1 error[E0463]: can't find crate for `core`
3 = note: the `thumbv7em-none-eabihf` target may not be installed
4 = help: consider downloading the target with `rustup target add thumbv7em-none-eabihf`
5 = help: consider building the standard library from source with `cargo build -Zbuild-std`
7 error[E0463]: can't find crate for `compiler_builtins`
9 error[E0463]: can't find crate for `cortex_m`
10 --> $DIR/compiler-builtins-error.rs:10:1
12 LL | extern crate cortex_m;
13 | ^^^^^^^^^^^^^^^^^^^^^^ can't find crate
15 error: requires `sized` lang_item
17 error: aborting due to 4 previous errors
19 For more information about this error, try `rustc --explain E0463`.