[clang-tidy]misc-const-correctness fix fake positive of function pointer

[Changqing-JING]

No description provided.

[github-actions]

Thank you for submitting a Pull Request (PR) to the LLVM Project!

This PR will be automatically labeled and the relevant teams will be notified.

If you wish to, you can add reviewers by using the "Reviewers" section on this page.

If this is not working for you, it is probably because you do not have write permissions for the repository. In which case you can instead tag reviewers by name in a comment by using @ followed by their GitHub username.

If you have received no comments on your PR for a week, you can request a review by "ping"ing the PR by adding a comment “Ping”. The common courtesy "ping" rate is once a week. Please remember that you are asking for valuable time from other developers.

If you have further questions, they may be answered by the LLVM GitHub User Guide.

You can also ask questions in a comment on this PR, on the LLVM Discord or on the forums.

[llvmbot]

@llvm/pr-subscribers-clang-tidy

@llvm/pr-subscribers-clang-tools-extra

Author: Changqing Jing (Changqing-JING)

Changes

---

Full diff: https://github.com/llvm/llvm-project/pull/162079.diff

3 Files Affected:

• (modified) clang-tools-extra/clang-tidy/misc/ConstCorrectnessCheck.cpp (+2-1)
• (modified) clang-tools-extra/docs/ReleaseNotes.rst (+4)
• (modified) clang-tools-extra/test/clang-tidy/checkers/misc/const-correctness-pointer-as-pointers.cpp (+4)

diff --git a/clang-tools-extra/clang-tidy/misc/ConstCorrectnessCheck.cpp b/clang-tools-extra/clang-tidy/misc/ConstCorrectnessCheck.cpp
index b93f3d6a5a13b..8c25e928667df 100644
--- a/clang-tools-extra/clang-tidy/misc/ConstCorrectnessCheck.cpp
+++ b/clang-tools-extra/clang-tidy/misc/ConstCorrectnessCheck.cpp
@@ -249,7 +249,8 @@ void ConstCorrectnessCheck::check(const MatchFinder::MatchResult &Result) {
       CheckValue();
     if (WarnPointersAsPointers) {
       if (const auto *PT = dyn_cast<PointerType>(VT)) {
-        if (!PT->getPointeeType().isConstQualified())
+        if (!PT->getPointeeType().isConstQualified() &&
+            !PT->getPointeeType()->isFunctionType())
           CheckPointee();
       }
       if (const auto *AT = dyn_cast<ArrayType>(VT)) {
diff --git a/clang-tools-extra/docs/ReleaseNotes.rst b/clang-tools-extra/docs/ReleaseNotes.rst
index 7e836a7114d50..512527abf608a 100644
--- a/clang-tools-extra/docs/ReleaseNotes.rst
+++ b/clang-tools-extra/docs/ReleaseNotes.rst
@@ -321,6 +321,10 @@ Changes in existing checks
 - Improved :doc:`misc-header-include-cycle
   <clang-tidy/checks/misc/header-include-cycle>` check performance.
 
+- Improved :doc:`misc-const-correctness
+  <clang-tidy/checks/misc/const-correctness>` check by fixing false positives
+  of function pointer.
+
 - Improved :doc:`modernize-avoid-c-arrays
   <clang-tidy/checks/modernize/avoid-c-arrays>` to not diagnose array types
   which are part of an implicit instantiation of a template.
diff --git a/clang-tools-extra/test/clang-tidy/checkers/misc/const-correctness-pointer-as-pointers.cpp b/clang-tools-extra/test/clang-tidy/checkers/misc/const-correctness-pointer-as-pointers.cpp
index 2ef47266b02b0..c2c939b9ba32e 100644
--- a/clang-tools-extra/test/clang-tidy/checkers/misc/const-correctness-pointer-as-pointers.cpp
+++ b/clang-tools-extra/test/clang-tidy/checkers/misc/const-correctness-pointer-as-pointers.cpp
@@ -48,3 +48,7 @@ void ignore_const_alias() {
   p_local0 = &a[1];
 }
 
+void function_pointer_basic() {
+  void (*const fp)() = nullptr;
+  fp();
+}

[EugeneZelenko]

Please keep alphabetical order (by check name) in this list.