From 5f3c2204eb7dbe82cc64bf0ade34ecfb4b9ffc05 Mon Sep 17 00:00:00 2001 From: Stephan Bergmann Date: Wed, 28 Aug 2019 11:17:20 +0200 Subject: New loplugin:stdfunction ...finding dubious additions to namespace std (concentrating on functions for now). C++17 [namespace.std]/1: "The behavior of a C ++ program is undefined if it adds declarations or definitions to namespace std or to a namespace within namespace std unless otherwise specified." This found ad4c7b97752b4da73808402604d6f96b39d920f5 "Avoid declaring function templates in namespace std" 042e30a3dc057aef4a02d95960e4dd4fb8d083ae "Avoid adding a function template declaration to namespace std" cae9240a76cdb0eeed92421930d3b4cbef0ac201 "Avoid adding a function declaration to namespace std" Change-Id: Ic2ba54e2a8bf931d5c58cedf499c0d1229eb2166 Reviewed-on: https://gerrit.libreoffice.org/78220 Tested-by: Jenkins Reviewed-by: Stephan Bergmann --- compilerplugins/clang/check.cxx | 37 +++++++++++++++++--- compilerplugins/clang/check.hxx | 13 +++---- compilerplugins/clang/stdfunction.cxx | 48 +++++++++++++++++++++++++ compilerplugins/clang/test/stdfunction.cxx | 56 ++++++++++++++++++++++++++++++ 4 files changed, 141 insertions(+), 13 deletions(-) create mode 100644 compilerplugins/clang/stdfunction.cxx create mode 100644 compilerplugins/clang/test/stdfunction.cxx (limited to 'compilerplugins') diff --git a/compilerplugins/clang/check.cxx b/compilerplugins/clang/check.cxx index f2443e44a1f2..d53bfabbe9cf 100644 --- a/compilerplugins/clang/check.cxx +++ b/compilerplugins/clang/check.cxx @@ -151,12 +151,17 @@ ContextCheck DeclCheck::MemberFunction() const { return ContextCheck(m == nullptr ? nullptr : m->getParent()); } +namespace { + +bool isGlobalNamespace(clang::DeclContext const * context) { + assert(context != nullptr); + return (context->isLookupContext() ? context : context->getLookupParent())->isTranslationUnit(); +} + +} + TerminalCheck ContextCheck::GlobalNamespace() const { - return TerminalCheck( - context_ != nullptr - && ((context_->isLookupContext() - ? context_ : context_->getLookupParent()) - ->isTranslationUnit())); + return TerminalCheck(context_ != nullptr && isGlobalNamespace(context_)); } TerminalCheck ContextCheck::StdNamespace() const { @@ -164,6 +169,28 @@ TerminalCheck ContextCheck::StdNamespace() const { context_ != nullptr && context_->isStdNamespace()); } +namespace { + +bool isStdOrNestedNamespace(clang::DeclContext const * context) { + assert(context != nullptr); + if (!context->isNamespace()) { + return false; + } + if (isGlobalNamespace(context)) { + return false; + } + if (context->isStdNamespace()) { + return true; + } + return isStdOrNestedNamespace(context->getParent()); +} + +} + +TerminalCheck ContextCheck::StdOrNestedNamespace() const { + return TerminalCheck(context_ != nullptr && isStdOrNestedNamespace(context_)); +} + ContextCheck ContextCheck::AnonymousNamespace() const { auto n = llvm::dyn_cast_or_null(context_); return ContextCheck( diff --git a/compilerplugins/clang/check.hxx b/compilerplugins/clang/check.hxx index 0904e5f2f1a1..4ac4f8e99cb6 100644 --- a/compilerplugins/clang/check.hxx +++ b/compilerplugins/clang/check.hxx @@ -103,6 +103,9 @@ private: class ContextCheck { public: + explicit ContextCheck(clang::DeclContext const * context = nullptr): + context_(context) {} + explicit operator bool() const { return context_ != nullptr; } TerminalCheck GlobalNamespace() const; @@ -111,6 +114,8 @@ public: TerminalCheck StdNamespace() const; + TerminalCheck StdOrNestedNamespace() const; + ContextCheck AnonymousNamespace() const; inline ContextCheck Class(llvm::StringRef id) const; @@ -120,14 +125,6 @@ public: explicit ContextCheck(const clang::NamespaceDecl * decl ) : context_( decl ) {} private: - friend DeclCheck; - friend TypeCheck; - friend ContextCheck detail::checkRecordDecl( - clang::Decl const * decl, clang::TagTypeKind tag, llvm::StringRef id); - - explicit ContextCheck(clang::DeclContext const * context = nullptr): - context_(context) {} - clang::DeclContext const * const context_; }; diff --git a/compilerplugins/clang/stdfunction.cxx b/compilerplugins/clang/stdfunction.cxx new file mode 100644 index 000000000000..89935558d8a2 --- /dev/null +++ b/compilerplugins/clang/stdfunction.cxx @@ -0,0 +1,48 @@ +/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4; fill-column: 100 -*- */ +/* + * 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 "check.hxx" +#include "plugin.hxx" + +namespace +{ +class StdFunction final : public loplugin::FilteringPlugin +{ +public: + explicit StdFunction(loplugin::InstantiationData const& data) + : FilteringPlugin(data) + { + } + + bool VisitFunctionDecl(FunctionDecl const* decl) + { + if (ignoreLocation(decl)) + { + return true; + } + if (!loplugin::ContextCheck(decl->getDeclContext()).StdOrNestedNamespace()) + { + return true; + } + report(DiagnosticsEngine::Warning, + ("Do not declare a %select{function|function template|member function template" + " specialization|function template specialization}0 in namespace 'std'"), + decl->getLocation()) + << decl->getTemplatedKind() << decl->getSourceRange(); + return true; + } + +private: + void run() override { TraverseDecl(compiler.getASTContext().getTranslationUnitDecl()); } +}; + +static loplugin::Plugin::Registration X("stdfunction"); +} + +/* vim:set shiftwidth=4 softtabstop=4 expandtab cinoptions=b1,g0,N-s cinkeys+=0=break: */ diff --git a/compilerplugins/clang/test/stdfunction.cxx b/compilerplugins/clang/test/stdfunction.cxx new file mode 100644 index 000000000000..492ba4249f16 --- /dev/null +++ b/compilerplugins/clang/test/stdfunction.cxx @@ -0,0 +1,56 @@ +/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4; fill-column: 100 -*- */ +/* + * 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 +#include + +struct S +{ + bool empty() const; +}; + +template struct ST +{ + bool empty() const; +}; + +namespace std +{ +bool empty( //expected-error {{Do not declare a function in namespace 'std' [loplugin:stdfunction]}} + S const&); + +template <> +bool empty( //expected-error {{Do not declare a function template specialization in namespace 'std' [loplugin:stdfunction]}} + S const&); + +template +bool empty( //expected-error {{Do not declare a function template in namespace 'std' [loplugin:stdfunction]}} + ST const&); + +template <> class vector +{ +public: + [[nodiscard]] constexpr bool empty() const noexcept; +}; + +[[nodiscard]] constexpr bool vector::empty() const noexcept { return true; } +} + +namespace std::inner +{ +bool empty( //expected-error {{Do not declare a function in namespace 'std' [loplugin:stdfunction]}} + S const&); +} + +namespace outer::std +{ +bool empty(S const&); +} + +/* vim:set shiftwidth=4 softtabstop=4 expandtab cinoptions=b1,g0,N-s cinkeys+=0=break: */ -- cgit