[MacPorts] #33259: cmake portgroup: out of source build option, possibly by default

[MacPorts]

#33259: cmake portgroup: out of source build option, possibly by default
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  Reporter:  ryandesign@…  |      Owner:  macports-tickets@…
      Type:  enhancement   |     Status:  new
  Priority:  Normal        |  Milestone:
 Component:  ports         |    Version:
Resolution:                |   Keywords:
      Port:                |
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Comment (by michaelld@…):

 Replying to [comment:15 mojca@…]:
 > What's the best way to introduce a new global variable (if we can agree
 on that and its name)? Does one need to upgrade MacPorts for the change to
 take effect? (If we would need an upgrade, it might be better to first
 introduce in the CMake PortGroup nevertheless and then move it to a global
 place once a new release comes to the horizon.)

 Good question. I'm not sure of the answer. Since the change is going into
 the PortGroup, I think it'll become part of user's install when they
 "selfupdate" or "sync", which means we can start using the variable
 immediately in Portfiles. I might be wrong though. Hopefully someone else
 knows for sure.

-- 
Ticket URL: <https://trac.macports.org/ticket/33259#comment:16>
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