[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              |
------------------------------+---------------------------------

Comment (by stefan-c-kremer):

 I made the change the file.  But the result is unchanged:
 {{{
 checking readline detected... yes
 checking for bison... bison -y
 checking for flex... flex
 checking lex output file root... configure: error: cannot find output from
 flex; giving up
 Command failed:  cd
 "/opt/local/var/macports/build/_opt_local_var_macports_sources_rsync.macports.org_macports_release_tarballs_ports_devel_gmp/gmp/work/gmp-6.1.2"
 && ./configure --prefix=/opt/local --enable-cxx
 Exit code: 1
 Error: Failed to configure gmp, consult
 /opt/local/var/macports/build/_opt_local_var_macports_sources_rsync.macports.org_macports_release_tarballs_ports_devel_gmp/gmp/work/gmp-6.1.2/config.log
 Error: Failed to configure gmp: configure failure: command execution
 failed
 Error: See
 /opt/local/var/macports/logs/_opt_local_var_macports_sources_rsync.macports.org_macports_release_tarballs_ports_devel_gmp/gmp/main.log
 for details.
 Error: Follow https://guide.macports.org/#project.tickets to report a bug.
 Error: Processing of port gmp failed
 }}}

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Ticket URL: <https://trac.macports.org/ticket/55200#comment:7>
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