diff --git a/CMakeLists.txt b/CMakeLists.txt
index 757a416..24a8e6c 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -41,8 +41,8 @@ endif()
 option(USE_PI_MUTEX "Enables priority inheritance mutexes." ON)
 if(USE_PI_MUTEX)
   if(CMAKE_SYSTEM_NAME STREQUAL Linux OR
-     CMAKE_SYSTEM_NAME STREQUAL VxWorks OR
-     CMAKE_SYSTEM_NAME STREQUAL QNX)
+    CMAKE_SYSTEM_NAME STREQUAL VxWorks OR
+    CMAKE_SYSTEM_NAME STREQUAL QNX)
     target_compile_definitions(${PROJECT_NAME} PUBLIC "RCPPUTILS_USE_PIMUTEX")
   else()
     message("Mutexes with priority inheritance are not supported on your system. Using std mutexes.")