pgsql: Initialize index stats during parallel VACUUM.

Initialize index stats during parallel VACUUM.

Initialize shared memory allocated for index stats to avoid a hard
crash. This was possible when parallel VACUUM became confused about the
current phase of index processing.

Oversight in commit 8e1fae1938, which refactored parallel VACUUM.

Author: Masahiko Sawada <sawada(dot)mshk(at)gmail(dot)com>
Reported-By: Justin Pryzby <pryzby(at)telsasoft(dot)com>
Discussion: https://postgr.es/m/20220818133406.GL26426@telsasoft.com
Backpatch: 15-, the first version with the refactoring commit.

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/662ba729a67e5c6e43efbc5263e1d2c3a72a8741

Modified Files
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src/backend/commands/vacuumparallel.c | 1 +
1 file changed, 1 insertion(+)