Fix cargo-gpu in build script failing when called by Miri or Clippy (#101)

* Remove `RUSTC_WRAPPER` env

* use new CargoCmd from spirv-builder to handle env vars centrally

* Update spirv-builder

---------

Co-authored-by: Firestar99 <[email protected]>

Author: tuguzT

Cargo.lock

@@ -13,7 +13,7 @@ exclude = [
 resolver = "2"
 
 [workspace.dependencies]
-spirv-builder = { git = "https://github.com/Rust-GPU/rust-gpu", rev = "e6d017d5504c4441a84edcc27f4eca61de6fc8cf", default-features = false }
+spirv-builder = { git = "https://github.com/Rust-GPU/rust-gpu", rev = "3e89e6cc7b32b51db51d75b5f558ccd7ecf5b850", default-features = false }
 anyhow = "1.0.94"
 clap = { version = "4.5.37", features = ["derive"] }
 crossterm = "0.28.1"

Cargo.toml

@@ -7,7 +7,6 @@ use crate::target_specs::update_target_specs_files;
 use crate::{cache_dir, spirv_source::SpirvSource};
 use anyhow::Context as _;
 use spirv_builder::SpirvBuilder;
-use std::env;
 use std::path::{Path, PathBuf};
 
 /// Represents a functional backend installation, whether it was cached or just installed.
@@ -279,8 +278,8 @@ package = "rustc_codegen_spirv"
                     .context("remove Cargo.lock")?;
             }
 
-            crate::user_output!("Compiling `rustc_codegen_spirv` from source {}\n", source,);
-            let mut cargo = std::process::Command::new("cargo");
+            crate::user_output!("Compiling `rustc_codegen_spirv` from source {}\n", source);
+            let mut cargo = spirv_builder::cargo_cmd::CargoCmd::new();
             cargo
                 .current_dir(&install_dir)
                 .arg(format!("+{toolchain_channel}"))
@@ -289,23 +288,7 @@ package = "rustc_codegen_spirv"
                 cargo.args(["-p", "rustc_codegen_spirv", "--lib"]);
             }
 
-            // Clear Cargo environment variables that we don't want to leak into the
-            // inner invocation of Cargo and mess with our `rustc_codegen_spirv` build.
-            for (key, _) in env::vars_os() {
-                let remove = key.to_str().is_some_and(|st| {
-                    st.starts_with("CARGO_FEATURES_") || st.starts_with("CARGO_CFG_")
-                });
-                if remove {
-                    cargo.env_remove(key);
-                }
-            }
-            cargo
-                .env_remove("RUSTC")
-                .env_remove("RUSTFLAGS")
-                // ignore any externally supplied target dir, we want to build it in our cache dir
-                .env_remove("CARGO_TARGET_DIR");
-
-            log::debug!("building artifacts with `{cargo:?}`");
+            log::debug!("building artifacts with `{cargo}`");
             cargo
                 .stdout(std::process::Stdio::inherit())
                 .stderr(std::process::Stdio::inherit())