Hello
Apparently the RTOS you are using is expected symbols __SP_END and __STACK_SIZE to be defined.
In order to be able to link the application you have to define them.
Usually you define these symbols in the linker command file.
For example:
__STACK_SIZE = 0x800;
__SP_END = 0x20008000 - __STACK_SIZE;
This is directly related to the way the RTOS expects the stack to be set up.
So I would recommend you to check with your RTOS provider, how he is expecting the symbol to be defined.
CrasyCat