[MacPorts] #52469: Rust update to 1.12

[MacPorts]

#52469: Rust update to 1.12
-----------------------+----------------------
  Reporter:  jboone@…  |      Owner:  g5pw@…
      Type:  update    |     Status:  new
  Priority:  Normal    |  Milestone:
 Component:  ports     |    Version:  2.3.4
Resolution:            |   Keywords:  haspatch
      Port:  rust      |
-----------------------+----------------------

Comment (by raimue@…):

 Works fine for me on 10.12 Sierra and would resolve #52247, where you
 mentioned it does not work on 10.11 El Capitan.

-- 
Ticket URL: <https://trac.macports.org/ticket/52469#comment:3>
MacPorts <https://www.macports.org/>
Ports system for the Mac operating system