1 #include <stdio.h> 2 3 __attribute__((noinline)) void big(void) 4 { 5 /* The below ensures the stack grows a lot. However, we hope the stack 6 extension is not done yet, as no memory has been read/written. */ 7 volatile char c[200000]; 8 9 /* Access only the higher part of the stack, to avoid mapping SP */ 10 /* The below 2 printfs should produce deterministic output, whatever 11 the random value of c[]. */ 12 if (c[200000 - 1]) 13 fprintf(stderr, "Accessing fresh %s\n", "stack"); 14 else 15 fprintf(stderr, "Accessing %s stack\n", "fresh"); 16 17 } 18 19 int main(void ) 20 { 21 big(); 22 return 0; 23 } 24
