func (pr *pkgReader) tempReader(k pkgbits.RelocKind, idx pkgbits.Index, marker pkgbits.SyncMarker) *reader {
	return &reader{
		Decoder: pr.TempDecoder(k, idx, marker),
		p:       pr,
	}
}

func (pr *pkgReader) retireReader(r *reader) {
	pr.RetireDecoder(&r.Decoder)
}

// @@@ Positions

func (r *reader) pos() token.Pos {
	r.Sync(pkgbits.SyncPos)
	if !r.Bool() {
		return token.NoPos
	}