This issue has been reported by French IGN.
During the public review, French IGN proposes to change the wording (function code not provided) in table 2/resource locator (Draft 6 of the GeoDCAT-AP specification) and put this line first in the list since the function code element is not explicitly asked by INSPIRE. Therefore, in most cases it might not be provided.
In addition, the mapping to be used in this case should be in first position in the list. Moreover the wording is not precise enough: it is not “missing value for function code”, but “function code not provided”.
They also ask whether it is sure that the mapping of “offlineAccess” to “accessURL” seems semantically strange. Why not using foaf:page, for the mapping of order (as it is done for search)?