Index: cfe/trunk/include/clang/Driver/CLCompatOptions.td
===================================================================
--- cfe/trunk/include/clang/Driver/CLCompatOptions.td
+++ cfe/trunk/include/clang/Driver/CLCompatOptions.td
@@ -202,6 +202,7 @@
 def _SLASH_Fo : CLCompileJoined<"Fo">,
   HelpText<"Set output object file, or directory (ends in / or \\)">,
   MetaVarName<"<file or directory>">;
+def _SLASH_GL : CLFlag<"GL">, Alias<flto>;
 def _SLASH_LD : CLFlag<"LD">, HelpText<"Create DLL">;
 def _SLASH_LDd : CLFlag<"LDd">, HelpText<"Create debug DLL">;
 def _SLASH_link : CLRemainingArgs<"link">,
@@ -286,7 +287,6 @@
 def _SLASH_Ge : CLFlag<"Ge">;
 def _SLASH_Gh : CLFlag<"Gh">;
 def _SLASH_GH : CLFlag<"GH">;
-def _SLASH_GL : CLFlag<"GL">;
 def _SLASH_GL_ : CLFlag<"GL-">;
 def _SLASH_Gm : CLFlag<"Gm">;
 def _SLASH_Gm_ : CLFlag<"Gm-">;
Index: cfe/trunk/lib/Driver/Driver.cpp
===================================================================
--- cfe/trunk/lib/Driver/Driver.cpp
+++ cfe/trunk/lib/Driver/Driver.cpp
@@ -1744,7 +1744,7 @@
   // Determine what the derived output name should be.
   const char *NamedOutput;
 
-  if (JA.getType() == types::TY_Object &&
+  if ((JA.getType() == types::TY_Object || JA.getType() == types::TY_LTO_BC) &&
       C.getArgs().hasArg(options::OPT__SLASH_Fo, options::OPT__SLASH_o)) {
     // The /Fo or /o flag decides the object filename.
     StringRef Val = C.getArgs().getLastArg(options::OPT__SLASH_Fo,
Index: cfe/trunk/lib/Driver/Types.cpp
===================================================================
--- cfe/trunk/lib/Driver/Types.cpp
+++ cfe/trunk/lib/Driver/Types.cpp
@@ -45,7 +45,7 @@
 }
 
 const char *types::getTypeTempSuffix(ID Id, bool CLMode) {
-  if (Id == TY_Object && CLMode)
+  if ((Id == TY_Object || Id == TY_LTO_BC) && CLMode)
     return "obj";
   if (Id == TY_Image && CLMode)
     return "exe";
Index: cfe/trunk/test/Driver/cl-outputs.c
===================================================================
--- cfe/trunk/test/Driver/cl-outputs.c
+++ cfe/trunk/test/Driver/cl-outputs.c
@@ -273,3 +273,9 @@
 // RUN: %clang_cl /P /Fifoo.x /obar.x -### -- %s 2>&1 | FileCheck -check-prefix=FioRACE2 %s
 // FioRACE2: "-E"
 // FioRACE2: "-o" "bar.x"
+
+// RUN: %clang_cl /c /GL -### -- %s 2>&1 | FileCheck -check-prefix=LTO-DEFAULT %s
+// LTO-DEFAULT: "-emit-llvm-bc"{{.*}}"-o" "cl-outputs.obj"
+
+// RUN: %clang_cl /c /GL /Fofoo -### -- %s 2>&1 | FileCheck -check-prefix=LTO-FO %s
+// LTO-FO: "-emit-llvm-bc"{{.*}}"-o" "foo.obj"