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<p class="MsoNormal">I am new to building Clang static checkers and need some help. I am implementing a PreCall callback function that checks calls to a certain family of functions (from a local library) that takes a struct as an argument. I see how to get
the SVal and Expr for the argument using CallEvent::getArgSVal() and CallEvent::getArgExpr(). What I’m struggling with is how to go from the SVal for the struct to an SVal for one of its fields. In particular, how do I get the memory region associated with
the struct value? Once I have that, I think I know how to go from there, e.g.:<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal" style="margin-left:.5in">RecordType *structTy = structReg->getValueType()->getAsStructureType();<o:p></o:p></p>
<p class="MsoNormal" style="margin-left:.5in">assert(structTy && “Value is not a structure”);<o:p></o:p></p>
<p class="MsoNormal" style="margin-left:.5in">RecordDecl *structRD = structTy ->getDecl()->getDefinition();<o:p></o:p></p>
<p class="MsoNormal" style="margin-left:.5in">assert(structRD && “structure has no definition”);<o:p></o:p></p>
<p class="MsoNormal" style="margin-left:.5in">for (const auto *F : structRD->fields()) {<o:p></o:p></p>
<p class="MsoNormal" style="margin-left:.5in"> FieldRegion *FR = MRMgr.getFieldRegion(F, structReg);<o:p></o:p></p>
<p class="MsoNormal" style="margin-left:.5in"> if (FR->getDec()->getName() == “fieldName”)<o:p></o:p></p>
<p class="MsoNormal" style="margin-left:.5in"> size = StoreMgr.getBinding(store, loc::MemRegionVal(FR));<o:p></o:p></p>
<p class="MsoNormal" style="margin-left:.5in">}<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">But how do I get the memory region structReg? And how do I get the Store store?<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Thanks!<o:p></o:p></p>
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