ALT_STACK_CHECK

Hi,

In crt0.S file ,you can find that

#ifdef ALT_STACK_CHECK

mov et, zero# endif

I have enabled the "Run time stack checking" option in system library project, but I can't find the definition of ALT_STACK_CHECK in any file.

Anyone help me that where can I fine the definition of ALT_STACK_CHECK?

Thanks in advance,

David