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A comment on Zero-cost futures in Rust. Parent comment

Re:Zero-cost futures in Rust by pcwalton on Thursday August 11, 2016 @06:01PM (#12271918)
You don't have to destroy the "stack frame" (by which I assume you mean the state retained between blocking operations) every time you enter and leave. Why do you think you need to?
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Re:Zero-cost futures in Rust by saynsedit on Thursday August 11, 2016 @07:34PM (#12272469)
He's talking about the difference between swapping the stack pointer and executing a single "jump" instruction vs initiating a full function call (pushing argument(s), function prologue/epilogue)
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Re:Zero-cost futures in Rust by pcwalton on Thursday August 11, 2016 @08:22PM (#12272711)
Calling a function isn't "allocation". And you don't just swap the stack pointer: you have to reload the register state. It's the same cost as a function call.
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