how keep particular broken port from trying to reinstall?

[Ryan Schmidt]

> On Jan 17, 2016, at 4:52 PM, Murray Eisenberg <murrayeisenberg at gmail.com> wrote:
> 
> On Jan 17, 2016, at 12:26 PM, Rainer Müller <raimue at macports.org> wrote:
>> 
>> On 2016-01-17 18:13, Murray Eisenberg wrote:
>>> 1. Each time I upgrade any ports, automatically MacPorts notices that
>>> the port for qt4-mac is broken and attempts to build it again.
>>> 
>>> Is there any way to do upgrades of other points without the
>>> time-consuming (always failing) attempt to rebuild qt4-mac?
>> 
>> sudo port [upgrade|install] --no-rev-upgrade
>> 
>>> 2. I’d try to uninstall qt4-mac and re-install the older version that, I
>>> believe, was unbroken.  But there are a whole bunch of other ports that
>>> depend on it. How may I get around uninstalling those dependent ports
>>> and reinstalling them later?  (I believe I need to use a “-f” parameter
>>> but otherwise am uncertain how to do this.)
>> 
>> You probably still have the older qt4-mac installed, so you can simply
>> reactivate it:
>> 
>> https://trac.macports.org/wiki/howto/InstallingOlderPort#reactivate
> 
> The older qt4-mac (qt4-mac @4.8.7_2) is still active. It just won’t upgrade to current version.

Why not?