Add -N support to ELF?

[H.J. Lu]

> 
>    From: hjl@nynexst.com (H.J. Lu)
>    Date: Mon, 20 Feb 95 13:30:57 EST
> 
>    1. When -N is not used, if the sh_flags of the current section
>       is not compatible with the p_flags of the current segment, start
>       a new segment.
> 
>    2. When -N is used, behave just like the old way.
> 
> This seems reasonable in principle.  The trick is defining
> ``compatible'' is a useful fashion.  I have not been able to think of
> a good definition, but I haven't thought about it all that much,
> either.
> 
>    I can make the changes. But I don't think may changes will be
>    acceptable to everyone :-(. Will a new field in bfd_link_info help?
> 
> A new field is not necessary.  Check the flags field of the output
> field, and switch on the D_PAGED flag.  D_PAGED is set by default, and
> turned off when -N (or -n) is used.  For example, the a.out backend
> uses D_PAGED to determine whether the output file should be zmagic or
> omagic.
> 
> Ian
> 

This patch is derived from some patch I got, Eric? It should work
fine. Ian, is that ok to uncomment my patch to elf.sc with this one
applied? I guess the docs should be updated to reflect the usage
of -N in ELF.

Thanks.



-- 
H.J. Lu
NYNEX Science and Technology, Inc.			hjl@nynexst.com
-----
*** elfcode.h	Sat Feb 18 10:25:01 1995
--- elfcode.h.new	Mon Feb 20 16:13:22 1995
***************
*** 1968,1974 ****
--- 1968,1986 ----
        if (phdr->p_type != PT_NULL
  	  && (hdr->sh_offset - (phdr->p_offset + phdr->p_memsz)
  	      == hdr->sh_addr - (phdr->p_vaddr + phdr->p_memsz))
+ #if 1
+ 	  && (last_type != SHT_NOBITS || hdr->sh_type == SHT_NOBITS)
+ 	  /* We check to see if the binary is for demand page. We
+ 	     want to make sure the curent section is compatible with
+ 	     the current segment. Otherwise, start a new segment. We
+ 	     have to be very careful about elf.sc. Don't put any
+ 	     writable sections into the text segment. */
+ 	  && (((abfd->flags & D_PAGED) == 0)
+ 	      || (((hdr->sh_flags & SHF_WRITE) == 0 && (phdr->p_flags & PF_W) == 0)
+ 	      || ((hdr->sh_flags & SHF_WRITE) != 0 && (phdr->p_flags & PF_W) != 0))))
+ #else
  	  && (last_type != SHT_NOBITS || hdr->sh_type == SHT_NOBITS))
+ #endif
  	{
  	  bfd_size_type adjust;