[PATCH] D62978: [analyzer] trackExpressionValue(): Handle unknown values better

[Artem Dergachev via Phabricator via cfe-commits]

NoQ added a comment.

This problem is fairly complicated. We clearly need both behaviors (sometimes track until the definition, sometimes track until the collapse-to-null), and it's not clear to me right now when exactly do we need each of them. This is also not a high priority for GSoC because neither there are a lot of warnings of this kind (~15 or so) nor they're actually that false. I suggest taking this more slowly and delay this patch until we actually understand what is the right thing to do here.



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Comment at: clang/test/Analysis/null-deref-path-notes.cpp:20
                 // expected-note at -1{{Array access (via field 'd') results in a null pointer dereference}}
-  B h, a; // expected-note{{Value assigned to 'h.d'}}
   a.d == __null; // expected-note{{Assuming the condition is true}}
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This note was pretty good. It's not very clear but we should definitely keep it.


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Comment at: clang/test/Analysis/uninit-vals.m:405
     int y : 4;
-  } a, b, c; // expected-note{{'c' initialized here}}
 
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These notes are also nice, we should keep them.


CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D62978/new/

https://reviews.llvm.org/D62978