[MacPorts] #60724: gnucash fails to build ("uses the cxx11 PortGroup which is deprecated")

[MacPorts]

#60724: gnucash fails to build ("uses the cxx11 PortGroup which is deprecated")
--------------------+---------------------
 Reporter:  posita  |      Owner:  (none)
     Type:  defect  |     Status:  new
 Priority:  Normal  |  Milestone:
Component:  ports   |    Version:  2.6.2
 Keywords:          |       Port:  gnucash
--------------------+---------------------
 {{{
 % sudo port -N -c install \gnucash
 Password:
 --->  Computing dependencies for gnucash
 --->  Fetching distfiles for gnucash
 --->  Attempting to fetch gnucash-3.9.tar.bz2 from
 https://ayera.dl.sourceforge.net/gnucash
 --->  Verifying checksums for gnucash
 --->  Extracting gnucash
 --->  Configuring gnucash
 Warning:
 -----------------------------------------------------------------------
 Warning: The port 'gnucash' uses the cxx11 PortGroup which is deprecated.
 Warning: Please instead specify the required c++ standard directly using
 Warning:     compiler.cxx_standard  2011
 Warning: replacing 2011 with newer standards (e.g. 2014, 2017) as
 required.
 Warning: For more details see
 https://trac.macports.org/wiki/CompilerSelection
 Warning:
 -----------------------------------------------------------------------
 Error: Failed to configure gnucash: configure failure: command execution
 failed
 Error: See /opt/local/macports-20200625/var/macports/logs
 /_opt_local_macports-
 20200625_var_macports_sources_rsync.macports.org_macports_release_tarballs_ports_gnome_gnucash/gnucash/main.log
 for details.
 Error: Follow https://guide.macports.org/#project.tickets to report a bug
 }}}

 After reading wiki:CompilerSelection, it's still unclear what action to
 take as a user. Is that something I can do as a command line parameter or
 environment variable passed to `port install …`? All the applicable
 instructions seem to recommend `Portfile` modifications.

-- 
Ticket URL: <https://trac.macports.org/ticket/60724>
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