This is extremely likely - as Graham has already mentioned; look up "common tail merging" etc in the Manual.


Playing tricks on a 'C' compiler is a very bad idea indeed!!
The compiler knows what it's doing when it generates its code - if you mess with it, you are highly likely to break something, and give yourself some very bizarre & obscure bugs that will be extremely difficult to debug.
I'm afraid the fact that you need to ask the question does rather suggest that you are not sufficiently familiar with the internal workings of the compiler to safely do this sort of thing - let alone debug the problems when it goes wrong!

If you really do need to do this, do it in assembler - where you have complete control, and a free rein to do whatever you like.