Differed tax

If a company incurred loss(as per books of accounts maintained under Companies Act), how to treat that loss as per companies act & as per income tax act.In this case whether differed tax will arise or not, if there is profit as per Income Tax Act because of heavy inadmissible expenses.how to caluclate differed tax in the following cases.

a)if assessee file the return as per sec 139(3)

b)if the assessee did not file return as per sec 139(3)