> but if there are no normal returns involved, nothing on the stack will ever be deallocated, and your program is effectively just one giant memory leak.

This is true, but there is the glorious exception which is "Cheney on the MTA": http://www.pipeline.com/~hbaker1/CheneyMTA.html [https://news.ycombinator.com/item?id=7417906]

This describes a way of implementing a scheme->C compiler using CPS which allows the C functions to never return, and doesn't blow the stack. When the stack gets big enough, you do a garbage collection run, copying live data to a new stack. Then, you reset the stack pointer using a judiciously chosen argument to alloca().