[clang-tools-extra] Adding Separate OpenMP Offloading Backend to `libcxx/include/__algorithm/pstl_backends` (PR #66968)

[Anton Rydahl via cfe-commits]

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@@ -0,0 +1,41 @@
+//===----------------------------------------------------------------------===//
+//
+// 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
+//
+//===----------------------------------------------------------------------===//
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AntonRydahl wrote:

I think there is unfortunately a bug in the PSTL logic. I cannot compile `libcxx` if I remove the overlay header files for `any_of`, `find_if`, or `stable_sort`.

https://github.com/llvm/llvm-project/pull/66968