|
| 1 | +//===--- InitVariablesCheck.cpp - clang-tidy ------------------------------===// |
| 2 | +// |
| 3 | +// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. |
| 4 | +// See https://llvm.org/LICENSE.txt for license information. |
| 5 | +// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception |
| 6 | +// |
| 7 | +//===----------------------------------------------------------------------===// |
| 8 | + |
| 9 | +#include "InitVariablesCheck.h" |
| 10 | + |
| 11 | +#include "clang/AST/ASTContext.h" |
| 12 | +#include "clang/ASTMatchers/ASTMatchFinder.h" |
| 13 | + |
| 14 | +using namespace clang::ast_matchers; |
| 15 | + |
| 16 | +namespace clang { |
| 17 | +namespace tidy { |
| 18 | +namespace cppcoreguidelines { |
| 19 | + |
| 20 | +namespace { |
| 21 | +AST_MATCHER(VarDecl, isLocalVarDecl) { return Node.isLocalVarDecl(); } |
| 22 | +} // namespace |
| 23 | + |
| 24 | +InitVariablesCheck::InitVariablesCheck(StringRef Name, |
| 25 | + ClangTidyContext *Context) |
| 26 | + : ClangTidyCheck(Name, Context), |
| 27 | + IncludeStyle(utils::IncludeSorter::parseIncludeStyle( |
| 28 | + Options.getLocalOrGlobal("IncludeStyle", "llvm"))), |
| 29 | + MathHeader(Options.get("MathHeader", "math.h")) {} |
| 30 | + |
| 31 | +void InitVariablesCheck::registerMatchers(MatchFinder *Finder) { |
| 32 | + Finder->addMatcher(varDecl(unless(hasInitializer(anything())), |
| 33 | + unless(isInstantiated()), isLocalVarDecl(), |
| 34 | + unless(isStaticLocal()), isDefinition()) |
| 35 | + .bind("vardecl"), |
| 36 | + this); |
| 37 | +} |
| 38 | + |
| 39 | +void InitVariablesCheck::registerPPCallbacks(const SourceManager &SM, |
| 40 | + Preprocessor *PP, |
| 41 | + Preprocessor *ModuleExpanderPP) { |
| 42 | + IncludeInserter = |
| 43 | + std::make_unique<utils::IncludeInserter>(SM, getLangOpts(), IncludeStyle); |
| 44 | + PP->addPPCallbacks(IncludeInserter->CreatePPCallbacks()); |
| 45 | +} |
| 46 | + |
| 47 | +void InitVariablesCheck::check(const MatchFinder::MatchResult &Result) { |
| 48 | + const auto *MatchedDecl = Result.Nodes.getNodeAs<VarDecl>("vardecl"); |
| 49 | + const ASTContext &Context = *Result.Context; |
| 50 | + const SourceManager &Source = Context.getSourceManager(); |
| 51 | + |
| 52 | + // We want to warn about cases where the type name |
| 53 | + // comes from a macro like this: |
| 54 | + // |
| 55 | + // TYPENAME_FROM_MACRO var; |
| 56 | + // |
| 57 | + // but not if the entire declaration comes from |
| 58 | + // one: |
| 59 | + // |
| 60 | + // DEFINE_SOME_VARIABLE(); |
| 61 | + // |
| 62 | + // or if the definition comes from a macro like SWAP |
| 63 | + // that uses an internal temporary variable. |
| 64 | + // |
| 65 | + // Thus check that the variable name does |
| 66 | + // not come from a macro expansion. |
| 67 | + if (MatchedDecl->getEndLoc().isMacroID()) |
| 68 | + return; |
| 69 | + |
| 70 | + QualType TypePtr = MatchedDecl->getType(); |
| 71 | + const char *InitializationString = nullptr; |
| 72 | + bool AddMathInclude = false; |
| 73 | + |
| 74 | + if (TypePtr->isIntegerType()) |
| 75 | + InitializationString = " = 0"; |
| 76 | + else if (TypePtr->isFloatingType()) { |
| 77 | + InitializationString = " = NAN"; |
| 78 | + AddMathInclude = true; |
| 79 | + } else if (TypePtr->isAnyPointerType()) { |
| 80 | + if (getLangOpts().CPlusPlus11) |
| 81 | + InitializationString = " = nullptr"; |
| 82 | + else |
| 83 | + InitializationString = " = NULL"; |
| 84 | + } |
| 85 | + |
| 86 | + if (InitializationString) { |
| 87 | + auto Diagnostic = |
| 88 | + diag(MatchedDecl->getLocation(), "variable %0 is not initialized") |
| 89 | + << MatchedDecl |
| 90 | + << FixItHint::CreateInsertion( |
| 91 | + MatchedDecl->getLocation().getLocWithOffset( |
| 92 | + MatchedDecl->getName().size()), |
| 93 | + InitializationString); |
| 94 | + if (AddMathInclude) { |
| 95 | + auto IncludeHint = IncludeInserter->CreateIncludeInsertion( |
| 96 | + Source.getFileID(MatchedDecl->getBeginLoc()), MathHeader, false); |
| 97 | + if (IncludeHint) |
| 98 | + Diagnostic << *IncludeHint; |
| 99 | + } |
| 100 | + } |
| 101 | +} |
| 102 | + |
| 103 | +} // namespace cppcoreguidelines |
| 104 | +} // namespace tidy |
| 105 | +} // namespace clang |
0 commit comments