diff --git a/Polygonal_surface_reconstruction/examples/Polygonal_surface_reconstruction/CMakeLists.txt b/Polygonal_surface_reconstruction/examples/Polygonal_surface_reconstruction/CMakeLists.txt
index b03959441ab..f2805ea6ec7 100644
--- a/Polygonal_surface_reconstruction/examples/Polygonal_surface_reconstruction/CMakeLists.txt
+++ b/Polygonal_surface_reconstruction/examples/Polygonal_surface_reconstruction/CMakeLists.txt
@@ -4,14 +4,14 @@
 project( Polygonal_surface_reconstruction_Examples )
 
 
-cmake_minimum_required(VERSION 2.8.11)
+cmake_minimum_required(VERSION 3.1...3.15)
 
 # CGAL and its components
 find_package( CGAL QUIET COMPONENTS  )
 
 if ( NOT CGAL_FOUND )
 
-  message(STATUS "This project requires the CGAL library, and will not be compiled.")
+  message(STATUS "NOTICE: This project requires the CGAL library, and will not be compiled.")
   return()  
 
 endif()
@@ -25,7 +25,7 @@ find_package( Boost REQUIRED )
 
 if ( NOT Boost_FOUND )
 
-  message(STATUS "This project requires the Boost library, and will not be compiled.")
+  message(STATUS "NOTICE: This project requires the Boost library, and will not be compiled.")
 
   return()  
 
@@ -49,10 +49,10 @@ if ( NOT SCIP_FOUND )
     find_package( GLPK )
 
     if ( NOT GLPK_FOUND )
-      message(STATUS "This project requires either SCIP or GLPK, and will not be compiled. "
+      message(STATUS "NOTICE: This project requires either SCIP or GLPK, and will not be compiled. "
                       "Please proivde either 'SCIP_DIR' or 'GLPK_INCLUDE_DIR' and 'GLPK_LIBRARIES'")
     else()
-        add_compile_definitions(CGAL_USE_GLPK)
+        add_definitions(-DCGAL_USE_GLPK)
 
         include_directories( BEFORE ${GLPK_INCLUDE_DIR} )
 
@@ -66,7 +66,7 @@ if ( NOT SCIP_FOUND )
 
 else()
 
-    add_compile_definitions(CGAL_USE_SCIP)
+    add_definitions(-DCGAL_USE_SCIP)
 
     include_directories( BEFORE ${SCIP_INCLUDE_DIRS} )
 
diff --git a/Polygonal_surface_reconstruction/examples/Polygonal_surface_reconstruction/polyfit_example_model_complexty_control.cpp b/Polygonal_surface_reconstruction/examples/Polygonal_surface_reconstruction/polyfit_example_model_complexty_control.cpp
index 5ff14cbc0fd..44d0ab7d916 100644
--- a/Polygonal_surface_reconstruction/examples/Polygonal_surface_reconstruction/polyfit_example_model_complexty_control.cpp
+++ b/Polygonal_surface_reconstruction/examples/Polygonal_surface_reconstruction/polyfit_example_model_complexty_control.cpp
@@ -147,7 +147,7 @@ int main()
 int main(int argc, char* argv[])
 {
     std::cerr << "This test requires either GLPK or SCIP.\n";
-    return EXIT_FAILURE;
+    return EXIT_SUCCESS;
 }
 
 #endif  // defined(CGAL_USE_GLPK) || defined(CGAL_USE_SCIP)
diff --git a/Polygonal_surface_reconstruction/examples/Polygonal_surface_reconstruction/polyfit_example_user_provided_planes.cpp b/Polygonal_surface_reconstruction/examples/Polygonal_surface_reconstruction/polyfit_example_user_provided_planes.cpp
index b6d801bed7d..8e8daded4d9 100644
--- a/Polygonal_surface_reconstruction/examples/Polygonal_surface_reconstruction/polyfit_example_user_provided_planes.cpp
+++ b/Polygonal_surface_reconstruction/examples/Polygonal_surface_reconstruction/polyfit_example_user_provided_planes.cpp
@@ -110,7 +110,7 @@ int main()
 int main(int argc, char* argv[])
 {
     std::cerr << "This test requires either GLPK or SCIP.\n";
-    return EXIT_FAILURE;
+    return EXIT_SUCCESS;
 }
 
 #endif  // defined(CGAL_USE_GLPK) || defined(CGAL_USE_SCIP)
diff --git a/Polygonal_surface_reconstruction/examples/Polygonal_surface_reconstruction/polyfit_example_without_input_planes.cpp b/Polygonal_surface_reconstruction/examples/Polygonal_surface_reconstruction/polyfit_example_without_input_planes.cpp
index e00bc6cf861..2580d606dca 100644
--- a/Polygonal_surface_reconstruction/examples/Polygonal_surface_reconstruction/polyfit_example_without_input_planes.cpp
+++ b/Polygonal_surface_reconstruction/examples/Polygonal_surface_reconstruction/polyfit_example_without_input_planes.cpp
@@ -155,7 +155,7 @@ int main()
 int main(int argc, char* argv[])
 {
     std::cerr << "This test requires either GLPK or SCIP.\n";
-    return EXIT_FAILURE;
+    return EXIT_SUCCESS;
 }
 
 #endif  // defined(CGAL_USE_GLPK) || defined(CGAL_USE_SCIP)
diff --git a/Polygonal_surface_reconstruction/test/Polygonal_surface_reconstruction/CMakeLists.txt b/Polygonal_surface_reconstruction/test/Polygonal_surface_reconstruction/CMakeLists.txt
index 8c4d1514c58..1e167802944 100644
--- a/Polygonal_surface_reconstruction/test/Polygonal_surface_reconstruction/CMakeLists.txt
+++ b/Polygonal_surface_reconstruction/test/Polygonal_surface_reconstruction/CMakeLists.txt
@@ -4,7 +4,7 @@
 project( Polygonal_surface_reconstruction_Tests )
 
 
-cmake_minimum_required(VERSION 2.8.11)
+cmake_minimum_required(VERSION 3.1...3.15)
 
 # CGAL and its components
 find_package( CGAL QUIET COMPONENTS  )
@@ -53,7 +53,7 @@ if (SCIP_FOUND)
 
   target_link_libraries( polygonal_surface_reconstruction_test PRIVATE ${SCIP_LIBRARIES} )
 
-  add_compile_definitions(CGAL_USE_SCIP)
+  add_definitions(-DCGAL_USE_SCIP)
 
   message("SCIP found and used")
 
@@ -68,7 +68,7 @@ find_package( GLPK )
 
       target_link_libraries( polygonal_surface_reconstruction_test PRIVATE ${GLPK_LIBRARIES} )
 
-      add_compile_definitions(CGAL_USE_GLPK)
+      add_definitions(-DCGAL_USE_GLPK)
 
       message("GLPK found and used")
 
diff --git a/Polygonal_surface_reconstruction/test/Polygonal_surface_reconstruction/polygonal_surface_reconstruction_test.cpp b/Polygonal_surface_reconstruction/test/Polygonal_surface_reconstruction/polygonal_surface_reconstruction_test.cpp
index 1f32470fcbf..19c209821bb 100644
--- a/Polygonal_surface_reconstruction/test/Polygonal_surface_reconstruction/polygonal_surface_reconstruction_test.cpp
+++ b/Polygonal_surface_reconstruction/test/Polygonal_surface_reconstruction/polygonal_surface_reconstruction_test.cpp
@@ -43,7 +43,6 @@ int main(int argc, char* argv[])
     //argv[1] = "data/house.ply";
     //argv[1] = "data/chair.ply";
     //argv[1] = "data/square.ply";
-#endif
 
 	// usage
 	if (argc - 1 == 0) {
@@ -53,8 +52,11 @@ int main(int argc, char* argv[])
         std::cerr << "Input file formats are \'pwn\' and \'ply\'. No output.\n";
 		return EXIT_FAILURE;
 	}
+#endif
 
-	char* input_file = argv[1];
+        const char* input_file =
+            (argc > 1) ? argv[1]
+            : "data/icosahedron.pwn";
 
 	//---------------------------------------------------------------------
 
@@ -116,7 +118,7 @@ int main(int argc, char* argv[])
 int main(int argc, char* argv[])
 {
     std::cerr << "This test requires either GLPK or SCIP.\n";
-    return EXIT_FAILURE;
+    return EXIT_SUCCESS;
 }
 
 #endif  // defined(CGAL_USE_GLPK) || defined(CGAL_USE_SCIP)
diff --git a/Solver_interface/examples/Solver_interface/CMakeLists.txt b/Solver_interface/examples/Solver_interface/CMakeLists.txt
index 7b488ac7a14..bd39ba190d7 100644
--- a/Solver_interface/examples/Solver_interface/CMakeLists.txt
+++ b/Solver_interface/examples/Solver_interface/CMakeLists.txt
@@ -4,7 +4,7 @@
 
 project( Solver_interface_Examples )
 
-cmake_minimum_required(VERSION 3.1)
+cmake_minimum_required(VERSION 3.1...3.15)
 
 find_package(CGAL QUIET)
 
@@ -30,7 +30,7 @@ if ( CGAL_FOUND )
 
     target_link_libraries( mixed_integer_program PRIVATE ${SCIP_LIBRARIES} )
 
-    add_compile_definitions(CGAL_USE_SCIP)
+    add_definitions(-DCGAL_USE_SCIP)
 
     message("SCIP found and used")
 
@@ -44,13 +44,13 @@ if ( CGAL_FOUND )
 
         target_link_libraries( mixed_integer_program PRIVATE ${GLPK_LIBRARIES} )
 
-        add_compile_definitions(CGAL_USE_GLPK)
+        add_definitions(-DCGAL_USE_GLPK)
 
         message("GLPK found and used")
 
       else()
 
-        message(STATUS "This project requires either SCIP or GLPK, and will not be compiled. "
+        message(STATUS "NOTICE: This project requires either SCIP or GLPK, and will not be compiled. "
             "Please proivde either 'SCIP_DIR' or 'GLPK_INCLUDE_DIR' and 'GLPK_LIBRARIES'")
 
       endif()
@@ -59,7 +59,7 @@ if ( CGAL_FOUND )
 
 else()
   
-    message(STATUS "This program requires the CGAL library, and will not be compiled.")
+    message(STATUS "NOTICE: This program requires the CGAL library, and will not be compiled.")
   
 endif()
 
diff --git a/Solver_interface/examples/Solver_interface/mixed_integer_program.cpp b/Solver_interface/examples/Solver_interface/mixed_integer_program.cpp
index 4368628cd51..4102e8f999f 100644
--- a/Solver_interface/examples/Solver_interface/mixed_integer_program.cpp
+++ b/Solver_interface/examples/Solver_interface/mixed_integer_program.cpp
@@ -106,7 +106,7 @@ int main()
 int main(int argc, char* argv[])
 {
     std::cerr << "This test requires either GLPK or SCIP.\n";
-    return EXIT_FAILURE;
+    return EXIT_SUCCESS;
 }
 
 #endif  // defined(CGAL_USE_GLPK) || defined(CGAL_USE_SCIP)