diff --git a/CMakeLists.txt b/CMakeLists.txt
index a26b240..00a7a4f 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -66,6 +66,8 @@ else()
     OUTPUT_STRIP_TRAILING_WHITESPACE)
   if (${RET} EQUAL 0)
     add_definitions(-DOWLPS_VERSION="${OWLPS_VERSION}")
+  else()
+    add_definitions(-DOWLPS_VERSION="unknown version")
   endif()
 endif()