[clang] [WebKit checkers] Trivial function analysis ignores some nodelete annotation (PR #183970)

[Ryosuke Niwa via cfe-commits]

================
@@ -454,10 +454,29 @@ bool isPtrConversion(const FunctionDecl *F) {
   return false;
 }
 
-bool isNoDeleteFunction(const FunctionDecl *F) {
+static bool isNoDeleteFunctionDecl(const FunctionDecl *F) {
   return typeAnnotationForReturnType(F) == WebKitAnnotation::NoDelete;
 }
 
+bool isNoDeleteFunction(const FunctionDecl *F) {
+  if (llvm::any_of(F->redecls(), isNoDeleteFunctionDecl))
+    return true;
+
+  const auto *MD = dyn_cast<CXXMethodDecl>(F);
+  if (!MD || !MD->isVirtual())
+    return false;
+
+  auto Overriders = llvm::to_vector(MD->overridden_methods());
+  while (!Overriders.empty()) {
+    const auto *Fn = Overriders.pop_back_val();
+    llvm::append_range(Overriders, Fn->overridden_methods());
+    if (isNoDeleteFunctionDecl(Fn))
+      return true;
+  }
+
+  return false;
----------------
rniwa wrote:

We do! It looks like we don't have a test coverage for that so I'll add one

https://github.com/llvm/llvm-project/pull/183970