[MacPorts] #67292: port:clamav should use rust or compiler_wrapper PG (and the rust PG might be simplifiable)

[MacPorts]

#67292: port:clamav should use rust or compiler_wrapper PG (and the rust PG might
be simplifiable)
---------------------+--------------------
  Reporter:  RJVB    |      Owner:  (none)
      Type:  defect  |     Status:  new
  Priority:  Normal  |  Milestone:
 Component:  ports   |    Version:
Resolution:          |   Keywords:
      Port:  clamav  |
---------------------+--------------------

Comment (by pcafstockf):

 Indeed, the problem is that rust 1.7.x will not compile on 10.9 (or even
 10.13), because rust 1.7.x requires clang-16 and (at least as of
 HighSierra), clang-10 is the best we get.
 I did try the rust PG patch provided by RJVB, but it did not work for me,
 and I don't understand the MacPorts internals well enough to know why.

 I need to build `clamav` as a '''custom package binary''', which means I
 need a custom MacPorts installation to build `clamav`.
 Normally MacPorts would just install a rust 1.7.x binary package on High
 Sierra, but if you are working with a custom / multi - install, that
 doesn't work.

 Ultimately I installed standard MacPorts on High Sierra, and then
 installed the `rust` and `cargo` packages there.
 Then installed a second (custom) MacPorts with a local Portfiles
 repository containing the clamav Portfile.  I changed that Portfile from
 `port:rust` to `bin:rustc:rust`.  Basically telling the custom MacPorts to
 use rustc from the default MacPorts.
 If that weren't convoluted enough, the custom MacPorts doesn't search
 /opt/local/bin/rustc, so I had to symlink that to /usr/bin/rustc.

 But I did ultimately get a custom binary package of `clamav`.

 I've got to believe there is an easier way, and **would love to have
 somebody point out the "right" way to do it.**
 But in the meantime if you need a custom binary package of anything that
 depends on rust, I can confirm this does actually work.

-- 
Ticket URL: <https://trac.macports.org/ticket/67292#comment:5>
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