Re: [PATCH] x86: linker script syntax nits

[Ingo Molnar <mingo@elte.hu>]

* Sam Ravnborg <sam@ravnborg.org> wrote:

> On Wed, Oct 14, 2009 at 03:10:24PM -0700, Roland McGrath wrote:
> > The following changes since commit 80f506918fdaaca6b574ba931536a58ce015c7be:
> >   Linus Torvalds (1):
> >         Merge branch 'for-linus' of git://git.kernel.dk/linux-2.6-block
> > 
> > are available in the git repository at:
> > 
> >   git://git.kernel.org/pub/scm/linux/kernel/git/frob/linux-2.6-roland.git topic/x86-lds-nits
> > 
> > Roland McGrath (1):
> >       x86: linker script syntax nits
> > 
> >  arch/x86/kernel/acpi/realmode/wakeup.lds.S |    4 ++--
> >  arch/x86/kernel/vmlinux.lds.S              |   17 ++++++++---------
> >  2 files changed, 10 insertions(+), 11 deletions(-)
> > ---
> > [PATCH] x86: linker script syntax nits
> > 
> > The linker scripts grew some use of weirdly wrong linker script syntax.
> > It happens to work, but it's not what the syntax is documented to be.
> > Clean it up to use the official syntax.
> > 
> > Signed-off-by: Roland McGrath <roland@redhat.com>
> > CC: Ian Lance Taylor <iant@google.com>
> > ---
> >  arch/x86/kernel/acpi/realmode/wakeup.lds.S |    4 ++--
> >  arch/x86/kernel/vmlinux.lds.S              |   17 ++++++++---------
> >  2 files changed, 10 insertions(+), 11 deletions(-)
> > 
> > diff --git a/arch/x86/kernel/acpi/realmode/wakeup.lds.S b/arch/x86/kernel/acpi/realmode/wakeup.lds.S
> > index 7da00b7..0e50e1e 100644
> > --- a/arch/x86/kernel/acpi/realmode/wakeup.lds.S
> > +++ b/arch/x86/kernel/acpi/realmode/wakeup.lds.S
> > @@ -56,6 +56,6 @@ SECTIONS
> >  	/DISCARD/ : {
> >  		*(.note*)
> >  	}
> > -
> > -	. = ASSERT(_end <= WAKEUP_SIZE, "Wakeup too big!");
> >  }
> > +
> > +ASSERT(_end <= WAKEUP_SIZE, "Wakeup too big!");
> 
> This breaks with older binutils. See 
> d2ba8b211bb8abc29aa627dbd4dce08cfbc8082b for reference.
> 
> Same goes for the other cahnges in this post.
> 
> Yup - it looks ugly :-(

We could introduce a COMPAT_ASSERT() wrapper perhaps, to move it more in 
line with the 'official' syntax.

Or we could wrap ASSERT() itself (this runs through the preprocessor 
before going to the linker) - although that would be a pretty obfuscated 
move.

At minimum we should add a comment to the first use of ASSERT() here 
that we assign the current address due to compatibility reasons. (same 
goes for arch/x86/boot/setup.ld)

Anyway - any such cleanup would be .33 material.

	Ingo