Attempt at using zig's export to C feature

thing.h

#ifndef THING_H
#define THING_H

#include <stdint.h>

#ifdef __cplusplus
#define THING_EXTERN_C extern "C"
#else
#define THING_EXTERN_C
#endif

#if defined(_WIN32)
#define THING_EXPORT THING_EXTERN_C __declspec(dllimport)
#else
#define THING_EXPORT THING_EXTERN_C __attribute__((visibility ("default")))
#endif

struct Node;
struct makeThing(u32);
THING_EXPORT void Init(struct makeThing(u32) * ptr, uint32_t x);

#endif

thing.zig

// Attempt at using zig's export to C feature
// Compile with `zig build-lib --output-h thing.h thing.zig`

const std = @import("std");

const List = std.LinkedList(void);

fn makeThing(comptime member:type) type {
    return struct {
        const Self = @This();

        // intrusive LinkedList
        node: List.Node,

        /// initialize Thing structure
        pub fn init(x:member) Self {
            return Self {
                .node = List.Node.init(undefined),
                .x = x,
            };
        }

        x: member,

        pub fn get() member {
            return x;
        }
    };
}

const u32Thing = makeThing(u32);

export fn InitializeThing(ptr: *u32Thing, x:u32) void {
    ptr.* = u32Thing.init(x);
}