From daeb68a579d0a0e8e3de0d1cd39c60c2d0a30a87 Mon Sep 17 00:00:00 2001
From: Ralf Jung <post@ralfj.de>
Date: Thu, 30 May 2024 09:05:03 +0200
Subject: [PATCH] make env/var test deterministic

---
 src/tools/miri/tests/pass/shims/env/var.rs | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/src/tools/miri/tests/pass/shims/env/var.rs b/src/tools/miri/tests/pass/shims/env/var.rs
index babaf00578a7..a576c1fc8bb8 100644
--- a/src/tools/miri/tests/pass/shims/env/var.rs
+++ b/src/tools/miri/tests/pass/shims/env/var.rs
@@ -1,3 +1,4 @@
+//@compile-flags: -Zmiri-preemption-rate=0
 use std::env;
 use std::thread;
 
@@ -26,6 +27,8 @@ fn main() {
     println!("{:#?}", env::vars().collect::<Vec<_>>());
 
     // Do things concurrently, to make sure there's no data race.
+    // We disable preemption to make sure the lock is not contended;
+    // that means we don't hit e.g. the futex codepath on Android (which we don't support).
     let t = thread::spawn(|| {
         env::set_var("MIRI_TEST", "42");
     });