Control File: sub-package name used with incompatible field

An .info file is a control file with declarations to support multiple sub-packages built from the same project. The most common usage is to create a run-time, a development, and a documentation package for a project. These are defined with the Sub-Package field.

Sub-Package: run-time*, development, documentation

The file can then specify a set of fields, some of which are specific to one of the sub-package. For example, it is common to set the architecture to "all" for the documentation package:

Architecture: $(architecture())
Architecture/documentation: all

Some fields do not accept such specifications simply because they are expected to be exactly the same across the entire set of packages for one project. For example, the URI for people to use to report bugs cannot be different in each package of one project. Thus using a sub-package name on the Bugs field generates an error.

VALIDSub-Package: run-time*, dev, doc
Architecture: $(architecture())
Architecture/doc: all
INVALIDSub-Package: run-time*, dev, doc