[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        |
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Comment (by kencu):

 Replying to [comment:10 mouse07410]:
  > Two questions. One - is it possible to somehow "virtualize" the
 environment, so that my experiments would be on a cloned/safe copy rather
 than on the main Macports setup?

 You can set up a separate MacPorts installation for that (tedious as you
 have to build _everything_. Most of us (I think) just keep what we've done
 straight with notes, and undo it if we go down a bad path. Or you can use
 a Virtual Machine (I have many) and clone/hack/test/fix/destroy the VM.

 > Two - it seems to me that Macports GCC should have "-Wa,-q" (or its
 analog) on by default, because otherwise there's no usable assembler
 anyway. Comments?

 That is what the MacPorts' devs have tried to duplicate automatically by
 tweaking the source code to the 'as' component of 'cctools' a few months
 ago. And, frankly, that is what is causing your troubles at the moment, it
 would appear, as you are running into some kind of issue with the tweaked-
 in clang assembler that (so far) nobody else has seen, for whatever
 reason.

-- 
Ticket URL: <https://trac.macports.org/ticket/58442#comment:11>
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