[clang-tools-extra] [clang-tidy]unused using decls only check cpp files (PR #77335)

[Congcong Cai via cfe-commits]

https://github.com/HerrCai0907 updated https://github.com/llvm/llvm-project/pull/77335

>From 832bb78fd8cac372ec5560bb280f11e11be8d2e6 Mon Sep 17 00:00:00 2001
From: Congcong Cai <congcongcai0907 at 163.com>
Date: Tue, 9 Jan 2024 00:41:33 +0800
Subject: [PATCH] [clang-tidy]unused using decls only check cpp files

---
 clang-tools-extra/clang-tidy/misc/UnusedUsingDeclsCheck.h | 3 +++
 clang-tools-extra/docs/ReleaseNotes.rst                   | 2 +-
 2 files changed, 4 insertions(+), 1 deletion(-)

diff --git a/clang-tools-extra/clang-tidy/misc/UnusedUsingDeclsCheck.h b/clang-tools-extra/clang-tidy/misc/UnusedUsingDeclsCheck.h
index fa2a8799d098c3..498b3ffd2678c3 100644
--- a/clang-tools-extra/clang-tidy/misc/UnusedUsingDeclsCheck.h
+++ b/clang-tools-extra/clang-tidy/misc/UnusedUsingDeclsCheck.h
@@ -26,6 +26,9 @@ class UnusedUsingDeclsCheck : public ClangTidyCheck {
   void registerMatchers(ast_matchers::MatchFinder *Finder) override;
   void check(const ast_matchers::MatchFinder::MatchResult &Result) override;
   void onEndOfTranslationUnit() override;
+  bool isLanguageVersionSupported(const LangOptions &LangOpts) const override {
+    return LangOpts.CPlusPlus;
+  }
 
 private:
   void removeFromFoundDecls(const Decl *D);
diff --git a/clang-tools-extra/docs/ReleaseNotes.rst b/clang-tools-extra/docs/ReleaseNotes.rst
index 1bd5a72126c10b..d7f46cede0370c 100644
--- a/clang-tools-extra/docs/ReleaseNotes.rst
+++ b/clang-tools-extra/docs/ReleaseNotes.rst
@@ -382,7 +382,7 @@ Changes in existing checks
 
 - Improved :doc:`misc-unused-using-decls
   <clang-tidy/checks/misc/unused-using-decls>` check to avoid false positive when
-  using in elaborated type.
+  using in elaborated type and only check cpp files.
 
 - Improved :doc:`modernize-avoid-bind
   <clang-tidy/checks/modernize/avoid-bind>` check to