diff --git a/src/crypto/internal/edwards25519/scalarmult.go b/src/crypto/internal/edwards25519/scalarmult.go
index f7ca3cef993..3992dc90828 100644
--- a/src/crypto/internal/edwards25519/scalarmult.go
+++ b/src/crypto/internal/edwards25519/scalarmult.go
@@ -167,8 +167,8 @@ func (v *Point) VarTimeDoubleScalarBaseMult(a *Scalar, A *Point, b *Scalar) *Poi
 
 	// Find the first nonzero coefficient.
 	i := 255
-	for j := i; j >= 0; j-- {
-		if aNaf[j] != 0 || bNaf[j] != 0 {
+	for ; i >= 0; i-- {
+		if aNaf[i] != 0 || bNaf[i] != 0 {
 			break
 		}
 	}