Thread: pgsql: Use HASH_BLOBS for xidhash.

Use HASH_BLOBS for xidhash.

This caused BufFile errors on buildfarm member sungazer, and SIGSEGV was
possible.  Conditions for reaching those symptoms were more frequent on
big-endian systems.

Discussion: https://postgr.es/m/20201129214441.GA691200@rfd.leadboat.com

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/a1b8aa1e4eec520ed8f11c3d134a7a866358d39a

Modified Files
--------------
src/backend/replication/logical/worker.c |  2 +-
src/test/perl/PostgresNode.pm            | 87 ++++++++++++++++++++++++++++++++
src/test/subscription/t/015_stream.pl    | 26 +++++++++-
3 files changed, 112 insertions(+), 3 deletions(-)