big: fix build - start with zero in scanN

R=gri, eds
CC=golang-dev
https://golang.org/cl/947042

diff --git a/src/pkg/big/nat.go b/src/pkg/big/nat.go
index 6c7e6e722d9afb8d404c63a3858dc0874df65343..8843d435494b78af996e6293ca85c63d5c91ba48 100644 (file)
--- a/src/pkg/big/nat.go
+++ b/src/pkg/big/nat.go
@@ -432,7 +432,7 @@ func scanN(z []Word, s string, base int) ([]Word, int, int) {
        }
 
        // convert string
-       z = makeN(z, len(z), false)
+       z = z[0:0]
        for ; i < n; i++ {
                d := hexValue(s[i])
                if 0 <= d && d < base {