Index: tools/driver/cc1as_main.cpp
===================================================================
--- tools/driver/cc1as_main.cpp
+++ tools/driver/cc1as_main.cpp
@@ -33,7 +33,7 @@
 #include "llvm/MC/MCStreamer.h"
 #include "llvm/MC/MCSubtargetInfo.h"
 #include "llvm/MC/MCTargetAsmParser.h"
-#include "llvm/MC/MCTargetOptions.h"
+#include "llvm/MC/MCTargetOptionsCommandFlags.h"
 #include "llvm/Option/Arg.h"
 #include "llvm/Option/ArgList.h"
 #include "llvm/Option/OptTable.h"
@@ -355,6 +355,7 @@
   std::unique_ptr<MCInstrInfo> MCII(TheTarget->createMCInstrInfo());
   std::unique_ptr<MCSubtargetInfo> STI(
       TheTarget->createMCSubtargetInfo(Opts.Triple, Opts.CPU, FS));
+  MCTargetOptions Options = InitMCTargetOptionsFromFlags();
 
   // FIXME: There is a bit of code duplication with addPassesToEmitFile.
   if (Opts.OutputType == AssemblerInvocation::FT_Asm) {
@@ -365,7 +366,7 @@
     MCAsmBackend *MAB = nullptr;
     if (Opts.ShowEncoding) {
       CE = TheTarget->createMCCodeEmitter(*MCII, *MRI, *STI, Ctx);
-      MAB = TheTarget->createMCAsmBackend(*MRI, Opts.Triple, Opts.CPU);
+      MAB = TheTarget->createMCAsmBackend(*MRI, Opts.Triple, Opts.CPU, Options);
     }
     Str.reset(TheTarget->createAsmStreamer(Ctx, *Out, /*asmverbose*/true,
                                            /*useDwarfDirectory*/ true,
@@ -378,7 +379,7 @@
            "Invalid file type!");
     MCCodeEmitter *CE = TheTarget->createMCCodeEmitter(*MCII, *MRI, *STI, Ctx);
     MCAsmBackend *MAB = TheTarget->createMCAsmBackend(*MRI, Opts.Triple,
-                                                      Opts.CPU);
+                                                      Opts.CPU, Options);
     Str.reset(TheTarget->createMCObjectStreamer(Opts.Triple, Ctx, *MAB, *Out,
                                                 CE, *STI, Opts.RelaxAll));
     Str.get()->InitSections(Opts.NoExecStack);
@@ -389,8 +390,6 @@
   std::unique_ptr<MCAsmParser> Parser(
       createMCAsmParser(SrcMgr, Ctx, *Str.get(), *MAI));
 
-  // FIXME: init MCTargetOptions from sanitizer flags here.
-  MCTargetOptions Options;
   std::unique_ptr<MCTargetAsmParser> TAP(
       TheTarget->createMCAsmParser(*STI, *Parser, *MCII, Options));
   if (!TAP)