[PATCH] Fix _Unwind_Backtrace for libc++abi built with libgcc.

[Renato Golin]

================
Comment at: src/cxa_personality.cpp:1107
@@ +1106,3 @@
+    bool is_force_unwinding = static_cast<unsigned>(state) & _US_FORCE_UNWIND;
+    state = static_cast<_Unwind_State>(static_cast<unsigned>(state) & ~_US_FORCE_UNWIND);
+
----------------
Why do you need to clear the forced flag?

http://reviews.llvm.org/D7031

EMAIL PREFERENCES
  http://reviews.llvm.org/settings/panel/emailpreferences/