/* Macros for aggregating results built on the stack into an array,
* while maintaining a bound on stack consumption. Use like this:
*
* check_stack(120);
* BEGIN_AGGREGATE_ARRAY(estimated_size_of_final_array) {
* for (...) {
* ... stuff that produces a value on the stack ...
* DO_AGGREGATE_ARRAY(120);
* ...
* }
* } END_AGGREGATE_ARRAY;
*
* The array is left on top of the stack.
*/