diff --git a/libfprint/Makefile.am b/libfprint/Makefile.am
index 844b09ed..056eb676 100644
--- a/libfprint/Makefile.am
+++ b/libfprint/Makefile.am
@@ -10,8 +10,8 @@ AES4000_SRC = drivers/aes4000.c
 FDU2000_SRC = drivers/fdu2000.c
 VCOM5S_SRC = drivers/vcom5s.c
 
-DRIVER_SRC = ""
-OTHER_SRC = ""
+DRIVER_SRC =
+OTHER_SRC =
 
 NBIS_SRC = \
 	nbis/include/bozorth.h \