BUG#38817: please make mtr analyze crashes better

  return unless -f $core_name;

  my $dir = tempdir( CLEANUP => 1 );

  my ($tmp, $tmp_name) = tempfile( DIR => $dir );

  # Find out name of binary that generated core

  `gdb -c '$core_name' --batch 2>&1` =~

    /Core was generated by `([^\s\'\`]+)/;

  my $binary= $1 or return;

  print "Core generated by '$binary'\n";

  # Create tempfile containing gdb commands

  my ($tmp, $tmp_name) = tempfile();

  print $tmp

    "bt\n",

    "thread apply all bt\n",

    "quit\n";

  close $tmp or die "Error closing $tmp_name: $!";

  # Find out name of binary that generated core

  my $list= `gdb -c $core_name -x $tmp_name -batch 2>&1`

    or return;

  my $binary;

  foreach my $line (split('\n', $list))

  {

    $binary= $1

      if ($line =~ /Core was generated by `(\S+)/);

  }

  return unless $binary;

  print " - core generated by '$binary'\n";

  # Run gdb

  my $gdb_output=

    `gdb '$binary' -c '$core_name' -x '$tmp_name' --batch 2>&1`;

  my $list= `gdb $binary -c $core_name -x $tmp_name -batch 2>&1`

    or return;

  unlink $tmp_name or die "Error removing $tmp_name: $!";

  print $list, "\n";

  return unless $gdb_output;

  print <<EOF, $gdb_output, "\n";

Output from gdb follows. The first stack trace is from the failing thread.

The following stack traces are from all threads (so the failing one is

duplicated).

EOF

  return 1;

}