[MacPorts] #57137: xcode portgroup should set -derivedDataPath on Xcode versions that need it

[MacPorts]

#57137: xcode portgroup should set -derivedDataPath on Xcode versions that need it
----------------------------+--------------------
  Reporter:  ryandesign     |      Owner:  (none)
      Type:  enhancement    |     Status:  new
  Priority:  Normal         |  Milestone:
 Component:  ports          |    Version:
Resolution:                 |   Keywords:
      Port:  xcode-1.0.tcl  |
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Comment (by kencu):

 I noticed three things that appear to be general xcode PG issues while
 fixing aquaterm and looking over irrlicht...

 1. why do we run a build phase, when the build always seems to occur again
 in the destroot phase anyway, and sometimes this causes errors?
 2. the -derivedDataPath issue
 3. at least on Xcode 10, the -derivedDataPath flag is only accepted if
 there is a scheme, which so far seems to be the same as ${xcode.targe}

 SO -- I am wondering if the xcode PG might just add the following as a
 default, as it seems to be working for me so far on several ports:
 {{{
 build                   {}
 destroot.pre_args       -derivedDataPath ./DerivedData
 xcode.scheme            ${xcode.target}
 }}}

-- 
Ticket URL: <https://trac.macports.org/ticket/57137#comment:2>
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