diff --git a/cmake/genrev.cmake b/cmake/genrev.cmake
index 07f3b8d4d8..9f219a047a 100644
--- a/cmake/genrev.cmake
+++ b/cmake/genrev.cmake
@@ -134,7 +134,7 @@ if(WIN32)
 	OUTPUT_STRIP_TRAILING_WHITESPACE
   )
   # Remove "Microsoft Windows" from the result
-  string(REGEX REPLACE "^.* Windows " "" TRINITY_BUILD_HOST_SYSTEM_RELEASE ${TRINITY_BUILD_HOST_SYSTEM_RELEASE})
+  string(REGEX REPLACE "^.* Windows " "" TRINITY_BUILD_HOST_SYSTEM_RELEASE "${TRINITY_BUILD_HOST_SYSTEM_RELEASE}")
 endif()
 
 if(CMAKE_SCRIPT_MODE_FILE)