David Rowley <dgrowle...@gmail.com> writes: > On Wed, 8 May 2024 at 10:55, Tom Lane <t...@sss.pgh.pa.us> wrote: >> Not in a way that gives me any confidence that we found *all* the >> problems.
> Here are some statements I believe to be true: > 1. If REALLOCATE_BITMAPSETS is defined then modifications to a > Bitmapset will make a copy and free the original. > 2. If a query runs successfully without REALLOCATE_BITMAPSETS and > Assert fails due to an invalid Bitmapset when REALLOCATE_BITMAPSETS is > defined, then we have > 1 pointer pointing to the same set and not all > of them are being updated when the members are added/removed. > Given the above, I can't see what Bitmapset sharing problems we won't > find with REALLOCATE_BITMAPSETS. Anything where the trouble spots are in a code path we fail to exercise with our available test suites. If you think there are no such code paths, I'm sorry to disillusion you. I spent a little bit of time wondering if we could find problems in a more static way by marking bitmapset fields as "const", but I fear that would create a huge number of false positives. regards, tom lane