2002-08-22 16:37:19

by Chris Friesen

[permalink] [raw]
Subject: is kernel compilation supposed to change header file timestamps?


I noticed the other day that on a kernel compile, the timestamps of some files are changed. The
funny thing is that all the changed ones are header files, but not all header files are modified.

Is this expected behaviour?

Chris

--
Chris Friesen | MailStop: 043/33/F10
Nortel Networks | work: (613) 765-0557
3500 Carling Avenue | fax: (613) 765-2986
Nepean, ON K2H 8E9 Canada | email: [email protected]


2002-08-22 17:03:23

by George Anzinger

[permalink] [raw]
Subject: Re: is kernel compilation supposed to change header file timestamps?

Chris Friesen wrote:
>
> I noticed the other day that on a kernel compile, the timestamps of some files are changed. The
> funny thing is that all the changed ones are header files, but not all header files are modified.
>
> Is this expected behaviour?
>
Yes, it has to do with how dependencies are propagated from
header file to header file (i.e. where a header file
includes another). Or, at least, I think this is what is
going on.
--
George Anzinger [email protected]
High-res-timers:
http://sourceforge.net/projects/high-res-timers/
Preemption patch:
http://www.kernel.org/pub/linux/kernel/people/rml

2002-08-22 17:19:00

by Sam Ravnborg

[permalink] [raw]
Subject: Re: is kernel compilation supposed to change header file timestamps?

On Thu, Aug 22, 2002 at 12:41:19PM -0400, Chris Friesen wrote:
>
> I noticed the other day that on a kernel compile, the timestamps of some files are changed. The
> funny thing is that all the changed ones are header files, but not all header files are modified.
>
> Is this expected behaviour?
I assume you are compiling a 2.4 kernel, in which case this is expected
behaviour.
For the 2.5 kernel kbuild has been changed such that
header files are no longer 'touched' during the compile process.

Sam