JOSM lockup when loading duplicate data

[framm]

JOSM (latest - 2328) freezes in the "preparing data set..." stage, emitting lots of

can not split, but too deep: 23 size: 19

messages on the console. This happens when I try to load the following URL:

GET ​http://api.openstreetmap.org/api/0.6/map?bbox=103.83873242862792,13.368442260419624,103.86928061454346,13.394550303033487

The data in this area is broken, seven identical imports have been made on top of each other.

PLEASE DO NOT FIX THE DATA, this is being looked after already; it's just that JOSM should handle this gracefully. (Maybe something else is wrong with the data - loading a small section of it does work, just the whole thing doesn't.)

I am attaching a saved version of the above data; the lock-up also happens when opening the file.

[framm]

data file that breaks josm

[stoecker]

The message comes from QuadBuckets code.

[hansendc]

(In [2423]) This fixes #3796.

The issue was that we somehow ended up with a branch node
that had no valid children. We assumed in the iterator
that any node with no content must have children, but
that was wrong.

[anonymous]

Thanks for providing the trouble data. It helped finding the bug immensely.