Re: PATCH: PR ld/10569: -z max-page-size may not work for linker scripts

[Alan Modra <amodra@bigpond.net.au>]

On Fri, Aug 28, 2009 at 06:40:42AM -0700, H.J. Lu wrote:
> On Thu, Aug 27, 2009 at 10:50 PM, Alan Modra<amodra@bigpond.net.au> wrote:
> > On Thu, Aug 27, 2009 at 08:55:46PM -0700, H.J. Lu wrote:
> >> On Thu, Aug 27, 2009 at 8:32 PM, H.J. Lu<hjl.tools@gmail.com> wrote:
> >> > On Thu, Aug 27, 2009 at 8:14 PM, Alan Modra<amodra@bigpond.net.au> wrote:
> >> >> I think this is the wrong place to call bfd_emul_set_maxpagesize
> >> >> (and the current call in elf32.em is wrong too).  You probably should
> >> >> be calling bfd_emul_set_maxpagesize in open_output.  Also,
> >> >
> >> > Will open_output be called before any linker scripts are processed?
> >
> > Depends on what you mean by processed.  Yes, they are parsed and
> > converted to internal format before open_output, but why does it
> > matter?  Nothing much depends on maxpagesize until
> > lang_size_sections.
> 
> This linker script:
> 
> ---
> SECTIONS
> {
>   .text : {*(.text)}
>   . = ALIGN(CONSTANT (MAXPAGESIZE));
>   .data : {*(.data)}
>   /DISCARD/ : {*(*)}
> }
> ---
> 
> calls fold_name on MAXPAGESIZE before open_output is called.

You are allowed to fail in fold_name if output_target is not set.  See
many other examples where we return !result.valid_p if attempting to
evaluate early in the link.

> > Why can't you use output_target?
> >
> 
> We may set and get page sizes in linker. In linker script, we should use
> emulation target, which may be different from output target, to get
> page size, We need to set page size for emulation target in
> gld${EMULATION_NAME}_handle_option. We also need to set page
> size for output target in ldemul_set_output_arch.

If you accept a fail in fold_name, then I think your argument
collapses.  After output_target has been set, that's the right target
to use.

-- 
Alan Modra
Australia Development Lab, IBM