Backport fix [1] for upstream Python Issue #21704 [2]: Fix build error for
_multiprocessing when semaphores are not available.
The symptom was originally reported by RedPorts 8.4-QAT/i386,
ultimately resulting in a packaging error:
...
checking for sem_open... yes
checking for sem_timedwait... yes
checking for sem_getvalue... yes
checking for sem_unlink... yes
...
checking whether POSIX semaphores are enabled... no
checking for broken sem_getvalue... yes
...
*** WARNING: renaming "_multiprocessing" since importing it failed:
build/lib.freebsd-8.4-RELEASE-i386-3.4/_multiprocessing.so: Undefined
symbol "_PyMp_sem_unlink"
...
pkg-static: lstat(/work/a/ports/lang/python34/work/stage/usr/local/lib/
python3.4/lib-dynload/_multiprocessing.so): No such file or directory
Something is funny for Jail-based systems when it comes to host/jail
semaphore detection. A config.log would be handy to help determine why.
[1] http://hg.python.org/cpython/rev/f618f6739200
[2] http://bugs.python.org/issue21704
c0cd7bc6cc