Reduce the statically linked startup code [BZ #23323]

It turns out the startup code in csu/elf-init.c has a perfect pair of
ROP gadgets (see Marco-Gisbert and Ripoll-Ripoll, "return-to-csu: A
New Method to Bypass 64-bit Linux ASLR").  These functions are not
needed in dynamically-linked binaries because DT_INIT/DT_INIT_ARRAY
are already processed by the dynamic linker.  However, the dynamic
linker skipped the main program for some reason.  For maximum
backwards compatibility, this is not changed, and instead, the main
map is consulted from __libc_start_main if the init function argument
is a NULL pointer.

For statically linked binaries, the old approach based on linker
symbols is still used because there is nothing else available.

A new symbol version __libc_start_main@@GLIBC_2.34 is introduced because
new binaries running on an old libc would not run their ELF
constructors, leading to difficult-to-debug issues.

csu/Makefile

@@ -27,10 +27,9 @@ subdir := csu
 include ../Makeconfig
 
 routines = init-first libc-start $(libc-init) sysdep version check_fds \
-	   libc-tls elf-init dso_handle
+	   libc-tls dso_handle
 aux	 = errno
 elide-routines.os = libc-tls
-static-only-routines = elf-init
 csu-dummies = $(filter-out $(start-installed-name),crt1.o Mcrt1.o)
 extra-objs = start.o \
 	     $(start-installed-name) g$(start-installed-name) $(csu-dummies) \
@@ -59,13 +58,6 @@ CFLAGS-.os += $(no-stack-protector)
 # but it does not matter for this source file.
 CFLAGS-static-reloc.os += $(stack-protector)
 
-# This file is not actually part of the startup code in the nonshared
-# case and statically linked into applications.  See
-# <https://sourceware.org/bugzilla/show_bug.cgi?id=23323>,
-# <https://sourceware.org/ml/libc-alpha/2018-06/msg00717.html>.
-# Also see the note above regarding STACK_PROTECTOR_LEVEL.
-CFLAGS-elf-init.oS += $(stack-protector)
-
 ifeq (yes,$(build-shared))
 extra-objs += S$(start-installed-name) gmon-start.os
 ifneq ($(start-installed-name),$(static-start-installed-name))

csu/Versions

@@ -7,6 +7,9 @@ libc {
     # New special glibc functions.
     gnu_get_libc_release; gnu_get_libc_version;
   }
+  GLIBC_2.34 {
+    __libc_start_main;
+  }
   GLIBC_PRIVATE {
     errno;
   }

csu/elf-init.c

@@ -1,107 +0,0 @@
-/* Startup support for ELF initializers/finalizers in the main executable.
-   Copyright (C) 2002-2021 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.
-
-   In addition to the permissions in the GNU Lesser General Public
-   License, the Free Software Foundation gives you unlimited
-   permission to link the compiled version of this file with other
-   programs, and to distribute those programs without any restriction
-   coming from the use of this file. (The GNU Lesser General Public
-   License restrictions do apply in other respects; for example, they
-   cover modification of the file, and distribution when not linked
-   into another program.)
-
-   Note that people who make modified versions of this file are not
-   obligated to grant this special exception for their modified
-   versions; it is their choice whether to do so. The GNU Lesser
-   General Public License gives permission to release a modified
-   version without this exception; this exception also makes it
-   possible to release a modified version which carries forward this
-   exception.
-
-   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
-   <https://www.gnu.org/licenses/>.  */
-
-#include <stddef.h>
-#include <elf-initfini.h>
-
-
-/* These magic symbols are provided by the linker.  */
-extern void (*__preinit_array_start []) (int, char **, char **)
-  attribute_hidden;
-extern void (*__preinit_array_end []) (int, char **, char **)
-  attribute_hidden;
-extern void (*__init_array_start []) (int, char **, char **)
-  attribute_hidden;
-extern void (*__init_array_end []) (int, char **, char **)
-  attribute_hidden;
-extern void (*__fini_array_start []) (void) attribute_hidden;
-extern void (*__fini_array_end []) (void) attribute_hidden;
-
-
-#if ELF_INITFINI
-/* These function symbols are provided for the .init/.fini section entry
-   points automagically by the linker.  */
-extern void _init (void);
-extern void _fini (void);
-#endif
-
-
-/* These functions are passed to __libc_start_main by the startup code.
-   These get statically linked into each program.  For dynamically linked
-   programs, this module will come from libc_nonshared.a and differs from
-   the libc.a module in that it doesn't call the preinit array.  */
-
-
-void
-__libc_csu_init (int argc, char **argv, char **envp)
-{
-  /* For dynamically linked executables the preinit array is executed by
-     the dynamic linker (before initializing any shared object).  */
-
-#ifndef LIBC_NONSHARED
-  /* For static executables, preinit happens right before init.  */
-  {
-    const size_t size = __preinit_array_end - __preinit_array_start;
-    size_t i;
-    for (i = 0; i < size; i++)
-      (*__preinit_array_start [i]) (argc, argv, envp);
-  }
-#endif
-
-#if ELF_INITFINI
-  _init ();
-#endif
-
-  const size_t size = __init_array_end - __init_array_start;
-  for (size_t i = 0; i < size; i++)
-      (*__init_array_start [i]) (argc, argv, envp);
-}
-
-/* This function should not be used anymore.  We run the executable's
-   destructor now just like any other.  We cannot remove the function,
-   though.  */
-void
-__libc_csu_fini (void)
-{
-#ifndef LIBC_NONSHARED
-  size_t i = __fini_array_end - __fini_array_start;
-  while (i-- > 0)
-    (*__fini_array_start [i]) ();
-
-# if ELF_INITFINI
-  _fini ();
-# endif
-#endif
-}

csu/libc-start.c

@@ -1,4 +1,5 @@
-/* Copyright (C) 1998-2021 Free Software Foundation, Inc.
+/* Perform initialization and invoke main.
+   Copyright (C) 1998-2021 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
@@ -15,10 +16,15 @@
    License along with the GNU C Library; if not, see
    <https://www.gnu.org/licenses/>.  */
 
+/* Note: This code is only part of the startup code proper for
+   statically linked binaries.  For dynamically linked binaries, it
+   resides in libc.so.  */
+
 /* Mark symbols hidden in static PIE for early self relocation to work.  */
 #if BUILD_PIE_DEFAULT
 # pragma GCC visibility push(hidden)
 #endif
+
 #include <assert.h>
 #include <stdlib.h>
 #include <stdio.h>
@@ -29,6 +35,8 @@
 #include <libc-internal.h>
 #include <elf/libc-early-init.h>
 #include <stdbool.h>
+#include <elf-initfini.h>
+#include <shlib-compat.h>
 
 #include <elf/dl-tunables.h>
 
@@ -95,9 +103,11 @@ apply_irel (void)
 # else
 #  define STATIC static inline __attribute__ ((always_inline))
 # endif
+# define DO_DEFINE_LIBC_START_MAIN_VERSION 0
 #else
 # define STATIC
-# define LIBC_START_MAIN __libc_start_main
+# define LIBC_START_MAIN __libc_start_main_impl
+# define DO_DEFINE_LIBC_START_MAIN_VERSION 1
 #endif
 
 #ifdef MAIN_AUXVEC_ARG
@@ -113,6 +123,92 @@ apply_irel (void)
 # define ARCH_INIT_CPU_FEATURES()
 #endif
 
+#ifdef SHARED
+/* Initialization for dynamic executables.  Find the main executable
+   link map and run its init functions.  */
+static void
+call_init (int argc, char **argv, char **env)
+{
+  /* Obtain the main map of the executable.  */
+  struct link_map *l = GL(dl_ns)[LM_ID_BASE]._ns_loaded;
+
+  /* DT_PREINIT_ARRAY is not processed here.  It is already handled in
+     _dl_init in elf/dl-init.c.  Also see the call_init function in
+     the same file.  */
+
+  if (ELF_INITFINI && l->l_info[DT_INIT] != NULL)
+    DL_CALL_DT_INIT(l, l->l_addr + l->l_info[DT_INIT]->d_un.d_ptr,
+		    argc, argv, env);
+
+  ElfW(Dyn) *init_array = l->l_info[DT_INIT_ARRAY];
+  if (init_array != NULL)
+    {
+      unsigned int jm
+	= l->l_info[DT_INIT_ARRAYSZ]->d_un.d_val / sizeof (ElfW(Addr));
+      ElfW(Addr) *addrs = (void *) (init_array->d_un.d_ptr + l->l_addr);
+      for (unsigned int j = 0; j < jm; ++j)
+	((dl_init_t) addrs[j]) (argc, argv, env);
+    }
+}
+
+#else /* !SHARED */
+
+/* These magic symbols are provided by the linker.  */
+extern void (*__preinit_array_start []) (int, char **, char **)
+  attribute_hidden;
+extern void (*__preinit_array_end []) (int, char **, char **)
+  attribute_hidden;
+extern void (*__init_array_start []) (int, char **, char **)
+  attribute_hidden;
+extern void (*__init_array_end []) (int, char **, char **)
+  attribute_hidden;
+extern void (*__fini_array_start []) (void) attribute_hidden;
+extern void (*__fini_array_end []) (void) attribute_hidden;
+
+# if ELF_INITFINI
+/* These function symbols are provided for the .init/.fini section entry
+   points automagically by the linker.  */
+extern void _init (void);
+extern void _fini (void);
+# endif
+
+/* Initialization for static executables.  There is no dynamic
+   segment, so we access the symbols directly.  */
+static void
+call_init (int argc, char **argv, char **envp)
+{
+  /* For static executables, preinit happens right before init.  */
+  {
+    const size_t size = __preinit_array_end - __preinit_array_start;
+    size_t i;
+    for (i = 0; i < size; i++)
+      (*__preinit_array_start [i]) (argc, argv, envp);
+  }
+
+# if ELF_INITFINI
+  _init ();
+# endif
+
+  const size_t size = __init_array_end - __init_array_start;
+  for (size_t i = 0; i < size; i++)
+      (*__init_array_start [i]) (argc, argv, envp);
+}
+
+/* Likewise for the destructor.  */
+static void
+call_fini (void *unused)
+{
+  size_t i = __fini_array_end - __fini_array_start;
+  while (i-- > 0)
+    (*__fini_array_start [i]) ();
+
+# if ELF_INITFINI
+  _fini ();
+# endif
+}
+
+#endif /* !SHARED */
+
 #include <libc-start.h>
 
 STATIC int LIBC_START_MAIN (int (*main) (int, char **, char **
@@ -129,9 +225,16 @@ STATIC int LIBC_START_MAIN (int (*main) (int, char **, char **
      __attribute__ ((noreturn));
 
 
-/* Note: the fini parameter is ignored here for shared library.  It
+/* Note: The init and fini parameters are no longer used.  fini is
-   is registered with __cxa_atexit.  This had the disadvantage that
+   completely unused, init is still called if not NULL, but the
-   finalizers were called in more than one place.  */
+   current startup code always passes NULL.  (In the future, it would
+   be possible to use fini to pass a version code if init is NULL, to
+   indicate the link-time glibc without introducing a hard
+   incompatibility for new programs with older glibc versions.)
+
+   For dynamically linked executables, the dynamic segment is used to
+   locate constructors and destructors.  For statically linked
+   executables, the relevant symbols are access directly.  */
 STATIC int
 LIBC_START_MAIN (int (*main) (int, char **, char ** MAIN_AUXVEC_DECL),
 		 int argc, char **argv,
@@ -258,9 +361,8 @@ LIBC_START_MAIN (int (*main) (int, char **, char ** MAIN_AUXVEC_DECL),
      run the constructors in `_dl_start_user'.  */
   __libc_init_first (argc, argv, __environ);
 
-  /* Register the destructor of the program, if any.  */
+  /* Register the destructor of the statically-linked program.  */
-  if (fini)
+  __cxa_atexit (call_fini, NULL, NULL);
-    __cxa_atexit ((void (*) (void *)) fini, NULL, NULL);
 
   /* Some security at this point.  Prevent starting a SUID binary where
      the standard file descriptors are not opened.  We have to do this
@@ -268,15 +370,24 @@ LIBC_START_MAIN (int (*main) (int, char **, char ** MAIN_AUXVEC_DECL),
      loader did the work already.  */
   if (__builtin_expect (__libc_enable_secure, 0))
     __libc_check_standard_fds ();
-#endif
+#endif /* !SHARED */
 
   /* Call the initializer of the program, if any.  */
 #ifdef SHARED
   if (__builtin_expect (GLRO(dl_debug_mask) & DL_DEBUG_IMPCALLS, 0))
     GLRO(dl_debug_printf) ("\ninitialize program: %s\n\n", argv[0]);
-#endif
+
-  if (init)
+  if (init != NULL)
+    /* This is a legacy program which supplied its own init
+       routine.  */
     (*init) (argc, argv, __environ MAIN_AUXVEC_PARAM);
+  else
+    /* This is a current program.  Use the dynamic segment to find
+       constructors.  */
+    call_init (argc, argv, __environ);
+#else /* !SHARED */
+  call_init (argc, argv, __environ);
+#endif /* SHARED */
 
 #ifdef SHARED
   /* Auditing checkpoint: we have a new object.  */
@@ -365,3 +476,36 @@ LIBC_START_MAIN (int (*main) (int, char **, char ** MAIN_AUXVEC_DECL),
 
   exit (result);
 }
+
+/* Starting with glibc 2.34, the init parameter is always NULL.  Older
+   libcs are not prepared to handle that.  The macro
+   DEFINE_LIBC_START_MAIN_VERSION creates GLIBC_2.34 alias, so that
+   newly linked binaries reflect that dependency.  The macros below
+   expect that the exported function is called
+   __libc_start_main_impl.  */
+#ifdef SHARED
+# define DEFINE_LIBC_START_MAIN_VERSION \
+  DEFINE_LIBC_START_MAIN_VERSION_1 \
+  strong_alias (__libc_start_main_impl, __libc_start_main_alias_2)	\
+  versioned_symbol (libc, __libc_start_main_alias_2, __libc_start_main, \
+		    GLIBC_2_34);
+
+# if SHLIB_COMPAT(libc, GLIBC_2_0, GLIBC_2_34)
+#  define DEFINE_LIBC_START_MAIN_VERSION_1 \
+  strong_alias (__libc_start_main_impl, __libc_start_main_alias_1)	\
+  compat_symbol (libc, __libc_start_main_alias_1, __libc_start_main, GLIBC_2_0);
+#  else
+#  define DEFINE_LIBC_START_MAIN_VERSION_1
+# endif
+#else  /* !SHARED */
+/* Enable calling the function under its exported name.  */
+# define DEFINE_LIBC_START_MAIN_VERSION \
+  strong_alias (__libc_start_main_impl, __libc_start_main)
+#endif
+
+/* Only define the version information if LIBC_START_MAIN was not set.
+   If there is a wrapper file, it must expand
+   DEFINE_LIBC_START_MAIN_VERSION on its own.  */
+#if DO_DEFINE_LIBC_START_MAIN_VERSION
+DEFINE_LIBC_START_MAIN_VERSION
+#endif

elf/dl-init.c

@@ -22,10 +22,6 @@
 #include <elf-initfini.h>
 
 
-/* Type of the initializer.  */
-typedef void (*init_t) (int, char **, char **);
-
-
 static void
 call_init (struct link_map *l, int argc, char **argv, char **env)
 {
@@ -71,7 +67,7 @@ call_init (struct link_map *l, int argc, char **argv, char **env)
 
       addrs = (ElfW(Addr) *) (init_array->d_un.d_ptr + l->l_addr);
       for (j = 0; j < jm; ++j)
-	((init_t) addrs[j]) (argc, argv, env);
+	((dl_init_t) addrs[j]) (argc, argv, env);
     }
 }
 
@@ -103,7 +99,7 @@ _dl_init (struct link_map *main_map, int argc, char **argv, char **env)
 
       addrs = (ElfW(Addr) *) (preinit_array->d_un.d_ptr + main_map->l_addr);
       for (cnt = 0; cnt < i; ++cnt)
-	((init_t) addrs[cnt]) (argc, argv, env);
+	((dl_init_t) addrs[cnt]) (argc, argv, env);
     }
 
   /* Stupid users forced the ELF specification to be changed.  It now

sysdeps/aarch64/start.S

@@ -63,26 +63,16 @@ ENTRY(_start)
 # ifdef SHARED
         adrp    x0, :got:main
 	ldr     PTR_REG (0), [x0, #:got_lo12:main]
-
-        adrp    x3, :got:__libc_csu_init
-	ldr     PTR_REG (3), [x3, #:got_lo12:__libc_csu_init]
-
-        adrp    x4, :got:__libc_csu_fini
-	ldr     PTR_REG (4), [x4, #:got_lo12:__libc_csu_fini]
 # else
 	adrp	x0, __wrap_main
 	add	x0, x0, :lo12:__wrap_main
-	adrp	x3, __libc_csu_init
-	add	x3, x3, :lo12:__libc_csu_init
-	adrp	x4, __libc_csu_fini
-	add	x4, x4, :lo12:__libc_csu_fini
 # endif
 #else
 	/* Set up the other arguments in registers */
 	MOVL (0, main)
-	MOVL (3, __libc_csu_init)
-	MOVL (4, __libc_csu_fini)
 #endif
+	mov	x3, #0		/* Used to be init.  */
+	mov	x4, #0		/* Used to be fini.  */
 
 	/* __libc_start_main (main, argc, argv, init, fini, rtld_fini,
 			      stack_end) */

sysdeps/alpha/start.S

@@ -55,9 +55,8 @@ _start:
 	ldl	a1, 16(sp)	/* get argc */
 	lda	a2, 24(sp)	/* get argv */
 
-  /* Load address of our own entry points to .fini and .init.  */
+	mov	$r31, a3 	/* Used to be init.  */
-	lda	a3, __libc_csu_init
+	mov	$r31, a4 	/* Used to be fini.  */
-	lda	a4, __libc_csu_fini
 
   /* Store address of the shared library termination function.  */
 	mov	v0, a5

sysdeps/arc/start.S

@@ -49,15 +49,14 @@ ENTRY (ENTRY_POINT)
 
 	/* __libc_start_main (main, argc, argv, init, fini, rtld_fini, stack_end).  */
 
+	mov_s	r3, 0 		/* Used to be init.  */
+	mov	r4, 0		/* Used to be fini.  */
+
 #ifdef SHARED
 	ld	r0, [pcl, @main@gotpc]
-	ld	r3, [pcl, @__libc_csu_init@gotpc]
-	ld	r4, [pcl, @__libc_csu_fini@gotpc]
 	bl	__libc_start_main@plt
 #else
 	mov_s	r0, main
-	mov_s	r3, __libc_csu_init
-	mov	r4, __libc_csu_fini
 	bl	__libc_start_main
 #endif
 

sysdeps/arm/start.S

@@ -94,30 +94,20 @@ _start:
 	adr a4, .L_GOT
 	add sl, sl, a4
 
-	ldr ip, .L_GOT+4	/* __libc_csu_fini */
+	mov a4, #0		/* Used to be init.  */
-	ldr ip, [sl, ip]
+	push { a4 }		/* Used to be fini.  */
 
-	push { ip }		/* Push __libc_csu_fini */
+	ldr a1, .L_GOT+4	/* main */
-
-	ldr a4, .L_GOT+8	/* __libc_csu_init */
-	ldr a4, [sl, a4]
-
-	ldr a1, .L_GOT+12	/* main */
 	ldr a1, [sl, a1]
 
 	/* __libc_start_main (main, argc, argv, init, fini, rtld_fini, stack_end) */
 	/* Let the libc call main and exit with its return code.  */
 	bl __libc_start_main(PLT)
 #else
-	/* Fetch address of __libc_csu_fini */
-	ldr ip, =__libc_csu_fini
 
-	/* Push __libc_csu_fini */
+	mov a4, #0		/* Used to init.  */
-	push { ip }
+	push { a4 }		/* Used to fini.  */
-
-	/* Set up the other arguments in registers */
 	ldr a1, =main
-	ldr a4, =__libc_csu_init
 
 	/* __libc_start_main (main, argc, argv, init, fini, rtld_fini, stack_end) */
 	/* Let the libc call main and exit with its return code.  */
@@ -131,8 +121,6 @@ _start:
 	.align 2
 .L_GOT:
 	.word _GLOBAL_OFFSET_TABLE_ - .L_GOT
-	.word __libc_csu_fini(GOT)
-	.word __libc_csu_init(GOT)
 	.word main(GOT)
 #endif
 

sysdeps/csky/abiv2/start.S

@@ -66,13 +66,9 @@ _start:
 .Lgetpc:
 	lrw	gb, .Lgetpc@GOTPC
 	addu	gb, t0
-	lrw	a3, __libc_csu_fini@GOT
-	ldr.w	a3, (gb, a3 << 0)
-	stw	a3, (sp, 0)
 
-	lrw	a3, __libc_csu_init@GOT
+	movi	a3, 0		/* Used to be init.  */
-	addu	a3, gb
+	stw 	a3, (sp, 0) 	/* Used to be fini.  */
-	ldw	a3, (a3, 0)
 
 	lrw	t0, main@GOT
 	addu	t0, gb
@@ -85,14 +81,9 @@ _start:
 	ldr.w	t1, (gb, t1 << 0)
 	jsr	t1
 #else
-	/* Fetch address of __libc_csu_fini.  */
+	movi	a3, 0		/* Used to be init.  */
-	lrw	a0, __libc_csu_fini
+	stw 	a3, (sp, 0) 	/* Used to be fini.  */
-	/* Push __libc_csu_fini */
-	stw	a0, (sp, 0)
-
-	/* Set up the other arguments in registers.  */
 	lrw	a0, main
-	lrw	a3, __libc_csu_init
 	/* Let the libc call main and exit with its return code.  */
 	jsri	__libc_start_main
 

sysdeps/generic/ldsodefs.h

@@ -93,6 +93,10 @@ typedef struct link_map *lookup_t;
    : (__glibc_unlikely ((ref)->st_shndx == SHN_ABS) ? 0			\
       : LOOKUP_VALUE_ADDRESS (map, map_set)) + (ref)->st_value)
 
+/* Type of a constructor function, in DT_INIT, DT_INIT_ARRAY,
+   DT_PREINIT_ARRAY.  */
+typedef void (*dl_init_t) (int, char **, char **);
+
 /* On some architectures a pointer to a function is not just a pointer
    to the actual code of the function but rather an architecture
    specific descriptor. */
@@ -101,7 +105,7 @@ typedef struct link_map *lookup_t;
  (void *) SYMBOL_ADDRESS (map, ref, false)
 # define DL_LOOKUP_ADDRESS(addr) ((ElfW(Addr)) (addr))
 # define DL_CALL_DT_INIT(map, start, argc, argv, env) \
- ((init_t) (start)) (argc, argv, env)
+ ((dl_init_t) (start)) (argc, argv, env)
 # define DL_CALL_DT_FINI(map, start) ((fini_t) (start)) ()
 #endif
 

sysdeps/hppa/dl-lookupcfg.h

@@ -56,7 +56,7 @@ void attribute_hidden _dl_unmap (struct link_map *map);
 {							\
   ElfW(Addr) addr;					\
   DL_DT_FUNCTION_ADDRESS(map, start, , addr)		\
-  init_t init = (init_t) addr; 				\
+  dl_init_t init = (dl_init_t) addr; 			\
   init (argc, argv, env);				\
 }
 

sysdeps/hppa/start.S

@@ -36,8 +36,6 @@
 	.import main, code
 	.import $global$, data
 	.import __libc_start_main, code
-	.import __libc_csu_fini, code
-	.import __libc_csu_init, code
 
 	/* Have the linker create plabel words so we get PLABEL32
 	   relocs and not 21/14.  The use of 21/14 relocs is only
@@ -52,10 +50,6 @@
 	.word P%main
 .Lp__libc_start_main:
 	.word P%__libc_start_main
-.Lp__libc_csu_fini:
-	.word P%__libc_csu_fini
-.Lp__libc_csu_init:
-	.word P%__libc_csu_init
 
 	.text
 	.align 4
@@ -77,8 +71,8 @@ _start:
 		1. r26 - Application main
 		2. r25 - argc
 		3. r24 - argv
-		4. r23 - __libc_csu_init
+		4. r23 - init (unused)
-		5. sp-52 - __libc_csu_fini
+		5. sp-52 - fini (unused)
 		6. sp-56 - rtld_fini
 		7. sp-60 - stackend  */
 
@@ -108,14 +102,6 @@ _start:
 	addil	LT'.Lpmain, %r19
 	ldw	RT'.Lpmain(%r1), %r26
 	ldw	0(%r26),%r26
-	/* void (*init) (void) (4th argument) */
-	addil	LT'.Lp__libc_csu_init, %r19
-	ldw	RT'.Lp__libc_csu_init(%r1), %r23
-	ldw	0(%r23), %r23
-	/* void (*fini) (void) (5th argument) */
-	addil	LT'.Lp__libc_csu_fini, %r19
-	ldw	RT'.Lp__libc_csu_fini(%r1), %r22
-	ldw	0(%r22), %r22
 #else
 	/* Load $global$ address into %dp */
 	ldil	L%$global$, %dp
@@ -124,13 +110,9 @@ _start:
 	/* load main (1st argument) */
 	ldil	LR'.Lpmain, %r26
 	ldw	RR'.Lpmain(%r26), %r26
-	/* void (*init) (void) (4th argument) */
-	ldil	LR'.Lp__libc_csu_init, %r23
-	ldw	RR'.Lp__libc_csu_init(%r23), %r23
-	/* void (*fini) (void) (5th argument) */
-	ldil	LR'.Lp__libc_csu_fini, %r22
-	ldw	RR'.Lp__libc_csu_fini(%r22), %r22
 #endif
+	ldi	0,%r23		/* Used to be init.  */
+	ldi	0,%r22		/* Used to be fini.  */
 	/* Store 5th argument */
 	stw	%r22, -52(%sp)
 	/* void *stack_end (7th argument) */

sysdeps/i386/start.S

@@ -87,11 +87,9 @@ ENTRY (_start)
 	call 1f
 	addl $_GLOBAL_OFFSET_TABLE_, %ebx
 
-	/* Push address of our own entry points to .fini and .init.  */
+	/* This used to be the addresses of .fini and .init.  */
-	leal __libc_csu_fini@GOTOFF(%ebx), %eax
+	pushl $0
-	pushl %eax
+	pushl $0
-	leal __libc_csu_init@GOTOFF(%ebx), %eax
-	pushl %eax
 
 	pushl %ecx		/* Push second argument: argv.  */
 	pushl %esi		/* Push first argument: argc.  */
@@ -112,9 +110,9 @@ ENTRY (_start)
 	   But let the libc call main.    */
 	call __libc_start_main@PLT
 #else
-	/* Push address of our own entry points to .fini and .init.  */
+	/* This used to be the addresses of .fini and .init.  */
-	pushl $__libc_csu_fini
+	pushl $0
-	pushl $__libc_csu_init
+	pushl $0
 
 	pushl %ecx		/* Push second argument: argv.  */
 	pushl %esi		/* Push first argument: argc.  */

sysdeps/ia64/dl-lookupcfg.h

@@ -50,7 +50,7 @@ extern void attribute_hidden _dl_unmap (struct link_map *map);
 {							\
   ElfW(Addr) addr;					\
   DL_DT_FUNCTION_ADDRESS(map, start, , addr)		\
-  init_t init = (init_t) addr; 				\
+  dl_init_t init = (dl_init_t) addr; 			\
   init (argc, argv, env);				\
 }
 

sysdeps/ia64/start.S

@@ -82,20 +82,15 @@ _start:
 	{
 	  addl r11 = @ltoff(__libc_ia64_register_backing_store_base), gp
 	  addl out0 = @ltoff(@fptr(main)), gp
-	  addl out3 = @ltoff(@fptr(__libc_csu_init)), gp
+	  mov out3 = r0		/* Used to be init.  */
 	  ;;
 	}
 	{ .mmi
 	  ld8 r3 = [r11]	/* pointer to __libc_ia64_register_backing_store_base */
 	  ld8 out0 = [out0]	/* pointer to `main' function descriptor */
-	  addl out4 = @ltoff(@fptr(__libc_csu_fini)), gp
+	  mov out4 = r0		/* Used to be fini.  */
 	  ;;
 	}
-	{ .mmi
-	  ld8 out3 = [out3]	/* pointer to `init' function descriptor */
-	  ld8 out4 = [out4]	/* pointer to `fini' function descriptor */
-	  nop 0
-	}
 	.body
 	{ .mib
 	  st8 [r3] = r10

sysdeps/m68k/start.S

@@ -76,15 +76,14 @@ _start:
 	pea (%a1)		/* Push address of the shared library
 				   termination function.  */
 
+	/* These used to be addresses of the .fini and .init entry points.  */
+	clr.l -(%sp)
+	clr.l -(%sp)
+
 #ifdef PIC
 	/* Load PIC register.  */
 	LOAD_GOT (%a5)
 
-	/* Push the address of our own entry points to `.fini' and
-	   `.init'.  */
-	move.l __libc_csu_fini@GOT(%a5), -(%sp)
-	move.l __libc_csu_init@GOT(%a5), -(%sp)
-
 	pea (%a0)		/* Push second argument: argv.  */
 	move.l %d0, -(%sp)	/* Push first argument: argc.  */
 
@@ -94,10 +93,6 @@ _start:
 	   let the libc call main.  */
 	jbsr __libc_start_main@PLTPC
 #else
-	/* Push the address of our own entry points to `.fini' and
-	   `.init'.  */
-	pea __libc_csu_fini
-	pea __libc_csu_init
 
 	pea (%a0)		/* Push second argument: argv.  */
 	move.l %d0, -(%sp)	/* Push first argument: argc.  */

sysdeps/mach/hurd/i386/libc.abilist

@@ -2203,6 +2203,7 @@ GLIBC_2.33 mknod F
 GLIBC_2.33 mknodat F
 GLIBC_2.33 stat F
 GLIBC_2.33 stat64 F
+GLIBC_2.34 __libc_start_main F
 GLIBC_2.4 __confstr_chk F
 GLIBC_2.4 __fgets_chk F
 GLIBC_2.4 __fgets_unlocked_chk F

sysdeps/microblaze/start.S

@@ -63,14 +63,14 @@ _start:
     mfs     r20,rpc
     addik   r20,r20,_GLOBAL_OFFSET_TABLE_+8
     lwi     r5,r20,main@GOT
-    lwi     r8,r20,__libc_csu_init@GOT
+    addk    r8,r0,r0		/* Used to be init.  */
-    lwi     r9,r20,__libc_csu_fini@GOT
+    addk    r9,r0,r0		/* Used to be fini.  */
     brid    __libc_start_main@PLT
     addk    r10,r0,r0
 #else
     addik   r5,r0,main
-    addik   r8,r0,__libc_csu_init
+    addk    r8,r0,r0		/* Used to be init.  */
-    addik   r9,r0,__libc_csu_fini
+    addk    r9,r0,r0		/* Used to be fini.  */
     brid    __libc_start_main
     addk    r10,r0,r0
 #endif

sysdeps/mips/start.S

@@ -96,13 +96,13 @@ ENTRY_POINT:
 # if _MIPS_SIM == _ABIO32
 	PTR_SUBIU $29, 32
 # endif
-	PTR_LA $7, __libc_csu_init		/* init */
+	move  $7, $0			/* Used to be init.  */
-	PTR_LA $8, __libc_csu_fini
 # if _MIPS_SIM == _ABIO32
-	PTR_S $8, 16($29)		/* fini */
+	PTR_S $0, 16($29)		/* Used to be fini.  */
 	PTR_S $2, 20($29)		/* rtld_fini */
 	PTR_S $29, 24($29)		/* stack_end */
 # else
+	move $8, $0		/* Used to be fini.  */
 	move $9, $2		/* rtld_fini */
 	move $10, $29		/* stack_end */
 # endif
@@ -143,19 +143,17 @@ ENTRY_POINT:
 	/* Lay out last arguments, and call __libc_start_main().  */
 # ifdef __PIC__
 	sw	$7, 24($sp)			/* stack_end */
-	lw	$4, %got(__libc_csu_fini)($3)
+	move	$4, $0				/* Used to be ini.  */
-	lw	$7, %got(__libc_csu_init)($3)	/* init */
+	sw	$0, 16($sp)			/* Used to be fini.  */
-	sw	$4, 16($sp)			/* fini */
 	lw	$4, %got(main)($3)		/* main */
 	lw	$3, %call16(__libc_start_main)($3)
 	sw	$2, 20($sp)			/* rtld_fini */
 	move	$25, $3
 	jalr	$3
 # else
-	lw	$4, 1f
 	sw	$7, 24($sp)			/* stack_end */
-	lw	$7, 2f				/* init */
+	move	$7, $0				/* Used to be init.  */
-	sw	$4, 16($sp)			/* fini */
+	sw	$0, 16($sp)			/* Used to be fini.  */
 	lw	$4, 3f				/* main */
 	sw	$2, 20($sp)			/* rtld_fini */
 	/* Load and call __libc_start_main().  */
@@ -165,8 +163,6 @@ ENTRY_POINT:
 hlt:	b	hlt		/* Crash if somehow it does return.  */
 # ifndef __PIC__
 	.align	2
-1:	.word	__libc_csu_fini
-2:	.word	__libc_csu_init
 3:	.word	main
 4:	.word	__libc_start_main
 # endif

sysdeps/nios2/start.S

@@ -92,18 +92,11 @@ _start:
 	addi	r2, r2, %lo(_gp_got - 1b)
 	add	r22, r22, r2
 
-	/* Push fini */
+	/* Used to be fini.  */
-	movhi	r8, %call_hiadj(__libc_csu_fini)
+	stw	zero, 0(sp)
-	addi	r8, r8, %call_lo(__libc_csu_fini)
-	add	r8, r8, r22
-	ldw	r8, 0(r8)
-	stw	r8, 0(sp)
 
-	/* r7 == init */
+	/* Used to be init.  */
-	movhi	r7, %call_hiadj(__libc_csu_init)
+	mov	r7, zero
-	addi	r7, r7, %call_lo(__libc_csu_init)
-	add	r7, r7, r22
-	ldw	r7, 0(r7)
 
 	/* r6 == argv */
 	addi	r6, sp, 16

sysdeps/powerpc/powerpc32/start.S

@@ -52,8 +52,8 @@
 L(start_addresses):
 	.long	_SDA_BASE_
 	.long	main
-	.long 	__libc_csu_init
+	.long 	0 /* Used to be init.  */
-	.long 	__libc_csu_fini
+	.long 	0 /* Used to be fini.  */
 	ASM_SIZE_DIRECTIVE(L(start_addresses))
 
 	.section ".text"

sysdeps/powerpc/powerpc64/start.S

@@ -53,8 +53,8 @@ L(start_addresses):
 	.quad	0 /* was _SDA_BASE_  but not in 64-bit ABI*/
 /*     function descriptors so don't need JUMPTARGET */
 	.quad	main
-	.quad 	__libc_csu_init
+	.quad 	0 /* Used to be init.  */
-	.quad 	__libc_csu_fini
+	.quad 	0 /* Used to be fini.  */
 
 	ASM_SIZE_DIRECTIVE(L(start_addresses))
 

sysdeps/riscv/start.S

@@ -54,8 +54,8 @@ ENTRY (ENTRY_POINT)
 	REG_L a1, 0(sp)      /* argc.  */
 	addi  a2, sp, SZREG  /* argv.  */
 	andi  sp, sp, ALMASK /* Align stack. */
-	lla   a3, __libc_csu_init
+	li    a3, 0	     /* Used to be init.  */
-	lla   a4, __libc_csu_fini
+	li    a4, 0	     /* Used to be fini.  */
 	mv    a6, sp  /* stack_end.  */
 
 	call  __libc_start_main@plt

sysdeps/s390/s390-32/start.S

@@ -175,18 +175,16 @@ _start:
 	 */
 	stm     %r14,%r15,96(%r15)      # store rtld_fini/stack_end to parameter area
 	la      %r7,96(%r15)
-	l       %r6,.L2-.Llit(%r13)     # load pointer to __libc_csu_fini
-	l       %r5,.L1-.Llit(%r13)     # load pointer to __libc_csu_init
 	l       %r2,.L3-.Llit(%r13)     # load pointer to main
 	l       %r1,.L4-.Llit(%r13)	# load pointer to __libc_start_main
 #ifdef PIC
 	l       %r12,.L5-.Llit(%r13)    # load .got pointer
-	la	%r6,0(%r13,%r6)
-	la	%r5,0(%r13,%r5)
 	la	%r12,0(%r13,%r12)
 	l	%r2,0(%r12,%r2)
 	la	%r1,0(%r13,%r1)
 #endif
+	lhi	%r6, 0			# Used to fini.
+	lhi	%r5, 0			# Used to init.
 
 	/* ok, now branch to the libc main routine */
 	basr    %r14,%r1
@@ -197,13 +195,9 @@ _start:
 	cfi_endproc
 .Llit:
 #ifndef PIC
-.L1:    .long  __libc_csu_init
-.L2:    .long  __libc_csu_fini
 .L3:    .long  main
 .L4:    .long  __libc_start_main
 #else
-.L1:    .long  __libc_csu_init-.Llit
-.L2:    .long  __libc_csu_fini-.Llit
 .L3:    .long  main@GOT
 .L4:    .long  __libc_start_main@plt-.Llit
 .L5:    .long  _GLOBAL_OFFSET_TABLE_-.Llit

sysdeps/s390/s390-64/start.S

@@ -80,8 +80,8 @@ _start:
 	 */
 	stmg	%r14,%r15,160(%r15)	# store rtld_fini/stack_end to parameter area
 	la	%r7,160(%r15)
-	larl	%r6,__libc_csu_fini	# load pointer to __libc_csu_fini
+	lghi	%r6,0			# Used to be fini.
-	larl	%r5,__libc_csu_init	# load pointer to __libc_csu_init
+	lghi	%r5,0			# Used to be init.
 
 	/* Ok, now branch to the libc main routine.  */
 #ifdef PIC

sysdeps/sh/start.S

@@ -70,12 +70,11 @@ _start:
 
 	/* Push the last arguments to main() onto the stack */
 	mov.l r4,@-r15
-	mov.l L_fini,r0
+	mov.l r14,@-r15		/* Used to be fini.  */
-	mov.l r0,@-r15
 
 	/* Set up the other arguments for main() that go in registers */
 	mov.l L_main,r4
-	mov.l L_init,r7
+	mov #0,r7		/* Used to be init.  */
 
 	/* __libc_start_main (main, argc, argv, init, fini, rtld_fini) */
 
@@ -90,10 +89,6 @@ _start:
 	.align	2
 L_main:
 	.long	main
-L_init:
-	.long	__libc_csu_init
-L_fini:
-	.long	__libc_csu_fini
 L_libc_start_main:
 	.long	__libc_start_main
 L_abort:

sysdeps/sparc/sparc32/start.S

@@ -59,22 +59,14 @@ _start:
   /* Load the addresses of the user entry points.  */
 #ifndef PIC
 	sethi	%hi(main), %o0
-	sethi	%hi(__libc_csu_init), %o3
-	sethi	%hi(__libc_csu_fini), %o4
 	or	%o0, %lo(main), %o0
-	or	%o3, %lo(__libc_csu_init), %o3
-	or	%o4, %lo(__libc_csu_fini), %o4
 #else
 	sethi	%gdop_hix22(main), %o0
-	sethi	%gdop_hix22(__libc_csu_init), %o3
-	sethi	%gdop_hix22(__libc_csu_fini), %o4
 	xor	%o0, %gdop_lox10(main), %o0
-	xor	%o3, %gdop_lox10(__libc_csu_init), %o3
-	xor	%o4, %gdop_lox10(__libc_csu_fini), %o4
 	ld	[%l7 + %o0], %o0, %gdop(main)
-	ld	[%l7 + %o3], %o3, %gdop(__libc_csu_init)
-	ld	[%l7 + %o4], %o4, %gdop(__libc_csu_fini)
 #endif
+	mov	0, %o3		/* Used to be init.  */
+	mov	0, %o4		/* Used to be fini.  */
 
   /* When starting a binary via the dynamic linker, %g1 contains the
      address of the shared library termination function, which will be

sysdeps/sparc/sparc64/start.S

@@ -60,22 +60,14 @@ _start:
   /* Load the addresses of the user entry points.  */
 #ifndef PIC
 	sethi	%hi(main), %o0
-	sethi	%hi(__libc_csu_init), %o3
-	sethi	%hi(__libc_csu_fini), %o4
 	or	%o0, %lo(main), %o0
-	or	%o3, %lo(__libc_csu_init), %o3
-	or	%o4, %lo(__libc_csu_fini), %o4
 #else
 	sethi	%gdop_hix22(main), %o0
-	sethi	%gdop_hix22(__libc_csu_init), %o3
-	sethi	%gdop_hix22(__libc_csu_fini), %o4
 	xor	%o0, %gdop_lox10(main), %o0
-	xor	%o3, %gdop_lox10(__libc_csu_init), %o3
-	xor	%o4, %gdop_lox10(__libc_csu_fini), %o4
 	ldx	[%l7 + %o0], %o0, %gdop(main)
-	ldx	[%l7 + %o3], %o3, %gdop(__libc_csu_init)
-	ldx	[%l7 + %o4], %o4, %gdop(__libc_csu_fini)
 #endif
+	mov	0, %o3		/* Used to be init.  */
+	mov	0, %o4		/* Used to be fini.  */
 
   /* When starting a binary via the dynamic linker, %g1 contains the
      address of the shared library termination function, which will be

sysdeps/unix/sysv/linux/aarch64/libc.abilist

@@ -2171,3 +2171,4 @@ GLIBC_2.33 mknod F
 GLIBC_2.33 mknodat F
 GLIBC_2.33 stat F
 GLIBC_2.33 stat64 F
+GLIBC_2.34 __libc_start_main F

sysdeps/unix/sysv/linux/alpha/libc.abilist

@@ -2253,6 +2253,7 @@ GLIBC_2.33 mknod F
 GLIBC_2.33 mknodat F
 GLIBC_2.33 stat F
 GLIBC_2.33 stat64 F
+GLIBC_2.34 __libc_start_main F
 GLIBC_2.4 _IO_fprintf F
 GLIBC_2.4 _IO_printf F
 GLIBC_2.4 _IO_sprintf F

sysdeps/unix/sysv/linux/arc/libc.abilist

@@ -1931,3 +1931,4 @@ GLIBC_2.33 mknod F
 GLIBC_2.33 mknodat F
 GLIBC_2.33 stat F
 GLIBC_2.33 stat64 F
+GLIBC_2.34 __libc_start_main F

sysdeps/unix/sysv/linux/arm/be/libc.abilist

@@ -155,6 +155,7 @@ GLIBC_2.33 mknod F
 GLIBC_2.33 mknodat F
 GLIBC_2.33 stat F
 GLIBC_2.33 stat64 F
+GLIBC_2.34 __libc_start_main F
 GLIBC_2.4 _Exit F
 GLIBC_2.4 _IO_2_1_stderr_ D 0xa0
 GLIBC_2.4 _IO_2_1_stdin_ D 0xa0

sysdeps/unix/sysv/linux/arm/le/libc.abilist

@@ -152,6 +152,7 @@ GLIBC_2.33 mknod F
 GLIBC_2.33 mknodat F
 GLIBC_2.33 stat F
 GLIBC_2.33 stat64 F
+GLIBC_2.34 __libc_start_main F
 GLIBC_2.4 _Exit F
 GLIBC_2.4 _IO_2_1_stderr_ D 0xa0
 GLIBC_2.4 _IO_2_1_stdin_ D 0xa0

sysdeps/unix/sysv/linux/csky/libc.abilist

@@ -2115,3 +2115,4 @@ GLIBC_2.33 mknod F
 GLIBC_2.33 mknodat F
 GLIBC_2.33 stat F
 GLIBC_2.33 stat64 F
+GLIBC_2.34 __libc_start_main F

sysdeps/unix/sysv/linux/hppa/libc.abilist

@@ -2074,6 +2074,7 @@ GLIBC_2.33 mknod F
 GLIBC_2.33 mknodat F
 GLIBC_2.33 stat F
 GLIBC_2.33 stat64 F
+GLIBC_2.34 __libc_start_main F
 GLIBC_2.4 __confstr_chk F
 GLIBC_2.4 __fgets_chk F
 GLIBC_2.4 __fgets_unlocked_chk F

sysdeps/unix/sysv/linux/i386/libc.abilist

@@ -2241,6 +2241,7 @@ GLIBC_2.33 mknod F
 GLIBC_2.33 mknodat F
 GLIBC_2.33 stat F
 GLIBC_2.33 stat64 F
+GLIBC_2.34 __libc_start_main F
 GLIBC_2.4 __confstr_chk F
 GLIBC_2.4 __fgets_chk F
 GLIBC_2.4 __fgets_unlocked_chk F

sysdeps/unix/sysv/linux/ia64/libc.abilist

@@ -2106,6 +2106,7 @@ GLIBC_2.33 mknod F
 GLIBC_2.33 mknodat F
 GLIBC_2.33 stat F
 GLIBC_2.33 stat64 F
+GLIBC_2.34 __libc_start_main F
 GLIBC_2.4 __confstr_chk F
 GLIBC_2.4 __fgets_chk F
 GLIBC_2.4 __fgets_unlocked_chk F

sysdeps/unix/sysv/linux/m68k/coldfire/libc.abilist

@@ -156,6 +156,7 @@ GLIBC_2.33 mknod F
 GLIBC_2.33 mknodat F
 GLIBC_2.33 stat F
 GLIBC_2.33 stat64 F
+GLIBC_2.34 __libc_start_main F
 GLIBC_2.4 _Exit F
 GLIBC_2.4 _IO_2_1_stderr_ D 0x98
 GLIBC_2.4 _IO_2_1_stdin_ D 0x98

sysdeps/unix/sysv/linux/m68k/m680x0/libc.abilist

@@ -2186,6 +2186,7 @@ GLIBC_2.33 mknod F
 GLIBC_2.33 mknodat F
 GLIBC_2.33 stat F
 GLIBC_2.33 stat64 F
+GLIBC_2.34 __libc_start_main F
 GLIBC_2.4 __confstr_chk F
 GLIBC_2.4 __fgets_chk F
 GLIBC_2.4 __fgets_unlocked_chk F

sysdeps/unix/sysv/linux/microblaze/be/libc.abilist

@@ -2166,3 +2166,4 @@ GLIBC_2.33 mknod F
 GLIBC_2.33 mknodat F
 GLIBC_2.33 stat F
 GLIBC_2.33 stat64 F
+GLIBC_2.34 __libc_start_main F

sysdeps/unix/sysv/linux/microblaze/le/libc.abilist

@@ -2163,3 +2163,4 @@ GLIBC_2.33 mknod F
 GLIBC_2.33 mknodat F
 GLIBC_2.33 stat F
 GLIBC_2.33 stat64 F
+GLIBC_2.34 __libc_start_main F

sysdeps/unix/sysv/linux/mips/mips32/fpu/libc.abilist

@@ -2157,6 +2157,7 @@ GLIBC_2.33 mknod F
 GLIBC_2.33 mknodat F
 GLIBC_2.33 stat F
 GLIBC_2.33 stat64 F
+GLIBC_2.34 __libc_start_main F
 GLIBC_2.4 __confstr_chk F
 GLIBC_2.4 __fgets_chk F
 GLIBC_2.4 __fgets_unlocked_chk F

sysdeps/unix/sysv/linux/mips/mips32/nofpu/libc.abilist

@@ -2155,6 +2155,7 @@ GLIBC_2.33 mknod F
 GLIBC_2.33 mknodat F
 GLIBC_2.33 stat F
 GLIBC_2.33 stat64 F
+GLIBC_2.34 __libc_start_main F
 GLIBC_2.4 __confstr_chk F
 GLIBC_2.4 __fgets_chk F
 GLIBC_2.4 __fgets_unlocked_chk F

sysdeps/unix/sysv/linux/mips/mips64/n32/libc.abilist

@@ -2163,6 +2163,7 @@ GLIBC_2.33 mknod F
 GLIBC_2.33 mknodat F
 GLIBC_2.33 stat F
 GLIBC_2.33 stat64 F
+GLIBC_2.34 __libc_start_main F
 GLIBC_2.4 __confstr_chk F
 GLIBC_2.4 __fgets_chk F
 GLIBC_2.4 __fgets_unlocked_chk F

sysdeps/unix/sysv/linux/mips/mips64/n64/libc.abilist

@@ -2157,6 +2157,7 @@ GLIBC_2.33 mknod F
 GLIBC_2.33 mknodat F
 GLIBC_2.33 stat F
 GLIBC_2.33 stat64 F
+GLIBC_2.34 __libc_start_main F
 GLIBC_2.4 __confstr_chk F
 GLIBC_2.4 __fgets_chk F
 GLIBC_2.4 __fgets_unlocked_chk F

sysdeps/unix/sysv/linux/nios2/libc.abilist

@@ -2204,3 +2204,4 @@ GLIBC_2.33 mknod F
 GLIBC_2.33 mknodat F
 GLIBC_2.33 stat F
 GLIBC_2.33 stat64 F
+GLIBC_2.34 __libc_start_main F

sysdeps/unix/sysv/linux/powerpc/libc-start.c

@@ -41,12 +41,12 @@ struct startup_info
   };
 
 int
-__libc_start_main (int argc, char **argv,
+__libc_start_main_impl (int argc, char **argv,
-		   char **ev,
+			char **ev,
-		   ElfW (auxv_t) * auxvec,
+			ElfW (auxv_t) * auxvec,
-		   void (*rtld_fini) (void),
+			void (*rtld_fini) (void),
-		   struct startup_info *stinfo,
+			struct startup_info *stinfo,
-		   char **stack_on_entry)
+			char **stack_on_entry)
 {
   /* the PPC SVR4 ABI says that the top thing on the stack will
      be a NULL pointer, so if not we assume that we're being called
@@ -99,3 +99,4 @@ __libc_start_main (int argc, char **argv,
 			     stinfo->init, stinfo->fini, rtld_fini,
 			     stack_on_entry);
 }
+DEFINE_LIBC_START_MAIN_VERSION

sysdeps/unix/sysv/linux/powerpc/powerpc32/fpu/libc.abilist

@@ -2213,6 +2213,7 @@ GLIBC_2.33 mknod F
 GLIBC_2.33 mknodat F
 GLIBC_2.33 stat F
 GLIBC_2.33 stat64 F
+GLIBC_2.34 __libc_start_main F
 GLIBC_2.4 _IO_fprintf F
 GLIBC_2.4 _IO_printf F
 GLIBC_2.4 _IO_sprintf F

sysdeps/unix/sysv/linux/powerpc/powerpc32/nofpu/libc.abilist

@@ -2246,6 +2246,7 @@ GLIBC_2.33 mknod F
 GLIBC_2.33 mknodat F
 GLIBC_2.33 stat F
 GLIBC_2.33 stat64 F
+GLIBC_2.34 __libc_start_main F
 GLIBC_2.4 _IO_fprintf F
 GLIBC_2.4 _IO_printf F
 GLIBC_2.4 _IO_sprintf F

sysdeps/unix/sysv/linux/powerpc/powerpc64/be/libc.abilist

@@ -2076,6 +2076,7 @@ GLIBC_2.33 mknod F
 GLIBC_2.33 mknodat F
 GLIBC_2.33 stat F
 GLIBC_2.33 stat64 F
+GLIBC_2.34 __libc_start_main F
 GLIBC_2.4 _IO_fprintf F
 GLIBC_2.4 _IO_printf F
 GLIBC_2.4 _IO_sprintf F

sysdeps/unix/sysv/linux/powerpc/powerpc64/le/libc.abilist

@@ -2366,3 +2366,4 @@ GLIBC_2.33 mknod F
 GLIBC_2.33 mknodat F
 GLIBC_2.33 stat F
 GLIBC_2.33 stat64 F
+GLIBC_2.34 __libc_start_main F

sysdeps/unix/sysv/linux/riscv/rv32/libc.abilist

@@ -1933,3 +1933,4 @@ GLIBC_2.33 wprintf F
 GLIBC_2.33 write F
 GLIBC_2.33 writev F
 GLIBC_2.33 wscanf F
+GLIBC_2.34 __libc_start_main F

sysdeps/unix/sysv/linux/riscv/rv64/libc.abilist

@@ -2133,3 +2133,4 @@ GLIBC_2.33 mknod F
 GLIBC_2.33 mknodat F
 GLIBC_2.33 stat F
 GLIBC_2.33 stat64 F
+GLIBC_2.34 __libc_start_main F

sysdeps/unix/sysv/linux/s390/s390-32/libc.abilist

@@ -2211,6 +2211,7 @@ GLIBC_2.33 mknod F
 GLIBC_2.33 mknodat F
 GLIBC_2.33 stat F
 GLIBC_2.33 stat64 F
+GLIBC_2.34 __libc_start_main F
 GLIBC_2.4 _IO_fprintf F
 GLIBC_2.4 _IO_printf F
 GLIBC_2.4 _IO_sprintf F

sysdeps/unix/sysv/linux/s390/s390-64/libc.abilist

@@ -2112,6 +2112,7 @@ GLIBC_2.33 mknod F
 GLIBC_2.33 mknodat F
 GLIBC_2.33 stat F
 GLIBC_2.33 stat64 F
+GLIBC_2.34 __libc_start_main F
 GLIBC_2.4 _IO_fprintf F
 GLIBC_2.4 _IO_printf F
 GLIBC_2.4 _IO_sprintf F

sysdeps/unix/sysv/linux/sh/be/libc.abilist

@@ -2081,6 +2081,7 @@ GLIBC_2.33 mknod F
 GLIBC_2.33 mknodat F
 GLIBC_2.33 stat F
 GLIBC_2.33 stat64 F
+GLIBC_2.34 __libc_start_main F
 GLIBC_2.4 __confstr_chk F
 GLIBC_2.4 __fgets_chk F
 GLIBC_2.4 __fgets_unlocked_chk F

sysdeps/unix/sysv/linux/sh/le/libc.abilist

@@ -2078,6 +2078,7 @@ GLIBC_2.33 mknod F
 GLIBC_2.33 mknodat F
 GLIBC_2.33 stat F
 GLIBC_2.33 stat64 F
+GLIBC_2.34 __libc_start_main F
 GLIBC_2.4 __confstr_chk F
 GLIBC_2.4 __fgets_chk F
 GLIBC_2.4 __fgets_unlocked_chk F

sysdeps/unix/sysv/linux/sparc/sparc32/libc.abilist

@@ -2202,6 +2202,7 @@ GLIBC_2.33 mknod F
 GLIBC_2.33 mknodat F
 GLIBC_2.33 stat F
 GLIBC_2.33 stat64 F
+GLIBC_2.34 __libc_start_main F
 GLIBC_2.4 _IO_fprintf F
 GLIBC_2.4 _IO_printf F
 GLIBC_2.4 _IO_sprintf F

sysdeps/unix/sysv/linux/sparc/sparc64/libc.abilist

@@ -2129,6 +2129,7 @@ GLIBC_2.33 mknod F
 GLIBC_2.33 mknodat F
 GLIBC_2.33 stat F
 GLIBC_2.33 stat64 F
+GLIBC_2.34 __libc_start_main F
 GLIBC_2.4 __confstr_chk F
 GLIBC_2.4 __fgets_chk F
 GLIBC_2.4 __fgets_unlocked_chk F

sysdeps/unix/sysv/linux/x86_64/64/libc.abilist

@@ -2088,6 +2088,7 @@ GLIBC_2.33 mknod F
 GLIBC_2.33 mknodat F
 GLIBC_2.33 stat F
 GLIBC_2.33 stat64 F
+GLIBC_2.34 __libc_start_main F
 GLIBC_2.4 __confstr_chk F
 GLIBC_2.4 __fgets_chk F
 GLIBC_2.4 __fgets_unlocked_chk F

sysdeps/unix/sysv/linux/x86_64/x32/libc.abilist

@@ -2185,3 +2185,4 @@ GLIBC_2.33 mknod F
 GLIBC_2.33 mknodat F
 GLIBC_2.33 stat F
 GLIBC_2.33 stat64 F
+GLIBC_2.34 __libc_start_main F

sysdeps/x86_64/start.S

@@ -96,17 +96,13 @@ ENTRY (_start)
 	   which grow downwards).  */
 	pushq %rsp
 
-#ifdef PIC
+	/* These used to be the addresses of .fini and .init.  */
-	/* Pass address of our own entry points to .fini and .init.  */
+	xorl %r8d, %r8d
-	mov __libc_csu_fini@GOTPCREL(%rip), %R8_LP
+	xorl %ecx, %ecx
-	mov __libc_csu_init@GOTPCREL(%rip), %RCX_LP
 
+#ifdef PIC
 	mov main@GOTPCREL(%rip), %RDI_LP
 #else
-	/* Pass address of our own entry points to .fini and .init.  */
-	mov $__libc_csu_fini, %R8_LP
-	mov $__libc_csu_init, %RCX_LP
-
 	mov $main, %RDI_LP
 #endif