diff options
Diffstat (limited to 'src/pkg/math/big/int.go')
| -rw-r--r-- | src/pkg/math/big/int.go | 18 |
1 files changed, 12 insertions, 6 deletions
diff --git a/src/pkg/math/big/int.go b/src/pkg/math/big/int.go index d1b5602d6..7bbb152d7 100644 --- a/src/pkg/math/big/int.go +++ b/src/pkg/math/big/int.go @@ -563,13 +563,13 @@ func (z *Int) SetBytes(buf []byte) *Int { return z } -// Bytes returns the absolute value of z as a big-endian byte slice. +// Bytes returns the absolute value of x as a big-endian byte slice. func (x *Int) Bytes() []byte { buf := make([]byte, len(x.abs)*_S) return buf[x.abs.bytes(buf):] } -// BitLen returns the length of the absolute value of z in bits. +// BitLen returns the length of the absolute value of x in bits. // The bit length of 0 is 0. func (x *Int) BitLen() int { return x.abs.bitLen() @@ -703,14 +703,15 @@ func (z *Int) binaryGCD(a, b *Int) *Int { // reduce t t.Rsh(t, t.abs.trailingZeroBits()) if t.neg { - v.Neg(t) + v, t = t, v + v.neg = len(v.abs) > 0 && !v.neg // 0 has no sign } else { - u.Set(t) + u, t = t, u } t.Sub(u, v) } - return u.Lsh(u, k) + return z.Lsh(u, k) } // ProbablyPrime performs n Miller-Rabin tests to check whether x is prime. @@ -951,6 +952,9 @@ const intGobVersion byte = 1 // GobEncode implements the gob.GobEncoder interface. func (x *Int) GobEncode() ([]byte, error) { + if x == nil { + return nil, nil + } buf := make([]byte, 1+len(x.abs)*_S) // extra byte for version and sign bit i := x.abs.bytes(buf) - 1 // i >= 0 b := intGobVersion << 1 // make space for sign bit @@ -964,7 +968,9 @@ func (x *Int) GobEncode() ([]byte, error) { // GobDecode implements the gob.GobDecoder interface. func (z *Int) GobDecode(buf []byte) error { if len(buf) == 0 { - return errors.New("Int.GobDecode: no data") + // Other side sent a nil or default value. + *z = Int{} + return nil } b := buf[0] if b>>1 != intGobVersion { |