From 2826eb51aa60e2e73d7f35408d2ee2727ec36334 Mon Sep 17 00:00:00 2001
From: Chase Douglas <chase@stackery.io>
Date: Tue, 20 Feb 2024 16:49:07 -0800
Subject: [PATCH] Don't build dependencies when retrieving target data layout
`cargo rustc -- <args>` first builds dependencies then calls `rustc <args>` for the current package. Here, we don't want to build dependencies, we just want to call `rustc --print`. An unstable `cargo rustc` `--print` command bypasses building dependencies first. This speeds up execution of this code path and ensures RA doesn't recompile dependencies with the `RUSTC_BOOTSRAP=1` env var flag set.
Note that we must pass `-Z unstable-options` twice, first to enable the `cargo` unstable `--print` flag, then later to enable the unstable `rustc` `target-spec-json` print request.
---
crates/project-model/src/target_data_layout.rs | 11 ++++++++++-
1 file changed, 10 insertions(+), 1 deletion(-)
diff --git a/crates/project-model/src/target_data_layout.rs b/crates/project-model/src/target_data_layout.rs
index af635dda578..98917351c5e 100644
--- a/crates/project-model/src/target_data_layout.rs
+++ b/crates/project-model/src/target_data_layout.rs
@@ -32,7 +32,16 @@ pub fn get(
Sysroot::set_rustup_toolchain_env(&mut cmd, sysroot);
cmd.envs(extra_env);
cmd.current_dir(cargo_toml.parent())
- .args(["rustc", "--", "-Z", "unstable-options", "--print", "target-spec-json"])
+ .args([
+ "rustc",
+ "-Z",
+ "unstable-options",
+ "--print",
+ "target-spec-json",
+ "--",
+ "-Z",
+ "unstable-options",
+ ])
.env("RUSTC_BOOTSTRAP", "1");
if let Some(target) = target {
cmd.args(["--target", target]);