[PATCH] Static analysis checker for catch handler inversion

[Aaron Ballman]

On Mon, Oct 27, 2014 at 7:30 PM, Jordan Rose <jordan_rose at apple.com> wrote:
> Nifty! But do you think this is cheap enough for a general compiler warning? It certainly doesn't depend on the analyzer's path-sensitive analysis, so it's mostly just how much we care about the cost of isDerivedFrom.

This should be relatively inexpensive, so it may make sense as a
general compiler warning if others feel that's a better approach.

Thanks!

~Aaron
>
> Jordan
>
>
>> On Oct 27, 2014, at 15:30, Aaron Ballman <aaron at aaronballman.com> wrote:
>>
>> It is possible to write catch handlers such that they never execute
>> due to inversion of the class hierarchy, such as:
>>
>> class B {};
>> class D : public B {};
>>
>> void f() {
>>  try {
>>    // ...
>>  } catch (B &b) {
>>    // ...
>>  } catch (D &d) {
>>    // ...
>>  }
>> }
>>
>> This patch causes a static analysis warning to be generated for code
>> where a catch handler cannot execute due to class hierarchy inversion
>> with regards to other catch handlers for the same try block.
>>
>> This issue is covered by CERT's secure coding rule:
>> https://www.securecoding.cert.org/confluence/display/cplusplus/ERR36-CPP.+Catch+handlers+should+order+their+parameter+types+from+most+derived+to+least+derived
>>
>> It's also covered by MISRA rule 15-3-6.
>>
>> ~Aaron
>> <CatchHandlerChecker.patch>
>