[Lazarus] How to find out why a unit is used in a project?

[Bo Berglund]

I am porting a Delphi application to Linux and as a stop I am first
doing it from Delphi to Lazarus/Fpc on Windows.

Now when I try to compile it throws an error inside a unit I did not
even know it used. And to further complicate the issue I cannot find a
reference to the unit in question when doing a search in the project
dir inside all pas files. This unit is not mentioned anywhere and
still causes a compile error due to a missing reference.

I tried Lazarus Find In Files and set it to search "all files in
project" and also search the project directory, but it comes up
empty-handed...

So now I wonder:
Is there a Lazarus tool to trace why the unit is referenced in the
first place? Is there such things as "chain of uses"?

The application I am porting is a client communications app that talks
to a service over TCP/IP.
That service app uses the unit that pos up as erroneous now, but it
should not be used by the client comm app at all.
So I need to find out why it does.

-- 
Bo Berglund
Developer in Sweden