Earlier quoted context omitted.
Sure. malloc'ed item could be the same as malloc_gc'd, but with its reference count artificially bumped up by 1. free() would decrement the count and the item will be picked up by the GC later on. If there's a provision for an immediate disposal of unreferenced items, then we are back to the standard malloc/free behaviour in case when malloc and malloc_gc items are not mixed.
Reference counting is a bad C++ substitute for a real GC.
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