--- Makefile.orig	2019-04-08 08:32:00 UTC
+++ Makefile
@@ -1,4 +1,4 @@
-CFLAGS = -std=c99 -O3
+CFLAGS += -std=c99 -D__BSD_VISIBLE
 
 LIBS   = -lpthread
 ifeq ($(OPENSSL),1)