[MacPorts] #59835: cmake: strange libc++ "if" condition

[MacPorts]

#59835: cmake: strange libc++ "if" condition
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  Reporter:  michaelld  |      Owner:  michaelld
      Type:  defect     |     Status:  closed
  Priority:  Normal     |  Milestone:
 Component:  ports      |    Version:
Resolution:  fixed      |   Keywords:
      Port:  cmake      |
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Comment (by kencu):

 Replying to [comment:13 RJVB]:

 > What if you build libc++ like it is done on Linux, that is against
 libstdc++? I cannot recall whether I did that using GCC instead of Clang,
 but I think it should be possible. Then, apply my libc++ patch for GCC
 (currently for GCC 7) and you can use `g++-mp-X -stdlib=libc++`. If I had
 been more dedicated to this little project the patch would probably have
 made it into GCC already...
 > I assume that dependent code being built against libc++ doesn't see what
 ABI library libc++ uses behind the scenes (libc++ can work with at least
 3).

 I have in fact had libc++ running on PPC for a year or so, myself, and
 clang-5.0. Just waiting to see if/when it might be a good idea to unleash
 it on MacPorts. There are a few residual assembler hiccups that I think
 your gcc/libc++ enhancements might well fix.

 {{{
 $ port -v installed libcxx
 The following ports are currently installed:
   libcxx @5.0.1_4+emulated_tls-universal platform='darwin 9' archs='ppc'
 date='2019-01-15T21:53:44-0800'
 }}}

-- 
Ticket URL: <https://trac.macports.org/ticket/59835#comment:15>
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