[MacPorts] #60148: mkvtoolnix: Update to version 43

[MacPorts]

#60148: mkvtoolnix: Update to version 43
-------------------------+------------------------
  Reporter:  mf2k        |      Owner:  ryandesign
      Type:  update      |     Status:  assigned
  Priority:  Normal      |  Milestone:
 Component:  ports       |    Version:
Resolution:              |   Keywords:
      Port:  mkvtoolnix  |
-------------------------+------------------------

Comment (by kencu):

 I have not yet worked out what the full deal is here, but the
 configuration fails during c++17 feature tests. In particular, it failed
 looking for a {{{value}}} operator. Digging in on that a bit, that is
 marked as being unavailable on macOS prior to 10.14 in the {{{optional}}}
 include file, and that is driven by this:
 {{{
 /opt/local/libexec/llvm-9.0/include/c++/v1/__config
 }}}
 down around line 1172, that macOS availability functionality can be
 disabled like this:
 {{{
 #  ifdef __APPLE__
 //#    define _LIBCPP_USE_AVAILABILITY_APPLE
 #  endif
 }}}
 and that turns off the entire libcpp availability macro infrastructure.

 I assume this infrastructure is looking at the libc++ versions that are
 included by default with various versions of macOS, and using availability
 macros based on that default libc++.

 10.6.8 with MacPort's libcxx has a libc++ that corresponds to clang-5.0 at
 present (it could be clang-7.0's pretty easily) -- I'm not 100% sure where
 10.13 and 10.14 fall into that mixture. Disabling those availability tests
 might cause troubles on systems that have default libc++.dylibs installed
 perhaps.

 The mkvtoolnix applications then build through it seems, but the install
 phase fails with some kind of an error generating the docs I think:
 {{{
 runtime error: file /opt/local/share/xsl/docbook-xsl-nons/lib/lib.xsl line
 57 element call-template
 xsltApplySequenceConstructor: A potential infinite template recursion was
 detected.
 You can adjust xsltMaxDepth (--maxdepth) in order to raise the maximum
 number of nested template calls and variables/params (currently set to
 3000).
 }}}
 and I don't as yet know how to fix that.

-- 
Ticket URL: <https://trac.macports.org/ticket/60148#comment:4>
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