[pcwalton]

I've thought about switching to only one input value for Rust, but it's needed for the FFI, so once we're paying the complexity there we might as well pay it everywhere. Besides, it'll make it easier to add optional and named parameters if we ever do in the future.

[taliesinb]

Wouldn't memory layout on the stack be the same for a tuple vs a sequence of arguments?

[pcwalton]

Unfortunately calling conventions are hideously complex; some arguments go in registers, some go on the stack, some change depending on whether they're structs or floats or not…it's a giant mess :(