Add some alignment info where LLVM might otherwise be more pessimistic. In particular, %.nest_arg is always aligned even though it's bitcast from i8*. Pointers in vtables are also guaranteed to be stored at aligned addresses.

module tangotests.vararg1;

import tango.stdc.stdio;

void func(int[] arr...)
{
    printf("1,2,4,5,6 == %d,%d,%d,%d,%d\n", arr[0],arr[1],arr[2],arr[3],arr[4]);
}

void main()
{
    func(1,2,4,5,6);
}