[clang] [CIR] Handle empty unions in record lowering (PR #172666)

[Andy Kaylor via cfe-commits]

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@@ -0,0 +1,28 @@
+// RUN: %clang_cc1 -triple x86_64-unknown-linux-gnu -fclangir -emit-cir %s -o - | FileCheck %s --check-prefix=CIR
+// RUN: %clang_cc1 -triple x86_64-unknown-linux-gnu -fclangir -emit-llvm %s -o - | FileCheck %s --check-prefix=LLVM
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andykaylor wrote:

```suggestion
// RUN: %clang_cc1 -triple x86_64-unknown-linux-gnu -fclangir -emit-llvm %s -o - | FileCheck %s --check-prefix=LLVM
// RUN: %clang_cc1 -triple x86_64-unknown-linux-gnu -emit-llvm %s -o - | FileCheck %s --check-prefix=OGCG
```
Please add OGCG checks.

https://github.com/llvm/llvm-project/pull/172666