--- a/CMakeLists.txt	2015-08-12 20:04:55.397881480 +0200
+++ b/CMakeLists.txt	2015-08-12 20:05:06.625741113 +0200
@@ -152,11 +152,6 @@
 
 string(TOUPPER "${CMAKE_BUILD_TYPE}" uppercase_CMAKE_BUILD_TYPE)
 
-if (CMAKE_BUILD_TYPE AND
-    NOT uppercase_CMAKE_BUILD_TYPE MATCHES "^(DEBUG|RELEASE|RELWITHDEBINFO|MINSIZEREL)$")
-  message(FATAL_ERROR "Invalid value for CMAKE_BUILD_TYPE: ${CMAKE_BUILD_TYPE}")
-endif()
-
 set(LLVM_LIBDIR_SUFFIX "" CACHE STRING "Define suffix of library directory name (32/64)" )
 
 # They are used as destination of target generators.