JTAG pins constraints (18.1)

I have a project once had no constraint warning. Then I enabled dynamic reconfiguration ports for Transceiver toolkit.

Since then, every compile show unconstrained warning for:

altera_reserved_ntrst

altera_reserved_tdi

altera_reserved_tms

altera_reserved_tdo

Indeed, I have not specified anywhere about these pins. Similar source code in previous revisions when there is no such warnings.

In a newly created project, I have the same Unconstrained Paths warnings.

I am curious, do I have to constraint JTAG pins?