--- np2/x11/configure.ac	2011/12/24 17:48:03	1.14
+++ np2/x11/configure.ac	2011/12/29 14:32:31	1.17
@@ -4,9 +4,9 @@ dnl
 
 dnl require autoconf 2.59
 AC_PREREQ(2.59)
-AC_REVISION($Revision: 1.14 $)
+AC_REVISION($Revision: 1.17 $)
 
-AC_INIT(Xnp2,0.83-20111224,nonakap@gmail.com,xnp2)
+AC_INIT(Xnp2,0.83-20111229,nonakap@gmail.com,xnp2)
 AM_INIT_AUTOMAKE([no-define no-dist no-installinfo subdir-objects])
 AC_CONFIG_SRCDIR([../np2ver.h])
 AC_CONFIG_HEADERS(config.h)
@@ -97,6 +97,9 @@ AC_ARG_ENABLE(ia32,
 AC_ARG_ENABLE(debug,
   AC_HELP_STRING([--enable-debug],[Enable debugging [[default=no]]]),,
   [enable_debug="no"])
+AC_ARG_ENABLE(warning,
+  AC_HELP_STRING([--enable-warning],[Enable warning [[default=no]]]),,
+  [enable_warning="no"])
 
 dnl
 dnl Checks for GTK+
@@ -162,16 +165,27 @@ dnl
 AC_MSG_CHECKING([whether to enable debugging])
 if test x"$enable_debug" = "xyes"; then
   CFLAGS="$CFLAGS -DDEBUG -g -O0"
-  CFLAGS="$CFLAGS -Wall -Wcast-align"
-  CFLAGS="$CFLAGS -Wwrite-strings -Wstrict-prototypes -Wmissing-prototypes -Wmissing-declarations"
-  CFLAGS="$CFLAGS -Wextra -Wno-sign-compare -Wno-unused-parameter -Wno-missing-field-initializers"
   CFLAGS="$CFLAGS -Wstack-protector -fstack-protector --param ssp-buffer-size=1"
+  enable_warning=yes
 else
   CFLAGS="$CFLAGS -DNDEBUG"
 fi
 AC_MSG_RESULT($enable_debug)
 
 dnl
+dnl Checks for warning
+dnl
+AC_MSG_CHECKING([whether to enable warning])
+if test x"$enable_warning" = "xyes"; then
+  CFLAGS="$CFLAGS -Wall -Wstrict-prototypes -Wmissing-prototypes -Wpointer-arith"
+  CFLAGS="$CFLAGS -Wreturn-type -Wswitch -Wshadow"
+  CFLAGS="$CFLAGS -Wcast-qual -Wwrite-strings"
+  CFLAGS="$CFLAGS -Wextra -Wno-unused-parameter"
+  CFLAGS="$CFLAGS -Wformat=2"
+fi
+AC_MSG_RESULT($enable_warning)
+
+dnl
 dnl Checks for Xnp2 version
 dnl
 NP2VER_X11=`echo $PACKAGE_VERSION | $AWK 'BEGIN {FS="-"} NF==2 {print $2}'`