Avoid memcpy() with same source and destination during relmapper init. A narrow reading of the C standard says that memcpy(x,x,n) is undefined, although it's hard to envision an implementation that would really misbehave. However, analysis tools such as valgrind might whine about this; accordingly, let's band-aid relmapper.c to not do it.
See also 5b630501e, d3f4e8a8a, ad7b48ea0, and other similar fixes. Apparently, none of those folk tried valgrinding initdb? This has been like this for long enough that I'm surprised it hasn't been reported before. Back-patch, just in case anybody wants to use a back branch on a platform that complains about this; we back-patched those earlier fixes too. Discussion: https://postgr.es/m/[email protected] Branch ------ REL_13_STABLE Details ------- https://git.postgresql.org/pg/commitdiff/722eb325b9511e9d0a8669112c636edebe2cb01b Modified Files -------------- src/backend/utils/cache/relmapper.c | 11 +++++++++-- 1 file changed, 9 insertions(+), 2 deletions(-)
