A question for the parse tree

[cgllinux@sjtu.edu.cn]

hi all,
I am the newbie for gcc, And now doing the research for static buffer overflow\'s detection, So I want to get the enough syntax infomation for doing the analysis.But When I use the option -fdump-translation-unit-all to dump the tree, it seems that the tree lost
some infomations(because two differnt tests result in the same dump file),  So my question is:
 1: Any other option for dumping the original parse tree or the whole infomation?
 2; if the whole tree infomation can not be gotten, any other approach for static detection?
pls forgive my ingnorance
Thanks in advance

  Danny