[clang] [alpha.webkit.UncountedLocalVarsChecker] Detect assignments to uncounted local variable and parameters. (PR #92639)

[Ryosuke Niwa via cfe-commits]

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@@ -135,7 +135,19 @@ class UncountedLocalVarsChecker
       bool shouldVisitImplicitCode() const { return false; }
 
       bool VisitVarDecl(VarDecl *V) {
-        Checker->visitVarDecl(V);
+        auto *Init = V->getInit();
+        if (Init && V->isLocalVarDecl())
+          Checker->visitVarDecl(V, Init);
+        return true;
+      }
+
+      bool VisitBinaryOperator(const BinaryOperator *BO) {
+        if (BO->isAssignmentOp()) {
+          if (auto *VarRef = dyn_cast<DeclRefExpr>(BO->getLHS())) {
+            if (auto *V = dyn_cast<VarDecl>(VarRef->getDecl()))
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rniwa wrote:

Hm... I don't think so. I think any assignment to a global variable is also bad if it's a raw pointer to a ref counted type. It's generally an anti-pattern to avoid.

This makes me think that the checker should probably be renamed to "UncountedVarDeclChecker" or something.

https://github.com/llvm/llvm-project/pull/92639