> Thanks! Please add your patch here:
>
> https://commitfest.postgresql.org/action/commitfest_view/open
>
Ok; but what about what I said about the difference between bit/string substring?
That affects overlay behaviour for bit...
I've even got
"ERROR: invalid memory alloc request size 4244635647"
with:
SELECT substring(B'1111000000000001' from 5 for -2);
(this is 8.4.2, windows version, not modified...)
test=# SELECT substring(B'1111000000000001' from 1 for -1);
substring
------------------
1111000000000001
(1 row)
test=# SELECT substring('1111000000000001' from 1 for -1);
ERROR: negative substring length not allowed