[PATCH] D73898: [analyzer] StdLibraryFunctionsChecker: Add argument constraints

[Artem Dergachev via Phabricator via cfe-commits]

NoQ added inline comments.


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Comment at: clang/lib/StaticAnalyzer/Checkers/StdLibraryFunctionsChecker.cpp:409
 
-  Optional<Summary> FoundSummary = findFunctionSummary(FD, CE, C);
+  for (const ValueConstraintPtr& VC : Summary.ArgConstraints) {
+    ProgramStateRef SuccessSt = VC->apply(State, Call, Summary);
----------------
martong wrote:
> NoQ wrote:
> > Maybe we should add an assertion that the same argument isn't specified multiple times.
> I think there could be cases when we want to have e.g. a not-null constraint on the 1st argument, but also we want to express that the 1st argument's size is described by the 2nd argument. I am planning to implement such a constraints in the future. In that case we would have two constraints on the 1st argument and the assert would fire.
Wait, i misunderstood the code. It's even worse than that: you're adding transitions in a loop, so it'll cause state splits for every constraint. Because you do not intend to create multiple branches here, there needs to be exactly one `addTransition` performed every time `checkPreCall` is called. I.e., for now this code is breaking everything whenever there's more than one constraint, regardless of whether it's on the same argument.


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  https://reviews.llvm.org/D73898/new/

https://reviews.llvm.org/D73898