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ARM Compiler ARM C and C++ Libraries and Floating-Point Support User Guide : Entering and exiting programs linked with microlib

Entering and exiting programs linked with microlib

Microlib requires a main() function that takes no arguments and never returns.

Use main() to begin your program. Do not declare main() to take arguments. Microlib does not support command-line arguments from an operating system.

Your program must not return from main(). This is because microlib does not contain any code to handle exit from main(). Microlib does not support programs that call exit().

You can ensure that your main() function does not return, by inserting an endless loop at the end of the function. For example:

void main()
  while (1); // endless loop to prevent return from main()