Makefile issues

[Stanya]

I'm working on a project that has to do with the make command in UNIX to build 
projects. There are makefiles involved - in fact, a makefile tree where there 
subdirectories with their own makefiles which are called upon by the main 
makefile (recursive makes). These deal with C/C++ sources for the most part, 
but not limited to.

What I need to do is figure out which files in the project are used for which 
applications - each build can consist of several applications. I'll be writing 
a Perl script (if this is possible) that basically spits out info about the 
files used for each application in the whole build - some files might be shared 
by more than on application in a single build.

Is there any possible way from reading the main makefile (root directory of the 
project) and extracting this information? I don't necessarily use GNU make to 
'make' the makefiles, but that's not the problem. I've found a way to extract 
all the directories and files used by a makefile tree, but I still don't know 
if it's possible to organize this by applications.

Thanx for any help I can get!!!