+ cmd.current_dir(cargo_toml.parent()).env("RUSTC_BOOTSTRAP", "1");
+ cmd.args(["rustc", "-Z", "unstable-options"]).args(RUSTC_ARGS);
+ if let Some(target) = target {
+ cmd.args(["--target", target]);
+ }
+
+ 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
+ }
+ }
+ }
+ QueryConfig::Rustc(sysroot) => sysroot,
+ };
+
+ let mut cmd = sysroot.tool(Tool::Rustc);
+ cmd.envs(extra_env);
+ cmd.args(RUSTC_ARGS);
+ if let Some(target) = target {
+ cmd.args(["--target", target]);
+ }
+
+ utf8_stdout(&mut cmd).with_context(|| format!("unable to fetch cfgs via `{cmd:?}`"))
+}