Fix IterFnError

✅ Solution

The "IterFnError" usually arises from inconsistencies between the expected and actual return types or calling conventions of an iterator function, especially when interfacing with C code, such as libc on certain architectures. To fix it, carefully examine the iterator function's signature and ensure it precisely matches the C function's definition, including ABI considerations (e.g., using `@call(.C)` or `@call(.Auto)`); verify the return type of the iterator matches what is expected by the caller. Review any platform-specific compiler options that might affect calling conventions to ensure compatibility.