diff --git a/lib/Driver/Tools.cpp b/lib/Driver/Tools.cpp
index afb22a2..29dd3f5 100644
--- a/lib/Driver/Tools.cpp
+++ b/lib/Driver/Tools.cpp
@@ -1213,7 +1213,7 @@
     }
   }
 
-  RenderExtraToolArgs(CmdArgs);
+  RenderExtraToolArgs(JA, CmdArgs);
 
   // If using a driver driver, force the arch.
   const std::string &Arch = getToolChain().getArchName();
@@ -1291,23 +1291,32 @@
   Dest.addCommand(new Command(JA, *this, Exec, CmdArgs));
 }
 
-void gcc::Preprocess::RenderExtraToolArgs(ArgStringList &CmdArgs) const {
+void gcc::Preprocess::RenderExtraToolArgs(const JobAction &JA,
+                                          ArgStringList &CmdArgs) const {
   CmdArgs.push_back("-E");
 }
 
-void gcc::Precompile::RenderExtraToolArgs(ArgStringList &CmdArgs) const {
+void gcc::Precompile::RenderExtraToolArgs(const JobAction &JA,
+                                          ArgStringList &CmdArgs) const {
   // The type is good enough.
 }
 
-void gcc::Compile::RenderExtraToolArgs(ArgStringList &CmdArgs) const {
-  CmdArgs.push_back("-S");
+void gcc::Compile::RenderExtraToolArgs(const JobAction &JA,
+                                       ArgStringList &CmdArgs) const {
+  // If -flto, etc. are present then make sure not to force assembly output.
+  if (JA.getType() == types::TY_LLVMBC)
+    CmdArgs.push_back("-c");
+  else
+    CmdArgs.push_back("-S");
 }
 
-void gcc::Assemble::RenderExtraToolArgs(ArgStringList &CmdArgs) const {
+void gcc::Assemble::RenderExtraToolArgs(const JobAction &JA,
+                                        ArgStringList &CmdArgs) const {
   CmdArgs.push_back("-c");
 }
 
-void gcc::Link::RenderExtraToolArgs(ArgStringList &CmdArgs) const {
+void gcc::Link::RenderExtraToolArgs(const JobAction &JA,
+                                    ArgStringList &CmdArgs) const {
   // The types are (hopefully) good enough.
 }
 
diff --git a/lib/Driver/Tools.h b/lib/Driver/Tools.h
index abd8cfc..572c7f4 100644
--- a/lib/Driver/Tools.h
+++ b/lib/Driver/Tools.h
@@ -66,7 +66,8 @@
 
     /// RenderExtraToolArgs - Render any arguments necessary to force
     /// the particular tool mode.
-    virtual void RenderExtraToolArgs(ArgStringList &CmdArgs) const = 0;
+    virtual void RenderExtraToolArgs(const JobAction &JA,
+                                     ArgStringList &CmdArgs) const = 0;
   };
 
 
@@ -78,7 +79,8 @@
     virtual bool canPipeOutput() const { return true; }
     virtual bool hasIntegratedCPP() const { return false; }
 
-    virtual void RenderExtraToolArgs(ArgStringList &CmdArgs) const;
+    virtual void RenderExtraToolArgs(const JobAction &JA,
+                                     ArgStringList &CmdArgs) const;
   };
 
   class VISIBILITY_HIDDEN Precompile : public Common  {
@@ -89,7 +91,8 @@
     virtual bool canPipeOutput() const { return false; }
     virtual bool hasIntegratedCPP() const { return true; }
 
-    virtual void RenderExtraToolArgs(ArgStringList &CmdArgs) const;
+    virtual void RenderExtraToolArgs(const JobAction &JA,
+                                     ArgStringList &CmdArgs) const;
   };
 
   class VISIBILITY_HIDDEN Compile : public Common  {
@@ -100,7 +103,8 @@
     virtual bool canPipeOutput() const { return true; }
     virtual bool hasIntegratedCPP() const { return true; }
 
-    virtual void RenderExtraToolArgs(ArgStringList &CmdArgs) const;
+    virtual void RenderExtraToolArgs(const JobAction &JA,
+                                     ArgStringList &CmdArgs) const;
   };
 
   class VISIBILITY_HIDDEN Assemble : public Common  {
@@ -111,7 +115,8 @@
     virtual bool canPipeOutput() const { return false; }
     virtual bool hasIntegratedCPP() const { return false; }
 
-    virtual void RenderExtraToolArgs(ArgStringList &CmdArgs) const;
+    virtual void RenderExtraToolArgs(const JobAction &JA,
+                                     ArgStringList &CmdArgs) const;
   };
 
   class VISIBILITY_HIDDEN Link : public Common  {
@@ -122,7 +127,8 @@
     virtual bool canPipeOutput() const { return false; }
     virtual bool hasIntegratedCPP() const { return false; }
 
-    virtual void RenderExtraToolArgs(ArgStringList &CmdArgs) const;
+    virtual void RenderExtraToolArgs(const JobAction &JA,
+                                     ArgStringList &CmdArgs) const;
   };
 } // end namespace gcc