undefined reference to `core::panicking::panic'

[kpreid]

I'm trying to use crank and crankstart as directed in the READMEs. However, building for the device fails (while the simulator succeeds):

$ crank build --device
   Compiling compiler_builtins v0.1.100
...
/usr/local/playdate/gcc-arm-none-eabi-9-2019-q4-major/bin/../lib/gcc/arm-none-eabi/9.2.1/../../../../arm-none-eabi/bin/ld: <path …>: in function `compiler_builtins::mem::impls::copy_forward::copy_forward_misaligned_words':
/<path…>/compiler_builtins-0.1.100/src/mem/impls.rs:76: undefined reference to `core::panicking::panic'
collect2: error: ld returned 1 exit status

I'm currently trying to just compile my own copy-and-paste of the hello_world example. Does this indicate something I need to fix, or configure, or is it a bug in the tool?

The only previous mention I saw of this error is pd-rs/crank#42 (comment).

• OS: macOS
• Playdate SDK: 2.0.3
• crank: crankstart-cli v0.2.9 (rev = 155da63746a1408f6cdd2e120bee64c52871c58b)

[boozook]

Hey @kpreid 👋
Is there rust-src rustup component installed?

[kpreid]

Yes:

$ rustup +nightly component add rust-src
info: component 'rust-src' is up to date

[boozook]

I can't reproduce unfortunately.
But I have an idea that can help me determine what's going wrong.

Could you try run on device any example in that project?

Just because I know differences between two projects ;)

[parasyte]

I see that as well for debug builds. But it builds fine with release mode.

$ crank build --device --release

Now that I got my hardware back from RMA, this is the first time I've tried my Rust project on it. And it boots to a pure white screen. That's disappointing.

The sprite_game example works correctly on the hardware, though! So, this white screen thing is my own bug.

[kpreid]

Ah, the build or run worked with --release. I guess that makes this a bug with a workaround.

[boozook]

Now that I got my hardware back from RMA, this is the first time I've tried my Rust project on it.

I'm glad to hear that, congrats!
And thanks for help. I didn't recognise that 🤦🏻‍♂️

[parasyte]

I guess that makes this a bug with a workaround.

Yep! I would like to see the bug fixed as well. So, uh, I did it: pd-rs/crank#52

[boozook]

Great! Merged. ❤️‍🔥
I have to say that cargo-playdate supports debug builds as well as probably any custom profile ;)

[boozook]

Summon @adamsoutar, @parasyte,
Do you have ideas for this?