How to allocate structs on the heap without taking up space on the stack in stable Rust?

Question

In this code...

struct Test { a: i32, b: i64 }
    
fn foo() -> Box {              // Stack frame:
            


        

Answer 1

Is there a way to allocate directly to the heap without box?

No. If there was, it wouldn't need a language change.

People tend to avoid this by using the unstable syntax indirectly, such as by using one of the standard containers which, in turn, uses it internally.

See also:

• How to allocate arrays on the heap in Rust 1.0?
• Is there any way to allocate a standard Rust array directly on the heap, skipping the stack entirely?
• What does the box keyword do?
• What is the <- symbol in Rust?