Another problem with the C code, which is perhaps even more subtle, is the usage of `int` for the length, capacity, and loop index. On 64-bit platforms these variables will overflow for very large arrays, which will likely break the entire implementation. The call to `malloc()` should give a signed-to-unsigned conversion warning which will hint about this, but unfortunately many people ignore integer warnings. Incidentally, this could also be caught by compiling with `-ftrapv` or `-fsanitize=undefined`, but this problem is only triggered in a rather extreme corner case that is unlikely to be exposed during testing. The correct integer type to use is `size_t`, which is guaranteed to be large enough to hold the size of any object in memory.