1 files changed, 1 insertions, 1 deletions
diff --git a/src/libstd/sync/rwlock.rs b/src/libstd/sync/rwlock.rs
index e3db60cff84..ed3a3865a6c 100644
--- a/src/libstd/sync/rwlock.rs
+++ b/src/libstd/sync/rwlock.rs
@@ -597,7 +597,7 @@ mod tests {
             thread::spawn(move || {
                 let mut rng = rand::thread_rng();
                 for _ in 0..M {
-                    if rng.gen_weighted_bool(N) {
+                    if rng.gen_bool(1.0 / (N as f64)) {
                         drop(r.write().unwrap());
                     } else {
                         drop(r.read().unwrap());