[MacPorts] #44129: cmake: fix build against libc++ on Lion

[MacPorts]

#44129: cmake: fix build against libc++ on Lion
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  Reporter:  mojca@…  |      Owner:  michaelld@…
      Type:  defect   |     Status:  new
  Priority:  Normal   |  Milestone:
 Component:  ports    |    Version:
Resolution:           |   Keywords:  lion
      Port:  cmake    |
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Comment (by mojca@…):

 - Yes, I'm on 10.7.
 - No, I don't have `+replacement_libcxx` activated. Yes, `libcxx` is a
 placeholder package only (no contents other than the `README`).
 - As I already explained:
   - `clang++` fails (Apple LLVM version 4.2 (clang-425.0.28) (based on
 LLVM 3.2svn))
   - `clang++-mp-3.3` fails (I just installed and tested that one; I'm not
 eager to install < 3.3.)
   - `clang++-mp-3.4` and `clang++-mp-3.5` work (I assume higher versions
 do as well.)
 I would assume that clang-3.4 fixed the problem even for the broken
 `libc++` then ;)

 If it was easier (=faster) to compile clang, I would happily do the
 bisection to find the relevant commit, but it's not relevant enough to
 spend days compiling.

 It might be interesting to test on 10.6 and to test whether the old Xcode
 on 10.8 produces the error, but large amount of work would not justify the
 benefit of knowing the output.

-- 
Ticket URL: <https://trac.macports.org/ticket/44129#comment:26>
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