ENABLE_DTRACE            unused as of a7b7b07a
HAVE_ERR_SET_MARK        unused as of 4ed4b6c5
HAVE_FCVT                unused as of 4553e1d8
HAVE_STRUCT_SOCKADDR_UN  unused as of b4cea00a
HAVE_SYSCONF             unused as of f83356c7
TM_IN_SYS_TIME           never used, obsolescent per Autoconf documentation