Get file contents after preprocessor is done
new: make full/path/to/file.i
old: make V=1 file/to/foo.o gives you the full gcc command line from the makefile
then add the -E flag, which instead of a binary, makes it spit out the content of the .c file after the preprocessor is done....
http://www.emacswiki.org/emacs/BuildTags great resource for making tags. Added create-tags function to emacs.