path: root/trunk/src/rtld/dl-lookupX.h

/* Look up a symbol in the loaded objects.
   Copyright (C) 1995-2005, 2006, 2007, 2009, 2010
   Free Software Foundation, Inc.
   This file is part of the GNU C Library.

   The GNU C Library is free software; you can redistribute it and/or
   modify it under the terms of the GNU Lesser General Public
   License as published by the Free Software Foundation; either
   version 2.1 of the License, or (at your option) any later version.

   The GNU C Library is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
   Lesser General Public License for more details.

   You should have received a copy of the GNU Lesser General Public
   License along with the GNU C Library; if not, write to the Free
   Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
   02111-1307 USA.  */

/* This file is from eglibc 2.13, libc/elf/dl-lookup.c
   It has been split into two pieces dl-lookup.c and dl-lookupX.c,
   the purpose of the split is to enable both 32-bit and 64-bit ELF
   processing in the same application.  This file contains the ELF
   size specific routines.  It must be included from dl-lookup.c and
   not used directly!
 */

#if RTLD_ELF_SIZE == 32
  #define sym_val sym_val32
  #define do_lookup_x do_lookup_x32
  #undef _dl_setup_hash
  #define _dl_setup_hash rtld_setup_hash32
  #define _dl_debug_bindings rtld_debug_bindings32
  #define _dl_lookup_symbol_x rtld_lookup_symbol_x32

#elif RTLD_ELF_SIZE == 64
  #define sym_val sym_val64
  #define do_lookup_x do_lookup_x64
  #undef _dl_setup_hash
  #define _dl_setup_hash rtld_setup_hash64
  #define _dl_debug_bindings rtld_debug_bindings64
  #define _dl_lookup_symbol_x rtld_lookup_symbol_x64

#else
  #error "You must declare RTLD_ELF_SIZE to be either 32 or 64"
#endif

#define __ELF_NATIVE_CLASS RTLD_ELF_SIZE

/* From eglibc 2.13 - elf/link.h */

/* We use this macro to refer to ELF types independent of the native wordsize.
   `ElfW(TYPE)' is used in place of `Elf32_TYPE' or `Elf64_TYPE'.  */
#define ELFW(type)	_ElfW (ELF, __ELF_NATIVE_CLASS, type)
#define ElfW(type)      _ElfW (Elf, __ELF_NATIVE_CLASS, type)
#define _ElfW(e,w,t)    _ElfW_1 (e, w, _##t)
#define _ElfW_1(e,w,t)  e##w##t

struct sym_val
  {
    const ElfW(Sym) *s;
    struct ldlibs_link_map *m;
  };

/* Inner part of the lookup functions.  We return a value > 0 if we
   found the symbol, the value 0 if nothing is found and < 0 if
   something bad happened.  */
static int
do_lookup_x (const char *undef_name, uint_fast32_t new_hash,
	     unsigned long int *old_hash, const ElfW(Sym) *ref,
	     struct sym_val *result, struct r_scope_elem *scope, size_t i,
	     const struct r_found_version *const version, int flags,
	     struct ldlibs_link_map *skip, int type_class, struct ldlibs_link_map *undef_map)
{
  size_t n = scope->r_nlist;
  struct ldlibs_link_map **list = scope->r_list;

  do
    {
      /* These variables are used in the nested function.  */
      Elf_Symndx symidx;
      int num_versions = 0;
      const ElfW(Sym) *versioned_sym = NULL;

      const struct ldlibs_link_map *map = list[i];

      /* Here come the extra test needed for `_dl_lookup_symbol_skip'.  */
      if (map == skip)
	continue;

      /* Don't search the executable when resolving a copy reloc.  */
      if ((type_class & ELF_RTYPE_CLASS_COPY) && map->l_type == lt_executable)
	continue;

      /* Print some debugging info if wanted.  */
      if (__builtin_expect (GLRO_dl_debug_mask & DL_DEBUG_SYMBOLS, 0))
	_dl_debug_printf ("symbol=%s;  lookup in file=%s [%lu]\n",
			  undef_name,
			  map->l_name[0] ? map->l_name : rtld_progname,
			  0UL);

      /* If the hash table is empty there is nothing to do here.  */
      if (map->l_nbuckets == 0)
	continue;

      /* The tables for this map.  */
      const ElfW(Sym) *symtab = (const void *) D_PTR (map, l_info[DT_SYMTAB]);
      const char *strtab = (const void *) D_PTR (map, l_info[DT_STRTAB]);


      /* Nested routine to check whether the symbol matches.  */
      const ElfW(Sym) *
      __attribute_noinline__
      check_match (const ElfW(Sym) *sym)
      {
	unsigned int stt = ELFW(ST_TYPE) (sym->st_info);
	assert (ELF_RTYPE_CLASS_PLT == 1);
/* from mips dl-lookup.c */
	/* The semantics of zero/non-zero values of undefined symbols
	   differs depending on whether the non-PIC ABI is in use.
	   Under the non-PIC ABI, a non-zero value indicates that
	   there is an address reference to the symbol and thus it
	   must always be resolved (except when resolving a jump slot
	   relocation) to the PLT entry whose address is provided as
	   the symbol's value; a zero value indicates that this
	   canonical-address behaviour is not required.  Yet under the
	   classic MIPS psABI, a zero value indicates that there is an
	   address reference to the function and the dynamic linker
	   must resolve the symbol immediately upon loading.  To avoid
	   conflict, symbols for which the dynamic linker must assume
	   the non-PIC ABI semantics are marked with the STO_MIPS_PLT
	   flag.  */
/* end mips */
	if (__builtin_expect ((sym->st_value == 0 /* No value.  */
			       && stt != STT_TLS)
/* from mips dl-lookup.c */
			      || (map->machine == EM_MIPS
			        && sym->st_shndx == SHN_UNDEF
			        && !(sym->st_other & STO_MIPS_PLT))
/* end mips */
			      || (type_class & (sym->st_shndx == SHN_UNDEF)),
			      0))
	  return NULL;

	/* Ignore all but STT_NOTYPE, STT_OBJECT, STT_FUNC,
	   STT_COMMON, STT_TLS, and STT_GNU_IFUNC since these are no
	   code/data definitions.  */
#define ALLOWED_STT \
	((1 << STT_NOTYPE) | (1 << STT_OBJECT) | (1 << STT_FUNC) \
	 | (1 << STT_COMMON) | (1 << STT_TLS) | (1 << STT_GNU_IFUNC))
	if (__builtin_expect (((1 << stt) & ALLOWED_STT) == 0, 0))
	  return NULL;

	if (sym != ref && strcmp (strtab + sym->st_name, undef_name))
	  /* Not the symbol we are looking for.  */
	  return NULL;

	const ElfW(Half) *verstab = map->l_versyms;
	if (version != NULL)
	  {
	    if (__builtin_expect (verstab == NULL, 0))
	      {
		/* We need a versioned symbol but haven't found any.  If
		   this is the object which is referenced in the verneed
		   entry it is a bug in the library since a symbol must
		   not simply disappear.

		   It would also be a bug in the object since it means that
		   the list of required versions is incomplete and so the
		   tests in dl-version.c haven't found a problem.*/
		assert (version->filename == NULL
			|| ! _dl_name_match_p (version->filename, map));

		/* Otherwise we accept the symbol.  */
	      }
	    else
	      {
		/* We can match the version information or use the
		   default one if it is not hidden.  */
		ElfW(Half) ndx = verstab[symidx] & 0x7fff;
		if ((map->l_versions[ndx].hash != version->hash
		     || strcmp (map->l_versions[ndx].name, version->name))
		    && (version->hidden || map->l_versions[ndx].hash
			|| (verstab[symidx] & 0x8000)))
		  /* It's not the version we want.  */
		  return NULL;
	      }
	  }
	else
	  {
	    /* No specific version is selected.  There are two ways we
	       can got here:

	       - a binary which does not include versioning information
	       is loaded

	       - dlsym() instead of dlvsym() is used to get a symbol which
	       might exist in more than one form

	       If the library does not provide symbol version information
	       there is no problem at at: we simply use the symbol if it
	       is defined.

	       These two lookups need to be handled differently if the
	       library defines versions.  In the case of the old
	       unversioned application the oldest (default) version
	       should be used.  In case of a dlsym() call the latest and
	       public interface should be returned.  */
	    if (verstab != NULL)
	      {
		if ((verstab[symidx] & 0x7fff)
		    >= ((flags & DL_LOOKUP_RETURN_NEWEST) ? 2 : 3))
		  {
		    /* Don't accept hidden symbols.  */
		    if ((verstab[symidx] & 0x8000) == 0
			&& num_versions++ == 0)
		      /* No version so far.  */
		      versioned_sym = sym;

		    return NULL;
		  }
	      }
	  }

	/* There cannot be another entry for this symbol so stop here.  */
	return sym;
      }

      const ElfW(Sym) *sym;
      const ElfW(Addr) *bitmask = map->l_gnu_bitmask;
      if (__builtin_expect (bitmask != NULL, 1))
	{
	  ElfW(Addr) bitmask_word
	    = bitmask[(new_hash / __ELF_NATIVE_CLASS)
		      & map->l_gnu_bitmask_idxbits];

	  unsigned int hashbit1 = new_hash & (__ELF_NATIVE_CLASS - 1);
	  unsigned int hashbit2 = ((new_hash >> map->l_gnu_shift)
				   & (__ELF_NATIVE_CLASS - 1));

	  if (__builtin_expect ((bitmask_word >> hashbit1)
				& (bitmask_word >> hashbit2) & 1, 0))
	    {
	      Elf32_Word bucket = map->l_gnu_buckets[new_hash
						     % map->l_nbuckets];

/* PPC64 workaround */
	      /* There is a bad hash entry and it's pointing beyond
		 the end of the bucket list. */
	      assert ((void *)&map->l_gnu_chain_zero[bucket] < map->l_buckets_end);
/* END PPC64 workaround */
	      if (bucket != 0)
		{
		  const Elf32_Word *hasharr = &map->l_gnu_chain_zero[bucket];

		  do
		    if (((*hasharr ^ new_hash) >> 1) == 0)
		      {
			symidx = hasharr - map->l_gnu_chain_zero;
			sym = check_match (&symtab[symidx]);
			if (sym != NULL)
			  goto found_it;
		      }
		  while ((*hasharr++ & 1u) == 0);
		}
	    }
	  /* No symbol found.  */
	  symidx = SHN_UNDEF;
	}
      else
	{
	  if (*old_hash == 0xffffffff)
	    *old_hash = _dl_elf_hash (undef_name);

	  /* Use the old SysV-style hash table.  Search the appropriate
	     hash bucket in this object's symbol table for a definition
	     for the same symbol name.  */
	  for (symidx = map->l_buckets[*old_hash % map->l_nbuckets];
	       symidx != STN_UNDEF;
	       symidx = map->l_chain[symidx])
	    {
	      sym = check_match (&symtab[symidx]);
	      if (sym != NULL)
		goto found_it;
	    }
	}

      /* If we have seen exactly one versioned symbol while we are
	 looking for an unversioned symbol and the version is not the
	 default version we still accept this symbol since there are
	 no possible ambiguities.  */
      sym = num_versions == 1 ? versioned_sym : NULL;

      if (sym != NULL)
	{
	found_it:
	  switch (__builtin_expect (ELFW(ST_BIND) (sym->st_info), STB_GLOBAL))
	    {
	    case STB_WEAK:
	      /* Weak definition.  Use this value if we don't find another.  */
	      if (__builtin_expect (GLRO(dl_dynamic_weak), 0))
		{
		  if (! result->s)
		    {
		      result->s = sym;
		      result->m = (struct ldlibs_link_map *) map;
		    }
		  break;
		}
	      /* FALLTHROUGH */
	    case STB_GLOBAL:
	    success:
	      /* Global definition.  Just what we need.  */
	      result->s = sym;
	      result->m = (struct ldlibs_link_map *) map;
	      return 1;

	    case STB_GNU_UNIQUE:;
	      /* We have to determine whether we already found a
		 symbol with this name before.  If not then we have to
		 add it to the search table.  If we already found a
		 definition we have to use it.  */
	      void enter (struct unique_sym *table, size_t size,
			  unsigned int hash, const char *name,
			  const ElfW(Sym) *sym, struct link_map *map)
	      {
		size_t idx = hash % size;
		size_t hash2 = 1 + hash % (size - 2);
		while (1)
		  {
		    if (table[idx].name == NULL)
		      {
			table[idx].hashval = hash;
			table[idx].name = name;
			if ((type_class & ELF_RTYPE_CLASS_COPY) != 0)
			  {
			    table[idx].sym = ref;
			    table[idx].map = (struct link_map *) undef_map;
			  }
			else
			  {
			    table[idx].sym = sym;
			    table[idx].map = map;
			  }

			return;
		      }

		    idx += hash2;
		    if (idx >= size)
		      idx -= size;
		  }
	      }

	      struct unique_sym_table *tab
		= _ns_unique_sym_table;

	      struct unique_sym *entries = tab->entries;
	      size_t size = tab->size;
	      if (entries != NULL)
		{
		  size_t idx = new_hash % size;
		  size_t hash2 = 1 + new_hash % (size - 2);
		  while (1)
		    {
		      if (entries[idx].hashval == new_hash
			  && strcmp (entries[idx].name, undef_name) == 0)
			{
			  result->s = entries[idx].sym;
		          result->m = (struct ldlibs_link_map *) entries[idx].map;
			  return 1;
			}

		      if (entries[idx].name == NULL)
			break;

		      idx += hash2;
		      if (idx >= size)
			idx -= size;
		    }
		  if (size * 3 <= tab->n_elements * 4)
		    {
		      /* Expand the table.  */
		      size_t newsize;
		      struct unique_sym *newentries;
		      newsize = _dl_higher_prime_number (size + 1);
		      newentries = calloc (sizeof (struct unique_sym), newsize);
		      if (newentries == NULL)
			{
			nomem:
			  /* this is a goto target, so we have to be
			   * sure to initialize these values in case we
			   * got here from somewhere else.
			   */
			  newentries = NULL;
			  newsize = 0;
			  _dl_fatal_printf ("out of memory\n");
			}

		      for (idx = 0; idx < size; ++idx)
			if (entries[idx].name != NULL)
			  enter (newentries, newsize, entries[idx].hashval,
				 entries[idx].name, entries[idx].sym,
				 entries[idx].map);

		      tab->free (entries);
		      tab->size = newsize;
		      size = newsize;
		      entries = tab->entries = newentries;
		      tab->free = free;
		    }
		}
	      else
		{
		  /* If tab->entries is NULL, but tab->size is not, it means
		     this is the second, conflict finding, lookup for
		     LD_TRACE_PRELINKING in _dl_debug_bindings.  Don't
		     allocate anything and don't enter anything into the
		     hash table.  */
		  if (__builtin_expect (tab->size, 0))
		    {
		      assert (GLRO_dl_debug_mask & DL_DEBUG_PRELINK);
		      goto success;
		    }

#define INITIAL_NUNIQUE_SYM_TABLE 31
		  size = INITIAL_NUNIQUE_SYM_TABLE;
		  entries = calloc (sizeof (struct unique_sym), size);
		  if (entries == NULL)
		    goto nomem;

		  tab->entries = entries;
		  tab->size = size;
		  tab->free = free;
		}

	      enter (entries, size, new_hash, strtab + sym->st_name, sym,
		     (struct link_map *) map);
	      ++tab->n_elements;

	      goto success;

	    default:
	      /* Local symbols are ignored.  */
	      break;
	    }
	}

      /* If this current map is the one mentioned in the verneed entry
	 and we have not found a weak entry, it is a bug.  */
      if (symidx == STN_UNDEF && version != NULL && version->filename != NULL
	  && __builtin_expect (_dl_name_match_p (version->filename, map), 0))
	return -1;
    }
  while (++i < n);

  /* We have not found anything until now.  */
  return 0;
}


/* Cache the location of MAP's hash table.  */

void
_dl_setup_hash (struct ldlibs_link_map *map)
{
  Elf_Symndx *hash;
  Elf_Symndx nchain;

  if (__builtin_expect (map->l_info[DT_ADDRTAGIDX (DT_GNU_HASH) + DT_NUM
                                    + DT_THISPROCNUM + DT_VERSIONTAGNUM
                                    + DT_EXTRANUM + DT_VALNUM] != NULL, 1))
    {
      Elf32_Word *hash32
        = (void *) D_PTR (map, l_info[DT_ADDRTAGIDX (DT_GNU_HASH) + DT_NUM
                                      + DT_THISPROCNUM + DT_VERSIONTAGNUM
                                      + DT_EXTRANUM + DT_VALNUM]);
      map->l_nbuckets = *hash32++;
      Elf32_Word symbias = *hash32++;
      Elf32_Word bitmask_nwords = *hash32++;
      /* Must be a power of two.  */
      assert ((bitmask_nwords & (bitmask_nwords - 1)) == 0);
      map->l_gnu_bitmask_idxbits = bitmask_nwords - 1;
      map->l_gnu_shift = *hash32++;

      map->l_gnu_bitmask = (ElfW(Addr) *) hash32;
      hash32 += __ELF_NATIVE_CLASS / 32 * bitmask_nwords;

      map->l_gnu_buckets = hash32;
      hash32 += map->l_nbuckets;
      map->l_gnu_chain_zero = hash32 - symbias; 
      return;
    }

  if (!map->l_info[DT_HASH])
    return;
  hash = (void *) D_PTR (map, l_info[DT_HASH]);

  map->l_nbuckets = *hash++;
  nchain = *hash++;
  map->l_buckets = hash;
  hash += map->l_nbuckets;
  map->l_chain = hash;
}


static void
_dl_debug_bindings (const char *undef_name, struct ldlibs_link_map *undef_map,
		    const ElfW(Sym) **ref, struct sym_val *value,
		    const struct r_found_version *version, int type_class,
		    int protected);


/* Search loaded objects' symbol tables for a definition of the symbol
   UNDEF_NAME, perhaps with a requested version for the symbol.

   We must never have calls to the audit functions inside this function
   or in any function which gets called.  If this would happen the audit
   code might create a thread which can throw off all the scope locking.  */
lookup_t
_dl_lookup_symbol_x (const char *undef_name, struct ldlibs_link_map *undef_map,
		     const ElfW(Sym) **ref,
		     struct r_scope_elem *symbol_scope[],
		     const struct r_found_version *version,
		     int type_class, int flags, struct ldlibs_link_map *skip_map)
{
  const uint_fast32_t new_hash = dl_new_hash (undef_name);
  unsigned long int old_hash = 0xffffffff;
  struct sym_val current_value = { NULL, NULL };
  struct r_scope_elem **scope = symbol_scope;

  /* No other flag than DL_LOOKUP_ADD_DEPENDENCY or DL_LOOKUP_GSCOPE_LOCK
     is allowed if we look up a versioned symbol.  */
  assert (version == NULL
	  || (flags & ~(DL_LOOKUP_ADD_DEPENDENCY | DL_LOOKUP_GSCOPE_LOCK))
	     == 0);

  size_t i = 0;
  if (__builtin_expect (skip_map != NULL, 0))
    /* Search the relevant loaded objects for a definition.  */
    while ((*scope)->r_list[i] != skip_map)
      ++i;

  size_t start;

  /* Search the relevant loaded objects for a definition.  */
  for (start = i; *scope != NULL; start = 0, ++scope)
    {
      int res = do_lookup_x (undef_name, new_hash, &old_hash, *ref,
			     &current_value, *scope, start, version, flags,
			     skip_map, type_class, undef_map);
      if (res > 0)
	break;

      if (__builtin_expect (res, 0) < 0 && skip_map == NULL)
	{
	  /* Oh, oh.  The file named in the relocation entry does not
	     contain the needed symbol.  This code is never reached
	     for unversioned lookups.  */
	  assert (version != NULL);
	  const char *reference_name = undef_map ? undef_map->l_name : NULL;

	  /* XXX We cannot translate the message.  */
	  _dl_signal_cerror (0, (reference_name[0]
				 ? reference_name
				 : (rtld_progname ?: "<main program>")),
			     "relocation error",
			     make_string ("symbol ", undef_name, ", version ",
					  version->name,
					  " not defined in file ",
					  version->filename,
					  " with link time reference",
					  res == -2
					  ? " (no version symbols)" : ""));
	  *ref = NULL;
	  return 0;
	}
    }

  if (__builtin_expect (current_value.s == NULL, 0))
    {
      if ((*ref == NULL || ELFW(ST_BIND) ((*ref)->st_info) != STB_WEAK)
	  && skip_map == NULL)
	{
	  /* We could find no value for a strong reference.  */
	  const char *reference_name = undef_map ? undef_map->l_name : "";
	  const char *versionstr = version ? ", version " : "";
	  const char *versionname = (version && version->name
				     ? version->name : "");

	  /* XXX We cannot translate the message.  */
	  _dl_signal_cerror (0, (reference_name[0]
				 ? reference_name
				 : (rtld_progname ?: "<main program>")),
			     ("symbol lookup error"),
			     make_string (undefined_msg, undef_name,
					  versionstr, versionname));
	}
      *ref = NULL;
      return 0;
    }

  int protected = (*ref
		   && ELFW(ST_VISIBILITY) ((*ref)->st_other) == STV_PROTECTED);
  if (__builtin_expect (protected != 0, 0))
    {
      /* It is very tricky.  We need to figure out what value to
	 return for the protected symbol.  */
      if (type_class == ELF_RTYPE_CLASS_PLT)
	{
	  if (current_value.s != NULL && current_value.m != undef_map)
	    {
	      current_value.s = *ref;
	      current_value.m = undef_map;
	    }
	}
      else
	{
	  struct sym_val protected_value = { NULL, NULL };

	  for (scope = symbol_scope; *scope != NULL; i = 0, ++scope)
	    if (do_lookup_x (undef_name, new_hash, &old_hash, *ref,
			     &protected_value, *scope, i, version, flags,
			     skip_map, ELF_RTYPE_CLASS_PLT, NULL) != 0)
	      break;

	  if (protected_value.s != NULL && protected_value.m != undef_map)
	    {
	      current_value.s = *ref;
	      current_value.m = undef_map;
	    }
	}
    }

#if 0
  /* We have to check whether this would bind UNDEF_MAP to an object
     in the global scope which was dynamically loaded.  In this case
     we have to prevent the latter from being unloaded unless the
     UNDEF_MAP object is also unloaded.  */
  if (__builtin_expect (current_value.m->l_type == lt_loaded, 0)
      /* Don't do this for explicit lookups as opposed to implicit
	 runtime lookups.  */
      && (flags & DL_LOOKUP_ADD_DEPENDENCY) != 0
      )
      /* Something went wrong.  Perhaps the object we tried to reference
	 was just removed.  Try finding another definition.  */
      return _dl_lookup_symbol_x (undef_name, undef_map, ref,
				  symbol_scope,
				  version, type_class, flags, skip_map);
#endif

  if (__builtin_expect (GLRO_dl_debug_mask
			& (DL_DEBUG_BINDINGS|DL_DEBUG_PRELINK), 0))
    _dl_debug_bindings (undef_name, undef_map, ref,
			&current_value, version, type_class, protected);

  *ref = current_value.s;
  return LOOKUP_VALUE (current_value.m);
}

static void
_dl_debug_bindings (const char *undef_name, struct ldlibs_link_map *undef_map,
		    const ElfW(Sym) **ref, struct sym_val *value,
		    const struct r_found_version *version, int type_class,
		    int protected)
{
  const char *reference_name = undef_map->l_name;

  if (GLRO_dl_debug_mask & DL_DEBUG_BINDINGS)
    {
      _dl_debug_printf ("binding file %s [%lu] to %s [%lu]: %s symbol `%s'",
			(reference_name[0]
			 ? reference_name
			 : (rtld_progname ?: "<main program>")),
			0UL,
			value->m->l_name[0] ? value->m->l_name : rtld_progname,
			0UL,
			protected ? "protected" : "normal", undef_name);
      if (version)
	_dl_debug_printf (" [%s]\n", version->name);
      else
	_dl_debug_printf ("\n");
    }
  if (GLRO_dl_debug_mask & DL_DEBUG_PRELINK)
    {
      int conflict = 0;
      struct sym_val val = { NULL, NULL };

      /* We need to always process these or we can miss conflict symbols when
         RTLD_TRACE_PRELINKING=<library> */
      if (1)
	{
	  const uint_fast32_t new_hash = dl_new_hash (undef_name);
	  unsigned long int old_hash = 0xffffffff;
	  struct unique_sym *saved_entries
	    = _ns_unique_sym_table->entries;

	  _ns_unique_sym_table->entries = NULL;
	  do_lookup_x (undef_name, new_hash, &old_hash, *ref, &val,
		       undef_map->l_local_scope[0], 0, version, 0, NULL,
		       type_class, undef_map);
	  if (val.s != value->s || val.m != value->m)
	    conflict = 1;
	  else if (val.s
                   && __builtin_expect (ELFW(ST_BIND) (val.s->st_info),
                                        STB_GLOBAL) == STB_GNU_UNIQUE)
	   {
              /* If it is STB_GNU_UNIQUE and undef_map's l_local_scope
                 contains any DT_SYMBOLIC libraries, unfortunately there
                 can be conflicts even if the above is equal.  As symbol
                 resolution goes from the last library to the first and
                 if a STB_GNU_UNIQUE symbol is found in some late DT_SYMBOLIC
                 library, it would be the one that is looked up.  */
              struct sym_val val2 = { NULL, NULL };
              size_t n;
              struct r_scope_elem *scope = undef_map->l_local_scope[0];

              for (n = 0; n < scope->r_nlist; n++)
                if (scope->r_list[n] == val.m)
                  break;

              for (n++; n < scope->r_nlist; n++)
                if (scope->r_list[n]->l_info[DT_SYMBOLIC] != NULL
                    && do_lookup_x (undef_name, new_hash, &old_hash, *ref,
                                    &val2,
				    scope,
                                    0, version, 0, NULL, type_class,
                                    undef_map) > 0)

/*                                    &scope->r_list[n]->l_symbolic_searchlist,*/
                  {
                    conflict = 1;
                    val = val2;
                    break;
                  }
            }
	  _ns_unique_sym_table->entries = saved_entries;
	}

      if (value->s)
	{
	  if (__builtin_expect (ELFW(ST_TYPE) (value->s->st_info)
				== STT_TLS, 0))
	    type_class = 4;
	  else if (__builtin_expect (ELFW(ST_TYPE) (value->s->st_info)
				     == STT_GNU_IFUNC, 0))
	    type_class |= 8;
	}

      if (conflict
	  || GLRO(dl_trace_prelink_map) == undef_map
	  || GLRO(dl_trace_prelink_map) == NULL
	  || type_class >= 4)
	{
	  printf ("%s 0x%0*Zx 0x%0*Zx -> 0x%0*Zx 0x%0*Zx ",
		      conflict ? "conflict" : "lookup",
		      (int) sizeof (ElfW(Addr)) * 2,
		      (size_t) undef_map->l_map_start,
		      (int) sizeof (ElfW(Addr)) * 2,
		      (size_t) (((char *)*ref) - ((char *)undef_map->l_info[DT_SYMTAB]) + (char *)undef_map->sym_base),
		      (int) sizeof (ElfW(Addr)) * 2,
		      (size_t) (value->s ? value->m->l_map_start : 0),
		      (int) sizeof (ElfW(Addr)) * 2,
		      (size_t) (value->s ? value->s->st_value : 0));

	  if (conflict)
	    printf ("x 0x%0*Zx 0x%0*Zx ",
			(int) sizeof (ElfW(Addr)) * 2,
			(size_t) (val.s ? val.m->l_map_start : 0),
			(int) sizeof (ElfW(Addr)) * 2,
			(size_t) (val.s ? val.s->st_value : 0));

	  printf ("/%x %s\n", type_class, undef_name);
	}
    }
/* #endif */
}

#undef sym_val
#undef do_lookup_x
#undef _dl_setup_hash
#define _dl_setup_hash rtld_setup_hash
#undef _dl_debug_bindings
#undef _dl_lookup_symbol_x