diff --git a/CMakeLists.txt b/CMakeLists.txt
index 81c98a0..e4ca76c 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -20,13 +20,6 @@
   set(CMAKE_BUILD_TYPE "Release")
 endif()
 
-string(TOLOWER "${CMAKE_BUILD_TYPE}" cmake_build_type_tolower)
-if(    NOT cmake_build_type_tolower STREQUAL "debug"
-   AND NOT cmake_build_type_tolower STREQUAL "release"
-   AND NOT cmake_build_type_tolower STREQUAL "relwithdebinfo")
-  message(FATAL_ERROR "Unknown build type \"${CMAKE_BUILD_TYPE}\". Allowed values are Debug, Release, RelWithDebInfo (case-insensitive).")
-endif()
-
 
 #############################################################################
 # retrieve version information                                               #