pub const Pointer = struct {
    size: Size,
    is_const: bool,
    is_volatile: bool,
    /// TODO make this u16 instead of comptime_int
    alignment: comptime_int,
    address_space: AddressSpace,
    child: type,
    is_allowzero: bool,

    /// The type of the sentinel is the element type of the pointer, which is
    /// the value of the `child` field in this struct. However there is no way
    /// to refer to that type here, so we use `*const anyopaque`.
    /// See also: `sentinel`
    sentinel_ptr: ?*const anyopaque,

    /// Loads the pointer type's sentinel value from `sentinel_ptr`.
    /// Returns `null` if the pointer type has no sentinel.
    pub inline fn sentinel(comptime ptr: Pointer) ?ptr.child {
        const sp: *const ptr.child = @ptrCast(@alignCast(ptr.sentinel_ptr orelse return null));
        return sp.*;
    }

    /// This data structure is used by the Zig language code generation and
    /// therefore must be kept in sync with the compiler implementation.
    pub const Size = enum(u2) {
        one,
        many,
        slice,
        c,
    };
}