How to make consistent dll binaries across VS versions?

struct IExportedMethods {
    virtual long __stdcall AMethod(void)=0;
  };
  // with the win32 macros:
  interface IExportedMethods {
    STDMETHOD_(long,AMethod)(THIS)PURE;
  };

class CMyObject: public IExportedMethods { ...

extern "C" __declspec(dllexport) IExportedClass* WINAPI CreateMyExportedObject(){
    return new CMyObject;
  }

interface IExportedMethods {
    STDMETHOD_(void) Release(THIS) PURE; };
  class CMyObject : public IExportedMethods {
    STDMETHODIMP_(void) Release(){
      delete this;
    }
  };

#pragma pack(push,4)
typedef myStruct {
  int a;
  char b;
  float c;
}myStruct;
#pragma pack(pop)