sig
  type t =
      Zext
    | Sext
    | Noreturn
    | Inreg
    | Structret
    | Nounwind
    | Noalias
    | Byval
    | Nest
    | Readnone
    | Readonly
    | Noinline
    | Alwaysinline
    | Optsize
    | Ssp
    | Sspreq
    | Alignment of int
    | Nocapture
    | Noredzone
    | Noimplicitfloat
    | Naked
    | Inlinehint
    | Stackalignment of int
    | ReturnsTwice
    | UWTable
    | NonLazyBind
end