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struct Foo
{
 int* a;
 int* b;
};
 
std::atomic <Foo*> foo_head[10];
int foo_array[10][10];
 
// consume operation starts a dependency chain, which escapes this function
[[carries_dependency]] Foo* f(int i)
{
 return foo_head[i].load(memory_order_consume);
}
 
// the dependency chain enters this function through the right parameter and is
// killed before the function ends (so no extra acquire operation takes place)
int g(int* x, int* y [[carries_dependency]])
{
 return std::kill_dependency(foo_array[*x][*y]);
}

[[carries_dependency]] struct Foo* f(int i);
int g(int* x, int* y [[carries_dependency]]);
 
int c = 3;
void h(int i)
{
 Foo* p;
 p = f(i); // dependency chain started inside f continues into p without undue acquire
 do_something_with(g(&c, p->a)); // p->b is not brought in from the cache
 do_something_with(g(p->a, &c)); // left argument does not have the carries_dependency
 // attribute: memory acquire fence may be issued
 // p->b becomes visible before g() is entered
}