llvm-project/clang/lib/Analysis/ReturnUndefChecker.cpp

69 lines
1.9 KiB
C++

//== ReturnUndefChecker.cpp -------------------------------------*- C++ -*--==//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file defines ReturnUndefChecker, which is a path-sensitive
// check which looks for undefined or garbage values being returned to the
// caller.
//
//===----------------------------------------------------------------------===//
#include "GRExprEngineInternalChecks.h"
#include "clang/Analysis/PathSensitive/GRExprEngine.h"
#include "clang/Analysis/PathSensitive/BugReporter.h"
#include "clang/Analysis/PathSensitive/CheckerVisitor.h"
#include "llvm/ADT/SmallString.h"
using namespace clang;
namespace {
class VISIBILITY_HIDDEN ReturnUndefChecker :
public CheckerVisitor<ReturnUndefChecker> {
BuiltinBug *BT;
public:
ReturnUndefChecker() : BT(0) {}
static void *getTag();
void PreVisitReturnStmt(CheckerContext &C, const ReturnStmt *RS);
};
}
void clang::RegisterReturnUndefChecker(GRExprEngine &Eng) {
Eng.registerCheck(new ReturnUndefChecker());
}
void *ReturnUndefChecker::getTag() {
static int x = 0; return &x;
}
void ReturnUndefChecker::PreVisitReturnStmt(CheckerContext &C,
const ReturnStmt *RS) {
const Expr *RetE = RS->getRetValue();
if (!RetE)
return;
if (!C.getState()->getSVal(RetE).isUndef())
return;
ExplodedNode *N = C.GenerateSink();
if (!N)
return;
if (!BT)
BT = new BuiltinBug("Garbage return value",
"Undefined or garbage value returned to caller");
EnhancedBugReport *report =
new EnhancedBugReport(*BT, BT->getDescription(), N);
report->addVisitorCreator(bugreporter::registerTrackNullOrUndefValue, RetE);
C.EmitReport(report);
}