[Bug c/36817] New: internal compiler error: in compare_values_warnv

[Bug c/36817] New: internal compiler error: in compare_values_warnv

[hans dot buchmann at fhso dot ch]

Compiling the code bug.cc:

 void xxx()
 {
  unsigned*p=0;
  for(unsigned i=0;i<4;++i)
  {
   *p++=0;
  }
  for(unsigned i=0;i<4;++i) 
  {
   *p++=0;
  }
 }

with the command:

 /home/buchmann/devel//eo3s//tc/bin/arm-elf-gcc \
 -O2 -Wall \
 -c -o bug.o bug.cc

results in:

  bug.cc: In function 'void xxx()':
  bug.cc:1: internal compiler error: in compare_values_warnv, at tree-vrp.c:768
  Please submit a full bug report,
  with preprocessed source if appropriate.
  See <http://gcc.gnu.org/bugs.html> for instructions.

arm-elf-gcc -v:

  Using built-in specs.
  Target: arm-elf
  Configured with: /home/buchmann/devel/gcc/dist/gcc-4.3.1/configure -v \
  --prefix=/home/buchmann/devel/gcc/target/arm \
  --target=arm-elf \
  --enable-languages=c,c++ \
  --disable-threads \
  --disable-shared \
  --disable-multilib \
  --disable-__cxa_atexit \
  --with-as=/home/buchmann/devel/gcc/target/arm/arm-elf/bin/as \
  --with-ld=/home/buchmann/devel/gcc/target/arm/arm-elf/bin/ld \
  --with-float=soft \
  --with-newlib \
  --without-headers \
  --with-mpfr=/home/buchmann/devel/gcc/target/arm/../infrastructure/
  Thread model: single
  gcc version 4.3.1 (GCC)

Best regards 

Hans Buchmann


-- 
           Summary: internal compiler error: in compare_values_warnv
           Product: gcc
           Version: 4.3.1
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: c
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: hans dot buchmann at fhso dot ch
 GCC build triplet: i686-pc-linux-gnu
  GCC host triplet: i686-pc-linux-gnu
GCC target triplet: arm-elf


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=36817

[Bug middle-end/36817] [4.3 Regression] internal compiler error: in compare_values_warnv

[pinskia at gcc dot gnu dot org]

-- 

pinskia at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |pinskia at gcc dot gnu dot
                   |                            |org
           Severity|normal                      |blocker
          Component|c                           |middle-end
           Keywords|                            |ice-on-valid-code
      Known to fail|                            |4.2.0
      Known to work|                            |4.4.0
            Summary|internal compiler error: in |[4.3 Regression] internal
                   |compare_values_warnv        |compiler error: in
                   |                            |compare_values_warnv
   Target Milestone|---                         |4.3.2


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=36817

[Bug middle-end/36817] [4.3 Regression] internal compiler error: in compare_values_warnv

[jakub at gcc dot gnu dot org]

------- Comment #1 from jakub at gcc dot gnu dot org  2008-08-11 19:28 -------
This is target independent, reproduced on x86_64-linux and ppc-linux as well.


-- 

jakub at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
  GCC build triplet|i686-pc-linux-gnu           |
   GCC host triplet|i686-pc-linux-gnu           |
 GCC target triplet|arm-elf                     |


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=36817

[Bug middle-end/36817] [4.3 Regression] internal compiler error: in compare_values_warnv

[rguenth at gcc dot gnu dot org]

------- Comment #2 from rguenth at gcc dot gnu dot org  2008-08-13 09:59 -------
The failure is recent, it doesn't occur with gcc-4.3 (SUSE Linux) 4.3.2
20080806 (prerelease) [gcc-4_3-branch revision 138797].


-- 

rguenth at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |rguenth at gcc dot gnu dot
                   |                            |org
             Status|UNCONFIRMED                 |NEW
     Ever Confirmed|0                           |1
   Last reconfirmed|0000-00-00 00:00:00         |2008-08-13 09:59:49
               date|                            |


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=36817

[Bug middle-end/36817] [4.3 Regression] internal compiler error: in compare_values_warnv

[jakub at gcc dot gnu dot org]

------- Comment #3 from jakub at gcc dot gnu dot org  2008-08-14 08:33 -------
I can reproduce it with 4.3.2 20080612 or even 4.3.1 20080428.  Perhaps you
have some tree-vrp.c patches in?


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=36817

[Bug middle-end/36817] [4.3 Regression] internal compiler error: in compare_values_warnv

[rguenther at suse dot de]

------- Comment #4 from rguenther at suse dot de  2008-08-14 08:53 -------
Subject: Re:  [4.3 Regression] internal compiler error:
 in compare_values_warnv

On Thu, 14 Aug 2008, jakub at gcc dot gnu dot org wrote:

> ------- Comment #3 from jakub at gcc dot gnu dot org  2008-08-14 08:33 -------
> I can reproduce it with 4.3.2 20080612 or even 4.3.1 20080428.  Perhaps you
> have some tree-vrp.c patches in?

Hm, I can repoduce it with plain FSF 4.3.0 and 4.3.1 as well.  No
tree-vrp.c patches here, but of course other patches may as well hide
the bug here.

Richard.


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=36817

[Bug middle-end/36817] [4.3 Regression] internal compiler error: in compare_values_warnv

[jsm28 at gcc dot gnu dot org]

-- 

jsm28 at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
           Priority|P3                          |P2


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=36817

[Bug middle-end/36817] [4.3 Regression] internal compiler error: in compare_values_warnv

[cnstar9988 at gmail dot com]

------- Comment #5 from cnstar9988 at gmail dot com  2008-08-21 01:21 -------
ping.....
I can reproduce with gcc 4.3.2 RC1.
It work well on gcc 4.2.4, 4.3.0.

gcc -O2 -Wall -c bug.c
---------------------------------
void xxx()
 {
  unsigned i;
  unsigned*p=0;
  for(i=0;i<4;++i)
  {
   *p++=0;
  }
  for(i=0;i<4;++i)
  {
   *p++=0;
  }
 }


-- 

cnstar9988 at gmail dot com changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |joseph at codesourcery dot
                   |                            |com


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=36817

[Bug middle-end/36817] [4.3 Regression] internal compiler error: in compare_values_warnv

[rguenth at gcc dot gnu dot org]

------- Comment #6 from rguenth at gcc dot gnu dot org  2008-08-21 11:35 -------
Investigating.


-- 

rguenth at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
         AssignedTo|unassigned at gcc dot gnu   |rguenth at gcc dot gnu dot
                   |dot org                     |org
             Status|NEW                         |ASSIGNED
   Last reconfirmed|2008-08-13 09:59:49         |2008-08-21 11:35:49
               date|                            |


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=36817

[Bug middle-end/36817] [4.3 Regression] internal compiler error: in compare_values_warnv

[rguenth at gcc dot gnu dot org]

------- Comment #7 from rguenth at gcc dot gnu dot org  2008-08-21 12:02 -------
I have a patch.


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=36817

[Bug middle-end/36817] [4.3 Regression] internal compiler error: in compare_values_warnv

[joseph at codesourcery dot com]

------- Comment #8 from joseph at codesourcery dot com  2008-08-21 12:05 -------
Subject: Re:  [4.3 Regression] internal compiler error:
 in compare_values_warnv

On Thu, 21 Aug 2008, cnstar9988 at gmail dot com wrote:

> ping.....
> I can reproduce with gcc 4.3.2 RC1.
> It work well on gcc 4.2.4, 4.3.0.

Thanks for the report.  We now have contradictory reports about whether 
this is a regression from previous 4.3 releases or not.  I'll await 
Richard's conclusions (and hopefully patch).


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=36817

[Bug middle-end/36817] [4.3 Regression] internal compiler error: in compare_values_warnv

[rguenth at gcc dot gnu dot org]

------- Comment #9 from rguenth at gcc dot gnu dot org  2008-08-21 12:07 -------
Fails with all of the 4.3 series, works for earlier releases.  The problem is
still latent on the trunk.


-- 

rguenth at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
      Known to fail|4.2.0                       |4.3.0 4.3.1
      Known to work|4.4.0                       |4.2.4 4.4.0


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=36817

[Bug middle-end/36817] [4.3 Regression] internal compiler error: in compare_values_warnv

[cnstar9988 at gmail dot com]

------- Comment #10 from cnstar9988 at gmail dot com  2008-08-21 12:53 -------
I am sorry for wrong test for 4.3.0.

=================================================
I rebuild my gcc 4.3.0 on 2.6.9-42.7AXsmp with gmp 4.2.3 + mpfr 2.3.1.

And make a test again. It works fail.
But the following code well on gcc 4.3.2-RC1. 
=================================================
 void xxx()
 {
  unsigned i;
  unsigned*p=2;  /* 2 is ok, but failed with 0 */
  for(i=0;i<4;++i)
  {
   *p++=0;
  }
  for(i=0;i<4;++i)
  {
   *p++=0;
  }
 }


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=36817

[Bug middle-end/36817] [4.3 Regression] internal compiler error: in compare_values_warnv

[rguenther at suse dot de]

------- Comment #11 from rguenther at suse dot de  2008-08-21 13:48 -------
Subject: [PATCH] Fix PR36817

On Thu, 21 Aug 2008, cnstar9988 at gmail dot com wrote:

> I am sorry for wrong test for 4.3.0.
> 
> =================================================
> I rebuild my gcc 4.3.0 on 2.6.9-42.7AXsmp with gmp 4.2.3 + mpfr 2.3.1.
> 
> And make a test again. It works fail.
> But the following code well on gcc 4.3.2-RC1. 
> =================================================
>  void xxx()
>  {
>   unsigned i;
>   unsigned*p=2;  /* 2 is ok, but failed with 0 */
>   for(i=0;i<4;++i)
>   {
>    *p++=0;
>   }
>   for(i=0;i<4;++i)
>   {
>    *p++=0;
>   }
>  }

The following fix makes it obvious that _only_ pointer(!) induction
variables with zero(!) base are affected - thus I think this can
wait until after 4.3.2.

Bootstrapped and tested on x86_64-unknown-linux-gnu, I'll apply it
to the trunk in a moment where this issue is latent.

Richard.

2008-08-21  Richard Guenther  <rguenther@suse.de>

        PR middle-end/36817
        * tree-chrec.c (chrec_apply): Always call chrec_fold_plus which
        makes sure to produce a result of the correct type.

        * gcc.c-torture/compile/pr36817.c: New testcase.

Index: gcc/tree-chrec.c
===================================================================
*** gcc/tree-chrec.c    (revision 139376)
--- gcc/tree-chrec.c    (working copy)
*************** chrec_apply (unsigned var,
*** 579,586 ****
        /* "{a, +, b} (x)"  ->  "a + b*x".  */
        x = chrec_convert_rhs (type, x, NULL_TREE);
        res = chrec_fold_multiply (TREE_TYPE (x), CHREC_RIGHT (chrec), x);
!       if (!integer_zerop (CHREC_LEFT (chrec)))
!       res = chrec_fold_plus (type, CHREC_LEFT (chrec), res);
      }

    else if (TREE_CODE (chrec) != POLYNOMIAL_CHREC)
--- 579,585 ----
        /* "{a, +, b} (x)"  ->  "a + b*x".  */
        x = chrec_convert_rhs (type, x, NULL_TREE);
        res = chrec_fold_multiply (TREE_TYPE (x), CHREC_RIGHT (chrec), x);
!       res = chrec_fold_plus (type, CHREC_LEFT (chrec), res);
      }

    else if (TREE_CODE (chrec) != POLYNOMIAL_CHREC)
Index: gcc/testsuite/gcc.c-torture/compile/pr36817.c
===================================================================
*** gcc/testsuite/gcc.c-torture/compile/pr36817.c       (revision 0)
--- gcc/testsuite/gcc.c-torture/compile/pr36817.c       (revision 0)
***************
*** 0 ****
--- 1,10 ----
+ void xxx()
+ {
+   unsigned i;
+   unsigned *p=0;
+   for(i=0; i<4; ++i)
+     *p++=0;
+   for(i=0; i<4; ++i)
+     *p++=0;
+ }
+ 


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=36817

[Bug middle-end/36817] [4.3 Regression] internal compiler error: in compare_values_warnv

[rguenth at gcc dot gnu dot org]

------- Comment #12 from rguenth at gcc dot gnu dot org  2008-08-21 13:51 -------
Subject: Bug 36817

Author: rguenth
Date: Thu Aug 21 13:50:30 2008
New Revision: 139385

URL: http://gcc.gnu.org/viewcvs?root=gcc&view=rev&rev=139385
Log:
2008-08-21  Richard Guenther  <rguenther@suse.de>

        PR middle-end/36817
        * tree-chrec.c (chrec_apply): Always call chrec_fold_plus which
        makes sure to produce a result of the correct type.

        * gcc.c-torture/compile/pr36817.c: New testcase.

Added:
    trunk/gcc/testsuite/gcc.c-torture/compile/pr36817.c
Modified:
    trunk/gcc/ChangeLog
    trunk/gcc/testsuite/ChangeLog
    trunk/gcc/tree-chrec.c


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=36817

[Bug middle-end/36817] [4.3 Regression] internal compiler error: in compare_values_warnv

[jsm28 at gcc dot gnu dot org]

------- Comment #13 from jsm28 at gcc dot gnu dot org  2008-08-27 22:05 -------
4.3.2 is released, changing milestones to 4.3.3.


-- 

jsm28 at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
   Target Milestone|4.3.2                       |4.3.3


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=36817

[Bug middle-end/36817] [4.3 Regression] internal compiler error: in compare_values_warnv

[rguenth at gcc dot gnu dot org]

------- Comment #14 from rguenth at gcc dot gnu dot org  2008-08-28 14:16 -------
Fixed.


-- 

rguenth at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|ASSIGNED                    |RESOLVED
      Known to fail|4.3.0 4.3.1                 |4.3.0 4.3.1 4.3.2
      Known to work|4.2.4 4.4.0                 |4.2.4 4.3.3 4.4.0
         Resolution|                            |FIXED


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=36817

[Bug middle-end/36817] [4.3 Regression] internal compiler error: in compare_values_warnv

[rguenth at gcc dot gnu dot org]

------- Comment #15 from rguenth at gcc dot gnu dot org  2008-08-28 14:17 -------
Subject: Bug 36817

Author: rguenth
Date: Thu Aug 28 14:15:49 2008
New Revision: 139708

URL: http://gcc.gnu.org/viewcvs?root=gcc&view=rev&rev=139708
Log:
2008-08-28  Richard Guenther  <rguenther@suse.de>

        PR middle-end/36817
        * tree-chrec.c (chrec_apply): Always call chrec_fold_plus which
        makes sure to produce a result of the correct type.

        * gcc.c-torture/compile/pr36817.c: New testcase.

Added:
    branches/gcc-4_3-branch/gcc/testsuite/gcc.c-torture/compile/pr36817.c
Modified:
    branches/gcc-4_3-branch/gcc/ChangeLog
    branches/gcc-4_3-branch/gcc/testsuite/ChangeLog
    branches/gcc-4_3-branch/gcc/tree-chrec.c


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=36817