[MacPorts] #60150: portgroups cargo, cargo-fetch fail to build new port topgrade

[MacPorts]

#60150: portgroups cargo, cargo-fetch fail to build new port topgrade
-----------------------+---------------------------------
  Reporter:  lhaeger   |      Owner:  MarcusCalhoun-Lopez
      Type:  defect    |     Status:  assigned
  Priority:  Normal    |  Milestone:
 Component:  ports     |    Version:  2.6.2
Resolution:            |   Keywords:
      Port:  topgrade  |
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Comment (by MarcusCalhoun-Lopez):

 Replying to [comment:8 kencu]:
 > if you clear compiler.cpath, are the headers in /opt/local being used at
 all? If not, then we should clear the libs in /opt/local too, as you
 wouldn't want those to be used. . (which, in effect, is not using MacPorts
 at all, I guess).

 Fair point.\\
 For the sake of completeness, it might be better to add
 {{{
 compiler.cpath
 compiler.library_path
 }}}

 Since this port has no non-build MacPorts dependencies, I do not think
 this is a problem.

-- 
Ticket URL: <https://trac.macports.org/ticket/60150#comment:9>
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