Fix LTO vs. COFF archives

Avoid scan of symbols on objects in coff archives since we don't need
to do anything special with common symbols.  The scan is quite useless,
and breaks LTO due to slim LTO objects not having symbols available
until after the plugin has claimed them.  Instead we can add objects
based on their archive symbol map.

Also, rip out the archive symbol hash table used by the generic
linker.  Using a hash breaks one feature of unix archive linking;
The first object file in an archive defining any given symbol should
be the object extracted to satisfy that symbol.  What's more a hash
isn't much faster except in pathological cases where object file
ordering causes many scans of the archive.  See the comment which I'm
removing from elf_link_add_archive_symbols.

Finally, tidy elflink.c archive handling a little.

	PR 13557
	* linker.c (struct archive_list, struct archive_hash_entry,
	struct archive_hash_table, archive_hash_newfunc,
	archive_hash_table_init, archive_hash_lookup, archive_hash_allocate,
	archive_hash_table_free): Delete.
	(_bfd_generic_link_add_archive_symbols): Add h and name params to
	checkfn.  Rewrite using a straight-forward scan over archive map.
	(generic_link_check_archive_element_no_collect,
	generic_link_check_archive_element_collect,
	generic_link_check_archive_element): Add h and name params.
	* aoutx.h (aout_link_check_archive_element): Likewise.
	* pdp11.c (aout_link_check_archive_element): Likewise.
	* xcofflink.c (xcoff_link_check_archive_element): Likewise.
	* cofflink.c (coff_link_check_archive_element): Likewise.  Don't
	scan symbols, simply add archive element whenever h is undefined.
	(coff_link_check_ar_symbols): Delete.
	* ecoff.c (read_ext_syms_and_strs): Delete.
	(reread_ext_syms_and_strs): Delete.
	(ecoff_link_check_archive_element): Add h and name param.  Don't
	scan symbols, simply add based on h.  Use ecoff_link_add_object_symbols.
	* elflink.c (elf_link_is_defined_archive_symbol): Don't test
	archive_pass.
	(elf_link_add_archive_symbols): Delete "defined" array, merge
	functionality into "included".  Make "included" a char array.  Don't
	set or test archive_pass.
	* libbfd-in.h (_bfd_generic_link_add_archive_symbols): Update.
	* libbfd.h: Regenerate.

1 files changed, 10 insertions, 43 deletions

diff --git a/bfd/elflink.c b/bfd/elflink.c
index f8a2208..69a87a6 100644
--- a/bfd/elflink.c
+++ b/bfd/elflink.c
@@ -2931,13 +2931,6 @@ elf_link_is_defined_archive_symbol (bfd * abfd, carsym * symdef)
   if (! bfd_check_format (abfd, bfd_object))
     return FALSE;
 
-  /* If we have already included the element containing this symbol in the
-     link then we do not need to include it again.  Just claim that any symbol
-     it contains is not a definition, so that our caller will not decide to
-     (re)include this element.  */
-  if (abfd->archive_pass)
-    return FALSE;
-
   /* Select the appropriate symbol table.  */
   if ((abfd->flags & DYNAMIC) == 0 || elf_dynsymtab (abfd) == 0)
     hdr = &elf_tdata (abfd)->symtab_hdr;
@@ -4928,20 +4921,8 @@ _bfd_elf_archive_symbol_lookup (bfd *abfd,
 }
 
 /* Add symbols from an ELF archive file to the linker hash table.  We
-   don't use _bfd_generic_link_add_archive_symbols because of a
-   problem which arises on UnixWare.  The UnixWare libc.so is an
-   archive which includes an entry libc.so.1 which defines a bunch of
-   symbols.  The libc.so archive also includes a number of other
-   object files, which also define symbols, some of which are the same
-   as those defined in libc.so.1.  Correct linking requires that we
-   consider each object file in turn, and include it if it defines any
-   symbols we need.  _bfd_generic_link_add_archive_symbols does not do
-   this; it looks through the list of undefined symbols, and includes
-   any object file which defines them.  When this algorithm is used on
-   UnixWare, it winds up pulling in libc.so.1 early and defining a
-   bunch of symbols.  This means that some of the other objects in the
-   archive are not included in the link, which is incorrect since they
-   precede libc.so.1 in the archive.
+   don't use _bfd_generic_link_add_archive_symbols because we need to
+   handle versioned symbols.
 
    Fortunately, ELF archive handling is simpler than that done by
    _bfd_generic_link_add_archive_symbols, which has to allow for a.out
@@ -4956,8 +4937,7 @@ static bfd_boolean
 elf_link_add_archive_symbols (bfd *abfd, struct bfd_link_info *info)
 {
   symindex c;
-  bfd_boolean *defined = NULL;
-  bfd_boolean *included = NULL;
+  unsigned char *included = NULL;
   carsym *symdefs;
   bfd_boolean loop;
   bfd_size_type amt;
@@ -4981,11 +4961,10 @@ elf_link_add_archive_symbols (bfd *abfd, struct bfd_link_info *info)
   if (c == 0)
     return TRUE;
   amt = c;
-  amt *= sizeof (bfd_boolean);
-  defined = (bfd_boolean *) bfd_zmalloc (amt);
-  included = (bfd_boolean *) bfd_zmalloc (amt);
-  if (defined == NULL || included == NULL)
-    goto error_return;
+  amt *= sizeof (*included);
+  included = (unsigned char *) bfd_zmalloc (amt);
+  if (included == NULL)
+    return FALSE;
 
   symdefs = bfd_ardata (abfd)->symdefs;
   bed = get_elf_backend_data (abfd);
@@ -5010,7 +4989,7 @@ elf_link_add_archive_symbols (bfd *abfd, struct bfd_link_info *info)
 	  struct bfd_link_hash_entry *undefs_tail;
 	  symindex mark;
 
-	  if (defined[i] || included[i])
+	  if (included[i])
 	    continue;
 	  if (symdef->file_offset == last)
 	    {
@@ -5045,7 +5024,8 @@ elf_link_add_archive_symbols (bfd *abfd, struct bfd_link_info *info)
 	  else if (h->root.type != bfd_link_hash_undefined)
 	    {
 	      if (h->root.type != bfd_link_hash_undefweak)
-		defined[i] = TRUE;
+		/* Symbol must be defined.  Don't check it again.  */
+		included[i] = TRUE;
 	      continue;
 	    }
 
@@ -5057,16 +5037,6 @@ elf_link_add_archive_symbols (bfd *abfd, struct bfd_link_info *info)
 	  if (! bfd_check_format (element, bfd_object))
 	    goto error_return;
 
-	  /* Doublecheck that we have not included this object
-	     already--it should be impossible, but there may be
-	     something wrong with the archive.  */
-	  if (element->archive_pass != 0)
-	    {
-	      bfd_set_error (bfd_error_bad_value);
-	      goto error_return;
-	    }
-	  element->archive_pass = 1;
-
 	  undefs_tail = info->hash->undefs_tail;
 
 	  if (!(*info->callbacks
@@ -5104,14 +5074,11 @@ elf_link_add_archive_symbols (bfd *abfd, struct bfd_link_info *info)
     }
   while (loop);
 
-  free (defined);
   free (included);
 
   return TRUE;
 
  error_return:
-  if (defined != NULL)
-    free (defined);
   if (included != NULL)
     free (included);
   return FALSE;