pgsql: dict_synonym.c: remove incorrect outlen.

dict_synonym.c: remove incorrect outlen.

Previously, outlen was miscalculated if case_sensitive was false and
str_tolower() changed the byte length of the string. If outlen was too
large, pnstrdup() would stop at the NUL terminator, preventing
overrun. But if outlen was too small, it would cause truncation.

Fix by just removing outlen. It was only used in a single site, which
could just as well use pstrdup().

Discussion: https://postgre.es/m/1101e1a3afbbabb503317069c40374b82e6f4cac.camel@j-davis.com
Reviewed-by: Tristan Partin <tristan(at)partin(dot)io>
Backpatch-through: 14

Branch
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REL_16_STABLE

Details
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https://git.postgresql.org/pg/commitdiff/b32df590cce605389415c9b42b87f02bc0d623b8

Modified Files
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src/backend/tsearch/dict_synonym.c | 4 +---
1 file changed, 1 insertion(+), 3 deletions(-)