diff --git a/linux-x64/clang/include/clang-tidy/concurrency/MtUnsafeCheck.h b/linux-x64/clang/include/clang-tidy/concurrency/MtUnsafeCheck.h
new file mode 100644
index 0000000..9196194
--- /dev/null
+++ b/linux-x64/clang/include/clang-tidy/concurrency/MtUnsafeCheck.h
@@ -0,0 +1,43 @@
+//===--- MtUnsafeCheck.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_CONCURRENCY_MTUNSAFECHECK_H
+#define LLVM_CLANG_TOOLS_EXTRA_CLANG_TIDY_CONCURRENCY_MTUNSAFECHECK_H
+
+#include "../ClangTidyCheck.h"
+
+namespace clang {
+namespace tidy {
+namespace concurrency {
+
+/// Checks that non-thread-safe functions are not used.
+///
+/// For the user-facing documentation see:
+/// http://clang.llvm.org/extra/clang-tidy/checks/threads-mt-unsafe.html
+class MtUnsafeCheck : public ClangTidyCheck {
+public:
+  MtUnsafeCheck(StringRef Name, ClangTidyContext *Context);
+  void storeOptions(ClangTidyOptions::OptionMap &Opts) override;
+  void registerMatchers(ast_matchers::MatchFinder *Finder) override;
+  void check(const ast_matchers::MatchFinder::MatchResult &Result) override;
+
+  enum class FunctionSet {
+    Posix,
+    Glibc,
+    Any,
+  };
+
+private:
+  const FunctionSet FuncSet;
+};
+
+} // namespace concurrency
+} // namespace tidy
+} // namespace clang
+
+#endif // LLVM_CLANG_TOOLS_EXTRA_CLANG_TIDY_CONCURRENCY_MTUNSAFECHECK_H