Adam Olsen <rha...@gmail.com> added the comment: The alignment requirements (long double) make it impossible to have anything in those bits.
Hypothetically, a custom allocator could lower the alignment requirements to sizeof(void *). However, rotating to the high bits is pointless as they're the least likely to be used — impossible in this case, as only the 2 highest bits would contain anything, and for that you'd need a dictionary with at least 2 billion entries on 32bit, which is more than the 32bit address space. 64-bit is similar. Note that mixing the bits back in, via XOR or similar, is actually more likely to hurt than help. It's just like ints and strings, who's hash values are very sequential, a simple shift tends to get us sequential hashes. This gives us a far lower collision rate than a statistically random hash. _______________________________________ Python tracker <rep...@bugs.python.org> <http://bugs.python.org/issue5186> _______________________________________ _______________________________________________ Python-bugs-list mailing list Unsubscribe: http://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
