fixed some build file flaws

m4/ax_check_sign.m4

@@ -0,0 +1,53 @@
+# ===========================================================================
+#       http://www.gnu.org/software/autoconf-archive/ax_check_sign.html
+# ===========================================================================
+#
+# SYNOPSIS
+#
+#   AX_CHECK_SIGN (TYPE, [ACTION-IF-SIGNED], [ACTION-IF-UNSIGNED], [INCLUDES])
+#
+# DESCRIPTION
+#
+#   Checks whether TYPE is signed or not. If no INCLUDES are specified, the
+#   default includes are used. If ACTION-IF-SIGNED is given, it is
+#   additional shell code to execute when the type is signed. If
+#   ACTION-IF-UNSIGNED is given, it is executed when the type is unsigned.
+#
+#   This macro assumes that the type exists. Therefore the existence of the
+#   type should be checked before calling this macro. For example:
+#
+#     AC_CHECK_HEADERS([wchar.h])
+#     AC_CHECK_TYPE([wchar_t],,[ AC_MSG_ERROR([Type wchar_t not found.]) ])
+#     AX_CHECK_SIGN([wchar_t],
+#       [ AC_DEFINE(WCHAR_T_SIGNED, 1, [Define if wchar_t is signed]) ],
+#       [ AC_DEFINE(WCHAR_T_UNSIGNED, 1, [Define if wchar_t is unsigned]) ], [
+#     #ifdef HAVE_WCHAR_H
+#     #include <wchar.h>
+#     #endif
+#     ])
+#
+# LICENSE
+#
+#   Copyright (c) 2008 Ville Laurikari <vl@iki.fi>
+#
+#   Copying and distribution of this file, with or without modification, are
+#   permitted in any medium without royalty provided the copyright notice
+#   and this notice are preserved. This file is offered as-is, without any
+#   warranty.
+
+#serial 6
+
+AC_DEFUN([AX_CHECK_SIGN], [
+ typename=`echo $1 | sed "s/@<:@^a-zA-Z0-9_@:>@/_/g"`
+ AC_CACHE_CHECK([whether $1 is signed], ax_cv_decl_${typename}_signed, [
+   AC_TRY_COMPILE([$4],
+     [ int foo @<:@ 1 - 2 * !((($1) -1) < 0) @:>@ ],
+     [ eval "ax_cv_decl_${typename}_signed=\"yes\"" ],
+     [ eval "ax_cv_decl_${typename}_signed=\"no\"" ])])
+ symbolname=`echo $1 | sed "s/@<:@^a-zA-Z0-9_@:>@/_/g" | tr "a-z" "A-Z"`
+ if eval "test \"\${ax_cv_decl_${typename}_signed}\" = \"yes\""; then
+   $2
+ elif eval "test \"\${ax_cv_decl_${typename}_signed}\" = \"no\""; then
+   $3
+ fi
+])dnl