# Using EdgeList on a once empty Graph crashes the kernel

Note: this is fixed in version 9.

Calling EdgeList on a non-empty graph which was previously empty causes the math kernel to crash.

For example,

EdgeList[
Graph[{}],
{x, y}],
DirectedEdge[x, y]
]
]


and

EdgeList[
VertexDelete[
Graph[{DirectedEdge[x,y]}],
{x, y}],
{x, y}],
DirectedEdge[x, y]
]
]


both will crash the kernel.

I've recently posted this issue to the Mathematica Bug List but haven't received any response. Is this the correct place to report bugs, or should I use the contact page for WRI instead.

Can other people reproduce this? Also, how could WRI possibly mess this up / not notice this?

Edit: fixed second example.

• Yes, I can reproduce this on 8.04 on OSX – rm -rf Aug 22 '12 at 5:08
• I can reproduce it on 8.0.4 on win7 x64 – Silvia Aug 22 '12 at 6:52
• @Silvia, do both issues crash on win7 x64, or just the first one? – user21 Aug 22 '12 at 15:08
• @ruebenko Sorry for my preconception that two examples were essentially the same. So I tested them both, the first crashed while the second prompted errors about excess arguments only and stopped normally. – Silvia Aug 22 '12 at 15:24
• @Silvia, thanks that's what I see too. – user21 Aug 22 '12 at 15:33