addend = n << bshift;
addend = (BignumDblInt)n << bshift;
static void internal_add_shifted(BignumInt *number,				 unsigned n, int shift){    int word = 1 + (shift / BIGNUM_INT_BITS);    int bshift = shift % BIGNUM_INT_BITS;    BignumDblInt addend;    addend = n << bshift;    while (addend) {	addend += number[word];	number[word] = (BignumInt) addend & BIGNUM_INT_MASK;	addend >>= BIGNUM_INT_BITS;	word++;    }}