[clang-tools-extra] [clang-tidy] Add `bugprone-pointer-arithmetic-on-polymorphic-object` check (PR #91951)

[Piotr Zegar via cfe-commits]

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@@ -0,0 +1,38 @@
+//===--- PointerArithmeticOnPolymorphicObjectCheck.h ------------*- 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_BUGPRONE_POINTERARITHMETICONPOLYMORPHICOBJECTCHECK_H
+#define LLVM_CLANG_TOOLS_EXTRA_CLANG_TIDY_BUGPRONE_POINTERARITHMETICONPOLYMORPHICOBJECTCHECK_H
+
+#include "../ClangTidyCheck.h"
+
+namespace clang::tidy::bugprone {
+
+/// Finds pointer arithmetic performed on classes that declare a
+/// virtual function.
+///
+/// For the user-facing documentation see:
+/// http://clang.llvm.org/extra/clang-tidy/checks/bugprone/pointer-arithmetic-on-polymorphic-object.html
+class PointerArithmeticOnPolymorphicObjectCheck : public ClangTidyCheck {
+public:
+  PointerArithmeticOnPolymorphicObjectCheck(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;
+  bool isLanguageVersionSupported(const LangOptions &LangOpts) const override {
+    return LangOpts.CPlusPlus;
+  }
+
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PiotrZSL wrote:

Exclude implicit code with TK_IgnoreUnlessSpelledInSource here (look into other checks).

https://github.com/llvm/llvm-project/pull/91951