build.rs

extern crate gcc;

fn main() {
    gcc::compile_library("libhello.a", &["src/test.c"]);
}

Cargo.toml

[package]
name = "test"
version = "0.0.1"
authors = ["Pierre Krieger <pierre.krieger1708@gmail.com>"]
build = "build.rs"

[dependencies]
libc = "*"

[build-dependencies]
gcc = "*"

main.rs

extern crate libc;

use std::ptr;

#[repr(C)]
pub struct Foo {
    pub a: libc::size_t,
    pub b: libc::size_t,
    pub c: libc::size_t,
    pub d: libc::size_t,
}

extern {
    // this version works with MinGW and crashes with MSVC:
    fn foo(_: *const libc::c_void, _: *const libc::c_void, _: *const libc::c_void,
           _: *const libc::c_void, _: Foo) -> libc::size_t;
           
    // this version works with MSVC and crashes with MinGW
    //fn foo(_: *const libc::c_void, _: *const libc::c_void, _: *const libc::c_void,
    //       _: *const libc::c_void, _: *const Foo) -> libc::size_t;
}

fn main() {
    let f = Foo { a: 1, b: 2, c: 3, d: 4 };
    
    // works with MinGW only:
    let ret = unsafe { foo(ptr::null(), ptr::null(), ptr::null(), ptr::null(), f) };

    // works with MSVC only:
    //let ret = unsafe { foo(ptr::null(), ptr::null(), ptr::null(), ptr::null(), &f) };

    println!("obtained {:?}", ret);
}

test.c

#include <stdio.h>

typedef struct {
    size_t a;
    size_t b;
    size_t c;
    size_t d;
} Foo;

size_t foo(void* a, void* b, void* c, void* d, Foo f) {
    return f.c;
}