b.WriteString("abc")
		tw.check(t, "", "")
		b.WriteString("123456789012345")      // long string, non-empty buffer
		tw.check(t, "abc12345", "6789012345") // use Write and then WriteString since the remaining part is still longer than BufSize
	}
	{
		tw := &teststringwriter{}
		b := NewWriterSize(tw, BufSize)
		b.Write([]byte("abc")) // same as above, but use Write instead of WriteString
		tw.check(t, "", "")

// and dereferences the uses of _cgoIndexNN. Taking the address avoids
// making a copy of an array.
//
// This tells _cgoCheckPointer to check the complete contents of the
// slice or array being indexed, but no other part of the memory allocation.
func (p *Package) checkIndex(sb, sbCheck *bytes.Buffer, arg ast.Expr, i int) bool {
	// Strip type conversions.
	x := arg
	for {
		c, ok := x.(*ast.CallExpr)