EFI_ACPI_6_0_NFIT_GUID_RAM_DISK_SUPPORTING_VIRTUAL_CD_REGION_VOLATILE

Undocumented in source but is binding to C. You might be able to learn more by searching the web for its name.
extern (C)
enum EFI_ACPI_6_0_NFIT_GUID_RAM_DISK_SUPPORTING_VIRTUAL_CD_REGION_VOLATILE = GUID(0x3D5ABD30, 0x4175, 0x87CE, 0x6D, 0x64, 0xD2, 0xAD, 0xE5, 0x23, 0xC4, 0xBB);

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