Pure Rust Start-Up Code w/o Pointer Provenance issues?

startup.rs

#[no_mangle]
pub unsafe extern "C" fn ResetHandler() -> ! {
    run();
    loop {}
}

pub unsafe fn run() {
    extern "C" {
        static mut _sbss: u32;
        static mut _ebss: u32;

        static mut _sdata: u32;
        static mut _edata: u32;

        static _sidata: u32;
    }

    let sbss = &_sbss as *const _ as usize;
    let ebss = &_ebss as *const _ as usize;
    let bss_size = (ebss - sbss) / mem::size_of::<u32>();
    let bss = slice::from_raw_parts_mut(&mut _sbss as *mut u32, bss_size);

    for i in bss {
        *i = 0;
    }

    let sdata = &_sdata as *const _ as usize;
    let edata = &_edata as *const _ as usize;
    let data_size = (edata - sdata) / mem::size_of::<u32>();
    let data = slice::from_raw_parts_mut(&mut _sdata as *mut u32, data_size);
    let idata = slice::from_raw_parts(&_sidata as *const u32, data_size);

    data.copy_from_slice(idata);

    main()
}

pub fn main() {
    loop {}
}