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

[Balazs Benics 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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steakhal wrote:

If there is no cluster for the region, than it means that we saw no stores to that place.
Reading from such a place might be still valid for global storage duration objects such as: globals, local statics, thread local objects. This can be inferred from the memory space associated with the region.

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