pgsql: pg_upgrade: Upgrade an Assert to a real 'if' test

pg_upgrade: Upgrade an Assert to a real 'if' test

It seems possible for the condition being tested to be true in
production, and nobody would never know (except when some data
eventually becomes corrupt?).

Author: Álvaro Herrera <alvherre@alvh.no-ip.org>
Discussion: https://postgr.es/m//202109040001.zky3wgv2qeqg@alvherre.pgsql

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/3e1c942a4e2f06e9b0196180eb8fd1383e6d788e

Modified Files
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src/bin/pg_rewind/parsexlog.c | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)