[clang] [clang][ssaf] Add EntityLinkage data structure (PR #181718)

[Balázs Benics via cfe-commits]

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@@ -0,0 +1,48 @@
+//===- unittests/Analysis/Scalable/EntityLinkageTest.cpp -----------------===//
+//
+// 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
+//
+//===----------------------------------------------------------------------===//
+
+#include "clang/Analysis/Scalable/Model/EntityLinkage.h"
+#include "gtest/gtest.h"
+
+namespace clang::ssaf {
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steakhal wrote:

IMO if the intention is to bring names from `clang` and `ssaf` to our scope, we could/should just use `using namespace`.

To me, having an anonymous namespace inside whatever namespace is just confusing.

https://github.com/llvm/llvm-project/pull/181718