commit 35fcb4fc81e51295d14125785765e0ea3e132cd9

Author: Pedro Alves <palves@redhat.com>

Date:   Tue Aug 9 20:21:08 2016 +0100

    Fix PR gdb/18653: gdb disturbs inferior's inherited signal dispositions

    gdb's (or gdbserver's) own signal handling should not interfere with

    the signal dispositions their spawned children inherit.  However, it

    currently does.  For example, some paths in gdb cause SIGPIPE to be

    set to SIG_IGN, and as consequence, the child starts with SIGPIPE to

    set to SIG_IGN too, even though gdb was started with SIGPIPE set to

    SIG_DFL.

    This is because the exec family of functions does not reset the signal

    disposition of signals that are set to SIG_IGN:

      http://pubs.opengroup.org/onlinepubs/7908799/xsh/execve.html

      Signals set to the default action (SIG_DFL) in the calling process

      image are set to the default action in the new process

      image. Signals set to be ignored (SIG_IGN) by the calling process

      image are set to be ignored by the new process image. Signals set to

      be caught by the calling process image are set to the default action

      in the new process image (see <signal.h>).

    And neither does it reset signal masks or flags.

    In order to be transparent, when spawning new child processes to debug

    (with "run", etc.), reset signal actions and mask back to what was

    originally inherited from gdb/gdbserver's parent, just before execing

    the target program to debug.

    gdb/ChangeLog:

    2016-08-09  Pedro Alves  <palves@redhat.com>

            PR gdb/18653

            * Makefile.in (SFILES): Add

            common/signals-state-save-restore.c.

            (HFILES_NO_SRCDIR): Add common/signals-state-save-restore.h.

            (COMMON_OBS): Add signals-state-save-restore.o.

            (signals-state-save-restore.o): New rule.

            * configure: Regenerate.

            * fork-child.c: Include "signals-state-save-restore.h".

            (fork_inferior): Call restore_original_signals_state.

            * main.c: Include "signals-state-save-restore.h".

            (captured_main): Call save_original_signals_state.

            * common/common.m4: Add sigaction to AC_CHECK_FUNCS checks.

            * common/signals-state-save-restore.c: New file.

            * common/signals-state-save-restore.h: New file.

    gdb/gdbserver/ChangeLog:

    2016-08-09  Pedro Alves  <palves@redhat.com>

            PR gdb/18653

            * Makefile.in (OBS): Add signals-state-save-restore.o.

            (signals-state-save-restore.o): New rule.

            * config.in: Regenerate.

            * configure: Regenerate.

            * linux-low.c: Include "signals-state-save-restore.h".

            (linux_create_inferior): Call

            restore_original_signals_state.

            * server.c: Include "dispositions-save-restore.h".

            (captured_main): Call save_original_signals_state.

    gdb/testsuite/ChangeLog:

    2016-08-09  Pedro Alves  <palves@redhat.com>

            PR gdb/18653

            * gdb.base/signals-state-child.c: New file.

            * gdb.base/signals-state-child.exp: New file.

            * gdb.gdb/selftest.exp (do_steps_and_nexts): Add new pattern.

### a/gdb/ChangeLog

### b/gdb/ChangeLog

## -1,5 +1,22 @@

 2016-08-09  Pedro Alves  <palves@redhat.com>

+	PR gdb/18653

+	* Makefile.in (SFILES): Add

+	common/signals-state-save-restore.c.

+	(HFILES_NO_SRCDIR): Add common/signals-state-save-restore.h.

+	(COMMON_OBS): Add signals-state-save-restore.o.

+	(signals-state-save-restore.o): New rule.

+	* configure: Regenerate.

+	* fork-child.c: Include "signals-state-save-restore.h".

+	(fork_inferior): Call restore_original_signals_state.

+	* main.c: Include "signals-state-save-restore.h".

+	(captured_main): Call save_original_signals_state.

+	* common/common.m4: Add sigaction to AC_CHECK_FUNCS checks.

+	* common/signals-state-save-restore.c: New file.

+	* common/signals-state-save-restore.h: New file.

+

+2016-08-09  Pedro Alves  <palves@redhat.com>

+

 	* value.c (unpack_value_bitfield): Skip unpacking if the parent

 	has no contents buffer to begin with.

Index: gdb-7.6.1/gdb/Makefile.in

===================================================================

--- gdb-7.6.1.orig/gdb/Makefile.in	2017-11-03 19:22:10.364013263 +0100

+++ gdb-7.6.1/gdb/Makefile.in	2017-11-03 19:22:11.452021206 +0100

@@ -763,7 +763,8 @@

 	regset.c sol-thread.c windows-termcap.c \

 	common/gdb_vecs.c common/common-utils.c common/xml-utils.c \

 	common/ptid.c common/buffer.c gdb-dlfcn.c common/agent.c \

-	common/format.c btrace.c record-btrace.c

+	common/format.c btrace.c record-btrace.c \

+	common/signals-state-save-restore.c \

 LINTFILES = $(SFILES) $(YYFILES) $(CONFIG_SRCS) init.c

@@ -841,7 +842,8 @@

 common/format.h common/host-defs.h utils.h common/queue.h common/gdb_string.h \

 common/linux-osdata.h gdb-dlfcn.h auto-load.h probe.h stap-probe.h \

 gdb_bfd.h sparc-ravenscar-thread.h ppc-ravenscar-thread.h common/linux-btrace.h \

-nat/linux-namespaces.h

+nat/linux-namespaces.h \

+common/signals-state-save-restore.h

 # Header files that already have srcdir in them, or which are in objdir.

@@ -898,6 +900,7 @@

 	memattr.o mem-break.o target.o parse.o language.o buildsym.o \

 	findcmd.o \

 	std-regs.o \

+	signals-state-save-restore.o \

 	signals.o \

 	exec.o reverse.o \

 	bcache.o objfiles.o observer.o minsyms.o maint.o demangle.o \

@@ -2116,6 +2119,10 @@

 	$(COMPILE) $(srcdir)/tui/tui-winsource.c

 	$(POSTCOMPILE)

+signals-state-save-restore.o: $(srcdir)/common/signals-state-save-restore.c

+	$(COMPILE) $(srcdir)/common/signals-state-save-restore.c

+	$(POSTCOMPILE)

+

 #

 # gdb/python/ dependencies

 #

Index: gdb-7.6.1/gdb/common/signals-state-save-restore.c

===================================================================

--- /dev/null	1970-01-01 00:00:00.000000000 +0000

+++ gdb-7.6.1/gdb/common/signals-state-save-restore.c	2017-11-03 19:33:46.346074718 +0100

@@ -0,0 +1,99 @@

+/* Copyright (C) 2016 Free Software Foundation, Inc.

+

+   This file is part of GDB.

+

+   This program is free software; you can redistribute it and/or modify

+   it under the terms of the GNU General Public License as published by

+   the Free Software Foundation; either version 3 of the License, or

+   (at your option) any later version.

+

+   This program 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 General Public License for more details.

+

+   You should have received a copy of the GNU General Public License

+   along with this program.  If not, see <http://www.gnu.org/licenses/>.  */

+

+#ifdef GDBSERVER

+#include "server.h"

+#else

+#include "defs.h"

+#endif

+

+#include "signals-state-save-restore.h"

+

+#include <signal.h>

+

+/* The original signal actions and mask.  */

+

+#ifdef HAVE_SIGACTION

+static struct sigaction original_signal_actions[NSIG];

+

+/* Note that we use sigprocmask without worrying about threads because

+   the save/restore functions are called either from main, or after a

+   fork.  In both cases, we know the calling process is single

+   threaded.  */

+static sigset_t original_signal_mask;

+#endif

+

+/* See signals-state-save-restore.h.   */

+

+void

+save_original_signals_state (void)

+{

+#ifdef HAVE_SIGACTION

+  int i;

+  int res;

+

+  res = sigprocmask (0,  NULL, &original_signal_mask);

+  if (res == -1)

+    perror_with_name ("sigprocmask");

+

+  for (i = 1; i < NSIG; i++)

+    {

+      struct sigaction *oldact = &original_signal_actions[i];

+

+      res = sigaction (i, NULL, oldact);

+      if (res == -1 && errno == EINVAL)

+	{

+	  /* Some signal numbers in the range are invalid.  */

+	  continue;

+	}

+      else if (res == -1)

+	perror_with_name ("sigaction");

+

+      /* If we find a custom signal handler already installed, then

+	 this function was called too late.  */

+      if (oldact->sa_handler != SIG_DFL && oldact->sa_handler != SIG_IGN)

+	internal_error (__FILE__, __LINE__, _("unexpected signal handler"));

+    }

+#endif

+}

+

+/* See signals-state-save-restore.h.   */

+

+void

+restore_original_signals_state (void)

+{

+#ifdef HAVE_SIGACTION

+  int i;

+  int res;

+

+  for (i = 1; i < NSIG; i++)

+    {

+      res = sigaction (i, &original_signal_actions[i], NULL);

+      if (res == -1 && errno == EINVAL)

+	{

+	  /* Some signal numbers in the range are invalid.  */

+	  continue;

+	}

+      else if (res == -1)

+	perror_with_name ("sigaction");

+    }

+

+  res = sigprocmask (SIG_SETMASK,  &original_signal_mask, NULL);

+  if (res == -1)

+    perror_with_name ("sigprocmask");

+#endif

+}

Index: gdb-7.6.1/gdb/common/signals-state-save-restore.h

===================================================================

--- /dev/null	1970-01-01 00:00:00.000000000 +0000

+++ gdb-7.6.1/gdb/common/signals-state-save-restore.h	2017-11-03 19:22:11.453021213 +0100

@@ -0,0 +1,39 @@

+/* Copyright (C) 2016 Free Software Foundation, Inc.

+

+   This file is part of GDB.

+

+   This program is free software; you can redistribute it and/or modify

+   it under the terms of the GNU General Public License as published by

+   the Free Software Foundation; either version 3 of the License, or

+   (at your option) any later version.

+

+   This program 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 General Public License for more details.

+

+   You should have received a copy of the GNU General Public License

+   along with this program.  If not, see <http://www.gnu.org/licenses/>.  */

+

+#ifndef COMMON_SIGNALS_STATE_SAVE_RESTORE_H

+#define COMMON_SIGNALS_STATE_SAVE_RESTORE_H

+

+/* Save/restore the signal actions of all signals, and the signal

+   mask.

+

+   Since the exec family of functions does not reset the signal

+   disposition of signals set to SIG_IGN, nor does it reset the signal

+   mask, in order to be transparent, when spawning new child processes

+   to debug (with "run", etc.), we must reset signal actions and mask

+   back to what was originally inherited from gdb/gdbserver's parent,

+   just before execing the target program to debug.  */

+

+/* Save the signal state of all signals.  */

+

+extern void save_original_signals_state (void);

+

+/* Restore the signal state of all signals.  */

+

+extern void restore_original_signals_state (void);

+

+#endif /* COMMON_SIGNALS_STATE_SAVE_RESTORE_H */

Index: gdb-7.6.1/gdb/configure

===================================================================

--- gdb-7.6.1.orig/gdb/configure	2017-11-03 19:22:08.181997334 +0100

+++ gdb-7.6.1/gdb/configure	2017-11-03 19:22:11.455021228 +0100

@@ -10667,7 +10667,7 @@

 		sbrk setpgid setpgrp setsid \

 		sigaction sigprocmask sigsetmask socketpair syscall \

 		ttrace wborder wresize setlocale iconvlist libiconvlist btowc \

-		setrlimit getrlimit posix_madvise waitpid lstat

+		setrlimit getrlimit posix_madvise waitpid lstat sigaction

 do :

   as_ac_var=`$as_echo "ac_cv_func_$ac_func" | $as_tr_sh`

 ac_fn_c_check_func "$LINENO" "$ac_func" "$as_ac_var"

Index: gdb-7.6.1/gdb/fork-child.c

===================================================================

--- gdb-7.6.1.orig/gdb/fork-child.c	2013-01-01 07:32:42.000000000 +0100

+++ gdb-7.6.1/gdb/fork-child.c	2017-11-03 19:22:11.455021228 +0100

@@ -32,7 +32,7 @@

 #include "command.h" /* for dont_repeat () */

 #include "gdbcmd.h"

 #include "solib.h"

-

+#include "signals-state-save-restore.h"

 #include <signal.h>

 /* This just gets used as a default if we can't find SHELL.  */

@@ -350,6 +350,8 @@

         saying "not parent".  Sorry; you'll have to use print

         statements!  */

+      restore_original_signals_state ();

+

       /* There is no execlpe call, so we have to set the environment

          for our child in the global variable.  If we've vforked, this

          clobbers the parent, but environ is restored a few lines down

Index: gdb-7.6.1/gdb/gdbserver/Makefile.in

===================================================================

--- gdb-7.6.1.orig/gdb/gdbserver/Makefile.in	2017-11-03 19:22:10.364013263 +0100

+++ gdb-7.6.1/gdb/gdbserver/Makefile.in	2017-11-03 19:22:11.455021228 +0100

@@ -170,6 +170,7 @@

 	mem-break.o hostio.o event-loop.o tracepoint.o \

 	xml-utils.o common-utils.o ptid.o buffer.o format.o \

 	dll.o notif.o \

+	signals-state-save-restore.o \

 	$(XML_BUILTIN) \

 	$(DEPFILES) $(LIBOBJS)

 GDBREPLAY_OBS = gdbreplay.o version.o

@@ -572,6 +573,9 @@

 linux-namespaces.o: ../nat/linux-namespaces.c

 	$(COMPILE) $<

 	$(POSTCOMPILE)

+signals-state-save-restore.o: ../common/signals-state-save-restore.c

+	$(COMPILE) $<

+	$(POSTCOMPILE)

 win32_low_h = $(srcdir)/win32-low.h

Index: gdb-7.6.1/gdb/gdbserver/config.in

===================================================================

--- gdb-7.6.1.orig/gdb/gdbserver/config.in	2017-11-03 19:22:10.364013263 +0100

+++ gdb-7.6.1/gdb/gdbserver/config.in	2017-11-03 19:22:11.455021228 +0100

@@ -152,6 +152,9 @@

 /* Define to 1 if you have the <sgtty.h> header file. */

 #undef HAVE_SGTTY_H

+/* Define to 1 if you have the `sigaction' function. */

+#undef HAVE_SIGACTION

+

 /* Define to 1 if you have the <signal.h> header file. */

 #undef HAVE_SIGNAL_H

Index: gdb-7.6.1/gdb/gdbserver/configure

===================================================================

--- gdb-7.6.1.orig/gdb/gdbserver/configure	2017-11-03 19:22:10.366013278 +0100

+++ gdb-7.6.1/gdb/gdbserver/configure	2017-11-03 19:22:11.456021235 +0100

@@ -4796,7 +4796,7 @@

 done

-for ac_func in pread pwrite pread64 readlink setns

+for ac_func in pread pwrite pread64 readlink setns sigaction

 do :

   as_ac_var=`$as_echo "ac_cv_func_$ac_func" | $as_tr_sh`

 ac_fn_c_check_func "$LINENO" "$ac_func" "$as_ac_var"

Index: gdb-7.6.1/gdb/gdbserver/linux-low.c

===================================================================

--- gdb-7.6.1.orig/gdb/gdbserver/linux-low.c	2017-11-03 19:22:10.380013380 +0100

+++ gdb-7.6.1/gdb/gdbserver/linux-low.c	2017-11-03 19:22:11.457021243 +0100

@@ -20,7 +20,7 @@

 #include "linux-low.h"

 #include "linux-osdata.h"

 #include "agent.h"

-

+#include "signals-state-save-restore.h"

 #include "gdb_wait.h"

 #include <stdio.h>

 #include <sys/param.h>

@@ -699,6 +699,8 @@

 	    close (remote_desc);

 	}

+      restore_original_signals_state ();

+

       execv (program, allargs);

       if (errno == ENOENT)

 	execvp (program, allargs);

Index: gdb-7.6.1/gdb/gdbserver/server.c

===================================================================

--- gdb-7.6.1.orig/gdb/gdbserver/server.c	2017-11-03 19:22:10.380013380 +0100

+++ gdb-7.6.1/gdb/gdbserver/server.c	2017-11-03 19:22:11.457021243 +0100

@@ -20,7 +20,7 @@

 #include "gdbthread.h"

 #include "agent.h"

 #include "notif.h"

-

+#include "signals-state-save-restore.h"

 #if HAVE_UNISTD_H

 #include <unistd.h>

 #endif

@@ -2896,6 +2896,8 @@

       exit (1);

     }

+  save_original_signals_state ();

+

   /* We need to know whether the remote connection is stdio before

      starting the inferior.  Inferiors created in this scenario have

      stdin,stdout redirected.  So do this here before we call

Index: gdb-7.6.1/gdb/main.c

===================================================================

--- gdb-7.6.1.orig/gdb/main.c	2017-11-03 19:22:10.319012935 +0100

+++ gdb-7.6.1/gdb/main.c	2017-11-03 19:22:11.458021250 +0100

@@ -45,6 +45,7 @@

 #include "auto-load.h"

 #include "filenames.h"

+#include "signals-state-save-restore.h"

 /* The selected interpreter.  This will be used as a set command

    variable, so it should always be malloc'ed - since

@@ -393,6 +394,7 @@

   textdomain (PACKAGE);

   bfd_init ();

+  save_original_signals_state ();

   make_cleanup (VEC_cleanup (cmdarg_s), &cmdarg_vec);

   dirsize = 1;

Index: gdb-7.6.1/gdb/testsuite/gdb.base/signals-state-child.c

===================================================================

--- /dev/null	1970-01-01 00:00:00.000000000 +0000

+++ gdb-7.6.1/gdb/testsuite/gdb.base/signals-state-child.c	2017-11-03 19:22:11.458021250 +0100

@@ -0,0 +1,101 @@

+/* Copyright 2016 Free Software Foundation, Inc.

+

+   This file is part of GDB.

+

+   This program is free software; you can redistribute it and/or modify

+   it under the terms of the GNU General Public License as published by

+   the Free Software Foundation; either version 3 of the License, or

+   (at your option) any later version.

+

+   This program 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 General Public License for more details.

+

+   You should have received a copy of the GNU General Public License

+   along with this program.  If not, see <http://www.gnu.org/licenses/>.  */

+

+#include <stdlib.h>

+#include <stdio.h>

+#include <signal.h>

+#include <assert.h>

+#include <errno.h>

+

+#ifndef OUTPUT_TXT

+# define OUTPUT_TXT "output.txt"

+#endif

+

+static void

+perror_and_exit (const char *s)

+{

+  perror (s);

+  exit (1);

+}

+

+int

+main (int argc, char **argv)

+{

+  int i;

+  FILE *out;

+  sigset_t sigset;

+  int res;

+

+  res = sigprocmask (0,  NULL, &sigset);

+  if (res != 0)

+    perror_and_exit ("sigprocmask");

+

+  if (argc > 1)

+    out = stdout;

+  else

+    {

+      out = fopen (OUTPUT_TXT, "w");

+      if (out == NULL)

+	perror_and_exit ("fopen");

+    }

+

+  for (i = 1; i < NSIG; i++)

+    {

+      struct sigaction oldact;

+

+      fprintf (out, "signal %d: ", i);

+

+      res = sigaction (i, NULL, &oldact);

+      if (res == -1 && errno == EINVAL)

+	{

+	  /* Some signal numbers in the range are invalid.  E.g.,

+	     signals 32 and 33 on GNU/Linux.  */

+	  fprintf (out, "invalid");

+	}

+      else if (res == -1)

+	{

+	  perror_and_exit ("sigaction");

+	}

+      else

+	{

+	  int m;

+

+	  fprintf (out, "sigaction={sa_handler=", i);

+

+	  if (oldact.sa_handler == SIG_DFL)

+	    fprintf (out, "SIG_DFL");

+	  else if (oldact.sa_handler == SIG_IGN)

+	    fprintf (out, "SIG_IGN");

+	  else

+	    abort ();

+

+	  fprintf (out, ", sa_mask=");

+	  for (m = 1; m < NSIG; m++)

+	    fprintf (out, "%c", sigismember (&oldact.sa_mask, m) ? '1' : '0');

+

+	  fprintf (out, ", sa_flags=%d", oldact.sa_flags);

+

+	  fprintf (out, "}, masked=%d", sigismember (&sigset, i));

+	}

+      fprintf (out, "\n");

+    }

+

+  if (out != stdout)

+    fclose (out);

+

+  return 0;

+}

Index: gdb-7.6.1/gdb/testsuite/gdb.base/signals-state-child.exp

===================================================================

--- /dev/null	1970-01-01 00:00:00.000000000 +0000

+++ gdb-7.6.1/gdb/testsuite/gdb.base/signals-state-child.exp	2017-11-03 19:22:11.458021250 +0100

@@ -0,0 +1,82 @@

+# Copyright 2016 Free Software Foundation, Inc.

+

+# This program is free software; you can redistribute it and/or modify

+# it under the terms of the GNU General Public License as published by

+# the Free Software Foundation; either version 3 of the License, or

+# (at your option) any later version.

+#

+# This program 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 General Public License for more details.

+#

+# You should have received a copy of the GNU General Public License

+# along with this program.  If not, see <http://www.gnu.org/licenses/>.

+

+# Test that gdb's (or gdbserver's) own signal handling does not

+# interfere with the signal actions (dispositions, etc.) and mask

+# their spawned children inherit.

+#

+# - If gdb inherits some signal set to SIG_IGN, so should the

+#   inferior, even if gdb itself chooses not to ignore the signal.

+#

+# - If gdb inherits some signal set to SIG_DFL, so should the inferior

+#   even if gdb itself ignores that signal.

+#

+# This requires special support in gdb/gdbserver because the exec

+# family of functions does not reset the signal disposition of signals

+# that are set to SIG_IGN, nor signal masks and flags.

+

+standard_testfile

+

+set gdb_txt [standard_output_file gdb.txt]

+set standalone_txt [standard_output_file standalone.txt]

+remote_exec host "rm -f $gdb_txt"

+remote_exec host "rm -f $standalone_txt"

+

+set options [list debug "additional_flags=-DOUTPUT_TXT=\"$gdb_txt\""]

+if {[build_executable $testfile.exp $testfile $srcfile $options]} {

+    untested $testfile.exp

+    return -1

+}

+

+set options [list debug "additional_flags=-DOUTPUT_TXT=\"$standalone_txt\""]

+if {[build_executable $testfile.exp $testfile-standalone $srcfile $options]} {

+    untested $testfile.exp

+    return -1

+}

+

+# Run the program directly, and dump its initial signal actions and

+# mask in "standalone.txt".

+

+# Use remote_spawn instead of remote_exec, like how we spawn gdb.

+# This is in order to take the same code code paths in dejagnu

+# compared to when running the program through gdb.  E.g., because

+# local_exec uses -ignore SIGHUP, while remote_spawn does not, if we

+# used remote_exec, the test program would start with SIGHUP ignored

+# when run standalone, but not when run through gdb.

+set res [remote_spawn host "$binfile-standalone"]

+if { $res < 0 || $res == "" } {

+    untested "spawning $binfile-standalone failed"

+    return 1

+} else {

+    pass "collect standalone signals state"

+}

+remote_close host

+

+# Now run the program through gdb, and dump its initial signal actions

+# and mask in "gdb.txt".

+

+clean_restart $binfile

+

+if { ! [ runto_main ] } then {

+    untested $testfile.exp

+    return -1

+}

+

+gdb_continue_to_end "collect signals state under gdb"

+

+# Diff the .txt files.  They should be identical.

+gdb_test "shell diff -s $standalone_txt $gdb_txt" \

+    "Files .* are identical.*" \

+    "signals states are identical"

Index: gdb-7.6.1/gdb/testsuite/gdb.gdb/selftest.exp

===================================================================

--- gdb-7.6.1.orig/gdb/testsuite/gdb.gdb/selftest.exp	2017-11-03 19:22:06.904988012 +0100

+++ gdb-7.6.1/gdb/testsuite/gdb.gdb/selftest.exp	2017-11-03 19:22:11.458021250 +0100

@@ -158,6 +158,10 @@

 		set description "next over bfd_init"

 		set command "next"

 	    }

+	    -re ".*save_original_signals_state ..;.*$gdb_prompt $" {

+		set description "next over save_original_signals_state"

+		set command "next"

+	    }

 	    -re ".*VEC_cleanup .cmdarg_s.*$gdb_prompt $" {

 		set description "next over cmdarg_s VEC_cleanup"

 		set command "next"

Index: gdb-7.6.1/gdb/configure.ac

===================================================================

--- gdb-7.6.1.orig/gdb/configure.ac	2017-11-03 19:22:08.164997210 +0100

+++ gdb-7.6.1/gdb/configure.ac	2017-11-03 19:22:11.459021257 +0100

@@ -1365,7 +1365,7 @@

 		sbrk setpgid setpgrp setsid \

 		sigaction sigprocmask sigsetmask socketpair syscall \

 		ttrace wborder wresize setlocale iconvlist libiconvlist btowc \

-		setrlimit getrlimit posix_madvise waitpid lstat])

+		setrlimit getrlimit posix_madvise waitpid lstat sigaction])

 AM_LANGINFO_CODESET

 # Check the return and argument types of ptrace.  No canned test for

Index: gdb-7.6.1/gdb/gdbserver/configure.ac

===================================================================

--- gdb-7.6.1.orig/gdb/gdbserver/configure.ac	2017-11-03 19:22:10.366013278 +0100

+++ gdb-7.6.1/gdb/gdbserver/configure.ac	2017-11-03 19:22:11.459021257 +0100

@@ -70,7 +70,7 @@

 		 sys/ioctl.h netinet/in.h sys/socket.h netdb.h dnl

 		 netinet/tcp.h arpa/inet.h sys/wait.h wait.h sys/un.h dnl

 		 linux/perf_event.h)

-AC_CHECK_FUNCS(pread pwrite pread64 readlink setns)

+AC_CHECK_FUNCS(pread pwrite pread64 readlink setns sigaction)

 AC_REPLACE_FUNCS(vasprintf vsnprintf)

 # Check for UST