Don't dump core when destroying an unused ParallelContext.
If a transaction or subtransaction creates a ParallelContext but ends
without calling InitializeParallelDSM, the previous code would
seg fault. Fix that.
Branch
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REL9_5_STABLE
Details
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http://git.postgresql.org/pg/commitdiff/91d97f03ca2a9ed56b322b69dde0392db835f722
Modified Files
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src/backend/access/transam/parallel.c | 17 ++++++++++-------
1 file changed, 10 insertions(+), 7 deletions(-)