diff --git a/Point_set_processing_3/include/CGAL/IO/write_las_points.h b/Point_set_processing_3/include/CGAL/IO/write_las_points.h
index 661bdf86977..22e93b232b9 100644
--- a/Point_set_processing_3/include/CGAL/IO/write_las_points.h
+++ b/Point_set_processing_3/include/CGAL/IO/write_las_points.h
@@ -38,7 +38,7 @@
 #  pragma GCC diagnostic ignored "-Wstrict-aliasing"
 #endif
 
-#define USE_AS_DLL
+#define USE_AS_DLL 1
 #include <lasdefinitions.hpp>
 #include <lasreader_las.hpp>
 #include <laswriter_las.hpp>