Compilation fails using char*

[bluesilenceln]

Describe the bug
error[E0599]: no function or associated item named new found for struct root::A in the current scope

To Reproduce

typedef struct A {
    char * b;
}A;

use autocxx::prelude::*;

include_cpp! {
    #include "declare.h"
    safety!(unsafe_ffi)
    generate!("A")
}

fn main() {
    let a = ffi::A::new();
}

[adetaylor]

Please could you raise a PR containing a failing test per these instructions