[clang] Detect a return value of Ref<T> & RefPtr<T> (PR #81580)

[Ryosuke Niwa via cfe-commits]

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@@ -118,6 +118,26 @@ bool isCtorOfRefCounted(const clang::FunctionDecl *F) {
          || FunctionName == "Identifier";
 }
 
+bool isReturnValueRefCounted(const clang::FunctionDecl *F) {
+  assert(F);
+  auto *type = F->getReturnType().getTypePtrOrNull();
+  while (type) {
+    if (auto *elaboratedT = dyn_cast<ElaboratedType>(type)) {
+      type = elaboratedT->desugar().getTypePtrOrNull();
+      continue;
+    }
+    if (auto *specialT = dyn_cast<TemplateSpecializationType>(type)) {
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rniwa wrote:

Sounds good. Fixed.

https://github.com/llvm/llvm-project/pull/81580