[MacPorts] #56631: Error: Failed to build libgcc: command execution failed on High Sierra

[MacPorts]

#56631: Error: Failed to build libgcc: command execution failed on High Sierra
--------------------------+---------------------------------
  Reporter:  DackJempsey  |      Owner:  (none)
      Type:  defect       |     Status:  new
  Priority:  Normal       |  Milestone:
 Component:  ports        |    Version:  2.5.2
Resolution:               |   Keywords:  libgcc, High Sierra
      Port:               |
--------------------------+---------------------------------

Comment (by kencu):

 It doesn't seem as though your ports are up to date. For some reason
 you're trying to download and install
 {{{
 gcc-6.3.0.tar.bz2
 }}}
 but the current version of `libgcc` is `7.3.0_1` and the current version
 of `gcc6` is `6.4.0_1`, so that file you're trying to install makes not
 much sense.

 go here:
 {{{
 cd /opt/local/var/macports/build
 }}}
 and if you see anything at all in that folder, look at the last part of
 the name for a clue as to what it is, and
 {{{
 sudo port clean
 }}}
 it.

 If there are still things in there after that
 {{{
 sudo rm -rf
 }}}
 each and every folder you see (carefully!) until that folder is completely
 and totally empty.

 Then
 {{{
 sudo port -v selfupdate
 }}}
 and watch carefully to make sure it says
 {{{
 The ports tree has been updated. To upgrade your installed ports, you
 should run
   port upgrade outdated
 }}}
 then run
 {{{
 sudo port -v upgrade outdated
 }}}
 until everything you already have installed is up to date.

 Then install gcc7
 {{{
 sudo port -v install gcc7
 }}}
 that will install `libgcc` for you as well.

 If that all goes correctly, then
 {{{
 sudo port -v install gcc6
 }}}
 and then
 {{{
 sudo port -v install gcc5
 }}}
 report back success/failure please.

-- 
Ticket URL: <https://trac.macports.org/ticket/56631#comment:1>
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