diff --git a/server/mpm_unix.c b/server/mpm_unix.c
index b38df4ceee..d3137776c3 100644
--- a/server/mpm_unix.c
+++ b/server/mpm_unix.c
@@ -604,7 +604,7 @@ void ap_mpm_pod_killpg(ap_pod_t *pod, int num)
     }
 }
 
-static const char *dash_k_arg;
+static const char *dash_k_arg = NULL;
 
 static int send_signal(pid_t pid, int sig)
 {