[MacPorts] #55200: gmp @6.1.2 configure: error: cannot find output from flex; giving up

[MacPorts]

#55200: gmp @6.1.2 configure: error: cannot find output from flex; giving up
------------------------------+---------------------------------
  Reporter:  stefan-c-kremer  |      Owner:  MarcusCalhoun-Lopez
      Type:  defect           |     Status:  assigned
  Priority:  Normal           |  Milestone:
 Component:  ports            |    Version:
Resolution:                   |   Keywords:
      Port:  gmp              |
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Comment (by stefan-c-kremer):

 '''Solved! '''
 {{{
 sudo port -v install m4
 sudo port -v clean gmp
 sudo port -v install gmp
 sudo port -f activate gmp
 }}}
 Is there a missing dependency between gmp and m4?
 I got a hint here: https://trac.macports.org/ticket/36450

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Ticket URL: <https://trac.macports.org/ticket/55200#comment:11>
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