From 88e27b8df27d0aaa1ade562b01224cdfd6ead8d8 Mon Sep 17 00:00:00 2001
From: Jacob Hoffman-Andrews <github@hoffman-andrews.com>
Date: Fri, 31 Mar 2023 23:07:51 -0700
Subject: [PATCH] build.rs: print rustc stderr if exit status != 0

---
 build.rs | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/build.rs b/build.rs
index e60672a76133b..9aa8e4a7e96fd 100644
--- a/build.rs
+++ b/build.rs
@@ -181,6 +181,11 @@ fn rustc_minor_nightly() -> (u32, bool) {
         .output()
         .ok()
         .expect("Failed to get rustc version");
+    if !output.status.success() {
+        let stderr = std::string::String::from_utf8_lossy(output.stderr.as_slice());
+        eprintln!("failed to run rustc: {stderr}");
+    }
+
     let version = otry!(str::from_utf8(&output.stdout).ok());
     let mut pieces = version.split('.');