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-rw-r--r--clang/lib/StaticAnalyzer/Checkers/UndefinedAssignmentChecker.cpp88
1 files changed, 88 insertions, 0 deletions
diff --git a/clang/lib/StaticAnalyzer/Checkers/UndefinedAssignmentChecker.cpp b/clang/lib/StaticAnalyzer/Checkers/UndefinedAssignmentChecker.cpp
new file mode 100644
index 0000000..78f7fa6
--- /dev/null
+++ b/clang/lib/StaticAnalyzer/Checkers/UndefinedAssignmentChecker.cpp
@@ -0,0 +1,88 @@
+//===--- UndefinedAssignmentChecker.h ---------------------------*- C++ -*--==//
+//
+// The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This defines UndefinedAssignmentChecker, a builtin check in ExprEngine that
+// checks for assigning undefined values.
+//
+//===----------------------------------------------------------------------===//
+
+#include "ClangSACheckers.h"
+#include "clang/StaticAnalyzer/Core/Checker.h"
+#include "clang/StaticAnalyzer/Core/CheckerManager.h"
+#include "clang/StaticAnalyzer/Core/PathSensitive/CheckerContext.h"
+#include "clang/StaticAnalyzer/Core/BugReporter/BugType.h"
+
+using namespace clang;
+using namespace ento;
+
+namespace {
+class UndefinedAssignmentChecker
+ : public Checker<check::Bind> {
+ mutable OwningPtr<BugType> BT;
+
+public:
+ void checkBind(SVal location, SVal val, const Stmt *S,
+ CheckerContext &C) const;
+};
+}
+
+void UndefinedAssignmentChecker::checkBind(SVal location, SVal val,
+ const Stmt *StoreE,
+ CheckerContext &C) const {
+ if (!val.isUndef())
+ return;
+
+ ExplodedNode *N = C.generateSink();
+
+ if (!N)
+ return;
+
+ const char *str = "Assigned value is garbage or undefined";
+
+ if (!BT)
+ BT.reset(new BuiltinBug(str));
+
+ // Generate a report for this bug.
+ const Expr *ex = 0;
+
+ while (StoreE) {
+ if (const BinaryOperator *B = dyn_cast<BinaryOperator>(StoreE)) {
+ if (B->isCompoundAssignmentOp()) {
+ ProgramStateRef state = C.getState();
+ if (state->getSVal(B->getLHS(), C.getLocationContext()).isUndef()) {
+ str = "The left expression of the compound assignment is an "
+ "uninitialized value. The computed value will also be garbage";
+ ex = B->getLHS();
+ break;
+ }
+ }
+
+ ex = B->getRHS();
+ break;
+ }
+
+ if (const DeclStmt *DS = dyn_cast<DeclStmt>(StoreE)) {
+ const VarDecl *VD = dyn_cast<VarDecl>(DS->getSingleDecl());
+ ex = VD->getInit();
+ }
+
+ break;
+ }
+
+ BugReport *R = new BugReport(*BT, str, N);
+ if (ex) {
+ R->addRange(ex->getSourceRange());
+ R->addVisitor(bugreporter::getTrackNullOrUndefValueVisitor(N, ex, R));
+ }
+ C.EmitReport(R);
+}
+
+void ento::registerUndefinedAssignmentChecker(CheckerManager &mgr) {
+ mgr.registerChecker<UndefinedAssignmentChecker>();
+}