Development tools for Zephyr on STM32Workbench for Zephyr: VS Code extension to set up, build, flash and debug Zephyr applications on STM32.Devicetree manager: browse, edit and visualize Zephyr devicetree, STM32CubeMX-like for Zephyr.
Yes, I'm aware of it. Unfortunately, there are many un-documented features in gcc.
In fact, I'm looking for compatibility list between GNU ARM gcc and official ARM compiler (e.g. armcc).