En un esfuerzo para

sudo port install gcc47

Parece que me estoy perdiendo

cctoolsld64encabezados de libunwind

donde ambos

cctoolsld64

depender de

encabezados de libunwind

Al tratar de

sudo port install libunwind-headers

Yo obtengo:

--->  Building libunwind-headers
Error: org.macports.build 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_tarballs_ports_devel_libunwind-headers/libunwind-headers/main.log
To report a bug, follow the instructions in the guide:
    http://guide.macports.org/#project.tickets
Error: Processing of port libunwind-headers failed

El archivo de registro dice:

25 :info:build Command failed: cd "/opt/local/var/macports/build/_opt_local_var_macports_sources_rsync.macports.org_release_tarballs_ports_devel_libunwind-headers    /libunwind-headers/work/libunwind-30" && /usr/bin/xcodebuild  -target "libunwind-ld" -configuration Deployment build OBJROOT=build/ SYMROOT=build/ MACOSX_DEPLO    YMENT_TARGET=10.8 ARCHS= SDKROOT="" GCC_VERSION=com.apple.compilers.llvm.clang.1_0
 26 :info:build Exit code: 69
 27 :error:build org.macports.build for port libunwind-headers returned: command execution failed
 28 :debug:build Error code: NONE
 29 :debug:build Backtrace: command execution failed
 30     while executing
 31 "$procedure $targetname"
 32 :info:build Warning: targets not executed for libunwind-headers: org.macports.activate org.macports.build org.macports.destroot org.macports.install
 33 :notice:build Please see the log file for port libunwind-headers for details:
 34     /opt/local/var/macports/logs/_opt_local_var_macports_sources_rsync.macports.org_release_tarballs_ports_devel_libunwind-headers/libunwind-headers/main.log

¿Cómo debo proceder con esto por favor?