RB_HEAD
#define RB_HEAD(name, type) \
RB_HEAD(penalties_by_addr, penalty) penalties_by_addr4, penalties_by_addr6;
static RB_HEAD(nl_data_t, nl_data) rpcnl_clients;
static RB_HEAD(upsock_t, upsock) upcall_sockets;
#define RB_HEAD(name, type) \
static RB_HEAD(tree, node) root;
static RB_HEAD(cmap_sym, charmap) cmap_sym;
static RB_HEAD(ctypes, ctype_node) ctypes;
static RB_HEAD(mmio_rb_tree, mmio_rb_range) mmio_rb_root, mmio_rb_fallback;