These options specify directories to search for files, libraries, and other parts of the compiler:

-Idir

Add the directory dir to the list of directories to be searched for files when processing the pragmat include. Multiple -I options can be used, and the directories specified are scanned in left-to-right order, as with gcc. The directory will also be added to the list of directories to be searched for module interface-definitions Module activation.

-Ldir

Add the directory dir to the list of directories to be searched for module interface-definitions Module activation. Multiple -L options can be used, and the directories specified are scanned in left-to-right order, as with gcc. The directory will also be added to the list of library search directories, as with gcc.