PVS-Studio warning V629 for SeqAn

template <typename TValue, unsigned SIZE>
struct Tuple<TValue, SIZE, BitPacked<> >
{
  typedef typename
    BitVector_<SIZE * BitsPerValue<TValue>::VALUE>::Type
    TBitVector;

  static const __uint64 BIT_MASK =
    (1 << BitsPerValue<TValue>::VALUE) - 1;
  ....
}

This suspicious code was found in SeqAn project by PVS-Studio static code analyzer.
Warning message is:
V629 Consider inspecting the '1 << BitsPerValue < TValue >::VALUE' expression. Bit shifting of the 32-bit value with a subsequent expansion to the 64-bit type. tuple_bit_compressed.h 88

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