diff -ru src.orig/pppdump/Makefile.linux src/pppdump/Makefile.linux
--- src.orig/pppdump/Makefile.linux	2014-07-28 18:29:24.315572317 +0200
+++ src/pppdump/Makefile.linux	2014-07-28 18:29:35.059572592 +0200
@@ -2,7 +2,8 @@
 BINDIR = $(DESTDIR)/sbin
 MANDIR = $(DESTDIR)/share/man/man8
 
-CFLAGS= -O -I../include/net
+COPTS = -O
+CFLAGS= $(COPTS) -I../include/net
 OBJS = pppdump.o bsd-comp.o deflate.o zlib.o
 
 INSTALL= install