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* [Bug lto/47900] New: Missed optimization with LTO
@ 2011-02-26  8:54 d.g.gorbachev at gmail dot com
  2011-02-27 15:14 ` [Bug lto/47900] " rguenth at gcc dot gnu.org
                   ` (3 more replies)
  0 siblings, 4 replies; 5+ messages in thread
From: d.g.gorbachev at gmail dot com @ 2011-02-26  8:54 UTC (permalink / raw)
  To: gcc-bugs

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=47900

           Summary: Missed optimization with LTO
           Product: gcc
           Version: 4.6.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: lto
        AssignedTo: unassigned@gcc.gnu.org
        ReportedBy: d.g.gorbachev@gmail.com


Created attachment 23474
  --> http://gcc.gnu.org/bugzilla/attachment.cgi?id=23474
Testcase


^ permalink raw reply	[flat|nested] 5+ messages in thread
* [Bug lto/47900] Missed optimization with LTO
  2011-02-26  8:54 [Bug lto/47900] New: Missed optimization with LTO d.g.gorbachev at gmail dot com
@ 2011-02-27 15:14 ` rguenth at gcc dot gnu.org
  2011-02-27 20:03 ` d.g.gorbachev at gmail dot com
                   ` (2 subsequent siblings)
  3 siblings, 0 replies; 5+ messages in thread
From: rguenth at gcc dot gnu.org @ 2011-02-27 15:14 UTC (permalink / raw)
  To: gcc-bugs

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=47900

Richard Guenther <rguenth at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |WAITING
   Last reconfirmed|                            |2011.02.27 15:13:22
     Ever Confirmed|0                           |1

--- Comment #1 from Richard Guenther <rguenth at gcc dot gnu.org> 2011-02-27 15:13:22 UTC ---
I fail to see what the missed optimization is, can you try to explain?


^ permalink raw reply	[flat|nested] 5+ messages in thread
* [Bug lto/47900] Missed optimization with LTO
  2011-02-26  8:54 [Bug lto/47900] New: Missed optimization with LTO d.g.gorbachev at gmail dot com
  2011-02-27 15:14 ` [Bug lto/47900] " rguenth at gcc dot gnu.org
@ 2011-02-27 20:03 ` d.g.gorbachev at gmail dot com
  2011-02-27 20:09 ` rguenth at gcc dot gnu.org
  2013-02-07  0:13 ` d.g.gorbachev at gmail dot com
  3 siblings, 0 replies; 5+ messages in thread
From: d.g.gorbachev at gmail dot com @ 2011-02-27 20:03 UTC (permalink / raw)
  To: gcc-bugs

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=47900

--- Comment #2 from Dmitry Gorbachev <d.g.gorbachev at gmail dot com> 2011-02-27 19:57:01 UTC ---
A null pointer check (... && ! &p->i) is not eliminated, notwithstanding the
fact that the pointer has been dereferenced. If it is not null, bar is not
called; otherwise, there is an undefined behavior, and bar is not called.

Or is it too an unimportant problem?

(It's interesting, after changing S_ptr p to struct S *p, the non-LTO build
also fails with "undefined reference to `bar'".)


^ permalink raw reply	[flat|nested] 5+ messages in thread
* [Bug lto/47900] Missed optimization with LTO
  2011-02-26  8:54 [Bug lto/47900] New: Missed optimization with LTO d.g.gorbachev at gmail dot com
  2011-02-27 15:14 ` [Bug lto/47900] " rguenth at gcc dot gnu.org
  2011-02-27 20:03 ` d.g.gorbachev at gmail dot com
@ 2011-02-27 20:09 ` rguenth at gcc dot gnu.org
  2013-02-07  0:13 ` d.g.gorbachev at gmail dot com
  3 siblings, 0 replies; 5+ messages in thread
From: rguenth at gcc dot gnu.org @ 2011-02-27 20:09 UTC (permalink / raw)
  To: gcc-bugs

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=47900

Richard Guenther <rguenth at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|WAITING                     |NEW

--- Comment #3 from Richard Guenther <rguenth at gcc dot gnu.org> 2011-02-27 20:03:05 UTC ---
Hm, ok.  It's surely worth investigating.


^ permalink raw reply	[flat|nested] 5+ messages in thread
* [Bug lto/47900] Missed optimization with LTO
  2011-02-26  8:54 [Bug lto/47900] New: Missed optimization with LTO d.g.gorbachev at gmail dot com
                   ` (2 preceding siblings ...)
  2011-02-27 20:09 ` rguenth at gcc dot gnu.org
@ 2013-02-07  0:13 ` d.g.gorbachev at gmail dot com
  3 siblings, 0 replies; 5+ messages in thread
From: d.g.gorbachev at gmail dot com @ 2013-02-07  0:13 UTC (permalink / raw)
  To: gcc-bugs


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=47900

Dmitry Gorbachev <d.g.gorbachev at gmail dot com> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|NEW                         |RESOLVED
         Resolution|                            |WORKSFORME

--- Comment #4 from Dmitry Gorbachev <d.g.gorbachev at gmail dot com> 2013-02-07 00:13:03 UTC ---
I can't reproduce it with GCC 4.6.4, 4.7.3, 4.8.0.


^ permalink raw reply	[flat|nested] 5+ messages in thread
end of thread, other threads:[~2013-02-07  0:13 UTC | newest]

Thread overview: 5+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2011-02-26  8:54 [Bug lto/47900] New: Missed optimization with LTO d.g.gorbachev at gmail dot com
2011-02-27 15:14 ` [Bug lto/47900] " rguenth at gcc dot gnu.org
2011-02-27 20:03 ` d.g.gorbachev at gmail dot com
2011-02-27 20:09 ` rguenth at gcc dot gnu.org
2013-02-07  0:13 ` d.g.gorbachev at gmail dot com

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