diff --git a/clang/lib/Driver/ToolChains/Arch/X86.cpp b/clang/lib/Driver/ToolChains/Arch/X86.cpp
--- a/clang/lib/Driver/ToolChains/Arch/X86.cpp
+++ b/clang/lib/Driver/ToolChains/Arch/X86.cpp
@@ -102,6 +102,12 @@
   if (Is64Bit)
     return "x86-64";
 
+  if (Triple.getArchName() == "i686")
+    return "i686";
+
+  if (Triple.getArchName() == "i786")
+    return "pentiumpro"
+
   switch (Triple.getOS()) {
   case llvm::Triple::NetBSD:
     return "i486";