-AC_DEFUN(AC_MBSTATE_T_OBJECT,
- [AC_CACHE_CHECK([for mbstate_t object type], ac_cv_type_mbstate_t_object,
- [AC_TRY_COMPILE([#include <wchar.h>],
+# Include stdlib.h first, because otherwise this test would fail on Linux
+# (at least glibc-2.1.3) because the "_XOPEN_SOURCE 500" definition elicits
+# a syntax error in wchar.h due to the use of undefined __int32_t.
+
+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>],