Conservatively serialize nearly all upcalls. Successfuly ran make check with RUST_THREADS=8, so we're probably fairly safe now. In the future we can relax the synchronization to get better performance.

1 files changed, 3 insertions, 1 deletions

diff --git a/src/rt/sync/lock_and_signal.cpp b/src/rt/sync/lock_and_signal.cpp
index 337a1efa4bc..6934a796521 100644
--- a/src/rt/sync/lock_and_signal.cpp
+++ b/src/rt/sync/lock_and_signal.cpp
@@ -21,7 +21,9 @@ lock_and_signal::lock_and_signal() {
 }
 
 #else
-lock_and_signal::lock_and_signal() {
+lock_and_signal::lock_and_signal() 
+    : _locked(false)
+{
     CHECKED(pthread_cond_init(&_cond, NULL));
     CHECKED(pthread_mutex_init(&_mutex, NULL));
 }