From: Anna Zaks Date: Wed, 17 Apr 2013 22:29:47 +0000 (+0000) Subject: [analyzer] Allow TrackConstraintBRVisitor to work when the value it’s tracking is... X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=5b90ae7ba05a10a81f107ec1635deb1bd7292936;p=clang [analyzer] Allow TrackConstraintBRVisitor to work when the value it’s tracking is not live in the last node of the path We always register the visitor on a node in which the value we are tracking is live and constrained. However, the visitation can restart at a node, later on the path, in which the value is under constrained because it is no longer live. Previously, we just silently stopped tracking in that case. git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@179731 91177308-0d34-0410-b5e6-96231b3b80d8 --- diff --git a/include/clang/StaticAnalyzer/Core/BugReporter/BugReporterVisitor.h b/include/clang/StaticAnalyzer/Core/BugReporter/BugReporterVisitor.h index 2e5f207f4b..2e67180bea 100644 --- a/include/clang/StaticAnalyzer/Core/BugReporter/BugReporterVisitor.h +++ b/include/clang/StaticAnalyzer/Core/BugReporter/BugReporterVisitor.h @@ -134,10 +134,15 @@ class TrackConstraintBRVisitor bool IsSatisfied; bool IsZeroCheck; + /// We should start tracking from the last node along the path in which the + /// value is constrained. + bool IsTrackingTurnedOn; + public: TrackConstraintBRVisitor(DefinedSVal constraint, bool assumption) : Constraint(constraint), Assumption(assumption), IsSatisfied(false), - IsZeroCheck(!Assumption && Constraint.getAs()) {} + IsZeroCheck(!Assumption && Constraint.getAs()), + IsTrackingTurnedOn(false) {} void Profile(llvm::FoldingSetNodeID &ID) const; diff --git a/lib/StaticAnalyzer/Core/BugReporterVisitors.cpp b/lib/StaticAnalyzer/Core/BugReporterVisitors.cpp index 18994ca0d0..11a1727645 100644 --- a/lib/StaticAnalyzer/Core/BugReporterVisitors.cpp +++ b/lib/StaticAnalyzer/Core/BugReporterVisitors.cpp @@ -699,6 +699,14 @@ TrackConstraintBRVisitor::VisitNode(const ExplodedNode *N, if (IsSatisfied) return NULL; + // Start tracking after we see the first state in which the value is + // constrained. + if (!IsTrackingTurnedOn) + if (!isUnderconstrained(N)) + IsTrackingTurnedOn = true; + if (!IsTrackingTurnedOn) + return 0; + // Check if in the previous state it was feasible for this constraint // to *not* be true. if (isUnderconstrained(PrevN)) { @@ -708,8 +716,7 @@ TrackConstraintBRVisitor::VisitNode(const ExplodedNode *N, // As a sanity check, make sure that the negation of the constraint // was infeasible in the current state. If it is feasible, we somehow // missed the transition point. - if (isUnderconstrained(N)) - return NULL; + assert(!isUnderconstrained(N)); // We found the transition point for the constraint. We now need to // pretty-print the constraint. (work-in-progress) diff --git a/test/Analysis/diagnostics/deref-track-symbolic-region.c b/test/Analysis/diagnostics/deref-track-symbolic-region.c index 94774dd61d..03716de9ff 100644 --- a/test/Analysis/diagnostics/deref-track-symbolic-region.c +++ b/test/Analysis/diagnostics/deref-track-symbolic-region.c @@ -24,6 +24,21 @@ void test(struct S syz, int *pp) { // expected-note@-1{{Dereference of null pointer (loaded from field 'x')}} } +void testTrackConstraintBRVisitorIsTrackingTurnedOn(struct S syz, int *pp) { + int m = 0; + syz.x = foo(); // expected-note{{Value assigned to 'syz.x'}} + + struct S *ps = &syz; + if (ps->x) + //expected-note@-1{{Taking false branch}} + //expected-note@-2{{Assuming pointer value is null}} + + m++; + int *p = syz.x; //expected-note {{'p' initialized to a null pointer value}} + m = *p; // expected-warning {{Dereference of null pointer (loaded from variable 'p')}} + // expected-note@-1 {{Dereference of null pointer (loaded from variable 'p')}} +} + // CHECK: diagnostics // CHECK-NEXT: // CHECK-NEXT: @@ -300,6 +315,341 @@ void test(struct S syz, int *pp) { // CHECK-NEXT: file0 // CHECK-NEXT: // CHECK-NEXT: +// CHECK-NEXT: +// CHECK-NEXT: path +// CHECK-NEXT: +// CHECK-NEXT: +// CHECK-NEXT: kindcontrol +// CHECK-NEXT: edges +// CHECK-NEXT: +// CHECK-NEXT: +// CHECK-NEXT: start +// CHECK-NEXT: +// CHECK-NEXT: +// CHECK-NEXT: line28 +// CHECK-NEXT: col3 +// CHECK-NEXT: file0 +// CHECK-NEXT: +// CHECK-NEXT: +// CHECK-NEXT: line28 +// CHECK-NEXT: col5 +// CHECK-NEXT: file0 +// CHECK-NEXT: +// CHECK-NEXT: +// CHECK-NEXT: end +// CHECK-NEXT: +// CHECK-NEXT: +// CHECK-NEXT: line29 +// CHECK-NEXT: col3 +// CHECK-NEXT: file0 +// CHECK-NEXT: +// CHECK-NEXT: +// CHECK-NEXT: line29 +// CHECK-NEXT: col5 +// CHECK-NEXT: file0 +// CHECK-NEXT: +// CHECK-NEXT: +// CHECK-NEXT: +// CHECK-NEXT: +// CHECK-NEXT: +// CHECK-NEXT: +// CHECK-NEXT: kindevent +// CHECK-NEXT: location +// CHECK-NEXT: +// CHECK-NEXT: line29 +// CHECK-NEXT: col3 +// CHECK-NEXT: file0 +// CHECK-NEXT: +// CHECK-NEXT: ranges +// CHECK-NEXT: +// CHECK-NEXT: +// CHECK-NEXT: +// CHECK-NEXT: line29 +// CHECK-NEXT: col3 +// CHECK-NEXT: file0 +// CHECK-NEXT: +// CHECK-NEXT: +// CHECK-NEXT: line29 +// CHECK-NEXT: col15 +// CHECK-NEXT: file0 +// CHECK-NEXT: +// CHECK-NEXT: +// CHECK-NEXT: +// CHECK-NEXT: depth0 +// CHECK-NEXT: extended_message +// CHECK-NEXT: Value assigned to 'syz.x' +// CHECK-NEXT: message +// CHECK-NEXT: Value assigned to 'syz.x' +// CHECK-NEXT: +// CHECK-NEXT: +// CHECK-NEXT: kindcontrol +// CHECK-NEXT: edges +// CHECK-NEXT: +// CHECK-NEXT: +// CHECK-NEXT: start +// CHECK-NEXT: +// CHECK-NEXT: +// CHECK-NEXT: line29 +// CHECK-NEXT: col3 +// CHECK-NEXT: file0 +// CHECK-NEXT: +// CHECK-NEXT: +// CHECK-NEXT: line29 +// CHECK-NEXT: col5 +// CHECK-NEXT: file0 +// CHECK-NEXT: +// CHECK-NEXT: +// CHECK-NEXT: end +// CHECK-NEXT: +// CHECK-NEXT: +// CHECK-NEXT: line32 +// CHECK-NEXT: col3 +// CHECK-NEXT: file0 +// CHECK-NEXT: +// CHECK-NEXT: +// CHECK-NEXT: line32 +// CHECK-NEXT: col4 +// CHECK-NEXT: file0 +// CHECK-NEXT: +// CHECK-NEXT: +// CHECK-NEXT: +// CHECK-NEXT: +// CHECK-NEXT: +// CHECK-NEXT: +// CHECK-NEXT: kindcontrol +// CHECK-NEXT: edges +// CHECK-NEXT: +// CHECK-NEXT: +// CHECK-NEXT: start +// CHECK-NEXT: +// CHECK-NEXT: +// CHECK-NEXT: line32 +// CHECK-NEXT: col3 +// CHECK-NEXT: file0 +// CHECK-NEXT: +// CHECK-NEXT: +// CHECK-NEXT: line32 +// CHECK-NEXT: col4 +// CHECK-NEXT: file0 +// CHECK-NEXT: +// CHECK-NEXT: +// CHECK-NEXT: end +// CHECK-NEXT: +// CHECK-NEXT: +// CHECK-NEXT: line32 +// CHECK-NEXT: col7 +// CHECK-NEXT: file0 +// CHECK-NEXT: +// CHECK-NEXT: +// CHECK-NEXT: line32 +// CHECK-NEXT: col8 +// CHECK-NEXT: file0 +// CHECK-NEXT: +// CHECK-NEXT: +// CHECK-NEXT: +// CHECK-NEXT: +// CHECK-NEXT: +// CHECK-NEXT: +// CHECK-NEXT: kindevent +// CHECK-NEXT: location +// CHECK-NEXT: +// CHECK-NEXT: line32 +// CHECK-NEXT: col7 +// CHECK-NEXT: file0 +// CHECK-NEXT: +// CHECK-NEXT: ranges +// CHECK-NEXT: +// CHECK-NEXT: +// CHECK-NEXT: +// CHECK-NEXT: line32 +// CHECK-NEXT: col7 +// CHECK-NEXT: file0 +// CHECK-NEXT: +// CHECK-NEXT: +// CHECK-NEXT: line32 +// CHECK-NEXT: col11 +// CHECK-NEXT: file0 +// CHECK-NEXT: +// CHECK-NEXT: +// CHECK-NEXT: +// CHECK-NEXT: depth0 +// CHECK-NEXT: extended_message +// CHECK-NEXT: Assuming pointer value is null +// CHECK-NEXT: message +// CHECK-NEXT: Assuming pointer value is null +// CHECK-NEXT: +// CHECK-NEXT: +// CHECK-NEXT: kindcontrol +// CHECK-NEXT: edges +// CHECK-NEXT: +// CHECK-NEXT: +// CHECK-NEXT: start +// CHECK-NEXT: +// CHECK-NEXT: +// CHECK-NEXT: line32 +// CHECK-NEXT: col7 +// CHECK-NEXT: file0 +// CHECK-NEXT: +// CHECK-NEXT: +// CHECK-NEXT: line32 +// CHECK-NEXT: col8 +// CHECK-NEXT: file0 +// CHECK-NEXT: +// CHECK-NEXT: +// CHECK-NEXT: end +// CHECK-NEXT: +// CHECK-NEXT: +// CHECK-NEXT: line37 +// CHECK-NEXT: col3 +// CHECK-NEXT: file0 +// CHECK-NEXT: +// CHECK-NEXT: +// CHECK-NEXT: line37 +// CHECK-NEXT: col5 +// CHECK-NEXT: file0 +// CHECK-NEXT: +// CHECK-NEXT: +// CHECK-NEXT: +// CHECK-NEXT: +// CHECK-NEXT: +// CHECK-NEXT: +// CHECK-NEXT: kindevent +// CHECK-NEXT: location +// CHECK-NEXT: +// CHECK-NEXT: line37 +// CHECK-NEXT: col3 +// CHECK-NEXT: file0 +// CHECK-NEXT: +// CHECK-NEXT: ranges +// CHECK-NEXT: +// CHECK-NEXT: +// CHECK-NEXT: +// CHECK-NEXT: line37 +// CHECK-NEXT: col3 +// CHECK-NEXT: file0 +// CHECK-NEXT: +// CHECK-NEXT: +// CHECK-NEXT: line37 +// CHECK-NEXT: col8 +// CHECK-NEXT: file0 +// CHECK-NEXT: +// CHECK-NEXT: +// CHECK-NEXT: +// CHECK-NEXT: depth0 +// CHECK-NEXT: extended_message +// CHECK-NEXT: 'p' initialized to a null pointer value +// CHECK-NEXT: message +// CHECK-NEXT: 'p' initialized to a null pointer value +// CHECK-NEXT: +// CHECK-NEXT: +// CHECK-NEXT: kindcontrol +// CHECK-NEXT: edges +// CHECK-NEXT: +// CHECK-NEXT: +// CHECK-NEXT: start +// CHECK-NEXT: +// CHECK-NEXT: +// CHECK-NEXT: line37 +// CHECK-NEXT: col3 +// CHECK-NEXT: file0 +// CHECK-NEXT: +// CHECK-NEXT: +// CHECK-NEXT: line37 +// CHECK-NEXT: col5 +// CHECK-NEXT: file0 +// CHECK-NEXT: +// CHECK-NEXT: +// CHECK-NEXT: end +// CHECK-NEXT: +// CHECK-NEXT: +// CHECK-NEXT: line38 +// CHECK-NEXT: col3 +// CHECK-NEXT: file0 +// CHECK-NEXT: +// CHECK-NEXT: +// CHECK-NEXT: line38 +// CHECK-NEXT: col3 +// CHECK-NEXT: file0 +// CHECK-NEXT: +// CHECK-NEXT: +// CHECK-NEXT: +// CHECK-NEXT: +// CHECK-NEXT: +// CHECK-NEXT: +// CHECK-NEXT: kindcontrol +// CHECK-NEXT: edges +// CHECK-NEXT: +// CHECK-NEXT: +// CHECK-NEXT: start +// CHECK-NEXT: +// CHECK-NEXT: +// CHECK-NEXT: line38 +// CHECK-NEXT: col3 +// CHECK-NEXT: file0 +// CHECK-NEXT: +// CHECK-NEXT: +// CHECK-NEXT: line38 +// CHECK-NEXT: col3 +// CHECK-NEXT: file0 +// CHECK-NEXT: +// CHECK-NEXT: +// CHECK-NEXT: end +// CHECK-NEXT: +// CHECK-NEXT: +// CHECK-NEXT: line38 +// CHECK-NEXT: col7 +// CHECK-NEXT: file0 +// CHECK-NEXT: +// CHECK-NEXT: +// CHECK-NEXT: line38 +// CHECK-NEXT: col7 +// CHECK-NEXT: file0 +// CHECK-NEXT: +// CHECK-NEXT: +// CHECK-NEXT: +// CHECK-NEXT: +// CHECK-NEXT: +// CHECK-NEXT: +// CHECK-NEXT: kindevent +// CHECK-NEXT: location +// CHECK-NEXT: +// CHECK-NEXT: line38 +// CHECK-NEXT: col7 +// CHECK-NEXT: file0 +// CHECK-NEXT: +// CHECK-NEXT: ranges +// CHECK-NEXT: +// CHECK-NEXT: +// CHECK-NEXT: +// CHECK-NEXT: line38 +// CHECK-NEXT: col8 +// CHECK-NEXT: file0 +// CHECK-NEXT: +// CHECK-NEXT: +// CHECK-NEXT: line38 +// CHECK-NEXT: col8 +// CHECK-NEXT: file0 +// CHECK-NEXT: +// CHECK-NEXT: +// CHECK-NEXT: +// CHECK-NEXT: depth0 +// CHECK-NEXT: extended_message +// CHECK-NEXT: Dereference of null pointer (loaded from variable 'p') +// CHECK-NEXT: message +// CHECK-NEXT: Dereference of null pointer (loaded from variable 'p') +// CHECK-NEXT: +// CHECK-NEXT: +// CHECK-NEXT: descriptionDereference of null pointer (loaded from variable 'p') +// CHECK-NEXT: categoryLogic error +// CHECK-NEXT: typeDereference of null pointer +// CHECK-NEXT: issue_context_kindfunction +// CHECK-NEXT: issue_contexttestTrackConstraintBRVisitorIsTrackingTurnedOn +// CHECK-NEXT: issue_hash11 +// CHECK-NEXT: location +// CHECK-NEXT: +// CHECK-NEXT: line38 +// CHECK-NEXT: col7 +// CHECK-NEXT: file0 +// CHECK-NEXT: +// CHECK-NEXT: // CHECK-NEXT: -// CHECK-NEXT: -// CHECK-NEXT: