Blackfin: fix crash when linking incompatible objects

[Bernd Schmidt <bernds_cb1 at t-online dot de>]

I'm a little behind applying patches from our local svn tree to the main
binutils tree.  Here's the first though, which fixes a crash when
linking incompatible object files (normal vs. FD-PIC), and also cleans
up and fixes the code that detects these mismatches and warns about them.

Committed.


Bernd
-- 
This footer brought to you by insane German lawmakers.
Analog Devices GmbH      Wilhelm-Wagenfeld-Str. 6      80807 Muenchen
Sitz der Gesellschaft Muenchen, Registergericht Muenchen HRB 40368
Geschaeftsfuehrer Thomas Wessel, William A. Martin, Margaret Seif

Index: bfd/ChangeLog
===================================================================
RCS file: /cvs/src/src/bfd/ChangeLog,v
retrieving revision 1.4128
diff -c -p -r1.4128 ChangeLog
*** bfd/ChangeLog	11 Feb 2008 13:52:01 -0000	1.4128
--- bfd/ChangeLog	11 Feb 2008 16:03:14 -0000
***************
*** 1,3 ****
--- 1,10 ----
+ 2008-02-11  Bernd Schmidt  <bernd.schmidt@analog.com>
+ 
+ 	* elf32-bfin.c (bfin_relocate_section): Set up dynobj before using it
+ 	if necessary.
+ 	(elf32_bfin_merge_private_bfd_data): Simplify, and ensure object type
+ 	mismatches are detected.
+ 
  2008-02-11  Daniel Jacobowitz  <dan@codesourcery.com>
  
  	* cache.c (cache_bread): Set bfd_error_file_truncated if EOF
Index: bfd/elf32-bfin.c
===================================================================
RCS file: /cvs/src/src/bfd/elf32-bfin.c,v
retrieving revision 1.26
diff -c -p -r1.26 elf32-bfin.c
*** bfd/elf32-bfin.c	31 Dec 2007 11:01:54 -0000	1.26
--- bfd/elf32-bfin.c	11 Feb 2008 16:03:15 -0000
*************** bfin_relocate_section (bfd * output_bfd,
*** 2924,2929 ****
--- 2924,2937 ----
  	  {
  	    bfd_vma off;
  
+ 	  if (dynobj == NULL)
+ 	    {
+ 	      /* Create the .got section.  */
+ 	      elf_hash_table (info)->dynobj = dynobj = output_bfd;
+ 	      if (!_bfd_elf_create_got_section (dynobj, info))
+ 		return FALSE;
+ 	    }
+ 
  	    if (sgot == NULL)
  	      {
  		sgot = bfd_get_section_by_name (dynobj, ".got");
*************** elf32_bfin_print_private_bfd_data (bfd *
*** 4795,4802 ****
  static bfd_boolean
  elf32_bfin_merge_private_bfd_data (bfd *ibfd, bfd *obfd)
  {
!   flagword old_flags, old_partial;
!   flagword new_flags, new_partial;
    bfd_boolean error = FALSE;
  
    new_flags = elf_elfheader (ibfd)->e_flags;
--- 4803,4809 ----
  static bfd_boolean
  elf32_bfin_merge_private_bfd_data (bfd *ibfd, bfd *obfd)
  {
!   flagword old_flags, new_flags;
    bfd_boolean error = FALSE;
  
    new_flags = elf_elfheader (ibfd)->e_flags;
*************** elf32_bfin_merge_private_bfd_data (bfd *
*** 4814,4850 ****
    if (!elf_flags_init (obfd))			/* First call, no flags set.  */
      {
        elf_flags_init (obfd) = TRUE;
!       old_flags = new_flags;
      }
  
!   else if (new_flags == old_flags)		/* Compatible flags are ok.  */
!     ;
! 
!   else						/* Possibly incompatible flags.  */
!     {
!       /* We don't have to do anything if the pic flags are the same, or the new
!          module(s) were compiled with -mlibrary-pic.  */
!       new_partial = (new_flags & EF_BFIN_PIC_FLAGS);
!       old_partial = (old_flags & EF_BFIN_PIC_FLAGS);
!       if (new_partial == old_partial)
! 	;
! 
!       /* If we have mixtures of -fpic and -fPIC, or in both bits.  */
!       else if (new_partial != 0 && old_partial != 0)
! 	old_flags |= new_partial;
! 
!       /* One module was compiled for pic and the other was not, see if we have
!          had any relocations that are not pic-safe.  */
!       else
! 	old_flags |= new_partial;
! 
!     }
! 
!   /* Update the old flags now with changes made above.  */
!   elf_elfheader (obfd)->e_flags = old_flags;
! 
!   if (((new_flags & EF_BFIN_FDPIC) == 0)
!       != (! IS_FDPIC (ibfd)))
      {
        error = TRUE;
        if (IS_FDPIC (obfd))
--- 4821,4830 ----
    if (!elf_flags_init (obfd))			/* First call, no flags set.  */
      {
        elf_flags_init (obfd) = TRUE;
!       elf_elfheader (obfd)->e_flags = new_flags;
      }
  
!   if (((new_flags & EF_BFIN_FDPIC) == 0) != (! IS_FDPIC (obfd)))
      {
        error = TRUE;
        if (IS_FDPIC (obfd))