[clang] [Clang][Sema] Error message refers to `__begin1` with `constexpr` variable in range-based for loop (PR #218145)

[Shengxin Pei via cfe-commits]

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@@ -0,0 +1,87 @@
+// RUN: %clang_cc1 -std=c++11 -fsyntax-only -verify %s
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TPPPP72 wrote:

As I recall, we have test files for `constexpr-for`; you can simply move those tests over.

https://github.com/llvm/llvm-project/pull/218145