# Make bison/lib.
-# Copyright (C) 2001, 2002, 2003, 2004, 2006 Free Software Foundation, Inc.
+# Copyright (C) 2001, 2002, 2003, 2004, 2006, 2008, 2009
+# Free Software Foundation, Inc.
# This program is free software: you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
include gnulib.mk
-AM_CFLAGS = $(WARN_CFLAGS)
+AM_CFLAGS += $(WARN_CFLAGS)
# Implementation of bitsets.
bitsets_sources = \