pub const BuiltinCall = struct {
    // Note: Flags *must* come first so that unusedResultExpr
    // can find it when it goes to modify them.
    flags: Flags,
    modifier: Ref,
    callee: Ref,
    args: Ref,

    pub const Flags = packed struct {
        is_nosuspend: bool,
        ensure_result_used: bool,
        _: u30 = undefined,

        comptime {
            if (@sizeOf(Flags) != 4 or @bitSizeOf(Flags) != 32)
                @compileError("Layout of BuiltinCall.Flags needs to be updated!");
        }
    };
}