[MacPorts] #67806: gtk3 @3.24.38+universal: ninja: error: unknown target 'CC=/usr/bin/clang -arch arm64' (was: Error: Failed to build gtk3: command execution failed)

[MacPorts]

#67806: gtk3 @3.24.38+universal: ninja: error: unknown target 'CC=/usr/bin/clang
-arch arm64'
---------------------------+----------------------
  Reporter:  danchomichev  |      Owner:  mascguy
      Type:  defect        |     Status:  assigned
  Priority:  Normal        |  Milestone:
 Component:  ports         |    Version:
Resolution:                |   Keywords:
      Port:  gtk3          |
---------------------------+----------------------
Changes (by ryandesign):

 * owner:  (none) => mascguy
 * status:  new => assigned


Comment:

 The error in the log is:

 {{{
 :info:build ninja: error: unknown target 'CC=/usr/bin/clang -arch arm64'
 }}}

 I believe this would only occur when building with the +universal variant.
 If you don't need a universal build, you could avoid the problem by not
 using the universal variant. However, maybe you do need to build
 universal, in which case we should fix this.

 I am also confused by a message earlier at the end of the configure phase:

 {{{
 :debug:configure Executing proc-pre-org.macports.configure-configure-2
 :error:configure gtk3 requires at least one architecture runnable on this
 :error:configure machine to be able to build universally. Please add at
 least
 :error:configure one of the following architectures to `universal_archs`
 in
 :error:configure "/opt/local/etc/macports/macports.conf":
 :error:configure        ppc64 ppc
 }}}

 I note that the code in the gtk3 Portfile that prints this message has not
 been updated for the arm64 architecture, so this message may be
 spurious—or updating that code may be needed to get this port to build
 universal. There are several related gtk ports; they may all need updates.
 Best not to let them diverge too much.

-- 
Ticket URL: <https://trac.macports.org/ticket/67806#comment:3>
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