} else {
        // See if any resource type is used.
        bool resource = false;
        std::function<bool(mlir::Type)> record_resource;
        record_resource = [&](mlir::Type type) {
          type.walk([&](mlir::Type t) {
            if (resource) return mlir::WalkResult::interrupt();
            if (mlir::isa<mlir::TF::ResourceType>(type)) {
              resource = true;

	// on an OS stack, we must keep a reference to mp alive so that the GC
	// doesn't free mp while we are still using it.
	//
	// Note that the free list must not be linked through alllink because
	// some functions walk allm without locking, so may be using alllink.
	//
	// N.B. It's important that the M appears on the free list simultaneously
	// with it being removed so that the tracer can find it.
	mp.freeWait.Store(freeMWait)

and arise from denser Substances than those of Vapours, thence it is that true Air is more ponderous than Vapour, and that a moist Atmosphere is lighter than a dry one, quantity for quantity. From the same repelling Power it seems to be that Flies walk upon the Water without wetting their Feet; and that the Object-glasses of long Telescopes lie upon one another without touching; and that dry Powders are difficultly made to touch one another so as to stick together, unless by melting them, or wetting...