diff --git a/CMake/cotire.cmake b/CMake/cotire.cmake
index 97275d6..a1c61c9 100644
--- a/CMake/cotire.cmake
+++ b/CMake/cotire.cmake
@@ -931,7 +931,8 @@ function (cotire_add_includes_to_cmd _cmdVar _language _includesVar _systemInclu
 					list (FIND ${_systemIncludesVar} "${_include}" _index)
 				endif()
 				if (_index GREATER -1)
-					list (APPEND ${_cmdVar} "${CMAKE_INCLUDE_SYSTEM_FLAG_${_language}}${CMAKE_INCLUDE_FLAG_SEP_${_language}}${_include}")
+					string (STRIP "${CMAKE_INCLUDE_SYSTEM_FLAG_${_language}}" _includeFlag)
+					list (APPEND ${_cmdVar} "${_includeFlag}${CMAKE_INCLUDE_FLAG_SEP_${_language}}${_include}")
 				else()
 					list (APPEND ${_cmdVar} "${CMAKE_INCLUDE_FLAG_${_language}}${CMAKE_INCLUDE_FLAG_SEP_${_language}}${_include}")
 				endif()