[MacPorts] #58442: gcc9 (and other gccN) fails to install on Mojave, Xcode-10.2.1

[MacPorts]

#58442: gcc9 (and other gccN) fails to install on Mojave, Xcode-10.2.1
-------------------------+--------------------
  Reporter:  mouse07410  |      Owner:  (none)
      Type:  defect      |     Status:  new
  Priority:  Normal      |  Milestone:
 Component:  ports       |    Version:
Resolution:              |   Keywords:
      Port:  gcc9        |
-------------------------+--------------------

Comment (by mouse07410):

 > Here's a thought. What variant of {{{cctools}}} do you have installed?

 Darn!! *&^&%! @#$%! @#*&!  Great thought, and very correct. :-(

 > Did you force the installation of a different {{{cctools}}} variant? If
 so, that is likely your trouble.

 Well, the default was/is {{{[+llvm70]}}}:
 {{{
 $ port info cctools
 cctools @921_1 (devel)
 Variants:             llvm39, llvm40, llvm50, llvm60, [+]llvm70, llvm80,
 llvmdev, universal, xcode

 Description:          A set of essential tools to support development on
 Mac OS X and Darwin. Conceptually
                       similar similar to binutils on other platforms.
 Homepage:             https://opensource.apple.com/source/cctools/

 Build Dependencies:   libunwind-headers
 Library Dependencies: llvm-7.0
 Platforms:            darwin
 License:              (APSL-2 or GPL-2+)
 Maintainers:          Email: jeremyhu at macports.org, GitHub: jeremyhu
                       Policy: openmaintainer
 }}}

 After the above failure, I forced it to {{{+llvm80}}} (still causing
 failures). And now, forcing it to {{{+xcode}}} (which is *not* the
 default, as far as I can see), seemed to improve a lot - at least I don't
 seem to need {{{-Wa,-q}}}, at least in general (would have to check with
 Crypto++).

-- 
Ticket URL: <https://trac.macports.org/ticket/58442#comment:14>
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