Python's subprocess module has a race condition: Popen() constructor has a call to global "_cleanup()" function on whenever a Popen object gets created, and that call causes a check for all pending Popen objects whether their subprocess has exited - i.e. the poll() method is called for every active Popen object. See http://bugs.python.org/issue1731717 for addition details SCon's compat/_scons_subprocess.py module is just a copy of a more recent stock Python subprocess.py modified so it will work with older Python versions. The attached patch will add locks around calls to Popen and change the compat module in a way that the subprocess module is always used, no matter if Python already ships one. The rationale behind this decision is that there are many Python versions in the wild with different Popen() race condition problems. Fix: Patch attached with submission follows: How-To-Repeat: Run scons -j8 on a quad core machine
Responsible Changed From-To: freebsd-ports-bugs->pgollucci Over to maintainer (via the GNATS Auto Assign Tool)
State Changed From-To: open->closed Committed. Thanks!
pgollucci 2008-12-25 14:57:06 UTC FreeBSD ports repository Modified files: devel/scons Makefile Added files: devel/scons/files patch-engine-SCons-compat-__init__.py patch-engine-SCons-compat-_scons_subprocess.py Log: Python's subprocess module has a race condition: Popen() constructor has a call to global "_cleanup()" function on whenever a Popen object gets created, and that call causes a check for all pending Popen objects whether their subprocess has exited - i.e. the poll() method is called for every active Popen object. See http://bugs.python.org/issue1731717 for addition details SCon's compat/_scons_subprocess.py module is just a copy of a more recent stock Python subprocess.py modified so it will work with older Python versions. The attached patch will add locks around calls to Popen and change the compat module in a way that the subprocess module is always used, no matter if Python already ships one. The rationale behind this decision is that there are many Python versions in the wild with different Popen() race condition problems. PR: ports/128845 Submitted by: Steven Kreuzer <skreuzer@exit2shell.com> Approved by: araujo (mentor, implicit) Revision Changes Path 1.35 +1 -0 ports/devel/scons/Makefile 1.1 +29 -0 ports/devel/scons/files/patch-engine-SCons-compat-__init__.py (new) 1.1 +33 -0 ports/devel/scons/files/patch-engine-SCons-compat-_scons_subprocess.py (new) _______________________________________________ cvs-all@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/cvs-all To unsubscribe, send any mail to "cvs-all-unsubscribe@freebsd.org"