[MacPorts] #63092: Allow ports to install for x86_64 on arm64 if a dependency requires that

[MacPorts]

#63092: Allow ports to install for x86_64 on arm64 if a dependency requires that
------------------------+--------------------
 Reporter:  ryandesign  |      Owner:  (none)
     Type:  defect      |     Status:  new
 Priority:  Normal      |  Milestone:
Component:  base        |    Version:  2.7.1
 Keywords:              |       Port:
------------------------+--------------------
 On arm64, I'm able to install a port that supports x86_64 but not arm64:
 {{{
 % uname -m
 arm64
 % port -v installed oracle-instantclient
 The following ports are currently installed:
   oracle-instantclient @11.2.0.4.0_1 (active) requested_variants=''
 platform='darwin 20' archs='x86_64' date='2021-06-14T11:07:42+0000'
 }}}
 However, I'm not able to install a port that depends on that port:
 {{{
 % sudo port install php80-oracle
 --->  Computing dependencies for php80-oracle
 Error: Cannot install php80-oracle for the arch 'arm64' because
 Error: its dependency oracle-instantclient only supports the archs 'x86_64
 i386'.
 Error: Follow https://guide.macports.org/#project.tickets if you believe
 there is a bug.
 Error: Processing of port php80-oracle failed
 }}}
 Why not? Why can't MacPorts install php80-oracle for x86_64, just like it
 did for its dependency oracle-instantclient?

-- 
Ticket URL: <https://trac.macports.org/ticket/63092>
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