diff --git a/src/Makefile.am b/src/Makefile.am
index b48ed75..d6e3e86 100644
--- a/src/Makefile.am
+++ b/src/Makefile.am
@@ -12,17 +12,17 @@ libbip_a_SOURCES = conf.y lex.l \
 	tuple.h \
 	util.c util.h
 
-libbip_a_CFLAGS = ${OPENSSL_CFLAGS}
+libbip_a_CFLAGS = ${OPENSSL_CFLAGS} $(AM_CFLAGS)
 
 bin_PROGRAMS = bip bipmkpw
 
 bip_SOURCES = bip_main.c
-bip_CFLAGS = ${OPENSSL_CFLAGS}
+bip_CFLAGS = ${OPENSSL_CFLAGS} $(AM_CFLAGS)
 bip_LDADD = libbip.a ${OPENSSL_LIBS}
 
 
 bipmkpw_SOURCES = bipmkpw.c md5.c util.c
-bipmkpw_CFLAGS = ${OPENSSL_CFLAGS}
+bipmkpw_CFLAGS = ${OPENSSL_CFLAGS} $(AM_CFLAGS)
 AM_YFLAGS= -d
 BUILT_SOURCES = conf.c conf.h lex.c