pgsql: Avoid 0-length memcpy to NULL with EXEC_BACKEND - Mailing list pgsql-committers

Avoid 0-length memcpy to NULL with EXEC_BACKEND

memcpy(NULL, src, 0) is forbidden by POSIX, even though every
production version of libc allows it. Let's be tidy.

Per report from Thomas Munro, running UBSan with EXEC_BACKEND.
Backpatch to v17, where this code was added.

Discussion:
https://www.postgresql.org/message-id/CA%2BhUKG%2Be-dV7YWBzfBZXsgovgRuX5VmvmOT%2Bv0aXiZJ-EKbXcw@mail.gmail.com

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/f3412a61f3f92d795ce0c8bb715831ec02124bfb

Modified Files
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src/backend/postmaster/launch_backend.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)