[MacPorts] #58260: gcc{6, 7, 8, 9} : Build failures due to "Atomic" error with macOS 10.4.4 and Xcode 10.2

[MacPorts]

#58260: gcc{6,7,8,9} : Build failures due to "Atomic" error with macOS 10.4.4 and
Xcode 10.2
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  Reporter:  physicsbeany                        |      Owner:  (none)
      Type:  defect                              |     Status:  new
  Priority:  Normal                              |  Milestone:
 Component:  ports                               |    Version:  2.5.4
Resolution:                                      |   Keywords:  mojave
      Port:  gcc9 gcc8 gcc7 gcc6 libgcc-devel    |
  libgcc8 libgcc7 libgcc6                        |
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Comment (by cjones051073):

 Regarding gcc9, please note this is not a production compiler, but a build
 of one of the gcc snapshot development versions. No other port in MacPorts
 should depend on it, so I suggest you just uninstall it for now, and use
 gcc8 instead, which should install for you as you will use the pre-built
 binary tarball.

 I am sorry to hear about the accessibility issues you had with the
 website. I guess no one has ever tried using it with accessibility in
 mind. Please bear in mind the site is community maintained, so unless
 someone steps up with specific suggestions, or audits it specifically for
 accessibility, its perhaps not surprising it isn't as easy to use as it
 should be. What would help, is if you have specific suggestions of things
 to change, as I guess few have screen readers so would be able to know
 what the issues are.

 "Atomic Error" is just a para-phrasing of the compiler error that is
 generated, that refers to a missing type, that if I have understood things
 correct is due to an issue with incorrectly including/using C/C++ types in
 the wrong context.

-- 
Ticket URL: <https://trac.macports.org/ticket/58260#comment:20>
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