use CMAKE_INCLUDE_FLAG_C and CMAKE_INCLUDE_FLAG_CXX

CMake/cotire.cmake

@@ -678,8 +678,23 @@ function (cotire_get_target_compiler_flags _config _language _target _compilerFl
 	# parse target compile flags omitting compile definitions and include directives
 	set (_targetFlags "")
 	cotire_get_target_compile_flags("${_config}" "${_language}" "${_target}" _targetFlags)
+	set (_flagFilter "D")
+	if (CMAKE_INCLUDE_FLAG_${_language})
+		string (STRIP "${CMAKE_INCLUDE_FLAG_${_language}}" _includeFlag)
+		string (REGEX REPLACE "^[-/]+" "" _includeFlag "${_includeFlag}")
+		if (_includeFlag)
+			set (_flagFilter "${_flagFilter}|${_includeFlag}")
+		endif()
+	endif()
+	if (CMAKE_INCLUDE_SYSTEM_FLAG_${_language})
+		string (STRIP "${CMAKE_INCLUDE_SYSTEM_FLAG_${_language}}" _includeFlag)
+		string (REGEX REPLACE "^[-/]+" "" _includeFlag "${_includeFlag}")
+		if (_includeFlag)
+			set (_flagFilter "${_flagFilter}|${_includeFlag}")
+		endif()
+	endif()
 	set (_compilerFlags "")
-	cotire_filter_compile_flags("${_language}" "[ID]" _ignore _compilerFlags ${_targetFlags})
+	cotire_filter_compile_flags("${_language}" "${_flagFilter}" _ignore _compilerFlags ${_targetFlags})
 	if (COTIRE_DEBUG AND _compilerFlags)
 		message (STATUS "Target ${_target} compiler flags: ${_compilerFlags}")
 	endif()