[clang] [llvm] [Clang] C++20 Coroutines: Introduce Frontend Attribute [[clang::coro_await_elidable]] (PR #99282)

[Yuxuan Chen via cfe-commits]

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@@ -848,7 +862,21 @@ ExprResult Sema::BuildUnresolvedCoawaitExpr(SourceLocation Loc, Expr *Operand,
   }
 
   auto *RD = Promise->getType()->getAsCXXRecordDecl();
-  auto *Transformed = Operand;
+  bool InplaceCall =
+      isCoroInplaceCall(Operand) &&
+      isAttributedCoroInplaceTask(
+          getCurFunctionDecl(/*AllowLambda=*/true)->getReturnType());
+
+  if (InplaceCall) {
+    if (auto *Temporary = dyn_cast<CXXBindTemporaryExpr>(Operand)) {
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yuxuanchen1997 wrote:

Correct me if I am wrong: `InplaceCall` already required the expression to be PRValue. Looking at the AST we are dealing with in this pattern, I don't think a MaterializeTemporary would be inserted here? 

https://github.com/llvm/llvm-project/pull/99282