Rename GRState::getSVal() -> getRawSVal() and getSimplifiedSVal() -> getSVal().

The end result is now we eagarly constant-fold symbols in the analyzer that are perfectly constrained
to be a constant value.  This allows us to recover some path-sensitivity in some cases by lowering
the required level of reasoning power needed to evaluate some expressions.

The net win from this change is that the false positive in PR 8015 is fixed, and we also
find more idempotent operations bugs.

We do, however, regress with the BugReporterVisitors, which need to be modified to understand
this constant folding (and look past it).  This causes some diagnostic regressions in plist-output.m
which will get addressed in a future patch.  plist-output.m is now marked XFAIL, while
plist-output-alternate.m now tests that the plist output is working, but with the suboptimal
diagnostics.  This second test file will eventually be removed.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@113477 91177308-0d34-0410-b5e6-96231b3b80d8

8 files changed, 782 insertions, 28 deletions

diff --git a/include/clang/Checker/PathSensitive/GRState.h b/include/clang/Checker/PathSensitive/GRState.h
index d72d63ab3c..ac382898d8 100644
--- a/include/clang/Checker/PathSensitive/GRState.h
+++ b/include/clang/Checker/PathSensitive/GRState.h
@@ -270,12 +270,9 @@ public:
   SVal getSValAsScalarOrLoc(const Stmt *Ex) const;
 
   SVal getSVal(Loc LV, QualType T = QualType()) const;
-  
-  /// Returns a "simplified" SVal bound to the location 'LV' in the state's
-  /// store.  A simplified SVal will include optimizations such as
-  /// if the SVal is a symbol whose value is perfectly constrained then that
-  /// constant value is returned instead.
-  SVal getSimplifiedSVal(Loc LV, QualType T= QualType()) const;
+
+  /// Returns the "raw" SVal bound to LV before any value simplfication.
+  SVal getRawSVal(Loc LV, QualType T= QualType()) const;
 
   SVal getSVal(const MemRegion* R) const;
 
@@ -674,7 +671,7 @@ inline SVal GRState::getSValAsScalarOrLoc(const Stmt *S) const {
   return UnknownVal();
 }
 
-inline SVal GRState::getSVal(Loc LV, QualType T) const {
+inline SVal GRState::getRawSVal(Loc LV, QualType T) const {
   return getStateManager().StoreMgr->Retrieve(St, LV, T);
 }
 
diff --git a/lib/Checker/GRExprEngine.cpp b/lib/Checker/GRExprEngine.cpp
index c11785a711..733aebb44d 100644
--- a/lib/Checker/GRExprEngine.cpp
+++ b/lib/Checker/GRExprEngine.cpp
@@ -1876,7 +1876,7 @@ void GRExprEngine::EvalBind(ExplodedNodeSet& Dst, const Stmt* StoreE,
     // is non-NULL.  Checkers typically care about 
     
     GRStmtNodeBuilderRef BuilderRef(Dst, *Builder, *this, *I, newState, StoreE,
-                                    newState != state);
+                                    true);
 
     getTF().EvalBind(BuilderRef, location, Val);
   }
@@ -1970,16 +1970,18 @@ void GRExprEngine::EvalLoadCommon(ExplodedNodeSet& Dst, const Expr *Ex,
   // Proceed with the load.
   for (ExplodedNodeSet::iterator NI=Tmp.begin(), NE=Tmp.end(); NI!=NE; ++NI) {
     state = GetState(*NI);
+
     if (location.isUnknown()) {
       // This is important.  We must nuke the old binding.
       MakeNode(Dst, Ex, *NI, state->BindExpr(Ex, UnknownVal()),
                ProgramPoint::PostLoadKind, tag);
     }
     else {
-      SVal V = state->getSVal(cast<Loc>(location), LoadTy.isNull() ?
-                                                     Ex->getType() : LoadTy);
-      MakeNode(Dst, Ex, *NI, state->BindExpr(Ex, V), ProgramPoint::PostLoadKind,
-               tag);
+      if (LoadTy.isNull())
+        LoadTy = Ex->getType();
+      SVal V = state->getSVal(cast<Loc>(location), LoadTy);
+      MakeNode(Dst, Ex, *NI, state->bindExprAndLocation(Ex, location, V),
+               ProgramPoint::PostLoadKind, tag);
     }
   }
 }
@@ -3384,13 +3386,7 @@ void GRExprEngine::VisitBinaryOperator(const BinaryOperator* B,
         SVal Result = EvalBinOp(state, Op, LeftV, RightV, B->getType());
 
         if (Result.isUnknown()) {
-          if (OldSt != state) {
-            // Generate a new node if we have already created a new state.
-            MakeNode(Tmp3, B, *I2, state);
-          }
-          else
-            Tmp3.Add(*I2);
-
+          MakeNode(Tmp3, B, *I2, state);
           continue;
         }
 
diff --git a/lib/Checker/GRState.cpp b/lib/Checker/GRState.cpp
index d38ae21fce..dbbcb39aa0 100644
--- a/lib/Checker/GRState.cpp
+++ b/lib/Checker/GRState.cpp
@@ -169,9 +169,9 @@ SVal GRState::getSValAsScalarOrLoc(const MemRegion *R) const {
   return UnknownVal();
 }
 
-SVal GRState::getSimplifiedSVal(Loc location, QualType T) const {
-  SVal V = getSVal(cast<Loc>(location), T);
-  
+SVal GRState::getSVal(Loc location, QualType T) const {
+  SVal V = getRawSVal(cast<Loc>(location), T);
+
   // If 'V' is a symbolic value that is *perfectly* constrained to
   // be a constant value, use that value instead to lessen the burden
   // on later analysis stages (so we have less symbolic values to reason
diff --git a/lib/Checker/IdempotentOperationChecker.cpp b/lib/Checker/IdempotentOperationChecker.cpp
index 3d454bed9a..3dcbea491e 100644
--- a/lib/Checker/IdempotentOperationChecker.cpp
+++ b/lib/Checker/IdempotentOperationChecker.cpp
@@ -200,7 +200,7 @@ void IdempotentOperationChecker::PreVisitBinaryOperator(
       A = Impossible;
       return;
     }
-    LHSVal = state->getSVal(cast<Loc>(LHSVal));
+    LHSVal = state->getSVal(cast<Loc>(LHSVal), LHS->getType());
   }
 
 
@@ -355,6 +355,8 @@ void IdempotentOperationChecker::PostVisitBinaryOperator(
                                                       const BinaryOperator *B) {
   // Add the ExplodedNode we just visited
   BinaryOperatorData &Data = hash[B];
+  assert(isa<BinaryOperator>(cast<StmtPoint>(C.getPredecessor()
+                                             ->getLocation()).getStmt()));
   Data.explodedNodes.Add(C.getPredecessor());
 }
 
diff --git a/test/Analysis/dead-stores.c b/test/Analysis/dead-stores.c
index da131a2982..c150fa088d 100644
--- a/test/Analysis/dead-stores.c
+++ b/test/Analysis/dead-stores.c
@@ -150,7 +150,7 @@ void f15(unsigned x, unsigned y) {
 
 int f16(int x) {
   x = x * 2;
-  x = sizeof(int [x = (x || x + 1) * 2]) // expected-warning{{Although the value stored to 'x' is used}} expected-warning{{The left operand to '*' is always 1}}
+  x = sizeof(int [x = (x || x + 1) * 2]) // expected-warning{{Although the value stored to 'x' is used}} expected-warning{{The left operand to '*' is always 1}} expected-warning{{The left operand to '+' is always 0}}
       ? 5 : 8;
   return x;
 }
diff --git a/test/Analysis/misc-ps-region-store.m b/test/Analysis/misc-ps-region-store.m
index a4e0d0bfa6..27aaff09e2 100644
--- a/test/Analysis/misc-ps-region-store.m
+++ b/test/Analysis/misc-ps-region-store.m
@@ -1103,16 +1103,18 @@ void pr8015_C() {
   }
 }
 
-// FIXME: This is a false positive due to not reasoning about symbolic
-// array indices correctly.  Discussion in PR 8015.
+// Tests that we correctly handle that 'number' is perfectly constrained
+// after 'if (nunber == 0)', allowing us to resolve that
+// numbers[number] == numbers[0].
 void pr8015_D_FIXME() {
   int number = pr8015_A();
   const char *numbers[] = { "zero" };
   if (number == 0) {
-    if (numbers[number] == numbers[0])
+    if (numbers[number] == numbers[0]) // expected-warning{{Both operands to '==' always have the same value}}
       return;
+    // Unreachable.
     int *p = 0;
-    *p = 0xDEADBEEF; // expected-warning{{Dereference of null pointer}}
+    *p = 0xDEADBEEF; // no-warnng
   }
 }
 
diff --git a/test/Analysis/plist-output-alternate.m b/test/Analysis/plist-output-alternate.m
new file mode 100644
index 0000000000..ad9f89fcd1
--- /dev/null
+++ b/test/Analysis/plist-output-alternate.m
@@ -0,0 +1,756 @@
+// RUN: %clang_cc1 -analyze -analyzer-experimental-internal-checks -analyzer-check-objc-mem -analyzer-store=region -analyzer-constraints=range -fblocks -analyzer-output=plist -o - %s | FileCheck %s
+
+void test_null_init(void) {
+  int *p = 0;
+  *p = 0xDEADBEEF;
+}
+
+void test_null_assign(void) {
+  int *p;
+  p = 0;
+  *p = 0xDEADBEEF;
+}
+
+void test_null_assign_transitive(void) {
+  int *p;
+  p = 0;
+  int *q = p;
+  *q = 0xDEADBEEF;
+}
+
+void test_null_cond(int *p) {
+  if (!p) {
+    *p = 0xDEADBEEF;
+  }
+}
+
+void test_null_cond_transitive(int *q) {
+  if (!q) {
+    int *p = q;
+    *p = 0xDEADBEEF;
+  }
+}
+
+void test_null_field(void) {
+  struct s { int *p; } x;
+  x.p = 0;
+  *(x.p) = 0xDEADBEEF;
+}
+
+// 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">
+// CHECK: <dict>
+// CHECK:  <key>files</key>
+// CHECK:  <array>
+// CHECK:  </array>
+// CHECK:  <key>diagnostics</key>
+// CHECK:  <array>
+// CHECK:   <dict>
+// CHECK:    <key>path</key>
+// CHECK:    <array>
+// CHECK:     <dict>
+// CHECK:      <key>kind</key><string>event</string>
+// CHECK:      <key>location</key>
+// CHECK:      <dict>
+// CHECK:       <key>line</key><integer>4</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>4</integer>
+// CHECK:          <key>col</key><integer>3</integer>
+// CHECK:          <key>file</key><integer>0</integer>
+// CHECK:         </dict>
+// CHECK:         <dict>
+// CHECK:          <key>line</key><integer>4</integer>
+// CHECK:          <key>col</key><integer>8</integer>
+// CHECK:          <key>file</key><integer>0</integer>
+// CHECK:         </dict>
+// CHECK:        </array>
+// CHECK:      </array>
+// 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>4</integer>
+// CHECK:            <key>col</key><integer>3</integer>
+// CHECK:            <key>file</key><integer>0</integer>
+// CHECK:           </dict>
+// CHECK:           <dict>
+// CHECK:            <key>line</key><integer>4</integer>
+// CHECK:            <key>col</key><integer>8</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>5</integer>
+// CHECK:            <key>col</key><integer>3</integer>
+// CHECK:            <key>file</key><integer>0</integer>
+// CHECK:           </dict>
+// CHECK:           <dict>
+// CHECK:            <key>line</key><integer>5</integer>
+// CHECK:            <key>col</key><integer>4</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>5</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>5</integer>
+// CHECK:          <key>col</key><integer>4</integer>
+// CHECK:          <key>file</key><integer>0</integer>
+// CHECK:         </dict>
+// CHECK:         <dict>
+// CHECK:          <key>line</key><integer>5</integer>
+// CHECK:          <key>col</key><integer>4</integer>
+// CHECK:          <key>file</key><integer>0</integer>
+// CHECK:         </dict>
+// CHECK:        </array>
+// CHECK:      </array>
+// CHECK:      <key>extended_message</key>
+// CHECK:      <string>Dereference of null pointer (loaded from variable &apos;p&apos;)</string>
+// CHECK:      <key>message</key>
+// CHECK: <string>Dereference of null pointer (loaded from variable &apos;p&apos;)</string>
+// CHECK:     </dict>
+// CHECK:    </array>
+// CHECK:    <key>description</key><string>Dereference of null pointer (loaded from variable &apos;p&apos;)</string>
+// CHECK:    <key>category</key><string>Logic error</string>
+// CHECK:    <key>type</key><string>Dereference of null pointer</string>
+// CHECK:   <key>location</key>
+// CHECK:   <dict>
+// CHECK:    <key>line</key><integer>5</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>9</integer>
+// CHECK:            <key>col</key><integer>3</integer>
+// CHECK:            <key>file</key><integer>0</integer>
+// CHECK:           </dict>
+// CHECK:           <dict>
+// CHECK:            <key>line</key><integer>9</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>10</integer>
+// CHECK:            <key>col</key><integer>3</integer>
+// CHECK:            <key>file</key><integer>0</integer>
+// CHECK:           </dict>
+// CHECK:           <dict>
+// CHECK:            <key>line</key><integer>10</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>10</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>10</integer>
+// CHECK:          <key>col</key><integer>3</integer>
+// CHECK:          <key>file</key><integer>0</integer>
+// CHECK:         </dict>
+// CHECK:         <dict>
+// CHECK:          <key>line</key><integer>10</integer>
+// CHECK:          <key>col</key><integer>7</integer>
+// CHECK:          <key>file</key><integer>0</integer>
+// CHECK:         </dict>
+// CHECK:        </array>
+// CHECK:      </array>
+// CHECK:      <key>extended_message</key>
+// CHECK:      <string>Null pointer value stored to &apos;p&apos;</string>
+// CHECK:      <key>message</key>
+// CHECK: <string>Null pointer value stored to &apos;p&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>10</integer>
+// CHECK:            <key>col</key><integer>3</integer>
+// CHECK:            <key>file</key><integer>0</integer>
+// CHECK:           </dict>
+// CHECK:           <dict>
+// CHECK:            <key>line</key><integer>10</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>11</integer>
+// CHECK:            <key>col</key><integer>3</integer>
+// CHECK:            <key>file</key><integer>0</integer>
+// CHECK:           </dict>
+// CHECK:           <dict>
+// CHECK:            <key>line</key><integer>11</integer>
+// CHECK:            <key>col</key><integer>4</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>11</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>11</integer>
+// CHECK:          <key>col</key><integer>4</integer>
+// CHECK:          <key>file</key><integer>0</integer>
+// CHECK:         </dict>
+// CHECK:         <dict>
+// CHECK:          <key>line</key><integer>11</integer>
+// CHECK:          <key>col</key><integer>4</integer>
+// CHECK:          <key>file</key><integer>0</integer>
+// CHECK:         </dict>
+// CHECK:        </array>
+// CHECK:      </array>
+// CHECK:      <key>extended_message</key>
+// CHECK:      <string>Dereference of null pointer (loaded from variable &apos;p&apos;)</string>
+// CHECK:      <key>message</key>
+// CHECK: <string>Dereference of null pointer (loaded from variable &apos;p&apos;)</string>
+// CHECK:     </dict>
+// CHECK:    </array>
+// CHECK:    <key>description</key><string>Dereference of null pointer (loaded from variable &apos;p&apos;)</string>
+// CHECK:    <key>category</key><string>Logic error</string>
+// CHECK:    <key>type</key><string>Dereference of null pointer</string>
+// CHECK:   <key>location</key>
+// CHECK:   <dict>
+// CHECK:    <key>line</key><integer>11</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>15</integer>
+// CHECK:            <key>col</key><integer>3</integer>
+// CHECK:            <key>file</key><integer>0</integer>
+// CHECK:           </dict>
+// CHECK:           <dict>
+// CHECK:            <key>line</key><integer>15</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>17</integer>
+// CHECK:            <key>col</key><integer>3</integer>
+// CHECK:            <key>file</key><integer>0</integer>
+// CHECK:           </dict>
+// CHECK:           <dict>
+// CHECK:            <key>line</key><integer>17</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>17</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>17</integer>
+// CHECK:          <key>col</key><integer>3</integer>
+// CHECK:          <key>file</key><integer>0</integer>
+// CHECK:         </dict>
+// CHECK:         <dict>
+// CHECK:          <key>line</key><integer>17</integer>
+// CHECK:          <key>col</key><integer>8</integer>
+// CHECK:          <key>file</key><integer>0</integer>
+// CHECK:         </dict>
+// CHECK:        </array>
+// CHECK:      </array>
+// CHECK:      <key>extended_message</key>
+// CHECK:      <string>Variable &apos;q&apos; initialized to a null pointer value</string>
+// CHECK:      <key>message</key>
+// CHECK: <string>Variable &apos;q&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>17</integer>
+// CHECK:            <key>col</key><integer>3</integer>
+// CHECK:            <key>file</key><integer>0</integer>
+// CHECK:           </dict>
+// CHECK:           <dict>
+// CHECK:            <key>line</key><integer>17</integer>
+// CHECK:            <key>col</key><integer>8</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>18</integer>
+// CHECK:            <key>col</key><integer>3</integer>
+// CHECK:            <key>file</key><integer>0</integer>
+// CHECK:           </dict>
+// CHECK:           <dict>
+// CHECK:            <key>line</key><integer>18</integer>
+// CHECK:            <key>col</key><integer>4</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>18</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>18</integer>
+// CHECK:          <key>col</key><integer>4</integer>
+// CHECK:          <key>file</key><integer>0</integer>
+// CHECK:         </dict>
+// CHECK:         <dict>
+// CHECK:          <key>line</key><integer>18</integer>
+// CHECK:          <key>col</key><integer>4</integer>
+// CHECK:          <key>file</key><integer>0</integer>
+// CHECK:         </dict>
+// CHECK:        </array>
+// CHECK:      </array>
+// CHECK:      <key>extended_message</key>
+// CHECK:      <string>Dereference of null pointer (loaded from variable &apos;q&apos;)</string>
+// CHECK:      <key>message</key>
+// CHECK: <string>Dereference of null pointer (loaded from variable &apos;q&apos;)</string>
+// CHECK:     </dict>
+// CHECK:    </array>
+// CHECK:    <key>description</key><string>Dereference of null pointer (loaded from variable &apos;q&apos;)</string>
+// CHECK:    <key>category</key><string>Logic error</string>
+// CHECK:    <key>type</key><string>Dereference of null pointer</string>
+// CHECK:   <key>location</key>
+// CHECK:   <dict>
+// CHECK:    <key>line</key><integer>18</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>22</integer>
+// CHECK:            <key>col</key><integer>3</integer>
+// CHECK:            <key>file</key><integer>0</integer>
+// CHECK:           </dict>
+// CHECK:           <dict>
+// CHECK:            <key>line</key><integer>22</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>23</integer>
+// CHECK:            <key>col</key><integer>5</integer>
+// CHECK:            <key>file</key><integer>0</integer>
+// CHECK:           </dict>
+// CHECK:           <dict>
+// CHECK:            <key>line</key><integer>23</integer>
+// CHECK:            <key>col</key><integer>6</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>23</integer>
+// CHECK:       <key>col</key><integer>5</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>23</integer>
+// CHECK:          <key>col</key><integer>6</integer>
+// CHECK:          <key>file</key><integer>0</integer>
+// CHECK:         </dict>
+// CHECK:         <dict>
+// CHECK:          <key>line</key><integer>23</integer>
+// CHECK:          <key>col</key><integer>6</integer>
+// CHECK:          <key>file</key><integer>0</integer>
+// CHECK:         </dict>
+// CHECK:        </array>
+// CHECK:      </array>
+// CHECK:      <key>extended_message</key>
+// CHECK:      <string>Dereference of null pointer (loaded from variable &apos;p&apos;)</string>
+// CHECK:      <key>message</key>
+// CHECK: <string>Dereference of null pointer (loaded from variable &apos;p&apos;)</string>
+// CHECK:     </dict>
+// CHECK:    </array>
+// CHECK:    <key>description</key><string>Dereference of null pointer (loaded from variable &apos;p&apos;)</string>
+// CHECK:    <key>category</key><string>Logic error</string>
+// CHECK:    <key>type</key><string>Dereference of null pointer</string>
+// CHECK:   <key>location</key>
+// CHECK:   <dict>
+// CHECK:    <key>line</key><integer>23</integer>
+// CHECK:    <key>col</key><integer>5</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>28</integer>
+// CHECK:            <key>col</key><integer>3</integer>
+// CHECK:            <key>file</key><integer>0</integer>
+// CHECK:           </dict>
+// CHECK:           <dict>
+// CHECK:            <key>line</key><integer>28</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>29</integer>
+// CHECK:            <key>col</key><integer>5</integer>
+// CHECK:            <key>file</key><integer>0</integer>
+// CHECK:           </dict>
+// CHECK:           <dict>
+// CHECK:            <key>line</key><integer>29</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>29</integer>
+// CHECK:       <key>col</key><integer>5</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>29</integer>
+// CHECK:          <key>col</key><integer>5</integer>
+// CHECK:          <key>file</key><integer>0</integer>
+// CHECK:         </dict>
+// CHECK:         <dict>
+// CHECK:          <key>line</key><integer>29</integer>
+// CHECK:          <key>col</key><integer>10</integer>
+// CHECK:          <key>file</key><integer>0</integer>
+// CHECK:         </dict>
+// CHECK:        </array>
+// CHECK:      </array>
+// 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>29</integer>
+// CHECK:            <key>col</key><integer>5</integer>
+// CHECK:            <key>file</key><integer>0</integer>
+// CHECK:           </dict>
+// CHECK:           <dict>
+// CHECK:            <key>line</key><integer>29</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>30</integer>
+// CHECK:            <key>col</key><integer>5</integer>