diff --git a/test/osal-unix.cc b/test/osal-unix.cc
index 757c8583..a85ce32a 100644
--- a/test/osal-unix.cc
+++ b/test/osal-unix.cc
@@ -23,6 +23,8 @@
 #include <sys/wait.h>
 #include <unistd.h>
 
+#include <atomic>
+
 #ifndef MDBX_LOCKING
 #error "Opps, MDBX_LOCKING is undefined!"
 #endif
@@ -307,14 +309,14 @@ bool actor_config::osal_deserialize(const char *str, const char *end,
 
 static pid_t overlord_pid;
 
-static volatile sig_atomic_t sigusr1_head, sigusr2_head;
+static std::atomic<int> sigusr1_head, sigusr2_head;
 static void handler_SIGUSR(int signum) {
   switch (signum) {
   case SIGUSR1:
-    sigusr1_head += 1;
+    ++sigusr1_head;
     return;
   case SIGUSR2:
-    sigusr2_head += 1;
+    ++sigusr2_head;
     return;
   default:
     abort();
@@ -335,10 +337,10 @@ bool osal_progress_push(bool active) {
 
 static std::unordered_map<pid_t, actor_status> childs;
 
-static volatile sig_atomic_t sigalarm_head;
+static std::atomic<int> sigalarm_head;
 static void handler_SIGCHLD(int signum) {
   if (signum == SIGALRM)
-    sigalarm_head += 1;
+    ++sigalarm_head;
 }
 
 mdbx_pid_t osal_getpid(void) { return getpid(); }