[MacPorts] #55135: gcc5 @5.5.0 fails to build on Snow Leopard, Mac OS X 10.6.8, because linker command failed with undefined symbols for architecture x86_64

[MacPorts]

#55135: gcc5 @5.5.0 fails to build on Snow Leopard, Mac OS X 10.6.8, because linker
command failed with undefined symbols for architecture x86_64
------------------------+-------------------------
  Reporter:  ballapete  |      Owner:
      Type:  defect     |     Status:  new
  Priority:  Normal     |  Milestone:
 Component:  ports      |    Version:  2.4.2
Resolution:             |   Keywords:  snowleopard
      Port:  gcc5       |
------------------------+-------------------------

Comment (by ballapete):

 There must be more wrong. The build of `mediainfo` fails similarly.

 Could be I need to update the `Portfile`s from my local repository?

 {{{

                   local                                          MacPorts
 √ 1516 2017-09-13 audio/jack/Portfile            1516 2017-08-22
 audio/jack/Portfile
 • 3312 2017-07-03 devel/elftoolchain/Portfile    3190 2017-08-22
 devel/elftoolchain/Portfile
 • 1779 2017-09-13 devel/libedit/Portfile         2132 2017-10-01
 devel/libedit/Portfile
 • 3234 2017-07-03 devel/util-linux/Portfile      3240 2017-10-19 devel
 /util-linux/Portfile
 • 3380 2017-07-03 net/unbound/Portfile           3521 2017-10-16
 net/unbound/Portfile
 • 3432 2017-07-03 www/nghttp2/Portfile           3395 2017-09-21
 www/nghttp2/Portfile
 • 1082 2017-07-06 x11/blackbox/Portfile          1049 2017-08-22
 x11/blackbox/Portfile
 }}}

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Ticket URL: <https://trac.macports.org/ticket/55135#comment:7>
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