[MacPorts] #65623: ffmpeg: update to 6.x

[MacPorts]

#65623: ffmpeg: update to 6.x
-------------------------+----------------------
  Reporter:  janngobble  |      Owner:  mascguy
      Type:  update      |     Status:  assigned
  Priority:  Normal      |  Milestone:
 Component:  ports       |    Version:  2.7.2
Resolution:              |   Keywords:
      Port:  ffmpeg      |
-------------------------+----------------------

Comment (by mascguy):

 Replying to [comment:16 mohd-akram]:
 > My hope is that we can update ffmpeg to 6.0 directly, and make broken
 ports use ffmpeg4.

 I don't think that's feasible at this point, as there's far too great a
 chance that we'll cause significant breakage somewhere. Perhaps in the
 future, but I'm certainly not prepared to tackle that at this point.
 Simply too much potential mayhem, without much upside.

 > How would one use ffmpeg6 or (the eventual) ffmpeg4 in a port? Is it a
 matter of updating `configure.cppflags` and `configure.ldflags`?

 Hopefully most can be updated to include the `pkgconfig` path for the
 desired version of `ffmpeg`, via logic similar to the following:

 {{{
 set ffmpeg_ver 6
 configure.pkg_config_path
 ${prefix}/libexec/ffmpeg${ffmpeg_ver}/lib/pkgconfig
 }}}

 We'll also want to segregate `ffmpeg` too, via a new port `ffmpeg4`.
 Otherwise we'll have to deal with reversing the header and lib search
 order, which can be a royal pain.

 Ultimately we'll get there, but it's going to be a big undertaking. (And a
 gradual migration will be far less painful to our users and members.) So
 your patience is appreciated!

-- 
Ticket URL: <https://trac.macports.org/ticket/65623#comment:17>
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