BTW, just for the archives' sake: inet_client_addr() and
inet_client_port() also access MyProcPort, so they'd also have
this issue, except that they're already marked parallel-restricted.
So somebody just missed the server equivalents when marking the
parallel safety of built-in functions.
contrib/sslinfo is also full of uses of MyProcPort, but all its
functions are properly marked parallel-restricted.
I did not see any other risky-looking uses of MyProcPort in a
quick grep.
regards, tom lane