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Pedro Alves 3e74e146f2 Linux: No need to set ptrace event options in fork/clone children.
Oleg Nesterov told me that the Linux kernel copies the parent's ptrace
options to fork/clone children, so there's no need for GDB to do that
manually.

I was actually a bit surprised, since I thought the ptracer had to
always set the ptrace options itself, and GDB is indeed calling
PTRACE_SETOPTIONS for each new fork child, if it'll stay attached.

Looking at the history of that code, I found that is was actually I
who added that set-ptrace-options-in-children bit, back in
http://sourceware.org/ml/gdb-patches/2009-05/msg00656.html.  But,
honestly, I don't recall why I needed that.  I think I may have just
blindly believed it was necessary.

I then looked back at the history of all the PTRACE_SETOPTIONS code we
have, and found that gdb never did copy the ptrace options before my
patch.  But, when gdbserver learnt to use PTRACE_EVENT_CLONE, at
http://sourceware.org/ml/gdb-patches/2007-10/msg00547.html, it was
made to do 'ptrace (PTRACE_SETOPTIONS, new_pid, 0,
PTRACE_O_TRACECLONE)' for all new clones.  Hmmm.  But, GDB itself
never did that, so it can't really ever have been necessary, I
believe, otherwise GDB should have been doing it too.

(GDBserver doesn't support following forks, and so naturally doesn't
do any PTRACE_SETOPTIONS on fork children.)

So this patch removes the -I believe- unnecessary ptrace syscalls.

Tested on x86_64 Fedora 17, native/gdbserver, and on x86_64 RHEL5
native/gdbserver (Linux 2.6.18, I think a ptrace-on-utrace kernel).
No regressions.

gdb/
2013-03-22  Pedro Alves  <palves@redhat.com>

	* linux-nat.c (linux_child_follow_fork): Don't call
	linux_enable_event_reporting.
	(linux_handle_extended_wait): Don't call
	linux_enable_event_reporting.

gdb/gdbserver/
2013-03-22  Pedro Alves  <palves@redhat.com>

	* linux-low.c (handle_extended_wait): Don't call
	linux_enable_event_reporting.
2013-03-22 14:52:26 +00:00
bfd daily update 2013-03-21 23:00:05 +00:00
binutils * addr2line.c (slurp_symtab): If canonicalization reveals that 2013-03-15 16:25:00 +00:00
config
cpu
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gas gas/ChangeLog: 2013-03-21 18:39:35 +00:00
gdb Linux: No need to set ptrace event options in fork/clone children. 2013-03-22 14:52:26 +00:00
gold * layout.cc (Layout::set_segment_offsets): Accept writable .text 2013-03-21 04:52:55 +00:00
gprof
include * elf32-h8300 (h8_relax_section): Add new relaxation of mov 2013-03-21 16:08:07 +00:00
intl
ld * ld-elf/init0.s: Add alloc attribute to .section directive. 2013-03-22 09:40:06 +00:00
libdecnumber
libiberty merge from gcc 2013-03-17 21:25:53 +00:00
opcodes * include/opcode/tic6x.h: add tic6x_coding_dreg_(msb|lsb) field coding type in 2013-03-20 16:36:34 +00:00
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sim gdb: 2013-03-15 17:53:44 +00:00
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		   README for GNU development tools

This directory contains various GNU compilers, assemblers, linkers, 
debuggers, etc., plus their support routines, definitions, and documentation.

If you are receiving this as part of a GDB release, see the file gdb/README.
If with a binutils release, see binutils/README;  if with a libg++ release,
see libg++/README, etc.  That'll give you info about this
package -- supported targets, how to use it, how to report bugs, etc.

It is now possible to automatically configure and build a variety of
tools with one command.  To build all of the tools contained herein,
run the ``configure'' script here, e.g.:

	./configure 
	make

To install them (by default in /usr/local/bin, /usr/local/lib, etc),
then do:
	make install

(If the configure script can't determine your type of computer, give it
the name as an argument, for instance ``./configure sun4''.  You can
use the script ``config.sub'' to test whether a name is recognized; if
it is, config.sub translates it to a triplet specifying CPU, vendor,
and OS.)

If you have more than one compiler on your system, it is often best to
explicitly set CC in the environment before running configure, and to
also set CC when running make.  For example (assuming sh/bash/ksh):

	CC=gcc ./configure
	make

A similar example using csh:

	setenv CC gcc
	./configure
	make

Much of the code and documentation enclosed is copyright by
the Free Software Foundation, Inc.  See the file COPYING or
COPYING.LIB in the various directories, for a description of the
GNU General Public License terms under which you can copy the files.

REPORTING BUGS: Again, see gdb/README, binutils/README, etc., for info
on where and how to report problems.