py27-pygtksourceview fail to build on macOS 11.2.3 Big Sur

[gagarine (Simon)]

I tried to install ​https://ports.macports.org/port/cherrytree/ but it fails when building py27-pygtksourceview dependency.

End of the log:

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:info:build       __wrap_gtk_source_iter_backward_search in gtksourceview2_la-gtksourceview2.o
:info:build       __wrap_gtk_source_buffer_set_highlight_syntax in gtksourceview2_la-gtksourceview2.o
:info:build       __wrap_gtk_source_buffer_set_highlight_matching_brackets in gtksourceview2_la-gtksourceview2.o
:info:build       __wrap_gtk_source_buffer_set_max_undo_levels in gtksourceview2_la-gtksourceview2.o
:info:build       __wrap_gtk_source_buffer_set_language in gtksourceview2_la-gtksourceview2.o
:info:build       __wrap_gtk_source_buffer_undo in gtksourceview2_la-gtksourceview2.o
:info:build       ...
:info:build ld: symbol(s) not found for architecture x86_64
:info:build clang: error: linker command failed with exit code 1 (use -v to see invocation)
:info:build make[2]: *** [gtksourceview2.la] Error 1
:info:build make[2]: Leaving directory `/opt/local/var/macports/build/_opt_local_var_macports_sources_rsync.macports.org_macports_release_tarballs_ports_python_py27-pygtksourceview/py27-pygtksourceview/work/pygtksourceview-2.10.1'
:info:build make[1]: *** [all-recursive] Error 1
:info:build make[1]: Leaving directory `/opt/local/var/macports/build/_opt_local_var_macports_sources_rsync.macports.org_macports_release_tarballs_ports_python_py27-pygtksourceview/py27-pygtksourceview/work/pygtksourceview-2.10.1'
:info:build make: *** [all] Error 2
:info:build make: Leaving directory `/opt/local/var/macports/build/_opt_local_var_macports_sources_rsync.macports.org_macports_release_tarballs_ports_python_py27-pygtksourceview/py27-pygtksourceview/work/pygtksourceview-2.10.1'
:info:build Command failed:  cd "/opt/local/var/macports/build/_opt_local_var_macports_sources_rsync.macports.org_macports_release_tarballs_ports_python_py27-pygtksourceview/py27-pygtksourceview/work/pygtksourceview-2.10.1" && /usr/bin/make -j4 -w all 
:info:build Exit code: 2
:error:build Failed to build py27-pygtksourceview: command execution failed
:debug:build Error code: CHILDSTATUS 83419 2
:debug:build Backtrace: command execution failed
:debug:build     while executing
:debug:build "system {*}$notty {*}$nice $fullcmdstring"
:debug:build     invoked from within
:debug:build "command_exec build"
:debug:build     (procedure "portbuild::build_main" line 8)
:debug:build     invoked from within
:debug:build "$procedure $targetname"
:error:build See /opt/local/var/macports/logs/_opt_local_var_macports_sources_rsync.macports.org_macports_release_tarballs_ports_python_py27-pygtksourceview/py27-pygtksourceview/main.log for details.