[clang] [clang][Sema] Fix initialization of GRO when GRO-return type mismatches (CWG2563) (PR #179156)

[Chuanqi Xu via cfe-commits]

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@@ -1870,7 +1870,8 @@ bool CoroutineStmtBuilder::makeGroDeclAndReturnStmt() {
   } else {
     GroDecl = VarDecl::Create(
         S.Context, &FD, FD.getLocation(), FD.getLocation(),
-        &S.PP.getIdentifierTable().get("__coro_gro"), GroType,
+        &S.PP.getIdentifierTable().get("__coro_gro"),
+        S.BuildDecltypeType(ReturnValue).getCanonicalType(),
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ChuanqiXu9 wrote:

Just curious, why `getCanonicalType`?

https://github.com/llvm/llvm-project/pull/179156