[clang] [clang][analyzer] CallAndMessage warnings at pointer to uninitialized struct (PR #164600)

[Balázs Kéri via cfe-commits]

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@@ -212,8 +210,14 @@ bool CallAndMessageChecker::uninitRefOrPointer(
 
   if (const MemRegion *SValMemRegion = V.getAsRegion()) {
     const ProgramStateRef State = C.getState();
-    const SVal PSV = State->getSVal(SValMemRegion, C.getASTContext().CharTy);
-    if (PSV.isUndef()) {
+    QualType T = ParamDecl->getType()->getPointeeType();
+    if (T->isVoidType())
+      T = C.getASTContext().CharTy;
+    const SVal PSV = State->getSVal(SValMemRegion, T);
+    bool IsUndef = PSV.isUndef();
+    if (auto LCV = PSV.getAs<nonloc::LazyCompoundVal>())
+      IsUndef = LCV->getStore() == nullptr;
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balazske wrote:

Is it possible that there is no binding at all? Even with `iterBindings` over subregions and super-regions, no binding is found. `LazyCoupoundValue` is not necessary for this search (memregion and store is available from elsewhere). The LCV can contain a null `Store` pointer (and exactly this case looks interesting).

https://github.com/llvm/llvm-project/pull/164600