STM32WB05KZ Build FLASH overflow

Dadigno · ‎2025-11-28

Hi Community,

I'm trying to build the BLE_TransparentMode example for the NUCLEO-WB05KZ, but I'm getting the following build error:

region 'FLASH' overflowed by 93348 bytes

Steps to reproduce:

Open the BLE_TransparentMode example from the MX Example Selector for NUCLEO_WB05KZ.
Change the toolchain to CMake with GCC compiler.
Open the project and configure it using the STM32 VS Code extension.
Build the project → the error appears.

Environment:

STM32CubeMX: v6.16

STM32CubeIDE for VS Code: v3.6.4

Has anyone encountered this issue or knows what might be causing the FLASH overflow with the CMake/GCC configuration?
Thanks!

Andrew Neil · ‎2025-11-28

@Dadigno wrote:
Open the BLE_TransparentMode example from the MX Example Selector for NUCLEO_WB05KZ.
Change the toolchain to CMake with GCC compiler.

Are you sure that the optimisation level is the same in your modified project?

What happens if you build the example as-is - without any modifications ?

A complex system that works is invariably found to have evolved from a simple system that worked.
A complex system designed from scratch never works and cannot be patched up to make it work.