add or move include guards

Number_types/include/CGAL/Exact_rational.h

@@ -14,6 +14,9 @@
 //
 // Author(s)     : Laurent Rineau
 
+#ifndef CGAL_EXACT_RATIONAL_H
+#define CGAL_EXACT_RATIONAL_H
+
 #include <CGAL/Number_types/internal/Exact_type_selector.h>
 
 namespace CGAL {
@@ -44,3 +47,5 @@ typedef internal::Exact_field_selector<double>::Type Exact_rational;
 #endif
 
 } /* end namespace CGAL */
+
+#endif // CGAL_EXACT_RATIONAL_H

Number_types/include/CGAL/Mpzf.h

@@ -10,12 +10,13 @@
 //
 // Author(s)        :  Marc Glisse
 
+#ifndef CGAL_MPZF_H
+#define CGAL_MPZF_H
+
 #ifndef CGAL_NO_MPZF_DIVISION_OPERATOR
 #define CGAL_MPZF_DIVISION_OPERATOR 1
 #endif
 
-#ifndef CGAL_MPZF_H
-#define CGAL_MPZF_H
 #include <cstdlib>
 #include <algorithm>
 #include <climits>

STL_Extension/include/CGAL/assertions_behaviour.h

@@ -14,11 +14,11 @@
 //
 // Author(s)     : Geert-Jan Giezeman and Sven Schoenherr
 
-#include <CGAL/config.h>
-
 #ifndef CGAL_ASSERTIONS_BEHAVIOUR_H
 #define CGAL_ASSERTIONS_BEHAVIOUR_H
 
+#include <CGAL/config.h>
+
 // workaround against the definition of EXIT in <opencv2/core/internal.hpp>
 #ifdef EXIT
 #  undef EXIT