| 1 | //===--- UndefinedArraySubscriptChecker.h ----------------------*- C++ -*--===// |
|---|---|
| 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 | // This defines UndefinedArraySubscriptChecker, a builtin check in ExprEngine |
| 10 | // that performs checks for undefined array subscripts. |
| 11 | // |
| 12 | //===----------------------------------------------------------------------===// |
| 13 | |
| 14 | #include "clang/StaticAnalyzer/Checkers/BuiltinCheckerRegistration.h" |
| 15 | #include "clang/AST/DeclCXX.h" |
| 16 | #include "clang/StaticAnalyzer/Core/BugReporter/BugType.h" |
| 17 | #include "clang/StaticAnalyzer/Core/Checker.h" |
| 18 | #include "clang/StaticAnalyzer/Core/CheckerManager.h" |
| 19 | #include "clang/StaticAnalyzer/Core/PathSensitive/CheckerContext.h" |
| 20 | |
| 21 | using namespace clang; |
| 22 | using namespace ento; |
| 23 | |
| 24 | namespace { |
| 25 | class UndefinedArraySubscriptChecker |
| 26 | : public Checker< check::PreStmt<ArraySubscriptExpr> > { |
| 27 | const BugType BT{this, "Array subscript is undefined"}; |
| 28 | |
| 29 | public: |
| 30 | void checkPreStmt(const ArraySubscriptExpr *A, CheckerContext &C) const; |
| 31 | }; |
| 32 | } // end anonymous namespace |
| 33 | |
| 34 | void |
| 35 | UndefinedArraySubscriptChecker::checkPreStmt(const ArraySubscriptExpr *A, |
| 36 | CheckerContext &C) const { |
| 37 | const Expr *Index = A->getIdx(); |
| 38 | if (!C.getSVal(Index).isUndef()) |
| 39 | return; |
| 40 | |
| 41 | // Sema generates anonymous array variables for copying array struct fields. |
| 42 | // Don't warn if we're in an implicitly-generated constructor. |
| 43 | const Decl *D = C.getLocationContext()->getDecl(); |
| 44 | if (const CXXConstructorDecl *Ctor = dyn_cast<CXXConstructorDecl>(Val: D)) |
| 45 | if (Ctor->isDefaulted()) |
| 46 | return; |
| 47 | |
| 48 | ExplodedNode *N = C.generateErrorNode(); |
| 49 | if (!N) |
| 50 | return; |
| 51 | // Generate a report for this bug. |
| 52 | auto R = std::make_unique<PathSensitiveBugReport>(args: BT, args: BT.getDescription(), args&: N); |
| 53 | R->addRange(R: A->getIdx()->getSourceRange()); |
| 54 | bugreporter::trackExpressionValue(N, E: A->getIdx(), R&: *R); |
| 55 | C.emitReport(R: std::move(R)); |
| 56 | } |
| 57 | |
| 58 | void ento::registerUndefinedArraySubscriptChecker(CheckerManager &mgr) { |
| 59 | mgr.registerChecker<UndefinedArraySubscriptChecker>(); |
| 60 | } |
| 61 | |
| 62 | bool ento::shouldRegisterUndefinedArraySubscriptChecker(const CheckerManager &mgr) { |
| 63 | return true; |
| 64 | } |
| 65 |