Re: Kconfig no longer outputs a .config with freshly updated defconfigs

[Adrian Bunk <bunk@kernel.org>]

On Sat, Aug 02, 2008 at 12:03:33PM -0400, Josh Boyer wrote:
> I was going through the somewhat tedious task of updating the 4xx
> defconfigs today, and I noticed some odd behavior from Kconfig.
> Basically, I would do:
> 
> 	make ppc44x_defconfig
> 	make oldconfig
> 	<build>
> 	cp .config arch/powerpc/configs/ppc44x_defconfig
> 	make distclean
> 
> I did this for a number of configs.  Then I went back and tried to build
> ppc44x_defconfig again and I got this result:
> 
> [jwboyer@localhost linux-2.6]$ make ppc44x_defconfig
>   HOSTCC  scripts/basic/fixdep
>   HOSTCC  scripts/basic/docproc
>   HOSTCC  scripts/kconfig/conf.o
>   HOSTCC  scripts/kconfig/kxgettext.o
>   SHIPPED scripts/kconfig/zconf.tab.c
>   SHIPPED scripts/kconfig/lex.zconf.c
>   SHIPPED scripts/kconfig/zconf.hash.c
>   HOSTCC  scripts/kconfig/zconf.tab.o
> scripts/kconfig/lex.zconf.c:1628: warning: ‘input’ defined but not used
>   HOSTLD  scripts/kconfig/conf
> [jwboyer@localhost linux-2.6]$ make oldconfig
> scripts/kconfig/conf -o arch/powerpc/Kconfig
> #
> # using defaults found in /boot/config-2.6.25.13-104.fc9.ppc64
> #
> 
> There was no .config file present after the initial 'make
> ppc44x_defconfig', so it defaulted to using something in /boot.  I'm a
> bit baffled here, but that seems to be common to any newly updated
> defconfig I've done.
> 
> Was there a change to Kconfig recently that won't copy the defconfig
> file to .config if there are no symbol changes or something like that?

Thanks for your bug report, this should have worked.

@Sam:
I've bisected this and it is caused by
commit f443d2eccf077afd8a839cc7ed66cc4d520c5f05
(kconfig: speed up all*config + randconfig).

Minimal example for reproducing it:

make x86_64_defconfig
cp .config arch/x86/configs/x86_64_defconfig
rm .config
make x86_64_defconfig
ls .config

> josh

cu
Adrian

-- 

       "Is there not promise of rain?" Ling Tan asked suddenly out
        of the darkness. There had been need of rain for many days.
       "Only a promise," Lao Er said.
                                       Pearl S. Buck - Dragon Seed