int status = TCL_OK;	/* Status to return to caller. */
    char d = 0;			/* Last hexadecimal digit scanned; initialized
				 * to avoid a compiler warning. */
    int shift = 0;		/* Amount to shift when accumulating binary */
    mp_err err = MP_OKAY;
    int under = 0;              /* Flag trailing '_' as error if true once
				 * number is accepted. */
    

#define ALL_BITS	((Tcl_WideUInt)-1)
#define MOST_BITS	(ALL_BITS >> 1)

    /*
     * Initialize bytes to start of the object's string rep if the caller
     * didn't pass anything else.
     */

	status = TCL_ERROR;
	if (endPtrPtr != NULL) {
	    *endPtrPtr = p;
	}
    } else {
	/*
	 * Back up to the last accepting state in the lexer.  
	 * Back up to the last accepting state in the lexer.
	 * If the last char seen is the numeric whitespace character '_',
	 * backup to that.
	 */

	p = under ? acceptPoint-1 : acceptPoint;
	len = under ? acceptLen-1 : acceptLen;