gistfile1.txt

# grep use_pkgng /usr/local/etc/portmaster.rc
use_pkgng=yes

# portmaster math/gmp

<< SNIP >>

===>  Installing for gmp-5.0.4
===>   Generating temporary packing list
===>  Checking if math/gmp already installed
===>   An older version of math/gmp is already installed (gmp-5.0.3)
      You may wish to ``make deinstall'' and install this port again
      by ``make reinstall'' to upgrade it properly.
      If you really wish to overwrite the old port of math/gmp
      without deleting it first, set the variable "FORCE_PKG_REGISTER"
      in your environment or the "make install" command line.
*** Error code 1

Stop in /usr/ports/math/gmp.
*** Error code 1

Stop in /usr/ports/math/gmp.

===>>> Installation of gmp-5.0.4 (math/gmp) failed
===>>> Aborting update

Terminated

===>>> You can restart from the point of failure with this command line:
       portmaster <flags> math/gmp