From 6b350f42830f5a1b2f8cea3a9034147a4ef840ef Mon Sep 17 00:00:00 2001
From: "copilot-swe-agent[bot]" <198982749+Copilot@users.noreply.github.com>
Date: Mon, 21 Sep 2026 03:22:06 +0000
Subject: [PATCH 1/2] Initial plan


From c90785642030ce82eadaf8ca7f8b5b0b08e98158 Mon Sep 17 00:00:00 2001
From: "copilot-swe-agent[bot]" <198982749+Copilot@users.noreply.github.com>
Date: Mon, 21 Sep 2026 03:24:50 +0000
Subject: [PATCH 2/2] Probe CUDA_PATH for Windows LLVM

Co-authored-by: LegNeato <368904+LegNeato@users.noreply.github.com>
---
 crates/rustc_codegen_nvvm/build.rs | 21 +++++++++++++++------
 1 file changed, 15 insertions(+), 6 deletions(-)

diff --git a/crates/rustc_codegen_nvvm/build.rs b/crates/rustc_codegen_nvvm/build.rs
index 973c3499..f5b76e86 100644
--- a/crates/rustc_codegen_nvvm/build.rs
+++ b/crates/rustc_codegen_nvvm/build.rs
@@ -38,6 +38,12 @@ static PREBUILT_LLVM_URL_LLVM7: &str =
     "https://github.com/rust-gpu/rustc_codegen_nvvm-llvm/releases/download/llvm-7.1.0/";
 static PREBUILT_LLVM_URL_LLVM19: &str =
     "https://github.com/rust-gpu/rustc_codegen_nvvm-llvm/releases/download/llvm-19.1.7/";
+static CUDA_ROOT_ENVS: &[&str] = &[
+    "CUDA_HOME",
+    "CUDA_PATH",
+    "CUDA_ROOT",
+    "CUDA_TOOLKIT_ROOT_DIR",
+];
 
 fn main() {
     let flavor = if llvm19_enabled() { &LLVM19 } else { &LLVM7 };
@@ -174,12 +180,15 @@ fn find_llvm_config(target: &str, flavor: &LlvmFlavor) -> PathBuf {
 
         candidates.push(PathBuf::from(flavor.default_binary));
 
-        if flavor.probe_cuda_home
-            && let Some(cuda_home) = tracked_env_var_os("CUDA_HOME")
-        {
-            let cuda_home = PathBuf::from(cuda_home);
-            candidates.push(cuda_home.join("nvvm").join("bin").join("llvm-config"));
-            candidates.push(cuda_home.join("bin").join("llvm-config"));
+        if flavor.probe_cuda_home {
+            for cuda_root in CUDA_ROOT_ENVS
+                .iter()
+                .filter_map(tracked_env_var_os)
+                .map(PathBuf::from)
+            {
+                candidates.push(cuda_root.join("nvvm").join("bin").join("llvm-config"));
+                candidates.push(cuda_root.join("bin").join("llvm-config"));
+            }
         }
 
         for candidate in &candidates {