Odd LOG output from "postgres -C"

I just tested "postgres -C" on Postgres head, and got odd LOG output
lines:

    $ postgres -C shared_memory_size
    143
-->    2022-05-02 13:08:06.445 EDT [1582048] LOG:  database system is shut down

    $ postgres -C "wal_segment_size"
    16777216
-->    2022-05-02 13:13:30.499 EDT [1584650] LOG:  database system is shut down

Are those last lines expected?

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  Bruce Momjian  <bruce@momjian.us>        https://momjian.us
  EDB                                      https://enterprisedb.com

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