diff --git a/CMakeLists.txt b/CMakeLists.txt
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -14,6 +14,9 @@
 INCLUDE(FindDoxygen)
 INCLUDE(FindGhostscript)
 
+INCLUDE(CheckTypeSize)
+CHECK_TYPE_SIZE("long long" LONG_LONG)
+
 ENABLE_TESTING()
 
 ADD_SUBDIRECTORY(lemon)