pgsql: Ensure gatherstate->nextreader is properly initialized.

Ensure gatherstate->nextreader is properly initialized.

The previously code worked OK as long as a Gather node was never
rescanned, or if it was rescanned, as long as it got at least as
many workers on rescan as it had originally.  But if the number
of workers ever decreased on a rescan, then it could crash.

Andreas Seltenreich

Branch
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master

Details
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http://git.postgresql.org/pg/commitdiff/53c7cff7200b6689b102f2e4a40650cf652dae39

Modified Files
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src/backend/executor/nodeGather.c | 2 ++
1 file changed, 2 insertions(+)