[Bug c/23929] New: segfault in expand_simple_operations, tree-ssa-loop-niter.c:637

[Bug c/23929] New: segfault in expand_simple_operations, tree-ssa-loop-niter.c:637

[marcus at jet dot franken dot de]

following testcase (extracted from libgphoto2) segfaults 
the compiler on amd64. 
 
/home/marcus/projects/gcc/BIN/bin/gcc     -O2   -c library.i   
library.i: In function 'f': 
library.i:1: internal compiler error: Segmentation fault 
Please submit a full bug report, 
with preprocessed source if appropriate. 
See <URL:http://gcc.gnu.org/bugs.html> for instructions.

-- 
           Summary: segfault in expand_simple_operations, tree-ssa-loop-
                    niter.c:637
           Product: gcc
           Version: 4.1.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P2
         Component: c
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: marcus at jet dot franken dot de
                CC: gcc-bugs at gcc dot gnu dot org
 GCC build triplet: x86_64-unknown-linux-gnu
  GCC host triplet: x86_64-unknown-linux-gnu
GCC target triplet: x86_64-unknown-linux-gnu


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=23929

[Bug c/23929] segfault in expand_simple_operations, tree-ssa-loop-niter.c:637

[marcus at jet dot franken dot de]

------- Additional Comments From marcus at jet dot franken dot de  2005-09-17 19:43 -------
Created an attachment (id=9749)
 --> (http://gcc.gnu.org/bugzilla/attachment.cgi?id=9749&action=view)
library.i

gcc -O2 -c library.i

-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=23929

[Bug tree-optimization/23929] segfault in expand_simple_operations, tree-ssa-loop-niter.c:637

[pinskia at gcc dot gnu dot org]

-- 
           What    |Removed                     |Added
----------------------------------------------------------------------------
          Component|c                           |tree-optimization
           Keywords|                            |ice-on-valid-code


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=23929

[Bug tree-optimization/23929] [4.1 Regression] segfault in expand_simple_operations, tree-ssa-loop-niter.c:637

[pinskia at gcc dot gnu dot org]

------- Additional Comments From pinskia at gcc dot gnu dot org  2005-09-17 19:53 -------
Confirmed, a regression from 4.0.0.
backtrace:
#0  expand_simple_operations (expr=0x0) at /home/pinskia/src/onetest/gcc/gcc/tree-ssa-loop-
niter.c:637
#1  0x00000000004cee15 in expand_simple_operations (expr=0x2a95c2ee70) at /home/pinskia/src/
onetest/gcc/gcc/tree-ssa-loop-niter.c:648
#2  0x00000000004cee15 in expand_simple_operations (expr=0x2a95c37080) at /home/pinskia/src/
onetest/gcc/gcc/tree-ssa-loop-niter.c:648
#3  0x00000000004cee15 in expand_simple_operations (expr=0x2a95c37280) at /home/pinskia/src/
onetest/gcc/gcc/tree-ssa-loop-niter.c:648
#4  0x00000000004cee15 in expand_simple_operations (expr=0x2a95c2f870) at /home/pinskia/src/
onetest/gcc/gcc/tree-ssa-loop-niter.c:648
#5  0x00000000004cee15 in expand_simple_operations (expr=0x2a95c2f8c0) at /home/pinskia/src/
onetest/gcc/gcc/tree-ssa-loop-niter.c:648
#6  0x00000000004cf52c in tree_simplify_using_condition_1 (cond=0x2a95a664b0, 
expr=0x2a95c2f8c0) at /home/pinskia/src/onetest/gcc/gcc/tree-ssa-loop-niter.c:777
#7  0x00000000004cfa8e in simplify_using_initial_conditions (loop=Variable "loop" is not available.
) at /home/pinskia/src/onetest/gcc/gcc/tree-ssa-loop-niter.c:805
#8  0x00000000004cff1f in number_of_iterations_exit (loop=0xbcd540, exit=Variable "exit" is not 
available.
) at /home/pinskia/src/onetest/gcc/gcc/tree-ssa-loop-niter.c:990
#9  0x00000000007e6a2a in number_of_iterations_in_loop (loop=0xbcd540) at /home/pinskia/src/
onetest/gcc/gcc/tree-scalar-evolution.c:2284
#10 0x00000000007e7f76 in compute_overall_effect_of_inner_loop (loop=0xbcd540, 
evolution_fn=0x2a95c2f6e0) at /home/pinskia/src/onetest/gcc/gcc/tree-scalar-evolution.c:471
#11 0x00000000007eb704 in follow_ssa_edge (loop=0xbcd450, def=0x2a95c28000, 
halting_phi=0x2a95c28100, evolution_of_loop=0x7fbffff2c0)
    at /home/pinskia/src/onetest/gcc/gcc/tree-scalar-evolution.c:1389
#12 0x00000000007ebf87 in follow_ssa_edge_in_rhs (loop=0xbcd450, at_stmt=0x2a95a66af0, 
rhs=0x2a95c27370, halting_phi=Variable "halting_phi" is not available.
) at /home/pinskia/src/onetest/gcc/gcc/tree-scalar-evolution.c:1110
#13 0x00000000007eb504 in follow_ssa_edge (loop=0xbcd450, def=0x2a95a66af0, 
halting_phi=0x2a95c28100, evolution_of_loop=0x7fbffff2c0)
    at /home/pinskia/src/onetest/gcc/gcc/tree-scalar-evolution.c:1442
#14 0x00000000007eb589 in follow_ssa_edge (loop=0xbcd450, def=0x2a95c24b00, 
halting_phi=0x2a95c28100, evolution_of_loop=0x7fbffff330)
    at /home/pinskia/src/onetest/gcc/gcc/tree-scalar-evolution.c:1293
#15 0x00000000007eb607 in follow_ssa_edge (loop=0xbcd450, def=0x2a95c24300, 
halting_phi=0x2a95c28100, evolution_of_loop=0x7fbffff390)
    at /home/pinskia/src/onetest/gcc/gcc/tree-scalar-evolution.c:1293
#16 0x00000000007e8770 in analyze_scalar_evolution_1 (loop=0xbcd450, var=0x2a95c25d20, 
res=0x0) at /home/pinskia/src/onetest/gcc/gcc/tree-scalar-evolution.c:1494
#17 0x00000000007e8ae7 in analyze_scalar_evolution (loop=0xbcd450, var=0x0) at /home/pinskia/
src/onetest/gcc/gcc/tree-scalar-evolution.c:1856
#18 0x00000000007ea405 in analyze_scalar_evolution_in_loop (wrto_loop=0xbcd450, 
use_loop=0xbcd450, version=Variable "version" is not available.
) at /home/pinskia/src/onetest/gcc/gcc/tree-scalar-evolution.c:1880
#19 0x00000000007eace7 in simple_iv (loop=0xbcd450, stmt=0x2a95c28100, op=0x2a95c25d20, 
base=0x7fbffff468, step=0x7fbffff470, allow_nonconstant_step=1 '\001')
    at /home/pinskia/src/onetest/gcc/gcc/tree-scalar-evolution.c:2597
#20 0x00000000004f1b9e in find_induction_variables (data=0x7fbffff500) at /home/pinskia/src/
onetest/gcc/gcc/tree-ssa-loop-ivopts.c:889
#21 0x00000000004f5755 in tree_ssa_iv_optimize (loops=0xbda050) at /home/pinskia/src/onetest/
gcc/gcc/tree-ssa-loop-ivopts.c:5933


-- 
           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |NEW
     Ever Confirmed|                            |1
      Known to fail|                            |4.1.0
      Known to work|                            |4.0.0
   Last reconfirmed|0000-00-00 00:00:00         |2005-09-17 19:53:05
               date|                            |
            Summary|segfault in                 |[4.1 Regression] segfault in
                   |expand_simple_operations,   |expand_simple_operations,
                   |tree-ssa-loop-niter.c:637   |tree-ssa-loop-niter.c:637
   Target Milestone|---                         |4.1.0


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=23929

[Bug tree-optimization/23929] [4.1 Regression] segfault in expand_simple_operations, tree-ssa-loop-niter.c:637

[pinskia at gcc dot gnu dot org]

------- Additional Comments From pinskia at gcc dot gnu dot org  2005-09-17 22:47 -------
This has been failing since at least "4.1.0 20050705".

-- 
           What    |Removed                     |Added
----------------------------------------------------------------------------
  GCC build triplet|x86_64-unknown-linux-gnu    |
   GCC host triplet|x86_64-unknown-linux-gnu    |
 GCC target triplet|x86_64-unknown-linux-gnu    |


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=23929

[Bug tree-optimization/23929] [4.1 Regression] segfault in expand_simple_operations, tree-ssa-loop-niter.c:637

[pinskia at gcc dot gnu dot org]

------- Additional Comments From pinskia at gcc dot gnu dot org  2005-09-17 22:48 -------
It worked with "4.1.0 20050321".

-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=23929

[Bug tree-optimization/23929] [4.1 Regression] segfault in expand_simple_operations, tree-ssa-loop-niter.c:637

[pinskia at gcc dot gnu dot org]

------- Additional Comments From pinskia at gcc dot gnu dot org  2005-09-17 22:50 -------
It also fails with "4.1.0 20050530".

-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=23929

[Bug tree-optimization/23929] [4.1 Regression] segfault in expand_simple_operations, tree-ssa-loop-niter.c:637

[steven at gcc dot gnu dot org]

------- Additional Comments From steven at gcc dot gnu dot org  2005-09-18 11:23 -------
Janis, could you please unleash your binary search scripts on this one? 

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


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=23929

[Bug tree-optimization/23929] [4.1 Regression] segfault in expand_simple_operations, tree-ssa-loop-niter.c:637

[janis at gcc dot gnu dot org]

------- Additional Comments From janis at gcc dot gnu dot org  2005-09-19 18:22 -------
A reghunt on powerpc-linux shows the segfault starts with this patch from
rguenth@gcc.gnu.org:

  http://gcc.gnu.org/ml/gcc-cvs/2005-05/msg00537.html

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


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=23929

Re: [Bug tree-optimization/23929] [4.1 Regression] segfault in expand_simple_operations, tree-ssa-loop-niter.c:637

[Andrew Pinski]

On Sep 19, 2005, at 2:22 PM, janis at gcc dot gnu dot org wrote:

>
> ------- Additional Comments From janis at gcc dot gnu dot org  
> 2005-09-19 18:22 -------
> A reghunt on powerpc-linux shows the segfault starts with this patch 
> from
> rguenth@gcc.gnu.org:

Then this is a latent bug as it does not touch any of the backtrace.

Thanks,
Andrew Pinski

[Bug tree-optimization/23929] [4.1 Regression] segfault in expand_simple_operations, tree-ssa-loop-niter.c:637

[pinskia at physics dot uc dot edu]

------- Additional Comments From pinskia at physics dot uc dot edu  2005-09-19 18:53 -------
Subject: Re:  [4.1 Regression] segfault in expand_simple_operations, tree-ssa-loop-niter.c:637


On Sep 19, 2005, at 2:22 PM, janis at gcc dot gnu dot org wrote:

>
> ------- Additional Comments From janis at gcc dot gnu dot org  
> 2005-09-19 18:22 -------
> A reghunt on powerpc-linux shows the segfault starts with this patch 
> from
> rguenth@gcc.gnu.org:

Then this is a latent bug as it does not touch any of the backtrace.

Thanks,
Andrew Pinski



-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=23929

[Bug tree-optimization/23929] [4.1 Regression] segfault in expand_simple_operations, tree-ssa-loop-niter.c:637

[janis187 at us dot ibm dot com]

------- Additional Comments From janis187 at us dot ibm dot com  2005-09-19 21:08 -------
It is not true that the function that contains a bug that causes a segfault is
always in the backtrace for the failure; this isn't enough information to claim
this is a latent bug.

-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=23929

[Bug tree-optimization/23929] [4.1 Regression] segfault in expand_simple_operations, tree-ssa-loop-niter.c:637

[pinskia at gcc dot gnu dot org]

------- Additional Comments From pinskia at gcc dot gnu dot org  2005-09-19 21:12 -------
it is even more obvious it was a latent bug from looking at what we looking at when we are scanning 
over the operands:
lineD.1272[318 - (<unnamed type>) ivtmp.37D.1332_3]

Where this is an ARRAY_REF and a couple of the ARRAY_REFs can be NULL.

-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=23929

[Bug tree-optimization/23929] [4.1 Regression] segfault in expand_simple_operations, tree-ssa-loop-niter.c:637

[pinskia at gcc dot gnu dot org]

------- Additional Comments From pinskia at gcc dot gnu dot org  2005-09-19 21:14 -------
(In reply to comment #10)
> it is even more obvious it was a latent bug from looking at what we looking at when we are scanning 
> over the operands:
> lineD.1272[318 - (<unnamed type>) ivtmp.37D.1332_3]
> 
> Where this is an ARRAY_REF and a couple of the ARRAY_REFs can be NULL.

s/couple/couple of the operands/

-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=23929

[Bug tree-optimization/23929] [4.1 Regression] segfault in expand_simple_operations, tree-ssa-loop-niter.c:637

[jakub at gcc dot gnu dot org]

-- 
           What    |Removed                     |Added
----------------------------------------------------------------------------
         AssignedTo|unassigned at gcc dot gnu   |jakub at gcc dot gnu dot org
                   |dot org                     |
                URL|                            |http://gcc.gnu.org/ml/gcc-
                   |                            |patches/2005-
                   |                            |09/msg01252.html
             Status|NEW                         |ASSIGNED
   Last reconfirmed|2005-09-17 19:53:05         |2005-09-20 12:48:00
               date|                            |


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=23929

[Bug tree-optimization/23929] [4.1 Regression] segfault in expand_simple_operations, tree-ssa-loop-niter.c:637

[cvs-commit at gcc dot gnu dot org]

------- Additional Comments From cvs-commit at gcc dot gnu dot org  2005-09-20 19:10 -------
Subject: Bug 23929

CVSROOT:	/cvs/gcc
Module name:	gcc
Changes by:	jakub@gcc.gnu.org	2005-09-20 19:10:45

Modified files:
	gcc            : ChangeLog tree-ssa-loop-niter.c 
	gcc/testsuite  : ChangeLog 
Added files:
	gcc/testsuite/gcc.c-torture/compile: pr23929.c 

Log message:
	PR tree-optimization/23929
	* tree-ssa-loop-niter.c (expand_simple_operations): Return immediately
	if expr is NULL.
	
	* gcc.c-torture/compile/pr23929.c: New test.

Patches:
http://gcc.gnu.org/cgi-bin/cvsweb.cgi/gcc/gcc/ChangeLog.diff?cvsroot=gcc&r1=2.9989&r2=2.9990
http://gcc.gnu.org/cgi-bin/cvsweb.cgi/gcc/gcc/tree-ssa-loop-niter.c.diff?cvsroot=gcc&r1=2.43&r2=2.44
http://gcc.gnu.org/cgi-bin/cvsweb.cgi/gcc/gcc/testsuite/ChangeLog.diff?cvsroot=gcc&r1=1.6086&r2=1.6087
http://gcc.gnu.org/cgi-bin/cvsweb.cgi/gcc/gcc/testsuite/gcc.c-torture/compile/pr23929.c.diff?cvsroot=gcc&r1=NONE&r2=1.1



-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=23929

[Bug tree-optimization/23929] [4.1 Regression] segfault in expand_simple_operations, tree-ssa-loop-niter.c:637

[pinskia at gcc dot gnu dot org]

------- Additional Comments From pinskia at gcc dot gnu dot org  2005-09-20 19:18 -------
Fixed.

-- 
           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|ASSIGNED                    |RESOLVED
         Resolution|                            |FIXED


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=23929