.bss section marked as contents, load, alloc, data

.bss section marked as contents, load, alloc, data

[Nick Kelsey]

Hi guys,

I am having a problem whereby all our elf files have the .bss section marked
as loadable:

10 .bss          000016a4  0010158c  0010158c  0000258c  2**4
                 CONTENTS, ALLOC, LOAD, DATA

I ran objdump -h on all .o files being linked and all show:

  2 .bss          00000000  00000000  00000000  00000034  2**0
                  ALLOC

Which looks correct.

Something must be making the linker think that it is loadable... but I have
no idea what.

Any advice as to how to trace the problem would be appreciated.

Thanks

Nick

Re: .bss section marked as contents, load, alloc, data

[Daniel Jacobowitz]

On Tue, Apr 06, 2004 at 02:21:42PM -0700, Nick Kelsey wrote:
> Hi guys,
> 
> I am having a problem whereby all our elf files have the .bss section marked
> as loadable:
> 
> 10 .bss          000016a4  0010158c  0010158c  0000258c  2**4
>                  CONTENTS, ALLOC, LOAD, DATA
> 
> I ran objdump -h on all .o files being linked and all show:
> 
>   2 .bss          00000000  00000000  00000000  00000034  2**0
>                   ALLOC
> 
> Which looks correct.
> 
> Something must be making the linker think that it is loadable... but I have
> no idea what.
> 
> Any advice as to how to trace the problem would be appreciated.

Are you sure you checked every library, archive, or system startup file
being linked?  I had a bad .sbss in crt0.o recently...

-- 
Daniel Jacobowitz
MontaVista Software                         Debian GNU/Linux Developer

Re: .bss section marked as contents, load, alloc, data

[Nick Kelsey]

Ok... found the problem...

Added a printf to _bfd_elf_make_section_from_shdr and it was setting the
SEC_LOAD flag because some assembler code was not using @nobits.

Because it was the linker appling the flag it does not show up as a flag in
the .o file.

My main concern now is someone forgetting @nobits and causing the same
problem again.

It is working now... thanks for the advice.

Nick

----- Original Message ----- 
From: "Jafa" <jafa@silicondust.com>
To: <binutils@sources.redhat.com>
Sent: Tuesday, April 06, 2004 2:57 PM
Subject: Re: .bss section marked as contents, load, alloc, data


> Yep... checked libgcc.a, libgdb.a, and every .o file in the application...
> all report ALLOC.
>
> I guess I will have to run gdb on the linker :-(
>
> Nick
>
> On Tue, Apr 06, 2004 at 02:21:42PM -0700, Nick Kelsey wrote:
> > Hi guys,
> >
> > I am having a problem whereby all our elf files have the .bss section
> marked
> > as loadable:
> >
> > 10 .bss          000016a4  0010158c  0010158c  0000258c  2**4
> >                  CONTENTS, ALLOC, LOAD, DATA
> >
> > I ran objdump -h on all .o files being linked and all show:
> >
> >   2 .bss          00000000  00000000  00000000  00000034  2**0
> >                   ALLOC
> >
> > Which looks correct.
> >
> > Something must be making the linker think that it is loadable... but I
> have
> > no idea what.
> >
> > Any advice as to how to trace the problem would be appreciated.
>
> Are you sure you checked every library, archive, or system startup file
> being linked?  I had a bad .sbss in crt0.o recently...
>
> -- 
> Daniel Jacobowitz
> MontaVista Software                         Debian GNU/Linux Developer
>

Re: .bss section marked as contents, load, alloc, data

[Ben Elliston]

"Jafa" <jafa@silicondust.com> writes:

> I guess I will have to run gdb on the linker :-(

My first port of call would be the linker script, especially if you
aren't using the default linker script.

Ben

Re: .bss section marked as contents, load, alloc, data

[Jafa]

Yep... checked libgcc.a, libgdb.a, and every .o file in the application...
all report ALLOC.

I guess I will have to run gdb on the linker :-(

Nick

On Tue, Apr 06, 2004 at 02:21:42PM -0700, Nick Kelsey wrote:
> Hi guys,
>
> I am having a problem whereby all our elf files have the .bss section
marked
> as loadable:
>
> 10 .bss          000016a4  0010158c  0010158c  0000258c  2**4
>                  CONTENTS, ALLOC, LOAD, DATA
>
> I ran objdump -h on all .o files being linked and all show:
>
>   2 .bss          00000000  00000000  00000000  00000034  2**0
>                   ALLOC
>
> Which looks correct.
>
> Something must be making the linker think that it is loadable... but I
have
> no idea what.
>
> Any advice as to how to trace the problem would be appreciated.

Are you sure you checked every library, archive, or system startup file
being linked?  I had a bad .sbss in crt0.o recently...

-- 
Daniel Jacobowitz
MontaVista Software                         Debian GNU/Linux Developer