[PATCH] D153589: [NFC] Initialize pointer fields and remove a needless null check.

[Aaron Ballman via Phabricator via cfe-commits]

aaron.ballman added inline comments.


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Comment at: clang/lib/Analysis/CFG.cpp:4156
   // CFG generation for unevaluated operands.
-  if (S && !S->isTypeDependent() && S->isPotentiallyEvaluated())
+  if (!S->isTypeDependent() && S->isPotentiallyEvaluated())
     return VisitChildren(S);
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schittir wrote:
> schittir wrote:
> > erichkeane wrote:
> > > schittir wrote:
> > > > erichkeane wrote:
> > > > > schittir wrote:
> > > > > > erichkeane wrote:
> > > > > > > I get that we're counting on the dereference on 4145 to have made this check irrelevant, but are we sure that we KNOW that "S" is non-null here otherwise?  That is, is the bug actually 4145 doing 'alwaysAdd' without checking vs the unnecessary check here?
> > > > > > VisitCXXTypeidExpr is used only in one place - here https://github.com/llvm/llvm-project/blob/a89c9b35be08b665cc1a01d840bc20349ba1308f/clang/lib/Analysis/CFG.cpp#L2288 where S is not null. Null check for S already happens at the beginning of the method where VisitCXXTypeidExpr is called. 
> > > > > SG, an assert is perhaps not a bad idea, but LGTM.  I don't know very much about the CFG stuff, so aaron might wish to take a final look.
> > > > What is SG? 
> > > "Sounds Good"
> > Haha! 
> > Thanks for the review. 
> > SG, an assert is perhaps not a bad idea, but LGTM.  I don't know very much about the CFG stuff, so aaron might wish to take a final look.
> 
> Hi @aaron.ballman, could you please comment on this? Thank you!
I don't think an assert is necessary; I think it's a predicate to pass non-null nodes to the Visit functions in general, and I don't think we get a whole lot out of asserting in each Visit method that its given node is nonnull.


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Comment at: clang/lib/CodeGen/CGObjCGNU.cpp:58
   /// used as arguments will necessarily be available at construction time.
-  LazyRuntimeFunction()
-      : CGM(nullptr), FunctionName(nullptr), Function(nullptr) {}
+  LazyRuntimeFunction() {}
 
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schittir wrote:
> erichkeane wrote:
> > schittir wrote:
> > > erichkeane wrote:
> > > > 
> > > The comment above needs to be updated?
> > I don't think so?  It still leaves the class uninitialized.
> Right! Still valid. 
I think the comment is stale or imprecise -- the class certainly is initialized (it was being initialized previously as well, just not fully initialized). I think it may have meant "not initialized to useful values", so we could either repair it that way or remove the comment entirely.


CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D153589/new/

https://reviews.llvm.org/D153589