[clang] [analyzer] New optin.taint.TaintAlloc checker for catching unbounded memory allocation calls (PR #92420)

[Balazs Benics via cfe-commits]

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@@ -1695,6 +1707,12 @@ MallocChecker::processNewAllocation(const CXXAllocatorCall &Call,
   // MallocUpdateRefState() instead of MallocMemAux() which breaks the
   // existing binding.
   SVal Target = Call.getObjectUnderConstruction();
+  if (Call.getOriginExpr()->isArray()) {
+    std::optional<const Expr *> SizeEx = NE->getArraySize();
+    if (SizeEx)
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steakhal wrote:

```suggestion
    if (auto SizeEx = NE->getArraySize())
```

https://github.com/llvm/llvm-project/pull/92420