[clang-tools-extra] r308020 - [clang-tidy] Add bugprone-suspicious-memset-usage check
Gabor Horvath via cfe-commits
cfe-commits at lists.llvm.org
Fri Jul 14 05:15:55 PDT 2017
Author: xazax
Date: Fri Jul 14 05:15:55 2017
New Revision: 308020
URL: http://llvm.org/viewvc/llvm-project?rev=308020&view=rev
Log:
[clang-tidy] Add bugprone-suspicious-memset-usage check
Created new module bugprone and placed the check in that.
Finds memset() calls with potential mistakes in their arguments.
Replaces and extends the existing google-runtime-memset-zero-length check.
Cases covered:
* Fill value is a character '0'. Integer 0 might have been intended.
* Fill value is out of char range and gets truncated.
* Byte count is zero. Potentially swapped with the fill value argument.
Patch by: Reka Nikolett Kovacs
Differential Revision: https://reviews.llvm.org/D32700
Added:
clang-tools-extra/trunk/clang-tidy/bugprone/
clang-tools-extra/trunk/clang-tidy/bugprone/BugproneTidyModule.cpp
clang-tools-extra/trunk/clang-tidy/bugprone/CMakeLists.txt
clang-tools-extra/trunk/clang-tidy/bugprone/SuspiciousMemsetUsageCheck.cpp
clang-tools-extra/trunk/clang-tidy/bugprone/SuspiciousMemsetUsageCheck.h
clang-tools-extra/trunk/docs/clang-tidy/checks/bugprone-suspicious-memset-usage.rst
clang-tools-extra/trunk/test/clang-tidy/bugprone-suspicious-memset-usage.cpp
Removed:
clang-tools-extra/trunk/clang-tidy/google/MemsetZeroLengthCheck.cpp
clang-tools-extra/trunk/clang-tidy/google/MemsetZeroLengthCheck.h
clang-tools-extra/trunk/docs/clang-tidy/checks/google-runtime-memset.rst
clang-tools-extra/trunk/test/clang-tidy/google-runtime-memset-zero-length.cpp
Modified:
clang-tools-extra/trunk/clang-tidy/CMakeLists.txt
clang-tools-extra/trunk/clang-tidy/google/CMakeLists.txt
clang-tools-extra/trunk/clang-tidy/google/GoogleTidyModule.cpp
clang-tools-extra/trunk/clang-tidy/tool/CMakeLists.txt
clang-tools-extra/trunk/clang-tidy/tool/ClangTidyMain.cpp
clang-tools-extra/trunk/docs/ReleaseNotes.rst
clang-tools-extra/trunk/docs/clang-tidy/checks/list.rst
clang-tools-extra/trunk/docs/clang-tidy/index.rst
Modified: clang-tools-extra/trunk/clang-tidy/CMakeLists.txt
URL: http://llvm.org/viewvc/llvm-project/clang-tools-extra/trunk/clang-tidy/CMakeLists.txt?rev=308020&r1=308019&r2=308020&view=diff
==============================================================================
--- clang-tools-extra/trunk/clang-tidy/CMakeLists.txt (original)
+++ clang-tools-extra/trunk/clang-tidy/CMakeLists.txt Fri Jul 14 05:15:55 2017
@@ -28,6 +28,7 @@ add_clang_library(clangTidy
add_subdirectory(android)
add_subdirectory(boost)
+add_subdirectory(bugprone)
add_subdirectory(cert)
add_subdirectory(cppcoreguidelines)
add_subdirectory(google)
Added: clang-tools-extra/trunk/clang-tidy/bugprone/BugproneTidyModule.cpp
URL: http://llvm.org/viewvc/llvm-project/clang-tools-extra/trunk/clang-tidy/bugprone/BugproneTidyModule.cpp?rev=308020&view=auto
==============================================================================
--- clang-tools-extra/trunk/clang-tidy/bugprone/BugproneTidyModule.cpp (added)
+++ clang-tools-extra/trunk/clang-tidy/bugprone/BugproneTidyModule.cpp Fri Jul 14 05:15:55 2017
@@ -0,0 +1,38 @@
+//===--- BugproneTidyModule.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 "../ClangTidy.h"
+#include "../ClangTidyModule.h"
+#include "../ClangTidyModuleRegistry.h"
+#include "SuspiciousMemsetUsageCheck.h"
+
+namespace clang {
+namespace tidy {
+namespace bugprone {
+
+class BugproneModule : public ClangTidyModule {
+public:
+ void addCheckFactories(ClangTidyCheckFactories &CheckFactories) override {
+ CheckFactories.registerCheck<SuspiciousMemsetUsageCheck>(
+ "bugprone-suspicious-memset-usage");
+ }
+};
+
+} // namespace bugprone
+
+// Register the BugproneTidyModule using this statically initialized variable.
+static ClangTidyModuleRegistry::Add<bugprone::BugproneModule>
+ X("bugprone-module", "Adds checks for bugprone code constructs.");
+
+// This anchor is used to force the linker to link in the generated object file
+// and thus register the BugproneModule.
+volatile int BugproneModuleAnchorSource = 0;
+
+} // namespace tidy
+} // namespace clang
Added: clang-tools-extra/trunk/clang-tidy/bugprone/CMakeLists.txt
URL: http://llvm.org/viewvc/llvm-project/clang-tools-extra/trunk/clang-tidy/bugprone/CMakeLists.txt?rev=308020&view=auto
==============================================================================
--- clang-tools-extra/trunk/clang-tidy/bugprone/CMakeLists.txt (added)
+++ clang-tools-extra/trunk/clang-tidy/bugprone/CMakeLists.txt Fri Jul 14 05:15:55 2017
@@ -0,0 +1,16 @@
+set(LLVM_LINK_COMPONENTS support)
+
+add_clang_library(clangTidyBugproneModule
+ BugproneTidyModule.cpp
+ SuspiciousMemsetUsageCheck.cpp
+
+ LINK_LIBS
+ clangAnalysis
+ clangAST
+ clangASTMatchers
+ clangBasic
+ clangLex
+ clangTidy
+ clangTidyUtils
+ clangTooling
+ )
Added: clang-tools-extra/trunk/clang-tidy/bugprone/SuspiciousMemsetUsageCheck.cpp
URL: http://llvm.org/viewvc/llvm-project/clang-tools-extra/trunk/clang-tidy/bugprone/SuspiciousMemsetUsageCheck.cpp?rev=308020&view=auto
==============================================================================
--- clang-tools-extra/trunk/clang-tidy/bugprone/SuspiciousMemsetUsageCheck.cpp (added)
+++ clang-tools-extra/trunk/clang-tidy/bugprone/SuspiciousMemsetUsageCheck.cpp Fri Jul 14 05:15:55 2017
@@ -0,0 +1,127 @@
+//===--- SuspiciousMemsetUsageCheck.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 "SuspiciousMemsetUsageCheck.h"
+#include "clang/AST/ASTContext.h"
+#include "clang/ASTMatchers/ASTMatchFinder.h"
+#include "clang/ASTMatchers/ASTMatchers.h"
+#include "clang/Lex/Lexer.h"
+#include "clang/Tooling/FixIt.h"
+
+using namespace clang::ast_matchers;
+
+namespace clang {
+namespace tidy {
+namespace bugprone {
+
+void SuspiciousMemsetUsageCheck::registerMatchers(MatchFinder *Finder) {
+ // Note: void *memset(void *buffer, int fill_char, size_t byte_count);
+ // Look for memset(x, '0', z). Probably memset(x, 0, z) was intended.
+ Finder->addMatcher(
+ callExpr(
+ callee(functionDecl(hasName("::memset"))),
+ hasArgument(1, characterLiteral(equals(static_cast<unsigned>('0')))
+ .bind("char-zero-fill")),
+ unless(
+ eachOf(hasArgument(0, anyOf(hasType(pointsTo(isAnyCharacter())),
+ hasType(arrayType(hasElementType(
+ isAnyCharacter()))))),
+ isInTemplateInstantiation()))),
+ this);
+
+ // Look for memset with an integer literal in its fill_char argument.
+ // Will check if it gets truncated.
+ Finder->addMatcher(callExpr(callee(functionDecl(hasName("::memset"))),
+ hasArgument(1, integerLiteral().bind("num-fill")),
+ unless(isInTemplateInstantiation())),
+ this);
+
+ // Look for memset(x, y, 0) as that is most likely an argument swap.
+ Finder->addMatcher(
+ callExpr(callee(functionDecl(hasName("::memset"))),
+ unless(hasArgument(1, anyOf(characterLiteral(equals(
+ static_cast<unsigned>('0'))),
+ integerLiteral()))),
+ unless(isInTemplateInstantiation()))
+ .bind("call"),
+ this);
+}
+
+void SuspiciousMemsetUsageCheck::check(const MatchFinder::MatchResult &Result) {
+ if (const auto *CharZeroFill =
+ Result.Nodes.getNodeAs<CharacterLiteral>("char-zero-fill")) {
+ // Case 1: fill_char of memset() is a character '0'. Probably an
+ // integer zero was intended.
+
+ SourceRange CharRange = CharZeroFill->getSourceRange();
+ auto Diag =
+ diag(CharZeroFill->getLocStart(), "memset fill value is char '0', "
+ "potentially mistaken for int 0");
+
+ // Only suggest a fix if no macros are involved.
+ if (CharRange.getBegin().isMacroID())
+ return;
+ Diag << FixItHint::CreateReplacement(
+ CharSourceRange::getTokenRange(CharRange), "0");
+ }
+
+ else if (const auto *NumFill =
+ Result.Nodes.getNodeAs<IntegerLiteral>("num-fill")) {
+ // Case 2: fill_char of memset() is larger in size than an unsigned char
+ // so it gets truncated during conversion.
+
+ llvm::APSInt NumValue;
+ const auto UCharMax = (1 << Result.Context->getCharWidth()) - 1;
+ if (!NumFill->EvaluateAsInt(NumValue, *Result.Context) ||
+ (NumValue >= 0 && NumValue <= UCharMax))
+ return;
+
+ diag(NumFill->getLocStart(), "memset fill value is out of unsigned "
+ "character range, gets truncated");
+ }
+
+ else if (const auto *Call = Result.Nodes.getNodeAs<CallExpr>("call")) {
+ // Case 3: byte_count of memset() is zero. This is most likely an
+ // argument swap.
+
+ const Expr *FillChar = Call->getArg(1);
+ const Expr *ByteCount = Call->getArg(2);
+
+ // Return if `byte_count` is not zero at compile time.
+ llvm::APSInt Value1, Value2;
+ if (ByteCount->isValueDependent() ||
+ !ByteCount->EvaluateAsInt(Value2, *Result.Context) || Value2 != 0)
+ return;
+
+ // Return if `fill_char` is known to be zero or negative at compile
+ // time. In these cases, swapping the args would be a nop, or
+ // introduce a definite bug. The code is likely correct.
+ if (!FillChar->isValueDependent() &&
+ FillChar->EvaluateAsInt(Value1, *Result.Context) &&
+ (Value1 == 0 || Value1.isNegative()))
+ return;
+
+ // `byte_count` is known to be zero at compile time, and `fill_char` is
+ // either not known or known to be a positive integer. Emit a warning
+ // and fix-its to swap the arguments.
+ auto D = diag(Call->getLocStart(),
+ "memset of size zero, potentially swapped arguments");
+ StringRef RHSString = tooling::fixit::getText(*ByteCount, *Result.Context);
+ StringRef LHSString = tooling::fixit::getText(*FillChar, *Result.Context);
+ if (LHSString.empty() || RHSString.empty())
+ return;
+
+ D << tooling::fixit::createReplacement(*FillChar, RHSString)
+ << tooling::fixit::createReplacement(*ByteCount, LHSString);
+ }
+}
+
+} // namespace bugprone
+} // namespace tidy
+} // namespace clang
Added: clang-tools-extra/trunk/clang-tidy/bugprone/SuspiciousMemsetUsageCheck.h
URL: http://llvm.org/viewvc/llvm-project/clang-tools-extra/trunk/clang-tidy/bugprone/SuspiciousMemsetUsageCheck.h?rev=308020&view=auto
==============================================================================
--- clang-tools-extra/trunk/clang-tidy/bugprone/SuspiciousMemsetUsageCheck.h (added)
+++ clang-tools-extra/trunk/clang-tidy/bugprone/SuspiciousMemsetUsageCheck.h Fri Jul 14 05:15:55 2017
@@ -0,0 +1,35 @@
+//===--- SuspiciousMemsetUsageCheck.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_BUGPRONE_SUSPICIOUS_MEMSET_USAGE_H
+#define LLVM_CLANG_TOOLS_EXTRA_CLANG_TIDY_BUGPRONE_SUSPICIOUS_MEMSET_USAGE_H
+
+#include "../ClangTidy.h"
+
+namespace clang {
+namespace tidy {
+namespace bugprone {
+
+/// Finds memset calls with potential mistakes in their arguments.
+///
+/// For the user-facing documentation see:
+/// http://clang.llvm.org/extra/clang-tidy/checks/bugprone-suspicious-memset-usage.html
+class SuspiciousMemsetUsageCheck : public ClangTidyCheck {
+public:
+ SuspiciousMemsetUsageCheck(StringRef Name, ClangTidyContext *Context)
+ : ClangTidyCheck(Name, Context) {}
+ void registerMatchers(ast_matchers::MatchFinder *Finder) override;
+ void check(const ast_matchers::MatchFinder::MatchResult &Result) override;
+};
+
+} // namespace bugprone
+} // namespace tidy
+} // namespace clang
+
+#endif // LLVM_CLANG_TOOLS_EXTRA_CLANG_TIDY_BUGPRONE_SUSPICIOUS_MEMSET_USAGE_H
Modified: clang-tools-extra/trunk/clang-tidy/google/CMakeLists.txt
URL: http://llvm.org/viewvc/llvm-project/clang-tools-extra/trunk/clang-tidy/google/CMakeLists.txt?rev=308020&r1=308019&r2=308020&view=diff
==============================================================================
--- clang-tools-extra/trunk/clang-tidy/google/CMakeLists.txt (original)
+++ clang-tools-extra/trunk/clang-tidy/google/CMakeLists.txt Fri Jul 14 05:15:55 2017
@@ -8,7 +8,6 @@ add_clang_library(clangTidyGoogleModule
GlobalNamesInHeadersCheck.cpp
GoogleTidyModule.cpp
IntegerTypesCheck.cpp
- MemsetZeroLengthCheck.cpp
NonConstReferences.cpp
OverloadedUnaryAndCheck.cpp
StringReferenceMemberCheck.cpp
Modified: clang-tools-extra/trunk/clang-tidy/google/GoogleTidyModule.cpp
URL: http://llvm.org/viewvc/llvm-project/clang-tools-extra/trunk/clang-tidy/google/GoogleTidyModule.cpp?rev=308020&r1=308019&r2=308020&view=diff
==============================================================================
--- clang-tools-extra/trunk/clang-tidy/google/GoogleTidyModule.cpp (original)
+++ clang-tools-extra/trunk/clang-tidy/google/GoogleTidyModule.cpp Fri Jul 14 05:15:55 2017
@@ -20,7 +20,6 @@
#include "ExplicitMakePairCheck.h"
#include "GlobalNamesInHeadersCheck.h"
#include "IntegerTypesCheck.h"
-#include "MemsetZeroLengthCheck.h"
#include "NonConstReferences.h"
#include "OverloadedUnaryAndCheck.h"
#include "StringReferenceMemberCheck.h"
@@ -55,8 +54,6 @@ public:
"google-runtime-references");
CheckFactories.registerCheck<runtime::StringReferenceMemberCheck>(
"google-runtime-member-string-references");
- CheckFactories.registerCheck<runtime::MemsetZeroLengthCheck>(
- "google-runtime-memset");
CheckFactories.registerCheck<readability::AvoidCStyleCastsCheck>(
"google-readability-casting");
CheckFactories.registerCheck<readability::TodoCommentCheck>(
Removed: clang-tools-extra/trunk/clang-tidy/google/MemsetZeroLengthCheck.cpp
URL: http://llvm.org/viewvc/llvm-project/clang-tools-extra/trunk/clang-tidy/google/MemsetZeroLengthCheck.cpp?rev=308019&view=auto
==============================================================================
--- clang-tools-extra/trunk/clang-tidy/google/MemsetZeroLengthCheck.cpp (original)
+++ clang-tools-extra/trunk/clang-tidy/google/MemsetZeroLengthCheck.cpp (removed)
@@ -1,96 +0,0 @@
-//===--- MemsetZeroLengthCheck.cpp - clang-tidy -------------------*- C++ -*-===//
-//
-// The LLVM Compiler Infrastructure
-//
-// This file is distributed under the University of Illinois Open Source
-// License. See LICENSE.TXT for details.
-//
-//===----------------------------------------------------------------------===//
-
-#include "MemsetZeroLengthCheck.h"
-#include "clang/AST/ASTContext.h"
-#include "clang/ASTMatchers/ASTMatchFinder.h"
-#include "clang/ASTMatchers/ASTMatchers.h"
-#include "clang/Lex/Lexer.h"
-
-using namespace clang::ast_matchers;
-
-namespace clang {
-namespace tidy {
-namespace google {
-namespace runtime {
-
-void MemsetZeroLengthCheck::registerMatchers(
- ast_matchers::MatchFinder *Finder) {
- // Look for memset(x, y, 0) as those is most likely an argument swap.
- // TODO: Also handle other standard functions that suffer from the same
- // problem, e.g. memchr.
- Finder->addMatcher(callExpr(callee(functionDecl(hasName("::memset"))),
- argumentCountIs(3),
- unless(isInTemplateInstantiation()))
- .bind("decl"),
- this);
-}
-
-/// \brief Get a StringRef representing a SourceRange.
-static StringRef getAsString(const MatchFinder::MatchResult &Result,
- SourceRange R) {
- const SourceManager &SM = *Result.SourceManager;
- // Don't even try to resolve macro or include contraptions. Not worth emitting
- // a fixit for.
- if (R.getBegin().isMacroID() ||
- !SM.isWrittenInSameFile(R.getBegin(), R.getEnd()))
- return StringRef();
-
- const char *Begin = SM.getCharacterData(R.getBegin());
- const char *End = SM.getCharacterData(Lexer::getLocForEndOfToken(
- R.getEnd(), 0, SM, Result.Context->getLangOpts()));
-
- return StringRef(Begin, End - Begin);
-}
-
-void MemsetZeroLengthCheck::check(const MatchFinder::MatchResult &Result) {
- const auto *Call = Result.Nodes.getNodeAs<CallExpr>("decl");
-
- // Note, this is:
- // void *memset(void *buffer, int fill_char, size_t byte_count);
- // Arg1 is fill_char, Arg2 is byte_count.
- const Expr *Arg1 = Call->getArg(1);
- const Expr *Arg2 = Call->getArg(2);
-
- // Return if `byte_count` is not zero at compile time.
- llvm::APSInt Value1, Value2;
- if (Arg2->isValueDependent() ||
- !Arg2->EvaluateAsInt(Value2, *Result.Context) || Value2 != 0)
- return;
-
- // Return if `fill_char` is known to be zero or negative at compile
- // time. In these cases, swapping the args would be a nop, or
- // introduce a definite bug. The code is likely correct.
- if (!Arg1->isValueDependent() &&
- Arg1->EvaluateAsInt(Value1, *Result.Context) &&
- (Value1 == 0 || Value1.isNegative()))
- return;
-
- // `byte_count` is known to be zero at compile time, and `fill_char` is
- // either not known or known to be a positive integer. Emit a warning
- // and fix-its to swap the arguments.
- auto D = diag(Call->getLocStart(),
- "memset of size zero, potentially swapped arguments");
- SourceRange LHSRange = Arg1->getSourceRange();
- SourceRange RHSRange = Arg2->getSourceRange();
- StringRef RHSString = getAsString(Result, RHSRange);
- StringRef LHSString = getAsString(Result, LHSRange);
- if (LHSString.empty() || RHSString.empty())
- return;
-
- D << FixItHint::CreateReplacement(CharSourceRange::getTokenRange(LHSRange),
- RHSString)
- << FixItHint::CreateReplacement(CharSourceRange::getTokenRange(RHSRange),
- LHSString);
-}
-
-} // namespace runtime
-} // namespace google
-} // namespace tidy
-} // namespace clang
Removed: clang-tools-extra/trunk/clang-tidy/google/MemsetZeroLengthCheck.h
URL: http://llvm.org/viewvc/llvm-project/clang-tools-extra/trunk/clang-tidy/google/MemsetZeroLengthCheck.h?rev=308019&view=auto
==============================================================================
--- clang-tools-extra/trunk/clang-tidy/google/MemsetZeroLengthCheck.h (original)
+++ clang-tools-extra/trunk/clang-tidy/google/MemsetZeroLengthCheck.h (removed)
@@ -1,39 +0,0 @@
-//===--- MemsetZeroLengthCheck.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_GOOGLE_MEMSETZEROLENGTHCHECK_H
-#define LLVM_CLANG_TOOLS_EXTRA_CLANG_TIDY_GOOGLE_MEMSETZEROLENGTHCHECK_H
-
-#include "../ClangTidy.h"
-
-namespace clang {
-namespace tidy {
-namespace google {
-namespace runtime {
-
-/// Finds calls to memset with a literal zero in the length argument.
-///
-/// This is most likely unintended and the length and value arguments are
-/// swapped.
-///
-/// Corresponding cpplint.py check name: 'runtime/memset'.
-class MemsetZeroLengthCheck : public ClangTidyCheck {
-public:
- MemsetZeroLengthCheck(StringRef Name, ClangTidyContext *Context)
- : ClangTidyCheck(Name, Context) {}
- void registerMatchers(ast_matchers::MatchFinder *Finder) override;
- void check(const ast_matchers::MatchFinder::MatchResult &Result) override;
-};
-
-} // namespace runtime
-} // namespace google
-} // namespace tidy
-} // namespace clang
-
-#endif // LLVM_CLANG_TOOLS_EXTRA_CLANG_TIDY_GOOGLE_MEMSETZEROLENGTHCHECK_H
Modified: clang-tools-extra/trunk/clang-tidy/tool/CMakeLists.txt
URL: http://llvm.org/viewvc/llvm-project/clang-tools-extra/trunk/clang-tidy/tool/CMakeLists.txt?rev=308020&r1=308019&r2=308020&view=diff
==============================================================================
--- clang-tools-extra/trunk/clang-tidy/tool/CMakeLists.txt (original)
+++ clang-tools-extra/trunk/clang-tidy/tool/CMakeLists.txt Fri Jul 14 05:15:55 2017
@@ -15,6 +15,7 @@ target_link_libraries(clang-tidy
clangTidy
clangTidyAndroidModule
clangTidyBoostModule
+ clangTidyBugproneModule
clangTidyCERTModule
clangTidyCppCoreGuidelinesModule
clangTidyGoogleModule
Modified: clang-tools-extra/trunk/clang-tidy/tool/ClangTidyMain.cpp
URL: http://llvm.org/viewvc/llvm-project/clang-tools-extra/trunk/clang-tidy/tool/ClangTidyMain.cpp?rev=308020&r1=308019&r2=308020&view=diff
==============================================================================
--- clang-tools-extra/trunk/clang-tidy/tool/ClangTidyMain.cpp (original)
+++ clang-tools-extra/trunk/clang-tidy/tool/ClangTidyMain.cpp Fri Jul 14 05:15:55 2017
@@ -462,6 +462,11 @@ extern volatile int BoostModuleAnchorSou
static int LLVM_ATTRIBUTE_UNUSED BoostModuleAnchorDestination =
BoostModuleAnchorSource;
+// This anchor is used to force the linker to link the BugproneModule.
+extern volatile int BugproneModuleAnchorSource;
+static int LLVM_ATTRIBUTE_UNUSED BugproneModuleAnchorDestination =
+ BugproneModuleAnchorSource;
+
// This anchor is used to force the linker to link the LLVMModule.
extern volatile int LLVMModuleAnchorSource;
static int LLVM_ATTRIBUTE_UNUSED LLVMModuleAnchorDestination =
Modified: clang-tools-extra/trunk/docs/ReleaseNotes.rst
URL: http://llvm.org/viewvc/llvm-project/clang-tools-extra/trunk/docs/ReleaseNotes.rst?rev=308020&r1=308019&r2=308020&view=diff
==============================================================================
--- clang-tools-extra/trunk/docs/ReleaseNotes.rst (original)
+++ clang-tools-extra/trunk/docs/ReleaseNotes.rst Fri Jul 14 05:15:55 2017
@@ -79,6 +79,12 @@ Improvements to clang-tidy
Checks if the required file flag ``SOCK_CLOEXEC`` is present in the argument of
``socket()``.
+- New `bugprone-suspicious-memset-usage
+ <http://clang.llvm.org/extra/clang-tidy/checks/bugprone-suspicious-memset-usage.html>`_ check
+
+ Finds ``memset()`` calls with potential mistakes in their arguments.
+ Replaces and extends the ``google-runtime-memset`` check.
+
- New `cert-dcl21-cpp
<http://clang.llvm.org/extra/clang-tidy/checks/cert-dcl21-cpp.html>`_ check
@@ -157,6 +163,10 @@ Improvements to clang-tidy
- Support clang-formatting of the code around applied fixes (``-format-style``
command-line option).
+- New `bugprone` module
+
+ Adds checks that target bugprone code constructs.
+
- New `hicpp` module
Adds checks that implement the `High Integrity C++ Coding Standard <http://www.codingstandard.com/section/index/>`_ and other safety
Added: clang-tools-extra/trunk/docs/clang-tidy/checks/bugprone-suspicious-memset-usage.rst
URL: http://llvm.org/viewvc/llvm-project/clang-tools-extra/trunk/docs/clang-tidy/checks/bugprone-suspicious-memset-usage.rst?rev=308020&view=auto
==============================================================================
--- clang-tools-extra/trunk/docs/clang-tidy/checks/bugprone-suspicious-memset-usage.rst (added)
+++ clang-tools-extra/trunk/docs/clang-tidy/checks/bugprone-suspicious-memset-usage.rst Fri Jul 14 05:15:55 2017
@@ -0,0 +1,54 @@
+.. title:: clang-tidy - bugprone-suspicious-memset-usage
+
+bugprone-suspicious-memset-usage
+================================
+
+This check finds ``memset()`` calls with potential mistakes in their arguments.
+Considering the function as ``void* memset(void* destination, int fill_value,
+size_t byte_count)``, the following cases are covered:
+
+**Case 1: Fill value is a character ``'0'``**
+
+Filling up a memory area with ASCII code 48 characters is not customary,
+possibly integer zeroes were intended instead.
+The check offers a replacement of ``'0'`` with ``0``. Memsetting character
+pointers with ``'0'`` is allowed.
+
+**Case 2: Fill value is truncated**
+
+Memset converts ``fill_value`` to ``unsigned char`` before using it. If
+``fill_value`` is out of unsigned character range, it gets truncated
+and memory will not contain the desired pattern.
+
+**Case 3: Byte count is zero**
+
+Calling memset with a literal zero in its ``byte_count`` argument is likely
+to be unintended and swapped with ``fill_value``. The check offers to swap
+these two arguments.
+
+Corresponding cpplint.py check name: ``runtime/memset``.
+
+
+Examples:
+
+.. code-block:: c++
+
+ void foo() {
+ int i[5] = {1, 2, 3, 4, 5};
+ int *ip = i;
+ char c = '1';
+ char *cp = &c;
+ int v = 0;
+
+ // Case 1
+ memset(ip, '0', 1); // suspicious
+ memset(cp, '0', 1); // OK
+
+ // Case 2
+ memset(ip, 0xabcd, 1); // fill value gets truncated
+ memset(ip, 0x00, 1); // OK
+
+ // Case 3
+ memset(ip, sizeof(int), v); // zero length, potentially swapped
+ memset(ip, 0, 1); // OK
+ }
Removed: clang-tools-extra/trunk/docs/clang-tidy/checks/google-runtime-memset.rst
URL: http://llvm.org/viewvc/llvm-project/clang-tools-extra/trunk/docs/clang-tidy/checks/google-runtime-memset.rst?rev=308019&view=auto
==============================================================================
--- clang-tools-extra/trunk/docs/clang-tidy/checks/google-runtime-memset.rst (original)
+++ clang-tools-extra/trunk/docs/clang-tidy/checks/google-runtime-memset.rst (removed)
@@ -1,10 +0,0 @@
-.. title:: clang-tidy - google-runtime-memset
-
-google-runtime-memset
-=====================
-
-Finds calls to ``memset`` with a literal zero in the length argument.
-
-This is most likely unintended and the length and value arguments are swapped.
-
-Corresponding cpplint.py check name: `runtime/memset`.
Modified: clang-tools-extra/trunk/docs/clang-tidy/checks/list.rst
URL: http://llvm.org/viewvc/llvm-project/clang-tools-extra/trunk/docs/clang-tidy/checks/list.rst?rev=308020&r1=308019&r2=308020&view=diff
==============================================================================
--- clang-tools-extra/trunk/docs/clang-tidy/checks/list.rst (original)
+++ clang-tools-extra/trunk/docs/clang-tidy/checks/list.rst Fri Jul 14 05:15:55 2017
@@ -9,6 +9,7 @@ Clang-Tidy Checks
android-cloexec-open
android-cloexec-socket
boost-use-to-string
+ bugprone-suspicious-memset-usage
cert-dcl03-c (redirects to misc-static-assert) <cert-dcl03-c>
cert-dcl21-cpp
cert-dcl50-cpp
@@ -55,7 +56,6 @@ Clang-Tidy Checks
google-readability-todo
google-runtime-int
google-runtime-member-string-references
- google-runtime-memset
google-runtime-operator
google-runtime-references
hicpp-explicit-conversions
Modified: clang-tools-extra/trunk/docs/clang-tidy/index.rst
URL: http://llvm.org/viewvc/llvm-project/clang-tools-extra/trunk/docs/clang-tidy/index.rst?rev=308020&r1=308019&r2=308020&view=diff
==============================================================================
--- clang-tools-extra/trunk/docs/clang-tidy/index.rst (original)
+++ clang-tools-extra/trunk/docs/clang-tidy/index.rst Fri Jul 14 05:15:55 2017
@@ -57,6 +57,7 @@ Name prefix Description
====================== =========================================================
``android-`` Checks related to Android.
``boost-`` Checks related to Boost library.
+``bugprone-`` Checks that target bugprone code constructs.
``cert-`` Checks related to CERT Secure Coding Guidelines.
``cppcoreguidelines-`` Checks related to C++ Core Guidelines.
``clang-analyzer-`` Clang Static Analyzer checks.
Added: clang-tools-extra/trunk/test/clang-tidy/bugprone-suspicious-memset-usage.cpp
URL: http://llvm.org/viewvc/llvm-project/clang-tools-extra/trunk/test/clang-tidy/bugprone-suspicious-memset-usage.cpp?rev=308020&view=auto
==============================================================================
--- clang-tools-extra/trunk/test/clang-tidy/bugprone-suspicious-memset-usage.cpp (added)
+++ clang-tools-extra/trunk/test/clang-tidy/bugprone-suspicious-memset-usage.cpp Fri Jul 14 05:15:55 2017
@@ -0,0 +1,77 @@
+// RUN: %check_clang_tidy %s bugprone-suspicious-memset-usage %t
+
+void *memset(void *, int, __SIZE_TYPE__);
+
+namespace std {
+ using ::memset;
+}
+
+template <typename T>
+void mtempl(int *ptr) {
+ memset(ptr, '0', sizeof(T));
+// CHECK-MESSAGES: :[[@LINE-1]]:15: warning: memset fill value is char '0', potentially mistaken for int 0 [bugprone-suspicious-memset-usage]
+// CHECK-FIXES: memset(ptr, 0, sizeof(T));
+ memset(ptr, 256, sizeof(T));
+// CHECK-MESSAGES: :[[@LINE-1]]:15: warning: memset fill value is out of unsigned character range, gets truncated [bugprone-suspicious-memset-usage]
+ memset(0, sizeof(T), 0);
+// CHECK-MESSAGES: :[[@LINE-1]]:3: warning: memset of size zero, potentially swapped arguments [bugprone-suspicious-memset-usage]
+// CHECK-FIXES: memset(0, 0, sizeof(T));
+ memset(0, sizeof(int), 0);
+// CHECK-MESSAGES: :[[@LINE-1]]:3: warning: memset of size zero, potentially swapped arguments [bugprone-suspicious-memset-usage]
+// CHECK-FIXES: memset(0, 0, sizeof(int));
+}
+
+void foo(int xsize, int ysize) {
+ int i[5] = {1, 2, 3, 4, 5};
+ char ca[3] = {'a', 'b', 'c'};
+ int *p = i;
+ int l = 5;
+ char z = '1';
+ char *c = &z;
+ int v = 0;
+
+ memset(p, '0', l);
+// CHECK-MESSAGES: :[[@LINE-1]]:13: warning: memset fill value is char '0', potentially mistaken for int 0 [bugprone-suspicious-memset-usage]
+// CHECK-FIXES: memset(p, 0, l);
+
+ memset(p, 0xabcd, l);
+// CHECK-MESSAGES: :[[@LINE-1]]:13: warning: memset fill value is out of unsigned character range, gets truncated [bugprone-suspicious-memset-usage]
+
+ memset(p, sizeof(int), 0);
+// CHECK-MESSAGES: :[[@LINE-1]]:3: warning: memset of size zero, potentially swapped arguments [bugprone-suspicious-memset-usage]
+// CHECK-FIXES: memset(p, 0, sizeof(int));
+ std::memset(p, sizeof(int), 0x00);
+// CHECK-MESSAGES: :[[@LINE-1]]:3: warning: memset of size zero, potentially swapped arguments [bugprone-suspicious-memset-usage]
+// CHECK-FIXES: std::memset(p, 0x00, sizeof(int));
+
+#define M_CHAR_ZERO memset(p, '0', l);
+ M_CHAR_ZERO
+// CHECK-MESSAGES: :[[@LINE-1]]:3: warning: memset fill value is char '0', potentially mistaken for int 0 [bugprone-suspicious-memset-usage]
+
+#define M_OUTSIDE_RANGE memset(p, 0xabcd, l);
+ M_OUTSIDE_RANGE
+// CHECK-MESSAGES: :[[@LINE-1]]:3: warning: memset fill value is out of unsigned character range, gets truncated [bugprone-suspicious-memset-usage]
+
+#define M_ZERO_LENGTH memset(p, sizeof(int), 0);
+ M_ZERO_LENGTH
+// CHECK-MESSAGES: :[[@LINE-1]]:3: warning: memset of size zero, potentially swapped arguments [bugprone-suspicious-memset-usage]
+
+ memset(p, '2', l);
+ memset(p, 0, l);
+ memset(c, '0', 1);
+ memset(ca, '0', sizeof(ca));
+
+ memset(p, 0x00, l);
+ mtempl<int>(p);
+
+ memset(p, sizeof(int), v + 1);
+ memset(p, 0xcd, 1);
+
+ // Don't warn when the fill char and the length are both known to be
+ // zero. No bug is possible.
+ memset(p, 0, v);
+
+ // -1 is clearly not a length by virtue of being negative, so no warning
+ // despite v == 0.
+ memset(p, -1, v);
+}
Removed: clang-tools-extra/trunk/test/clang-tidy/google-runtime-memset-zero-length.cpp
URL: http://llvm.org/viewvc/llvm-project/clang-tools-extra/trunk/test/clang-tidy/google-runtime-memset-zero-length.cpp?rev=308019&view=auto
==============================================================================
--- clang-tools-extra/trunk/test/clang-tidy/google-runtime-memset-zero-length.cpp (original)
+++ clang-tools-extra/trunk/test/clang-tidy/google-runtime-memset-zero-length.cpp (removed)
@@ -1,62 +0,0 @@
-// RUN: %check_clang_tidy %s google-runtime-memset %t
-
-void *memset(void *, int, __SIZE_TYPE__);
-
-namespace std {
- using ::memset;
-}
-
-template <int i, typename T>
-void memtmpl() {
- memset(0, sizeof(int), i);
- memset(0, sizeof(T), sizeof(T));
- memset(0, sizeof(T), 0);
-// CHECK-MESSAGES: :[[@LINE-1]]:3: warning: memset of size zero, potentially swapped argument
-// CHECK-FIXES: memset(0, 0, sizeof(T));
- memset(0, sizeof(int), 0);
-// CHECK-MESSAGES: :[[@LINE-1]]:3: warning: memset of size zero, potentially swapped argument
-// CHECK-FIXES: memset(0, 0, sizeof(int));
-}
-
-void foo(void *a, int xsize, int ysize) {
- memset(a, sizeof(int), 0);
-// CHECK-MESSAGES: :[[@LINE-1]]:3: warning: memset of size zero, potentially swapped argument
-// CHECK-FIXES: memset(a, 0, sizeof(int));
-#define M memset(a, sizeof(int), 0);
- M
-// CHECK-MESSAGES: :[[@LINE-1]]:3: warning: memset of size zero, potentially swapped argument
-// CHECK-FIXES: #define M memset(a, sizeof(int), 0);
- ::memset(a, xsize *
- ysize, 0);
-// CHECK-MESSAGES: :[[@LINE-2]]:3: warning: memset of size zero, potentially swapped argument
-// CHECK-FIXES: ::memset(a, 0, xsize *
-// CHECK-FIXES-NEXT: ysize);
- std::memset(a, sizeof(int), 0x00);
-// CHECK-MESSAGES: :[[@LINE-1]]:3: warning: memset of size zero, potentially swapped argument
-// CHECK-FIXES: std::memset(a, 0x00, sizeof(int));
-
- const int v = 0;
- memset(a, sizeof(int), v);
-// CHECK-MESSAGES: :[[@LINE-1]]:3: warning: memset of size zero, potentially swapped argument
-// CHECK-FIXES: memset(a, v, sizeof(int));
-
- memset(a, sizeof(int), v + v);
-// CHECK-MESSAGES: :[[@LINE-1]]:3: warning: memset of size zero, potentially swapped argument
-// CHECK-FIXES: memset(a, v + v, sizeof(int));
-
- memset(a, sizeof(int), v + 1);
-
- memset(a, -1, sizeof(int));
- memset(a, 0xcd, 1);
-
- // Don't warn when the fill char and the length are both known to be
- // zero. No bug is possible.
- memset(a, 0, v);
- memset(a, v, 0);
-
- // -1 is clearly not a length by virtue of being negative, so no warning
- // despite v == 0.
- memset(a, -1, v);
-
- memtmpl<0, int>();
-}
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