I'm trying to obtain a list of global variables declared in a large Ada project. gnatcheck has a rule for that: Global_Variables, but that rule is not exhaustive:

"Flag any variable declaration that appears immediately within the specification of a library package or library generic package. Variable declarations in nested packages and inside package instantiations are not flagged"

I'd like to be able to obtain the list of variables declared in package instantiations as well. I would try to implement my own gnatcheck custom rule, but cannot seem to find where the rules are implemented. This doc says it's supposed to be in share/lkql, but there is no such directory in my GNAT Studio installations (I've looked at GNAT Pro 19.2, GNAT Pro 22.1 and Gnat Community 2021). Windows cannot find any .lkql file.

Is it possible to make such a rule? If so, how/where? Are there alternatives to gnatcheck to obtain the list of global variables?