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@@ -100,6 +100,8 @@ This parts contains notes regarding the implementation of the mutator executable #### mutator-lvl0 * The implementation for the Misra-C:2004 rules 11.1,11.2,11.4 and 11.5 might seem unorthodox. Here's the explanation. The essence of the 11.1,11.2,11.3 and 11.4 rules as a collective is (after being translated into clang AST) that any time there is an `ImplicitCastExpr` or `CStyleCastExpr` that has `CastKind = CK_BitCast` the rule-checker should tag it. `CK_BitCast` means that a bit-pattern of one kind is being interpreted as a bit-pattern of another kind which is dangerous. This `CastKind` couple with the other `CastKinds` provided by the clang frontend enable us to tag cases where there is a deviation from the specified rules. Of course it is possible to check for exactly what the rules ask for but execution-time.<br/> +* The implementation for the Misra-C:2004 rule 16.7 only checks for changes made to the pointee object when the pointer is the LHS of a binary `=` operator. Changes can be made to the pointee object through UnaryOperators `++` and `--` but since the `*` UnaryOperator is also involved, the behaviour is undefined as to which unaryOperator is evaluated at first so depending on the original build toolchain's implementation, it could modify the pointer itself or the pointee object. such cases are already being tagged by 12.13 and the fix to that rule will either make the source code in a way that will be tagged by 16.7 or fix it so it wont get tagged. Either way, it is pointless to look for changes to pointee objects through `++` and `--` operators, postfix or prefix. Do note that even if at later times, mutator supports pragmas for different compiler implementation behaviours, the last argument still stands.<br/> + ### Dev Method TDD tests are created for each added feature which are stored under the **test** folder in the repo.<br/> Smoke tests and Daily builds are conducted to make sure the code base builds correctly more than once every day.<br/> |