[PATCH] [x32] Add X32 support to driver

[Simon Atanasyan]

LGTM

================
Comment at: lib/Driver/ToolChains.cpp:1963
@@ -1949,1 +1962,3 @@
+  enum { UNKNOWN, WANT32, WANT64, WANTX32 } Want = UNKNOWN;
+  const bool isX32 {TargetTriple.getEnvironment() == llvm::Triple::GNUX32};
   if (TargetTriple.isArch32Bit() && !NonExistent(Alt32))
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s/isX32/IsX32/

http://reviews.llvm.org/D4180