don't know how to do to help you in your project

Well, you've proposed doing something that is interesting (expanding kernel programming support to GNU as), but that was not in our todo list: I think that can be called helping us, can't it ?

I'm not an expert of "kernel" programming ( that's an understatement ), so I'll let PpHd, you and others should decide the exact extent of what should be in the "kernel.h" GNU as header (which functions and libraries are deprecated, which are not, etc.).
Definitions that are identical in "kernel.h" (both the C version and the GNU as version) and in other headers (TIGCCLIB C headers, GNU as os.h) mustn't be duplicated, duplication is only a source of problems.
I did de-duplication on the C kernel.h header, slashing its size by nearly 90%. I committed this morning my changes into the "kernelh-inclusion" branch of the repository ( you can find the individual files in http://trac.godzil.net/gcc4ti/ticket/9 ).