[clang] [libcxxabi] [llvm] [Clang] Mangling of pack indexing type and expression for itanium (PR #123513)

[Aaron Ballman via cfe-commits]

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@@ -0,0 +1,34 @@
+// RUN: %clang_cc1 -emit-llvm %s -o - -triple=x86_64-linux-gnu -std=c++2c | FileCheck %s
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AaronBallman wrote:

```suggestion
// RUN: %clang_cc1 -emit-llvm %s -o - -triple %itanium_abi_triple -std=c++2c | FileCheck %s
```

https://github.com/llvm/llvm-project/pull/123513