--- screen-4.0.3/Makefile.in
+++ screen-4.0.3/Makefile.in
@@ -68,7 +68,7 @@
 	$(CC) $(LDFLAGS) -o $@ $(OFILES) $(LIBS)
 
 .c.o:
-	$(CC) -c -I. -I$(srcdir) $(M_CFLAGS) $(DEFS) $(OPTIONS) $(CFLAGS) $<
+	$(CC) -c -I. -I$(srcdir) $(M_CFLAGS) $(DEFS) $(OPTIONS) $(CPPFLAGS) $(CFLAGS) $<
 
 install_bin: .version screen
 	-if [ -f $(DESTDIR)$(bindir)/$(SCREEN) ] && [ ! -f $(DESTDIR)$(bindir)/$(SCREEN).old ]; \
@@ -122,7 +122,7 @@
 	sh $(srcdir)/tty.sh tty.c
 
 comm.h: comm.c comm.sh config.h
-	AWK=$(AWK) CC="$(CC) $(CFLAGS)" srcdir=${srcdir} sh $(srcdir)/comm.sh
+	AWK=$(AWK) CC="$(CC) $(CFLAGS) $(CPPFLAGS)" srcdir=${srcdir} sh $(srcdir)/comm.sh
 
 osdef.h: osdef.sh config.h osdef.h.in
 	CPP="$(CPP) $(CPPFLAGS)" srcdir=${srcdir} sh $(srcdir)/osdef.sh