Obviously you've got a problem if your getting a segfault and it sounds from your description that it is happening when you have multiple active statements. I have yet to see a good example of doing updates/deletes/inserts in a loop on a result-set that is not better written another way. If it wasn't SQLite then even if you cannot easily do them in one go in plain SQL you probably could in a procedure.

You should perhaps consider producing a small self contained example producing the segfault so it can be reported for SQLite but in any case I'd try very hard to do your updates/deletes/inserts in one piece of SQL if you can and avoid multiple active statements.