[fpc-pascal] Recursion optimization by compiler

[Bihar Anwar]

After my previous post, "TreeView and Nonrecursion", I'd tried to ask the same 
topics in stackoverflow.com 
(http://stackoverflow.com/questions/3630047/treeview-control-and-nonrecursion) 
and I got something new.

It is possible to recurse without using up the stack space.  Optimizing  
compilers are able to accomplish certain types of recursion into  efficient 
non-recursive loops, but the code has to be written into a tail recursion form.

Is there such a recursion optimization in FPC? If it is not enabled by default, 
how to enable it?