Avoid double transformation of json_array()'s subquery. transformJsonArrayQueryConstructor() applied transformStmt() to the same subquery tree twice. While this causes no issue in many cases, there are some where it causes a coredump, thanks to the parser's habit of scribbling on its input.
Fix by making a copy before the first transformation (compare 0f43083d1). This is quite brute-force, but then so is the whole business of transforming the input twice. Per discussion in the bug thread, this implementation of json_array() parsing should be replaced completely. But that will take some work and will surely not be back-patchable, so for the moment let's take the easy way out. Oversight in 7081ac46a. Back-patch to v16 where that came in. Bug: #18877 Reported-by: Yu Liang <lu...@psu.edu> Author: Tom Lane <t...@sss.pgh.pa.us> Discussion: https://postgr.es/m/18877-c3c3ad7584583...@postgresql.org Backpatch-through: 16 Branch ------ master Details ------- https://git.postgresql.org/pg/commitdiff/e33f2335a9d9754ccf3bf7181085cfa581ee03c3 Modified Files -------------- src/backend/parser/parse_expr.c | 2 +- src/test/regress/expected/sqljson.out | 6 ++++++ src/test/regress/sql/sqljson.sql | 2 ++ 3 files changed, 9 insertions(+), 1 deletion(-)
