clang: lib/StaticAnalyzer/Checkers/ReturnUndefChecker.cpp Source File (original) (raw)
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22using namespace clang;
23using namespace ento;
24
25namespace {
26class ReturnUndefChecker : public Checker< check::PreStmt > {
27 const BugType BT_Undef{this, "Garbage return value"};
28 const BugType BT_NullReference{this, "Returning null reference"};
29
30 void emitUndef(CheckerContext &C, const Expr *RetE) const;
31 void checkReference(CheckerContext &C, const Expr *RetE,
32 DefinedOrUnknownSVal RetVal) const;
33public:
34 void checkPreStmt(const ReturnStmt *RS, CheckerContext &C) const;
35};
36}
37
38void ReturnUndefChecker::checkPreStmt(const ReturnStmt *RS,
41 if (!RetE)
42 return;
43 SVal RetVal = C.getSVal(RetE);
44
45 const StackFrameContext *SFC = C.getStackFrame();
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58 return;
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65 return;
66
67 emitUndef(C, RetE);
68 return;
69 }
70
72 return;
73
75 checkReference(C, RetE, RetVal.castAs());
76 return;
77 }
78}
79
81 const Expr *RetE, const Expr *TrackingE = nullptr) {
83 if (!N)
84 return;
85
86 auto Report = std::make_unique(BT, Msg, N);
87
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91 C.emitReport(std::move(Report));
92}
93
94void ReturnUndefChecker::emitUndef(CheckerContext &C, const Expr *RetE) const {
95 emitBug(C, BT_Undef, "Undefined or garbage value returned to caller", RetE);
96}
97
98void ReturnUndefChecker::checkReference(CheckerContext &C, const Expr *RetE,
99 DefinedOrUnknownSVal RetVal) const {
101 std::tie(StNonNull, StNull) = C.getState()->assume(RetVal);
102
103 if (StNonNull) {
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105 C.addTransition(StNonNull);
106 return;
107 }
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109
112}
113
114void ento::registerReturnUndefChecker(CheckerManager &mgr) {
116}
117
118bool ento::shouldRegisterReturnUndefChecker(const CheckerManager &mgr) {
119 return true;
120}
static void emitBug(CheckerContext &C, const BugType &BT, StringRef Msg, const Expr *RetE, const Expr *TrackingE=nullptr)
Definition ReturnUndefChecker.cpp:80
This represents one expression.
const Decl * getDecl() const
bool isNull() const
Return true if this QualType doesn't point to a type yet.
ReturnStmt - This represents a return, optionally of an expression: return; return 4;.
SourceRange getSourceRange() const LLVM_READONLY
SourceLocation tokens are not useful in isolation - they are low level value objects created/interpre...
bool isReferenceType() const
StringRef getDescription() const
static QualType getDeclaredResultType(const Decl *D)
Returns the result type of a function or method declaration.
CHECKER * registerChecker(AT &&...Args)
Register a single-part checker (derived from Checker): construct its singleton instance,...
Simple checker classes that implement one frontend (i.e.
T castAs() const
Convert to the specified SVal type, asserting that this SVal is of the desired type.
const Expr * getDerefExpr(const Stmt *S)
Given that expression S represents a pointer that would be dereferenced, try to find a sub-expression...
bool trackExpressionValue(const ExplodedNode *N, const Expr *E, PathSensitiveBugReport &R, TrackingOptions Opts={})
Attempts to add visitors to track expression value back to its point of origin.
IntrusiveRefCntPtr< const ProgramState > ProgramStateRef
The JSON file list parser is used to communicate input to InstallAPI.
bool isa(CodeGen::Address addr)