diff --git a/Makefile b/Makefile
index 691254f0..b51e2b7b 100755
--- a/Makefile
+++ b/Makefile
@@ -30,6 +30,7 @@ CFLAGS += \
 	-std=c99 \
 	-W \
 	-Wall \
+	-D_BSD_SOURCE \
 	-D_DEFAULT_SOURCE \
 	-Wp,-MMD,$(dir $@).$(notdir $@).d \
 	-Wp,-MT,$@ \