[MacPorts] #56294: boost: update to 1.69.0

[MacPorts]

#56294: boost: update to 1.69.0
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  Reporter:  michaelld  |      Owner:  ryandesign
      Type:  update     |     Status:  assigned
  Priority:  Normal     |  Milestone:
 Component:  ports      |    Version:
Resolution:             |   Keywords:  haspatch maintainer
      Port:  boost      |
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Comment (by michaelld):

 I haven't had or taken the time to work over the boost dependencies to
 make sure that 90%+ of them work. There are some 250 ports that depend on
 Boost, so doing this check isn't trivial. It's also a challenge to know
 which ports don't build with the current Boost and ignore them if they
 still don't build.

 MacPorts needs a better way to do testing / verification of such ports
 that are depended on so heavily; doing it manually as we currently do
 means that someone has to find and take the time to do all of this
 checking -- and, then fixing and/or issuing tickets for those that aren't
 easily fixable. Maybe crowdsourcing this checking is the way to go?

 If you need something right now, use the patch attached to this ticket to
 update to Boost 1.68.0. There is no patch for 1.69.0 because the Boost
 folks changed the default API naming scheme to include the "ARCH" type &
 that wreaks havoc on CMake-based builds on macOS / OSX (but, not in
 general). Again, I have't had or taken the time to figure out the change
 to revert the "ARCH" to get back to what MacPorts desires (and what works
 for CMake).

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Ticket URL: <https://trac.macports.org/ticket/56294#comment:16>
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