Pointer

    pub const Pointer = struct {
        size: Size,
        attrs: Attributes,
        child: type,

        /// 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,
        };

        /// This data structure is used by the Zig language code generation and
        /// therefore must be kept in sync with the compiler implementation.
        pub const Attributes = struct {
            @"const": bool = false,
            @"volatile": bool = false,
            @"allowzero": bool = false,
            @"addrspace": ?AddressSpace = null,
            @"align": ?usize = null,
        };
    }