llvm-project

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//===--- UncheckedOptionalAccessCheck.cpp - clang-tidy --------------------===//
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//
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// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
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// See https://llvm.org/LICENSE.txt for license information.
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// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
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//
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//===----------------------------------------------------------------------===//
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#include "UncheckedOptionalAccessCheck.h"
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#include "clang/AST/ASTContext.h"
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#include "clang/ASTMatchers/ASTMatchFinder.h"
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#include "clang/ASTMatchers/ASTMatchers.h"
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#include "clang/Analysis/FlowSensitive/DataflowAnalysis.h"
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#include "clang/Analysis/FlowSensitive/Models/UncheckedOptionalAccessModel.h"
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#include "clang/Basic/SourceLocation.h"
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#include "llvm/ADT/SmallVector.h"
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#include "llvm/Support/Error.h"
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namespace clang::tidy::bugprone {
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using ast_matchers::MatchFinder;
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using dataflow::UncheckedOptionalAccessDiagnoser;
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using dataflow::UncheckedOptionalAccessModel;
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static constexpr llvm::StringLiteral FuncID("fun");
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void UncheckedOptionalAccessCheck::registerMatchers(MatchFinder *Finder) {
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  using namespace ast_matchers;
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  auto HasOptionalCallDescendant = hasDescendant(callExpr(callee(cxxMethodDecl(
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      ofClass(UncheckedOptionalAccessModel::optionalClassDecl())))));
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  Finder->addMatcher(
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      decl(anyOf(functionDecl(unless(isExpansionInSystemHeader()),
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                              // FIXME: Remove the filter below when lambdas are
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                              // well supported by the check.
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                              unless(hasDeclContext(cxxRecordDecl(isLambda()))),
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                              hasBody(HasOptionalCallDescendant)),
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                 cxxConstructorDecl(hasAnyConstructorInitializer(
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                     withInitializer(HasOptionalCallDescendant)))))
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          .bind(FuncID),
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      this);
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}
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void UncheckedOptionalAccessCheck::check(
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    const MatchFinder::MatchResult &Result) {
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  if (Result.SourceManager->getDiagnostics().hasUncompilableErrorOccurred())
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    return;
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  const auto *FuncDecl = Result.Nodes.getNodeAs<FunctionDecl>(FuncID);
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  if (FuncDecl->isTemplated())
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    return;
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  UncheckedOptionalAccessDiagnoser Diagnoser(ModelOptions);
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  // FIXME: Allow user to set the (defaulted) SAT iterations max for
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  // `diagnoseFunction` with config options.
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  if (llvm::Expected<llvm::SmallVector<SourceLocation>> Locs =
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          dataflow::diagnoseFunction<UncheckedOptionalAccessModel,
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                                     SourceLocation>(*FuncDecl, *Result.Context,
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                                                     Diagnoser))
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    for (const SourceLocation &Loc : *Locs)
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      diag(Loc, "unchecked access to optional value");
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  else
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    llvm::consumeError(Locs.takeError());
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}
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} // namespace clang::tidy::bugprone
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