This is a small, and somewhat experimental, example of how to cross compile for an Arm Cortex-M4 MCU using Bazel and the IAR C/C++ compiler toolchain.

The example uses the STM32F429II MCU as target and is intended to be portable to other targets without too much effort.

• generic IAR toolchain config is in toolchains/iar
• toolchain flags for build configs in .bazelrc
• target specific flags in /platforms (todo )
• configurations for debug and release specified in .bazelrc

Tested with Bazel v8 LTS using WORKSPACE GitHub actions workflow builds the release configuration of the project.

Known issues

• linker map file is not generated

Todo

• possibly move from WORKSPACE to Bzlmod
• add cstartup
• update IAR toolchain to 9.70.4
• add more complete GitHub action workflow
• move target specific build flags to platforms (?)