-AC_DEFUN([AC_MBSTATE_T],
- [
- AC_CHECK_HEADERS(stdlib.h)
-
- AC_CACHE_CHECK([for mbstate_t], ac_cv_type_mbstate_t,
- [AC_TRY_COMPILE([
-#if HAVE_STDLIB_H
-# include <stdlib.h>
-#endif
-#include <wchar.h>],
- [mbstate_t x; return sizeof x;],
- ac_cv_type_mbstate_t=yes,
- ac_cv_type_mbstate_t=no)])
- if test $ac_cv_type_mbstate_t = no; then
- AC_DEFINE(mbstate_t, int,
- [Define to a type if <wchar.h> does not define.])
- fi])
+ AC_CACHE_CHECK([for mbstate_t], [ac_cv_type_mbstate_t],
+ [AC_COMPILE_IFELSE(
+ [AC_LANG_PROGRAM(
+ [AC_INCLUDES_DEFAULT[
+/* Tru64 with Desktop Toolkit C has a bug: <stdio.h> must be included before
+ <wchar.h>.
+ BSD/OS 4.0.1 has a bug: <stddef.h>, <stdio.h> and <time.h> must be
+ included before <wchar.h>. */
+#include <stddef.h>
+#include <stdio.h>
+#include <time.h>
+#include <wchar.h>]],
+ [[mbstate_t x; return sizeof x;]])],
+ [ac_cv_type_mbstate_t=yes],
+ [ac_cv_type_mbstate_t=no])])
+ if test $ac_cv_type_mbstate_t = yes; then
+ AC_DEFINE([HAVE_MBSTATE_T], [1],
+ [Define to 1 if <wchar.h> declares mbstate_t.])
+ else
+ AC_DEFINE([mbstate_t], [int],
+ [Define to a type if <wchar.h> does not define.])
+ fi
+])