Windows support by Ruben Van Boxem.

llvm-svn: 142235
diff --git a/libcxx/include/array b/libcxx/include/array
index 3ac4c55..c11f4bd 100644
--- a/libcxx/include/array
+++ b/libcxx/include/array
@@ -111,7 +111,9 @@
     #include <cassert>
 #endif
 
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
 #pragma GCC system_header
+#endif
 
 _LIBCPP_BEGIN_NAMESPACE_STD