gistfile1.cpp

struct foo { 
int x; 
int y; 
}; 

static struct foo f; 

/* The two following functions are running concurrently: */ 

int sum_a(void) 
{ 
int s = 0; 
int i; 
for (i = 0; i < 1000000; ++i) 
s += f.x; 
return s; 
} 

void inc_b(void) 
{ 
int i; 
for (i = 0; i < 1000000; ++i) 
++f.y; 
}