[clang] [CIR] Implement Statement Expressions (PR #153677)

[Andy Kaylor via cfe-commits]

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@@ -1178,11 +1178,11 @@ static void pushTemporaryCleanup(CIRGenFunction &cgf,
                                         ->getBaseElementTypeUnsafe()
                                         ->getAs<clang::RecordType>()) {
     // Get the destructor for the reference temporary.
-    auto *classDecl =
-        cast<CXXRecordDecl>(rt->getOriginalDecl()->getDefinitionOrSelf());
-    if (!classDecl->hasTrivialDestructor())
-      referenceTemporaryDtor =
-          classDecl->getDefinitionOrSelf()->getDestructor();
+    if (const auto *classDecl = dyn_cast<CXXRecordDecl>(
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andykaylor wrote:

Since this was a `cast` before, it would have asserted if the return value was null. Are there cases where this returns null?

https://github.com/llvm/llvm-project/pull/153677