[MacPorts] #56971: kerberos5 @1.16.1: configure: error: cannot find output from flex; giving up

[MacPorts]

#56971: kerberos5 @1.16.1: configure: error: cannot find output from flex; giving
up
-------------------------+------------------------
  Reporter:  sealinglip  |      Owner:  ryandesign
      Type:  defect      |     Status:  assigned
  Priority:  Normal      |  Milestone:
 Component:  ports       |    Version:  2.5.3
Resolution:              |   Keywords:
      Port:  kerberos5   |
-------------------------+------------------------

Comment (by ryandesign):

 Replying to [comment:3 sealinglip]:
 > I tried the second suggestion. After executed
 >
 > {{{
 > sudo port install flex
 > }}}
 > , the problem is gone.
 >
 > Thanks a lot!

 You're welcome, though I don't understand why that worked. The build
 succeeded on our buildbot infrastructure, on all versions of macOS from
 10.5–10.13, using macOS flex (not needing MacPorts flex). I wonder if
 something unique is wrong with macOS flex on your computer. Could you show
 me the output of this command:

 {{{
 /usr/bin/flex --version
 }}}

-- 
Ticket URL: <https://trac.macports.org/ticket/56971#comment:4>
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