[MacPorts] #54773: port:libgcc/port:gcc7: proposed modifications, efficiency + libc++ support

[MacPorts]

#54773: port:libgcc/port:gcc7: proposed modifications, efficiency + libc++ support
--------------------------+----------------------
  Reporter:  RJVB         |      Owner:
      Type:  enhancement  |     Status:  new
  Priority:  Normal       |  Milestone:
 Component:  ports        |    Version:
Resolution:               |   Keywords:  haspatch
      Port:  gcc7 libgcc  |
--------------------------+----------------------

Comment (by RJVB):

 Is it still possible to target 10.5 or 10.4 from, say, 10.9? I presume
 you'd need the corresponding SDKs, can you just copy them over?

 I'm going to prepare updated patches. They'll look even more complex
 because I've been moving more things around in an effort to improve
 maintainability and upgrading.

 I'll start giving port:gcc8 the same makeover but I can't promise I'll be
 doing a lot of testing with a beta compiler. I have no idea what new
 amazing features gcc8 introduces but unless there's something we never
 knew we wanted in there I would expect the gcc7 audience to be larger :)

--
Ticket URL: <https://trac.macports.org/ticket/54773#comment:17>
MacPorts <https://www.macports.org/>
Ports system for macOS