[Bug optimization/13067] New: ICE involving operator++

[Bug optimization/13067] New: ICE involving operator++

[bryner at brianryner dot com]

I see this ICE with a tree-ssa branch tree pulled today.  Reduced testcase
coming up.

-- 
           Summary: ICE involving operator++
           Product: gcc
           Version: tree-ssa
            Status: UNCONFIRMED
          Severity: critical
          Priority: P2
         Component: optimization
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: bryner at brianryner dot com
                CC: gcc-bugs at gcc dot gnu dot org
  GCC host triplet: i686-pc-linux-gnu


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=13067

[Bug optimization/13067] ICE involving operator++

[bryner at brianryner dot com]

------- Additional Comments From bryner at brianryner dot com  2003-11-16 06:15 -------
Created an attachment (id=5147)
 --> (http://gcc.gnu.org/bugzilla/attachment.cgi?id=5147&action=view)
reduced testcase

This is as small as I was able to get the testcase, but I still don't
understand exactly what the trigger is.  It is definitely necessary to invoke
operator++ on Iterator inside the loop.

Compiled with:
$ c++ -c -Os -o foo.o test_ice_2.cpp

Output:
test_ice_2.cpp: In function `void foo(char)':
test_ice_2.cpp:9: internal compiler error: Segmentation fault
Please submit a full bug report,
with preprocessed source if appropriate.


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=13067

[Bug optimization/13067] [tree-ssa] ICE involving operator++

[bryner at brianryner dot com]

-- 
           What    |Removed                     |Added
----------------------------------------------------------------------------
           Keywords|                            |ice-on-valid-code
            Summary|ICE involving operator++    |[tree-ssa] ICE involving
                   |                            |operator++


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=13067

[Bug optimization/13067] [tree-ssa] ICE involving operator++

[pinskia at gcc dot gnu dot org]

------- Additional Comments From pinskia at gcc dot gnu dot org  2003-11-16 08:50 -------
I can confirm this on the tree-ssa (20031115).
Here is the backtrace:
#0  operand_equal_p (arg0=0x0, arg1=0x4186b6f0, only_const=0) at /Volumes/UFS_Partition/
pinskia/src/gccssa/src/gcc/fold-const.c:1974
#1  0x003f5af8 in cfg_remove_useless_stmts () at /Volumes/UFS_Partition/pinskia/src/gccssa/src/
gcc/tree-cfg.c:1357
#2  0x003f5af8 in cfg_remove_useless_stmts () at /Volumes/UFS_Partition/pinskia/src/gccssa/src/
gcc/tree-cfg.c:1357
#3  0x0027b128 in rewrite_out_of_ssa (fndecl=0x63d078, phase=TDI_optimized) at /Volumes/
UFS_Partition/pinskia/src/gccssa/src/gcc/tree-ssa.c:2484
#4  0x002d0e2c in tree_rest_of_compilation (fndecl=0x0, nested_p=6541432) at /Volumes/
UFS_Partition/pinskia/src/gccssa/src/gcc/tree-optimize.c:173
#5  0x000e372c in expand_body (fn=0x41902d90) at /Volumes/UFS_Partition/pinskia/src/gccssa/
src/gcc/cp/semantics.c:2874
#6  0x002c2620 in cgraph_expand_function (node=0x63df00) at /Volumes/UFS_Partition/pinskia/
src/gccssa/src/gcc/cgraphunit.c:496
#7  0x002c4980 in cgraph_optimize () at /Volumes/UFS_Partition/pinskia/src/gccssa/src/gcc/
cgraphunit.c:1316
#8  0x0008beb0 in finish_file () at /Volumes/UFS_Partition/pinskia/src/gccssa/src/gcc/cp/decl2.c:
2871
#9  0x00140ea8 in c_common_parse_file (set_yydebug=0) at /Volumes/UFS_Partition/pinskia/src/
gccssa/src/gcc/c-opts.c:1228
#10 0x001749a4 in toplev_main (argc=4294967295, argv=0x0) at /Volumes/UFS_Partition/
pinskia/src/gccssa/src/gcc/toplev.c:1880
#11 0x0014cef8 in main (argc=0, argv=0x4186b6f0) at /Volumes/UFS_Partition/pinskia/src/
gccssa/src/gcc/main.c:35

-- 
           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |NEW
     Ever Confirmed|                            |1
   Last reconfirmed|0000-00-00 00:00:00         |2003-11-16 08:50:16
               date|                            |


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=13067

[Bug optimization/13067] [tree-ssa] ICE involving operator++

[pinskia at gcc dot gnu dot org]

------- Additional Comments From pinskia at gcc dot gnu dot org  2003-11-16 18:58 -------
For this one, I am wondering if there are just typos in the function cfg_remove_useless_stmts_bb.
val and var are very closely named.

-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=13067

[Bug optimization/13067] [tree-ssa] ICE involving operator++

[pinskia at gcc dot gnu dot org]

-- 
           What    |Removed                     |Added
----------------------------------------------------------------------------
   Target Milestone|---                         |tree-ssa


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=13067

[Bug optimization/13067] [tree-ssa] ICE involving operator++

[steven at gcc dot gnu dot org]

------- Additional Comments From steven at gcc dot gnu dot org  2003-11-26 00:29 -------
I cannot reproduce this with: 
 
GNU C++ version 3.5-tree-ssa 20031125 (merged 20031123) (i686-pc-linux-gnu) 
        compiled by GNU C version 3.5-tree-ssa 20031125 (merged 20031123) 
 
However, this code in cfg_remove_useless_stmts_bb seems pretty silly to me: 
 
  for (bsi = bsi_start (bb); !bsi_end_p (bsi);)  
    {  
      stmt = bsi_stmt (bsi);  
  
      if (!var)  
        {  
          bsi_next (&bsi);  
          continue;  
        }  
 
which I interpret as 
 
"if (var == NULL) { walk all statements in this basic block, but do nothing }" 
 
That's probably not related to this bug if it still exists, though ;-) 
 

-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=13067

[Bug optimization/13067] [tree-ssa] ICE involving operator++

[pinskia at gcc dot gnu dot org]

------- Additional Comments From pinskia at gcc dot gnu dot org  2003-11-26 00:40 -------
This was fixed (I had forgot to close this as I had said I was going to commiting a testcase) with: 
<http://gcc.gnu.org/ml/gcc-patches/2003-11/msg01727.html>.
Mine for now to remind me to commit a testcase.

-- 
           What    |Removed                     |Added
----------------------------------------------------------------------------
         AssignedTo|unassigned at gcc dot gnu   |pinskia at gcc dot gnu dot
                   |dot org                     |org
             Status|NEW                         |ASSIGNED


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=13067

[Bug optimization/13067] [tree-ssa] ICE involving operator++

[cvs-commit at gcc dot gnu dot org]

------- Additional Comments From cvs-commit at gcc dot gnu dot org  2003-12-01 04:54 -------
Subject: Bug 13067

CVSROOT:	/cvs/gcc
Module name:	gcc
Branch: 	tree-ssa-20020619-branch
Changes by:	pinskia@gcc.gnu.org	2003-12-01 04:54:14

Modified files:
	gcc/testsuite  : ChangeLog.tree-ssa 
Added files:
	gcc/testsuite/g++.dg/opt: cfg4.C 

Log message:
	2003-11-30  Andrew Pinski <pinskia@physics.uc.edu>
	
	PR optimization/13067
	* g++.dg/opt/cfg4.C: New test.

Patches:
http://gcc.gnu.org/cgi-bin/cvsweb.cgi/gcc/gcc/testsuite/g++.dg/opt/cfg4.C.diff?cvsroot=gcc&only_with_tag=tree-ssa-20020619-branch&r1=NONE&r2=1.1.2.1
http://gcc.gnu.org/cgi-bin/cvsweb.cgi/gcc/gcc/testsuite/ChangeLog.tree-ssa.diff?cvsroot=gcc&only_with_tag=tree-ssa-20020619-branch&r1=1.1.2.125&r2=1.1.2.126



-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=13067

[Bug optimization/13067] [tree-ssa] ICE involving operator++

[pinskia at gcc dot gnu dot org]

------- Additional Comments From pinskia at gcc dot gnu dot org  2003-12-01 04:55 -------
Fixed alread, just finally commited the testcase :). 

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


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=13067