Fixed function compilation order

[Cupertino Miranda]

Hello everyone,

I am currently trying to enable GCC to perform compilation without  
having to respect any compilation order, i.e. execute some pass to  
any function at any time (it is not only pass reordering).

As what I have seen from (trunk version of) GCC, it doesn't seem an  
easy task to be achieved and it might traduce in many complications  
later in development.
In that sense I would like to have some opinions and suggestions from  
you all:

  - Imagining I am able to change the function context by updating  
cfun, etc. Will passes (all_passes) execute without
missing/wrong data, i.e. is all shared data between passes accessed/ 
updated thought pointers such as cfun, etc. ?

  - What should I initialise/finalise to be able to perform the  
function context change ?

I would like to have your opinion and tips on how to approach it and  
which problems I might expect to have later.

Thanks in advance,
Cupertino Miranda