Upgrade to 2022-era LLVM LIBCXX

third_party/libcxx/__config_site

@@ -0,0 +1,51 @@
+//===----------------------------------------------------------------------===//
+//
+// 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
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___CONFIG_SITE
+#define _LIBCPP___CONFIG_SITE
+
+// We get a million `error: ‘always_inline’ function might not be
+// inlinable` because we're using LLVM LIBCXX with GCC, which has
+// no exclude_from_explicit_instantiation attribute, which libcxx
+// really wants to have, and uses an always_inline hack for this.
+#pragma GCC diagnostic ignored "-Wattributes"
+
+#define _LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER
+#define _LIBCPP_DISABLE_DEPRECATION_WARNINGS
+
+#define _LIBCPP_NO_ABI_TAG
+#define _LIBCPP_ABI_VERSION 2
+#define _LIBCPP_ABI_NAMESPACE __2
+#define _LIBCPP_DISABLE_AVAILABILITY
+#define _LIBCPP_DISABLE_VISIBILITY_ANNOTATIONS
+#define _LIBCPP_HAS_NO_VENDOR_AVAILABILITY_ANNOTATIONS
+#define _LIBCPP_NO_VCRUNTIME
+#define _LIBCPP_TYPEINFO_COMPARISON_IMPLEMENTATION 1
+
+#ifdef MODE_DBG
+#define _LIBCPP_ENABLE_DEBUG_MODE
+#define _LIBCPP_ENABLE_ASSERTIONS_DEFAULT 1
+#else
+#define _LIBCPP_ENABLE_ASSERTIONS_DEFAULT 0
+#endif
+
+// PSTL backends
+#define _LIBCPP_PSTL_CPU_BACKEND_SERIAL
+#define _LIBCPP_PSTL_CPU_BACKEND_THREAD
+
+// __USE_MINGW_ANSI_STDIO gets redefined on MinGW
+#ifdef __clang__
+#  pragma clang diagnostic push
+#  pragma clang diagnostic ignored "-Wmacro-redefined"
+#endif
+
+#ifdef __clang__
+#  pragma clang diagnostic pop
+#endif
+
+#endif // _LIBCPP___CONFIG_SITE