New submission from Sam Price <thesampr...@gmail.com>:
if 8 1 byte fields are included in a ctype field, it allows an extra byte to be included in the packing when there is no room left for the next field. If I put the bitfields in a child structure then I get expected results. In [35]: run ctypeSizeTest.py Size is 4 Expected 3 0 0x10000 a0 0 0x10001 a1 0 0x10002 a2 0 0x10003 a3 0 0x10004 a4 0 0x10005 a5 0 0x10006 a6 0 0x10007 a7 0 0x40008 b0 <- Expected to be at offset 1, not 0. 2 0xc0000 b1 <- Expected to be at offset 1, not 2 Size is 3 Expected 3 0 0x1 a 1 0x40000 b0 1 0xc0004 b1 ---------- components: ctypes files: ctypeSizeTest.py messages: 363417 nosy: thesamprice priority: normal severity: normal status: open title: bitfield layout wrong in ctypes type: behavior versions: Python 2.7, Python 3.5, Python 3.6 Added file: https://bugs.python.org/file48954/ctypeSizeTest.py _______________________________________ Python tracker <rep...@bugs.python.org> <https://bugs.python.org/issue39858> _______________________________________ _______________________________________________ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
