check if it's rust-lang/rust CI job in llvm::is_ci_llvm_modified

src/bootstrap/src/core/build_steps/llvm.rs

@@ -241,7 +241,7 @@ pub(crate) fn is_ci_llvm_available(config: &Config, asserts: bool) -> bool {
 
 /// Returns true if we're running in CI with modified LLVM (and thus can't download it)
 pub(crate) fn is_ci_llvm_modified(config: &Config) -> bool {
-    CiEnv::is_ci() && config.rust_info.is_managed_git_subrepository() && {
+    CiEnv::is_rust_lang_managed_ci_job() && config.rust_info.is_managed_git_subrepository() && {
         // We assume we have access to git, so it's okay to unconditionally pass
         // `true` here.
         let llvm_sha = detect_llvm_sha(config, true);

src/bootstrap/src/core/config/config.rs

@@ -342,6 +342,15 @@ pub struct Config {
     pub out: PathBuf,
     pub rust_info: channel::GitInfo,
 
+    pub cargo_info: channel::GitInfo,
+    pub rust_analyzer_info: channel::GitInfo,
+    pub clippy_info: channel::GitInfo,
+    pub miri_info: channel::GitInfo,
+    pub rustfmt_info: channel::GitInfo,
+    pub enzyme_info: channel::GitInfo,
+    pub in_tree_llvm_info: channel::GitInfo,
+    pub in_tree_gcc_info: channel::GitInfo,
+
     // These are either the stage0 downloaded binaries or the locally installed ones.
     pub initial_cargo: PathBuf,
     pub initial_rustc: PathBuf,
@@ -1797,6 +1806,19 @@ impl Config {
         config.omit_git_hash = omit_git_hash.unwrap_or(default);
         config.rust_info = GitInfo::new(config.omit_git_hash, &config.src);
 
+        config.cargo_info = GitInfo::new(config.omit_git_hash, &config.src.join("src/tools/cargo"));
+        config.rust_analyzer_info =
+            GitInfo::new(config.omit_git_hash, &config.src.join("src/tools/rust-analyzer"));
+        config.clippy_info =
+            GitInfo::new(config.omit_git_hash, &config.src.join("src/tools/clippy"));
+        config.miri_info = GitInfo::new(config.omit_git_hash, &config.src.join("src/tools/miri"));
+        config.rustfmt_info =
+            GitInfo::new(config.omit_git_hash, &config.src.join("src/tools/rustfmt"));
+        config.enzyme_info =
+            GitInfo::new(config.omit_git_hash, &config.src.join("src/tools/enzyme"));
+        config.in_tree_llvm_info = GitInfo::new(false, &config.src.join("src/llvm-project"));
+        config.in_tree_gcc_info = GitInfo::new(false, &config.src.join("src/gcc"));
+
         // We need to override `rust.channel` if it's manually specified when using the CI rustc.
         // This is because if the compiler uses a different channel than the one specified in config.toml,
         // tests may fail due to using a different channel than the one used by the compiler during tests.

src/bootstrap/src/lib.rs

@@ -305,18 +305,15 @@ impl Build {
         #[cfg(not(unix))]
         let is_sudo = false;
 
-        let omit_git_hash = config.omit_git_hash;
-        let rust_info = GitInfo::new(omit_git_hash, &src);
-        let cargo_info = GitInfo::new(omit_git_hash, &src.join("src/tools/cargo"));
-        let rust_analyzer_info = GitInfo::new(omit_git_hash, &src.join("src/tools/rust-analyzer"));
-        let clippy_info = GitInfo::new(omit_git_hash, &src.join("src/tools/clippy"));
-        let miri_info = GitInfo::new(omit_git_hash, &src.join("src/tools/miri"));
-        let rustfmt_info = GitInfo::new(omit_git_hash, &src.join("src/tools/rustfmt"));
-        let enzyme_info = GitInfo::new(omit_git_hash, &src.join("src/tools/enzyme"));
-
-        // we always try to use git for LLVM builds
-        let in_tree_llvm_info = GitInfo::new(false, &src.join("src/llvm-project"));
-        let in_tree_gcc_info = GitInfo::new(false, &src.join("src/gcc"));
+        let rust_info = config.rust_info.clone();
+        let cargo_info = config.cargo_info.clone();
+        let rust_analyzer_info = config.rust_analyzer_info.clone();
+        let clippy_info = config.clippy_info.clone();
+        let miri_info = config.miri_info.clone();
+        let rustfmt_info = config.rustfmt_info.clone();
+        let enzyme_info = config.enzyme_info.clone();
+        let in_tree_llvm_info = config.in_tree_llvm_info.clone();
+        let in_tree_gcc_info = config.in_tree_gcc_info.clone();
 
         let initial_target_libdir_str = if config.dry_run() {
             "/dummy/lib/path/to/lib/".to_string()

src/tools/build_helper/src/ci.rs

@@ -19,6 +19,15 @@ impl CiEnv {
     pub fn is_ci() -> bool {
         Self::current() != CiEnv::None
     }
+
+    /// Checks if running in rust-lang/rust managed CI job.
+    pub fn is_rust_lang_managed_ci_job() -> bool {
+        Self::is_ci()
+            // If both are present, we can assume it's an upstream CI job
+            // as they are always set unconditionally.
+            && std::env::var_os("CI_JOB_NAME").is_some()
+            && std::env::var_os("TOOLSTATE_REPO").is_some()
+    }
 }
 
 pub mod gha {