diff --git a/test/zdtm/static/zombie00.c b/test/zdtm/static/zombie00.c
index 8ee9c0765..df12a7046 100644
--- a/test/zdtm/static/zombie00.c
+++ b/test/zdtm/static/zombie00.c
@@ -49,7 +49,7 @@ int main(int argc, char ** argv)
 			if (zombie[i].exited)
 				_exit(zombie[i].exitcode);
 			else if (zombie[i].exitcode == SIGSEGV)
-				*(int *)NULL = 0;
+				*(volatile int *)NULL = 0;
 			else
 				kill(getpid(), zombie[i].exitcode);