New submission from Jose Fonseca <jose.r.fons...@gmail.com>: MSVCRT's implementation of _spawnve, _spawnvpe, or any version that takes an environ as paramater is not thread-safe, because it stores a temporary environment string into a global variable.
_spawnve, _spawnvpe, and friends call a function named _cenvarg which concatenate the environment strings into a global variable called _aenvptr, which gets free'd and zero'd after each invocation. This was causing random build failures in scons when parallel build (-j) was enabled. The sample application evidences this problem. It also includes a simple workaround in python, by acquiring a global lock around os.spawnve, and simulating P_WAIT with P_NOWAIT to avoid holding the global lock while the child process is running. I believe something along these lines should be done for CPython on Windows. ---------- components: Interpreter Core files: spawnve.py messages: 90495 nosy: jfonseca severity: normal status: open title: MSVCRT's spawnve/spawnvpe are not thread safe type: crash versions: Python 2.4, Python 2.5, Python 2.6 Added file: http://bugs.python.org/file14495/spawnve.py _______________________________________ Python tracker <rep...@bugs.python.org> <http://bugs.python.org/issue6476> _______________________________________ _______________________________________________ Python-bugs-list mailing list Unsubscribe: http://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
