97 lines
		
	
	
		
			2.8 KiB
		
	
	
	
		
			C++
		
	
	
	
	
	
			
		
		
	
	
			97 lines
		
	
	
		
			2.8 KiB
		
	
	
	
		
			C++
		
	
	
	
	
	
| //===--- UndefinedAssignmentChecker.h ---------------------------*- C++ -*--==//
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| //
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| //                     The LLVM Compiler Infrastructure
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| //
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| // This file is distributed under the University of Illinois Open Source
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| // License. See LICENSE.TXT for details.
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| //
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| //===----------------------------------------------------------------------===//
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| //
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| // This defines UndefinedAssignmentChecker, a builtin check in ExprEngine that
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| // checks for assigning undefined values.
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| //
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| //===----------------------------------------------------------------------===//
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| 
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| #include "ClangSACheckers.h"
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| #include "clang/StaticAnalyzer/Core/BugReporter/BugType.h"
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| #include "clang/StaticAnalyzer/Core/Checker.h"
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| #include "clang/StaticAnalyzer/Core/CheckerManager.h"
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| #include "clang/StaticAnalyzer/Core/PathSensitive/CheckerContext.h"
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| 
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| using namespace clang;
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| using namespace ento;
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| 
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| namespace {
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| class UndefinedAssignmentChecker
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|   : public Checker<check::Bind> {
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|   mutable OwningPtr<BugType> BT;
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| 
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| public:
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|   void checkBind(SVal location, SVal val, const Stmt *S,
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|                  CheckerContext &C) const;
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| };
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| }
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| 
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| void UndefinedAssignmentChecker::checkBind(SVal location, SVal val,
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|                                            const Stmt *StoreE,
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|                                            CheckerContext &C) const {
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|   if (!val.isUndef())
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|     return;
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| 
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|   // Do not report assignments of uninitialized values inside swap functions.
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|   // This should allow to swap partially uninitialized structs
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|   // (radar://14129997)
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|   if (const FunctionDecl *EnclosingFunctionDecl =
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|       dyn_cast<FunctionDecl>(C.getStackFrame()->getDecl()))
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|     if (C.getCalleeName(EnclosingFunctionDecl) == "swap")
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|       return;
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| 
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|   ExplodedNode *N = C.generateSink();
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| 
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|   if (!N)
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|     return;
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| 
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|   const char *str = "Assigned value is garbage or undefined";
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| 
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|   if (!BT)
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|     BT.reset(new BuiltinBug(str));
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| 
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|   // Generate a report for this bug.
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|   const Expr *ex = 0;
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| 
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|   while (StoreE) {
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|     if (const BinaryOperator *B = dyn_cast<BinaryOperator>(StoreE)) {
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|       if (B->isCompoundAssignmentOp()) {
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|         ProgramStateRef state = C.getState();
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|         if (state->getSVal(B->getLHS(), C.getLocationContext()).isUndef()) {
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|           str = "The left expression of the compound assignment is an "
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|                 "uninitialized value. The computed value will also be garbage";
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|           ex = B->getLHS();
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|           break;
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|         }
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|       }
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| 
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|       ex = B->getRHS();
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|       break;
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|     }
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| 
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|     if (const DeclStmt *DS = dyn_cast<DeclStmt>(StoreE)) {
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|       const VarDecl *VD = dyn_cast<VarDecl>(DS->getSingleDecl());
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|       ex = VD->getInit();
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|     }
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| 
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|     break;
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|   }
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| 
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|   BugReport *R = new BugReport(*BT, str, N);
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|   if (ex) {
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|     R->addRange(ex->getSourceRange());
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|     bugreporter::trackNullOrUndefValue(N, ex, *R);
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|   }
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|   C.emitReport(R);
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| }
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| 
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| void ento::registerUndefinedAssignmentChecker(CheckerManager &mgr) {
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|   mgr.registerChecker<UndefinedAssignmentChecker>();
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| }
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