Holy cow!
That has to be the most horrific hack I have ever, ever seen
Nicely done
Not only is it ludicrously compiler dependent, it's most likely operating system dependent and hardware dependent. Could easily be day-of-the-week dependent, for that matter.
I sure hope it's a silly experiment and not an excuse to avoid DLLs - if your code looks like that, then it really is time to learn how to use DLLs.
It's not really quite how DLLs work. You can have DLL functions dynamically bound in your own code using function pointers (this is how things like plugins work). But you need the OS to load the DLL into the right place, in the right way, and then you need to use the OS's function in order to extract the function pointer you need.
You can also have them dynamically bound by the OS based on instructions inserted by the compiler (this is how things like user32.dll work), so that the functions themselves will look statically bound within your own code.