pgsql: CheckNNConstraintFetch: Fill all of ConstrCheck in a single pass

CheckNNConstraintFetch: Fill all of ConstrCheck in a single pass

Previously, we'd fill all fields except ccbin, and only later obtain and
detoast ccbin, with hypothetical failures being possible. If ccbin is
null (rare catalog corruption I have never witnessed) or its a corrupted
toast entry, we leak a tiny bit of memory in CacheMemoryContext from
having strdup'd the constraint name. Repair these by only attempting to
fill the struct once ccbin has been detoasted.

Author: Ranier Vilela <ranier(dot)vf(at)gmail(dot)com>
Discussion: https://postgr.es/m/CAEudQAr=i3_Z4GvmediX900+sSySTeMkvuytYShhQqEwoGyvhA@mail.gmail.com

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/94f95d91b025cb6752b4118bb0b30851e3d64df9

Modified Files
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src/backend/utils/cache/relcache.c | 12 ++++++------
1 file changed, 6 insertions(+), 6 deletions(-)