if (__builtin_expect (dstlen < len * sizeof (wchar_t), 0))
if (__builtin_expect (dstlen < len, 0))
__mbsrtowcs_chk (wchar_t *dst, __const char **src, size_t len,		 mbstate_t *ps, size_t dstlen){  if (__builtin_expect (dstlen < len * sizeof (wchar_t), 0))    __chk_fail ();  return __mbsrtowcs (dst, src, len, ps);}