diff --git a/include/boost/predef/hardware.h b/include/boost/predef/hardware.h
index a0cea74..972b73a 100644
--- a/include/boost/predef/hardware.h
+++ b/include/boost/predef/hardware.h
@@ -6,8 +6,10 @@ Distributed under the Boost Software License, Version 1.0.
 http://www.boost.org/LICENSE_1_0.txt)
 */
 
+#if !defined(BOOST_PREDEF_HARDWARE_H) || defined(BOOST_PREDEF_INTERNAL_GENERATE_TESTS)
 #ifndef BOOST_PREDEF_HARDWARE_H
 #define BOOST_PREDEF_HARDWARE_H
+#endif
 
 #include <boost/predef/hardware/simd.h>
 
diff --git a/include/boost/predef/hardware/simd.h b/include/boost/predef/hardware/simd.h
index 253ca57..174eb37 100644
--- a/include/boost/predef/hardware/simd.h
+++ b/include/boost/predef/hardware/simd.h
@@ -6,6 +6,10 @@ Distributed under the Boost Software License, Version 1.0.
 http://www.boost.org/LICENSE_1_0.txt)
 */
 
+#include <boost/predef/hardware/simd/x86.h>
+#include <boost/predef/hardware/simd/arm.h>
+#include <boost/predef/hardware/simd/ppc.h>
+
 #ifndef BOOST_PREDEF_HARDWARE_SIMD_H
 #define BOOST_PREDEF_HARDWARE_SIMD_H
 
@@ -26,10 +30,6 @@ http://www.boost.org/LICENSE_1_0.txt)
      ]
  */
 
-#include <boost/predef/hardware/simd/x86.h>
-#include <boost/predef/hardware/simd/arm.h>
-#include <boost/predef/hardware/simd/ppc.h>
-
 // We check if SIMD extension of multiples architectures have been detected,
 // if yes, then this is an error!
 #if defined(BOOST_HW_SIMD_ARM_AVAILABLE) && defined(BOOST_HW_SIMD_PPC_AVAILABLE) ||\
diff --git a/include/boost/predef/hardware/simd/arm.h b/include/boost/predef/hardware/simd/arm.h
index e0e82a3..fd4d362 100644
--- a/include/boost/predef/hardware/simd/arm.h
+++ b/include/boost/predef/hardware/simd/arm.h
@@ -6,6 +6,9 @@ Distributed under the Boost Software License, Version 1.0.
 http://www.boost.org/LICENSE_1_0.txt)
 */
 
+// From the newest to the oldest
+#include <boost/predef/hardware/simd/arm/neon.h>
+
 #ifndef BOOST_PREDEF_HARDWARE_SIMD_ARM_H
 #define BOOST_PREDEF_HARDWARE_SIMD_ARM_H
 
@@ -27,8 +30,6 @@ http://www.boost.org/LICENSE_1_0.txt)
      ]
  */
 
-#include <boost/predef/hardware/simd/arm/neon.h>
-
 #if defined(BOOST_HW_SIMD_ARM)
 #   define BOOST_HW_SIMD_ARM_AVAILABLE
 #else
diff --git a/include/boost/predef/hardware/simd/ppc.h b/include/boost/predef/hardware/simd/ppc.h
index 91bceb4..1611582 100644
--- a/include/boost/predef/hardware/simd/ppc.h
+++ b/include/boost/predef/hardware/simd/ppc.h
@@ -6,6 +6,11 @@ Distributed under the Boost Software License, Version 1.0.
 http://www.boost.org/LICENSE_1_0.txt)
 */
 
+// From the newest to the oldest
+#include <boost/predef/hardware/simd/ppc/qpx.h>
+#include <boost/predef/hardware/simd/ppc/vsx.h>
+#include <boost/predef/hardware/simd/ppc/vmx.h>
+
 #ifndef BOOST_PREDEF_HARDWARE_SIMD_PPC_H
 #define BOOST_PREDEF_HARDWARE_SIMD_PPC_H
 
@@ -28,11 +33,6 @@ http://www.boost.org/LICENSE_1_0.txt)
      ]
  */
 
-// From the newest to the oldest
-#include <boost/predef/hardware/simd/ppc/qpx.h>
-#include <boost/predef/hardware/simd/ppc/vsx.h>
-#include <boost/predef/hardware/simd/ppc/vmx.h>
-
 #if defined(BOOST_HW_SIMD_PPC)
 #   define BOOST_HW_SIMD_PPC_AVAILABLE
 #else
diff --git a/include/boost/predef/hardware/simd/x86.h b/include/boost/predef/hardware/simd/x86.h
index 1bc4e43..6c281e2 100644
--- a/include/boost/predef/hardware/simd/x86.h
+++ b/include/boost/predef/hardware/simd/x86.h
@@ -6,6 +6,22 @@ Distributed under the Boost Software License, Version 1.0.
 http://www.boost.org/LICENSE_1_0.txt)
 */
 
+// From the newest to the oldest
+#include <boost/predef/hardware/simd/x86/mic.h>   // XEON Phi specific
+#include <boost/predef/hardware/simd/x86/avx2.h>
+#include <boost/predef/hardware/simd/x86/fma3.h>
+#include <boost/predef/hardware/simd/x86/xop.h>   // AMD specific
+#include <boost/predef/hardware/simd/x86/fma4.h>  // AMD specific
+#include <boost/predef/hardware/simd/x86/avx.h>
+#include <boost/predef/hardware/simd/x86/sse4_2.h>
+#include <boost/predef/hardware/simd/x86/sse4_1.h>
+#include <boost/predef/hardware/simd/x86/sse4a.h> // AMD specific
+#include <boost/predef/hardware/simd/x86/ssse3.h>
+#include <boost/predef/hardware/simd/x86/sse3.h>
+#include <boost/predef/hardware/simd/x86/sse2.h>
+#include <boost/predef/hardware/simd/x86/sse.h>
+#include <boost/predef/hardware/simd/x86/mmx.h>
+
 #ifndef BOOST_PREDEF_HARDWARE_SIMD_X86_H
 #define BOOST_PREDEF_HARDWARE_SIMD_X86_H
 
@@ -28,22 +44,6 @@ http://www.boost.org/LICENSE_1_0.txt)
      ]
  */
 
-// From the newest to the oldest
-#include <boost/predef/hardware/simd/x86/mic.h>   // XEON Phi specific
-#include <boost/predef/hardware/simd/x86/avx2.h>
-#include <boost/predef/hardware/simd/x86/fma3.h>
-#include <boost/predef/hardware/simd/x86/xop.h>   // AMD specific
-#include <boost/predef/hardware/simd/x86/fma4.h>  // AMD specific
-#include <boost/predef/hardware/simd/x86/avx.h>
-#include <boost/predef/hardware/simd/x86/sse4_2.h>
-#include <boost/predef/hardware/simd/x86/sse4_1.h>
-#include <boost/predef/hardware/simd/x86/sse4a.h> // AMD specific
-#include <boost/predef/hardware/simd/x86/ssse3.h>
-#include <boost/predef/hardware/simd/x86/sse3.h>
-#include <boost/predef/hardware/simd/x86/sse2.h>
-#include <boost/predef/hardware/simd/x86/sse.h>
-#include <boost/predef/hardware/simd/x86/mmx.h>
-
 #if defined(BOOST_HW_SIMD_X86)
 #   define BOOST_HW_SIMD_X86_AVAILABLE
 #else