[MacPorts] #39975: root: Add --enable-cxx11 when using libc++

[MacPorts]

#39975: root: Add --enable-cxx11 when using libc++
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  Reporter:  jfcaron@…    |      Owner:  jeremyhu@…
      Type:  enhancement  |     Status:  assigned
  Priority:  Normal       |  Milestone:
 Component:  ports        |    Version:  2.2.0
Resolution:               |   Keywords:
      Port:  root         |
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Comment (by jeremyhu@…):

 Replying to [comment:20 jfcaron@…]:
 > Replying to [comment:19 jeremyhu@…]:
 > > Yeah, that's because it won't be enabled on your configuration.  You'd
 need to install base trunk, choose libc++ as your C++ runtime, and
 reinstall all of your ports.
 > >
 > > I suggest you set this in /opt/local/etc/macports/macports.conf :
 > > {{{
 > > buildfromsource         always
 > > delete_la_files    yes
 > > cxx_stdlib libc++
 > > }}}
 > >
 > > delete_la_files is there because this is a good opportunity for you to
 do that as well (it would require a full reinstall just like switching the
 C++ runtime)
 > >
 > > Note that Lion's libc++ is a bit older and you may run into issues
 that have been fixed in Mountain Lion and Mavericks that weren't pulled
 back into Lion software updates.
 >
 > Ah, that's a bit more drastic than I would like just to test a new
 portfile configuration.  I thought I just needed to have the port libcxx
 installed.  How likely is installing base trunk & switching C++ runtimes
 to break a bunch of stuff?  I'm willing to try it, but I don't want to be
 unable to do real work come Monday morning because of broken ports...

 I'm doing that on all but one of my Mountain Lion machines.

 I was doing that on my Lion machine when I still had one.

 I didn't encounter any issues which I didn't also encounter with
 Mavericks, and most of those are fixed or getting fixed.

-- 
Ticket URL: <https://trac.macports.org/ticket/39975#comment:21>
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