id	summary	reporter	owner	description	type	status	priority	milestone	component	version	resolution	keywords	cc
22556	[patch] Complain about building=roof + addr:*	Famlam	team	"Currently there are about 50k cases where addr:* tags are placed on a building with `building=roof` (not to be confused with building:part=roof)

Addresses are typically not located on (in?) the roof of the building, but rather point at the object that's under the roof. Additionally, as the majority of these tags seem to be for `amenity=fuel` (60k in combination with `building=roof`), the wiki page of `amenity=fuel` also indicates one should make a separate area for the roof. 
https://wiki.openstreetmap.org/wiki/Tag:amenity%3Dfuel
https://wiki.openstreetmap.org/wiki/Tag:building%3Droof

Hence, I would propose to add either:
{{{#!rule
way[building=roof][amenity=fuel] {
  throwWarning: tr(""{0} together with {1}, usually {1} is located underneath the roof"", ""{0.tag}"", ""{1.tag}"");
  group: tr(""suspicious tag combination"");
}
}}}
or
{{{#!rule
way[building=roof][/^addr:/] {
  throwWarning: tr(""{0} together with {1}, usually addresses refer to objects underneath the roof"", ""{0.tag}"", ""{1.key}"");
  group: tr(""suspicious tag combination"");
}
}}}"	enhancement	new	normal		Core validator			roof fuel