我很难在 macports 中升级libunwind-headers端口。我已经查看了上一篇关于此的帖子：
sudo xcodebuild -license agree
这并没有解决问题。
这是我的终端输出：
new-host-2 [~] % sudo port upgrade outdated
---> Extracting libunwind-headers
Error: org.macports.extract for port libunwind-headers returned: command execution failed
Please see the log file for port libunwind-headers for details:
/opt/local/var/macports/logs/_opt_local_var_macports_sources_rsync.macports.org_release_ports_devel_libunwind-headers/libunwind-headers/main.log
Error: Problem while installing libunwind-headers
To report a bug, follow the instructions in the guide:
http://guide.macports.org/#project.tickets
这是我的日志文件：
version:1
:debug:main libunwind-headers has no conflicts
:debug:main Executing org.macports.main (libunwind-headers)
:debug:main changing euid/egid - current euid: 0 - current egid: 0
:debug:main egid changed to: 501
:debug:main euid changed to: 502
:debug:main Skipping completed org.macports.archivefetch (libunwind-headers)
:debug:main Privilege de-escalation not attempted as not running as root.
:debug:main Skipping completed org.macports.fetch (libunwind-headers)
:debug:main Privilege de-escalation not attempted as not running as root.
:debug:main Skipping completed org.macports.checksum (libunwind-headers)
:debug:main Privilege de-escalation not attempted as not running as root.
:debug:extract extract phase started at Wed Nov 6 12:42:26 EST 2013
:notice:extract ---> Extracting libunwind-headers
:debug:extract Executing org.macports.extract (libunwind-headers)
:info:extract ---> Extracting libunwind-35.1.tar.gz
:debug:extract setting option extract.args to '/opt/local/var/macports/distfiles/libunwind-headers/libunwind-35.1.tar.gz'
:debug:extract Environment: CPATH='/opt/local/include' CC_PRINT_OPTIONS_FILE='/opt/local/var/macports/build/_opt_local_var_macports_sources_rsync.mac ports.org_release_ports_devel_libunwind-headers/libunwind-headers/work/.CC_PRINT_OPTIONS' LIBRARY_PATH='/opt/local/lib' CC_PRINT_OPTIONS='YES' MACOSX_DEPLOYMENT_TARGET='10.9'
:debug:extract Assembled command: 'cd "/opt/local/var/macports/build/_opt_local_var_macports_sources_rsync.macports.org_release_ports_devel_libunwind-headers/libunwind-headers/work" && /usr/bin/gzip -dc '/opt/local/var/macports/distfiles/libunwind-headers/libunwind-35.1.tar.gz' | /usr/bin/gnutar --no-same-owner -xf -'
:debug:extract Executing command line: cd "/opt/local/var/macports/build/_opt_local_var_macports_sources_rsync.macports.org_release_ports_devel_libunwind-headers/libunwind-headers/work" && /usr/bin/gzip -dc '/opt/local/var/macports/distfiles/libunwind-headers/libunwind-35.1.tar.gz' | /usr/bin/gnutar --no-same-owner -xf -
:info:extract sh: /usr/bin/gnutar: No such file or directory
:info:extract gzip: error writing to output: Broken pipe
:info:extract gzip: /opt/local/var/macports/distfiles/libunwind-headers/libunwind-35.1.tar.gz: uncompress failed
:info:extract Command failed: cd "/opt/local/var/macports/build/_opt_local_var_macports_sources_rsync.macports.org_release_ports_devel_libunwind-headers/libunwind-headers/work" && /usr/bin/gzip -dc '/opt/local/var/macports/distfiles/libunwind-headers/libunwind-35.1.tar.gz' | /usr/bin/gnutar --no-same-owner -xf -
:info:extract Exit code: 127
:error:extract org.macports.extract for port libunwind-headers returned: command execution failed
:debug:extract Error code: NONE
:debug:extract Backtrace: command execution failed
while executing
"$procedure $targetname"
:info:extract Warning: targets not executed for libunwind-headers: org.macports.activate org.macports.extract org.macports.patch org.macports.configure org.macports.build org.macports.destroot org.macports.install
:notice:extract Please see the log file for port libunwind-headers for details:
/opt/local/var/macports/logs/_opt_local_var_macports_sources_rsync.macports.org_release_ports_devel_libunwind-headers/libunwind-headers/main.log
这看起来像一个错误，还是我做错了什么？我也尝试过清理它，然后卸载/重新安装它。
自我更新也没有返回任何错误。
sudo port -v selfupdate