Re: PATCH: Map GNU attributes section to PT_GNU_ATTR (aka PT_GNU_STACK) segment

[Daniel Jacobowitz <drow at false dot org>]

On Thu, Aug 16, 2007 at 06:53:58AM -0700, H.J. Lu wrote:
> On Thu, Aug 16, 2007 at 09:43:10AM -0400, Daniel Jacobowitz wrote:
> > I don't think this patch is a good idea.  I would prefer to back it
> > out until there is a clear use case and support from at least one
> > consumer.
> 
> I have got a request to mark a binary for a totally different ABI than
> the normal one. They wanted to use ELF header to mark the ABI. But the
> bits in ELF header are very limited. The attribute section is
> perfect for this.

I stand by my request.  Please at least talk to Jakub about this
before you go changing program headers.

> > > Assuming we want to make the attribute section SHF_ALLOC, what kind
> > > of problem will it cause for ARM EABI?
> > 
> > Apparently none; the EABI does not specify that the section is
> > non-ALLOC.
> > 
> 
> Then, can we make the attribute section SHF_ALLOC?

We may need a separate section for runtime useful notes.  I have not
thought about it, but someone needs to.  The attributes section can
get pretty bulky, e.g. 57 bytes for the default options of the ARM
compiler on an empty file.  We've been discussing internally an
attribute that would take a pathname, too.

-- 
Daniel Jacobowitz
CodeSourcery