[MacPorts] #67359: transmission @4.0.3_1: error: redefinition of module 'libxml2'

[MacPorts]

#67359: transmission @4.0.3_1: error: redefinition of module 'libxml2'
---------------------------+----------------------------
  Reporter:  Gandoon       |      Owner:  kurthindenburg
      Type:  defect        |     Status:  assigned
  Priority:  Normal        |  Milestone:
 Component:  ports         |    Version:  2.8.1
Resolution:                |   Keywords:  catalina
      Port:  transmission  |
---------------------------+----------------------------

Comment (by Gandoon):

 I do now have a slightly clearer image of why QuickLook is involved. I
 tried to do a `port extract transmission`, chown the source directory to
 my normal user and open the code in the Xcode IDE. Now trying to build it,
 I realised the build order involving building the QuickLookPlugin first.
 When building for release, the default is to build for both Intel and
 Apple silicon. This yields linking errors that first shows up in
 QuickLookPlugin. If I either forced an Intel architecture-only build or
 defined `ONLY_ACTIVE_ARCH=YES`, the build succeeded as intended and
 finished with a built application. So there seems to be no problem with
 the Transmission source as such.

 Because I had a vague recollection of MacOS 10.15 has some issues with
 building for non-Intel architectures I further tested to add the following
 to the portfile (the second one is already somewhat included in the patch-
 file, and the second one was a try to really force only Intel code to be
 built.
 {{{
 xcode.build.settings-append   ARCHS=x86_64
 xcode.build.settings-append   ONLY_ACTIVE_ARCH=YES
 }}}
 However, adding this still does not work with the `port upgrade
 transmission` command (and yes, the options do show up on the commandline
 as instructed). The error remains exactly the same. I really cannot wrap
 my head around what is really referencing libxml2. It seems to be outside
 MacPorts ecosystem altogether, as far as I know the .modulemap referenced
 in the log is part of Apples SDK.

 So at this point I am quickly running out of ideas as to why it actually
 builds with the Xcode IDE but not with the commandline tools MacPorts
 uses.

-- 
Ticket URL: <https://trac.macports.org/ticket/67359#comment:8>
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