pub const CC = enum(u8) {
    normal = 0x1,
    program = 0x2,
    nocall = 0x3,

    pass_by_reference = 0x4,
    pass_by_value = 0x5,

    GNU_renesas_sh = 0x40,
    GNU_borland_fastcall_i386 = 0x41,

    BORLAND_safecall = 0xb0,
    BORLAND_stdcall = 0xb1,
    BORLAND_pascal = 0xb2,
    BORLAND_msfastcall = 0xb3,
    BORLAND_msreturn = 0xb4,
    BORLAND_thiscall = 0xb5,
    BORLAND_fastcall = 0xb6,

    LLVM_vectorcall = 0xc0,
    LLVM_Win64 = 0xc1,
    LLVM_X86_64SysV = 0xc2,
    LLVM_AAPCS = 0xc3,
    LLVM_AAPCS_VFP = 0xc4,
    LLVM_IntelOclBicc = 0xc5,
    LLVM_SpirFunction = 0xc6,
    LLVM_OpenCLKernel = 0xc7,
    LLVM_Swift = 0xc8,
    LLVM_PreserveMost = 0xc9,
    LLVM_PreserveAll = 0xca,
    LLVM_X86RegCall = 0xcb,
    LLVM_M68kRTD = 0xcc,
    LLVM_PreserveNone = 0xcd,
    LLVM_RISCVVectorCall = 0xce,
    LLVM_SwiftTail = 0xcf,

    pub const lo_user = 0x40;
    pub const hi_user = 0xff;
}