Struct with non-POD fields can be improperly constructed from Rust

[dtolnay]

// src/input.h

#pragma once
#include <string>
struct T {
  std::string s;
};
void f(const T& t);

// src/input.cc

#include "input.h"
#include <iostream>

void f(const T& t) {
  std::cout << t.s << std::endl;
}

// src/main.rs

use autocxx::include_cxx;

include_cxx!(Header("input.h"), Allow("T"), Allow("f"));

fn main() {
    ffi::cxxbridge::f(&ffi::cxxbridge::T {});
}

$  cargo run
Segmentation fault (core dumped)

[adetaylor]

Hmmm. Yep. That's going to be tougher to figure out.

[adetaylor]

I'd love to think that this will be as simple as putting in a private field, but I have a feeling this one is going to be more icky.