In b2 $(a) in A B C is true when $(a) is empty (empty set is a subset of any set). So, the tag will produce a result for untyped targets, which is clearly not intended.
This currently does not happen anyway, because b2 doesn't run <tag>s for untyped targets, but I intend to change that, so that users could do make a : : @make-rule : <tag>@tag-rule ;
In b2
$(a) in A B C
is true when$(a)
is empty (empty set is a subset of any set). So, the tag will produce a result for untyped targets, which is clearly not intended.This currently does not happen anyway, because b2 doesn't run
<tag>
s for untyped targets, but I intend to change that, so that users could domake a : : @make-rule : <tag>@tag-rule ;