diff --git a/Makefile.am b/Makefile.am
index f4ed5e1d..85c2b4a0 100644
--- a/Makefile.am
+++ b/Makefile.am
@@ -15,7 +15,7 @@ EXTRA_DIST	= example.conf m4/gnulib-cache.m4 linux-usb-cgminer \
 
 SUBDIRS		= lib compat ccan
 
-INCLUDES	= $(PTHREAD_FLAGS) -fno-strict-aliasing $(JANSSON_INCLUDES) $(USB_FLAGS)
+AM_CPPFLAGS	= $(PTHREAD_FLAGS) -fno-strict-aliasing $(JANSSON_INCLUDES) $(USB_FLAGS)
 
 bin_PROGRAMS	= cgminer