How to check if two events are pointing to the same procedure in Delphi?

Say I have a Button1.OnClick event linked to Button1Click procedure. I also have Button2.OnClick linked to some other procedure. How do I check in runtime if both events are linked to different procedures or the same procedure?

I tried to test if:

• Button1.OnClick = Button2.OnClick, but that gave me an error (Not enough actual parameters)
• @(Button1.OnClick) = @(Button2.OnClick), error again (Not enough actual parameters)

How do I test it properly?