mbstate_t.m4

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# mbstate_t.m4 serial 9
dnl Copyright (C) 2000, 2001, 2002 Free Software Foundation, Inc.
dnl This file is free software; the Free Software Foundation
dnl gives unlimited permission to copy and/or distribute it,
dnl with or without modifications, as long as this notice is preserved.

# From Paul Eggert.

# BeOS 5 has <wchar.h> but does not define mbstate_t,
# so you can't declare an object of that type.
# Check for this incompatibility with Standard C.

# AC_TYPE_MBSTATE_T
# -----------------
AC_DEFUN([AC_TYPE_MBSTATE_T],
  [AC_CACHE_CHECK([for mbstate_t], ac_cv_type_mbstate_t,
     [AC_COMPILE_IFELSE(
	[AC_LANG_PROGRAM(
	   [AC_INCLUDES_DEFAULT
#	    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])