llvm-project/clang/lib/StaticAnalyzer/Checkers/UndefinedArraySubscriptChecker.cpp
Donát Nagy 8a5cfdf785 [analyzer][NFC] Remove useless class BuiltinBug
...because it provides no useful functionality compared to its base
class `BugType`.

A long time ago there were substantial differences between `BugType` and
`BuiltinBug`, but they were eliminated by commit 1bd58233 in 2009 (!).
Since then the only functionality provided by `BuiltinBug` was that it
specified `categories::LogicError` as the bug category and it stored an
extra data member `desc`.

This commit sets `categories::LogicError` as the default value of the
third argument (bug category) in the constructors of BugType and
replaces use of the `desc` field with simpler logic.

Note that `BugType` has a data member `Description` and a non-virtual
method `BugType::getDescription()` which queries it; these are distinct
from the member `desc` of `BuiltinBug` and the identically named method
`BuiltinBug::getDescription()` which queries it. This confusing name
collision was a major motivation for the elimination of `BuiltinBug`.

As this commit touches many files, I avoided functional changes and left
behind FIXME notes to mark minor issues that should be fixed later.

Differential Revision: https://reviews.llvm.org/D158855
2023-08-28 15:20:14 +02:00

68 lines
2.4 KiB
C++

//===--- UndefinedArraySubscriptChecker.h ----------------------*- C++ -*--===//
//
// 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
//
//===----------------------------------------------------------------------===//
//
// This defines UndefinedArraySubscriptChecker, a builtin check in ExprEngine
// that performs checks for undefined array subscripts.
//
//===----------------------------------------------------------------------===//
#include "clang/StaticAnalyzer/Checkers/BuiltinCheckerRegistration.h"
#include "clang/AST/DeclCXX.h"
#include "clang/StaticAnalyzer/Core/BugReporter/BugType.h"
#include "clang/StaticAnalyzer/Core/Checker.h"
#include "clang/StaticAnalyzer/Core/CheckerManager.h"
#include "clang/StaticAnalyzer/Core/PathSensitive/CheckerContext.h"
using namespace clang;
using namespace ento;
namespace {
class UndefinedArraySubscriptChecker
: public Checker< check::PreStmt<ArraySubscriptExpr> > {
mutable std::unique_ptr<BugType> BT;
public:
void checkPreStmt(const ArraySubscriptExpr *A, CheckerContext &C) const;
};
} // end anonymous namespace
void
UndefinedArraySubscriptChecker::checkPreStmt(const ArraySubscriptExpr *A,
CheckerContext &C) const {
const Expr *Index = A->getIdx();
if (!C.getSVal(Index).isUndef())
return;
// Sema generates anonymous array variables for copying array struct fields.
// Don't warn if we're in an implicitly-generated constructor.
const Decl *D = C.getLocationContext()->getDecl();
if (const CXXConstructorDecl *Ctor = dyn_cast<CXXConstructorDecl>(D))
if (Ctor->isDefaulted())
return;
ExplodedNode *N = C.generateErrorNode();
if (!N)
return;
if (!BT)
BT.reset(new BugType(this, "Array subscript is undefined"));
// Generate a report for this bug.
auto R = std::make_unique<PathSensitiveBugReport>(*BT, BT->getDescription(), N);
R->addRange(A->getIdx()->getSourceRange());
bugreporter::trackExpressionValue(N, A->getIdx(), *R);
C.emitReport(std::move(R));
}
void ento::registerUndefinedArraySubscriptChecker(CheckerManager &mgr) {
mgr.registerChecker<UndefinedArraySubscriptChecker>();
}
bool ento::shouldRegisterUndefinedArraySubscriptChecker(const CheckerManager &mgr) {
return true;
}