[clang-tools-extra] [clang-tidy] Add bugprone-smart-ptr-initialization check (PR #181570)

[Baranov Victor via cfe-commits]

================
@@ -0,0 +1,160 @@
+//===----------------------------------------------------------------------===//
+//
+// 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 "SmartPtrInitializationCheck.h"
+#include "../utils/OptionsUtils.h"
+#include "clang/AST/ASTContext.h"
+#include "clang/AST/DeclCXX.h"
+#include "clang/ASTMatchers/ASTMatchFinder.h"
+#include "clang/ASTMatchers/ASTMatchers.h"
+
+using namespace clang::ast_matchers;
+
+namespace clang::tidy::bugprone {
+
+namespace {
+
+const auto DefaultSharedPointers = "::std::shared_ptr;::boost::shared_ptr";
+const auto DefaultUniquePointers = "::std::unique_ptr";
+const auto DefaultDefaultDeleters = "::std::default_delete";
+
+} // namespace
+
+SmartPtrInitializationCheck::SmartPtrInitializationCheck(
+    StringRef Name, ClangTidyContext *Context)
+    : ClangTidyCheck(Name, Context),
+      SharedPointers(utils::options::parseStringList(
+          Options.get("SharedPointers", DefaultSharedPointers))),
+      UniquePointers(utils::options::parseStringList(
+          Options.get("UniquePointers", DefaultUniquePointers))),
+      DefaultDeleters(utils::options::parseStringList(
+          Options.get("DefaultDeleters", DefaultDefaultDeleters))) {}
+
+void SmartPtrInitializationCheck::storeOptions(
+    ClangTidyOptions::OptionMap &Opts) {
+  Options.store(Opts, "SharedPointers",
+                utils::options::serializeStringList(SharedPointers));
+  Options.store(Opts, "UniquePointers",
+                utils::options::serializeStringList(UniquePointers));
+  Options.store(Opts, "DefaultDeleters",
+                utils::options::serializeStringList(DefaultDeleters));
+}
+
+void SmartPtrInitializationCheck::registerMatchers(MatchFinder *Finder) {
+  const auto IsSharedPtr = hasAnyName(SharedPointers);
+  const auto IsUniquePtr = hasAnyName(UniquePointers);
+  const auto IsSmartPtr = anyOf(IsSharedPtr, IsUniquePtr);
+  const auto IsDefaultDeleter = hasAnyName(DefaultDeleters);
+
+  const auto IsSharedPtrRecord = cxxRecordDecl(IsSharedPtr);
+  const auto IsUniquePtrRecord = cxxRecordDecl(IsUniquePtr);
+  const auto IsSmartPtrRecord = cxxRecordDecl(IsSmartPtr);
+
+  auto ReleaseMethod = cxxMethodDecl(hasName("release"));
+  auto ResetMethod = cxxMethodDecl(hasName("reset"));
+
+  auto ReleaseCallMatcher = cxxMemberCallExpr(callee(ReleaseMethod));
+
+  // Array automatically decays to pointer
+  auto PointerArg = expr(anyOf(hasType(pointerType()), hasType(arrayType())))
+                        .bind("pointer-arg");
+
+  // Matcher for unique_ptr types with custom deleters
+  auto UniquePtrWithCustomDeleter = classTemplateSpecializationDecl(
+      IsUniquePtr, templateArgumentCountIs(2),
+      hasTemplateArgument(
+          1, refersToType(
+                 unless(hasUnqualifiedDesugaredType(recordType(hasDeclaration(
+                     classTemplateSpecializationDecl(IsDefaultDeleter))))))));
+
+  // Matcher for smart pointer constructors
+  // Exclude constructors with custom deleters:
+  // - shared_ptr with 2+ arguments (second is deleter)
+  // - unique_ptr with 2+ template args where second is not default_delete
+  auto HasCustomDeleter = anyOf(
+      allOf(hasDeclaration(cxxConstructorDecl(ofClass(IsSharedPtrRecord))),
+            hasArgument(1, anything())),
+      allOf(hasType(hasUnqualifiedDesugaredType(
+                recordType(hasDeclaration(UniquePtrWithCustomDeleter)))),
+            hasDeclaration(cxxConstructorDecl(ofClass(IsUniquePtrRecord)))));
+
+  auto SmartPtrConstructorMatcher =
+      cxxConstructExpr(
+          hasDeclaration(cxxConstructorDecl(ofClass(IsSmartPtrRecord))),
+          hasArgument(0, PointerArg), unless(HasCustomDeleter),
+          unless(hasArgument(0, cxxNewExpr())),
+          unless(hasArgument(0, ReleaseCallMatcher)))
+          .bind("constructor");
+
+  // Matcher for reset() calls
+  // Exclude reset() calls with custom deleters:
+  // - shared_ptr with 2+ arguments (second is deleter)
+  // - unique_ptr with custom deleter type (2+ template args where second is not
+  // default_delete)
+  auto HasCustomDeleterInReset = anyOf(
+      allOf(on(hasType(hasUnqualifiedDesugaredType(recordType(hasDeclaration(
+                classTemplateSpecializationDecl(IsSharedPtr)))))),
+            hasArgument(1, anything())),
+      on(hasType(hasUnqualifiedDesugaredType(
+          recordType(hasDeclaration(UniquePtrWithCustomDeleter))))));
+
+  auto ResetCallMatcher =
+      cxxMemberCallExpr(
+          on(hasType(hasUnqualifiedDesugaredType(recordType(
+              hasDeclaration(classTemplateSpecializationDecl(IsSmartPtr)))))),
+          callee(ResetMethod), hasArgument(0, PointerArg),
+          unless(HasCustomDeleterInReset), unless(hasArgument(0, cxxNewExpr())),
+          unless(hasArgument(0, ReleaseCallMatcher)))
+          .bind("reset-call");
+
+  Finder->addMatcher(SmartPtrConstructorMatcher, this);
+  Finder->addMatcher(ResetCallMatcher, this);
+}
+
+void SmartPtrInitializationCheck::check(
+    const MatchFinder::MatchResult &Result) {
+  const auto *PointerArg = Result.Nodes.getNodeAs<Expr>("pointer-arg");
+  const auto *Constructor =
+      Result.Nodes.getNodeAs<CXXConstructExpr>("constructor");
+  const auto *ResetCall =
+      Result.Nodes.getNodeAs<CXXMemberCallExpr>("reset-call");
+  assert(PointerArg);
+
+  const SourceLocation Loc = PointerArg->getBeginLoc();
+  const CXXMethodDecl *MethodDecl =
+      Constructor ? Constructor->getConstructor()
+                  : (ResetCall ? ResetCall->getMethodDecl() : nullptr);
+  if (!MethodDecl)
+    return;
+
+  const auto *Record = MethodDecl->getParent();
+  if (!Record)
+    return;
+
+  const std::string TypeName = Record->getQualifiedNameAsString();
+  diag(Loc, "passing a raw pointer '%0' to %1%2 may cause double deletion")
+      << getPointerDescription(PointerArg, *Result.Context) << TypeName
+      << (Constructor ? " constructor" : "::reset()");
+}
+
+std::string
+SmartPtrInitializationCheck::getPointerDescription(const Expr *PointerExpr,
+                                                   ASTContext &Context) {
+  std::string Description;
+  llvm::raw_string_ostream OS(Description);
+
+  // Try to get a readable representation of the expression
+  PrintingPolicy Policy(Context.getLangOpts());
+  Policy.SuppressSpecifiers = false;
+  Policy.SuppressTagKeyword = true;
+
+  PointerExpr->printPretty(OS, nullptr, Policy);
+  return OS.str();
+}
----------------
vbvictor wrote:

Why is this needed, we should print whole type.
If we are in templates, we need full type

https://github.com/llvm/llvm-project/pull/181570