WRG: -Wheader-guard is clang specific

Modules/Learning/Supervised/include/otbSharkRandomForestsMachineLearningModel.h

@@ -33,8 +33,10 @@
 #pragma GCC diagnostic ignored "-Wsign-compare"
 #pragma GCC diagnostic ignored "-Wcast-align"
 #pragma GCC diagnostic ignored "-Wunknown-pragmas"
-#pragma GCC diagnostic ignored "-Wheader-guard"
 #pragma GCC diagnostic ignored "-Wmissing-field-initializers"
+#if defined(__clang__)
+#pragma clang diagnostic ignored "-Wheader-guard"
+#endif
 #endif
 #include <shark/Models/Classifier.h>
 #include "otb_shark.h"

Modules/ThirdParty/Shark/include/otbSharkUtils.h

@@ -30,6 +30,9 @@
 #pragma GCC diagnostic ignored "-Wshadow"
 #pragma GCC diagnostic ignored "-Wunused-parameter"
 #pragma GCC diagnostic ignored "-Wsign-compare"
+#if defined(__clang__)
+#pragma clang diagnostic ignored "-Wheader-guard"
+#endif
 #endif
 #include "otb_shark.h"
 #include "shark/Data/Dataset.h"