Hello, I'm neither a notmuch user or proficient in C++.
However, I noticed a bug while working on public-inbox (in Perl)
which shares Xapian thread linking logic with notmuch, and I
suspect notmuch is affected by the same problem as public-inbox.
The problem is in the _merge_threads function in add-message.cc
While the Xapian::PostingIterator for loser is iterating, the
Xapian DB is being modified by replace_document via
This was causing DatabaseCorruptError exceptions in public-inbox
with my dataset.
I fixed it in public-inbox by stashing docid scalars into a
Perl array while iterating with the PostingIterator, and then
doing lookups + replacements independently of the
PostingIterator by iterating through the Perl array: