[issue32818] multiprocessing segmentfault under Windows compatibility mode

Change by Segev Finer : -- keywords: +patch pull_requests: +5716 stage: -> patch review ___ Python tracker ___ ___ Python-bugs-list

[issue32818] multiprocessing segmentfault under Windows compatibility mode

Segev Finer added the comment: Windows seems to dereference lpStartupInfo->lpAttributeList, despite it being NULL since we had no attributes to set. Smells like a Windows bug in the compatibility shim, since it doesn't crash in non compatibility mode. Not setting EXTENDED_STARTUPINFO_PRESENT

[issue32818] multiprocessing segmentfault under Windows compatibility mode

Ma Lin added the comment: 3.7.0 beta2 still segmentfault. Finer, please have a look. segmentfault conditions: 64bit Windows 10 (1709) + 32bit Python 3.7.0 Beta2 + Compatibility Mode enabled. (64bit Python doesn't segmentfault) -- nosy: +Segev Finer

[issue32818] multiprocessing segmentfault under Windows compatibility mode

Ma Lin added the comment: Git bisect says this is the first bad commit: https://github.com/python/cpython/commit/b2a6083eb0384f38839d3f1ed32262a3852026fa -- ___ Python tracker

[issue32818] multiprocessing segmentfault under Windows compatibility mode

Ma Lin added the comment: segmentfault conditions: 64bit Windows + 32bit Python + Compatibility Mode enabled. some infomation: 1, 64bit Python doesn't segmentfault. 2, 3.7.0a3 is ok, 3.7.0a4 segmentfaults. 3, unrelated to Windows SDK, switch from 1709 SDK to 1703 SDK also segmentfaults. -

[issue32818] multiprocessing segmentfault under Windows compatibility mode

Ma Lin added the comment: Here is two traceback messages: D:\git\cpython\PCbuild\win32>python.exe -X dev d:\git\cpython\Lib\test\test_multiprocess ing_main_handling.py ssF == FAIL: test_basi

[issue32818] multiprocessing segmentfault under Windows compatibility mode

New submission from Ma Lin : Reproduce: Right click python.exe -> properties -> compatibility tab -> enable compatibility mode (e.g. Windows 7) Then run this test will get a segmentfault: test_multiprocessing_main_handling.py CPython 3.6 is Ok. -- components: Windows messages: 311980