[MacPorts] #38406: boost: disable no_single by default

[MacPorts]

#38406: boost: disable no_single by default
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  Reporter:  aronnax@…  |      Owner:  adfernandes@…
      Type:  request    |     Status:  assigned
  Priority:  Normal     |  Milestone:
 Component:  ports      |    Version:  2.1.3
Resolution:             |   Keywords:
      Port:  boost      |
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Changes (by adfernandes@…):

 * owner:  macports-tickets@… => adfernandes@…
 * status:  new => assigned


Comment:

 Hello - I'm reasonably familiar with condor, and I guess that I'd want to
 ask if you're sure that the mac version '''requires''' the single-threaded
 version? (As in "it really needs it because of the wonky things that
 condor does to the thread and run states of a process", not (and I'm sorry
 if this sounds snotty) "it requires single-threaded because that's how the
 condor packagers assumed would be simplest".

 The Mac ABI and libraries are different from Linux because almost
 everything is multithreaded by default; it's actually rather tricky to
 build "from the low-level guts only single-threaded code". In fact, if you
 search for `_REENTRANT` in the system headers, you'll find that it is only
 used in
 * the `c++/4.2.1/bits` runtime (in the `gthr-*` threading includes)
 * the ldap header
 * libexslt
 * libxml
 * libxslt
 * net-snmp
 * the system php includes
 * and the gamma and log-gamma functions (and variants) in `math.h`.
 All of these are actually hold-overs from Linux or gnu systems, or where
 they optimize to have one control structure rather than a shared control
 structure.

 To actually answer your question/request :-) what ends up being shorter
 compile times for condor ends up being long for others. In particular,
 choosing a python version requires extra compilation.

 But really, for 99% of people, I think that the pre-compiled Port will be
 used. So... I can remove the `no_static` and `no_single` variants if other
 people will weigh in with their opinions. (I added these default variants
 before the MacPorts build system went live, so they may be obsolete
 now...)

 Opinions, anyone?

-- 
Ticket URL: <https://trac.macports.org/ticket/38406#comment:1>
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