PVS-Studio warning V556 for UnrealEngine4

namespace EOnlineSharingReadCategory
{
  enum Type
  {
    None          = 0x00,
    Posts         = 0x01,
    Friends       = 0x02,
    Mailbox       = 0x04,
    OnlineStatus  = 0x08,
    ProfileInfo   = 0x10,
    LocationInfo  = 0x20,
    Default       = ProfileInfo|LocationInfo,
  };
}

namespace EOnlineSharingPublishingCategory
{
  enum Type {
    None          = 0x00,
    Posts         = 0x01,
    Friends       = 0x02,
    AccountAdmin  = 0x04,
    Events        = 0x08,
    Default       = None,
  };

  inline const TCHAR* ToString(
    EOnlineSharingReadCategory::Type CategoryType)
  {
    switch (CategoryType)
    {
    case None:
    {
      return TEXT("Category undefined");
    }
    case Posts:
    {
      return TEXT("Posts");
    }
    case Friends:
    {
      return TEXT("Friends");
    }
    case AccountAdmin:
    {
      return TEXT("Account Admin");
    }
    ....
  }
}

This suspicious code was found in UnrealEngine4 project by PVS-Studio static code analyzer.
Warning message is:
V556 The values of different enum types are compared: switch(ENUM_TYPE_A) { case ENUM_TYPE_B: ... }. onlinesubsystemtypes.h 1154

PVS-Studio is a static analyzer for detecting bugs in the source code of applications written in C, C++, C++11, C++/CX. Site: http://www.viva64.com/en/pvs-studio/