Union copy

["Luís]

On Wednesday, 23 October 2013 at 16:58:21 UTC, Dicebot wrote:
> By simply printing all bytes of a union as %b (binary) and 
> checking bit pattern as per http://en.wikipedia.org/wiki/NaN :) 
> I am not really proficient in IEEE stuff so checking bits is 
> only thing I am capable of :P

I'm not sure I follow. The values I have are:

src.l:       7ff7a50200000000
dst1.l:    7ff7a50200000000 
(0111111111110111101001010000001000000000000000000000000000000000)
dst2.l:	7fffa50200000000 
(0111111111111111101001010000001000000000000000000000000000000000)
dst1.d:     nan
dst2.d:     nan
dst1.payload:   3d2810
dst2.payload:   3d2810

Making the bit pattern more explicit:

S       E     F       P
0 11111111111 0 
111101001010000001000000000000000000000000000000000
0 11111111111 1 
111101001010000001000000000000000000000000000000000

Is the only different bit not the quiet/signaling NaN flag? Why 
do you say that the payload is different?