Using STM32Cube_FW_F4_V1.9.0 and setup a project with CubeMX 4.11 and using Freertos.
I usually build with -Wundef. When compiling cmsis_os.c, I earn a:
core_cmFunc.h:501:12: warning: "__CORTEX_M" is not defined -Wundef
This is, because `#include "core_cmFunc.h"` obvouisly needs a e.g. `#include …` before so that the preprocessor symbol `__CORTEX_M` became defined. This appears for every source which tries to include cmsis_os.h (e.g. the cubemx generated freertos.c).