For building=roof without layer tag, intersecting with roads, footways, cycleways etc validator should mention that typical roof is above other objects and it should have "layer=1" tag

[mkoniecz]

"Crossing ways (1)" is quite mysterious "Roof crossing with other objects, maybe it should have layer=1 tag?" (or something like this) would be smarter.

Current report is quite confusing (for me, reporter of #9362 and probably others).

This suggestion definitely should be given for crossing with highway=*, and must not be given for crossing with buildings. Not sure about other types of objects.

Note that after adding this special case layerless, intersecting roofs should not appear also in "Crossing ways" category.

I encountered this difficulty on ​osmwww:browse/way/248676077

Repository Root: http://josm.openstreetmap.de/svn
Build-Date: 2013-11-25 02:34:44
Last Changed Author: Don-vip
Revision: 6413
Repository UUID: 0c6e7542-c601-0410-84e7-c038aed88b3b
URL: http://josm.openstreetmap.de/svn/trunk
Last Changed Date: 2013-11-25 02:19:43 +0100 (Mon, 25 Nov 2013)
Last Changed Rev: 6413

Identification: JOSM/1.5 (6413 en_GB) Windows 7 32-Bit
Memory Usage: 108 MB / 247 MB (31 MB allocated, but free)
Java version: 1.7.0_45, Oracle Corporation, Java HotSpot(TM) Client VM
Dataset consistency test: No problems found

Plugin: OpeningHoursEditor (29854)
Plugin: notes (v0.6)

[aceman]

... and must not be given for crossing with buildings.

Why? A building (of any type, without layer tag) crossing into other buildings (or any ways) seems like an error and is currently reported. Roof is no exception without a layer.

[mkoniecz]

"must not" applies to displaying a new, more specific warning message.

building/building crossing would receive current "Crossing ways".