On opensuse-factory list I reported sudo not executing its argument on some
Factory systems.

It turned out that, unlike 13.2, Factory needs the CONFIG_AUDIT=y kernel config
option:

socket(PF_NETLINK, SOCK_RAW, NETLINK_AUDIT) = -1 EPROTONOSUPPORT (Protocol not
supported)
setresuid32(-1, -1, -1)                 = 0
setresgid32(-1, -1, -1)                 = 0
close(3)                                = 0
close(4)                                = 0
exit_group(1)                           = ?
+++ exited with 1 +++

So it seems that in absence of that kernel support, sudo does not provide any
informative error message to the user. I would expect it to print that to
stderr, like it does when strace sudo results in a uid other than root's.