Link with lld, update cortex-m-rt to use new procedural macros

.cargo/config

@@ -1,13 +1,10 @@
 [target.thumbv7em-none-eabihf]
 runner = 'arm-none-eabi-gdb'
 rustflags = [
-  "-C", "link-arg=-Wl,-Tlink.x",
-  "-C", "link-arg=-nostartfiles",
-
-  # uncomment to use rustc LLD to link programs (a)
-  # "-C", "link-arg=-Tlink.x",
-  # "-C", "linker=lld",
-  # "-Z", "linker-flavor=ld.lld",
+    # link with lld
+    "-C", "link-arg=-Tlink.x",
+    "-C", "linker=rust-lld",
+    "-Z", "linker-flavor=ld.lld",
 ]
 
 [build]

Cargo.toml

@@ -4,23 +4,23 @@ version = "0.0.1"
 authors = ["jonlamb-gh <lamb.jon.io@gmail.com>"]
 
 [dependencies.panic-abort]
-version = "0.2.0"
+version = "0.3.0"
 optional = true
 
 [dependencies.panic-semihosting]
-version = "0.3.0"
+version = "0.4.0"
 optional = true
 
 [dependencies.cortex-m-semihosting]
-version = "0.3.0"
+version = "0.3.1"
 optional = true
 
 [dependencies.cortex-m]
-version = "0.5.4"
+version = "0.5.7"
 features = ["const-fn"]
 
 [dependencies.cortex-m-rt]
-version = "0.5.2"
+version = "0.6.1"
 features = ["device"]
 
 [dependencies.nucleo-f767zi]

README.md

@@ -11,12 +11,6 @@ cargo install --force rustfmt-nightly
 rustup target add thumbv7em-none-eabihf
 
 cargo install svd2rust
-
-# currently used for linking
-# TODO - switch over to lld
-sudo add-apt-repository ppa:team-gcc-arm-embedded/ppa
-sudo apt update
-sudo apt install gcc-arm-embedded
 ```
 
 ```bash
@@ -25,6 +19,8 @@ cargo build
 
 ## Deploying
 
+Install [stlink](https://github.com/texane/stlink) tools.
+
 ```bash
 ./scripts/deploy
 
@@ -39,6 +35,12 @@ st-flash --format ihex write target/thumbv7em-none-eabihf/debug/oxcc.hex
 
 ## Debugging
 
+Install OpenOCD:
+
+```bash
+sudo apt-get install openocd
+```
+
 ```bash
 ./scripts/run-openocd