I'm writing a bootloader for cortex-m4 and I think I want something like this:

    let x = addr;
    unsafe{
        asm!(
            "ldr {tmp}, [{x}, #4]",
            "ldr sp, [{x}]",
            "blx {tmp}",
            x = in(reg) x,
            tmp = out(reg) _,
            options(noreturn),
        );
    }

However that is not possible:

error: asm outputs are not allowed with the `noreturn` option
  --> src/main.rs:19:13
   |
19 |             tmp = out(reg) _,
   |             ^^^^^^^^^^^^^^^^

error: could not compile `bootloader` (bin "bootloader") due to 1 previous error

What would be the correct way to do this?

My current workaround is to add core::hint::unreachable_unchecked() after the asm block. Is that reasonable?

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