Index: cfe/trunk/include/clang/Driver/CC1Options.td
===================================================================
--- cfe/trunk/include/clang/Driver/CC1Options.td
+++ cfe/trunk/include/clang/Driver/CC1Options.td
@@ -166,6 +166,9 @@
 def analyzer_config_compatibility_mode_EQ : Joined<["-"], "analyzer-config-compatibility-mode=">,
   Alias<analyzer_config_compatibility_mode>;
 
+def analyzer_werror : Flag<["-"], "analyzer-werror">,
+  HelpText<"Emit analyzer results as errors rather than warnings">;
+
 //===----------------------------------------------------------------------===//
 // Migrator Options
 //===----------------------------------------------------------------------===//
Index: cfe/trunk/include/clang/StaticAnalyzer/Core/AnalyzerOptions.h
===================================================================
--- cfe/trunk/include/clang/StaticAnalyzer/Core/AnalyzerOptions.h
+++ cfe/trunk/include/clang/StaticAnalyzer/Core/AnalyzerOptions.h
@@ -245,6 +245,9 @@
   /// strategy. We get better code coverage when retry is enabled.
   unsigned NoRetryExhausted : 1;
 
+  /// Emit analyzer warnings as errors.
+  unsigned AnalyzerWerror : 1;
+
   /// The inlining stack depth limit.
   // Cap the stack depth at 4 calls (5 stack frames, base + 4 calls).
   unsigned InlineMaxStackDepth = 5;
@@ -297,7 +300,7 @@
         AnalyzerDisplayProgress(false), AnalyzeNestedBlocks(false),
         eagerlyAssumeBinOpBifurcation(false), TrimGraph(false),
         visualizeExplodedGraphWithGraphViz(false), UnoptimizedCFG(false),
-        PrintStats(false), NoRetryExhausted(false) {
+        PrintStats(false), NoRetryExhausted(false), AnalyzerWerror(false) {
     llvm::sort(AnalyzerConfigCmdFlags);
   }
 
Index: cfe/trunk/lib/Frontend/CompilerInvocation.cpp
===================================================================
--- cfe/trunk/lib/Frontend/CompilerInvocation.cpp
+++ cfe/trunk/lib/Frontend/CompilerInvocation.cpp
@@ -309,6 +309,7 @@
     Args.hasArg(OPT_analyzer_viz_egraph_graphviz);
   Opts.DumpExplodedGraphTo = Args.getLastArgValue(OPT_analyzer_dump_egraph);
   Opts.NoRetryExhausted = Args.hasArg(OPT_analyzer_disable_retry_exhausted);
+  Opts.AnalyzerWerror = Args.hasArg(OPT_analyzer_werror);
   Opts.AnalyzeAll = Args.hasArg(OPT_analyzer_opt_analyze_headers);
   Opts.AnalyzerDisplayProgress = Args.hasArg(OPT_analyzer_display_progress);
   Opts.AnalyzeNestedBlocks =
Index: cfe/trunk/lib/StaticAnalyzer/Frontend/AnalysisConsumer.cpp
===================================================================
--- cfe/trunk/lib/StaticAnalyzer/Frontend/AnalysisConsumer.cpp
+++ cfe/trunk/lib/StaticAnalyzer/Frontend/AnalysisConsumer.cpp
@@ -83,10 +83,11 @@
 namespace {
 class ClangDiagPathDiagConsumer : public PathDiagnosticConsumer {
   DiagnosticsEngine &Diag;
-  bool IncludePath;
+  bool IncludePath, ShouldEmitAsError;
+
 public:
   ClangDiagPathDiagConsumer(DiagnosticsEngine &Diag)
-    : Diag(Diag), IncludePath(false) {}
+      : Diag(Diag), IncludePath(false), ShouldEmitAsError(false) {}
   ~ClangDiagPathDiagConsumer() override {}
   StringRef getName() const override { return "ClangDiags"; }
 
@@ -101,9 +102,14 @@
     IncludePath = true;
   }
 
+  void enableWerror() { ShouldEmitAsError = true; }
+
   void FlushDiagnosticsImpl(std::vector<const PathDiagnostic *> &Diags,
                             FilesMade *filesMade) override {
-    unsigned WarnID = Diag.getCustomDiagID(DiagnosticsEngine::Warning, "%0");
+    unsigned WarnID =
+        ShouldEmitAsError
+            ? Diag.getCustomDiagID(DiagnosticsEngine::Error, "%0")
+            : Diag.getCustomDiagID(DiagnosticsEngine::Warning, "%0");
     unsigned NoteID = Diag.getCustomDiagID(DiagnosticsEngine::Note, "%0");
 
     for (std::vector<const PathDiagnostic*>::iterator I = Diags.begin(),
@@ -225,6 +231,9 @@
           new ClangDiagPathDiagConsumer(PP.getDiagnostics());
       PathConsumers.push_back(clangDiags);
 
+      if (Opts->AnalyzerWerror)
+        clangDiags->enableWerror();
+
       if (Opts->AnalysisDiagOpt == PD_TEXT) {
         clangDiags->enablePaths();
 
@@ -358,7 +367,7 @@
       return true;
 
     llvm::Expected<const VarDecl *> CTUDeclOrError =
-      CTU.getCrossTUDefinition(VD, Opts->CTUDir, Opts->CTUIndexName, 
+      CTU.getCrossTUDefinition(VD, Opts->CTUDir, Opts->CTUIndexName,
                                Opts->DisplayCTUProgress);
 
     if (!CTUDeclOrError) {
Index: cfe/trunk/test/Analysis/override-werror.c
===================================================================
--- cfe/trunk/test/Analysis/override-werror.c
+++ cfe/trunk/test/Analysis/override-werror.c
@@ -1,14 +1,17 @@
 // RUN: %clang_analyze_cc1 -analyzer-checker=core,alpha.core -Werror %s -analyzer-store=region -verify
+// RUN: %clang_analyze_cc1 -analyzer-checker=core,alpha.core -Werror %s -analyzer-store=region -analyzer-werror -verify=werror
 
 // This test case illustrates that using '-analyze' overrides the effect of
 // -Werror.  This allows basic warnings not to interfere with producing
 // analyzer results.
 
-char* f(int *p) { 
-  return p; // expected-warning{{incompatible pointer types}}
+char* f(int *p) {
+  return p; // expected-warning{{incompatible pointer types}} \
+               werror-warning{{incompatible pointer types}}
 }
 
 void g(int *p) {
-  if (!p) *p = 0; // expected-warning{{null}}  
+  if (!p) *p = 0; // expected-warning{{null}} \
+                     werror-error{{null}}
 }