pgsql: Fix a strict aliasing violation

Fix a strict aliasing violation

This one is almost a textbook example of an aliasing violation, and it
is straightforward to fix, so clean it up.  (The warning only shows up
if you remove the -fno-strict-aliasing option.)  Also, move the code
after the error checking.  Doesn't make a difference technically, but
it seems strange to do actions before errors are checked.

Reported-by: Tatsuo Ishii <ishii@postgresql.org>
Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://www.postgresql.org/message-id/flat/20240724.155525.366150353176322967.ishii%40postgresql.org

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/2fcc5a715130fbe9fb6eadf338e3bfe560eb0cb5

Modified Files
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src/backend/replication/logical/origin.c | 15 +++++++--------
1 file changed, 7 insertions(+), 8 deletions(-)