[clang-tools-extra] [clang-tidy] Add check 'bugprone-cast-to-struct' (PR #153428)

[Baranov Victor via cfe-commits]

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@@ -0,0 +1,82 @@
+//===--- CastToStructCheck.cpp - clang-tidy -------------------------------===//
+//
+// 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
+//
+//===----------------------------------------------------------------------===//
+
+#include "CastToStructCheck.h"
+#include "../utils/Matchers.h"
+#include "../utils/OptionsUtils.h"
+#include "clang/ASTMatchers/ASTMatchFinder.h"
+
+using namespace clang::ast_matchers;
+
+namespace clang::tidy::bugprone {
+
+CastToStructCheck::CastToStructCheck(StringRef Name, ClangTidyContext *Context)
+    : ClangTidyCheck(Name, Context),
+      IgnoredFunctions(
+          utils::options::parseStringList(Options.get("IgnoredFunctions", ""))),
+      IgnoredFromTypes(
+          utils::options::parseStringList(Options.get("IgnoredFromTypes", ""))),
+      IgnoredToTypes(
+          utils::options::parseStringList(Options.get("IgnoredToTypes", ""))) {}
+
+void CastToStructCheck::storeOptions(ClangTidyOptions::OptionMap &Opts) {
+  Options.store(Opts, "IgnoredFunctions",
+                utils::options::serializeStringList(IgnoredFunctions));
+  Options.store(Opts, "IgnoredFromTypes",
+                utils::options::serializeStringList(IgnoredFromTypes));
+  Options.store(Opts, "IgnoredToTypes",
+                utils::options::serializeStringList(IgnoredToTypes));
+}
+
+void CastToStructCheck::registerMatchers(MatchFinder *Finder) {
+  auto FromPointee =
+      qualType(hasUnqualifiedDesugaredType(type().bind("FromType")),
+               unless(qualType(matchers::matchesAnyListedTypeName(
+                   IgnoredFromTypes, false))))
+          .bind("FromPointee");
+  auto ToPointee =
+      qualType(hasUnqualifiedDesugaredType(recordType().bind("ToType")),
+               unless(qualType(
+                   matchers::matchesAnyListedTypeName(IgnoredToTypes, false))))
+          .bind("ToPointee");
+  auto FromPtrType = qualType(pointsTo(FromPointee)).bind("FromPtr");
+  auto ToPtrType = qualType(pointsTo(ToPointee)).bind("ToPtr");
+  Finder->addMatcher(
+      cStyleCastExpr(hasSourceExpression(hasType(FromPtrType)),
+                     hasType(ToPtrType),
+                     unless(hasAncestor(functionDecl(
+                         matchers::matchesAnyListedName(IgnoredFunctions)))))
+          .bind("CastExpr"),
+      this);
+}
+
+void CastToStructCheck::check(const MatchFinder::MatchResult &Result) {
+  const auto *const FoundCastExpr =
+      Result.Nodes.getNodeAs<CStyleCastExpr>("CastExpr");
+  const auto *const FromPtr = Result.Nodes.getNodeAs<QualType>("FromPtr");
+  const auto *const ToPtr = Result.Nodes.getNodeAs<QualType>("ToPtr");
+  const auto *const FromPointee =
+      Result.Nodes.getNodeAs<QualType>("FromPointee");
+  const auto *const ToPointee = Result.Nodes.getNodeAs<QualType>("ToPointee");
+  const auto *const FromType = Result.Nodes.getNodeAs<Type>("FromType");
+  const auto *const ToType = Result.Nodes.getNodeAs<RecordType>("ToType");
+  if (!FromPointee || !ToPointee)
+    return;
+  if (FromType->isVoidType() || FromType->isUnionType() ||
+      ToType->isUnionType())
----------------
vbvictor wrote:

Should be placed inside AST matchers for readability and speedup

https://github.com/llvm/llvm-project/pull/153428