C abi is incomplete and incompatible with languages using non-default memory allocators. about evmjit HOT 7 CLOSED

Agreed. That was mistake.

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I'm not sure C++ cares how the struct was allocated. C++ only cares if the pointer is valid.

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This shows how you can create a struct matching C struct in Rust and pass a pointer to it to a C function.
https://doc.rust-lang.org/book/ffi.html#creating-a-safe-interface

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@debris Any comments?

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I'm not sure C++ cares how the struct was allocated. C++ only cares if the pointer is valid.

You are right. I've created a playground with a few examples and everything is working fine.*

*There is one failing test, but it is related with rust not casting ffi call argument to a reference automatically, rather than memory allocation.

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Yes, memory-is-memory. It doesn't matter where it came from when you are just using it.

Where allocations happened obviously do matter when you get to the deallocations. That is a common source of issues:

• trying to deallocate on different threads
• trying to deallocate with C++ pointers with free()
• or worse!

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Let know if you need any changes in the area.

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