updated cargo config

[Tomer-Eliahu]

Follow up to #17: updating the rest of the cargo configs in the book.

I think @BartMassey is probably right that this fix is needed due to platform differences (I am on Windows and without this I get an error). If this change causes an error for anyone else maybe it is best to just mention this as a potential fix in the General troubleshooting section of the book.

[neduard]

Hey - just letting you know this doesn't work on my system - I've had issues with flashing 03-setup getting the following error (introduced in the related PR #17):

> cargo embed
   Compiling rtt-check v0.1.0 (/home/ed/discovery-mb2/mdbook/src/03-setup)
error: could not compile `rtt-check` (bin "rtt-check") due to 1 previous error
error: linking with `rust-lld` failed: exit status: 1
  |
  = note: LC_ALL="C" PATH="/home/ed/.rustup/toolchains/stable-x86_64-unknown-linux-musl/lib/rustlib/x86_64-unknown-linux-musl/bin:/home/ed/.cargo/bin:/home/ed/.local/bin:/home/ed/.cargo/bin:/home/ed/.local/bin:/usr/local/sbin:/usr/local/bin:/usr/bin:/usr/sbin:/sbin:/bin" VSLANG="1033" "rust-lld" "-flavor" "gnu" "/tmp/rustc4X4LcF/symbols.o" "<3 object files omitted>" "--as-needed" "-Bstatic" "/home/ed/discovery-mb2/target/thumbv7em-none-eabihf/debug/deps/{libcortex_m_rt-10d5562cd3ae9879.rlib,libnrf52833_pac-2de8fc1100e222c7.rlib,libpanic_rtt_target-3ea4e2eabdd9713f.rlib,librtt_target-4d15bfbf65248f0c.rlib,libufmt_write-aafa603ef3be7e22.rlib,libcortex_m-e66cc1941f71678e.rlib,libembedded_hal-26f46a1f292fb026.rlib,libvoid-38e58dbcdcbca52a.rlib,libnb-7cd497236ce83849.rlib,libnb-4badc18e08ab03a2.rlib,libcritical_section-9b1e1eff12d07eb4.rlib,libvolatile_register-6439588298711bd7.rlib,libvcell-5fe821c2679c6c8e.rlib,libbare_metal-99ad248edd9d3415.rlib}" "/home/ed/.rustup/toolchains/stable-x86_64-unknown-linux-musl/lib/rustlib/thumbv7em-none-eabihf/lib/{librustc_std_workspace_core-89717189c5caa977.rlib,libcore-e6122f30404945e0.rlib,libcompiler_builtins-5581ff22e90261f7.rlib}" "-Bdynamic" "--eh-frame-hdr" "-z" "noexecstack" "-L" "/home/ed/discovery-mb2/target/thumbv7em-none-eabihf/debug/build/rtt-check-7d4ade2b6103c7d0/out" "-L" "/home/ed/discovery-mb2/target/thumbv7em-none-eabihf/debug/build/cortex-m-4af511cf6e414211/out" "-L" "/home/ed/discovery-mb2/target/thumbv7em-none-eabihf/debug/build/cortex-m-rt-b3105827ac0d8c50/out" "-o" "/home/ed/discovery-mb2/target/thumbv7em-none-eabihf/debug/deps/rtt_check-50c3fc1d83ac45bd" "--gc-sections" "-Tlink.x" "-Tlink.x"
  = note: some arguments are omitted. use `--verbose` to show all linker arguments
  = note: rust-lld: error: /home/ed/discovery-mb2/target/thumbv7em-none-eabihf/debug/build/rtt-check-7d4ade2b6103c7d0/out/memory.x:5: region 'FLASH' already defined
          >>>   FLASH : ORIGIN = 0x00000000, LENGTH = 512K
          >>>                                         ^
          

       Error Failed to run cargo build: exit code = Some(101).
             
             Stack backtrace:
                0: anyhow::error::<impl core::convert::From<E> for anyhow::Error>::from
                1: probe_rs::cmd::cargo_embed::main_try
                2: probe_rs::main
                3: std::sys::backtrace::__rust_begin_short_backtrace
                4: std::rt::lang_start::{{closure}}
                5: std::rt::lang_start_internal
                6: main

note the duplicated argument "-Tlink.x". This has been reported by others (link1, link2). Indeed with this patch, I get the error on 05-meet-your-software as well.

It's strange since we already have a top level .cargo/config.toml. Not very familiar with cargo & cargo embed, but it seems to pick it up even if I remove the example-specific .cargo folders. Not sure what's the correct approach.

Versions:

cargo embed 0.27.0 (git commit: crates.io)
cargo 1.85.1 (d73d2caf9 2024-12-31)

[BartMassey]

@neduard Thanks much for the report. What host platform are you on? Which chapter were you trying to build? I didn't update anything after Chapter 3 because subsequent chapters have Cargo dependencies that should make it unnecessary to explicitly include link.x — but maybe so.

[Tomer-Eliahu]

As this causes an error for others, I closed this pull request.