/etc/ld.so.cache

If I understand correctly, any library directory outside of the standard /lib and /usr/lib locations need to be identified in /etc/ld.so.cache. Is this correct? During my Trinity build and packaging process, I have been inserting /opt/trinity/lib into /etc/ld.so.cache. Do I need to add /opt/trinity/lib/trinity too or are subdirectories of /opt/trinity/lib automatically found by ldconfig? Are there any other library locations from Trinity that belong in /etc/ld.so.cache? When I build Trinity packages, because I am installing to a non standard location, I explicitly declare $LD_LIBRARY_PATH=/opt/trinity/lib in my build environment. I do not declare this variable in during run time. To my understanding, this variable causes the build process to use that location before using library files in the standard locations or /etc/ld.so.cache. Is this correct? Thanks. Darrell