[MacPorts] #52328: opencv 3.1.0 fails build on macOS Sierra

[MacPorts]

#52328: opencv 3.1.0 fails build on macOS Sierra
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  Reporter:  jefrey_c@…  |      Owner:  stromnov@…
      Type:  defect      |     Status:  new
  Priority:  Normal      |  Milestone:
 Component:  ports       |    Version:  2.3.4
Resolution:              |   Keywords:  sierra
      Port:  opencv      |
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Comment (by milutz@…):

 Relevant links:

  - Link to opencv bug and fix:
 https://github.com/opencv/opencv/issues/6913 (also offers side-effect-
 laden workaround of:  {{{ cmake -DBUILD_opencv_videoio=OFF . }}} for
 current released source)
  - Link to homebrew workaround (building off of head):
 https://github.com/Homebrew/homebrew-science/issues/4104

 I don't know how to take advantage of the above because I don't know how
 to force the port to have build options outside of what is defined in the
 variants (which {{{videoio}}} isn't) and/or force it to build off of the
 repo {{{HEAD}}} (as the homebrew people can)

-- 
Ticket URL: <https://trac.macports.org/ticket/52328#comment:10>
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