Questa ignores package declaration

I discovered the cause of the problem using the verror command. To look up the meaning of the error codes that are spit out by vlog, you can use the following command:

verror -all

Looking up the 2176 error code seen in my error message, it says:

vlog Message # 2176:
A SystemVerilog source file within a library file specified with -v
contains a package declaration that will not be compiled. Packages are
ignored during library file scanning.

I have been using the -v option to specify the files that contain package definitions, but for some reason, Questa has decided to ignore these. Why? Specifying the directory where they are located using the -y option prevents the above error.