From 663c6633e39d194bed0048df1e8ea5b60ef00e73 Mon Sep 17 00:00:00 2001
From: Ralf Jung <post@ralfj.de>
Date: Tue, 15 Aug 2023 09:44:47 +0200
Subject: [PATCH] don't run build probes in rustc bootstrap

---
 build.rs | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/build.rs b/build.rs
index de94535..8456a7d 100644
--- a/build.rs
+++ b/build.rs
@@ -68,6 +68,14 @@ fn main() {
 }
 
 fn compile_probe() -> Option<ExitStatus> {
+    if env::var_os("RUSTC_STAGE").is_some() {
+        // We are running inside rustc bootstrap. This is a highly non-standard environment with
+        // issues such as <https://github.com/rust-lang/cargo/issues/11138> and
+        // <https://github.com/rust-lang/rust/issues/114839>. Let's just not use nightly features
+        // here.
+        return None;
+    }
+
     let rustc = env::var_os("RUSTC")?;
     let out_dir = env::var_os("OUT_DIR")?;
     let probefile = Path::new(&out_dir).join("probe.rs");