Fix <rdar://problem/10217868>.

llvm-svn: 140907

libcxx/include/memory

@@ -2903,9 +2903,7 @@ public:
     long use_count() const _NOEXCEPT {return __shared_count::use_count();}
     __shared_weak_count* lock() _NOEXCEPT;
 
-#ifndef _LIBCPP_NO_RTTI
     virtual const void* __get_deleter(const type_info&) const _NOEXCEPT;
-#endif
 private:
     virtual void __on_zero_shared_weak() _NOEXCEPT = 0;
 };