Aubit 4GL source compiler 4glc is generally invoked using the 4glpc wrapper. It can be involked directly :

aubit 4glc <filename>.4gl

For historic reasons, the 4glc compiler can also compile most modules to an executable. In order to do this the 4glc compiler uses the normal C compiler and passes unknown options on to it e.g.:
aubit 4glc file.4gl -c -o file.o

aubit 4glc -shared file.4gl -o file.4ge

aubit 4glc -static -echo file.4gl -o file.4ge

aubit 4glc -debug file.4gl -o file.debug

aubit 4glc -map -echo file.4gl

compiles to an object file rather than a linked executable

It is now best practice, unless there is a very good reason otherwise, to not call 4glc directly as all, and to invoke it via the 4glpc wrapper instead.