diff --git a/Installation/CMakeLists.txt b/Installation/CMakeLists.txt
index 7f576591812..87887e6a70d 100644
--- a/Installation/CMakeLists.txt
+++ b/Installation/CMakeLists.txt
@@ -128,7 +128,7 @@ if ( CGAL_BRANCH_BUILD )
 
     MACRO(Subversion_GET_REVISION dir variable)
      # use svnversion
-     EXECUTE_PROCESS(COMMAND ${SVN_EXECUTABLE} info --xml ${dir}
+     EXECUTE_PROCESS(COMMAND "${SVN_EXECUTABLE}" info --xml "${dir}"
         OUTPUT_VARIABLE ${variable}
         OUTPUT_STRIP_TRAILING_WHITESPACE)
       STRING(REGEX REPLACE "^(.*\n)?   revision=\"([^\n]+)\".*url.*" "\\2" ${variable} "${${variable}}")
diff --git a/Installation/cmake/modules/CGAL_Macros.cmake b/Installation/cmake/modules/CGAL_Macros.cmake
index bdd3c48ec92..5d0a1e20445 100644
--- a/Installation/cmake/modules/CGAL_Macros.cmake
+++ b/Installation/cmake/modules/CGAL_Macros.cmake
@@ -109,14 +109,14 @@ if( NOT CGAL_MACROS_FILE_INCLUDED )
     message("Compiler version:")
     set(version "Unknown compiler. Cannot display its version")
     foreach(flag "-V" "--version" "-v")
-      execute_process(COMMAND ${CMAKE_CXX_COMPILER} ${flag}
+      execute_process(COMMAND "${CMAKE_CXX_COMPILER}" ${flag}
         RESULT_VARIABLE ok
         OUTPUT_VARIABLE out_version
         ERROR_VARIABLE out_version
         TIMEOUT 5)
       if(ok EQUAL 0)
         if("${out_version}" MATCHES "^clang")
-          execute_process(COMMAND ${CMAKE_CXX_COMPILER} -print-search-dirs
+          execute_process(COMMAND "${CMAKE_CXX_COMPILER}" -print-search-dirs
             RESULT_VARIABLE ok
             OUTPUT_VARIABLE out_search_dirs
             TIMEOUT 5)