default include files only included in main file ?

[Prathamesh Kulkarni]

Hi, sorry to ask a daft question, but are default include files (eg:
stdc-predef.h) only included in the main file ?

So can I safely assume that if a particular file's include type is
IT_DEFAULT or IT_CMDLINE (passed by -include), then the file
#including it, shall be the main file (ie _cpp_file->main_file shall
be true for that file) ?

Thanks and Regards,
Prathamesh