encoding/gob: fix 386 build

LGTM=ruiu
R=golang-codereviews, ruiu
CC=golang-codereviews
https://golang.org/cl/146320043

diff --git a/src/encoding/gob/decode.go b/src/encoding/gob/decode.go
index 502209a8a8085b78e60dd2fb721d83f37123bc6a..6a9213fb3cb6c7f8dcb21efafaee1de4006ca1d3 100644 (file)
--- a/src/encoding/gob/decode.go
+++ b/src/encoding/gob/decode.go
@@ -536,18 +536,15 @@ func (dec *Decoder) ignoreMap(state *decoderState, keyOp, elemOp decOp) {
 // Slices are encoded as an unsigned length followed by the elements.
 func (dec *Decoder) decodeSlice(state *decoderState, value reflect.Value, elemOp decOp, ovfl error) {
        u := state.decodeUint()
-       n := int(u)
-       if n < 0 || uint64(n) != u {
-               // We don't check n against buffer length here because if it's a slice
-               // of interfaces, there will be buffer reloads.
-               errorf("length of %s is negative (%d bytes)", value.Type(), u)
-       }
        typ := value.Type()
        size := uint64(typ.Elem().Size())
-       // Take care with overflow in this calculation.
        nBytes := u * size
-       if nBytes > tooBig || (size > 0 && nBytes/size != u) {
-               errorf("%s slice too big: %d elements of %d bytes", typ.Elem(), n, size)
+       n := int(u)
+       // Take care with overflow in this calculation.
+       if n < 0 || uint64(n) != u || nBytes > tooBig || (size > 0 && nBytes/size != u) {
+               // We don't check n against buffer length here because if it's a slice
+               // of interfaces, there will be buffer reloads.
+               errorf("%s slice too big: %d elements of %d bytes", typ.Elem(), u, size)
        }
        if value.Cap() < n {
                value.Set(reflect.MakeSlice(typ, n, n))