FreeRTOS with enabling cpp, all functions are not working
What do you mean by "doing -cpp"?
Do you just convert the project to C++ and recompile or do you make any other change in the project?
FreeRTOS source code is C code and should always be compiled as C code, not as C++ code, so do not rename any .c file as .cpp, except perhaps for the main.c and, of course, your own source code.
Hope this helps,
Bernard (Ac6)