Cannot find linker script memory.x

[albertskog]

Hi! I'm trying out this template on a Bluepill board with STM32F103C8 and stm32f1xx-hal. After following the setup steps (and working around #18) I get a linker error about missing memory.x when running cargo rb hello.

Copying memory.x from the HAL's repository into the root of the project as suggested by their readme solves the problem.
https://github.com/stm32-rs/stm32f1xx-hal/blob/master/memory.x

Is this expected to be part of step 5 ("5. Import your HAL")? I could make a PR on the readme but I'm not sure if this works differently for other HAL's?

[japaric]

Some HAL crates provide a memory.x file (the nrf HALs do) but some don't. I think most HAL crates don't consistently document whether they provide a memory.x or not (the nrf HALs don't document that they provide a memory.x; the stm32f1xx-hal does document that a memory.x file is required).

In terms of this template documentation, we should mention that when using a HAL additional steps maybe required, like writing a memory.x file, and that the HAL documentation should be checked. We could also write a troubleshooting section and mention that "memory.x not found" is a common error and how to fix it (write a memory.x file).

Semi-orthogonal to this, it may be possible to generate the memory.x file using probe-rs and the --chip information passed to probe-run. Whether that functionality should be in probe-run or a different tool (an embedded version of cargo-generate?) I do not know.

[albertskog]

👍 I made a PR on the readme ⬆️

Regarding alternative methods - assuming a HAL has a memory.x, maybe it would be possible to use it "in place", without copying it into the project? I was thinking similar to how Cargo looks in several places for config.toml (https://doc.rust-lang.org/cargo/reference/config.html)

Edit: there is an open issue about ways to handle this in Cargo: rust-lang/cargo#7984