[clang] [llvm] [clang-tools-extra] [libcxx] [libc++] P2770R0: "Stashing stashing iterators for proper flattening" (PR #66033)

[Louis Dionne via cfe-commits]

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@@ -0,0 +1,30 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+// UNSUPPORTED: c++03
----------------
ldionne wrote:

I'd prefer if we did `UNSUPPORTED: c++03, c++11` so we can use C++14 constexpr. It's nice that you try to make it work in C++11, but TBH I think we should prioritize readability for these tests -- at the end of the day `__as_lvalue` is also not going to be used in C++11 mode so I'm not too shocked about not having coverage for it in that mode.

Then you can use multiple statements in the function below.

https://github.com/llvm/llvm-project/pull/66033