func (p *Profile) Write(w io.Writer) error {
	zw := gzip.NewWriter(w)
	defer zw.Close()
	_, err := zw.Write(serialize(p))
	return err
}

// WriteUncompressed writes the profile as a marshaled protobuf.
func (p *Profile) WriteUncompressed(w io.Writer) error {
	_, err := w.Write(serialize(p))
	return err
}

// CheckValid tests whether the profile is valid. Checks include, but are
// not limited to:

type profileCopier []byte

func makeProfileCopier(src *profile.Profile) profileCopier {
	// Pre-serialize the profile. We will deserialize every time a fresh copy is needed.
	var buf bytes.Buffer
	src.WriteUncompressed(&buf)
	return profileCopier(buf.Bytes())
}

// newCopy returns a new copy of the profile.
func (c profileCopier) newCopy() *profile.Profile {
	p, err := profile.ParseUncompressed([]byte(c))