Index: tools/clang/include/clang/Frontend/VerifyDiagnosticConsumer.h
==================================================================
--- tools/clang/include/clang/Frontend/VerifyDiagnosticConsumer.h
+++ tools/clang/include/clang/Frontend/VerifyDiagnosticConsumer.h
@@ -133,11 +133,14 @@
 
   protected:
     Directive(SourceLocation DirectiveLoc, SourceLocation DiagnosticLoc,
               StringRef Text, unsigned Min, unsigned Max)
       : DirectiveLoc(DirectiveLoc), DiagnosticLoc(DiagnosticLoc),
-        Text(Text), Min(Min), Max(Max) { }
+        Text(Text), Min(Min), Max(Max) {
+    assert(!DirectiveLoc.isInvalid() && "DirectiveLoc is invalid!");
+    assert(!DiagnosticLoc.isInvalid() && "DiagnosticLoc is invalid!");
+    }
 
   private:
     Directive(const Directive&); // DO NOT IMPLEMENT
     void operator=(const Directive&); // DO NOT IMPLEMENT
   };

Index: tools/clang/lib/Frontend/VerifyDiagnosticConsumer.cpp
==================================================================
--- tools/clang/lib/Frontend/VerifyDiagnosticConsumer.cpp
+++ tools/clang/lib/Frontend/VerifyDiagnosticConsumer.cpp
@@ -372,19 +372,16 @@
     ParseDirective(&Comment[0], Comment.size(), ED, SM, Tok.getLocation(),
                    PP.getDiagnostics());
   };
 }
 
-/// PrintProblem - This takes a diagnostic map of the delta between expected and
-/// seen diagnostics. If there's anything in it, then something unexpected
-/// happened. Print the map out in a nice format and return "true". If the map
-/// is empty and we're not going to print things, then return "false".
-///
-static unsigned PrintProblem(DiagnosticsEngine &Diags, SourceManager *SourceMgr,
-                             const_diag_iterator diag_begin,
-                             const_diag_iterator diag_end,
-                             const char *Kind, bool Expected) {
+/// \brief Takes a list of diagnostics that have been generated but not matched
+/// by an expected-* directive and produces a diagnostic to the user from this.
+static unsigned PrintUnexpected(DiagnosticsEngine &Diags, SourceManager *SourceMgr,
+                                const_diag_iterator diag_begin,
+                                const_diag_iterator diag_end,
+                                const char *Kind) {
   if (diag_begin == diag_end) return 0;
 
   SmallString<256> Fmt;
   llvm::raw_svector_ostream OS(Fmt);
   for (const_diag_iterator I = diag_begin, E = diag_end; I != E; ++I) {
@@ -394,37 +391,35 @@
       OS << "\n  Line " << SourceMgr->getPresumedLineNumber(I->first);
     OS << ": " << I->second;
   }
 
   Diags.Report(diag::err_verify_inconsistent_diags)
-    << Kind << !Expected << OS.str();
+    << Kind << /*Unexpected=*/true << OS.str();
   return std::distance(diag_begin, diag_end);
 }
 
-static unsigned PrintProblem(DiagnosticsEngine &Diags, SourceManager *SourceMgr,
-                             DirectiveList &DL, const char *Kind,
-                             bool Expected) {
+/// \brief Takes a list of diagnostics that were expected to have been generated
+/// but were not and produces a diagnostic to the user from this.
+static unsigned PrintExpected(DiagnosticsEngine &Diags, SourceManager &SourceMgr,
+                              DirectiveList &DL, const char *Kind) {
   if (DL.empty())
     return 0;
 
   SmallString<256> Fmt;
   llvm::raw_svector_ostream OS(Fmt);
   for (DirectiveList::iterator I = DL.begin(), E = DL.end(); I != E; ++I) {
-    Directive& D = **I;
-    if (D.DiagnosticLoc.isInvalid() || !SourceMgr)
-      OS << "\n  (frontend)";
-    else
-      OS << "\n  Line " << SourceMgr->getPresumedLineNumber(D.DiagnosticLoc);
-    if (!D.DirectiveLoc.isInvalid() && D.DirectiveLoc != D.DiagnosticLoc)
+    Directive &D = **I;
+    OS << "\n  Line " << SourceMgr.getPresumedLineNumber(D.DiagnosticLoc);
+    if (D.DirectiveLoc != D.DiagnosticLoc)
       OS << " (directive at "
-         << SourceMgr->getFilename(D.DirectiveLoc) << ":"
-         << SourceMgr->getPresumedLineNumber(D.DirectiveLoc) << ")";
+         << SourceMgr.getFilename(D.DirectiveLoc) << ":"
+         << SourceMgr.getPresumedLineNumber(D.DirectiveLoc) << ")";
     OS << ": " << D.Text;
   }
 
   Diags.Report(diag::err_verify_inconsistent_diags)
-    << Kind << !Expected << OS.str();
+    << Kind << /*Unexpected=*/false << OS.str();
   return DL.size();
 }
 
 /// CheckLists - Compare expected to seen diagnostic lists and return the
 /// the difference between them.
@@ -461,13 +456,12 @@
         Right.erase(II);
       }
     }
   }
   // Now all that's left in Right are those that were not matched.
-  unsigned num = PrintProblem(Diags, &SourceMgr, LeftOnly, Label, true);
-  num += PrintProblem(Diags, &SourceMgr, Right.begin(), Right.end(),
-                      Label, false);
+  unsigned num = PrintExpected(Diags, SourceMgr, LeftOnly, Label);
+  num += PrintUnexpected(Diags, &SourceMgr, Right.begin(), Right.end(), Label);
   return num;
 }
 
 /// CheckResults - This compares the expected results to those that
 /// were actually reported. It emits any discrepencies. Return "true" if there
@@ -523,19 +517,16 @@
     }
 
     // Check that the expected diagnostics occurred.
     NumErrors += CheckResults(Diags, SM, *Buffer, ED);
   } else {
-    NumErrors += (PrintProblem(Diags, 0,
-                               Buffer->err_begin(), Buffer->err_end(),
-                               "error", false) +
-                  PrintProblem(Diags, 0,
-                               Buffer->warn_begin(), Buffer->warn_end(),
-                               "warn", false) +
-                  PrintProblem(Diags, 0,
-                               Buffer->note_begin(), Buffer->note_end(),
-                               "note", false));
+    NumErrors += (PrintUnexpected(Diags, 0, Buffer->err_begin(),
+                                  Buffer->err_end(), "error") +
+                  PrintUnexpected(Diags, 0, Buffer->warn_begin(),
+                                  Buffer->warn_end(), "warn") +
+                  PrintUnexpected(Diags, 0, Buffer->note_begin(),
+                                  Buffer->note_end(), "note"));
   }
 
   Diags.takeClient();
   Diags.setClient(CurClient, OwnsCurClient);