pgsql: Remove overzealous assertion from PHJ.

Remove overzealous assertion from PHJ.

We can't assert that we're the only process attached to a barrier after
BarrierArriveAndDetachExceptLast(). Although that'll be true almost
always, a late-starting parallel worker can attach very briefly (that
is, immediately detach after checking the phase) right at that moment.
BarrierArriveAndDetachExceptLast() already contains an assertion like
that, but it holds a spinlock preventing the race. This thinko caused a
one-off failure on build farm animal chimaera.

Diagnosed-by: Melanie Plageman <melanieplageman(at)gmail(dot)com>
Reported-by: Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us>
Discussion: https://postgr.es/m/3590249.1680971629@sss.pgh.pa.us

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/b37d051b0e59e4324e346655a27509507813db79

Modified Files
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src/backend/executor/nodeHash.c | 1 -
1 file changed, 1 deletion(-)