Index: lib/Target/X86/AsmParser/X86AsmParser.cpp
===================================================================
--- lib/Target/X86/AsmParser/X86AsmParser.cpp
+++ lib/Target/X86/AsmParser/X86AsmParser.cpp
@@ -912,6 +912,11 @@
   if (RegNo == 0)
     RegNo = MatchRegisterName(Tok.getString().lower());
 
+  if (isParsingInlineAsm() && isParsingIntelSyntax() && RegNo == X86::EFLAGS) {
+    // Cannot address reg called "flags" in MS inline asm - this is just an identifier!
+    RegNo = 0;
+  }
+
   if (!is64BitMode()) {
     // FIXME: This should be done using Requires<Not64BitMode> and
     // Requires<In64BitMode> so "eiz" usage in 64-bit instructions can be also