This is about compiling and running multilib between different architectures ( 32 / 64 bit ):
If You want to build for different libs / kernel version just change the include/library paths in Your build scripts
Parameters for gcc like -i -L -I most likely are configured in makefiles. Also read man for gcc and make.
You can have many different versions of same libs/sources installed in the system, same goes for different kernels and kernel sources.
Hope it helps.