[MacPorts] #54215: gcc7: broken on powerpc

[MacPorts]

#54215: gcc7: broken on powerpc
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  Reporter:  mojca   |      Owner:
      Type:  defect  |     Status:  new
  Priority:  Normal  |  Milestone:
 Component:  ports   |    Version:
Resolution:          |   Keywords:  haspatch
      Port:  gcc7    |
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Comment (by kencu):

 I'm happy to try a build in the morning as well. I saw this but was
 hesitating... this means changing libgcc to libgcc7 as well, correct?

 I haven't yet read much about how libgcc changes in gcc7, but I did see
 there is a libstdc++.6.dylib in it, so I guess it's a "drop in"
 replacement for that file at least (plenty of software on my 10.5 PPC box
 is built with gcc6 or clang-3.8 and links against libstdc++), as does all
 the cxx11 1.1 PortGroup stuff.

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Ticket URL: <https://trac.macports.org/ticket/54215#comment:7>
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