[clang-tools-extra] [clang-tidy] add modernize-use-constexpr check (PR #146553)

[via cfe-commits]

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@@ -0,0 +1,47 @@
+//===--- UseUseConstexprCheck.h - clang-tidy --------------------*- C++ -*-===//
+//
+// 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 LLVM_CLANG_TOOLS_EXTRA_CLANG_TIDY_MODERNIZE_USECONSTEXPRCHECK_H
+#define LLVM_CLANG_TOOLS_EXTRA_CLANG_TIDY_MODERNIZE_USECONSTEXPRCHECK_H
+
+#include "../ClangTidyCheck.h"
+#include "clang/AST/Decl.h"
+#include "llvm/ADT/DenseMap.h"
+#include "llvm/ADT/SmallPtrSet.h"
+
+namespace clang::tidy::modernize {
+
+/// Finds functions and variables that can be declared 'constexpr'.
+///
+/// For the user-facing documentation see:
+/// http://clang.llvm.org/extra/clang-tidy/checks/modernize/use-constexpr.html
----------------
EugeneZelenko wrote:

```suggestion
/// https://clang.llvm.org/extra/clang-tidy/checks/modernize/use-constexpr.html
```

https://github.com/llvm/llvm-project/pull/146553