programs are not halted at launch

[jmayclin]

I'm following chapter 5, and programs are not halted when launched.

When I open GDB (gdb-multiarch) after running cargo, embed, I see the following

Reading symbols from ../../../target/thumbv7em-none-eabihf/debug/examples/light-it-up...
(gdb) target remote :1337
Remote debugging using :1337
light_it_up::__cortex_m_rt_main ()
    at mdbook/src/05-meet-your-software/examples/light-it-up.rs:17
17          loop {}
(gdb) 

Indicating that the program has already run.

My cargo-embed version is

cargo embed 0.27.0 (git commit: 7d59a31)

I apologize for the sparsity of the issue, but I have very little experience with embedded development and am not quite sure how to help debug this.

[BartMassey]

Thanks for checking in! Sorry you're having an issue.

Forgive me for starting with the easy thing… did you compile with --release? It's easy to do, and if you did you'd probably see something like this.

I'm kind of swamped right now, but I'll try to reproduce your problem in the next day or two and we'll see what we can figure out.

[neduard]

Hey! I just came across this also & had a look. I think the issue might be from here?

• since rtt.enabled is false, we do else if should_resume_core(&config)
• however, looking at the definition of should_resume_core we find if config.flashing.enabled { true }
• since flashing is enabled by default, it would indicate that the core is resumed regardless of the halt_afterwards flag?

This was introduced in v0.25. Fortunately, the old (& recommended by the book) version works and can be installed with cargo install 'probe-rs-tools@^0.24' --locked.

[BartMassey]

@neduard Thanks very much for this! Could you file an issue for us? It's all a bit twitchy since apparently 0.24 depends on several since-yanked crates.

[sax]

I've been experiencing this and a number of other differences. For most of the cases (at least up to section 7.2), I've found that I can set breakpoints and then run monitor reset halt in gdb to reset to the expected state in the book.

[BartMassey]

@sax Please check the Embed.toml settings and work with cargo embed: whether the program halts at startup is a function of that. If you are still having troubles let me know and I'll try to reproduce.

[Igonato]

monitor reset halt did the job for me 👍

---

Please check the Embed.toml settings and work with cargo embed: whether the program halts at startup is a function of that. If you are still having troubles let me know and I'll try to reproduce.

@BartMassey, what specifically should be checked in the file? I'm seeing the issue with the most recent version from the repo (1621aab5ed)

[BartMassey]

See #27. probe-rs was borked, and a fix will be delivered soon.