Message300052
To build python for embedded Linux systems,
(http://www.yoctoproject.org/docs/2.3.1/yocto-project-qs/yocto-project-qs.html)
The 32-bit python's multiprocessing.BoundedSemaphore could not work.
1. Prerequisite
- Build 32bit python on 64bit host, add '-m32' to gcc
- Cross compling on linux platform, not have `-pthread'
In configure.ac, ac_cv_pthread=no while cross compiling
...
2001 AC_MSG_CHECKING(whether $CC accepts -pthread)
2002 AC_CACHE_VAL(ac_cv_pthread,
2003 [ac_save_cc="$CC"
2004 CC="$CC -pthread"
2005 AC_RUN_IFELSE([AC_LANG_SOURCE([[
[snip]
2018 ]])],[ac_cv_pthread=yes],[ac_cv_pthread=no],[ac_cv_pthread=no])
...
— Macro: AC_RUN_IFELSE (input, [action-if-true], [action-if-false], [action-if-cross-compiling])
2. Reproduce with simplifying the prerequisite
$ git clone https://github.com/python/cpython.git; cd ./cpython
$ ac_cv_pthread=no CC="gcc -m32" ./configure
$ make -j 10
$ ./python -c "import multiprocessing; pool_sema = multiprocessing.BoundedSemaphore(value=1); pool_sema.acquire(); pool_sema.release()"
Traceback (most recent call last):
File "<string>", line 1, in <module>
ValueError: semaphore or lock released too many times
And the issue also caused invoking put of 'multiprocessing.Queue' hung.
$ ./python -c "import multiprocessing; queue_instance = multiprocessing.Queue(); queue_instance.put(('install'))" |
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Date |
User |
Action |
Args |
2017-08-10 07:21:56 | hongxu | set | recipients:
+ hongxu |
2017-08-10 07:21:56 | hongxu | set | messageid: <1502349716.95.0.155037219321.issue31171@psf.upfronthosting.co.za> |
2017-08-10 07:21:56 | hongxu | link | issue31171 messages |
2017-08-10 07:21:56 | hongxu | create | |
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