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-rw-r--r--hurd/dtable.c8
-rw-r--r--hurd/hurdid.c7
-rw-r--r--hurd/hurdinit.c6
-rw-r--r--hurd/hurdmalloc.c10
-rw-r--r--hurd/hurdpid.c7
-rw-r--r--hurd/hurdrlimit.c7
-rw-r--r--hurd/hurdsock.c7
-rw-r--r--include/set-hooks.h25
-rw-r--r--sysdeps/generic/set-hooks-arch.h31
-rw-r--r--sysdeps/i386/set-hooks-arch.h28
-rw-r--r--sysdeps/mach/hurd/brk.c8
-rw-r--r--sysdeps/mach/hurd/check_fds.c6
-rw-r--r--sysdeps/mach/hurd/i386/init-first.c2
-rw-r--r--sysdeps/x86_64/set-hooks-arch.h28
14 files changed, 140 insertions, 40 deletions
diff --git a/hurd/dtable.c b/hurd/dtable.c
index bbd3bfc892..4f081f09fd 100644
--- a/hurd/dtable.c
+++ b/hurd/dtable.c
@@ -36,7 +36,7 @@ DEFINE_HOOK (_hurd_fd_subinit, (void));
 
 /* Initialize the file descriptor table at startup.  */
 
-static void
+static void attribute_used_retain
 init_dtable (void)
 {
   int i;
@@ -91,12 +91,10 @@ init_dtable (void)
 
   /* Run things that want to run after the file descriptor table
      is initialized.  */
-  RUN_HOOK (_hurd_fd_subinit, ());
-
-  (void) &init_dtable;		/* Avoid "defined but not used" warning.  */
+  RUN_RELHOOK (_hurd_fd_subinit, ());
 }
 
-text_set_element (_hurd_subinit, init_dtable);
+SET_RELHOOK (_hurd_subinit, init_dtable);
 
 /* XXX when the linker supports it, the following functions should all be
    elsewhere and just have text_set_elements here.  */
diff --git a/hurd/hurdid.c b/hurd/hurdid.c
index 70c46c0740..b220532c35 100644
--- a/hurd/hurdid.c
+++ b/hurd/hurdid.c
@@ -17,6 +17,7 @@
 
 #include <hurd.h>
 #include <hurd/id.h>
+#include "set-hooks.h"
 
 struct hurd_id_data _hurd_id;
 
@@ -74,7 +75,7 @@ _hurd_check_ids (void)
   return 0;
 }
 
-static void
+static void attribute_used_retain
 init_id (void)
 {
   __mutex_init (&_hurd_id.lock);
@@ -84,7 +85,5 @@ init_id (void)
   _hurd_id.gen.nuids = _hurd_id.aux.nuids = 0;
   _hurd_id.gen.gids = _hurd_id.aux.gids = NULL;
   _hurd_id.gen.ngids = _hurd_id.aux.ngids = 0;
-
-  (void) &init_id;		/* Avoid "defined but not used" warning.  */
 }
-text_set_element (_hurd_preinit_hook, init_id);
+SET_RELHOOK (_hurd_preinit_hook, init_id);
diff --git a/hurd/hurdinit.c b/hurd/hurdinit.c
index d4d219a083..9377d902d2 100644
--- a/hurd/hurdinit.c
+++ b/hurd/hurdinit.c
@@ -108,7 +108,7 @@ _hurd_init (int flags, char **argv,
   /* Call other things which want to do some initialization.  These are not
      on the __libc_subinit hook because things there like to be able to
      assume the availability of the POSIX.1 services we provide.  */
-  RUN_HOOK (_hurd_subinit, ());
+  RUN_RELHOOK (_hurd_subinit, ());
 }
 libc_hidden_def (_hurd_init)
 
@@ -190,7 +190,7 @@ _hurd_new_proc_init (char **argv,
   /* Call other things which want to do some initialization.  These are not
      on the _hurd_subinit hook because things there assume that things done
      here, like _hurd_pid, are already initialized.  */
-  RUN_HOOK (_hurd_proc_subinit, ());
+  RUN_RELHOOK (_hurd_proc_subinit, ());
 
   /* XXX This code should probably be removed entirely at some point.  This
      conditional should make it reasonably usable with old gdb's for a
@@ -242,7 +242,7 @@ _hurd_setproc (process_t procserver)
 
     /* Call these functions again so they can fetch the
        new information from the new proc server.  */
-    RUN_HOOK (_hurd_proc_subinit, ());
+    RUN_RELHOOK (_hurd_proc_subinit, ());
 
     if (_hurd_pgrp != oldpgrp)
       {
diff --git a/hurd/hurdmalloc.c b/hurd/hurdmalloc.c
index 7046bcef33..ccb8fc8b54 100644
--- a/hurd/hurdmalloc.c
+++ b/hurd/hurdmalloc.c
@@ -1,5 +1,6 @@
 #include <stdlib.h>
 #include <string.h>
+#include "set-hooks.h"
 
 #include "hurdmalloc.h"		/* XXX see that file */
 
@@ -148,7 +149,7 @@ static struct free_list malloc_free_list[NBUCKETS];
    It preserves the values of data variables like malloc_free_list, but
    does not save the vm_allocate'd space allocated by this malloc.  */
 
-static void
+static void attribute_used_retain
 malloc_init (void)
 {
   int i;
@@ -160,11 +161,6 @@ malloc_init (void)
       malloc_free_list[i].in_use = 0;
 #endif
     }
-
-  /* This not only suppresses a `defined but not used' warning,
-     but it is ABSOLUTELY NECESSARY to avoid the hyperclever
-     compiler from "optimizing out" the entire function!  */
-  (void) &malloc_init;
 }
 
 static void
@@ -445,4 +441,4 @@ _hurd_malloc_fork_child(void)
 }
 
 
-text_set_element (_hurd_preinit_hook, malloc_init);
+SET_RELHOOK (_hurd_preinit_hook, malloc_init);
diff --git a/hurd/hurdpid.c b/hurd/hurdpid.c
index 9014de58e9..613ca357c6 100644
--- a/hurd/hurdpid.c
+++ b/hurd/hurdpid.c
@@ -17,11 +17,12 @@
 
 #include <hurd.h>
 #include <lowlevellock.h>
+#include "set-hooks.h"
 
 pid_t _hurd_pid, _hurd_ppid, _hurd_pgrp;
 int _hurd_orphaned;
 
-static void
+static void attribute_used_retain
 init_pids (void)
 {
   __USEPORT (PROC,
@@ -29,11 +30,9 @@ init_pids (void)
 	       __proc_getpids (port, &_hurd_pid, &_hurd_ppid, &_hurd_orphaned);
 	       __proc_getpgrp (port, _hurd_pid, &_hurd_pgrp);
 	     }));
-
-  (void) &init_pids;		/* Avoid "defined but not used" warning.  */
 }
 
-text_set_element (_hurd_proc_subinit, init_pids);
+SET_RELHOOK (_hurd_proc_subinit, init_pids);
 
 #include <hurd/msg_server.h>
 #include "set-hooks.h"
diff --git a/hurd/hurdrlimit.c b/hurd/hurdrlimit.c
index 17535c2851..4d16bd4f3f 100644
--- a/hurd/hurdrlimit.c
+++ b/hurd/hurdrlimit.c
@@ -19,6 +19,7 @@
 #include <hurd.h>
 #include <lock-intern.h>
 #include <hurd/resource.h>
+#include "set-hooks.h"
 
 /* This must be given an initializer, or the a.out linking rules will
    not include the entire file when this symbol is referenced. */
@@ -29,7 +30,7 @@ struct rlimit _hurd_rlimits[RLIM_NLIMITS] = { { 0, }, };
    mutex_init is still required below just in case of unexec.  */
 struct mutex _hurd_rlimit_lock = { SPIN_LOCK_INITIALIZER, };
 
-static void
+static void attribute_used_retain
 init_rlimit (void)
 {
   int i;
@@ -52,7 +53,5 @@ init_rlimit (void)
 	  }
 #undef	I
     }
-
-  (void) &init_rlimit;
 }
-text_set_element (_hurd_preinit_hook, init_rlimit);
+SET_RELHOOK (_hurd_preinit_hook, init_rlimit);
diff --git a/hurd/hurdsock.c b/hurd/hurdsock.c
index 04e86b4324..116326b2f2 100644
--- a/hurd/hurdsock.c
+++ b/hurd/hurdsock.c
@@ -25,6 +25,7 @@
 #include <_itoa.h>
 #include <lock-intern.h>	/* For `struct mutex'.  */
 #include "hurdmalloc.h"		/* XXX */
+#include "set-hooks.h"
 
 static struct mutex lock;
 
@@ -109,7 +110,7 @@ retry:
   return server;
 }
 
-static void
+static void attribute_used_retain
 init (void)
 {
   int i;
@@ -118,7 +119,5 @@ init (void)
 
   for (i = 0; i < max_domain; ++i)
     servers[i] = MACH_PORT_NULL;
-
-  (void) &init;			/* Avoid "defined but not used" warning.  */
 }
-text_set_element (_hurd_preinit_hook, init);
+SET_RELHOOK (_hurd_preinit_hook, init);
diff --git a/include/set-hooks.h b/include/set-hooks.h
index a60b5ae19f..1a2f6ad56b 100644
--- a/include/set-hooks.h
+++ b/include/set-hooks.h
@@ -24,6 +24,8 @@
 #include <sys/cdefs.h>
 #include <libc-symbols.h>
 
+#include "set-hooks-arch.h"
+
 #ifdef symbol_set_define
 /* Define a hook variable called NAME.  Functions put on this hook take
    arguments described by PROTO.  Use `text_set_element (NAME, FUNCTION)'
@@ -55,6 +57,25 @@ do {									      \
 DEFINE_HOOK (name, proto); \
 extern void runner proto; void runner proto { RUN_HOOK (name, args); }
 
+# ifdef SET_RELHOOK
+/* This is similar to RUN_RELHOOK, but the hooks were registered with
+ * SET_RELHOOK so that a relative offset was computed by the linker
+ * rather than an absolute address by the dynamic linker. */
+#  define RUN_RELHOOK(NAME, ARGS)				      \
+do {								      \
+  void *const *ptr;						      \
+  for (ptr = (void *const *) symbol_set_first_element (NAME);	      \
+       ! symbol_set_end_p (NAME, ptr); ++ptr) {			      \
+    __##NAME##_hook_function_t *f =				      \
+	(void*) ((uintptr_t) ptr + (ptrdiff_t) *ptr);		      \
+    (*f) ARGS;							      \
+  } \
+} while (0)
+# else
+#  define SET_RELHOOK(NAME, HOOK) text_set_element (NAME, HOOK)
+#  define RUN_RELHOOK(NAME, ARGS) RUN_HOOK(NAME, ARGS)
+# endif
+
 #else
 
 /* The system does not provide necessary support for this.  */
@@ -66,6 +87,10 @@ extern void runner proto; void runner proto { RUN_HOOK (name, args); }
 
 # define DEFINE_HOOK_RUNNER(name, runner, proto, args)
 
+# define SET_RELHOOK(NAME, HOOK)
+
+# define RUN_RELHOOK(NAME, ARGS)
+
 #endif
 
 #endif /* set-hooks.h */
diff --git a/sysdeps/generic/set-hooks-arch.h b/sysdeps/generic/set-hooks-arch.h
new file mode 100644
index 0000000000..4b47fa2f2e
--- /dev/null
+++ b/sysdeps/generic/set-hooks-arch.h
@@ -0,0 +1,31 @@
+/* Machine-dependent macros for using symbol sets for running lists of
+   functions. Generic/stub version.
+   Copyright (C) 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.
+
+   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/>.  */
+
+#ifndef _SET_HOOKS_ARCH_H
+#define _SET_HOOKS_ARCH_H
+
+/* Define SET_RELHOOK to a variant of text_set_element that records a relative
+   offset rather than an absolute address. See sysdeps/i386/set-hooks-arch.h
+   for an example.
+
+#define SET_RELHOOK(NAME, HOOK) ...
+
+ */
+
+#endif /* set_hooks_arch.h */
diff --git a/sysdeps/i386/set-hooks-arch.h b/sysdeps/i386/set-hooks-arch.h
new file mode 100644
index 0000000000..97513bf897
--- /dev/null
+++ b/sysdeps/i386/set-hooks-arch.h
@@ -0,0 +1,28 @@
+/* Machine-dependent macros for using symbol sets for running lists of
+   functions. i386 version.
+   Copyright (C) 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.
+
+   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/>.  */
+
+#ifndef _SET_HOOKS_ARCH_H
+#define _SET_HOOKS_ARCH_H
+
+#define SET_RELHOOK(NAME, HOOK) \
+	asm(".section " #NAME",\"aR\"\n" \
+	    ".long "#HOOK" - .\n" \
+	    ".section .text");
+
+#endif /* set_hooks_arch.h */
diff --git a/sysdeps/mach/hurd/brk.c b/sysdeps/mach/hurd/brk.c
index a4294b9eae..088c99b2c8 100644
--- a/sysdeps/mach/hurd/brk.c
+++ b/sysdeps/mach/hurd/brk.c
@@ -21,6 +21,8 @@
 #include <lock-intern.h>	/* For `struct mutex'.  */
 #include <vm_param.h>
 
+#include "set-hooks.h"
+
 
 /* Initial maximum size of the data segment (this is arbitrary).  */
 #define	DATA_SIZE	(128 * 1024 * 1024)
@@ -130,7 +132,7 @@ _hurd_set_brk (vm_address_t addr)
   return 0;
 }
 
-static void
+static void attribute_used_retain
 init_brk (void)
 {
   vm_address_t pagend;
@@ -160,7 +162,5 @@ init_brk (void)
 	/* Couldn't allocate the memory.  The break will be very short.  */
 	_hurd_data_end = pagend;
     }
-
-  (void) &init_brk;		/* Avoid ``defined but not used'' warning.  */
 }
-text_set_element (_hurd_preinit_hook, init_brk);
+SET_RELHOOK (_hurd_preinit_hook, init_brk);
diff --git a/sysdeps/mach/hurd/check_fds.c b/sysdeps/mach/hurd/check_fds.c
index 155e9dd3e9..61e6055d35 100644
--- a/sysdeps/mach/hurd/check_fds.c
+++ b/sysdeps/mach/hurd/check_fds.c
@@ -79,7 +79,7 @@ check_standard_fds (void)
   check_one_fd (STDERR_FILENO, O_RDWR);
 }
 
-static void
+static void attribute_used_retain
 init_standard_fds (void)
 {
   /* Now that we have FDs, make sure that, if this is a SUID program,
@@ -87,10 +87,8 @@ init_standard_fds (void)
      ourselves.  If that's not possible we stop the program.  */
   if (__builtin_expect (__libc_enable_secure, 0))
     check_standard_fds ();
-
-  (void) &init_standard_fds;	/* Avoid "defined but not used" warning.  */
 }
-text_set_element (_hurd_fd_subinit, init_standard_fds);
+SET_RELHOOK (_hurd_fd_subinit, init_standard_fds);
 
 
 #ifndef SHARED
diff --git a/sysdeps/mach/hurd/i386/init-first.c b/sysdeps/mach/hurd/i386/init-first.c
index 5e85aa2bc5..c6ae370daf 100644
--- a/sysdeps/mach/hurd/i386/init-first.c
+++ b/sysdeps/mach/hurd/i386/init-first.c
@@ -242,7 +242,7 @@ first_init (void)
   /* Initialize data structures so we can do RPCs.  */
   __mach_init ();
 
-  RUN_HOOK (_hurd_preinit_hook, ());
+  RUN_RELHOOK (_hurd_preinit_hook, ());
 }
 
 #ifdef SHARED
diff --git a/sysdeps/x86_64/set-hooks-arch.h b/sysdeps/x86_64/set-hooks-arch.h
new file mode 100644
index 0000000000..227d4f8e08
--- /dev/null
+++ b/sysdeps/x86_64/set-hooks-arch.h
@@ -0,0 +1,28 @@
+/* Machine-dependent macros for using symbol sets for running lists of
+   functions. x86-64 version.
+   Copyright (C) 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.
+
+   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/>.  */
+
+#ifndef _SET_HOOKS_ARCH_H
+#define _SET_HOOKS_ARCH_H
+
+#define SET_RELHOOK(NAME, HOOK) \
+	asm(".section " #NAME",\"aR\"\n" \
+	    ".quad "#HOOK" - .\n" \
+	    ".section .text");
+
+#endif /* set_hooks_arch.h */
generated by cgit-pink 1.4.1 (git 2.36.1) at 2024-08-16 02:15:40 +0000