Re: [RFC] HOWTO find oops location

[Marcelo Tosatti <marcelo.tosatti@cyclades.com>]

On Sat, Aug 14, 2004 at 09:59:27PM +0300, Denis Vlasenko wrote:
> > > > Might be also worth mentioning "gcc -c file.c -g -Wa,-a,-ad  > file.s"
> > > > which makes gcc output C code mixed with asm output.
> > > >
> > > > Sometimes its not as effective as the comment method you describe,
> > > > but it will be less work for sure :)
> > >
> > > Aha! Cool.
> > >
> > > Mmmm... How to ensure that build environment exactly matches one
> > > used during make? Environment, -On level, regparm, other gcc switches,
> > > etc, etc, etc? Else file.s object code can be rather different from
> > > code in file.o...
> >
> > No idea.
> 
> I tried on 2.6:
> 
> make V=1 fs/dcache.o
> make V=1 CFLAGS="-g -Wa,-a,-ad" fs/dcache.o >dcache.asm
> 
> and compared gcc invocation commands. Pseudodiff:
> 
> - -Wall -Wstrict-prototypes -Wno-trigraphs -fno-strict-aliasing
> - -fno-common -pipe -msoft-float -mpreferred-stack-boundary=2
> - -march=i486 -I/.1/usr/srcdevel/kernel/linux-2.6.7-bk20.src/include/asm-i386/mach-default
> - -Iinclude/asm-i386/mach-default -O2 -falign-functions=1 -falign-labels=1 -falign-loops=1
> - -falign-jumps=1
> + -g -Wa,-a,-ad
> 
> :(

This worked for me:

gcc -c -g -Wa,-a,-ad -Wp,-MD,fs/.buffer.o.d -nostdinc -iwithprefix include -D__KERNEL__ -Iinclude  
-Wall -Wstrict-prototypes -Wno-trigraphs -fno-strict-aliasing -fno-common -pipe -msoft-float 
-mpreferred-stack-boundary=2  -march=athlon -Iinclude/asm-i386/mach-default -O2     
-DKBUILD_BASENAME=buffer -DKBUILD_MODNAME=buffer  fs/buffer.c

The order of the parameters matter in some way, which I have no idea of.