--- configure.in.orig	2011-08-11 12:02:41.000000000 +0900
+++ configure.in	2012-08-25 21:35:30.000000000 +0900
@@ -30,7 +30,6 @@
 AM_INIT_AUTOMAKE(crfsuite, 0.12)
 AC_CONFIG_HEADERS(config.h)
 AM_MAINTAINER_MODE
-AM_C_PROTOTYPES
 
 
 dnl ------------------------------------------------------------------