[MacPorts] #59834: Boost: update to 1.74.0

[MacPorts]

#59834: Boost: update to 1.74.0
------------------------+--------------------
  Reporter:  michaelld  |      Owner:  (none)
      Type:  update     |     Status:  new
  Priority:  Normal     |  Milestone:
 Component:  ports      |    Version:
Resolution:             |   Keywords:
      Port:  boost      |
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Comment (by reneeotten):

 any progress on this (right now upstream is at version 1.76)? I was
 looking at a build failure for a port and see messages like
 {{{
 /opt/local/include/boost/smart_ptr/detail/sp_counted_base_clang.hpp:29:9:
 error: '_Atomic' is a C11 extension [-Werror,-Wc11-extensions]
 typedef _Atomic( boost::int_least32_t ) atomic_int_least32_t;
 }}}

 that seems to be resolved by
 [https://github.com/boostorg/smart_ptr/issues/78 this commit] and is,
 therefore, likely available for  version after 1.72.

 Is the plan to keep {{{boost}}} following the latest version and add
 {{{boostXYZ}}} to keep older ones around? To maintain the  status quo in
 MacPorts one would need to rename the current {{{boost}}} port to
 {{{boost172}}}, update all ports that depend on it to that new name, and
 then update {{{boost}}} to the latest version - correct? Maintainers can
 then check whether "their" port builds with boost 1.76 and, if so, change
 the dependency. Is there at all a reason to generate ports for
 intermediate versions?

-- 
Ticket URL: <https://trac.macports.org/ticket/59834#comment:11>
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