O_BACK            169 regex/debug.c  		case O_BACK:
O_BACK            288 regex/engine.c 		case O_BACK:
O_BACK            538 regex/engine.c 		while (m->g->strip[ss] != SOP(O_BACK, i))
O_BACK            865 regex/engine.c 		case O_BACK:
O_BACK            512 regex/regcomp.c 			EMIT(O_BACK, i);