diff --git a/sys_exec.go b/sys_exec.go
index 1c8e40e4..8a7c5784 100644
--- a/sys_exec.go
+++ b/sys_exec.go
@@ -94,8 +94,10 @@ func readv(fd int, bs [][]byte, ivs []syscall.Iovec) (n int, err error) {
 }
 
 // TODO: read from sysconf(_SC_IOV_MAX)? The Linux default is
-//  1024 and this seems conservative enough for now. Darwin's
-//  UIO_MAXIOV also seems to be 1024.
+//
+//	1024 and this seems conservative enough for now. Darwin's
+//	UIO_MAXIOV also seems to be 1024.
+//
 // iovecs limit length to 2GB(2^31)
 func iovecs(bs [][]byte, ivs []syscall.Iovec) (iovLen int) {
 	totalLen := 0
diff --git a/sys_exec_test.go b/sys_exec_test.go
index 54398df1..f35bb6e0 100644
--- a/sys_exec_test.go
+++ b/sys_exec_test.go
@@ -105,18 +105,23 @@ func TestReadv(t *testing.T) {
 	w3, _ := syscall.Write(w, vs[2])
 	Equal(t, w1+w2+w3, 31)
 
-	var barrier = barrier{}
-	barrier.bs = [][]byte{
+	var barrier = barrier{
+		bs: make([][]byte, 4),
+	}
+	res := [][]byte{
 		make([]byte, 0),
 		make([]byte, 10),
 		make([]byte, 11),
 		make([]byte, 10),
 	}
+	for i := range res {
+		barrier.bs[i] = res[i]
+	}
 	barrier.ivs = make([]syscall.Iovec, len(barrier.bs))
 	rn, err := readv(r, barrier.bs, barrier.ivs)
 	MustNil(t, err)
 	Equal(t, rn, 31)
-	for i, v := range barrier.bs {
+	for i, v := range res {
 		t.Logf("READ [%d] %s", i, v)
 	}
 }