vingeldal created this revision.
vingeldal added reviewers: JonasToth, aaron.ballman.
Herald added subscribers: kbarton, xazax.hun, mgorny, nemanjai.
Herald added a project: clang.
Cpp Core Guideline I.2, a.k.a "Avoid non-const global variables"
For detailed documentation, see:
https://github.com/isocpp/CppCoreGuidelines/blob/master/CppCoreGuidelines.md#i2-avoid-non-const-global-variables
Repository:
rG LLVM Github Monorepo
https://reviews.llvm.org/D70265
Files:
clang-tools-extra/clang-tidy/cppcoreguidelines/AvoidNonConstGlobalVariablesCheck.cpp
clang-tools-extra/clang-tidy/cppcoreguidelines/AvoidNonConstGlobalVariablesCheck.h
clang-tools-extra/clang-tidy/cppcoreguidelines/CMakeLists.txt
clang-tools-extra/clang-tidy/cppcoreguidelines/CppCoreGuidelinesTidyModule.cpp
clang-tools-extra/docs/ReleaseNotes.rst
clang-tools-extra/docs/clang-tidy/checks/cppcoreguidelines-avoid-non-const-global-variables.rst
clang-tools-extra/docs/clang-tidy/checks/list.rst
clang-tools-extra/test/clang-tidy/checkers/cppcoreguidelines-avoid-non-const-global-variables.cpp
Index: clang-tools-extra/test/clang-tidy/checkers/cppcoreguidelines-avoid-non-const-global-variables.cpp
===================================================================
--- /dev/null
+++ clang-tools-extra/test/clang-tidy/checkers/cppcoreguidelines-avoid-non-const-global-variables.cpp
@@ -0,0 +1,35 @@
+// RUN: %check_clang_tidy %s cppcoreguidelines-avoid-non-const-global-variables %t
+
+int nonConstVariable = 0;
+// CHECK-MESSAGES: warning: variable 'nonConstVariable' is non-const and global [cppcoreguidelines-avoid-non-const-global-variables]
+// CHECK-FIXES: int const nonConstVariable = 0;
+
+namespace namespace_name {
+int nonConstNamespaceVariable = 0;
+// CHECK-MESSAGES: warning: variable 'nonConstNamespaceVariable' is non-const and global [cppcoreguidelines-avoid-non-const-global-variables]
+// CHECK-FIXES: int const nonConstNamespaceVariable = 0;
+} // namespace namespace_name
+
+const int constVariable = 0;
+
+constexpr int constexprVariable = 0;
+
+int function() {
+ int nonConstReturnValue = 0;
+ return nonConstReturnValue;
+}
+
+namespace {
+int nonConstAnonymousNamespaceVariable = 0;
+}
+
+class Class {
+ int nonConstMemberVariable = 0;
+};
+
+int main() {
+ for (int i = 0; i < 10; ++i) {
+ int nonConstLoopVariable = 42;
+ nonConstVariable = nonConstLoopVariable + i;
+ }
+}
\ No newline at end of file
Index: clang-tools-extra/docs/clang-tidy/checks/list.rst
===================================================================
--- clang-tools-extra/docs/clang-tidy/checks/list.rst
+++ clang-tools-extra/docs/clang-tidy/checks/list.rst
@@ -194,6 +194,7 @@
cppcoreguidelines-avoid-c-arrays (redirects to modernize-avoid-c-arrays) <cppcoreguidelines-avoid-c-arrays>
cppcoreguidelines-avoid-goto
cppcoreguidelines-avoid-magic-numbers (redirects to readability-magic-numbers) <cppcoreguidelines-avoid-magic-numbers>
+ cppcoreguidelines-avoid-non-const-global-variables
cppcoreguidelines-c-copy-assignment-signature (redirects to misc-unconventional-assign-operator) <cppcoreguidelines-c-copy-assignment-signature>
cppcoreguidelines-explicit-virtual-functions (redirects to modernize-use-override) <cppcoreguidelines-explicit-virtual-functions>
cppcoreguidelines-init-variables
Index: clang-tools-extra/docs/clang-tidy/checks/cppcoreguidelines-avoid-non-const-global-variables.rst
===================================================================
--- /dev/null
+++ clang-tools-extra/docs/clang-tidy/checks/cppcoreguidelines-avoid-non-const-global-variables.rst
@@ -0,0 +1,6 @@
+.. title:: clang-tidy - cppcoreguidelines-avoid-non-const-global-variables
+
+cppcoreguidelines-avoid-non-const-global-variables
+==================================================
+
+FIXME: Describe what patterns does the check detect and why. Give examples.
Index: clang-tools-extra/docs/ReleaseNotes.rst
===================================================================
--- clang-tools-extra/docs/ReleaseNotes.rst
+++ clang-tools-extra/docs/ReleaseNotes.rst
@@ -94,6 +94,9 @@
Without the null terminator it can result in undefined behaviour when the
string is read.
+- New :doc:`cppcoreguidelines-avoid-non-const-global-variables
+ <clang-tidy/checks/cppcoreguidelines-avoid-non-const-global-variables>` check.
+
- New alias :doc:`cert-pos44-c
<clang-tidy/checks/cert-pos44-c>` to
:doc:`bugprone-bad-signal-to-kill-thread
Index: clang-tools-extra/clang-tidy/cppcoreguidelines/CppCoreGuidelinesTidyModule.cpp
===================================================================
--- clang-tools-extra/clang-tidy/cppcoreguidelines/CppCoreGuidelinesTidyModule.cpp
+++ clang-tools-extra/clang-tidy/cppcoreguidelines/CppCoreGuidelinesTidyModule.cpp
@@ -15,6 +15,7 @@
#include "../modernize/UseOverrideCheck.h"
#include "../readability/MagicNumbersCheck.h"
#include "AvoidGotoCheck.h"
+#include "AvoidNonConstGlobalVariablesCheck.h"
#include "InitVariablesCheck.h"
#include "InterfacesGlobalInitCheck.h"
#include "MacroUsageCheck.h"
@@ -48,6 +49,8 @@
"cppcoreguidelines-avoid-goto");
CheckFactories.registerCheck<readability::MagicNumbersCheck>(
"cppcoreguidelines-avoid-magic-numbers");
+ CheckFactories.registerCheck<AvoidNonConstGlobalVariablesCheck>(
+ "cppcoreguidelines-avoid-non-const-global-variables");
CheckFactories.registerCheck<modernize::UseOverrideCheck>(
"cppcoreguidelines-explicit-virtual-functions");
CheckFactories.registerCheck<InitVariablesCheck>(
Index: clang-tools-extra/clang-tidy/cppcoreguidelines/CMakeLists.txt
===================================================================
--- clang-tools-extra/clang-tidy/cppcoreguidelines/CMakeLists.txt
+++ clang-tools-extra/clang-tidy/cppcoreguidelines/CMakeLists.txt
@@ -2,6 +2,7 @@
add_clang_library(clangTidyCppCoreGuidelinesModule
AvoidGotoCheck.cpp
+ AvoidNonConstGlobalVariablesCheck.cpp
CppCoreGuidelinesTidyModule.cpp
InitVariablesCheck.cpp
InterfacesGlobalInitCheck.cpp
Index: clang-tools-extra/clang-tidy/cppcoreguidelines/AvoidNonConstGlobalVariablesCheck.h
===================================================================
--- /dev/null
+++ clang-tools-extra/clang-tidy/cppcoreguidelines/AvoidNonConstGlobalVariablesCheck.h
@@ -0,0 +1,35 @@
+//===--- AvoidNonConstGlobalVariablesCheck.h - clang-tidy -------*- C++ -*-===//
+//
+// 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
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_CLANG_TOOLS_EXTRA_CLANG_TIDY_CPPCOREGUIDELINES_AVOIDNONCONSTGLOBALVARIABLESCHECK_H
+#define LLVM_CLANG_TOOLS_EXTRA_CLANG_TIDY_CPPCOREGUIDELINES_AVOIDNONCONSTGLOBALVARIABLESCHECK_H
+
+#include "../ClangTidyCheck.h"
+
+namespace clang {
+namespace tidy {
+namespace cppcoreguidelines {
+
+/// Non-const global variables hide dependencies and make the dependencies
+/// subject to unpredictable changes.
+///
+/// For the user-facing documentation see:
+/// http://clang.llvm.org/extra/clang-tidy/checks/cppcoreguidelines-avoid-non-const-global-variables.html
+class AvoidNonConstGlobalVariablesCheck : public ClangTidyCheck {
+public:
+ AvoidNonConstGlobalVariablesCheck(StringRef Name, ClangTidyContext *Context)
+ : ClangTidyCheck(Name, Context) {}
+ void registerMatchers(ast_matchers::MatchFinder *Finder) override;
+ void check(const ast_matchers::MatchFinder::MatchResult &Result) override;
+};
+
+} // namespace cppcoreguidelines
+} // namespace tidy
+} // namespace clang
+
+#endif // LLVM_CLANG_TOOLS_EXTRA_CLANG_TIDY_CPPCOREGUIDELINES_AVOIDNONCONSTGLOBALVARIABLESCHECK_H
Index: clang-tools-extra/clang-tidy/cppcoreguidelines/AvoidNonConstGlobalVariablesCheck.cpp
===================================================================
--- /dev/null
+++ clang-tools-extra/clang-tidy/cppcoreguidelines/AvoidNonConstGlobalVariablesCheck.cpp
@@ -0,0 +1,45 @@
+//===--- AvoidNonConstGlobalVariablesCheck.cpp - clang-tidy ---------------===//
+//
+// 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 "AvoidNonConstGlobalVariablesCheck.h"
+#include "clang/AST/ASTContext.h"
+#include "clang/ASTMatchers/ASTMatchFinder.h"
+
+using namespace clang::ast_matchers;
+
+namespace clang {
+namespace tidy {
+namespace cppcoreguidelines {
+
+namespace {
+AST_MATCHER(VarDecl, isLocalVarDecl) { return Node.isLocalVarDecl(); }
+} // namespace
+
+void AvoidNonConstGlobalVariablesCheck::registerMatchers(MatchFinder *Finder) {
+ auto loop = stmt(anyOf(forStmt(), cxxForRangeStmt(), whileStmt(), doStmt()));
+ Finder->addMatcher(varDecl(unless(isLocalVarDecl()),
+ unless(hasAncestor(namespaceDecl(isAnonymous()))),
+ unless(isConstexpr()),
+ unless(hasType(isConstQualified())))
+ .bind("non-const"),
+ this);
+}
+
+void AvoidNonConstGlobalVariablesCheck::check(
+ const MatchFinder::MatchResult &Result) {
+ const auto *MatchedDecl = Result.Nodes.getNodeAs<VarDecl>("non-const");
+
+ diag(MatchedDecl->getLocation(), "variable %0 is non-const and global")
+ << MatchedDecl;
+ diag(MatchedDecl->getLocation(), "insert 'const '", DiagnosticIDs::Note)
+ << FixItHint::CreateInsertion(MatchedDecl->getLocation(), "const ");
+}
+
+} // namespace cppcoreguidelines
+} // namespace tidy
+} // namespace clang
_______________________________________________
cfe-commits mailing list
cfe-commits@lists.llvm.org
https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
