The dynamic linker can clearly tell you where it looks for files and in which order, and where it finds them if it does.

You can also very easily harden this if you somehow don't want to capture libraries from outside certain paths.

You can even build the compiler in such a way that every binary it produces has a built-in RPATH if you want to force certain locations.

That is what I'm doing so I can get distributed builds working. It sucks and has taken me days of work.