Is there an equivalent of -I (capital I) for object files in g++?

I have several object files coming from different directories (they are stored near the corresponding source that generated them). Is there a way that given this directory structure

Root

main.o

Root/Some_long_path

object_1.o
object_2.o

I could run a command like this

g++ -Wall main.o -ISome_long_path object_1.o object_2.o -o app

So that I don't have to put the full path in front of every object file. What would go instead of the -I command?

I am using gcc version 4.8.3 (from Cygwin installation).