[PATCH] D152194: [NFC][CLANG] Fix nullptr dereference issue found by static analyzer tool

[Erich Keane via Phabricator via cfe-commits]

erichkeane added inline comments.


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Comment at: clang/lib/StaticAnalyzer/Checkers/DynamicTypePropagation.cpp:756
     if (ReceiverType->isObjCIdType() || ReceiverType->isObjCClassType() ||
         ASTCtxt.canAssignObjCInterfaces(ReceiverObjectPtrType, TrackedType)) {
       const ObjCInterfaceDecl *InterfaceDecl = TrackedType->getInterfaceDecl();
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erichkeane wrote:
> Manna wrote:
> > We are assigning: ReceiverObjectPtrType = nullptr return value from getAs.
> > ```
> > const auto *ReceiverObjectPtrType =
> >       ReceiverType->getAs<ObjCObjectPointerType>();
> > ```
> > 
> > Then we are dereferencing  nullptr ReceiverObjectPtrType when calling canAssignObjCInterfaces()
> This isn't NFC, as `ReceiverObjectPtrType` is only used here.  If the `MessageExpr` `ReceiverKind` is not `Instance` or `Class`, we never dereference this.  So the declaration should be in this branch.
Oh, and ALSO, we don't dereference it if `ReceiverType` is `ObjCIdType` or `ObhjCClassType`.


Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D152194/new/

https://reviews.llvm.org/D152194