message: Compress Blosc: Fix MSVC Build
  Generalize packed data attributes.
diff: #include "adios2/core/Operator.h"
  +#if defined(_MSC_VER)
  +#define ADIOS2_CLASS_PACKED(name) __pragma(pack(push, 1)) class name
  +#define ADIOS2_CLASS_PACKED_SUFFIX __pragma(pack(pop))
  +#else
  +#define ADIOS2_CLASS_PACKED(name) class __attribute__((packed)) name
  +#define ADIOS2_CLASS_PACKED_SUFFIX
  +#endif
  +
  namespace adios2
  {
  namespace core
  @@ -77,7 +85,7 @@ private:
  void *dataOut, const size_t sizeOut,
  Params &info) const;
  - class __attribute__((packed)) DataHeader
  + ADIOS2_CLASS_PACKED(DataHeader)
  {
  /** compatible to the first 4 byte of blosc header
  *
  @@ -106,7 +114,8 @@ private:
  uint32_t GetNumChunks() const { return numberOfChunks; }
  bool IsChunked() const { return format == 0; }
  - };
  + }
  + ADIOS2_CLASS_PACKED_SUFFIX;
  static const std::map<std::string, uint32_t> m_Shuffles;
  static const std::set<std::string> m_Compressors;
  @@ -116,4 +125,7 @@ private:
  } // end namespace core
  } // end namespace adios2
  +#undef ADIOS2_CLASS_PACKED
  +#undef ADIOS2_CLASS_PACKED_SUFFIX
  +
  #endif /* ADIOS2_OPERATOR_COMPRESS_COMPRESSBLOSC_H_ */
  