Why is this type alias causing a compilation error (C++)?

I'm writing an LLVM pass that renames functions amongst other things. I have this small piece of code

// Get function arguments
std::vector<Argument*> Arguments;
for (auto Arg = F.arg_begin(); Arg != F.arg_end(); ++Arg)
{
  Type *ArgTy = Arg->getType();

  if (ArgTy->isFloatingPointTy())
  {
    errs() << "Cannot test function: " << F.getName() << " (floating point arguments)\n";
    return false;
  }
  Arguments.push_back(Arg);
}

The line Arguments.push_back(Arg) is causing a compilation error:

no known conversion for argument 1 from ‘llvm::ilist_iterator<llvm::ilist_detail::node_options<llvm::Argument, false, false, void>, false, false>’ to ‘llvm::Argument* const&’.

However, in the header file llvm/IR/Function.h (source), arg_iterator is declared as an alias for the type Argument *, and the functions arg_begin() and arg_end() called by a Function instance, return an arg_iterator() type. So why am I getting the type error? Does it have something to do with the use of the auto keyword?