[MacPorts] #63960: audacity: strange sdkroot selection

[MacPorts]

#63960: audacity: strange sdkroot selection
--------------------+----------------------
 Reporter:  jmroot  |      Owner:  RJVB
     Type:  defect  |     Status:  assigned
 Priority:  Normal  |  Milestone:
Component:  ports   |    Version:
 Keywords:          |       Port:  audacity
--------------------+----------------------
 The audacity port contains this:
 {{{
 if {${os.major} >= 17} {
     # Audacity builds "normally" from 10.7 to 10.13, but will request the
 10.13 SDK
     # on 10.14 and newer to "prevent high CPU usage and slow drawing".
 Linking will
     # fail if MacPort lets source be compiled against the platform SDK, so
 we handle
     # SDK selection ourselves entirely. MP builds aren't required to
 support anything
     # but the OS version they were built for. On 11.x we just build as if
 there are
     # no OS specifics.
     if {${os.major} < 20} {
         macosx_deployment_target 10.13
         configure.sdkroot
     }
 }
 }}}
 The comment makes it sound like the intent is to build against the 10.13
 SDK. But what actually happens is `configure.sdkroot` is cleared while
 leaving `configure.sdk_version` at its default value, which means:
  1. the port will be built against `MacOSX.sdk`, which will be an
 indeterminate SDK version, and
  2. a warning will be printed because the requested SDK version is not
 what ended up in `configure.sdkroot`.

 What is actually intended to happen here?

-- 
Ticket URL: <https://trac.macports.org/ticket/63960>
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