[clang] [coroutines][coro_lifetimebound] Detect lifetime issues with lambda captures (PR #77066)

[Utkarsh Saxena via cfe-commits]

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@@ -15845,8 +15845,10 @@ void Sema::CheckCoroutineWrapper(FunctionDecl *FD) {
   RecordDecl *RD = FD->getReturnType()->getAsRecordDecl();
   if (!RD || !RD->getUnderlyingDecl()->hasAttr<CoroReturnTypeAttr>())
     return;
-  // Allow `get_return_object()`.
-  if (FD->getDeclName().isIdentifier() &&
+  // Allow some_promise_type::get_return_object().
+  // Since we are still in the promise definition, we can only do this
+  // heuristically as the promise may not be yet associated to a coroutine.
+  if (isa<CXXMethodDecl>(FD) && FD->getDeclName().isIdentifier() &&
       FD->getName().equals("get_return_object") && FD->param_empty())
     return;
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usx95 wrote:

I do not think that would work either. For example, consider TUs with only promise definitions and no coroutine definitions. These attr would not be available even in the end of TU.

https://github.com/llvm/llvm-project/pull/77066