[MacPorts] #55264: libressl @2.5.5: update to 2.6.4

[MacPorts]

#55264: libressl @2.5.5: update to 2.6.4
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  Reporter:  l2dy      |      Owner:  jeremyhu
      Type:  update    |     Status:  new
  Priority:  Normal    |  Milestone:
 Component:  ports     |    Version:
Resolution:            |   Keywords:
      Port:  libressl  |
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Comment (by raimue):

 Is the libressl update ABI incompatible? Or what kind of breakage do we
 expect?

 I do not think solving #54744 first would help much with the update. Even
 if openssl and libressl would coexist, and we had +openssl and +libressl
 variants in all ports, it would still be required to rev-bump dependents
 for ABI incompatible changes.

 On ABI incompatible updates, we are usually rev-bumping dependents that
 use it by default. If people chose to install a non-default port to
 fulfill a dependency, we have no better solution to offer than to live
 with the occasional brokenness. If rev-upgrade can detect the
 incompatibility by examining the libraries (failing at load, not at
 runtime), then it will automatically rebuild the broken ports locally.

-- 
Ticket URL: <https://trac.macports.org/ticket/55264#comment:11>
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