Raw, very basic bootloader binary in pure Rust?

My goal is to do https://github.com/cfenollosa/os-tutorial/tree/master/01-bootsector-barebones in pure Rust using asm, or rather global_asm.

Here's what I tried:

1. Create a new project and create .cargo/config.toml with these contents:

   [build]
   target = "target.json"
   
   [unstable]
   build-std = ["core", "compiler_builtins"]
   

2. Create the target.json with these contents:

   {
       "llvm-target": "x86_64-unknown-none",
       "data-layout": "e-m:e-i64:64-f80:128-n8:16:32:64-S128",
       "arch": "x86_64",
       "target-endian": "little",
       "target-pointer-width": "64",
       "target-c-int-width": "32",
       "os": "none",
       "executables": true,
       "linker-flavor": "ld.lld",
       "linker": "rust-lld",
       "panic-strategy": "abort",
       "disable-redzone": true,
       "features": "-mmx,-sse,+soft-float"
   }
   

3. And finally src/main.rs:

   #![feature(global_asm)]
   #![no_main]
   #![no_std]
   
   global_asm!(r#"
   loop:
     jmp loop
   .org 510
   .word 0xaa55
   "# :::: "volatile");
   
   #[panic_handler]
   fn panic(panic_info: &core::panic::PanicInfo) -> ! {
       loop {}
   }
   

4. A few setup commands:

   rustup override set nightly
   cargo install cargo-binutils
   rustup component add llvm-tools-preview
   

5. Compile and transform it using cargo objcopy -- -O binary boot_sect_simple.bin

This compiles successfully and the next step would be to run the binary in QEMU. The problem is that this boot_sect_simple.bin contains zero bytes.

How can I get this to work?