[analyzer] If we dereference a NULL that came from a function, show the return.

More generally, any time we try to track where a null value came from, we
should show if it came from a function. This usually isn't necessary if
the value is symbolic, but if the value is just a constant we previously
just ignored its origin entirely. Now, we'll step into the function and
recursively add a visitor to the returned expression.

<rdar://problem/12114609>

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@162563 91177308-0d34-0410-b5e6-96231b3b80d8

2 files changed, 868 insertions, 0 deletions

diff --git a/lib/StaticAnalyzer/Core/BugReporterVisitors.cpp b/lib/StaticAnalyzer/Core/BugReporterVisitors.cpp
index e7295878fa..1dbd8f0379 100644
--- a/lib/StaticAnalyzer/Core/BugReporterVisitors.cpp
+++ b/lib/StaticAnalyzer/Core/BugReporterVisitors.cpp
@@ -296,6 +296,49 @@ TrackConstraintBRVisitor::VisitNode(const ExplodedNode *N,
   return NULL;
 }
 
+namespace {
+class ReturnNullVisitor : public BugReporterVisitorImpl<ReturnNullVisitor> {
+  const ExplodedNode *ReturnNode;
+public:
+  ReturnNullVisitor(const ExplodedNode *N) : ReturnNode(N) {}
+
+  virtual void Profile(llvm::FoldingSetNodeID &ID) const {
+    static int Tag = 0;
+    ID.AddPointer(&Tag);
+    ID.Add(*ReturnNode);
+  }
+
+  PathDiagnosticPiece *VisitNode(const ExplodedNode *N,
+                                 const ExplodedNode *PrevN,
+                                 BugReporterContext &BRC,
+                                 BugReport &BR) {
+    if (ReturnNode != BRC.getNodeResolver().getOriginalNode(N))
+      return 0;
+
+    StmtPoint SP = cast<StmtPoint>(ReturnNode->getLocation());
+    const ReturnStmt *Ret = cast<ReturnStmt>(SP.getStmt());
+    PathDiagnosticLocation L(Ret, BRC.getSourceManager(),
+                             N->getLocationContext());
+
+    SmallString<64> Msg;
+    llvm::raw_svector_ostream Out(Msg);
+
+    if (Loc::isLocType(Ret->getRetValue()->getType()))
+      Out << "Returning null pointer";
+    else
+      Out << "Returning zero";
+
+    // FIXME: We should have a more generalized printing mechanism.
+    const Expr *RetE = Ret->getRetValue()->IgnoreParenCasts();
+    if (const DeclRefExpr *DR = dyn_cast<DeclRefExpr>(RetE))
+      if (const DeclaratorDecl *DD = dyn_cast<DeclaratorDecl>(DR->getDecl()))
+        Out << " (loaded from '" << *DD << "')";
+
+    return new PathDiagnosticEventPiece(L, Out.str());
+  }
+};
+} // end anonymous namespace
+
 void bugreporter::addTrackNullOrUndefValueVisitor(const ExplodedNode *N,
                                                   const Stmt *S,
                                                   BugReport *report) {
@@ -311,6 +354,9 @@ void bugreporter::addTrackNullOrUndefValueVisitor(const ExplodedNode *N,
     if (const PostStmt *ps = dyn_cast<PostStmt>(&pp)) {
       if (ps->getStmt() == S)
         break;
+    } else if (const CallExitEnd *CEE = dyn_cast<CallExitEnd>(&pp)) {
+      if (CEE->getCalleeContext()->getCallSite() == S)
+        break;
     }
     N = N->getFirstPred();
   }
@@ -364,6 +410,28 @@ void bugreporter::addTrackNullOrUndefValueVisitor(const ExplodedNode *N,
       report->addVisitor(new TrackConstraintBRVisitor(loc::MemRegionVal(R),
                                                       false));
     }
+  } else {
+    // Walk backwards to just before the post-statement checks.
+    ProgramPoint PP = N->getLocation();
+    while (N && isa<PostStmt>(PP = N->getLocation()))
+      N = N->getFirstPred();
+
+    if (N && isa<CallExitEnd>(PP)) {
+      // Find a ReturnStmt, if there is one.
+      do {
+        N = N->getFirstPred();
+        PP = N->getLocation();
+      } while (!isa<StmtPoint>(PP) && !isa<CallEnter>(PP));
+
+      if (const StmtPoint *SP = dyn_cast<StmtPoint>(&PP)) {
+        if (const ReturnStmt *Ret = SP->getStmtAs<ReturnStmt>()) {
+          if (const Expr *RetE = Ret->getRetValue()) {
+            report->addVisitor(new ReturnNullVisitor(N));
+            addTrackNullOrUndefValueVisitor(N, RetE, report);
+          }
+        }
+      }
+    }
   }
 }
 
diff --git a/test/Analysis/inlining/path-notes.c b/test/Analysis/inlining/path-notes.c
index bd239152eb..66a2f270df 100644
--- a/test/Analysis/inlining/path-notes.c
+++ b/test/Analysis/inlining/path-notes.c
@@ -57,6 +57,38 @@ void testStoreCheck(int *a) {
 }
 
 
+int *getZero() {
+  int *p = 0;
+  // expected-note@-1 {{Variable 'p' initialized to a null pointer value}}
+  // ^ This note checks that we add a second visitor for the return value.
+  return p;
+  // expected-note@-1 {{Returning null pointer (loaded from 'p')}}
+}
+
+void testReturnZero() {
+  *getZero() = 1; // expected-warning{{Dereference of null pointer}}
+  // expected-note@-1 {{Calling 'getZero'}}
+  // expected-note@-2 {{Returning from 'getZero'}}
+  // expected-note@-3 {{Dereference of null pointer}}
+}
+
+void testInitZero() {
+  // FIXME: <rdar://problem/12114689> Diagnostics: Need to step into the function whose result is assigned to an interesting region
+  int *a = getZero();
+  // expected-note@-1 {{Variable 'a' initialized to a null pointer value}}
+  *a = 1; // expected-warning{{Dereference of null pointer}}
+  // expected-note@-1 {{Dereference of null pointer (loaded from variable 'a')}}
+}
+
+void testStoreZero(int *a) {
+  // FIXME: <rdar://problem/12114689> Diagnostics: Need to step into the function whose result is assigned to an interesting region
+  a = getZero();
+  // expected-note@-1 {{Null pointer value stored to 'a'}}
+  *a = 1; // expected-warning{{Dereference of null pointer}}
+  // expected-note@-1 {{Dereference of null pointer (loaded from variable 'a')}}
+}
+
+
 // CHECK: <?xml version="1.0" encoding="UTF-8"?>
 // CHECK: <!DOCTYPE plist PUBLIC "-//Apple Computer//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
 // CHECK: <plist version="1.0">
@@ -1286,6 +1318,774 @@ void testStoreCheck(int *a) {
 // CHECK:    <key>file</key><integer>0</integer>
 // CHECK:   </dict>
 // CHECK:   </dict>
+// CHECK:   <dict>
+// CHECK:    <key>path</key>
+// CHECK:    <array>
+// CHECK:     <dict>
+// CHECK:      <key>kind</key><string>control</string>
+// CHECK:      <key>edges</key>
+// CHECK:       <array>
+// CHECK:        <dict>
+// CHECK:         <key>start</key>
+// CHECK:          <array>
+// CHECK:           <dict>
+// CHECK:            <key>line</key><integer>69</integer>
+// CHECK:            <key>col</key><integer>3</integer>
+// CHECK:            <key>file</key><integer>0</integer>
+// CHECK:           </dict>
+// CHECK:           <dict>
+// CHECK:            <key>line</key><integer>69</integer>
+// CHECK:            <key>col</key><integer>3</integer>
+// CHECK:            <key>file</key><integer>0</integer>
+// CHECK:           </dict>
+// CHECK:          </array>
+// CHECK:         <key>end</key>
+// CHECK:          <array>
+// CHECK:           <dict>
+// CHECK:            <key>line</key><integer>69</integer>
+// CHECK:            <key>col</key><integer>4</integer>
+// CHECK:            <key>file</key><integer>0</integer>
+// CHECK:           </dict>
+// CHECK:           <dict>
+// CHECK:            <key>line</key><integer>69</integer>
+// CHECK:            <key>col</key><integer>10</integer>
+// CHECK:            <key>file</key><integer>0</integer>
+// CHECK:           </dict>
+// CHECK:          </array>
+// CHECK:        </dict>
+// CHECK:       </array>
+// CHECK:     </dict>
+// CHECK:     <dict>
+// CHECK:      <key>kind</key><string>event</string>
+// CHECK:      <key>location</key>
+// CHECK:      <dict>
+// CHECK:       <key>line</key><integer>69</integer>
+// CHECK:       <key>col</key><integer>4</integer>
+// CHECK:       <key>file</key><integer>0</integer>
+// CHECK:      </dict>
+// CHECK:      <key>ranges</key>
+// CHECK:      <array>
+// CHECK:        <array>
+// CHECK:         <dict>
+// CHECK:          <key>line</key><integer>69</integer>
+// CHECK:          <key>col</key><integer>4</integer>
+// CHECK:          <key>file</key><integer>0</integer>
+// CHECK:         </dict>
+// CHECK:         <dict>
+// CHECK:          <key>line</key><integer>69</integer>
+// CHECK:          <key>col</key><integer>12</integer>
+// CHECK:          <key>file</key><integer>0</integer>
+// CHECK:         </dict>
+// CHECK:        </array>
+// CHECK:      </array>
+// CHECK:      <key>depth</key><integer>0</integer>
+// CHECK:      <key>extended_message</key>
+// CHECK:      <string>Calling &apos;getZero&apos;</string>
+// CHECK:      <key>message</key>
+// CHECK: <string>Calling &apos;getZero&apos;</string>
+// CHECK:     </dict>
+// CHECK:     <dict>
+// CHECK:      <key>kind</key><string>event</string>
+// CHECK:      <key>location</key>
+// CHECK:      <dict>
+// CHECK:       <key>line</key><integer>60</integer>
+// CHECK:       <key>col</key><integer>1</integer>
+// CHECK:       <key>file</key><integer>0</integer>
+// CHECK:      </dict>
+// CHECK:      <key>depth</key><integer>1</integer>
+// CHECK:      <key>extended_message</key>
+// CHECK:      <string>Entered call from &apos;testReturnZero&apos;</string>
+// CHECK:      <key>message</key>
+// CHECK: <string>Entered call from &apos;testReturnZero&apos;</string>
+// CHECK:     </dict>
+// CHECK:     <dict>
+// CHECK:      <key>kind</key><string>control</string>
+// CHECK:      <key>edges</key>
+// CHECK:       <array>
+// CHECK:        <dict>
+// CHECK:         <key>start</key>
+// CHECK:          <array>
+// CHECK:           <dict>
+// CHECK:            <key>line</key><integer>60</integer>
+// CHECK:            <key>col</key><integer>1</integer>
+// CHECK:            <key>file</key><integer>0</integer>
+// CHECK:           </dict>
+// CHECK:           <dict>
+// CHECK:            <key>line</key><integer>60</integer>
+// CHECK:            <key>col</key><integer>3</integer>
+// CHECK:            <key>file</key><integer>0</integer>
+// CHECK:           </dict>
+// CHECK:          </array>
+// CHECK:         <key>end</key>
+// CHECK:          <array>
+// CHECK:           <dict>
+// CHECK:            <key>line</key><integer>61</integer>
+// CHECK:            <key>col</key><integer>3</integer>
+// CHECK:            <key>file</key><integer>0</integer>
+// CHECK:           </dict>
+// CHECK:           <dict>
+// CHECK:            <key>line</key><integer>61</integer>
+// CHECK:            <key>col</key><integer>5</integer>
+// CHECK:            <key>file</key><integer>0</integer>
+// CHECK:           </dict>
+// CHECK:          </array>
+// CHECK:        </dict>
+// CHECK:       </array>
+// CHECK:     </dict>
+// CHECK:     <dict>
+// CHECK:      <key>kind</key><string>event</string>
+// CHECK:      <key>location</key>
+// CHECK:      <dict>
+// CHECK:       <key>line</key><integer>61</integer>
+// CHECK:       <key>col</key><integer>3</integer>
+// CHECK:       <key>file</key><integer>0</integer>
+// CHECK:      </dict>
+// CHECK:      <key>ranges</key>
+// CHECK:      <array>
+// CHECK:        <array>
+// CHECK:         <dict>
+// CHECK:          <key>line</key><integer>61</integer>
+// CHECK:          <key>col</key><integer>3</integer>
+// CHECK:          <key>file</key><integer>0</integer>
+// CHECK:         </dict>
+// CHECK:         <dict>
+// CHECK:          <key>line</key><integer>61</integer>
+// CHECK:          <key>col</key><integer>8</integer>
+// CHECK:          <key>file</key><integer>0</integer>
+// CHECK:         </dict>
+// CHECK:        </array>
+// CHECK:      </array>
+// CHECK:      <key>depth</key><integer>1</integer>
+// CHECK:      <key>extended_message</key>
+// CHECK:      <string>Variable &apos;p&apos; initialized to a null pointer value</string>
+// CHECK:      <key>message</key>
+// CHECK: <string>Variable &apos;p&apos; initialized to a null pointer value</string>
+// CHECK:     </dict>
+// CHECK:     <dict>
+// CHECK:      <key>kind</key><string>control</string>
+// CHECK:      <key>edges</key>
+// CHECK:       <array>
+// CHECK:        <dict>
+// CHECK:         <key>start</key>
+// CHECK:          <array>
+// CHECK:           <dict>
+// CHECK:            <key>line</key><integer>61</integer>
+// CHECK:            <key>col</key><integer>3</integer>
+// CHECK:            <key>file</key><integer>0</integer>
+// CHECK:           </dict>
+// CHECK:           <dict>
+// CHECK:            <key>line</key><integer>61</integer>
+// CHECK:            <key>col</key><integer>5</integer>
+// CHECK:            <key>file</key><integer>0</integer>
+// CHECK:           </dict>
+// CHECK:          </array>
+// CHECK:         <key>end</key>
+// CHECK:          <array>
+// CHECK:           <dict>
+// CHECK:            <key>line</key><integer>64</integer>
+// CHECK:            <key>col</key><integer>3</integer>
+// CHECK:            <key>file</key><integer>0</integer>
+// CHECK:           </dict>
+// CHECK:           <dict>
+// CHECK:            <key>line</key><integer>64</integer>
+// CHECK:            <key>col</key><integer>8</integer>
+// CHECK:            <key>file</key><integer>0</integer>
+// CHECK:           </dict>
+// CHECK:          </array>
+// CHECK:        </dict>
+// CHECK:       </array>
+// CHECK:     </dict>
+// CHECK:     <dict>
+// CHECK:      <key>kind</key><string>event</string>
+// CHECK:      <key>location</key>
+// CHECK:      <dict>
+// CHECK:       <key>line</key><integer>64</integer>
+// CHECK:       <key>col</key><integer>3</integer>
+// CHECK:       <key>file</key><integer>0</integer>
+// CHECK:      </dict>
+// CHECK:      <key>ranges</key>
+// CHECK:      <array>
+// CHECK:        <array>
+// CHECK:         <dict>
+// CHECK:          <key>line</key><integer>64</integer>
+// CHECK:          <key>col</key><integer>3</integer>
+// CHECK:          <key>file</key><integer>0</integer>
+// CHECK:         </dict>
+// CHECK:         <dict>
+// CHECK:          <key>line</key><integer>64</integer>
+// CHECK:          <key>col</key><integer>10</integer>
+// CHECK:          <key>file</key><integer>0</integer>
+// CHECK:         </dict>
+// CHECK:        </array>
+// CHECK:      </array>
+// CHECK:      <key>depth</key><integer>1</integer>
+// CHECK:      <key>extended_message</key>
+// CHECK:      <string>Returning null pointer (loaded from &apos;p&apos;)</string>
+// CHECK:      <key>message</key>
+// CHECK: <string>Returning null pointer (loaded from &apos;p&apos;)</string>
+// CHECK:     </dict>
+// CHECK:     <dict>
+// CHECK:      <key>kind</key><string>event</string>
+// CHECK:      <key>location</key>
+// CHECK:      <dict>
+// CHECK:       <key>line</key><integer>69</integer>
+// CHECK:       <key>col</key><integer>4</integer>
+// CHECK:       <key>file</key><integer>0</integer>
+// CHECK:      </dict>
+// CHECK:      <key>ranges</key>
+// CHECK:      <array>
+// CHECK:        <array>
+// CHECK:         <dict>
+// CHECK:          <key>line</key><integer>69</integer>
+// CHECK:          <key>col</key><integer>4</integer>
+// CHECK:          <key>file</key><integer>0</integer>
+// CHECK:         </dict>
+// CHECK:         <dict>
+// CHECK:          <key>line</key><integer>69</integer>
+// CHECK:          <key>col</key><integer>12</integer>
+// CHECK:          <key>file</key><integer>0</integer>
+// CHECK:         </dict>
+// CHECK:        </array>
+// CHECK:      </array>
+// CHECK:      <key>depth</key><integer>1</integer>
+// CHECK:      <key>extended_message</key>
+// CHECK:      <string>Returning from &apos;getZero&apos;</string>
+// CHECK:      <key>message</key>
+// CHECK: <string>Returning from &apos;getZero&apos;</string>
+// CHECK:     </dict>
+// CHECK:     <dict>
+// CHECK:      <key>kind</key><string>control</string>
+// CHECK:      <key>edges</key>
+// CHECK:       <array>
+// CHECK:        <dict>
+// CHECK:         <key>start</key>
+// CHECK:          <array>
+// CHECK:           <dict>
+// CHECK:            <key>line</key><integer>69</integer>
+// CHECK:            <key>col</key><integer>3</integer>
+// CHECK:            <key>file</key><integer>0</integer>
+// CHECK:           </dict>
+// CHECK:           <dict>
+// CHECK:            <key>line</key><integer>69</integer>
+// CHECK:            <key>col</key><integer>3</integer>
+// CHECK:            <key>file</key><integer>0</integer>
+// CHECK:           </dict>
+// CHECK:          </array>
+// CHECK:         <key>end</key>
+// CHECK:          <array>
+// CHECK:           <dict>
+// CHECK:            <key>line</key><integer>69</integer>
+// CHECK:            <key>col</key><integer>4</integer>
+// CHECK:            <key>file</key><integer>0</integer>
+// CHECK:           </dict>
+// CHECK:           <dict>
+// CHECK:            <key>line</key><integer>69</integer>
+// CHECK:            <key>col</key><integer>10</integer>
+// CHECK:            <key>file</key><integer>0</integer>
+// CHECK:           </dict>
+// CHECK:          </array>
+// CHECK:        </dict>
+// CHECK:       </array>
+// CHECK:     </dict>
+// CHECK:     <dict>
+// CHECK:      <key>kind</key><string>control</string>
+// CHECK:      <key>edges</key>
+// CHECK:       <array>
+// CHECK:        <dict>
+// CHECK:         <key>start</key>
+// CHECK:          <array>
+// CHECK:           <dict>
+// CHECK:            <key>line</key><integer>69</integer>
+// CHECK:            <key>col</key><integer>4</integer>
+// CHECK:            <key>file</key><integer>0</integer>
+// CHECK:           </dict>
+// CHECK:           <dict>
+// CHECK:            <key>line</key><integer>69</integer>
+// CHECK:            <key>col</key><integer>10</integer>
+// CHECK:            <key>file</key><integer>0</integer>
+// CHECK:           </dict>
+// CHECK:          </array>
+// CHECK:         <key>end</key>
+// CHECK:          <array>
+// CHECK:           <dict>
+// CHECK:            <key>line</key><integer>69</integer>
+// CHECK:            <key>col</key><integer>3</integer>
+// CHECK:            <key>file</key><integer>0</integer>
+// CHECK:           </dict>
+// CHECK:           <dict>
+// CHECK:            <key>line</key><integer>69</integer>
+// CHECK:            <key>col</key><integer>3</integer>
+// CHECK:            <key>file</key><integer>0</integer>
+// CHECK:           </dict>
+// CHECK:          </array>
+// CHECK:        </dict>
+// CHECK:       </array>
+// CHECK:     </dict>
+// CHECK:     <dict>
+// CHECK:      <key>kind</key><string>event</string>
+// CHECK:      <key>location</key>
+// CHECK:      <dict>
+// CHECK:       <key>line</key><integer>69</integer>
+// CHECK:       <key>col</key><integer>3</integer>
+// CHECK:       <key>file</key><integer>0</integer>
+// CHECK:      </dict>
+// CHECK:      <key>ranges</key>
+// CHECK:      <array>
+// CHECK:        <array>
+// CHECK:         <dict>
+// CHECK:          <key>line</key><integer>69</integer>
+// CHECK:          <key>col</key><integer>3</integer>
+// CHECK:          <key>file</key><integer>0</integer>
+// CHECK:         </dict>
+// CHECK:         <dict>
+// CHECK:          <key>line</key><integer>69</integer>
+// CHECK:          <key>col</key><integer>16</integer>
+// CHECK:          <key>file</key><integer>0</integer>
+// CHECK:         </dict>
+// CHECK:        </array>
+// CHECK:      </array>
+// CHECK:      <key>depth</key><integer>0</integer>
+// CHECK:      <key>extended_message</key>
+// CHECK:      <string>Dereference of null pointer</string>
+// CHECK:      <key>message</key>
+// CHECK: <string>Dereference of null pointer</string>
+// CHECK:     </dict>
+// CHECK:    </array>
+// CHECK:    <key>description</key><string>Dereference of null pointer</string>
+// CHECK:    <key>category</key><string>Logic error</string>
+// CHECK:    <key>type</key><string>Dereference of null pointer</string>
+// CHECK:   <key>issue_context_kind</key><string>function</string>
+// CHECK:   <key>issue_context</key><string>testReturnZero</string>
+// CHECK:   <key>issue_hash</key><integer>1</integer>
+// CHECK:   <key>location</key>
+// CHECK:   <dict>
+// CHECK:    <key>line</key><integer>69</integer>
+// CHECK:    <key>col</key><integer>3</integer>
+// CHECK:    <key>file</key><integer>0</integer>
+// CHECK:   </dict>
+// CHECK:   </dict>
+// CHECK:   <dict>
+// CHECK:    <key>path</key>
+// CHECK:    <array>
+// CHECK:     <dict>
+// CHECK:      <key>kind</key><string>control</string>
+// CHECK:      <key>edges</key>
+// CHECK:       <array>
+// CHECK:        <dict>
+// CHECK:         <key>start</key>
+// CHECK:          <array>
+// CHECK:           <dict>
+// CHECK:            <key>line</key><integer>77</integer>
+// CHECK:            <key>col</key><integer>3</integer>
+// CHECK:            <key>file</key><integer>0</integer>
+// CHECK:           </dict>
+// CHECK:           <dict>
+// CHECK:            <key>line</key><integer>77</integer>
+// CHECK:            <key>col</key><integer>5</integer>
+// CHECK:            <key>file</key><integer>0</integer>
+// CHECK:           </dict>
+// CHECK:          </array>
+// CHECK:         <key>end</key>
+// CHECK:          <array>
+// CHECK:           <dict>
+// CHECK:            <key>line</key><integer>77</integer>
+// CHECK:            <key>col</key><integer>12</integer>
+// CHECK:            <key>file</key><integer>0</integer>
+// CHECK:           </dict>
+// CHECK:           <dict>
+// CHECK:            <key>line</key><integer>77</integer>
+// CHECK:            <key>col</key><integer>18</integer>
+// CHECK:            <key>file</key><integer>0</integer>
+// CHECK:           </dict>
+// CHECK:          </array>
+// CHECK:        </dict>
+// CHECK:       </array>
+// CHECK:     </dict>
+// CHECK:     <dict>
+// CHECK:      <key>kind</key><string>control</string>
+// CHECK:      <key>edges</key>
+// CHECK:       <array>
+// CHECK:        <dict>
+// CHECK:         <key>start</key>
+// CHECK:          <array>
+// CHECK:           <dict>
+// CHECK:            <key>line</key><integer>77</integer>
+// CHECK:            <key>col</key><integer>3</integer>
+// CHECK:            <key>file</key><integer>0</integer>
+// CHECK:           </dict>
+// CHECK:           <dict>
+// CHECK:            <key>line</key><integer>77</integer>
+// CHECK:            <key>col</key><integer>5</integer>
+// CHECK:            <key>file</key><integer>0</integer>
+// CHECK:           </dict>
+// CHECK:          </array>
+// CHECK:         <key>end</key>
+// CHECK:          <array>
+// CHECK:           <dict>
+// CHECK:            <key>line</key><integer>77</integer>
+// CHECK:            <key>col</key><integer>12</integer>
+// CHECK:            <key>file</key><integer>0</integer>
+// CHECK:           </dict>
+// CHECK:           <dict>
+// CHECK:            <key>line</key><integer>77</integer>
+// CHECK:            <key>col</key><integer>18</integer>
+// CHECK:            <key>file</key><integer>0</integer>
+// CHECK:           </dict>
+// CHECK:          </array>
+// CHECK:        </dict>
+// CHECK:       </array>
+// CHECK:     </dict>
+// CHECK:     <dict>
+// CHECK:      <key>kind</key><string>control</string>
+// CHECK:      <key>edges</key>
+// CHECK:       <array>
+// CHECK:        <dict>
+// CHECK:         <key>start</key>
+// CHECK:          <array>
+// CHECK:           <dict>
+// CHECK:            <key>line</key><integer>77</integer>
+// CHECK:            <key>col</key><integer>12</integer>
+// CHECK:            <key>file</key><integer>0</integer>
+// CHECK:           </dict>
+// CHECK:           <dict>
+// CHECK:            <key>line</key><integer>77</integer>
+// CHECK:            <key>col</key><integer>18</integer>
+// CHECK:            <key>file</key><integer>0</integer>
+// CHECK:           </dict>
+// CHECK:          </array>
+// CHECK:         <key>end</key>
+// CHECK:          <array>
+// CHECK:           <dict>
+// CHECK:            <key>line</key><integer>77</integer>
+// CHECK:            <key>col</key><integer>3</integer>
+// CHECK:            <key>file</key><integer>0</integer>
+// CHECK:           </dict>
+// CHECK:           <dict>
+// CHECK:            <key>line</key><integer>77</integer>
+// CHECK:            <key>col</key><integer>5</integer>
+// CHECK:            <key>file</key><integer>0</integer>
+// CHECK:           </dict>
+// CHECK:          </array>
+// CHECK:        </dict>
+// CHECK:       </array>
+// CHECK:     </dict>
+// CHECK:     <dict>
+// CHECK:      <key>kind</key><string>event</string>
+// CHECK:      <key>location</key>
+// CHECK:      <dict>
+// CHECK:       <key>line</key><integer>77</integer>
+// CHECK:       <key>col</key><integer>3</integer>
+// CHECK:       <key>file</key><integer>0</integer>
+// CHECK:      </dict>
+// CHECK:      <key>ranges</key>
+// CHECK:      <array>
+// CHECK:        <array>
+// CHECK:         <dict>
+// CHECK:          <key>line</key><integer>77</integer>
+// CHECK:          <key>col</key><integer>3</integer>
+// CHECK:          <key>file</key><integer>0</integer>
+// CHECK:         </dict>
+// CHECK:         <dict>
+// CHECK:          <key>line</key><integer>77</integer>
+// CHECK:          <key>col</key><integer>8</integer>
+// CHECK:          <key>file</key><integer>0</integer>
+// CHECK:         </dict>
+// CHECK:        </array>
+// CHECK:      </array>
+// CHECK:      <key>depth</key><integer>0</integer>
+// CHECK:      <key>extended_message</key>
+// CHECK:      <string>Variable &apos;a&apos; initialized to a null pointer value</string>
+// CHECK:      <key>message</key>
+// CHECK: <string>Variable &apos;a&apos; initialized to a null pointer value</string>
+// CHECK:     </dict>
+// CHECK:     <dict>
+// CHECK:      <key>kind</key><string>control</string>
+// CHECK:      <key>edges</key>
+// CHECK:       <array>
+// CHECK:        <dict>
+// CHECK:         <key>start</key>
+// CHECK:          <array>
+// CHECK:           <dict>
+// CHECK:            <key>line</key><integer>77</integer>
+// CHECK:            <key>col</key><integer>3</integer>
+// CHECK:            <key>file</key><integer>0</integer>
+// CHECK:           </dict>
+// CHECK:           <dict>
+// CHECK:            <key>line</key><integer>77</integer>
+// CHECK:            <key>col</key><integer>5</integer>
+// CHECK:            <key>file</key><integer>0</integer>
+// CHECK:           </dict>
+// CHECK:          </array>
+// CHECK:         <key>end</key>
+// CHECK:          <array>
+// CHECK:           <dict>
+// CHECK:            <key>line</key><integer>79</integer>
+// CHECK:            <key>col</key><integer>3</integer>
+// CHECK:            <key>file</key><integer>0</integer>
+// CHECK:           </dict>
+// CHECK:           <dict>
+// CHECK:            <key>line</key><integer>79</integer>
+// CHECK:            <key>col</key><integer>3</integer>
+// CHECK:            <key>file</key><integer>0</integer>
+// CHECK:           </dict>
+// CHECK:          </array>
+// CHECK:        </dict>
+// CHECK:       </array>
+// CHECK:     </dict>
+// CHECK:     <dict>
+// CHECK:      <key>kind</key><string>event</string>
+// CHECK:      <key>location</key>
+// CHECK:      <dict>
+// CHECK:       <key>line</key><integer>79</integer>
+// CHECK:       <key>col</key><integer>3</integer>
+// CHECK:       <key>file</key><integer>0</integer>
+// CHECK:      </dict>
+// CHECK:      <key>ranges</key>
+// CHECK:      <array>
+// CHECK:        <array>
+// CHECK:         <dict>
+// CHECK:          <key>line</key><integer>79</integer>
+// CHECK:          <key>col</key><integer>4</integer>
+// CHECK:          <key>file</key><integer>0</integer>
+// CHECK:         </dict>
+// CHECK:         <dict>
+// CHECK:          <key>line</key><integer>79</integer>
+// CHECK:          <key>col</key><integer>4</integer>
+// CHECK:          <key>file</key><integer>0</integer>
+// CHECK:         </dict>
+// CHECK:        </array>
+// CHECK:      </array>
+// CHECK:      <key>depth</key><integer>0</integer>
+// CHECK:      <key>extended_message</key>
+// CHECK:      <string>Dereference of null pointer (loaded from variable &apos;a&apos;)</string>
+// CHECK:      <key>message</key>
+// CHECK: <string>Dereference of null pointer (loaded from variable &apos;a&apos;)</string>
+// CHECK:     </dict>
+// CHECK:    </array>
+// CHECK:    <key>description</key><string>Dereference of null pointer (loaded from variable &apos;a&apos;)</string>
+// CHECK:    <key>category</key><string>Logic error</string>
+// CHECK:    <key>type</key><string>Dereference of null pointer</string>
+// CHECK:   <key>issue_context_kind</key><string>function</string>
+// CHECK:   <key>issue_context</key><string>testInitZero</string>
+// CHECK:   <key>issue_hash</key><integer>4</integer>
+// CHECK:   <key>location</key>
+// CHECK:   <dict>
+// CHECK:    <key>line</key><integer>79</integer>
+// CHECK:    <key>col</key><integer>3</integer>
+// CHECK:    <key>file</key><integer>0</integer>
+// CHECK:   </dict>
+// CHECK:   </dict>
+// CHECK:   <dict>
+// CHECK:    <key>path</key>
+// CHECK:    <array>
+// CHECK:     <dict>
+// CHECK:      <key>kind</key><string>control</string>
+// CHECK:      <key>edges</key>
+// CHECK:       <array>
+// CHECK:        <dict>
+// CHECK:         <key>start</key>
+// CHECK:          <array>
+// CHECK:           <dict>
+// CHECK:            <key>line</key><integer>85</integer>
+// CHECK:            <key>col</key><integer>3</integer>
+// CHECK:            <key>file</key><integer>0</integer>
+// CHECK:           </dict>
+// CHECK:           <dict>
+// CHECK:            <key>line</key><integer>85</integer>
+// CHECK:            <key>col</key><integer>3</integer>
+// CHECK:            <key>file</key><integer>0</integer>
+// CHECK:           </dict>
+// CHECK:          </array>
+// CHECK:         <key>end</key>
+// CHECK:          <array>
+// CHECK:           <dict>
+// CHECK:            <key>line</key><integer>85</integer>
+// CHECK:            <key>col</key><integer>7</integer>
+// CHECK:            <key>file</key><integer>0</integer>
+// CHECK:           </dict>
+// CHECK:           <dict>
+// CHECK:            <key>line</key><integer>85</integer>
+// CHECK:            <key>col</key><integer>13</integer>
+// CHECK:            <key>file</key><integer>0</integer>
+// CHECK:           </dict>
+// CHECK:          </array>
+// CHECK:        </dict>
+// CHECK:       </array>
+// CHECK:     </dict>
+// CHECK:     <dict>
+// CHECK:      <key>kind</key><string>control</string>
+// CHECK:      <key>edges</key>
+// CHECK:       <array>
+// CHECK:        <dict>
+// CHECK:         <key>start</key>
+// CHECK:          <array>
+// CHECK:           <dict>
+// CHECK:            <key>line</key><integer>85</integer>
+// CHECK:            <key>col</key><integer>3</integer>
+// CHECK:            <key>file</key><integer>0</integer>
+// CHECK:           </dict>
+// CHECK:           <dict>
+// CHECK:            <key>line</key><integer>85</integer>
+// CHECK:            <key>col</key><integer>3</integer>
+// CHECK:            <key>file</key><integer>0</integer>
+// CHECK:           </dict>
+// CHECK:          </array>
+// CHECK:         <key>end</key>
+// CHECK:          <array>
+// CHECK:           <dict>
+// CHECK:            <key>line</key><integer>85</integer>
+// CHECK:            <key>col</key><integer>7</integer>
+// CHECK:            <key>file</key><integer>0</integer>
+// CHECK:           </dict>
+// CHECK:           <dict>
+// CHECK:            <key>line</key><integer>85</integer>
+// CHECK:            <key>col</key><integer>13</integer>
+// CHECK:            <key>file</key><integer>0</integer>
+// CHECK:           </dict>
+// CHECK:          </array>
+// CHECK:        </dict>
+// CHECK:       </array>
+// CHECK:     </dict>
+// CHECK:     <dict>
+// CHECK:      <key>kind</key><string>control</string>
+// CHECK:      <key>edges</key>
+// CHECK:       <array>
+// CHECK:        <dict>
+// CHECK:         <key>start</key>
+// CHECK:          <array>
+// CHECK:           <dict>
+// CHECK:            <key>line</key><integer>85</integer>
+// CHECK:            <key>col</key><integer>7</integer>
+// CHECK:            <key>file</key><integer>0</integer>
+// CHECK:           </dict>
+// CHECK:           <dict>
+// CHECK:            <key>line</key><integer>85</integer>
+// CHECK:            <key>col</key><integer>13</integer>
+// CHECK:            <key>file</key><integer>0</integer>
+// CHECK:           </dict>
+// CHECK:          </array>
+// CHECK:         <key>end</key>
+// CHECK:          <array>