Always build with DEBUG and enable assertions.

configure

@@ -200,9 +200,10 @@ fi
 if [ -n "$DEBUG" -a "$DEBUG" != no -a "$DEBUG" != false ]; then
 	echo "Building with debugging symbols."
 	echo "CFLAGS +=	-g" >>$CONFIG_MK
-	echo "CPPFLAGS +=	-DDEBUG" >>$CONFIG_MK
 fi
 
+echo "CPPFLAGS +=	-DDEBUG" >>$CONFIG_MK
+
 case "$OS" in
 linux)
 	echo "CPPFLAGS += 	-D_XOPEN_SOURCE=700" >>$CONFIG_MK