Where is __main?

return 0 should never execute. We should never get to return 0 statement.
I assume you want to say that the code should never exit main(). True.
But when using RTOS, main() is terminated.
And, "return" in main() is not good for embedded designs.

Coming back to the topic
what is your startup code?
possibly post your code.
And use Tips for Posting Messages

return 0 should never execute. We should never get to return 0 statement.
I assume you want to say that the code should never exit main(). True.
But when using RTOS, main() is terminated.
And, "return" in main() is not good for embedded designs.

Coming back to the topic
what is your startup code?
possibly post your code.
And use Tips for Posting Messages

But when using RTOS, main() is terminated.

Really?

Correct me if i am wrong

The os_sys_init(MasterTask) is called before termination.
Hence it is valid if the while(1) statement is not written at the end of main(), because the controller executes "os_idle_demon()" even if there are no other tasks. And other tasks, if present, also have code written in infinite loop. Hence the controller will always have atleast one infinite loop.

int main(void)
{
    .
    .
    .


    os_sys_init(MasterTask);

    //while(1);     //
}

Currently, I'm not working on this project. If I resume this project, I'll continue the thread.

Thank you so much for valuable feedback.

We downgraded to Keil uVision4 version 4.54 and I'm still unable to hit my main().

I am stuck in Keil's code as follows:

Filename RT_Agent.c

void _sys_exit (int return_code) {
  /* Endless loop. */
  while (1);
}

And idea why I'm stuck in this while(1).