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* [Bug middle-end/28096] fdlibm/strtod.c miscompiled at -O2
       [not found] <bug-28096-12856@http.gcc.gnu.org/bugzilla/>
@ 2006-09-11 17:46 ` pinskia at gcc dot gnu dot org
  2006-09-11 17:49 ` tromey at gcc dot gnu dot org
                   ` (15 subsequent siblings)
  16 siblings, 0 replies; 17+ messages in thread
From: pinskia at gcc dot gnu dot org @ 2006-09-11 17:46 UTC (permalink / raw)
  To: gcc-bugs



-- 

pinskia at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |gcc-bugs at gcc dot gnu dot
                   |                            |org


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=28096


^ permalink raw reply	[flat|nested] 17+ messages in thread

* [Bug middle-end/28096] fdlibm/strtod.c miscompiled at -O2
       [not found] <bug-28096-12856@http.gcc.gnu.org/bugzilla/>
  2006-09-11 17:46 ` [Bug middle-end/28096] fdlibm/strtod.c miscompiled at -O2 pinskia at gcc dot gnu dot org
@ 2006-09-11 17:49 ` tromey at gcc dot gnu dot org
  2006-09-11 18:01 ` tromey at gcc dot gnu dot org
                   ` (14 subsequent siblings)
  16 siblings, 0 replies; 17+ messages in thread
From: tromey at gcc dot gnu dot org @ 2006-09-11 17:49 UTC (permalink / raw)
  To: gcc-bugs



------- Comment #9 from tromey at gcc dot gnu dot org  2006-09-11 17:49 -------
Created an attachment (id=12225)
 --> (http://gcc.gnu.org/bugzilla/attachment.cgi?id=12225&action=view)
preprocessed source

Added a self-contained .i file

Compile with -O2 => fails
Compile with -g => works


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=28096


^ permalink raw reply	[flat|nested] 17+ messages in thread

* [Bug middle-end/28096] fdlibm/strtod.c miscompiled at -O2
       [not found] <bug-28096-12856@http.gcc.gnu.org/bugzilla/>
  2006-09-11 17:46 ` [Bug middle-end/28096] fdlibm/strtod.c miscompiled at -O2 pinskia at gcc dot gnu dot org
  2006-09-11 17:49 ` tromey at gcc dot gnu dot org
@ 2006-09-11 18:01 ` tromey at gcc dot gnu dot org
  2006-09-11 18:06 ` tromey at gcc dot gnu dot org
                   ` (13 subsequent siblings)
  16 siblings, 0 replies; 17+ messages in thread
From: tromey at gcc dot gnu dot org @ 2006-09-11 18:01 UTC (permalink / raw)
  To: gcc-bugs



------- Comment #10 from tromey at gcc dot gnu dot org  2006-09-11 18:01 -------
Created an attachment (id=12226)
 --> (http://gcc.gnu.org/bugzilla/attachment.cgi?id=12226&action=view)
valgrind report


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=28096


^ permalink raw reply	[flat|nested] 17+ messages in thread

* [Bug middle-end/28096] fdlibm/strtod.c miscompiled at -O2
       [not found] <bug-28096-12856@http.gcc.gnu.org/bugzilla/>
                   ` (2 preceding siblings ...)
  2006-09-11 18:01 ` tromey at gcc dot gnu dot org
@ 2006-09-11 18:06 ` tromey at gcc dot gnu dot org
  2006-09-11 18:18 ` [Bug rtl-optimization/28096] " pinskia at gcc dot gnu dot org
                   ` (12 subsequent siblings)
  16 siblings, 0 replies; 17+ messages in thread
From: tromey at gcc dot gnu dot org @ 2006-09-11 18:06 UTC (permalink / raw)
  To: gcc-bugs



------- Comment #11 from tromey at gcc dot gnu dot org  2006-09-11 18:06 -------
I compiled with -O1 and ran valgrind; the results were clean.


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=28096


^ permalink raw reply	[flat|nested] 17+ messages in thread

* [Bug rtl-optimization/28096] fdlibm/strtod.c miscompiled at -O2
       [not found] <bug-28096-12856@http.gcc.gnu.org/bugzilla/>
                   ` (3 preceding siblings ...)
  2006-09-11 18:06 ` tromey at gcc dot gnu dot org
@ 2006-09-11 18:18 ` pinskia at gcc dot gnu dot org
  2006-09-11 19:48 ` dannysmith at users dot sourceforge dot net
                   ` (11 subsequent siblings)
  16 siblings, 0 replies; 17+ messages in thread
From: pinskia at gcc dot gnu dot org @ 2006-09-11 18:18 UTC (permalink / raw)
  To: gcc-bugs



------- Comment #12 from pinskia at gcc dot gnu dot org  2006-09-11 18:18 -------
-O2 -fno-gcse works.


-- 

pinskia at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
          Component|middle-end                  |rtl-optimization


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=28096


^ permalink raw reply	[flat|nested] 17+ messages in thread

* [Bug rtl-optimization/28096] fdlibm/strtod.c miscompiled at -O2
       [not found] <bug-28096-12856@http.gcc.gnu.org/bugzilla/>
                   ` (4 preceding siblings ...)
  2006-09-11 18:18 ` [Bug rtl-optimization/28096] " pinskia at gcc dot gnu dot org
@ 2006-09-11 19:48 ` dannysmith at users dot sourceforge dot net
  2006-09-13  8:32 ` ebotcazou at gcc dot gnu dot org
                   ` (10 subsequent siblings)
  16 siblings, 0 replies; 17+ messages in thread
From: dannysmith at users dot sourceforge dot net @ 2006-09-11 19:48 UTC (permalink / raw)
  To: gcc-bugs



------- Comment #13 from dannysmith at users dot sourceforge dot net  2006-09-11 19:47 -------
In my sources for David Gay's gdtoa implemntation it say this:
/* On a machine with IEEE extended-precision registers, it is
 * necessary to specify double-precision (53-bit) rounding precision
 * before invoking strtod or dtoa.  If the machine uses (the equivalent
 * of) Intel 80x87 arithmetic, the call
 *      _control87(PC_53, MCW_PC);
 * does this with many compilers.  Whether this or another call is
 * appropriate depends on the compiler; for this to work, it may be
 * necessary to #include "float.h" or another system-dependent header
 * file.
 */


There is a variant of strtod in the gdtoa file strtodnrp.c:
/* This is a variant of strtod that works on Intel ia32 systems */
/* with the default extended-precision arithmetic -- it does not */
/* require setting the precision control to 53 bits.  */


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=28096


^ permalink raw reply	[flat|nested] 17+ messages in thread

* [Bug rtl-optimization/28096] fdlibm/strtod.c miscompiled at -O2
       [not found] <bug-28096-12856@http.gcc.gnu.org/bugzilla/>
                   ` (5 preceding siblings ...)
  2006-09-11 19:48 ` dannysmith at users dot sourceforge dot net
@ 2006-09-13  8:32 ` ebotcazou at gcc dot gnu dot org
  2006-09-14  8:27 ` aph at gcc dot gnu dot org
                   ` (9 subsequent siblings)
  16 siblings, 0 replies; 17+ messages in thread
From: ebotcazou at gcc dot gnu dot org @ 2006-09-13  8:32 UTC (permalink / raw)
  To: gcc-bugs



------- Comment #14 from ebotcazou at gcc dot gnu dot org  2006-09-13 08:32 -------
Please indicate whether it's a regression from earlier versions of GCC.


-- 

ebotcazou at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |ebotcazou at gcc dot gnu dot
                   |                            |org


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=28096


^ permalink raw reply	[flat|nested] 17+ messages in thread

* [Bug rtl-optimization/28096] fdlibm/strtod.c miscompiled at -O2
       [not found] <bug-28096-12856@http.gcc.gnu.org/bugzilla/>
                   ` (6 preceding siblings ...)
  2006-09-13  8:32 ` ebotcazou at gcc dot gnu dot org
@ 2006-09-14  8:27 ` aph at gcc dot gnu dot org
  2006-09-20 16:57 ` tromey at gcc dot gnu dot org
                   ` (8 subsequent siblings)
  16 siblings, 0 replies; 17+ messages in thread
From: aph at gcc dot gnu dot org @ 2006-09-14  8:27 UTC (permalink / raw)
  To: gcc-bugs



------- Comment #15 from aph at gcc dot gnu dot org  2006-09-14 08:27 -------
I don't think this bug has anything to do with excess precision.  Valgrind
shows that, when compiled at -O2, we are reading from uninitialized memory.


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=28096


^ permalink raw reply	[flat|nested] 17+ messages in thread

* [Bug rtl-optimization/28096] fdlibm/strtod.c miscompiled at -O2
       [not found] <bug-28096-12856@http.gcc.gnu.org/bugzilla/>
                   ` (7 preceding siblings ...)
  2006-09-14  8:27 ` aph at gcc dot gnu dot org
@ 2006-09-20 16:57 ` tromey at gcc dot gnu dot org
  2006-09-20 17:38 ` [Bug rtl-optimization/28096] [4.2 regression] " ebotcazou at gcc dot gnu dot org
                   ` (7 subsequent siblings)
  16 siblings, 0 replies; 17+ messages in thread
From: tromey at gcc dot gnu dot org @ 2006-09-20 16:57 UTC (permalink / raw)
  To: gcc-bugs



------- Comment #16 from tromey at gcc dot gnu dot org  2006-09-20 16:57 -------
Yes, this is a regression.
It works fine with -O2 with my system compiler (FC5 gcc, based on gcc 4.1).
It also works fine with -O2 using my gcc 4.1 build.
It fails with svn head.


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=28096


^ permalink raw reply	[flat|nested] 17+ messages in thread

* [Bug rtl-optimization/28096] [4.2 regression] fdlibm/strtod.c miscompiled at -O2
       [not found] <bug-28096-12856@http.gcc.gnu.org/bugzilla/>
                   ` (8 preceding siblings ...)
  2006-09-20 16:57 ` tromey at gcc dot gnu dot org
@ 2006-09-20 17:38 ` ebotcazou at gcc dot gnu dot org
  2006-09-20 17:39 ` ebotcazou at gcc dot gnu dot org
                   ` (6 subsequent siblings)
  16 siblings, 0 replies; 17+ messages in thread
From: ebotcazou at gcc dot gnu dot org @ 2006-09-20 17:38 UTC (permalink / raw)
  To: gcc-bugs



------- Comment #17 from ebotcazou at gcc dot gnu dot org  2006-09-20 17:38 -------
> Yes, this is a regression.
> It works fine with -O2 with my system compiler (FC5 gcc, based on gcc 4.1).
> It also works fine with -O2 using my gcc 4.1 build.
> It fails with svn head.

Thanks for the info.


-- 

ebotcazou at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
            Summary|fdlibm/strtod.c miscompiled |[4.2 regression]
                   |at -O2                      |fdlibm/strtod.c miscompiled
                   |                            |at -O2
   Target Milestone|---                         |4.2.0


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=28096


^ permalink raw reply	[flat|nested] 17+ messages in thread

* [Bug rtl-optimization/28096] [4.2 regression] fdlibm/strtod.c miscompiled at -O2
       [not found] <bug-28096-12856@http.gcc.gnu.org/bugzilla/>
                   ` (9 preceding siblings ...)
  2006-09-20 17:38 ` [Bug rtl-optimization/28096] [4.2 regression] " ebotcazou at gcc dot gnu dot org
@ 2006-09-20 17:39 ` ebotcazou at gcc dot gnu dot org
  2006-09-20 22:10 ` mmitchel at gcc dot gnu dot org
                   ` (5 subsequent siblings)
  16 siblings, 0 replies; 17+ messages in thread
From: ebotcazou at gcc dot gnu dot org @ 2006-09-20 17:39 UTC (permalink / raw)
  To: gcc-bugs



------- Comment #18 from ebotcazou at gcc dot gnu dot org  2006-09-20 17:39 -------
Investigating.


-- 

ebotcazou at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
         AssignedTo|unassigned at gcc dot gnu   |ebotcazou at gcc dot gnu dot
                   |dot org                     |org
             Status|NEW                         |ASSIGNED
   Last reconfirmed|2006-09-10 09:03:40         |2006-09-20 17:39:16
               date|                            |


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=28096


^ permalink raw reply	[flat|nested] 17+ messages in thread

* [Bug rtl-optimization/28096] [4.2 regression] fdlibm/strtod.c miscompiled at -O2
       [not found] <bug-28096-12856@http.gcc.gnu.org/bugzilla/>
                   ` (10 preceding siblings ...)
  2006-09-20 17:39 ` ebotcazou at gcc dot gnu dot org
@ 2006-09-20 22:10 ` mmitchel at gcc dot gnu dot org
  2006-09-29 20:40 ` ebotcazou at gcc dot gnu dot org
                   ` (4 subsequent siblings)
  16 siblings, 0 replies; 17+ messages in thread
From: mmitchel at gcc dot gnu dot org @ 2006-09-20 22:10 UTC (permalink / raw)
  To: gcc-bugs



-- 

mmitchel at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
           Priority|P3                          |P1


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=28096


^ permalink raw reply	[flat|nested] 17+ messages in thread

* [Bug rtl-optimization/28096] [4.2 regression] fdlibm/strtod.c miscompiled at -O2
       [not found] <bug-28096-12856@http.gcc.gnu.org/bugzilla/>
                   ` (11 preceding siblings ...)
  2006-09-20 22:10 ` mmitchel at gcc dot gnu dot org
@ 2006-09-29 20:40 ` ebotcazou at gcc dot gnu dot org
  2006-09-30  8:30 ` pinskia at gcc dot gnu dot org
                   ` (3 subsequent siblings)
  16 siblings, 0 replies; 17+ messages in thread
From: ebotcazou at gcc dot gnu dot org @ 2006-09-29 20:40 UTC (permalink / raw)
  To: gcc-bugs



------- Comment #19 from ebotcazou at gcc dot gnu dot org  2006-09-29 20:40 -------
> I don't think this bug has anything to do with excess precision.  Valgrind
> shows that, when compiled at -O2, we are reading from uninitialized memory.

Confirmed:

        andl    -144(%ebp), %ebx  <--- bogus value in %ebx
        movl    %eax, -144(%ebp)

Swap the lines and all works fine.


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=28096


^ permalink raw reply	[flat|nested] 17+ messages in thread

* [Bug rtl-optimization/28096] [4.2 regression] fdlibm/strtod.c miscompiled at -O2
       [not found] <bug-28096-12856@http.gcc.gnu.org/bugzilla/>
                   ` (12 preceding siblings ...)
  2006-09-29 20:40 ` ebotcazou at gcc dot gnu dot org
@ 2006-09-30  8:30 ` pinskia at gcc dot gnu dot org
  2006-09-30  8:50 ` ebotcazou at gcc dot gnu dot org
                   ` (2 subsequent siblings)
  16 siblings, 0 replies; 17+ messages in thread
From: pinskia at gcc dot gnu dot org @ 2006-09-30  8:30 UTC (permalink / raw)
  To: gcc-bugs



------- Comment #20 from pinskia at gcc dot gnu dot org  2006-09-30 08:29 -------
(In reply to comment #19)
> Confirmed:
> 
>         andl    -144(%ebp), %ebx  <--- bogus value in %ebx
>         movl    %eax, -144(%ebp)

This smells like an aliasing issue.


-- 

pinskia at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
           Keywords|                            |alias


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=28096


^ permalink raw reply	[flat|nested] 17+ messages in thread

* [Bug rtl-optimization/28096] [4.2 regression] fdlibm/strtod.c miscompiled at -O2
       [not found] <bug-28096-12856@http.gcc.gnu.org/bugzilla/>
                   ` (13 preceding siblings ...)
  2006-09-30  8:30 ` pinskia at gcc dot gnu dot org
@ 2006-09-30  8:50 ` ebotcazou at gcc dot gnu dot org
  2006-09-30 13:31 ` ebotcazou at gcc dot gnu dot org
  2006-09-30 13:35 ` ebotcazou at gcc dot gnu dot org
  16 siblings, 0 replies; 17+ messages in thread
From: ebotcazou at gcc dot gnu dot org @ 2006-09-30  8:50 UTC (permalink / raw)
  To: gcc-bugs



------- Comment #21 from ebotcazou at gcc dot gnu dot org  2006-09-30 08:50 -------
> This smells like an aliasing issue.

But it's not, it's if-conversion.


-- 

ebotcazou at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
           Keywords|alias                       |


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=28096


^ permalink raw reply	[flat|nested] 17+ messages in thread

* [Bug rtl-optimization/28096] [4.2 regression] fdlibm/strtod.c miscompiled at -O2
       [not found] <bug-28096-12856@http.gcc.gnu.org/bugzilla/>
                   ` (14 preceding siblings ...)
  2006-09-30  8:50 ` ebotcazou at gcc dot gnu dot org
@ 2006-09-30 13:31 ` ebotcazou at gcc dot gnu dot org
  2006-09-30 13:35 ` ebotcazou at gcc dot gnu dot org
  16 siblings, 0 replies; 17+ messages in thread
From: ebotcazou at gcc dot gnu dot org @ 2006-09-30 13:31 UTC (permalink / raw)
  To: gcc-bugs



------- Comment #22 from ebotcazou at gcc dot gnu dot org  2006-09-30 13:31 -------
Subject: Bug 28096

Author: ebotcazou
Date: Sat Sep 30 13:31:29 2006
New Revision: 117331

URL: http://gcc.gnu.org/viewcvs?root=gcc&view=rev&rev=117331
Log:
        PR rtl-optimization/28096
        * ifcvt.c (check_cond_move_block): Return FALSE if the source of an
        assignment has already been used as a destination earlier in the
        block.


Added:
    trunk/gcc/testsuite/gcc.c-torture/execute/20060930-1.c
Modified:
    trunk/gcc/ChangeLog
    trunk/gcc/ifcvt.c
    trunk/gcc/testsuite/ChangeLog


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=28096


^ permalink raw reply	[flat|nested] 17+ messages in thread

* [Bug rtl-optimization/28096] [4.2 regression] fdlibm/strtod.c miscompiled at -O2
       [not found] <bug-28096-12856@http.gcc.gnu.org/bugzilla/>
                   ` (15 preceding siblings ...)
  2006-09-30 13:31 ` ebotcazou at gcc dot gnu dot org
@ 2006-09-30 13:35 ` ebotcazou at gcc dot gnu dot org
  16 siblings, 0 replies; 17+ messages in thread
From: ebotcazou at gcc dot gnu dot org @ 2006-09-30 13:35 UTC (permalink / raw)
  To: gcc-bugs



------- Comment #23 from ebotcazou at gcc dot gnu dot org  2006-09-30 13:35 -------
Should work now.


-- 

ebotcazou at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                URL|                            |http://gcc.gnu.org/ml/gcc-
                   |                            |patches/2006-
                   |                            |09/msg01398.html
             Status|ASSIGNED                    |RESOLVED
         Resolution|                            |FIXED


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=28096


^ permalink raw reply	[flat|nested] 17+ messages in thread

end of thread, other threads:[~2006-09-30 13:35 UTC | newest]

Thread overview: 17+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
     [not found] <bug-28096-12856@http.gcc.gnu.org/bugzilla/>
2006-09-11 17:46 ` [Bug middle-end/28096] fdlibm/strtod.c miscompiled at -O2 pinskia at gcc dot gnu dot org
2006-09-11 17:49 ` tromey at gcc dot gnu dot org
2006-09-11 18:01 ` tromey at gcc dot gnu dot org
2006-09-11 18:06 ` tromey at gcc dot gnu dot org
2006-09-11 18:18 ` [Bug rtl-optimization/28096] " pinskia at gcc dot gnu dot org
2006-09-11 19:48 ` dannysmith at users dot sourceforge dot net
2006-09-13  8:32 ` ebotcazou at gcc dot gnu dot org
2006-09-14  8:27 ` aph at gcc dot gnu dot org
2006-09-20 16:57 ` tromey at gcc dot gnu dot org
2006-09-20 17:38 ` [Bug rtl-optimization/28096] [4.2 regression] " ebotcazou at gcc dot gnu dot org
2006-09-20 17:39 ` ebotcazou at gcc dot gnu dot org
2006-09-20 22:10 ` mmitchel at gcc dot gnu dot org
2006-09-29 20:40 ` ebotcazou at gcc dot gnu dot org
2006-09-30  8:30 ` pinskia at gcc dot gnu dot org
2006-09-30  8:50 ` ebotcazou at gcc dot gnu dot org
2006-09-30 13:31 ` ebotcazou at gcc dot gnu dot org
2006-09-30 13:35 ` ebotcazou at gcc dot gnu dot org

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