[MacPorts] #56511: gcc49 @4.9.4_2: build fails with Xcode 9 on macOS 10.12

[MacPorts]

#56511: gcc49 @4.9.4_2: build fails with Xcode 9 on macOS 10.12
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  Reporter:  mopihopi  |      Owner:  (none)
      Type:  defect    |     Status:  new
  Priority:  Normal    |  Milestone:
 Component:  ports     |    Version:
Resolution:            |   Keywords:
      Port:  gcc49     |
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Comment (by lancon):

 I am *NOT* a guru, so please be patient and kindly provide answers "for
 dummies". And let me know if I should use another means of communication
 than this.

 I have a similar problem to this one (maybe the same, maybe not). gcc49
 will not build (on OS 10.12.16). I did a "port clean gcc49" and tried
 again (twice). Same failure. I then tried port install gcc5, and also port
 install gcc7... both fail because "The following ports will be rebuilt:
 gcc49 @4.9.4". Apparently, more recent versions need gcc49 ? The
 disturbing thing is I have been able to build gcc49 in the past (more
 specifically, a "port install atlas +gcc49" worked on Nov. 11, 2017 - I
 must have broken something with other installs or cleans after that but
 have no idea what. NB: I have installed only the command line tools of
 Xcode, but that has not been a problem for anything until now (I don't
 know if that is relevant now); in particular it has not stopped the atlas
 install with gcc49 last year.

 The log of the "port install gcc49" is a very long file. Should I really
 paste it here? I imagine one can attach files, but I don't know how.

-- 
Ticket URL: <https://trac.macports.org/ticket/56511#comment:15>
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