[MacPorts] #71770: mlt @7.24.0_0+qt6 build failure

[MacPorts]

#71770: mlt @7.24.0_0+qt6 build failure
------------------------+----------------------
  Reporter:  amadeus24  |      Owner:  ddennedy
      Type:  defect     |     Status:  assigned
  Priority:  Normal     |  Milestone:
 Component:  ports      |    Version:  2.10.5
Resolution:             |   Keywords:
      Port:  mlt        |
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Comment (by RJVB):

 Replying to [comment:2 ddennedy]:
 > This is compatibility problem building with FFmpeg. There is code here
 in MLT to handle different versions, and the configure step for MLT
 appeared to have found an older version of FFmpeg (<=5) that has
 `avfilter_pad_count`, but linking used the newer version (6) with the
 symbol changed to `avfilter_filter_pad_count`.

 FWIW, I too have noticed that it can be tricky to have FFmpeg 4.x and
 FFmpeg 6.x installed in the same prefix, with more or less the same
 confusion during the configure and during the build/link steps.

 This would not happen if MacPorts supported "-dev" ports like the ones
 most Linux distribs have. Without that, `port:mlt` should declare a build
 conflict on the full port:ffmpeg rather than on just port:ffmpeg-dev .

 But at least `conflicts_build ffmpeg` will address this issue.

-- 
Ticket URL: <https://trac.macports.org/ticket/71770#comment:5>
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