pgsql: Limit to_tsvector_byid's initial array allocation to something s

Limit to_tsvector_byid's initial array allocation to something sane.

The initial estimate of the number of distinct ParsedWords is just
that: an estimate.  Don't let it exceed what palloc is willing to
allocate.  If in fact we need more entries, we'll eventually fail
trying to enlarge the array.  But if we don't, this allows success on
inputs that currently draw "invalid memory alloc request size".

Per bug #18080 from Uwe Binder.  Back-patch to all supported branches.

Discussion: https://postgr.es/m/18080-d5c5e58fef8c99b7@postgresql.org

Branch
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REL_14_STABLE

Details
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https://git.postgresql.org/pg/commitdiff/a2799f53d519d6d7dba236ab02411cd232cea061

Modified Files
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src/backend/tsearch/to_tsany.c | 2 ++
1 file changed, 2 insertions(+)