[MacPorts] #63527: fftw @2.1.5_9 +gfortran: Fails to build on M1 with error in configure stage

[MacPorts]

#63527: fftw @2.1.5_9 +gfortran: Fails to build on M1 with error in configure stage
--------------------+--------------------
 Reporter:  p-bro   |      Owner:  (none)
     Type:  defect  |     Status:  new
 Priority:  Normal  |  Milestone:
Component:  ports   |    Version:  2.7.1
 Keywords:          |       Port:  fftw
--------------------+--------------------
 Fault happens on Apple M1 running Big Sur 11.6. The relevant section in
 the log file is
 {{{
 :info:configure checking build system type... configure: error: /bin/sh
 ./config.sub -apple-darwin20.6.0 failed
 :info:configure configure: WARNING: cache variable ac_cv_build contains a
 newline
 :info:configure Command failed:  cd
 "/opt/local/var/macports/build/_opt_local_var_macports_sources_rsync.macports.org_macports_release_tarballs_ports_math_fftw/fftw/work/fftw-2.1.5"
 && ./configure --prefix=/opt/local --enable-type-prefix --enable-threads
 --enable-fortran --infodir=/opt/local/share/info --enable-shared
 }}}
 I think that may be the configure file's unfamiliarity with the
 architecture.

 As this port has no maintainer, I'm probably pretty much shouting in the
 void, but I'm recording it here for completeness. Full log attached.

-- 
Ticket URL: <https://trac.macports.org/ticket/63527>
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