error[E0463]: can't find crate for `core` note: the `thumbv7m-none-eabi` target may not be installed

Question

I'm trying to blink the led on a bluepill (arm STM32) and followed the instructions from this tutorial, but i run into this error when i try to compile the code. i use ubuntu.

i just installed rust / cargo as figured in the tutorial. i have stlink installed, i have no experience with rust, cargo or bluepil.

$ cargo build --release:

        error[E0463]: can't find crate for `core`
      |
      = note: the `thumbv7m-none-eabi` target may not be installed

does it depend on the ./cargo/config file?

$ rustup show
Default host: x86_64-unknown-linux-gnu
rustup home:  /home/marco/snap/rustup/common/rustup

installed toolchains
--------------------

stable-x86_64-unknown-linux-gnu (default)
nightly-x86_64-unknown-linux-gnu

installed targets for active toolchain
--------------------------------------

thumbv7m-none-eabi
x86_64-unknown-linux-gnu

active toolchain
----------------

stable-x86_64-unknown-linux-gnu (default)
rustc 1.46.0 (04488afe3 2020-08-24)

$ rustup target add thumbv7em-none-eabi
info: downloading component 'rust-std' for 'thumbv7em-none-eabi'
info: installing component 'rust-std' for 'thumbv7em-none-eabi'
info: Defaulting to 500.0 MiB unpack ram

$ cargo build --release
   Compiling semver-parser v0.7.0
   Compiling typenum v1.12.0
   Compiling proc-macro2 v1.0.19
   Compiling unicode-xid v0.2.1
   Compiling syn v1.0.39
   Compiling stable_deref_trait v1.2.0
error[E0463]: can't find crate for `core`
  |
  = note: the `thumbv7m-none-eabi` target may not be installed

Does it depend on the name in the "Cargo.toml" file? What am i doing wrong?

Answer 1

export PATH="$HOME/.cargo/bin:$PATH"