call graph - question ?

[Virender Kashyap]

HI,
     I had doubt whether in unit-at-time mode call graph is built 
incrementally or is it built only after all the funcitons have been 
parsed (i.e. after cgraph_finalize_compilation unit functions is called). 
In the latter case, where are all the function trees stored then ? 
I presume that cgraph nodes are allotted to respective functions (and 
trees stored there) and only call and return edges are fixed after all funcitons are ready with
  their trees.
Could someone please clarify on this?


Thanks and Regards.
Virender