From dc48412c938f39d51b8980db9f957cab30af671e Mon Sep 17 00:00:00 2001 From: Matthias Gehre Date: Mon, 12 Oct 2015 21:53:19 +0000 Subject: [clang-tidy] new check cppcoreguidelines-pro-bounds-pointer-arithmetic Summary: This check flags all usage of pointer arithmetic, because it could lead to an invalid pointer. Subtraction of two pointers is not flagged by this check. Pointers should only refer to single objects, and pointer arithmetic is fragile and easy to get wrong. array_view is a bounds-checked, safe type for accessing arrays of data. This rule is part of the "Bounds safety" profile of the C++ Core Guidelines, see https://github.com/isocpp/CppCoreGuidelines/blob/master/CppCoreGuidelines.md#-bounds1-dont-use-pointer-arithmetic-use-array_view-instead Depends on D13313 Subscribers: cfe-commits Differential Revision: http://reviews.llvm.org/D13311 llvm-svn: 250116 --- .../clang-tidy/cppcoreguidelines/CMakeLists.txt | 1 + .../CppCoreGuidelinesTidyModule.cpp | 3 ++ .../ProBoundsPointerArithmeticCheck.cpp | 53 ++++++++++++++++++++++ .../ProBoundsPointerArithmeticCheck.h | 34 ++++++++++++++ 4 files changed, 91 insertions(+) create mode 100644 clang-tools-extra/clang-tidy/cppcoreguidelines/ProBoundsPointerArithmeticCheck.cpp create mode 100644 clang-tools-extra/clang-tidy/cppcoreguidelines/ProBoundsPointerArithmeticCheck.h (limited to 'clang-tools-extra/clang-tidy/cppcoreguidelines') diff --git a/clang-tools-extra/clang-tidy/cppcoreguidelines/CMakeLists.txt b/clang-tools-extra/clang-tidy/cppcoreguidelines/CMakeLists.txt index d35b9a56f94..6147914a9fe 100644 --- a/clang-tools-extra/clang-tidy/cppcoreguidelines/CMakeLists.txt +++ b/clang-tools-extra/clang-tidy/cppcoreguidelines/CMakeLists.txt @@ -2,6 +2,7 @@ set(LLVM_LINK_COMPONENTS support) add_clang_library(clangTidyCppCoreGuidelinesModule CppCoreGuidelinesTidyModule.cpp + ProBoundsPointerArithmeticCheck.cpp ProTypeConstCastCheck.cpp ProTypeReinterpretCastCheck.cpp ProTypeStaticCastDowncastCheck.cpp diff --git a/clang-tools-extra/clang-tidy/cppcoreguidelines/CppCoreGuidelinesTidyModule.cpp b/clang-tools-extra/clang-tidy/cppcoreguidelines/CppCoreGuidelinesTidyModule.cpp index 358bd6ec8fd..07ba15a8b4a 100644 --- a/clang-tools-extra/clang-tidy/cppcoreguidelines/CppCoreGuidelinesTidyModule.cpp +++ b/clang-tools-extra/clang-tidy/cppcoreguidelines/CppCoreGuidelinesTidyModule.cpp @@ -10,6 +10,7 @@ #include "../ClangTidy.h" #include "../ClangTidyModule.h" #include "../ClangTidyModuleRegistry.h" +#include "ProBoundsPointerArithmeticCheck.h" #include "ProTypeConstCastCheck.h" #include "ProTypeReinterpretCastCheck.h" #include "ProTypeStaticCastDowncastCheck.h" @@ -22,6 +23,8 @@ namespace cppcoreguidelines { class CppCoreGuidelinesModule : public ClangTidyModule { public: void addCheckFactories(ClangTidyCheckFactories &CheckFactories) override { + CheckFactories.registerCheck( + "cppcoreguidelines-pro-bounds-pointer-arithmetic"); CheckFactories.registerCheck( "cppcoreguidelines-pro-type-const-cast"); CheckFactories.registerCheck( diff --git a/clang-tools-extra/clang-tidy/cppcoreguidelines/ProBoundsPointerArithmeticCheck.cpp b/clang-tools-extra/clang-tidy/cppcoreguidelines/ProBoundsPointerArithmeticCheck.cpp new file mode 100644 index 00000000000..15ea27a4462 --- /dev/null +++ b/clang-tools-extra/clang-tidy/cppcoreguidelines/ProBoundsPointerArithmeticCheck.cpp @@ -0,0 +1,53 @@ +//===--- ProBoundsPointerArithmeticCheck.cpp - clang-tidy------------------===// +// +// The LLVM Compiler Infrastructure +// +// This file is distributed under the University of Illinois Open Source +// License. See LICENSE.TXT for details. +// +//===----------------------------------------------------------------------===// + +#include "ProBoundsPointerArithmeticCheck.h" +#include "clang/AST/ASTContext.h" +#include "clang/ASTMatchers/ASTMatchFinder.h" + +using namespace clang::ast_matchers; + +namespace clang { +namespace tidy { + +void ProBoundsPointerArithmeticCheck::registerMatchers(MatchFinder *Finder) { + if (!getLangOpts().CPlusPlus) + return; + + // Flag all operators +, -, +=, -=, ++, -- that result in a pointer + Finder->addMatcher( + binaryOperator(anyOf(hasOperatorName("+"), hasOperatorName("-"), + hasOperatorName("+="), hasOperatorName("-=")), + hasType(pointerType())) + .bind("expr"), + this); + + Finder->addMatcher( + unaryOperator(anyOf(hasOperatorName("++"), hasOperatorName("--")), + hasType(pointerType())) + .bind("expr"), + this); + + // Array subscript on a pointer (not an array) is also pointer arithmetic + Finder->addMatcher( + arraySubscriptExpr(hasBase(ignoringImpCasts(anyOf(hasType(pointerType()), + hasType(decayedType(hasDecayedType(pointerType()))))))) + .bind("expr"), + this); +} + +void +ProBoundsPointerArithmeticCheck::check(const MatchFinder::MatchResult &Result) { + const auto *MatchedExpr = Result.Nodes.getNodeAs("expr"); + + diag(MatchedExpr->getExprLoc(), "do not use pointer arithmetic"); +} + +} // namespace tidy +} // namespace clang diff --git a/clang-tools-extra/clang-tidy/cppcoreguidelines/ProBoundsPointerArithmeticCheck.h b/clang-tools-extra/clang-tidy/cppcoreguidelines/ProBoundsPointerArithmeticCheck.h new file mode 100644 index 00000000000..f3a3fb18cff --- /dev/null +++ b/clang-tools-extra/clang-tidy/cppcoreguidelines/ProBoundsPointerArithmeticCheck.h @@ -0,0 +1,34 @@ +//===--- ProBoundsPointerArithmeticCheck.h - clang-tidy----------*- C++ -*-===// +// +// The LLVM Compiler Infrastructure +// +// This file is distributed under the University of Illinois Open Source +// License. See LICENSE.TXT for details. +// +//===----------------------------------------------------------------------===// + +#ifndef LLVM_CLANG_TOOLS_EXTRA_CLANG_TIDY_CPPCOREGUIDELINES_PRO_BOUNDS_POINTER_ARITHMETIC_H +#define LLVM_CLANG_TOOLS_EXTRA_CLANG_TIDY_CPPCOREGUIDELINES_PRO_BOUNDS_POINTER_ARITHMETIC_H + +#include "../ClangTidy.h" + +namespace clang { +namespace tidy { + +/// Flags all kinds of pointer arithmetic that have result of pointer type, i.e. +/// +, -, +=, -=, ++, --. In addition, the [] operator on pointers (not on arrays) is flagged. +/// +/// For the user-facing documentation see: +/// http://clang.llvm.org/extra/clang-tidy/checks/cppcoreguidelines-pro-bounds-pointer-arithmetic.html +class ProBoundsPointerArithmeticCheck : public ClangTidyCheck { +public: + ProBoundsPointerArithmeticCheck(StringRef Name, ClangTidyContext *Context) + : ClangTidyCheck(Name, Context) {} + void registerMatchers(ast_matchers::MatchFinder *Finder) override; + void check(const ast_matchers::MatchFinder::MatchResult &Result) override; +}; + +} // namespace tidy +} // namespace clang + +#endif // LLVM_CLANG_TOOLS_EXTRA_CLANG_TIDY_CPPCOREGUIDELINES_PRO_BOUNDS_POINTER_ARITHMETIC_H -- cgit v1.2.3