[glibc.git] / elf / rtld.c

/* Run time dynamic linker.
Copyright (C) 1995 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 Library General Public License as
published by the Free Software Foundation; either version 2 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
Library General Public License for more details.

You should have received a copy of the GNU Library General Public
License along with the GNU C Library; see the file COPYING.LIB.  If
not, write to the Free Software Foundation, Inc., 675 Mass Ave,
Cambridge, MA 02139, USA.  */

#include <link.h>
#include "dynamic-link.h"
#include <stddef.h>
#include <stdlib.h>
#include <unistd.h>


#ifdef RTLD_START
RTLD_START
#else
#error "sysdeps/MACHINE/dl-machine.h fails to define RTLD_START"
#endif

/* System-specific function to do initial startup for the dynamic linker.
   After this, file access calls and getenv must work.  This is responsible
   for setting _dl_secure if we need to be secure (e.g. setuid),
   and for setting _dl_argc and _dl_argv, and then calling _dl_main.  */
extern Elf32_Addr _dl_sysdep_start (void **start_argptr,
				    void (*dl_main) (const Elf32_Phdr *phdr,
						     Elf32_Word phent,
						     Elf32_Addr *user_entry));

int _dl_secure;
int _dl_argc;
char **_dl_argv;

struct r_debug dl_r_debug;

static void dl_main (const Elf32_Phdr *phdr,
		     Elf32_Word phent,
		     Elf32_Addr *user_entry);

Elf32_Addr
_dl_start (void *arg)
{
  struct link_map rtld_map;

  /* Figure out the run-time load address of the dynamic linker itself.  */
  rtld_map.l_addr = elf_machine_load_address ();

  /* Read our own dynamic section and fill in the info array.
     Conveniently, the first element of the GOT contains the
     offset of _DYNAMIC relative to the run-time load address.  */
  rtld_map.l_ld = (void *) rtld_map.l_addr + *elf_machine_got ();
  elf_get_dynamic_info (rtld_map.l_ld, rtld_map.l_info);

#ifdef ELF_MACHINE_BEFORE_RTLD_RELOC
  ELF_MACHINE_BEFORE_RTLD_RELOC (rtld_map.l_info);
#endif

  /* Relocate ourselves so we can do normal function calls and
     data access using the global offset table.  */

  /* We must initialize `l_type' to make sure it is not `lt_interpreter'.
     That is the type to describe us, but not during bootstrapping--it
     indicates to elf_machine_rel{,a} that we were already relocated during
     bootstrapping, so it must anti-perform each bootstrapping relocation
     before applying the final relocation when ld.so is linked in as
     normal a shared library.  */
  rtld_map.l_type = lt_library;
  ELF_DYNAMIC_RELOCATE (&rtld_map, 0, NULL);


  /* Now life is sane; we can call functions and access global data.
     Set up to use the operating system facilities, and find out from
     the operating system's program loader where to find the program
     header table in core.  */

  dl_r_debug.r_ldbase = rtld_map.l_addr; /* Record our load address.  */

  /* Call the OS-dependent function to set up life so we can do things like
     file access.  It will call `dl_main' (below) to do all the real work
     of the dynamic linker, and then unwind our frame and run the user
     entry point on the same stack we entered on.  */
  return _dl_sysdep_start (&arg, &dl_main);
}


/* Now life is peachy; we can do all normal operations.
   On to the real work.  */

void _start (void);

static int rtld_command;	/* Nonzero if we were run directly.  */

static void
dl_main (const Elf32_Phdr *phdr,
	 Elf32_Word phent,
	 Elf32_Addr *user_entry)
{
  void doit (void)
    {
      const Elf32_Phdr *ph;
      struct link_map *l;
      const char *interpreter_name;
      int lazy;

      if (*user_entry == (Elf32_Addr) &_start)
	{
	  /* Ho ho.  We are not the program interpreter!  We are the program
	     itself!  This means someone ran ld.so as a command.  Well, that
	     might be convenient to do sometimes.  We support it by
	     interpreting the args like this:
	     
	     ld.so PROGRAM ARGS...
	     
	     The first argument is the name of a file containing an ELF
	     executable we will load and run with the following arguments.
	     To simplify life here, PROGRAM is searched for using the
	     normal rules for shared objects, rather than $PATH or anything
	     like that.  We just load it and use its entry point; we don't
	     pay attention to its PT_INTERP command (we are the interpreter
	     ourselves).  This is an easy way to test a new ld.so before
	     installing it.  */
	  if (_dl_argc < 2)
	    _dl_sysdep_fatal ("\
Usage: ld.so EXECUTABLE-FILE [ARGS-FOR-PROGRAM...]\n\
You have invoked `ld.so', the helper program for shared library executables.\n\
This program usually lives in the file `/lib/ld.so', and special directives\n\
in executable files using ELF shared libraries tell the system's program\n\
loader to load the helper program from this file.  This helper program loads\n\
the shared libraries needed by the program executable, prepares the program\n\
to run, and runs it.  You may invoke this helper program directly from the\n\
command line to load and run an ELF executable file; this is like executing\n\
that file itself, but always uses this helper program from the file you\n\
specified, instead of the helper program file specified in the executable\n\
file you run.  This is mostly of use for maintainers to test new versions\n\
of this helper program; chances are you did not intend to run this program.\n",
			      NULL);

	  rtld_command = 1;
	  interpreter_name = _dl_argv[0];
	  --_dl_argc;
	  ++_dl_argv;
	  l = _dl_map_object (NULL, _dl_argv[0], user_entry);
	  phdr = l->l_phdr;
	  phent = l->l_phnum;
	  l->l_type = lt_executable;
	  l->l_libname = (char *) "";
	}
      else
	{
	  /* Create a link_map for the executable itself.
	     This will be what dlopen on "" returns.  */
	  l = _dl_new_object ((char *) "", "", lt_executable);
	  l->l_phdr = phdr;
	  l->l_phnum = phent;
	  interpreter_name = 0;
	}

      /* Scan the program header table for the dynamic section.  */
      for (ph = phdr; ph < &phdr[phent]; ++ph)
	switch (ph->p_type)
	  {
	  case PT_DYNAMIC:
	    /* This tells us where to find the dynamic section,
	       which tells us everything we need to do.  */
	    l->l_ld = (void *) l->l_addr + ph->p_vaddr;
	    break;
	  case PT_INTERP:
	    /* This "interpreter segment" was used by the program loader to
	       find the program interpreter, which is this program itself, the
	       dynamic linker.  We note what name finds us, so that a future
	       dlopen call or DT_NEEDED entry, for something that wants to link
	       against the dynamic linker as a shared library, will know that
	       the shared object is already loaded.  */
	    interpreter_name = (void *) l->l_addr + ph->p_vaddr;
	    break;
	  }
      assert (interpreter_name); /* How else did we get here?  */

      /* Extract the contents of the dynamic section for easy access.  */
      elf_get_dynamic_info (l->l_ld, l->l_info);
      /* Set up our cache of pointers into the hash table.  */
      _dl_setup_hash (l);

      if (l->l_info[DT_DEBUG])
	/* There is a DT_DEBUG entry in the dynamic section.  Fill it in
	   with the run-time address of the r_debug structure, which we
	   will set up later to communicate with the debugger.  */
	l->l_info[DT_DEBUG]->d_un.d_ptr = (Elf32_Addr) &dl_r_debug;

      l = _dl_new_object ((char *) interpreter_name, interpreter_name,
			  lt_interpreter);

      /* Now process all the DT_NEEDED entries and map in the objects.
	 Each new link_map will go on the end of the chain, so we will
	 come across it later in the loop to map in its dependencies.  */
      for (l = _dl_loaded; l; l = l->l_next)
	{
	  if (l->l_info[DT_NEEDED])
	    {
	      const char *strtab
		= (void *) l->l_addr + l->l_info[DT_STRTAB]->d_un.d_ptr;
	      const Elf32_Dyn *d;
	      for (d = l->l_ld; d->d_tag != DT_NULL; ++d)
		if (d->d_tag == DT_NEEDED)
		  _dl_map_object (l, strtab + d->d_un.d_val, NULL);
	    }
	  l->l_deps_loaded = 1;
	}

      l = _dl_loaded->l_next;
      assert (l->l_type == lt_interpreter);
      if (l->l_opencount == 0)
	{
	  /* No DT_NEEDED entry referred to the interpreter object itself.
	     Remove it from the maps we will use for symbol resolution.  */
	  l->l_prev->l_next = l->l_next;
	  if (l->l_next)
	    l->l_next->l_prev = l->l_prev;
	}

      lazy = !_dl_secure && *(getenv ("LD_BIND_NOW") ?: "") == '\0';

      /* Now we have all the objects loaded.  Relocate them all.
	 We do this in reverse order so that copy relocs of earlier
	 objects overwrite the data written by later objects.  */
      l = _dl_loaded;
      while (l->l_next)
	l = l->l_next;
      do
	{
	  _dl_relocate_object (l, lazy);
	  l = l->l_prev;
	} while (l);

      /* Tell the debugger where to find the map of loaded objects.  */
      dl_r_debug.r_version = 1	/* R_DEBUG_VERSION XXX */;
      dl_r_debug.r_map = _dl_loaded;
      dl_r_debug.r_brk = (Elf32_Addr) &_dl_r_debug_state;
    }
  const char *errstring;
  const char *errobj;
  int err;

  err = _dl_catch_error (&errstring, &errobj, &doit);
  if (errstring)
    _dl_sysdep_fatal (_dl_argv[0] ?: "<program name unknown>",
		      ": error in loading shared libraries\n",
		      errobj ?: "", errobj ? ": " : "",
		      errstring, err ? ": " : NULL,
		      err ? strerror (err) : NULL, NULL);

  /* Once we return, _dl_sysdep_start will invoke
     the DT_INIT functions and then *USER_ENTRY.  */
}

/* This function exists solely to have a breakpoint set on it by the 
   debugger.  */
void
_dl_r_debug_state (void)
{
}
\f
#ifndef NDEBUG

/* Define (weakly) our own assert failure function which doesn't use stdio.
   If we are linked into the user program (-ldl), the normal __assert_fail
   defn can override this one.  */

#include "../stdio/_itoa.h"

void
__assert_fail (const char *assertion,
	       const char *file, unsigned int line, const char *function)
{
  char buf[64];
  buf[sizeof buf - 1] = '\0';
  _dl_sysdep_fatal ("BUG IN DYNAMIC LINKER ld.so: ",
		    file, ": ", _itoa (line, buf + sizeof buf - 1, 10, 0),
		    ": ", function ?: "", function ? ": " : "",
		    "Assertion `", assertion, "' failed!\n",
		    NULL);

}
weak_symbol (__assert_fail)

void
__assert_perror_fail (int errnum,
		      const char *file, unsigned int line,
		      const char *function)
{
  char buf[64];
  buf[sizeof buf - 1] = '\0';
  _dl_sysdep_fatal ("BUG IN DYNAMIC LINKER ld.so: ",
		    file, ": ", _itoa (line, buf + sizeof buf - 1, 10, 0),
		    ": ", function ?: "", function ? ": " : "",
		    "Unexpected error: ", strerror (errnum), "\n", NULL);

}
weak_symbol (__assert_perror_fail)

#endif
Commit	Line	Data
d66e34cd RM	1	/* Run time dynamic linker.
	2	Copyright (C) 1995 Free Software Foundation, Inc.
	3	This file is part of the GNU C Library.
	4
	5	The GNU C Library is free software; you can redistribute it and/or
	6	modify it under the terms of the GNU Library General Public License as
	7	published by the Free Software Foundation; either version 2 of the
	8	License, or (at your option) any later version.
	9
	10	The GNU C Library is distributed in the hope that it will be useful,
	11	but WITHOUT ANY WARRANTY; without even the implied warranty of
	12	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
	13	Library General Public License for more details.
	14
	15	You should have received a copy of the GNU Library General Public
	16	License along with the GNU C Library; see the file COPYING.LIB. If
	17	not, write to the Free Software Foundation, Inc., 675 Mass Ave,
	18	Cambridge, MA 02139, USA. */
	19
	20	#include <link.h>
	21	#include "dynamic-link.h"
	22	#include <stddef.h>
	23	#include <stdlib.h>
	24	#include <unistd.h>
	25
	26
	27	#ifdef RTLD_START
	28	RTLD_START
	29	#else
	30	#error "sysdeps/MACHINE/dl-machine.h fails to define RTLD_START"
	31	#endif
	32
	33	/* System-specific function to do initial startup for the dynamic linker.
	34	After this, file access calls and getenv must work. This is responsible
	35	for setting _dl_secure if we need to be secure (e.g. setuid),
	36	and for setting _dl_argc and _dl_argv, and then calling _dl_main. */
	37	extern Elf32_Addr _dl_sysdep_start (void **start_argptr,
	38	void (dl_main) (const Elf32_Phdr phdr,
	39	Elf32_Word phent,
	40	Elf32_Addr *user_entry));
	41
	42	int _dl_secure;
	43	int _dl_argc;
	44	char **_dl_argv;
	45
	46	struct r_debug dl_r_debug;
	47
	48	static void dl_main (const Elf32_Phdr *phdr,
	49	Elf32_Word phent,
	50	Elf32_Addr *user_entry);
	51
	52	Elf32_Addr
	53	_dl_start (void *arg)
	54	{
421f82e5	55	struct link_map rtld_map;
d66e34cd RM	56
d66e34cd RM	57	/* Figure out the run-time load address of the dynamic linker itself. */
421f82e5	58	rtld_map.l_addr = elf_machine_load_address ();
d66e34cd RM	59
	60	/* Read our own dynamic section and fill in the info array.
	61	Conveniently, the first element of the GOT contains the
	62	offset of _DYNAMIC relative to the run-time load address. */
421f82e5 RM	63	rtld_map.l_ld = (void ) rtld_map.l_addr + elf_machine_got ();
421f82e5 RM	64	elf_get_dynamic_info (rtld_map.l_ld, rtld_map.l_info);
d66e34cd RM	65
d66e34cd RM	66	#ifdef ELF_MACHINE_BEFORE_RTLD_RELOC
421f82e5	67	ELF_MACHINE_BEFORE_RTLD_RELOC (rtld_map.l_info);
d66e34cd RM	68	#endif
	69
	70	/* Relocate ourselves so we can do normal function calls and
	71	data access using the global offset table. */
421f82e5	72
ded29119 RM	73	/* We must initialize `l_type' to make sure it is not `lt_interpreter'.
	74	That is the type to describe us, but not during bootstrapping--it
	75	indicates to elf_machine_rel{,a} that we were already relocated during
	76	bootstrapping, so it must anti-perform each bootstrapping relocation
	77	before applying the final relocation when ld.so is linked in as
	78	normal a shared library. */
	79	rtld_map.l_type = lt_library;
421f82e5 RM	80	ELF_DYNAMIC_RELOCATE (&rtld_map, 0, NULL);
421f82e5 RM	81
d66e34cd RM	82
	83	/* Now life is sane; we can call functions and access global data.
	84	Set up to use the operating system facilities, and find out from
	85	the operating system's program loader where to find the program
	86	header table in core. */
	87
421f82e5	88	dl_r_debug.r_ldbase = rtld_map.l_addr; /* Record our load address. */
d66e34cd RM	89
	90	/* Call the OS-dependent function to set up life so we can do things like
	91	file access. It will call `dl_main' (below) to do all the real work
	92	of the dynamic linker, and then unwind our frame and run the user
	93	entry point on the same stack we entered on. */
	94	return _dl_sysdep_start (&arg, &dl_main);
	95	}
	96
	97
	98	/* Now life is peachy; we can do all normal operations.
	99	On to the real work. */
	100
	101	void _start (void);
	102
a1a9d215 RM	103	static int rtld_command; /* Nonzero if we were run directly. */
a1a9d215 RM	104
d66e34cd RM	105	static void
	106	dl_main (const Elf32_Phdr *phdr,
	107	Elf32_Word phent,
	108	Elf32_Addr *user_entry)
	109	{
	110	void doit (void)
	111	{
421f82e5 RM	112	const Elf32_Phdr *ph;
	113	struct link_map *l;
	114	const char *interpreter_name;
	115	int lazy;
d66e34cd	116
421f82e5 RM	117	if (*user_entry == (Elf32_Addr) &_start)
	118	{
	119	/* Ho ho. We are not the program interpreter! We are the program
	120	itself! This means someone ran ld.so as a command. Well, that
	121	might be convenient to do sometimes. We support it by
	122	interpreting the args like this:
	123
	124	ld.so PROGRAM ARGS...
	125
	126	The first argument is the name of a file containing an ELF
	127	executable we will load and run with the following arguments.
	128	To simplify life here, PROGRAM is searched for using the
	129	normal rules for shared objects, rather than $PATH or anything
	130	like that. We just load it and use its entry point; we don't
	131	pay attention to its PT_INTERP command (we are the interpreter
	132	ourselves). This is an easy way to test a new ld.so before
	133	installing it. */
	134	if (_dl_argc < 2)
	135	_dl_sysdep_fatal ("\
d66e34cd RM	136	Usage: ld.so EXECUTABLE-FILE [ARGS-FOR-PROGRAM...]\n\
	137	You have invoked `ld.so', the helper program for shared library executables.\n\
	138	This program usually lives in the file `/lib/ld.so', and special directives\n\
	139	in executable files using ELF shared libraries tell the system's program\n\
	140	loader to load the helper program from this file. This helper program loads\n\
	141	the shared libraries needed by the program executable, prepares the program\n\
	142	to run, and runs it. You may invoke this helper program directly from the\n\
	143	command line to load and run an ELF executable file; this is like executing\n\
	144	that file itself, but always uses this helper program from the file you\n\
	145	specified, instead of the helper program file specified in the executable\n\
	146	file you run. This is mostly of use for maintainers to test new versions\n\
5bf62f2d RM	147	of this helper program; chances are you did not intend to run this program.\n",
5bf62f2d RM	148	NULL);
421f82e5	149
a1a9d215	150	rtld_command = 1;
421f82e5 RM	151	interpreter_name = _dl_argv[0];
	152	--_dl_argc;
	153	++_dl_argv;
	154	l = _dl_map_object (NULL, _dl_argv[0], user_entry);
	155	phdr = l->l_phdr;
	156	phent = l->l_phnum;
	157	l->l_type = lt_executable;
	158	l->l_libname = (char *) "";
	159	}
	160	else
	161	{
	162	/* Create a link_map for the executable itself.
	163	This will be what dlopen on "" returns. */
	164	l = _dl_new_object ((char *) "", "", lt_executable);
	165	l->l_phdr = phdr;
	166	l->l_phnum = phent;
	167	interpreter_name = 0;
	168	}
d66e34cd	169
421f82e5 RM	170	/* Scan the program header table for the dynamic section. */
	171	for (ph = phdr; ph < &phdr[phent]; ++ph)
	172	switch (ph->p_type)
	173	{
	174	case PT_DYNAMIC:
	175	/* This tells us where to find the dynamic section,
	176	which tells us everything we need to do. */
a1a9d215	177	l->l_ld = (void *) l->l_addr + ph->p_vaddr;
421f82e5 RM	178	break;
	179	case PT_INTERP:
	180	/* This "interpreter segment" was used by the program loader to
	181	find the program interpreter, which is this program itself, the
	182	dynamic linker. We note what name finds us, so that a future
	183	dlopen call or DT_NEEDED entry, for something that wants to link
	184	against the dynamic linker as a shared library, will know that
	185	the shared object is already loaded. */
a1a9d215	186	interpreter_name = (void *) l->l_addr + ph->p_vaddr;
421f82e5 RM	187	break;
	188	}
	189	assert (interpreter_name); /* How else did we get here? */
	190
	191	/* Extract the contents of the dynamic section for easy access. */
	192	elf_get_dynamic_info (l->l_ld, l->l_info);
	193	/* Set up our cache of pointers into the hash table. */
	194	_dl_setup_hash (l);
	195
	196	if (l->l_info[DT_DEBUG])
	197	/* There is a DT_DEBUG entry in the dynamic section. Fill it in
	198	with the run-time address of the r_debug structure, which we
	199	will set up later to communicate with the debugger. */
	200	l->l_info[DT_DEBUG]->d_un.d_ptr = (Elf32_Addr) &dl_r_debug;
	201
	202	l = _dl_new_object ((char *) interpreter_name, interpreter_name,
	203	lt_interpreter);
	204
	205	/* Now process all the DT_NEEDED entries and map in the objects.
	206	Each new link_map will go on the end of the chain, so we will
	207	come across it later in the loop to map in its dependencies. */
	208	for (l = _dl_loaded; l; l = l->l_next)
d66e34cd	209	{
421f82e5 RM	210	if (l->l_info[DT_NEEDED])
	211	{
	212	const char *strtab
	213	= (void *) l->l_addr + l->l_info[DT_STRTAB]->d_un.d_ptr;
	214	const Elf32_Dyn *d;
	215	for (d = l->l_ld; d->d_tag != DT_NULL; ++d)
	216	if (d->d_tag == DT_NEEDED)
	217	_dl_map_object (l, strtab + d->d_un.d_val, NULL);
	218	}
	219	l->l_deps_loaded = 1;
d66e34cd	220	}
d66e34cd	221
421f82e5 RM	222	l = _dl_loaded->l_next;
	223	assert (l->l_type == lt_interpreter);
	224	if (l->l_opencount == 0)
	225	{
	226	/* No DT_NEEDED entry referred to the interpreter object itself.
	227	Remove it from the maps we will use for symbol resolution. */
	228	l->l_prev->l_next = l->l_next;
	229	if (l->l_next)
	230	l->l_next->l_prev = l->l_prev;
	231	}
d66e34cd	232
a1a9d215	233	lazy = !_dl_secure && *(getenv ("LD_BIND_NOW") ?: "") == '\0';
d66e34cd	234
421f82e5 RM	235	/* Now we have all the objects loaded. Relocate them all.
	236	We do this in reverse order so that copy relocs of earlier
	237	objects overwrite the data written by later objects. */
	238	l = _dl_loaded;
	239	while (l->l_next)
	240	l = l->l_next;
	241	do
	242	{
	243	_dl_relocate_object (l, lazy);
	244	l = l->l_prev;
	245	} while (l);
	246
	247	/* Tell the debugger where to find the map of loaded objects. */
	248	dl_r_debug.r_version = 1 /* R_DEBUG_VERSION XXX */;
	249	dl_r_debug.r_map = _dl_loaded;
	250	dl_r_debug.r_brk = (Elf32_Addr) &_dl_r_debug_state;
	251	}
d66e34cd	252	const char *errstring;
421f82e5	253	const char *errobj;
d66e34cd RM	254	int err;
d66e34cd RM	255
421f82e5	256	err = _dl_catch_error (&errstring, &errobj, &doit);
d66e34cd RM	257	if (errstring)
	258	_dl_sysdep_fatal (_dl_argv[0] ?: "<program name unknown>",
	259	": error in loading shared libraries\n",
421f82e5	260	errobj ?: "", errobj ? ": " : "",
d66e34cd RM	261	errstring, err ? ": " : NULL,
	262	err ? strerror (err) : NULL, NULL);
	263
	264	/* Once we return, _dl_sysdep_start will invoke
	265	the DT_INIT functions and then USER_ENTRY. /
	266	}
	267
	268	/* This function exists solely to have a breakpoint set on it by the
	269	debugger. */
	270	void
	271	_dl_r_debug_state (void)
	272	{
	273	}
273d56ce RM	274	\f
	275	#ifndef NDEBUG
	276
	277	/* Define (weakly) our own assert failure function which doesn't use stdio.
	278	If we are linked into the user program (-ldl), the normal __assert_fail
	279	defn can override this one. */
	280
	281	#include "../stdio/_itoa.h"
	282
	283	void
	284	__assert_fail (const char *assertion,
	285	const char file, unsigned int line, const char function)
	286	{
	287	char buf[64];
	288	buf[sizeof buf - 1] = '\0';
	289	_dl_sysdep_fatal ("BUG IN DYNAMIC LINKER ld.so: ",
	290	file, ": ", _itoa (line, buf + sizeof buf - 1, 10, 0),
	291	": ", function ?: "", function ? ": " : "",
5bf62f2d RM	292	"Assertion `", assertion, "' failed!\n",
5bf62f2d RM	293	NULL);
273d56ce RM	294
	295	}
	296	weak_symbol (__assert_fail)
	297
5bf62f2d RM	298	void
	299	__assert_perror_fail (int errnum,
	300	const char *file, unsigned int line,
	301	const char *function)
	302	{
	303	char buf[64];
	304	buf[sizeof buf - 1] = '\0';
	305	_dl_sysdep_fatal ("BUG IN DYNAMIC LINKER ld.so: ",
	306	file, ": ", _itoa (line, buf + sizeof buf - 1, 10, 0),
	307	": ", function ?: "", function ? ": " : "",
	308	"Unexpected error: ", strerror (errnum), "\n", NULL);
	309
	310	}
	311	weak_symbol (__assert_perror_fail)
	312
273d56ce	313	#endif