Function syscall_wrapper_impl 

#[unsafe(no_mangle)]
pub extern "C-unwind" fn syscall_wrapper_impl(
    syscall_no: u64,
    arg1: u64,
    arg2: u64,
    arg3: u64,
    arg4: u64,
    arg5: u64,
    arg6: u64,
    arg7: u64,
) -> SysErr

The symbol thruput-xdr’s syscalls_mock extern declaration links against; forwards to perform_mocked_syscall.