Trace mode and symlinked prefix

[Davide Liessi]

Hi all.

I have /opt/frescobaldi/64 symlinked to
/Volumes/MacPorts/frescobaldi/64 and I installed MacPorts in
/opt/frescobaldi/64.

Trace mode fails in this setting.
E.g., trying to upgrade ncurses I get the following (which succeeds
without trace mode):

$ pwd
/opt/frescobaldi/64
$ sudo bin/port -t upgrade ncurses
--->  Fetching distfiles for ncurses
--->  Verifying checksums for ncurses
--->  Extracting ncurses
Error: Failed to extract ncurses: command execution failed
Error: See /opt/frescobaldi/64/var/macports/logs/_opt_macports-git_macports-ports_devel_ncurses/ncurses/main.log
for details.
Error: Follow https://guide.macports.org/#project.tickets to report a bug.
$ bin/port log ncurses | tail -n20
--->  Extracting ncurses-6.1.tar.gz
DEBUG: setting option extract.args to
'/Volumes/MacPorts/distfiles/ncurses/ncurses-6.1.tar.gz'
DEBUG: Environment:
DEBUG: CC_PRINT_OPTIONS='YES'
DEBUG: CC_PRINT_OPTIONS_FILE='/Volumes/MacPorts/frescobaldi/64/var/macports/build/_opt_macports-git_macports-ports_devel_ncurses/ncurses/work/.CC_PRINT_OPTIONS'
DEBUG: CPATH='/opt/frescobaldi/64/include'
DEBUG: LIBRARY_PATH='/opt/frescobaldi/64/lib'
DEBUG: MACOSX_DEPLOYMENT_TARGET='10.11'
Executing:  cd "/Volumes/MacPorts/frescobaldi/64/var/macports/build/_opt_macports-git_macports-ports_devel_ncurses/ncurses/work"
&& /usr/bin/gzip -dc
'/Volumes/MacPorts/distfiles/ncurses/ncurses-6.1.tar.gz' |
/usr/bin/tar -xf -
DEBUG: system:  cd
"/Volumes/MacPorts/frescobaldi/64/var/macports/build/_opt_macports-git_macports-ports_devel_ncurses/ncurses/work"
&& /usr/bin/gzip -dc
'/Volumes/MacPorts/distfiles/ncurses/ncurses-6.1.tar.gz' |
/usr/bin/tar -xf -
sip_copy_proc: mkdir(/opt/frescobaldi/64/var/macports/sip-workaround/502/bin):
Operation not permitted
sandbox-exec: sh: Operation not permitted
Command failed:  cd
"/Volumes/MacPorts/frescobaldi/64/var/macports/build/_opt_macports-git_macports-ports_devel_ncurses/ncurses/work"
&& /usr/bin/gzip -dc
'/Volumes/MacPorts/distfiles/ncurses/ncurses-6.1.tar.gz' |
/usr/bin/tar -xf -
Exit code: 71
Error: Failed to extract ncurses: command execution failed
DEBUG: Error code: NONE
DEBUG: Backtrace: command execution failed
DEBUG:     while executing
DEBUG: "$procedure $targetname"
Error: See /opt/frescobaldi/64/var/macports/logs/_opt_macports-git_macports-ports_devel_ncurses/ncurses/main.log
for details.

I know this is not a supported configuration, but based on [1] I
understand that this is still considered a bug, at least by Clemens.

Is my understanding correct?
Is there anything I could do to make trace mode work in my setting?

Best wishes.
Davide

[1] https://lists.macports.org/pipermail/macports-users/2015-January/037817.html