Rule M9-3-1 (required, implementation, automated)
Const member functions shall not return non-const pointers or references to class-data. See MISRA C++ 2008 [7] Note: This rule applies to smart pointers, too. Note: “The class-data for a class is all non-static member data and any resources acquired in the constructor or released in the destructor.” [MISRA C++ 2008 [7]]