5.7.11.3 Idirafter Option

The -idirafter dir option adds the directory dir list of directories to be searched for header files during preprocessing. The directory is searched only after all other search paths (including the standard search directories as well as those specified by the -I and -Iquote options) have been searched. If this option is used more than once, the directories they specify are searched in a left-to-right order as they appear on the command line.