pgsql: pg_dump: check for _beginthreadex() failure in parallel dump

pg_dump: check for _beginthreadex() failure in parallel dump

ParallelBackupStart() stored _beginthreadex()'s return value as the
worker's thread handle without checking it. On failure that value is 0,
which would later reach WaitForMultipleObjects() as a null handle, caught
only by an Assert. The fork() path already calls pg_fatal() when it
fails; do the same for _beginthreadex(), as pgbench does.

Author: Bryan Green <dbryan(dot)green(at)gmail(dot)com>
Discussion: https://www.postgresql.org/message-id/8c712d76-ecf7-4749-a6d8-dddc01f298ec@gmail.com
Backpatch-through: 14

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/75e201bf95d8825f1c025792eed0f13d65657c5d

Modified Files
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src/bin/pg_dump/parallel.c | 2 ++
1 file changed, 2 insertions(+)