[MacPorts] #66288: Discussion re pre-build ports for PPC

[MacPorts]

#66288: Discussion re pre-build ports for PPC
----------------------------+-------------------------------------------
  Reporter:  barracuda156   |      Owner:  (none)
      Type:  enhancement    |     Status:  assigned
  Priority:  Normal         |  Milestone:
 Component:  buildbot/mpbb  |    Version:  2.8.0
Resolution:                 |   Keywords:  powerpc, leopard, snowleopard
      Port:                 |
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Comment (by barracuda156):

 Replying to [comment:12 ryandesign]:
 > Most ports don't have this information because MacPorts didn't have the
 capability to represent it until the release of MacPorts 2.8.0 in October
 2022 (see #15712). (Some ports use an older method of conveying this
 information, setting `known_fail yes` depending on some conditional, which
 also works. To the extent that the conditional has to do with OS versions
 only, these should be converted to use the new method as time permits.)
 >
 > In the absence of this information, all buildbot workers will try to
 build a port, and it will fail to build on the OS versions on which it
 doesn't work, and reaching this point of failure will take time (which
 could have been better spent building something that would actually
 build). Every time a port is updated, even for a trivial change that would
 not require a rebuild on OS versions where it was successful, it will
 trigger a buildbot build on those OS versions where it had previously
 failed to see if that fixed it. On an Intel Mac it may take minutes to
 activate all the dependencies and potentially many minutes or even hours
 to reach the point in a build where it fails. On a PowerPC, it would take
 much longer. I fear that any PowerPC Mac would not be able to keep up with
 the volume of commits we currently experience if it is constantly trying
 and retrying to build ports that we already know have no hope of ever
 building on such an old machine. By properly indicating minimum OS
 versions in ports, the buildbot can skip those builds on those OS versions
 within seconds and move on build a different port.
 >
 > The same applies to indicating supported architectures. For example, if
 a port only works on Intel or Apple Silicon processors, then the Portfile
 should contain the line:
 >
 > {{{
 > supported_archs arm64 i386 x86_64
 > }}}
 >

 This will be very helpful indeed to lesses the workload for a hopefully-
 to-be-added PowerPC build bot.

 I assume that everything ''requiring'' Rust, QT5+ and LLVM has a failure
 set for PowerPC? (That would be an obvious thing to do.)

 P. S. Unfortunately we also have bogus exclusions of PPC or unjustified
 requirements for Clang-only, as was shown recently, for example, with
 `poco` and `capnproto` ports.

-- 
Ticket URL: <https://trac.macports.org/ticket/66288#comment:17>
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