diff --git a/CMakeLists.txt b/CMakeLists.txt
index 2c144601b7a..5a06011246f 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -717,7 +717,7 @@ if(UNIX AND NOT APPLE)
 
 	if(WITH_LLVM)
 		set(LLVM_DIRECTORY ${LIBDIR}/llvm CACHE PATH	"Path to the LLVM installation")
-		set(LLVM_VERSION "3.0" CACHE STRING	"Version of LLVM to use" "")
+		set(LLVM_VERSION "3.0" CACHE STRING	"Version of LLVM to use")
 		set(LLVM_STATIC YES)
 		if(LLVM_DIRECTORY)
 			set(LLVM_CONFIG "${LLVM_DIRECTORY}/bin/llvm-config")
@@ -1610,7 +1610,7 @@ elseif(APPLE)
 
 	if(WITH_LLVM)
 		set(LLVM_DIRECTORY ${LIBDIR}/llvm CACHE PATH	"Path to the LLVM installation")
-		set(LLVM_VERSION "3.1" CACHE STRING	"Version of LLVM to use" "")
+		set(LLVM_VERSION "3.1" CACHE STRING	"Version of LLVM to use")
 		set(LLVM_STATIC YES)
 		if(LLVM_DIRECTORY)
 			set(LLVM_CONFIG "${LLVM_DIRECTORY}/bin/llvm-config")