Re: finding unused header files

[Paul Bolle <pebolle@tiscali.nl>]

On Fri, 2012-06-22 at 06:46 -0400, Robert P. J. Day wrote:
> inspired by that last post that located an unused header file under
> arch/h8300, i ran my "find_unused_headers.sh" script on the same
> sub-directory to see what would show up.
> 
>   the script is stupidly conservative and didn't identify that shm.h
> header since *somewhere* in the entire kernel source tree, someone was
> including a file called "shm.h" -- not even for the same architecture.
> like i said, stupidly conservative.
> 
>   but it did find this:
> 
> $ ../s/find_unused_headers.sh arch/h8300
> ===== target_time.h =====
> ./arch/h8300/include/asm/target_time.h
> $
> 
> and i see nothing anywhere in the entire tree that includes a
> target_time.h header under any circumstances.

See my patch "h8300: delete
target_time.h" (https://lkml.org/lkml/2012/6/8/518 ). I don't remember
getting a reply to that message.

>   i should probably do another run of these scripts some day, just to
> see what turns up.

The script I use currently shows almost 200 (potentially) unused
headers. It's not very sophisticated and errs on the safe side (ie, it
must show absolutely no sign of files including the header). I'm not
sure whether a sophisticated approach is actually feasible.

In the last weeks I send patches to remove a few dozen of those 200
headers.


Paul Bolle