/*
	 * Each pass through this loop adds up to one more OpNode. Allocate
	 * space for one if required.
	 */

	if (nodesUsed >= nodesAvailable) {
	    int size = nodesUsed * 2;
	    OpNode *newPtr = NULL;

	    do {
	      if (size <= UINT_MAX/sizeof(OpNode)) {
		newPtr = attemptckrealloc(nodes, size * sizeof(OpNode));
	      }
	    } while ((newPtr == NULL)
		    && ((size -= (size - nodesUsed) / 2) > nodesUsed));
	    if (newPtr == NULL) {
		TclNewLiteralStringObj(msg,
			"not enough memory to parse expression");
		errCode = "NOMEM";
		goto error;