diff --git a/source/CMakeLists.txt b/source/CMakeLists.txt
index 11e3593c..5c924e84 100644
--- a/source/CMakeLists.txt
+++ b/source/CMakeLists.txt
@@ -41,7 +41,7 @@ elseif(CMAKE_CXX_COMPILER_ID MATCHES "Clang")
   set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -Wno-padded") # ignore padding warnings
   set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -Wno-documentation-unknown-command") # ignore unknown commands in Javadoc-style comments
   set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -Wno-unknown-pragmas") # ignore Windows and GCC pragmas
-  set CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -Wno-unknown-warning-option") # ignore Windows and GCC pragmas
+  set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -Wno-unknown-warning-option") # ignore Windows and GCC pragmas
   set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -Wno-float-equal") # don't warn on uses of == for fp types
   set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -Wno-newline-eof") # no longer an issue with post-c++11 standards which mandate include add a newline if neccesary
   set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -Wno-covered-switch-default") # default is often added to switches for completeness or to cover future alternatives