1 files changed, 113 insertions, 0 deletions
diff --git a/compilerplugins/clang/trivialdestructor.cxx b/compilerplugins/clang/trivialdestructor.cxx
new file mode 100644
index 000000000..5db1bbab7
--- /dev/null
+++ b/compilerplugins/clang/trivialdestructor.cxx
@@ -0,0 +1,113 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/*
+ * This file is part of the LibreOffice project.
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ */
+
+#include <cassert>
+#include <string>
+#include <iostream>
+#include <unordered_map>
+#include <unordered_set>
+
+#include "plugin.hxx"
+#include "check.hxx"
+#include "config_clang.h"
+#include "clang/AST/CXXInheritance.h"
+#include "clang/AST/StmtVisitor.h"
+
+// Look for explicit destructors that can be trivial (and therefore don't need to be declared)
+
+namespace
+{
+class TrivialDestructor : public loplugin::FilteringPlugin<TrivialDestructor>
+{
+public:
+    explicit TrivialDestructor(loplugin::InstantiationData const& data)
+        : FilteringPlugin(data)
+    {
+    }
+
+    virtual void run() override { TraverseDecl(compiler.getASTContext().getTranslationUnitDecl()); }
+
+    bool VisitCXXDestructorDecl(CXXDestructorDecl const*);
+
+private:
+    bool HasTrivialDestructorBody(const CXXRecordDecl* ClassDecl);
+    bool FieldHasTrivialDestructor(const FieldDecl* Field);
+};
+
+bool TrivialDestructor::VisitCXXDestructorDecl(CXXDestructorDecl const* destructorDecl)
+{
+    if (ignoreLocation(destructorDecl))
+        return true;
+    if (!destructorDecl->isThisDeclarationADefinition())
+        return true;
+    if (!destructorDecl->hasTrivialBody())
+        return true;
+    if (destructorDecl->isVirtual())
+        return true;
+    if (destructorDecl->getExceptionSpecType() != EST_None)
+        return true;
+    if (destructorDecl->getAccess() != AS_public)
+        return true;
+    if (isInUnoIncludeFile(
+            compiler.getSourceManager().getSpellingLoc(destructorDecl->getLocation())))
+        return true;
+    if (!HasTrivialDestructorBody(destructorDecl->getParent()))
+        return true;
+
+    report(DiagnosticsEngine::Warning, "no need for explicit destructor decl",
+           destructorDecl->getLocation())
+        << destructorDecl->getSourceRange();
+    for (FunctionDecl const* d2 = destructorDecl;;)
+    {
+        d2 = d2->getPreviousDecl();
+        if (d2 == nullptr)
+        {
+            break;
+        }
+        report(DiagnosticsEngine::Note, "previous declaration is here", d2->getLocation())
+            << d2->getSourceRange();
+    }
+    return true;
+}
+
+bool TrivialDestructor::HasTrivialDestructorBody(const CXXRecordDecl* ClassDecl)
+{
+    // Check fields.
+    for (const auto* field : ClassDecl->fields())
+        if (!FieldHasTrivialDestructor(field))
+            return false;
+
+    // Check bases.
+    for (const auto& I : ClassDecl->bases())
+    {
+        const CXXRecordDecl* Base = I.getType()->getAsCXXRecordDecl();
+        if (!Base->hasTrivialDestructor())
+            return false;
+    }
+
+    return true;
+}
+
+bool TrivialDestructor::FieldHasTrivialDestructor(const FieldDecl* Field)
+{
+    QualType FieldBaseElementType = compiler.getASTContext().getBaseElementType(Field->getType());
+
+    const RecordType* RT = FieldBaseElementType->getAs<RecordType>();
+    if (!RT)
+        return true;
+
+    CXXRecordDecl* FieldClassDecl = cast<CXXRecordDecl>(RT->getDecl());
+
+    return FieldClassDecl->hasTrivialDestructor();
+}
+
+loplugin::Plugin::Registration<TrivialDestructor> X("trivialdestructor", true);
+}
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */