askrodney[m]: Hi, I'm running through the discovery micro:bit book.  I am getting an unexpected SIGINT on [Chapter 5.3](https://docs.rust-embedded.org/discovery/microbit/05-led-roulette/debug-it.html), when I try to debug.  I am running an Intel Mac with micro:bit v2, and earlier test (from the book) runs fine for me.

I run 

```shell
cargo embed --features v2 --target thumbv7em-none-eabihf
```

Then in new tab:

```
gdb target/thumbv7em-none-eabihf/debug/led-roulette

(gdb) target remote :1337
(gdb) break main
(gdb) continue
(gdb) layout src
(gdb) break 13
```
This sets the breakpoint at line 16, not 13 (as the book example does), and my code lines and layout (in my TUI) match the book's. Instead I set 

```
(gdb) break 12
```
which sets breakpoint at 12. Then, when I run

```
(gdb) continue
```

I get:

```shell
Program received signal SIGNIT, Interrupt.
led_roulette::__cortex_m_rt_main () at src/main.rs:10
sw_vers -productVersion
13.6
```

I expected to get feedback, that the debugger continued to line 12, and stopped (and not the SIGINT).

I flash with:
cargo embed --features v2 --target thumbv7em-none-eabihf


And source is:

```rust
#![deny(unsafe_code)]
#![no_main]
#![no_std]

use cortex_m_rt::entry;
use microbit as _;
use panic_halt as _;

#[entry]
fn main() -> ! {
    let _y;
    let x = 42;
    _y = x;

    // infinite loop; just so we don't leave this stack frame
    loop {}
}
```

Complete project code is at [https://github.com/rust-embedded/discovery/microbit/src/05-led-roulette](https://github.com/rust-embedded/discovery/tree/master/microbit/src/05-led-roulette)

There is an [open issue on the discovery repo](https://github.com/rust-embedded/discovery/issues/517), which describes the same problem, and alludes to the possibility of this being related to changes in micro:bit v2.20 vs. v2.0.


I have a v2.21 micro:bit
GNU gdb (GDB) 13.2
rustc 1.73.0-beta.9 (2ce543cc5 2023-09-29)


Can anyone give me some pointers on progressing?