empty autoconf.h = module compile errors

James Iwanek chthon at chthon-uk.com
Sat Mar 1 05:13:03 PST 2003

Matt Bartley wrote:

> Now that I have a nicely operating LFS partition (built from the
> pure-lfs hint, followed by some goodies from BLFS), I've been
> experimenting with compiling device driver modules.
> My system is a 300 MHZ K6-2, now with glibc-2.3.1, gcc-3.2.2,
> and kernel 2.4.20.
> I'm following along with the O'Reily Linux Device Drivers book.
> (The bucking horse book.)
> I quickly found that even simple programs would bomb during compile:
> In file included from /usr/include/linux/prefetch.h:13,
>                            from /usr/include/linux/list.h:6,
>                            from /usr/include/linux/module.h:12,
>                            hellomod.c:8:
> /usr/include/asm/processor.h:56: `CONFIG_X86_L1_CACHE_SHIFT' undeclared
>   here (not in a function)
> /usr/include/asm/processor.h:56: requested alignment is not a constant
> After much tracing through the include files, I discovered the problem
> ,or at least *a* problem.
> The include files are looking at /usr/include/linux/autoconf.h for the
> definition of CONFIG_X86_L1_CACHE_SHIFT.  The LFS book, as well as the
> pure_lfs hint, mention creating an empty /usr/include/linux/autoconf.h
> file after installing the kernel headers.
> I  cd into /usr/src/linux and ran make oldconfig (I saved the .config
> file from my previous kernel compile), then copied the newly-created
> /usr/src/linux/include/linux/autoconf.h over to
> /usr/include/linux/autoconf.h
> Now /usr/include/linux/autoconf.h contains
> #define CONFIG_X86_L1_CACHE_SHIFT (5)
> Problem apparently solved.
> This may be an obscure case, but /usr/include/linux/autoconf.h ought to
> not be left blank after the LFS install.  What would be appropriate?
> Perhaps the include/linux/autoconf.h file resulting from compiling the
> kernel in Chapter 8 : Installing Linux 2.4.20?

which programs does this occur with?
Unsubscribe: send email to listar at linuxfromscratch.org
and put 'unsubscribe lfs-dev' in the subject header of the message

More information about the lfs-dev mailing list