| //===--- 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" |
| #include "clang/ASTMatchers/ASTMatchers.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 GlobalVariable = varDecl( |
| hasGlobalStorage(), |
| unless(anyOf( |
| isLocalVarDecl(), isConstexpr(), hasType(isConstQualified()), |
| hasType(referenceType())))); // References can't be changed, only the |
| // data they reference can be changed. |
| |
| auto GlobalReferenceToNonConst = |
| varDecl(hasGlobalStorage(), hasType(referenceType()), |
| unless(hasType(references(qualType(isConstQualified()))))); |
| |
| auto GlobalPointerToNonConst = |
| varDecl(hasGlobalStorage(), |
| hasType(pointerType(pointee(unless(isConstQualified()))))); |
| |
| Finder->addMatcher(GlobalVariable.bind("non-const_variable"), this); |
| Finder->addMatcher(GlobalReferenceToNonConst.bind("indirection_to_non-const"), |
| this); |
| Finder->addMatcher(GlobalPointerToNonConst.bind("indirection_to_non-const"), |
| this); |
| } |
| |
| void AvoidNonConstGlobalVariablesCheck::check( |
| const MatchFinder::MatchResult &Result) { |
| |
| if (const auto *Variable = |
| Result.Nodes.getNodeAs<VarDecl>("non-const_variable")) { |
| diag(Variable->getLocation(), "variable %0 is non-const and globally " |
| "accessible, consider making it const") |
| << Variable; // FIXME: Add fix-it hint to Variable |
| // Don't return early, a non-const variable may also be a pointer or |
| // reference to non-const data. |
| } |
| |
| if (const auto *VD = |
| Result.Nodes.getNodeAs<VarDecl>("indirection_to_non-const")) { |
| diag(VD->getLocation(), |
| "variable %0 provides global access to a non-const object; consider " |
| "making the %select{referenced|pointed-to}1 data 'const'") |
| << VD |
| << VD->getType()->isPointerType(); // FIXME: Add fix-it hint to Variable |
| } |
| } |
| |
| } // namespace cppcoreguidelines |
| } // namespace tidy |
| } // namespace clang |