On Thu, Aug 31, 2023 at 5:34 PM Richard Guo <guofengli...@gmail.com> wrote: > > While working on a bug in expandRecordVariable() I noticed that in the > switch statement for case RTE_SUBQUERY we initialize struct ParseState > with {0} while for case RTE_CTE we do that with MemSet. I understand > that there is nothing wrong with this, just cannot get away with the > inconsistency inside the same function (sorry for the nitpicking). > > Do we have a preference for how to initialize structures? From 9fd45870 > it seems that we prefer to {0}. So here is a trivial patch doing that. > And with a rough scan the MemSet calls in pg_stat_get_backend_subxact() > can also be replaced with {0}, so include that in the patch too. > > Thanks > Richard
If the struct has padding or aligned, {0} only guarantee the struct members initialized to 0, while memset sets the alignment/padding to 0 as well, but since we will not access the alignment/padding, so they give the same effect. I bet {0} should be faster since there is no function call, but I'm not 100% sure ;) -- Regards Junwang Zhao