diff --git a/src/if_cscope.c b/src/if_cscope.c
index b2a4ce1..b8fef28 100644
--- a/src/if_cscope.c
+++ b/src/if_cscope.c
@@ -2278,7 +2278,11 @@
 	/* Use sigaction() to limit the waiting time to two seconds. */
 	sigemptyset(&sa.sa_mask);
 	sa.sa_handler = sig_handler;
+#  ifdef SA_NODEFER
 	sa.sa_flags = SA_NODEFER;
+#  else
+	sa.sa_flags = 0;
+#  endif
 	sigaction(SIGALRM, &sa, &old);
 	alarm(2); /* 2 sec timeout */