char *outbuf = (char *) (pwc ?: buf);
unsigned char *outbuf = (unsigned char *) (pwc ?: buf);
__mbrtowc (wchar_t *pwc, const char *s, size_t n, mbstate_t *ps){  wchar_t buf[1];  struct __gconv_step_data data;  int status;  size_t result;  size_t dummy;  const unsigned char *inbuf, *endbuf;  char *outbuf = (char *) (pwc ?: buf);  const struct gconv_fcts *fcts;  /* Set information for this step.  */  data.__invocation_counter = 0;  data.__internal_use = 1;  data.__flags = __GCONV_IS_LAST;  data.__statep = ps ?: &state;  data.__trans = NULL;  /* A first special case is if S is NULL.  This means put PS in the     initial state.  */  if (s == NULL)    {      outbuf = (char *) buf;      s = "";      n = 1;    }  /* Tell where we want the result.  */  data.__outbuf = outbuf;  data.__outbufend = outbuf + sizeof (wchar_t);  /* Get the conversion functions.  */  fcts = get_gconv_fcts (_NL_CURRENT_DATA (LC_CTYPE));  /* Do a normal conversion.  */  inbuf = (const unsigned char *) s;  endbuf = inbuf + n;  if (__builtin_expect (endbuf < inbuf, 0))    endbuf = (const unsigned char *) ~(uintptr_t) 0;  status = DL_CALL_FCT (fcts->towc->__fct,			(fcts->towc, &data, &inbuf, endbuf,			 NULL, &dummy, 0, 1));  /* There must not be any problems with the conversion but illegal input     characters.  The output buffer must be large enough, otherwise the     definition of MB_CUR_MAX is not correct.  All the other possible     errors also must not happen.  */  assert (status == __GCONV_OK || status == __GCONV_EMPTY_INPUT	  || status == __GCONV_ILLEGAL_INPUT	  || status == __GCONV_INCOMPLETE_INPUT	  || status == __GCONV_FULL_OUTPUT);  if (status == __GCONV_OK || status == __GCONV_EMPTY_INPUT      || status == __GCONV_FULL_OUTPUT)    {      if (data.__outbuf != (unsigned char *) outbuf	  && *(wchar_t *) outbuf == L'\0')	{	  /* The converted character is the NUL character.  */	  assert (__mbsinit (data.__statep));	  result = 0;	}      else	result = inbuf - (const unsigned char *) s;    }  else if (status == __GCONV_INCOMPLETE_INPUT)    result = (size_t) -2;  else    {      result = (size_t) -1;      __set_errno (EILSEQ);    }  return result;}