Move mips from ports to libc.

I've moved the MIPS port from ports to the main sysdeps hierarchy.
Beyond the README update, the move of the files was simply

git mv ports/sysdeps/mips sysdeps/mips
git mv ports/sysdeps/unix/mips sysdeps/unix/mips
git mv ports/sysdeps/unix/sysv/linux/mips sysdeps/unix/sysv/linux/mips

and in addition to the ChangeLog entries here, I put a note at the top
of ports/ChangeLog.mips similar to those in other files.

Tested that disassembly of installed shared libraries for mips is the
same before and after this patch (except for ld.so where paths in
assertions are involved, as for arm).

	* sysdeps/mips: Move directory from ports/sysdeps/mips.
	* sysdeps/unix/mips: Move directory from ports/sysdeps/unix/mips.
	* sysdeps/unix/sysv/linux/mips: Move directory from
	ports/sysdeps/unix/sysv/linux/mips.
	* README: Update listing for mips-*-linux-gnu and
	mips64-*-linux-gnu.

	* sysdeps/mips: Move directory to ../sysdeps/mips.
	* sysdeps/unix/mips: Move directory to ../sysdeps/unix/mips.
	* sysdeps/unix/sysv/linux/mips: Move directory to
	../sysdeps/unix/sysv/linux/mips.

1 files changed, 1029 insertions, 0 deletions

diff --git a/sysdeps/mips/dl-lookup.c b/sysdeps/mips/dl-lookup.c
new file mode 100644
index 0000000000..bda0c522b2
--- /dev/null
+++ b/sysdeps/mips/dl-lookup.c
@@ -0,0 +1,1029 @@
+/* Look up a symbol in the loaded objects.
+   MIPS/Linux version - special handling of non-PIC undefined symbol rules.
+   Copyright (C) 1995-2014 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, see
+   <http://www.gnu.org/licenses/>.  */
+
+#include <alloca.h>
+#include <libintl.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+#include <ldsodefs.h>
+#include <dl-hash.h>
+#include <dl-machine.h>
+#include <sysdep-cancel.h>
+#include <bits/libc-lock.h>
+#include <tls.h>
+#include <atomic.h>
+
+#include <assert.h>
+
+#define VERSTAG(tag)	(DT_NUM + DT_THISPROCNUM + DT_VERSIONTAGIDX (tag))
+
+/* We need this string more than once.  */
+static const char undefined_msg[] = "undefined symbol: ";
+
+
+struct sym_val
+  {
+    const ElfW(Sym) *s;
+    struct link_map *m;
+  };
+
+
+#define make_string(string, rest...) \
+  ({									      \
+    const char *all[] = { string, ## rest };				      \
+    size_t len, cnt;							      \
+    char *result, *cp;							      \
+									      \
+    len = 1;								      \
+    for (cnt = 0; cnt < sizeof (all) / sizeof (all[0]); ++cnt)		      \
+      len += strlen (all[cnt]);						      \
+									      \
+    cp = result = alloca (len);						      \
+    for (cnt = 0; cnt < sizeof (all) / sizeof (all[0]); ++cnt)		      \
+      cp = __stpcpy (cp, all[cnt]);					      \
+									      \
+    result;								      \
+  })
+
+/* Statistics function.  */
+#ifdef SHARED
+# define bump_num_relocations() ++GL(dl_num_relocations)
+#else
+# define bump_num_relocations() ((void) 0)
+#endif
+
+
+/* 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
+__attribute_noinline__
+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 link_map *skip, int type_class, struct link_map *undef_map)
+{
+  size_t n = scope->r_nlist;
+  /* Make sure we read the value before proceeding.  Otherwise we
+     might use r_list pointing to the initial scope and r_nlist being
+     the value after a resize.  That is the only path in dl-open.c not
+     protected by GSCOPE.  A read barrier here might be to expensive.  */
+  __asm volatile ("" : "+r" (n), "+m" (scope->r_list));
+  struct 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 link_map *map = list[i]->l_real;
+
+      /* 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;
+
+      /* Do not look into objects which are going to be removed.  */
+      if (map->l_removed)
+	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, DSO_FILENAME (map->l_name),
+			  map->l_ns);
+
+      /* 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);
+	/* 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.  */
+	if (__builtin_expect ((sym->st_value == 0 /* No value.  */
+			       && stt != STT_TLS)
+			      || (sym->st_shndx == SHN_UNDEF
+				  && !(sym->st_other & STO_MIPS_PLT))
+			      || (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 all: 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];
+	      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 link_map *) map;
+		    }
+		  break;
+		}
+	      /* FALLTHROUGH */
+	    case STB_GLOBAL:
+	    success:
+	      /* Global definition.  Just what we need.  */
+	      result->s = sym;
+	      result->m = (struct 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, const struct link_map *map)
+	      {
+		size_t idx = hash % size;
+		size_t hash2 = 1 + hash % (size - 2);
+		while (table[idx].name != NULL)
+		  {
+		    idx += hash2;
+		    if (idx >= size)
+		      idx -= size;
+		  }
+
+		table[idx].hashval = hash;
+		table[idx].name = name;
+		table[idx].sym = sym;
+		table[idx].map = map;
+	      }
+
+	      struct unique_sym_table *tab
+		= &GL(dl_ns)[map->l_ns]._ns_unique_sym_table;
+
+	      __rtld_lock_lock_recursive (tab->lock);
+
+	      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)
+			{
+			  if ((type_class & ELF_RTYPE_CLASS_COPY) != 0)
+			    {
+			      /* We possibly have to initialize the central
+				 copy from the copy addressed through the
+				 relocation.  */
+			      result->s = sym;
+			      result->m = (struct link_map *) map;
+			    }
+			  else
+			    {
+			      result->s = entries[idx].sym;
+			      result->m = (struct link_map *) entries[idx].map;
+			    }
+			  __rtld_lock_unlock_recursive (tab->lock);
+			  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.  */
+#ifdef RTLD_CHECK_FOREIGN_CALL
+		      /* This must not happen during runtime relocations.  */
+		      assert (!RTLD_CHECK_FOREIGN_CALL);
+#endif
+		      size_t newsize = _dl_higher_prime_number (size + 1);
+		      struct unique_sym *newentries
+			= calloc (sizeof (struct unique_sym), newsize);
+		      if (newentries == NULL)
+			{
+			nomem:
+			  __rtld_lock_unlock_recursive (tab->lock);
+			  _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
+		{
+#ifdef RTLD_CHECK_FOREIGN_CALL
+		  /* This must not happen during runtime relocations.  */
+		  assert (!RTLD_CHECK_FOREIGN_CALL);
+#endif
+
+#ifdef SHARED
+		  /* 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);
+		      __rtld_lock_unlock_recursive (tab->lock);
+		      goto success;
+		    }
+#endif
+
+#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;
+		}
+
+	      if ((type_class & ELF_RTYPE_CLASS_COPY) != 0)
+		enter (entries, size, new_hash, strtab + sym->st_name, ref,
+		       undef_map);
+	      else
+		{
+		  enter (entries, size, new_hash, strtab + sym->st_name, sym,
+			 map);
+
+		  if (map->l_type == lt_loaded)
+		    /* Make sure we don't unload this object by
+		       setting the appropriate flag.  */
+		    ((struct link_map *) map)->l_flags_1 |= DF_1_NODELETE;
+		}
+	      ++tab->n_elements;
+
+	      __rtld_lock_unlock_recursive (tab->lock);
+
+	      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;
+}
+
+
+static uint_fast32_t
+dl_new_hash (const char *s)
+{
+  uint_fast32_t h = 5381;
+  for (unsigned char c = *s; c != '\0'; c = *++s)
+    h = h * 33 + c;
+  return h & 0xffffffff;
+}
+
+
+/* Add extra dependency on MAP to UNDEF_MAP.  */
+static int
+internal_function
+add_dependency (struct link_map *undef_map, struct link_map *map, int flags)
+{
+  struct link_map *runp;
+  unsigned int i;
+  int result = 0;
+
+  /* Avoid self-references and references to objects which cannot be
+     unloaded anyway.  */
+  if (undef_map == map)
+    return 0;
+
+  /* Avoid references to objects which cannot be unloaded anyway.  */
+  assert (map->l_type == lt_loaded);
+  if ((map->l_flags_1 & DF_1_NODELETE) != 0)
+    return 0;
+
+  struct link_map_reldeps *l_reldeps
+    = atomic_forced_read (undef_map->l_reldeps);
+
+  /* Make sure l_reldeps is read before l_initfini.  */
+  atomic_read_barrier ();
+
+  /* Determine whether UNDEF_MAP already has a reference to MAP.  First
+     look in the normal dependencies.  */
+  struct link_map **l_initfini = atomic_forced_read (undef_map->l_initfini);
+  if (l_initfini != NULL)
+    {
+      for (i = 0; l_initfini[i] != NULL; ++i)
+	if (l_initfini[i] == map)
+	  return 0;
+    }
+
+  /* No normal dependency.  See whether we already had to add it
+     to the special list of dynamic dependencies.  */
+  unsigned int l_reldepsact = 0;
+  if (l_reldeps != NULL)
+    {
+      struct link_map **list = &l_reldeps->list[0];
+      l_reldepsact = l_reldeps->act;
+      for (i = 0; i < l_reldepsact; ++i)
+	if (list[i] == map)
+	  return 0;
+    }
+
+  /* Save serial number of the target MAP.  */
+  unsigned long long serial = map->l_serial;
+
+  /* Make sure nobody can unload the object while we are at it.  */
+  if (__builtin_expect (flags & DL_LOOKUP_GSCOPE_LOCK, 0))
+    {
+      /* We can't just call __rtld_lock_lock_recursive (GL(dl_load_lock))
+	 here, that can result in ABBA deadlock.  */
+      THREAD_GSCOPE_RESET_FLAG ();
+      __rtld_lock_lock_recursive (GL(dl_load_lock));
+      /* While MAP value won't change, after THREAD_GSCOPE_RESET_FLAG ()
+	 it can e.g. point to unallocated memory.  So avoid the optimizer
+	 treating the above read from MAP->l_serial as ensurance it
+	 can safely dereference it.  */
+      map = atomic_forced_read (map);
+
+      /* From this point on it is unsafe to dereference MAP, until it
+	 has been found in one of the lists.  */
+
+      /* Redo the l_initfini check in case undef_map's l_initfini
+	 changed in the mean time.  */
+      if (undef_map->l_initfini != l_initfini
+	  && undef_map->l_initfini != NULL)
+	{
+	  l_initfini = undef_map->l_initfini;
+	  for (i = 0; l_initfini[i] != NULL; ++i)
+	    if (l_initfini[i] == map)
+	      goto out_check;
+	}
+
+      /* Redo the l_reldeps check if undef_map's l_reldeps changed in
+	 the mean time.  */
+      if (undef_map->l_reldeps != NULL)
+	{
+	  if (undef_map->l_reldeps != l_reldeps)
+	    {
+	      struct link_map **list = &undef_map->l_reldeps->list[0];
+	      l_reldepsact = undef_map->l_reldeps->act;
+	      for (i = 0; i < l_reldepsact; ++i)
+		if (list[i] == map)
+		  goto out_check;
+	    }
+	  else if (undef_map->l_reldeps->act > l_reldepsact)
+	    {
+	      struct link_map **list
+		= &undef_map->l_reldeps->list[0];
+	      i = l_reldepsact;
+	      l_reldepsact = undef_map->l_reldeps->act;
+	      for (; i < l_reldepsact; ++i)
+		if (list[i] == map)
+		  goto out_check;
+	    }
+	}
+    }
+  else
+    __rtld_lock_lock_recursive (GL(dl_load_lock));
+
+  /* The object is not yet in the dependency list.  Before we add
+     it make sure just one more time the object we are about to
+     reference is still available.  There is a brief period in
+     which the object could have been removed since we found the
+     definition.  */
+  runp = GL(dl_ns)[undef_map->l_ns]._ns_loaded;
+  while (runp != NULL && runp != map)
+    runp = runp->l_next;
+
+  if (runp != NULL)
+    {
+      /* The object is still available.  */
+
+      /* MAP could have been dlclosed, freed and then some other dlopened
+	 library could have the same link_map pointer.  */
+      if (map->l_serial != serial)
+	goto out_check;
+
+      /* Redo the NODELETE check, as when dl_load_lock wasn't held
+	 yet this could have changed.  */
+      if ((map->l_flags_1 & DF_1_NODELETE) != 0)
+	goto out;
+
+      /* If the object with the undefined reference cannot be removed ever
+	 just make sure the same is true for the object which contains the
+	 definition.  */
+      if (undef_map->l_type != lt_loaded
+	  || (undef_map->l_flags_1 & DF_1_NODELETE) != 0)
+	{
+	  map->l_flags_1 |= DF_1_NODELETE;
+	  goto out;
+	}
+
+      /* Add the reference now.  */
+      if (__builtin_expect (l_reldepsact >= undef_map->l_reldepsmax, 0))
+	{
+	  /* Allocate more memory for the dependency list.  Since this
+	     can never happen during the startup phase we can use
+	     `realloc'.  */
+	  struct link_map_reldeps *newp;
+	  unsigned int max
+	    = undef_map->l_reldepsmax ? undef_map->l_reldepsmax * 2 : 10;
+
+#ifdef RTLD_PREPARE_FOREIGN_CALL
+	  RTLD_PREPARE_FOREIGN_CALL;
+#endif
+
+	  newp = malloc (sizeof (*newp) + max * sizeof (struct link_map *));
+	  if (newp == NULL)
+	    {
+	      /* If we didn't manage to allocate memory for the list this is
+		 no fatal problem.  We simply make sure the referenced object
+		 cannot be unloaded.  This is semantically the correct
+		 behavior.  */
+	      map->l_flags_1 |= DF_1_NODELETE;
+	      goto out;
+	    }
+	  else
+	    {
+	      if (l_reldepsact)
+		memcpy (&newp->list[0], &undef_map->l_reldeps->list[0],
+			l_reldepsact * sizeof (struct link_map *));
+	      newp->list[l_reldepsact] = map;
+	      newp->act = l_reldepsact + 1;
+	      atomic_write_barrier ();
+	      void *old = undef_map->l_reldeps;
+	      undef_map->l_reldeps = newp;
+	      undef_map->l_reldepsmax = max;
+	      if (old)
+		_dl_scope_free (old);
+	    }
+	}
+      else
+	{
+	  undef_map->l_reldeps->list[l_reldepsact] = map;
+	  atomic_write_barrier ();
+	  undef_map->l_reldeps->act = l_reldepsact + 1;
+	}
+
+      /* Display information if we are debugging.  */
+      if (__builtin_expect (GLRO(dl_debug_mask) & DL_DEBUG_FILES, 0))
+	_dl_debug_printf ("\
+\nfile=%s [%lu];  needed by %s [%lu] (relocation dependency)\n\n",
+			  DSO_FILENAME (map->l_name),
+			  map->l_ns,
+			  DSO_FILENAME (undef_map->l_name),
+			  undef_map->l_ns);
+    }
+  else
+    /* Whoa, that was bad luck.  We have to search again.  */
+    result = -1;
+
+ out:
+  /* Release the lock.  */
+  __rtld_lock_unlock_recursive (GL(dl_load_lock));
+
+  if (__builtin_expect (flags & DL_LOOKUP_GSCOPE_LOCK, 0))
+    THREAD_GSCOPE_SET_FLAG ();
+
+  return result;
+
+ out_check:
+  if (map->l_serial != serial)
+    result = -1;
+  goto out;
+}
+
+static void
+internal_function
+_dl_debug_bindings (const char *undef_name, struct 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
+internal_function
+_dl_lookup_symbol_x (const char *undef_name, struct 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 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;
+
+  bump_num_relocations ();
+
+  /* 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;
+
+  /* Search the relevant loaded objects for a definition.  */
+  for (size_t 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 : "";
+
+	  /* XXX We cannot translate the message.  */
+	  _dl_signal_cerror (0, DSO_FILENAME (reference_name),
+			     N_("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
+	  && !(GLRO(dl_debug_mask) & DL_DEBUG_UNUSED))
+	{
+	  /* 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, DSO_FILENAME (reference_name),
+			     N_("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;
+	    }
+	}
+    }
+
+  /* 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
+      /* Add UNDEF_MAP to the dependencies.  */
+      && add_dependency (undef_map, current_value.m, flags) < 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,
+				  (flags & DL_LOOKUP_GSCOPE_LOCK)
+				  ? undef_map->l_scope : symbol_scope,
+				  version, type_class, flags, skip_map);
+
+  /* The object is used.  */
+  if (__builtin_expect (current_value.m->l_used == 0, 0))
+    current_value.m->l_used = 1;
+
+  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);
+}
+
+
+/* Cache the location of MAP's hash table.  */
+
+void
+internal_function
+_dl_setup_hash (struct link_map *map)
+{
+  Elf_Symndx *hash;
+
+  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++;
+  /* Skip nchain.  */
+  hash++;
+  map->l_buckets = hash;
+  hash += map->l_nbuckets;
+  map->l_chain = hash;
+}
+
+
+static void
+internal_function
+_dl_debug_bindings (const char *undef_name, struct 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'",
+			DSO_FILENAME (reference_name),
+			undef_map->l_ns,
+			DSO_FILENAME (value->m->l_name),
+			value->m->l_ns,
+			protected ? "protected" : "normal", undef_name);
+      if (version)
+	_dl_debug_printf_c (" [%s]\n", version->name);
+      else
+	_dl_debug_printf_c ("\n");
+    }
+#ifdef SHARED
+  if (GLRO(dl_debug_mask) & DL_DEBUG_PRELINK)
+    {
+      int conflict = 0;
+      struct sym_val val = { NULL, NULL };
+
+      if ((GLRO(dl_trace_prelink_map) == NULL
+	   || GLRO(dl_trace_prelink_map) == GL(dl_ns)[LM_ID_BASE]._ns_loaded)
+	  && undef_map != GL(dl_ns)[LM_ID_BASE]._ns_loaded)
+	{
+	  const uint_fast32_t new_hash = dl_new_hash (undef_name);
+	  unsigned long int old_hash = 0xffffffff;
+	  struct unique_sym *saved_entries
+	    = GL(dl_ns)[LM_ID_BASE]._ns_unique_sym_table.entries;
+
+	  GL(dl_ns)[LM_ID_BASE]._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 (__builtin_expect (undef_map->l_symbolic_in_local_scope, 0)
+		   && 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->r_list[n]->l_symbolic_searchlist,
+				    0, version, 0, NULL, type_class,
+				    undef_map) > 0)
+		  {
+		    conflict = 1;
+		    val = val2;
+		    break;
+		  }
+	    }
+	  GL(dl_ns)[LM_ID_BASE]._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)
+	{
+	  _dl_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) (((ElfW(Addr)) *ref) - undef_map->l_map_start),
+		      (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)
+	    _dl_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));
+
+	  _dl_printf ("/%x %s\n", type_class, undef_name);
+	}
+    }
+#endif
+}