invalid read with hidden iemgui on GOP canvas

1. run Pd with valgrind pd-l2ork -nrt
2. create a new patch
3. create a [pd] and make it graph-on-parent
4. open [pd]
5. create an iemgui (I tested with [bng] and [nbx]
6. choose "Properties" and click the "init" checkbox
7. position the new iemgui outside the red graph-on-parent rectangle
8. close the subpatch
9. select the [pd] object on the parent canvas
10. click <Delete> or <Backspace> (I tested with <Delete>)

Bug!

A chain of invalid reads gets triggered for the iemgui.

Doesn't happen if the iemgui is visible on the graph-on-parent. Also doesn't happen if the iemgui doesn't have "init" checked.

Edit: also can happen if the subpatch isn't a GOP subpatch.