clang-tools-extra/clang-tidy/bugprone/UncheckedOptionalAccessCheck.cpp

   1 //===--- UncheckedOptionalAccessCheck.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 "UncheckedOptionalAccessCheck.h"
  10 #include "clang/AST/ASTContext.h"
  11 #include "clang/ASTMatchers/ASTMatchFinder.h"
  12 #include "clang/ASTMatchers/ASTMatchers.h"
  13 #include "clang/Analysis/FlowSensitive/DataflowAnalysis.h"
  14 #include "clang/Analysis/FlowSensitive/Models/UncheckedOptionalAccessModel.h"
  15 #include "clang/Basic/SourceLocation.h"
  16 #include "llvm/ADT/SmallVector.h"
  17 #include "llvm/Support/Error.h"
  18
  19 namespace clang::tidy::bugprone {
  20 using ast_matchers::MatchFinder;
  21 using dataflow::UncheckedOptionalAccessDiagnoser;
  22 using dataflow::UncheckedOptionalAccessModel;
  23
  24 static constexpr llvm::StringLiteral FuncID("fun");
  25
  26 void UncheckedOptionalAccessCheck::registerMatchers(MatchFinder *Finder) {
  27   using namespace ast_matchers;
  28
  29   auto HasOptionalCallDescendant = hasDescendant(callExpr(callee(cxxMethodDecl(
  30       ofClass(UncheckedOptionalAccessModel::optionalClassDecl())))));
  31   Finder->addMatcher(
  32       decl(anyOf(functionDecl(unless(isExpansionInSystemHeader()),
  33                               // FIXME: Remove the filter below when lambdas are
  34                               // well supported by the check.
  35                               unless(hasDeclContext(cxxRecordDecl(isLambda()))),
  36                               hasBody(HasOptionalCallDescendant)),
  37                  cxxConstructorDecl(hasAnyConstructorInitializer(
  38                      withInitializer(HasOptionalCallDescendant)))))
  39           .bind(FuncID),
  40       this);
  41 }
  42
  43 void UncheckedOptionalAccessCheck::check(
  44     const MatchFinder::MatchResult &Result) {
  45   if (Result.SourceManager->getDiagnostics().hasUncompilableErrorOccurred())
  46     return;
  47
  48   const auto *FuncDecl = Result.Nodes.getNodeAs<FunctionDecl>(FuncID);
  49   if (FuncDecl->isTemplated())
  50     return;
  51
  52   UncheckedOptionalAccessDiagnoser Diagnoser(ModelOptions);
  53   // FIXME: Allow user to set the (defaulted) SAT iterations max for
  54   // `diagnoseFunction` with config options.
  55   if (llvm::Expected<llvm::SmallVector<SourceLocation>> Locs =
  56           dataflow::diagnoseFunction<UncheckedOptionalAccessModel,
  57                                      SourceLocation>(*FuncDecl, *Result.Context,
  58                                                      Diagnoser))
  59     for (const SourceLocation &Loc : *Locs)
  60       diag(Loc, "unchecked access to optional value");
  61   else
  62     llvm::consumeError(Locs.takeError());
  63 }
  64
  65 } // namespace clang::tidy::bugprone