You don't need the sys_marker instruction. It only makes the source of the leak easier to find. But
Code:
#include <acknex.h>

void main()
{
	void* p = sys_malloc(1337);
	sys_exit(NULL);
}
should still result in
Code:
[...]
Unfreed: 943,    , 1340 bytes
Close window at 1.462

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