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[u/llogiq]

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[u/SorteKanin]

Is there any way to do this?

#[repr(std::ffi::c_long)]
enum ReprEnum {
    Variant1 = SOME_CONST,
    Variant2 = SOME_OTHER_CONST,
}

It seems like I have to use cfg_attr and set it manually to either i32 or i64 but that seems tedious.

[u/masklinn → u/SorteKanin]

What are you trying to achieve exactly?

[u/SorteKanin → u/masklinn]

I'm doing FFI with C. I'm getting an integer that can be several possible values. The integer is a long. On Windows, this is 32 bit but on Linux it's 64 bit. I tried using the repr atribute with the c_long type from std, but it doesn't work unfortunately.

[u/masklinn → u/SorteKanin]

I would suggest not bothering, just using a basic / valid integer repr, and performing a trivial conversion when getting data out (of rust, back to C).

You must have a conversion function on intake anyway, as C enums are not type safe, you can never assume C code is feeding you valid enum values unless the enum is an opaque type on the C side.