pgsql: Silence Valgrind complaint with EXEC_BACKEND

Silence Valgrind complaint with EXEC_BACKEND

The padding bytes written to the backend params file were
uninitialized. That's harmless because we don't access the padding
bytes when we read the file back in, but Valgrind doesn't know
that. In any case, clear the padding bytes to make Valgrind happy.

Reported-by: Alexander Lakhin
Discussion: https://www.postgresql.org/message-id/014768ed-8b39-c44f-b07c-098c87b1644c@gmail.com

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/b19890d49d122257ddcdb7ab2c5038f5075906c1

Modified Files
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src/backend/postmaster/postmaster.c | 8 ++++++++
1 file changed, 8 insertions(+)