Zig extern struct recognized differently from Zig and C

build.zig

const Builder = @import("std").build.Builder;

pub fn build(b: *Builder) void {
    const exe = b.addExecutable("test", "main.zig");
    exe.addIncludeDir(".");
    exe.linkSystemLibrary("c");

    exe.setTarget(b.standardTargetOptions(.{}));
    exe.setBuildMode(b.standardReleaseOptions());
    exe.install();
}

main.zig

const makeFoo = @import("shared.zig").makeFoo;
const useFoo = @cImport(@cInclude("middle.h")).useFoo;

pub fn main() void {
    useFoo(makeFoo());
}

middle.h

#ifndef MIDDLE_H
#define MIDDLE_H

#include "shared.h"

void useFoo(struct Foo foo) { }

#endif // MIDDLE_H

shared.h

#ifndef SHARED_H
#define SHARED_H

#include <stdint.h>

struct Foo {
    float bar;
    int16_t baz;
};

struct Foo makeFoo(void);

#endif // SHARED_H

shared.zig

const Foo = extern struct {
    bar: f32 = 4.20,
    baz: i16 = 69,
};

pub export fn makeFoo() Foo {
    return Foo{};
}