Backported r185234 from trunk (r194264 from google/gcc-4_7).

2012-12-03  Ahmad Sharif <asharif@google.com>

	Backport r185231 from trunk.

	2012-03-12  Richard Guenther  <rguenther@suse.de>

	* gthr.h (__GTHREAD_MUTEX_INIT_FUNCTION): Adjust specification.
	* gthr-posix.h (__GTHREAD_MUTEX_INIT_FUNCTION): Define.
	(__gthread_mutex_init_function): New function.
	* gthr-single.h (__GTHREAD_MUTEX_INIT_FUNCTION): Define.

	PR gcov/49484
	* libgcov.c: Include gthr.h.
	(__gcov_flush_mx): New global variable.
	(init_mx, init_mx_once): New functions.
	(__gcov_flush): Protect self with a mutex.
	(__gcov_fork): Re-initialize mutex after forking.
	* unwind-dw2-fde.c: Change condition under which to use
	__GTHREAD_MUTEX_INIT_FUNCTION.

[asharif, 2012-12-06 20:18:02]

Please review this backport needed to enable PGO for Chrome.

[shenhan, 2012-12-06 21:19:17]

On 2012/12/06 20:18:02, asharif wrote:
> Please review this backport needed to enable PGO for Chrome.

I think we shall only change ChangeLog.google-xxx when adding changes to google
branch.

Quote from Diego - 
'Please remember to use ChangeLog.google-xxx when adding ChangeLog entries to
the google branches.'

[asharif, 2012-12-06 21:51:54]

On 2012/12/06 21:19:17, shenhan wrote:
> On 2012/12/06 20:18:02, asharif wrote:
> > Please review this backport needed to enable PGO for Chrome.
> 
> I think we shall only change ChangeLog.google-xxx when adding changes to
google
> branch.
> 
> Quote from Diego - 
> 'Please remember to use ChangeLog.google-xxx when adding ChangeLog entries to
> the google branches.'

I don't think the rule is to *only* update ChangeLog.google*. The rule is to
update ChangeLog, but also update ChangeLog.google*.

In the next patchset I have updated ChangeLog.google-4_7-mobile.

PTAL.

[Diego Novillo, 2012-12-06 22:02:16]

On Thu, Dec 6, 2012 at 4:51 PM,  <asharif@chromium.org> wrote:

> I don't think the rule is to *only* update ChangeLog.google*. The rule
> is to update ChangeLog, but also update ChangeLog.google*.

Just ChangeLog.google*, actually.  When cherry picking revisions from
other branches, it's better not to update ChangeLog.  It's not really
necessary and it will actually cause merge conflicts later.  I'll
clarify the developer notes.


Thanks.  Diego.

[asharif, 2012-12-07 00:29:39]

On 2012/12/06 22:02:16, Diego Novillo wrote:
> On Thu, Dec 6, 2012 at 4:51 PM,  <mailto:asharif@chromium.org> wrote:
> 
> > I don't think the rule is to *only* update ChangeLog.google*. The rule
> > is to update ChangeLog, but also update ChangeLog.google*.
> 
> Just ChangeLog.google*, actually.  When cherry picking revisions from
> other branches, it's better not to update ChangeLog.  It's not really
> necessary and it will actually cause merge conflicts later.  I'll
> clarify the developer notes.
> 
> 
> Thanks.  Diego.

Done.

I have removed the ChangeLog chunk. PTAL.

[shenhan, 2012-12-07 00:33:01]

On 2012/12/07 00:29:39, asharif wrote:
> On 2012/12/06 22:02:16, Diego Novillo wrote:
> > On Thu, Dec 6, 2012 at 4:51 PM,  <mailto:asharif@chromium.org> wrote:
> > 
> > > I don't think the rule is to *only* update ChangeLog.google*. The rule
> > > is to update ChangeLog, but also update ChangeLog.google*.
> > 
> > Just ChangeLog.google*, actually.  When cherry picking revisions from
> > other branches, it's better not to update ChangeLog.  It's not really
> > necessary and it will actually cause merge conflicts later.  I'll
> > clarify the developer notes.
> > 
> > 
> > Thanks.  Diego.
> 
> Done.
> 
> I have removed the ChangeLog chunk. PTAL.

LGTM