all-std-headers.cpp: Include the C++11 headers when building with clang

in -std=gnu++11 mode.


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@154654 91177308-0d34-0410-b5e6-96231b3b80d8

INPUTS/all-std-headers.cpp

@@ -52,7 +52,7 @@
 #include <valarray>
 #include <vector>
 
-#if __cplusplus >= 201103
+#if __cplusplus >= 201103 || defined(__GXX_EXPERIMENTAL_CXX0X__)
 #include <array>
 #if __has_include(<atomic>)
 #include <atomic>