odin vulkan fails at instance creation ^cstring at fault

package main

import glfw "shared:odin-glfw"
import fmt "core:fmt"
import vk "shared:odin-vulkan"

main :: proc() {
    window := init_window(500, 500, "hi");

    fmt.println("start");

    instance := create_instance();
    defer vk.destroy_instance(instance, nil);

    fmt.println("end");

    for !glfw.window_should_close(window) {
        glfw.poll_events();
    }
}

init_window :: proc(width, height: int, title: string) -> glfw.Window_Handle {
    error_callback :: proc"c"(error: i32, desc: cstring) {
        fmt.printf("Error code %d: %s\n", error, desc);
    }

    glfw.set_error_callback(error_callback);

    glfw.init();

    glfw.window_hint(glfw.CLIENT_API, cast(int) glfw.NO_API);
    glfw.window_hint(glfw.RESIZABLE, cast(int) glfw.FALSE);

    window := glfw.create_window(width, height, title, nil, nil);
    if window == nil do panic("window couldnt be created");

    return window;
}

// c macro to check the result of a create call
VK_CHECK :: proc(call: vk.Result) {
    assert(call == vk.Result.Success);
}

// c macro to create a vulkan api version
vk_make_version :: proc(major, minor, patch: u32) -> u32 {
    return (((major) << 22) | ((minor) << 12) | (patch));
}

debug_layers := [1]cstring {
    "VK_LAYER_LUNARG_standard_validation",
};

create_instance :: proc() -> vk.Instance {
    using vk;

    app_info: ApplicationInfo;
    app_info.sType = StructureType.ApplicationInfo;
    app_info.apiVersion = API_VERSION_1_1;

    create_info: InstanceCreateInfo;
    create_info.sType = StructureType.InstanceCreateInfo;
    create_info.pApplicationInfo = &app_info;

    // without these we can normally compile
    create_info.ppEnabledLayerNames = &debug_layers[0];
    create_info.enabledLayerCount = len(debug_layers);

    instance: vk.Instance;
    VK_CHECK(vk.create_instance(&create_info, nil, &instance));

    return instance;
}