[PATCH] D158156: [analyzer] Add C++ array delete checker

[Donát Nagy via Phabricator via cfe-commits]

donat.nagy added inline comments.


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Comment at: clang/test/Analysis/ArrayDelete.cpp:85-88
+    Derived *d3 = new DoubleDerived[10];
+    Base *b3 = d3; // expected-note{{Conversion from derived to base happened here}}
+    delete[] b3; // expected-warning{{Deleting an array of polymorphic objects is undefined}}
+    // expected-note at -1{{Deleting an array of polymorphic objects is undefined}}
----------------
steakhal wrote:
> donat.nagy wrote:
> > steakhal wrote:
> > > Hmm, the static type of `d3` doesn't tell us much about how it refers to an object of type `DoubleDerived`.
> > > To me, it would make sense to have multiple `Conversion from derived to base happened here`, even telling us what static type it converted to what other static type in the message.
> > > And it should add a new visitor of the same kind tracking the castee.
> > > 
> > > ```
> > > Derived *d3 = new DoubleDerived[10]; // note: `DoubleDerived` -> `Derived` here
> > > Base *b3 = d3; // note: `Derived` -> `Base` here
> > > delete[] b3; // warn: Deleting `Derived` objects as `Base` objects.
> > > ```
> > > WDYT @donat.nagy ?
> > I agree that it would be good to be good to mention the class names in the message.
> Do you also agree that we should have all steps where such a conversion happened?
> Notice the 2 `note:` markers in my example. @donat.nagy 
It would be a nice addition if it wouldn't seriously complicate the implementation.

If we want to report multiple/all conversions, then we would need to create messages for back-and-forth conversions (e.g. allocating Derived, converting it to Base, back to Derived, back to Base, then deleting it illegally).


CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D158156/new/

https://reviews.llvm.org/D158156